JP7479689B2 - Pretreatment device for microorganism testing, pretreatment mechanism for microorganism testing, and pretreatment method for microorganism testing - Google Patents

Description

The present invention relates to a pretreatment device for microbiological testing, a pretreatment mechanism for microbiological testing, and a pretreatment method for microbiological testing. More specifically, the present invention relates to a pretreatment device for microbiological testing, a pretreatment mechanism for microbiological testing, and a pretreatment method for microbiological testing that can automate the pretreatment of samples in microbiological testing and perform accurate and highly reproducible processing.

In microbial testing of food, pharmaceuticals, and cosmetics, bacteriological analysis or microbial testing is performed on various samples. The procedures for this microbial testing are stipulated in guidelines such as the Food Sanitation Inspection Guideline supervised by the Ministry of Health, Labor, and Welfare, as well as in the Japanese Food Safety Agency Act and JIS, and involve a series of procedures that involve extracting bacteria from the sample and culturing the extract in a medium.

The flow of microbiological testing is generally as follows:

First, the target sample is broken down into small pieces within a certain range of mass, the mass of the sample is weighed, and the sample is placed in a sterilized storage bag called a stomacher bag.

Additionally, a dilution solution such as sterile phosphate buffer solution is placed in the storage bag so that the sample mass is diluted 10-fold.

Then, a homogenizer is used to crush the sample in the diluted solution using the pressing force of a reciprocating paddle or similar device, and the sample in the storage bag is crushed, dispersed, and suspended, and bacteria are extracted from the sample (stomacher processing).

The solution in the storage bag that has been subjected to extraction processing using a homogenizer is collected and serially diluted with a dilution solution. The diluted solutions of each dilution concentration are then inoculated into a medium capable of cultivating microorganisms, and the medium is cultured in an incubator or the like for a certain period of time, after which microbial testing, such as measuring the viable cell count, is performed.

During cultivation, depending on the number of bacteria contained in the original sample, it can be difficult to measure the number of bacteria, so a commonly used method is to adjust the measurement range by gradually diluting the sample as appropriate, and then count the number of bacteria contained in the sample by back-calculating the dilution rate.

As described above, microbiological testing requires a series of multiple steps: weighing the sample, adding a dilution solution, extracting bacteria from the sample, diluting the extraction solution, and inoculating the culture medium.

In addition, homogenizers used in bacterial extraction processing have been improved to improve operability and processing efficiency; for example, devices have been proposed that control the paddle stopping position and speed to speed up processing. (See Patent Document 1.)

JP 2007-44600 A

However, currently, there is no technology that uses equipment to automate multiple steps in microbiological testing, from weighing the sample in a storage bag, pouring a dilution solution into the storage bag, extracting bacteria using a stomacher, and collecting the solution after crushing.

In addition, in a single microbiological test, the number of samples required can be several dozen or more, and it takes a lot of time and effort to carry out the various tasks of weighing, injecting diluted solutions, extracting bacteria, and collecting solutions for each sample.

In addition, the weighing and dilution solution injection processes are often done manually, which can lead to errors due to human factors such as dispensing errors when operating the dispenser (pipette) and weighing errors, resulting in a lack of accuracy in processing. Furthermore, errors can lead to problems such as low reproducibility of test results.

The present invention was devised in light of the above points, and aims to provide a pretreatment device for microbiological testing, a pretreatment mechanism for microbiological testing, and a pretreatment method for microbiological testing that can automate the pretreatment of samples in microbiological testing and perform accurate and highly reproducible processing.

In order to achieve the above object, the pretreatment device for microorganism testing of the present invention is a pretreatment device for microorganism testing that automatically performs a series of operations, including injecting a dilution solution into a storage bag containing a specified sample, pressing the storage bag to crush and disperse the specified sample into a suspension, and collecting the suspended sample. The device is equipped with a transport mechanism for transporting the storage bag, a weighing unit for weighing the mass of the specified sample and the storage bag, a sample preparation unit for injecting the dilution solution into the storage bag to prepare the specified sample at a specified dilution ratio according to the value weighed by the weighing unit, a bag arrangement unit in which the storage bag containing the sample prepared by the sample preparation unit is fixedly arranged, and a crushing unit for pressing the storage bag arranged in the bag arrangement unit to crush and disperse the prepared sample into a suspension, and a sample collection unit for collecting the sample suspended by the crushing unit.

The transport mechanism for transporting the storage bag can automatically transport the storage bag containing the sample to the desired position. In other words, the storage bag can be moved between the components that perform various processes on the storage bag. Note that the storage bag referred to here is a bag that is sterilized before use and is capable of storing a certain amount of sample, solution, etc. inside it.

The weighing unit can also measure the mass of a given sample and a storage bag, allowing the accurate mass of the sample to be used in a microorganism test to be measured. The measurement operation can also be performed automatically.

The sample preparation unit injects a diluted solution into the storage bag to obtain a predetermined dilution ratio according to the value weighed by the weighing unit, and prepares a predetermined sample. This allows the target sample to be diluted to a predetermined dilution ratio in the storage bag, and allows automatic pretreatment of the sample to be fed to the homogenizer. An accurate amount of diluted solution can be injected to obtain a predetermined dilution ratio relative to the sample mass. Note that the predetermined dilution ratio includes, for example, dilution in which the total mass of the sample and diluted solution is 10 times the mass of the sample alone. If further stepwise dilution is to be performed in a later process, the injection of the diluted solution into the storage bag will be the first step of dilution.

In addition, the weighing unit weighs the mass of a specified sample and storage bag, and the sample preparation unit prepares a specified sample by injecting a diluted solution into the storage bag to obtain a specified dilution ratio according to the value weighed by the weighing unit. This automatically performs the tasks of weighing the sample and injecting a diluted solution according to the sample's mass, eliminating the effort required for sample pretreatment. In other words, for example, accurate sample weighing to obtain a predetermined dilution ratio is no longer necessary, and the operator only needs to prepare the sample within an error range of, for example, 10 to 15 g, and sample pretreatment for feeding to the homogenizer can be performed quickly and accurately without bothering the operator.

In addition, by fixing and placing the storage bag containing the sample prepared in the sample preparation section in the bag placement section of the homogenizer, the storage bag containing the sample diluted with the dilution solution can be fixed and pressed. In other words, it is possible to apply the pressing force of the crushing section to the sample. In addition, it is possible to promote the crushing of the sample, improving the accuracy of the microorganism test.

The homogenizer's crushing section presses against the storage bag placed in the bag placement section to crush, disperse, and suspend the prepared sample, thereby crushing the sample and extracting the bacteria in the sample into a dilute solution.

In addition, the sample collection unit collects the sample suspended in the crushing unit, allowing the automatic collection of a diluted solution in which the bacteria in the sample have been extracted. In addition, because the sample collection is performed automatically, an accurate amount of solution can be collected.

In addition, if the sample collection unit is equipped with a control mechanism that adjusts the liquid level of the suspended sample in the storage bag to a certain range of heights depending on the amount of diluted solution injected into the storage bag when collecting the suspended sample, it becomes possible to automatically collect the diluted solution from which the bacteria in the sample have been extracted with even greater accuracy and reliability.

In addition, when the crushing section has a pressing surface formed in a direction approximately parallel to the side of the storage bag placed in the bag placement section and is configured to be capable of reciprocating motion along a direction connecting the pressing surface and the side of the storage bag, the reciprocating pressing surface of the crushing section can repeatedly press the side of the storage bag, thereby crushing the sample in the diluted solution and extracting the bacteria in the sample.

In addition, if the crushing section has a pressing surface formed in a direction approximately parallel to the side of the storage bag placed in the bag placement section and is configured to be capable of reciprocating motion along a direction connecting the pressing surface and the side of the storage bag, and the control mechanism controls the position of the pressing surface in the direction in which the pressing surface faces the side of the storage bag to adjust the liquid level, it is possible to adjust the liquid level of the suspended sample in the storage bag to a constant height by controlling the movement of the crushing section and the distance of its movement when collecting the diluted solution from the storage bag.

When the storage bag is placed in the bag placement section, the control mechanism controls the position of the pressing surface in the direction in which it faces the side of the storage bag to adjust the liquid level, and when the pressing surface presses the storage bag and removes air from the internal space from the top of the storage bag, the storage bag is pressed by the crushing section to remove excess air from inside the storage bag before crushing the sample, making it possible to apply sufficient pressing force to the sample in the diluted solution inside the storage bag.

When the storage bag is placed in the bag placement section, the control mechanism controls the position of the pressing surface in the direction in which the pressing surface faces the side of the storage bag, adjusting the liquid level height while the pressing surface presses the storage bag, removing air from the internal space from the top of the storage bag, and when the bag placement section reaches a predetermined position while the pressing surface presses the storage bag, it clamps the top of the storage bag from both sides, and if it has a closing mechanism that closes the top of the storage bag, it can press the storage bag with the pressing surface of the crushing section to remove excess air from inside the storage bag, and then clamp and close the top of the storage bag. This makes it possible to prevent the diluted solution from scattering from the top of the storage bag to the outside when the sample is crushed with the homogenizer, and also to prevent contamination of the surrounding environment, mixing between samples, and contamination due to scattering.

In addition, if multiple crushing sections are provided and are arranged in a line along a direction that is approximately perpendicular to the direction toward the side of the storage bag, and the pressing surfaces of each are arranged at approximately the same height in the vertical direction, it becomes possible for multiple crushing sections to press against one storage bag placed in the bag placement section, thereby improving the efficiency of crushing the sample.

In addition, when multiple crushing units are provided, the pressing surfaces of the multiple crushing units are provided at approximately the same height in the vertical direction, and are arranged side by side along a direction approximately perpendicular to the direction toward the side of the storage bag, and the control mechanism aligns the positions of the multiple pressing surfaces in the direction in which the pressing surfaces face the side of the storage bag, the multiple crushing units can press the side of the storage bag while aligning the positions of the pressing surfaces. This makes it possible to raise the liquid level of the suspended sample in the storage bag uniformly and more reliably with the multiple pressing surfaces.

In addition, if the storage bag has a clip portion attached to its end and formed with a collection port that communicates with the inside of the storage bag, it becomes possible to inject or collect a solution through the collection port.

In addition, when the storage bag has a clip portion attached to its end and has a collection port formed therein that communicates with the inside of the storage bag, and the transport mechanism transports the storage bag by gripping the clip portion, the transport mechanism can grip the clip portion without gripping the storage bag, which is soft and easily deformed, so that the storage bag containing the sample or solution inside can be transported stably.

In addition, the clip part has a collection port formed on its end side, and if the storage bag and clip part are positioned so that the collection port is located at a predetermined position in the sample preparation part and sample collection part, when automatically controlling the dispenser etc., it is possible to inject or collect a solution simply by moving the dispenser etc. to a predetermined position as a target. In other words, since the location of the collection port does not change, it is possible to simplify the control of the movement of the dispenser etc.

In addition, when the sample collection unit is equipped with a stepwise dilution unit that stepwise dilutes the collected suspended sample with a dilution solution, it is possible to automatically stepwise dilute a certain amount of solution collected from the dilution solution in which the bacteria in the sample have been extracted. Furthermore, since the stepwise dilution is performed automatically, the collected solution can be accurately suspended in the dilution solution, stirred, and further collected. As a result, errors in the stepwise dilution process are reduced, and the reproducibility of the test results cultured in the medium can be improved. In addition, for example, even when there are a large number of samples, it is possible to quickly and accurately prepare stepwise dilutions of multiple concentrations from a single sample without bothering the operator.

In addition, if a sample inoculation section is provided that inoculates a specified medium with the sample solution diluted in the stepwise dilution section, the stepwise dilution of the bacterial cells extracted from the sample can be automatically inoculated into the medium. That is, even if the number of samples is many, for example, more than tens of samples, the task of inoculating the medium with the stepwise dilutions of multiple concentrations derived from the samples can be performed quickly and accurately without bothering the operator. Note that the specified medium referred to here includes, for example, plate-shaped medium, film-shaped medium, medium for pour culture, medium for puncture, medium for surface application, etc., which can be used to culture microorganisms.

In addition, when the specified medium is a film medium having a sheet-shaped film medium body with a medium capable of culturing microorganisms and a protective film covering the film medium body, the effort required for preparing the medium is eliminated and sample inoculation is easier than with plate-shaped medium. In addition, since the size is smaller than that of plate-shaped medium, it is possible to supply a larger number of mediums to the device. Furthermore, it is possible to suppress variation in culture results due to the shape of the medium, etc.

In addition, if the specified medium is a film medium having a sheet-like film medium body with a medium capable of culturing microorganisms and a protective film covering the film medium body, and the sample inoculation unit has a film lifting mechanism for lifting the protective film from the film medium body, the protective film can be automatically lifted and inoculated into the film medium body when inoculating the diluted solution of each concentration. After inoculating the film medium body with the diluted solution, the lifted protective film can be released and the film medium can be covered with the protective film again. For example, even when there are a large number of samples, the protective film can be lifted, the sample can be inoculated into the film medium, and the film medium can be covered with the protective film again without bothering the operator, and measurement errors due to the introduction of foreign matter by the operator can be reduced (reduction of human contamination).

In addition, if an identification information assigning mechanism that assigns identification information to a specific medium is provided, the film medium can be identified by assigning identification information using the identification information assigning mechanism. In other words, it is no longer necessary for an operator to manually write identification information on a film medium inoculated with a sample, which can improve work efficiency.

In order to achieve the above object, the pretreatment mechanism for microorganism testing of the present invention is a pretreatment mechanism for microorganism testing that automatically performs a series of operations, including injecting a dilution solution into a storage bag containing a specified sample, pressing the storage bag to crush, disperse, and suspend the specified sample, and collecting the suspended sample. The pretreatment mechanism includes a clip unit that is attached to the end of the storage bag and has a collection port that communicates with the inside of the storage bag, a transport mechanism that transports the storage bag via the clip unit, a weighing unit that weighs the mass of the specified sample and the storage bag, a sample preparation unit that prepares the specified sample by injecting the dilution solution from the collection port into the storage bag so as to achieve a specified dilution ratio according to the value weighed by the weighing unit, a bag arrangement unit in which the storage bag containing the sample prepared by the sample preparation unit is fixedly arranged, and a crushing unit that presses the storage bag arranged in the bag arrangement unit to crush, disperse, and suspend the prepared sample, and a sample collection unit that collects the sample suspended in the crushing unit from the collection port.

Here, the clip portion is attached to the end of the storage bag, and a collection port that communicates with the inside of the storage bag is formed, making it possible to inject or collect a solution through the collection port.

In addition, the sample preparation unit injects a dilution solution from the collection port into the storage bag to obtain a predetermined dilution ratio according to the value weighed by the weighing unit, and prepares a specified sample. This makes it possible to automatically dilute the target sample to a predetermined dilution ratio in the storage bag and pre-treat the sample to be fed to the homogenizer. Also, an accurate amount of dilution solution can be injected to obtain a predetermined dilution ratio relative to the mass of the sample.

In addition, the weighing unit weighs the mass of a given sample and storage bag, and the sample preparation unit prepares a given sample by injecting a diluted solution from a collection port into the storage bag to obtain a given dilution ratio according to the value weighed by the weighing unit. This automatically performs the tasks of weighing the sample and injecting a diluted solution according to the sample's mass, eliminating the effort required for sample pretreatment. In other words, for example, accurate sample weighing to obtain a predetermined dilution ratio is no longer necessary, and the operator only needs to prepare the sample within an error range of, for example, 10 to 15 g, and sample pretreatment for feeding to the homogenizer can be performed quickly and accurately without bothering the operator.

The sample collection unit collects the sample suspended in the crushing unit from the collection port, allowing the automatic collection of a diluted solution in which the bacteria in the sample have been extracted. In addition, because the sample collection is performed automatically, an accurate amount of solution can be collected.

In order to achieve the above object, the pretreatment method for microorganism testing of the present invention is a pretreatment method for microorganism testing that automatically performs a series of operations, including injecting a dilution solution into a storage bag containing a specified sample, pressing the storage bag to crush, disperse, and suspend the specified sample, and collecting the suspended sample, and includes a weighing step for weighing the mass of the specified sample and the storage bag, a sample preparation step for injecting the dilution solution into the storage bag to prepare the specified sample at a specified dilution ratio according to the value weighed by the weighing unit, a stomacher processing step for pressing the storage bag containing the sample prepared in the sample preparation unit to crush, disperse, and suspend the prepared sample, and a sample collection step for collecting the sample suspended in the stomacher processing step.

Here, the weighing process weighs the mass of a given sample and a storage bag, thereby making it possible to measure the exact mass of the sample to be subjected to the microbiological test. In addition, the measurement operation can be performed automatically.

In addition, the sample preparation process injects a dilution solution into the storage bag to prepare a specified sample at a specified dilution ratio according to the value weighed by the weighing unit, making it possible to automatically dilute the target sample in the storage bag to a specified dilution ratio and pre-treat the sample to be fed to the homogenizer. Also, an accurate amount of dilution solution can be injected to obtain a specified dilution ratio relative to the mass of the sample.

The stomacher processing step also presses the storage bag containing the sample prepared in the sample preparation section to crush, disperse, and suspend the prepared sample, thereby crushing the sample and extracting the bacteria in the sample into a dilution solution.

In addition, the sample collection process collects the sample suspended in the stomacher processing process, allowing the automatic collection of a diluted solution in which the bacteria in the sample have been extracted. In addition, because the sample is collected automatically, an accurate amount of solution can be collected.

In addition, if the sample collection process includes a control process for adjusting the liquid level of the suspended sample in the storage bag to a certain range of heights depending on the amount of diluted solution injected into the storage bag, it becomes possible to automatically collect the diluted solution from which the bacteria in the sample have been extracted with even greater accuracy and reliability.

In addition, if the control process adjusts the liquid level by using a crushing unit that reciprocates to press the storage bag in the stomacher processing process and controlling the position of the crushing unit along the direction of pressing the storage bag, it is possible to adjust the liquid level of the suspended sample in the storage bag to a constant height by using the movement of the crushing unit to control the distance of movement when collecting the diluted solution from the storage bag.

In addition, when the medium for culturing microorganisms by inoculating a sample solution obtained by serially diluting the sample collected in the sample collection process is a film medium having a sheet-shaped film medium body having a medium capable of culturing microorganisms and a protective film covering the film medium body, the effort required for preparing the medium is eliminated and inoculation of the sample is easier than with a plate-shaped medium. In addition, since the size is smaller than that of a plate-shaped medium, it is possible to supply a larger number of media to the device. Furthermore, it is possible to suppress variation in the culture results due to the shape of the medium, etc.

In addition, if the medium in which the sample collected in the sample collection step is inoculated with a sample solution that is serially diluted and used to culture microorganisms is a film medium having a sheet-like film medium body with a medium capable of culturing microorganisms and a protective film that covers the film medium body, and if the sample inoculation step includes a film lifting step of lifting the protective film from the film medium body, the protective film can be automatically lifted and inoculated into the film medium body when inoculating the diluted solution of each concentration. In addition, after inoculating the film medium body with the diluted solution, the lifted protective film can be released and the film medium can be covered with the protective film again. For example, even when there are a large number of samples, it is possible to inoculate the medium with the sample quickly and accurately without bothering the operator with the tasks of lifting the protective film, inoculating the film medium with the sample, and covering it with the protective film again.

The pretreatment device for microbial testing, the pretreatment mechanism for microbial testing, and the pretreatment method for microbial testing according to the present invention can automate the pretreatment of samples in microbial testing, enabling accurate and highly reproducible processing.

1 is a schematic plan view showing the overall device configuration of a pretreatment device for a microorganism test according to an embodiment of the present invention; FIG. 2 is a schematic perspective view of the device shown in FIG. 1 . 2 is a schematic perspective view showing a part of the internal structure including the transport rail of the device shown in FIG. 1 . FIG. 2 is a schematic perspective view showing a part of the internal structure of the device shown in FIG. 1 . FIG. 2A is a schematic perspective view showing the internal structure of a stomacher bag with a filter and a clip portion, and FIG. 2B is a schematic front view of the stomacher bag with a filter and the clip portion. 6(a) is a schematic perspective view showing a state in which a stomacher bag is housed in a stand portion, and FIG. 6(b) is a schematic plan view corresponding to FIG. 6(a). 7A is a schematic perspective view showing a state in which a stomacher bag is housed in a stomacher, and FIG. 7B is a schematic perspective view showing the view in FIG. 7A from a different angle. 1A is a schematic side view showing the state before the stomacher bag is pressed with a paddle when collecting a sample solution, and FIG. 1B is a schematic side view showing the state after the stomacher bag is pressed with a paddle when collecting a sample solution. 11 is a schematic perspective view showing a state in which the protective film is lifted by the film lifting mechanism. FIG. 1 is a schematic diagram showing the flow of sample processing in each component of a pretreatment device 1. FIG. 10, a schematic diagram showing the flow of sample processing in each component using the pretreatment device 1 is shown.

Hereinafter, embodiments of the present invention will be described with reference to the drawings for the purpose of understanding the present invention.
[Embodiment]
An embodiment of the present invention will be described as an example of a pretreatment mechanism for microorganism testing and a pretreatment device for microorganism testing to which the present invention is applied. Note that the content described below is merely an example of a structure to which the present invention is applied, and the embodiment of the present invention is not limited to the structure described below.

[Overall configuration of the device]
A pretreatment device 1, which is an example of a pretreatment device for microorganism testing to which the present invention is applied, includes a stand unit 2, a balance 3, a stomacher dispenser 4, a stomacher 5, a test tube mixer 6, a film opener 7, and a medium stocker 10 (see FIG. 1). The pretreatment device 1 also includes a solution dispenser 17 (see FIGS. 2 to 4). The details of each part will be described later.

The pretreatment device 1 also includes a tip rack 11 and a test tube rack 12 (see FIG. 1). The pretreatment device 1 also includes a PC control unit (not shown) that controls the operation of each component and mechanism of the device.

The pretreatment device 1 also includes a transport section 13 that transports a stomacher bag 15 to which a clip section 16, which will be described later, is attached (see Figures 1, 3, and 4). The configuration including the pretreatment device 1 and the clip section 16 corresponds to an example of a pretreatment mechanism for microorganism testing to which the present invention is applied.

The pretreatment device 1 also has a frame portion 14 (see FIG. 2) and a protective cover (not shown), and the frame portion 14 and the protective cover form the outer shape of the upper portion of the pretreatment device 1. These members also isolate the internal space of the device from the outside.

The pretreatment device 1 is configured so that the above-mentioned components are arranged and housed in an internal space covered by a frame portion 14 and a protective cover, and the cleanliness of the internal space can be increased using a HEPA filter or the like.

The pretreatment device 1 is also provided with an opening/closing section (not shown), allowing the operator to carry in and out stomacher bags, film culture media, chips, test tubes, etc. between the inside and outside of the device.

[Explanation of each component]
Next, each component of the pretreatment device 1 will be described.
[Stand]
The stand 2 is a section for arranging a plurality of stomacher bags 15 containing samples therein (see Figs. 1 to 4 and 6). The stomacher bags 15 containing samples to be subjected to microbial testing are set on the stand 2, and the stomacher bags 15 are subjected to processes carried out by each component of the pretreatment device 1.

The stomacher bag 15 referred to here is the component equivalent to the storage bag in the claims of this application.

The stomacher bag 15 used in the pretreatment device 1 is a plastic bag with an opening at the top, and the inside is sterilized (see Figures 5(a) and 5(b)).

The stomacher bag 15 is also provided with a filter 150, and the internal space of the stomacher bag 15 is partitioned by the filter 150 into a sample area 151 and a filtration area 152.

The sample area 151 of the stomacher bag 15 is a space in which the sample to be tested is stored. The filter 150 is a filtering member that is permeable to a diluted solution such as a sterile phosphate buffer solution and that captures particles of a certain size or larger, such as sample pieces and foreign matter mixed with the sample. The filtering area 152 is a portion that receives the diluted solution injected by the stomacher dispenser 4 and the diluted solution that has permeated the filter 150.

A clip portion 16 is attached to the upper portion of the stomacher bag 15 (see Figs. 5(a) and 5(b)). The clip portion 16 clamps and fixes the upper portion of the stomacher bag 15 from both sides, and is the portion that is gripped by the conveying portion 13 when the conveying portion 13 conveys the stomacher bag 15. The clip portion 16 referred to here is the member that corresponds to the clip portion in the claims of this application.

The clip portion 16 also has a collection port 160 formed on its end side. This collection port 160 is formed in communication with the filtration region 152 of the stomacher bag 15, and is an opening that is used when injecting the diluted solution into the stomacher bag 15 or when collecting the diluted solution from the inside after stomacher processing.

The sampling port 160 referred to here is the component that corresponds to the sampling port in the claims of this application.

Here, it is not necessary to provide a filter 150 in the stomacher bag 15, and in the pretreatment device 1 of the present invention, it is also possible to use a stomacher bag without a filter 150. In this case, too, a clip part 16 is attached to the opening at the upper end of the stomacher bag. However, by using the filter 150 to collect particles above a certain size, it becomes difficult for sample pieces and the like to be contained in the solution after stomacher processing, and this can reduce problems that affect the accuracy of the stepwise dilution in the subsequent process and the inoculation of the culture medium.

As shown in FIG. 5, a first protrusion 161 is formed on the end of the clip portion 16 where the collection port 160 is provided, and a second protrusion 162 is formed on the opposite end.

These first protrusions 161 and second protrusions 162 fit into fitting parts (reference numerals omitted) provided on the stand part 2, and become parts that determine the placement position, height, and orientation of each clip part 16 and stomacher bag 15 on the stand part 2. In addition, the conveying part 13 moves to the position determined here and grips the clip part 16.

Therefore, in the stand 2, multiple stomacher bags 15 are stored and arranged at a fixed position, height, and orientation (in FIG. 6(b), the collection port 160 is oriented downward in the figure). The balance 3 and stomacher 5 are also provided with mating parts corresponding to the first convex part 161 and the second convex part 162, and the arrangement position, height, and orientation of the stomacher bags 15 are specified.

Here, it is not necessary that the collection port 160 is formed on the end side of the clip part 16, and it is sufficient that an opening is formed at any position on the clip part 16 through which a solution can be injected or collected. However, it is preferable that the collection port 160 is formed on the end side of the clip part 16, because this makes it easier to collect the sample solution when a filter 150 is provided on the stomacher bag 15 and a filtration area 152 is formed inside the filter 150.

Furthermore, it is not necessary that the first protrusion 161 and the second protrusion 162 are formed on both ends of the clip portion 16. As long as the stand portion 2, the balance 3, and the stomacher 5 are structured in such a way that the placement position, height, and orientation of the stomacher bag 15 can be specified, the specific structure is not particularly limited.

[Scales]
The balance 3 is a member that measures the total mass of the stomacher bag 15 including the clip portion 16 and the sample stored in the sample area 151 inside the stomacher bag 15 (see FIG. 1). That is, the mass of each sample is measured by the balance 3. The balance 3 here is a member that corresponds to the weighing portion in the claims of this application.

The balance 3 is also composed of a holding part that holds the stomacher bag 15, and a measuring part that measures the mass of the stomacher bag 15 (including the clip part 16 and the sample) held by the holding part (reference numbers omitted). The holding part is provided with fitting parts that correspond to the first convex part 161 and the second convex part 162, and holds the stomacher bag 15 via these parts.

In addition, in the pretreatment device 1, the mass of the stomacher bag 15 including the clip portion 16 to be used is recorded in advance (empty mass), and the PC control unit (not shown) is configured to subtract this empty mass from the measured value measured by the balance 3 to calculate the mass of each sample.

The stomacher dispenser 4 is a component that injects a dilute solution such as a sterile phosphate buffer solution into the stomacher bag 15 whose mass has been measured by the balance 3 (see Figures 1, 3, and 4).

This stomacher dispenser 4 is composed of a tank that contains the diluted solution, an injection section that communicates with the tank and discharges the diluted solution, and a drive section that moves the entire device so that the injection section is positioned at the collection port 160 of the stomacher bag 15 held in the holding section of the balance 3 (not shown).

The PC control unit controls the amount of diluted solution injected from the injection unit of the stomacher dispenser 4 into the collection port 160 so that the sample mass measured by the measurement unit of the balance 3 is diluted 10 times. In other words, the stomacher dispenser 4 is configured to automatically inject diluted solution to a predetermined dilution ratio according to the mass of each sample.

The stomacher dispenser 4 and the PC control unit referred to here are components that correspond to the sample preparation unit in the claims of this application. Also, 10-fold dilution means that, for example, if the mass of the sample is 10 g, 90 g of diluted solution is injected to dilute the sample to a total of 100 g.

In addition, the stomacher bag 15 containing the sample placed on the stand section 2 is configured to be transported to the holding section of the balance 3 via the transport section 13.

Here, the amount of diluted solution that the stomacher dispenser 4 injects into the collection port is not necessarily set to a 10-fold dilution of the mass of the sample measured by the measuring unit of the balance 3, and it is possible to change the dilution ratio according to the conditions of the microbiological test, etc.

[Stomacher]
The stomacher 5 is a member that applies a pressing force to the stomacher bag 15 containing the sample and the dilution solution, crushing and dispersing the sample to suspend it, thereby extracting the bacteria in the sample into the dilution solution (see Figs. 1 to 4 and 7). The stomacher 5 referred to here is a member that corresponds to the homogenizer in the claims of this application.

The stomacher 5 also has a bag placement section 50 for placing and fixing the stomacher bag 15, and paddle sections 51 and 52 for applying a pressing force to the stomacher bag 15 fixed to the bag placement section 50 (see Figures 7(a) and 7(b)).

The bag placement section 50 referred to here is the component that corresponds to the bag placement section in the present claims, and the paddle section 51 and the paddle section 52 referred to here are the components that correspond to the crushing section in the present claims.

In addition, one stomacher bag 15 can be placed and fixed in the bag placement section 50. The bag placement section 50 has a closing roller section 500 that clamps and fixes the upper part of the stomacher bag 15 from both sides, and a receiving roller section 501. Note that the closing roller section 500 and the receiving roller section 501 referred to here are members that correspond to the closing mechanism in the claims of this application.

When the conveying unit 13 places the stomacher bag 15 in the bag placement unit 50, the movement distance of the paddle unit 51 and the paddle unit 52 in the reciprocating motion is controlled via the PC control unit as described below, and the two pressing surfaces 510 and 520 press the stomacher bag 15 into which the diluted solution has been dispensed, raising the liquid level of the diluted solution while removing a certain amount of air inside the stomacher bag 15. The blocking roller unit 500 and the receiving roller unit 501 are members that clamp the upper part of the stomacher bag 15 from both sides to block it.

In addition, the bag placement section 50 is provided with a fitting section (not shown) that corresponds to the first protrusion 161 and the second protrusion 162 of the clip section 16, and the placement position, height, and orientation of the stomacher bag 15 are specified.

The paddle section 51 and the paddle section 52 are connected to a motor via a paddle shaft (reference number omitted) and are configured to be capable of reciprocating motion in the linear direction connecting the main body 53 of the stomacher 5 and the bag placement section 50 (the direction in which the paddle shaft extends).

The tip surfaces of the paddle parts 51 and 52 are provided with plate-shaped pressing surfaces 510 and 520, respectively, which come into contact with the stomacher bag 15 and apply a pressing force. Note that the pressing surfaces 510 and 520 referred to here are members that correspond to the pressing surfaces in the claims of this application.

The pressing surface 510 and the pressing surface 520 have a surface that is approximately parallel to the side surface of the stomacher bag 50 fixed to the bag placement section 50. The pressing surface 510 and the pressing surface 520 are also provided at the same height position in the vertical direction.

Here, the structure of the stomacher 5 is not necessarily limited to one having a bag placement section 50 and two paddle sections 51 and 52, and various mechanisms can be adopted as long as the device is capable of applying a pressing force to the sample in the stomacher bag to crush, disperse, and suspend the sample. For example, instead of the paddle section, a roller mechanism can be adopted as the crushing section, in which the stomacher bag 15 is sandwiched between two rotating rollers and a pressing force is applied while rotating. However, as described below, it is preferable that the stomacher 5 has two paddle sections 51 and 52, since the movement of the two paddle sections makes it easier to collect the sample solution after stomacher processing.

The number of paddle parts in the stomacher 5 is not necessarily limited to two, and it is also possible to have a structure with a single paddle part or three or more paddle parts. However, as described below, it is preferable to have at least two paddle parts, because this allows the pressure surfaces of the two paddle parts to be aligned when collecting the sample solution after stomacher processing, thereby allowing the liquid level of the sample solution to rise uniformly.

The reciprocating motion of the paddle parts 51 and 52 is also configured so that the speed of the reciprocating motion can be controlled via the PC control unit. This makes it easier to make the paddle parts reciprocate at a constant speed and maintain consistent sample disruption conditions even if the load applied when pressing the paddle parts 51 and 52 changes depending on the type of sample, the disruption state, the amount of diluted solution injected, etc. As a result, errors associated with the disruption conditions are reduced, making it easier to obtain systematic data in the culture test results.

In addition, by controlling the speed of the reciprocating motion of the paddle parts 51 and 52, the timing at which the paddle parts 51 and 52 press against one stomacher bag 15 can be made different, and the two paddle parts 51 and 52 can press against the stomacher bag 15 alternately. As a result, the efficiency of crushing the sample can be improved.

In addition, the speed of the reciprocating motion can be controlled to align the positions of the two pressing surfaces 510 and 520 along the direction of movement to press the stomacher bag 15.

The reciprocating motion of the paddle parts 51 and 52 is configured so that the distance traveled by the paddle parts 51 and 52 during the reciprocating motion can be controlled via the PC control unit. That is, the positions of the two pressing surfaces 510 and 520 along the direction of movement can be changed. The distance traveled by the paddle parts 51 and 52 is controlled so that they move to a set position according to the amount of diluted solution injected by the stomacher dispenser 4.

This allows the positions of the pressing surfaces 510 and 520 to be changed in the direction of movement of the two paddle parts in accordance with the amount of diluted solution, changing the force with which the stomacher bag 15 is pressed, and adjusting the liquid level of the diluted solution inside.

By controlling the reciprocating motion of the paddle section in this way, the liquid level of the diluted solution in the stomacher bag 15 can be adjusted when the diluted solution in which the crushed sample is suspended in the stomacher bag 15 that has undergone stomacher processing is collected by the solution dispenser 17 described below.

For more details, see FIG. 8. As shown in FIG. 8(a), the positions of the pressing surfaces 510 and 520 of the paddle parts are aligned in the direction indicated by the symbol X in the figure with respect to the stomacher bag 15 that has undergone stomacher processing, and the paddle parts are moved toward the stomacher bag 15 at the same speed.

As shown in FIG. 8(b), the pressing surfaces 510 and 520 of each paddle portion move to a position set according to the amount of diluted solution injected by the stomacher dispenser 4 while abutting against the side of the stomacher bag 15 with their positions aligned in the direction indicated by the symbol X in the figure.

By this movement of each paddle part, the height position of the liquid surface of the diluted solution in the stomacher bag 15 rises from the position of symbol L1 shown in FIG. 8(a) to the position of symbol L2 shown in FIG. 8(b). This position of symbol L2 is the height position (range) at which the tip of the pipette part of the solution dispenser 17 can pass through the collection port 16 of the clip part 16 and collect a certain amount of diluted solution.

In addition, in the direction indicated by the symbol X in Figures 8(a) and 8(b), the pressing surfaces 510 and 520 of each paddle portion are aligned, so that a uniform pressing force can be applied to the side of one stomacher bag 15. As a result, the liquid level of the diluted solution can be raised to the desired position (L2) without variation in the liquid level in the internal space of the stomacher bag 15.

Here, when collecting the sample solution after stomacher processing, it is not necessarily necessary to use the movement of the two paddle parts to raise the liquid level of the sample solution. It is also possible to adopt a mode in which a mechanism that applies a pressing force to the stomacher bag 15 is provided separately from the paddle parts to raise the liquid level of the sample solution.

[Transport section]
The conveying unit 13 is a mechanism for conveying the stomacher bag 15 having the clip unit 16 attached thereto between the stand unit 2, the balance 3, and the stomacher 5 (see Figs. 1, 3, and 4). The conveying unit 13 is a member that corresponds to the conveying mechanism in the present claims.

The conveying unit 13 also has a gripping arm 130 (see Figures 3 and 4) that grips the stomacher bag 15 by gripping the clip portion 16, a conveying rail 131, and a drive unit 132 (see Figures 1, 3, and 4) that moves the gripping arm 130 along the conveying rail 131 and also moves the gripping arm 130 in the vertical direction.

The opening and closing operation of the arm portion (reference number omitted) that grips the clip portion of the gripping arm 130, the movement of the gripping arm 130 along the conveying rail 131, and the movement of the gripping arm 130 in the vertical direction are controlled by the PC control unit.

Here, the transport unit 13 does not necessarily have to have a gripping arm 130, a transport rail 131, and a drive unit 132, and the specific configuration is not particularly limited as long as the stomacher bag 15 with the clip unit 16 attached can be transported to the desired position.

[Solution dispenser]
The solution dispenser 17 is a member that collects a sample solution in which the crushed sample is suspended from the stomacher bag 15 placed in the bag placement section 50 of the stomacher 5 after the stomacher process, transports the sample solution, and injects the collected sample solution into a test tube containing a dilution solution for the next step of serial dilution. The solution dispenser 17 is also a member that collects and dispenses the solution during serial dilution, and inoculates the serially diluted sample solution into a culture medium. The solution dispenser 17 here corresponds to the sample collection section in the claims of this application.

The solution dispenser 17 is also composed of a pipette unit to which a disposable tip can be attached and detached, and a drive unit that moves the position of the pipette unit (reference numerals omitted).

The horizontal and vertical movements of the drive unit are controlled via the PC control unit so that it can move to each of the positions of the tip rack 11 on which the sterilized tips are arranged, the sampling port 160 of the clip part 16 of the stomacher bag 15 arranged in the bag arrangement part 50, the dilution test tube set in the test tube mixer 6 described below, the position where the suction part 70 of the film opening/closing part 7 lifts the protective film 102, and the tip disposal part where used tips are discarded.

In addition, the pipette unit's operations, such as attaching and detaching tips, sucking up solutions, and dispensing solutions, are all controlled via a PC control unit.

[Test tube mixer]
The test tube mixer 6 is a member that dispenses a dilution solution for the stepwise dilution into a test tube and cooperates with the solution dispenser 17 to stepwise dilute the diluted solution in which the crushed sample collected from the stomacher bag 15 is suspended (see Figs. 1, 2 and 4). The solution dispenser 17 and the test tube mixer 6 are members that correspond to the stepwise dilution unit.

The test tube mixer 6 also has a test tube holding section (reference number omitted) that holds the test tubes during serial dilution, a tank (reference number omitted) that contains the diluted solution, a diluent dispensing section (reference number omitted) that communicates with the tank and dispenses a predetermined amount of the diluted solution into an empty test tube held in the test tube holding section, and a transport hand unit 8 (see Figure 1) that transports the test tubes from the test tube rack 12.

The test tube mixer 6 also has a stirring section that vibrates the test tube held by the test tube holder to stir the solution in the test tube, and a tip disposal section that discards used tips from the pipette section of the solution dispenser 17 (reference numbers omitted).

The test tube mixer 6 is also configured to hold two empty test tubes in the test tube holder, and dispense a fixed amount of a sterile phosphate buffer solution or the like into these empty test tubes to prepare 100-fold and 1000-fold diluted solutions based on the original sample.

That is, the initial sample is diluted 10 times (1/10 sample liquid) with the diluted solution injected by the balance 3, and then further diluted in stages in the test tube mixer 6 to 100 times (1/100 sample liquid) and 1000 times (1/1000 sample liquid).

The solution dispenser 17 is also configured to dispense the diluted solution collected from the stomacher bag 15 into a diluted solution (100-fold dilution), collect the solution after stirring, dispense it into a further diluted solution (1000-fold dilution), and discard used tips.

The specific structure of the test tube mixer 6 is not particularly limited, and various mechanisms may be adopted, so long as the test tube mixer 6 cooperates with the solution dispenser 17 to automatically perform stepwise dilution in a test tube containing a dilution solution.

[Film opener, solution dispenser, spreader and medium stocker]
The culture medium stocker 10 is a member on which the film-shaped culture medium is placed before and after use, and is a part for transferring the film-shaped culture medium between a separate moving frame (not shown). An unloading stocker (not shown) is also provided in the culture medium stocker 10. The film-shaped culture medium after being inoculated with the sample solution is automatically unloaded into the unloading stocker, and is configured to be unloaded together with the unloading stocker to the outside of the pretreatment device 1.

In addition, in the pretreatment device 1, a film-like medium 100 (see FIG. 9) is used as a medium for inoculating the sample solution and performing a microbial test. The film-like medium 100 is composed of a sheet-like medium body 101 containing a medium capable of cultivating microorganisms, and a protective film 102 that covers the medium body (not shown).

The film-like medium 100 referred to here is the film medium in the claims of this application, the medium body 101 referred to here is the film medium body in the claims of this application, and further, the protective film 102 referred to here is the protective film in the claims of this application.

In addition, since the film-like medium 100 is smaller in overall size and thickness than plate-like medium, it is possible to set several tens of sheets in the medium stocker 10. Note that the film-like medium 100 can be a known film-like medium for microorganism testing, and a detailed description of its structure will be omitted.

The film opener 7 is a member through which the film-like medium 100 before use is transported and positioned, and before inoculation with the sample solution, it lifts the protective film 102 to make the medium body 101 in a state in which the sample solution can be inoculated. In addition, after the medium body 101 is inoculated with the sample solution, the film opener 7 is a member that lowers the protective film 102 that was lifted, so that the medium body 101 is covered with the protective film 102 again.

The film opening/closing device 7 referred to here is the film lifting mechanism in the present claims.

The film opener 7 also has a suction unit 70 that sucks and grips the protective film 102. That is, the protective film 102 can be lifted by suction with the suction unit 70. Also, the suction of the suction unit 70 can be stopped to lower the protective film 102 from its lifted state.

The film opening/closing device 7 is provided with multiple suction units 70 and is configured to be able to process multiple film-shaped culture media 100 at once (see Figure 9). In addition, the operation of the film opening/closing device 7 is controlled by a PC control unit.

Here, the film opening/closing unit 7 does not necessarily have to have a suction unit 70, and the mechanism that performs this operation is not particularly limited as long as it can lift and lower the protective film 102 of the film-like culture medium 100 at the desired timing.

The solution dispenser 17 is a member that inoculates the sample solution that has been serially diluted in the test tube mixer 6 toward the culture medium body 102 while the suction part 70 of the film opening/closing part 7 is lifting the protective film 102 of the film-like culture medium 100.

The spreader machine 9 is a member that performs a spreading process in which the solution dispenser 17 inoculates the sample solution and the film opening/closing unit 7 lowers the protective film 102 onto the medium body 101, and then presses the protective film 102 to uniformly spread the sample solution over the medium body 101 (see FIG. 11(d)).

The spreader machine 9 is configured so that the moving frame carrying the multiple film-like culture media 100 inoculated with the sample solution is driven vertically while moving below the spreader machine 9, applying a pressing force from above the protective film 102.

The multiple film-like culture media 100 spread by the spreader machine 9 are transported to the culture medium stocker 10 while still placed on the moving frame, and are automatically transported to the unloading stocker.

The pretreatment device for microorganism testing of the present invention is not limited to having a device mechanism for film-like culture media, as in the above-mentioned pretreatment device 1, but can also have a device mechanism for processing plate-like culture media. In this case, a culture medium stocker, plate opening and closing device, and spreader machine suitable for automatically processing plate-like culture media are provided.

The pretreatment device 1 also includes a printing mechanism (not shown). The printing mechanism prints identification information for identifying each film-like medium 100 at a predetermined position on the film-like medium. The identification information includes, for example, the type of sample, information on the supplier, the date and time of receipt, the date of testing, the specimen number, the name of the operator, the test item, the dilution multiplier, the n-number of tests, etc.

The printing mechanism is also configured to be able to print on the film-like culture medium 100 both before and after the sample solution is inoculated.

The printing mechanism is controlled by the PC control unit in terms of the content of the identification information and the selection of the film-like medium to be printed. The printing mechanism referred to here is the component that corresponds to the identification information imparting mechanism in the claims of this application.

Here, the identification information imparting mechanism in the present invention is not limited to a printing mechanism, and various mechanisms can be used as long as they can impart information that can identify the culture medium. For example, a printing mechanism such as an inkjet, laser, or thermal printer, or a seal imparting mechanism that affixes a seal can be used.

The PC control unit (not shown) is a part that controls the operation of each component and mechanism of the pretreatment device 1. In addition to the above-mentioned controls, the PC control unit can also control, for example, the setting of the time for the stomacher process by the stomacher 5, the amount of sample solution that the solution dispenser 17 inoculates into the film-like medium 100, etc.

Here, the operation of each component and mechanism of the pretreatment device 1 does not necessarily need to be controlled by a PC control unit, and each control can also be performed using a PLC control unit, for example.

Next, as an example of a pretreatment method for a microorganism test to which the present invention is applied, a specific example of a sample pretreatment method using the above-mentioned pretreatment device 1 will be described. Note that the content described below is merely an example, and the pretreatment method for a microorganism test to which the present invention is applied can be modified as appropriate.

Figures 10 and 11 show an outline of the sample processing flow in each component using the pretreatment device 1.

First, in the processing method using the pretreatment device 1, various types of objects can be handled as test samples for detecting the presence or absence of microorganisms or the number of bacteria, such as food, pharmaceuticals, cosmetics, chemical products, environmental water, soil, etc.

For example, in food testing, the samples would be vegetables, fresh fish, processed foods, and bento ingredients from the food section. Food testing generally involves measuring the viable bacteria count and coliform bacteria count. The sample to be tested is prepared into a size that can be stored in the stomacher bag 15 (e.g., 10 to 25 g) by, for example, dividing it into smaller pieces.

Then, the sample that has reached a certain size is placed in the sample area 151 inside the stomacher bag 15 (see FIG. 10(a)). After the sample is placed, the opening at the top of the stomacher bag 15 is clamped and fixed with a clip 16, and the opening of the stomacher bag 15 is closed (see FIG. 10(b)).

The stomacher bags 15 are prepared according to the number of samples to be tested. The stomacher bags 15 containing the samples are then set on the stand 2 of the pretreatment device 1 (see Figure 10 (c)).

The various consumables (dilution solution, chips, film-like medium, etc.) to be used are set inside the pretreatment device 1. The operator also sets the various conditions (time for stomacher processing, dilution ratio, type of medium for viable cell count measurement and coliform bacteria measurement, n number, identification information to be printed, etc.) controlled by the PC control unit, and executes automatic operation. Note that the flow up to this point is performed manually by the operator.

From this point onwards, with multiple Stomacher bags 15 placed on the stand 2, the following operations are all performed automatically via the pre-processing device 1: weighing the sample, injecting the dilution solution, Stomacher processing, sampling the sample solution after Stomacher processing, serial dilution of the sample solution, inoculation of the sample solution into the film-like medium, spreading, printing of identification information on the film-like medium, and transport to the discharge stocker.

When an operator performs automatic operation of the pretreatment device 1, the stomacher bag 15 containing the sample placed on the stand 2 is transported to the balance 3 by the transport unit 13. The transport arm 130 of the transport unit 13 grasps the clip portion 16, and the stomacher bag 15 is transported to the holding portion of the balance 3 (see FIG. 10(d)).

The balance 3 also measures the mass of the stomacher bag 15 held in the holder (see FIG. 10(d)). The balance 3 measures the total mass of the stomacher bag 15 and the sample, and the PC control unit subtracts the previously recorded mass of the stomacher bag 15 alone to calculate the mass of the sample alone. For example, assume that the mass of the sample is calculated to be 10 g.

Then, the stomacher dispenser 4 moves toward the stomacher bag 15 held by the holder of the balance 3. The stomacher dispenser 4 moves so that its injection part is at the position of the collection port of the clip part 16 (see FIG. 10(e)), and dispenses sterilized phosphate buffer so as to dilute the sample by 10 times based on the mass of the sample. Here, 90 g of sterilized phosphate buffer is added to 10 g of sample.

In this way, the amount of sterile phosphate buffer is automatically calculated to achieve a 10-fold dilution based on the mass of the sample measured by the balance 3, and the stomacher dispenser 4 injects it into the stomacher bag 15.

The stomacher bag 15 into which the sterile phosphate buffer solution has been injected is transported to the stomacher 5 by the transport unit 13. Even during this transport, the transport arm 130 grips the clip unit 16, allowing for stable transport.

Then, the transport unit 13 transports the stomacher bag 15 to the bag placement unit 50 of the stomacher 5, and the stomacher bag 15 is placed in the bag placement unit 50 (see FIG. 10(f)). Then, the pressing surfaces 510 and 520 of each paddle unit come into contact with the stomacher bag 15 and, while pressing the side surface, the pressing surfaces 510 and 520 move to a position set according to the amount of sterile phosphate buffer solution dispensed by the stomacher dispenser 4, and the air in the stomacher bag 15 is removed from the top.

When the pressing surface 510 and the pressing surface 520 reach the set position, the blocking roller unit 500 advances toward the stomacher bag 15, and the upper part of the stomacher bag 15 is sandwiched between the blocking roller unit 500 and the receiving roller unit 501, blocking the upper part of the stomacher bag 15. This prevents the diluted solution from spilling out from the upper part of the stomacher bag 15 during stomacher processing.

In addition, in the stomacher 5, the closing roller section 500 and the receiving roller section 501 clamp and fix the upper part of the stomacher bag 15, and then the two paddle sections 51 and 52 move back and forth alternately to apply a pressing force to the stomacher bag 15.

The stomacher process using each paddle crushes and disperses the sample in the sterile phosphate buffer solution, suspending it and extracting the bacteria in the sample into the solution. The stomacher process is performed under set conditions (processing time and paddle speed).

When the stomacher process in the stomacher 5 is completed, the two paddle parts 51 and 52 align the positions of the pressing surfaces 510 and 520 in the direction in which each paddle part faces the stomacher bag 15, and move toward the stomacher bag 15 (see FIG. 10(g)).

Then, the pressing surfaces 510 and 520 of each paddle portion come into contact with the stomacher bag 15 and, while pressing the side surface of the stomacher bag 15, the pressing surfaces 510 and 520 move to a position set according to the amount of sterile phosphate buffer solution dispensed by the stomacher dispenser 4 (see FIG. 10(h)).

In this way, the pressing surfaces 510 and 520 move to positions set according to the volume of the sterile phosphate buffer solution and press the stomacher bag 15, thereby raising the height of the liquid level inside to a position where it can be collected by the tip of the pipette part of the solution dispenser 17 (the position indicated by the symbol L2 in FIG. 10(h)).

In addition, by moving the pressing surfaces 510 and 520 in unison, a uniform pressing force is applied to the stomacher bag 15, and the liquid level can be raised to the desired position (L2) without variation in the liquid level. In FIG. 10(g), the height position of the liquid level before the rise is indicated by the symbol L1.

In addition, with the liquid level inside the stomacher bag 15 raised, the pipette part of the solution dispenser 17 moves to the position of the sampling port 160 of the clip part 16, and 1 ml of sample solution is sampled with the tip of the pipette part.

Next, the solution dispenser 17 that has collected the sample solution moves to the test tube mixer 6 (see FIG. 11(a)). Two test tubes with 9 ml of sterile phosphate buffer solution dispensed therein are placed in the test tube mixer 6, one for a 1/100 dilution and the other for a 1/1000 dilution.

The solution dispenser 17 dispenses the sample solution into the test tube for 1/100 dilution held in the test tube holder. After dispensing the sample solution, the test tube is stirred by the stirring part of the test tube mixer 6. This operation prepares a diluted solution in which the sample is diluted 1/100.

Then, after replacing the tip, the solution dispenser 17 uses the pipette unit to collect 1 ml of the diluted solution diluted 1/100, and dispenses the sample solution into a test tube for dilution at 1/1000. After dispensing the sample solution, the test tube is stirred by the stirring unit of the test tube mixer 6. This operation prepares a diluted solution in which the sample is diluted 1/1000. In this way, the solution dispenser 17 and the test tube mixer 6 work together to perform stepwise dilution.

In addition, multiple film-like culture media 100 are supplied from the culture medium stocker 10 to the position of the film opening/closing device 7 via the moving frame. The film opening/closing device 7 sucks and grips the protective film 102 of the film-like culture medium 100 with the suction part 70, and lifts the protective film 102 (see FIG. 11(b)).

Then, the solution dispenser 17 uses its pipette to collect the diluted solution (1/100 dilution or 1/1000 dilution) in the test tube held by the test tube mixer 6, and moves to the position of the medium body 101 with the protective film 102 lifted. The solution dispenser 17 drops 1 ml of the sample solution collected by the pipette into the medium body 101 (see FIG. 11(c)).

In addition, in the film-like medium 100 onto which the sample solution has been dropped, the film opener 7 lowers the protective film 102, so that the medium body 101 is covered with the protective film 102. Furthermore, the spreader machine 9 presses the protective film 102 from above (in the direction of the arrow marked with the symbol Y in FIG. 11(d)), spreading the sample solution evenly over the medium body 101 (spreader process) (see FIG. 11(d)).

The solution dispenser 17 inoculates the film-like medium 100 with the sample solution as many times as necessary, according to the set conditions, depending on the number of tests to be performed and the concentration of the diluted solution. Identification information is also printed on the film-like medium 100 via the printing mechanism.

Next, the film-like medium 100 that has been subjected to the spreader process is transported to the medium stock 10 via the moving frame and is automatically transported to the output stocker (see FIG. 11(e)).

By following the above steps, the pretreatment device 1 automatically inoculates the film-like medium 100 from the stomacher bag 15 containing the sample. The film-like medium 100 placed in the discharge stocker is transported outside the pretreatment device 1 and cultured in an incubator, and then used to confirm colonies after culture.

In this way, in the pretreatment device 1, the sample to be tested is placed in the stomacher bag 15 and set on the stand 2 of the pretreatment device 1. The subsequent operations are then carried out automatically, and the film-like medium can be prepared before the cultivation stage without the need for an operator.

In other words, the operator only needs to perform the simple operation of setting the stomacher bag 15 containing the sample and consumables such as the dilution solution, the chip, and the film-like medium 100 in the pretreatment device, making it possible to carry out microbial testing very efficiently.

In addition, the pretreatment device 1 automates each task that previously required manual intervention and resulted in errors, such as weighing the sample, diluting the diluted solution or dispensing the diluted solution, serial dilution, inoculating the sample solution into culture medium, and spreader processing, allowing for accurate processing and making it easier to obtain test results with good reproducibility.

As described above, the pretreatment device for microorganism testing of the present invention can automate the pretreatment of samples in microorganism testing, and enables accurate treatment with high reproducibility.
Furthermore, the pretreatment mechanism for microorganism testing of the present invention can automate the pretreatment of samples in microorganism testing, enabling accurate treatment with high reproducibility.
Furthermore, the pretreatment method for a microorganism test of the present invention can automate the pretreatment of a sample in a microorganism test, enabling accurate treatment with high reproducibility.

The invention made by the inventor has been specifically described above based on the embodiment, but it goes without saying that the invention is not limited to the above embodiment and can be modified in various ways without departing from the gist of the invention.

LIST OF SYMBOLS 1 Pretreatment device 2 Stand section 3 Balance 4 Stomacher dispensing machine 5 Stomacher 50 Bag placement section 500 Closing roller section 501 Receiving roller section 51 Paddle section 510 Pressing surface 52 Paddle section 520 Pressing surface 53 Main body 6 Test tube mixer 60 Probe 61 Contact section 7 Film opener 70 Suction section 8 Transport hand unit 9 Spreader machine 10 Culture medium stocker 11 Tip rack 12 Test tube rack 13 Transport section 130 Grip arm 131 Transport rail 132 Drive section 14 Frame section 15 Stomacher bag 150 Filter 151 Sample area 152 Filtration area 16 Clip section 160 Collection port 161 First convex section 162 Second convex section 17 Solution dispensing machine 100 Film-like medium 101 Medium body 102 Protective film

Claims (15)

A pretreatment device for a microorganism test automatically performs a series of operations, which are to inject a diluting solution into a storage bag in which a predetermined sample is stored, to crush and disperse the predetermined sample by pressing the storage bag, and to collect the suspended sample,
A conveying mechanism for conveying the storage bag;
A weighing unit that weighs the mass of the predetermined sample and the storage bag;
a sample preparation unit that injects the diluted solution into the storage bag so as to obtain a predetermined dilution ratio according to the value measured by the weighing unit, thereby preparing the predetermined sample;
a homogenizer having a bag arrangement section in which a storage bag containing the sample prepared in the sample preparation section is fixedly arranged, and a crushing section that presses the storage bag arranged in the bag arrangement section to crush, disperse, and suspend the prepared sample;
a sample collection section for collecting the sample suspended in the crushing section. 2. The pretreatment device for microorganism testing according to claim 1, further comprising a control mechanism that adjusts the liquid level of the suspended sample in the storage bag to a certain range of height depending on the amount of the dilution solution injected into the storage bag when the sample collection unit collects the suspended sample. The crushing unit has a pressing surface formed in a direction substantially parallel to a side surface of the storage bag placed in the bag placement unit, and is configured to be capable of reciprocating motion along a direction connecting the pressing surface and the side surface of the storage bag,
The pretreatment device for microorganism testing according to claim 2 , wherein the control mechanism adjusts the liquid level by controlling a position of the pressing surface in a direction in which the pressing surface faces a side surface of the storage bag. When the storage bag is placed in the bag placement section, the control mechanism controls the position of the pressing surface in a direction in which the pressing surface faces the side surface of the storage bag to adjust the liquid level, and causes the pressing surface to press the storage bag to remove air from an internal space of the storage bag from an upper portion of the storage bag,
The pretreatment device for microorganism testing according to claim 3, wherein the bag placement section has a closing mechanism that clamps an upper portion of the storage bag from both sides and closes the upper portion of the storage bag when the pressing surface presses the storage bag and reaches a predetermined position. The crushing unit is provided in plurality,
The crushing units are arranged in a line along a direction substantially perpendicular to a direction toward a side surface of the storage bag, and each of the pressing surfaces is provided at substantially the same height position in a vertical direction,
The pretreatment device for microorganism testing according to claim 3 or 4, wherein the control mechanism aligns the positions of the plurality of pressing surfaces in a direction in which the pressing surfaces face the side surface of the storage bag. The storage bag has a clip portion attached to an end thereof and having a collection port formed therein that communicates with the inside of the storage bag,
The pretreatment device for microorganism testing according to claim 1 , wherein the transport mechanism transports the storage bag by gripping the clip portion. The clip portion has the collection port formed on its end side,
The pretreatment device for microorganism testing according to claim 6 , wherein the storage bag and the clip unit are positioned so that the sampling port is located at a predetermined position in the sample preparation unit and the sample sampling unit. a serial dilution unit that serially dilutes the suspended sample collected by the sample collection unit with the dilution solution;
The pretreatment device for microorganism testing according to claim 1 , further comprising a sample inoculation unit for inoculating a predetermined medium with the sample solution diluted by the serial dilution unit. The predetermined medium is a film medium having a sheet-like film medium body having a medium capable of culturing a microorganism and a protective film covering the film medium body,
The pretreatment device for microorganism testing according to claim 8 , wherein the sample inoculation unit has a film lifting mechanism that lifts the protective film from the film culture medium body. The pretreatment device for microorganism testing according to claim 8 or 9, further comprising an identification information imparting mechanism for imparting identification information to the predetermined culture medium. A pretreatment mechanism for a microorganism test automatically performs a series of operations, which are to inject a diluting solution into a storage bag containing a predetermined sample, to press the storage bag to crush and disperse the predetermined sample into a suspension, and to collect the suspended sample,
A clip portion is attached to an end of the storage bag and has a collection port that communicates with the inside of the storage bag;
a conveying mechanism that conveys the storage bag via the clip portion;
A weighing unit that weighs the mass of the predetermined sample and the storage bag;
a sample preparation unit that injects the diluted solution into the storage bag from the collection port so as to obtain a predetermined dilution ratio according to the value weighed by the weighing unit, thereby preparing the predetermined sample;
a homogenizer having a bag placement section in which a storage bag containing the sample prepared in the sample preparation section is fixedly placed, and a crushing section that presses the storage bag placed in the bag placement section to crush, disperse, and suspend the prepared sample;
a sampling section for sampling the sample suspended in the crushing section through the sampling port. A pretreatment method for a microorganism test, which automatically performs a series of operations including injecting a diluting solution into a storage bag containing a predetermined sample, pressing the storage bag to crush and disperse the predetermined sample into a suspension, and collecting the suspended sample,
a weighing step of weighing the mass of the predetermined sample and the storage bag;
a sample preparation step of injecting the diluted solution into the storage bag so as to obtain a predetermined dilution ratio according to the value weighed by the weighing unit, thereby preparing the predetermined sample;
A stomacher processing step of pressing a storage bag containing the sample prepared in the sample preparation section to crush, disperse, and suspend the prepared sample;
and a sample collection step of collecting the sample suspended in the stomacher treatment step. The pretreatment method for a microorganism test according to claim 12, wherein the sample collection step includes a control step of adjusting the liquid level of the suspended sample in the storage bag to a certain range of height depending on the amount of the diluted solution injected into the storage bag. The pretreatment method for a microorganism test according to claim 13, wherein the control step comprises: pressing the storage bag using a crushing unit that reciprocates to press the storage bag in the stomacher processing step; and controlling the position of the crushing unit along the direction in which the storage bag is pressed, thereby adjusting the liquid level. A medium for culturing a microorganism by inoculating a sample solution obtained by serially diluting the sample collected in the sample collection step is a film medium having a sheet-like film medium body having a medium capable of culturing a microorganism, and a protective film for covering the film medium body;
The pretreatment device for microorganism testing according to claim 12, 13 or 14, further comprising a film lifting step of lifting the protective film from the film medium body.

Images