JPS6018392B2 - High-yield culture method for microorganisms - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-yield cultivation method for microorganisms, and in particular, to a high-yield cultivation method for microorganisms suitable for high-yield cultivation of microorganisms that metabolize acid or alkaline substances as they grow. Regarding rate culture method.

Conventionally, methods for culturing microorganisms include a method in which the entire amount of a substrate serving as a carbon source is fed before the start of culture, or a method in which a substrate serving as a carbon source is fed in gruel even during the cultivation.

However, in the former method of culturing microorganisms, there is a problem that the growth of microorganisms is inhibited by the presence of a large amount of carbon source at the start of the culture, and in the latter method, the growth of microorganisms is inhibited by the carbon source. Since the concentration can be kept constant, stable culture can be maintained for a long period of time, but because the consumption rate of the carbon source by microorganisms changes greatly, the following problems arise depending on the method of supplying the substrate, which is the carbon source. .

[11] In the method of sequentially or continuously supplying a predetermined amount of substrate, if the amount of substrate supplied cannot keep up with changes in the rate of consumption of carbon sources by microorganisms, an excess or deficiency of carbon sources may occur, resulting in the proliferation of microorganisms. is inhibited.

■ When the carbon source is an organic acid, there is a method of subtracting the carbon source substrate based on the pH of the culture medium. carbon sources are limited.

'3} If the carbon source is neutral, there is a method of supplying the carbon source substrate using the dissolved oxygen concentration as an indicator, but current dissolved oxygen concentration meters have problems such as drift and reduced sensitivity. However, since accurate dissolved oxygen concentration values cannot be obtained, the substrate donor mixture must be prepared precisely.

I can't control it. The present invention is aimed at solving the above-mentioned problems, and is characterized by measuring the amount of a pH adjuster added and controlling the supply rate of a substrate, which is a carbon source, based on the amount added. The present invention provides a high-yield culture method for microorganisms that can achieve high yields.

Embodiments of the present invention will be described with reference to the drawings.

The drawing is a system diagram of a high-yield culturing device for microorganisms according to the present invention, in which a culture tank 10 is rotatably driven by a drive device 11 equipped with a dissolved oxygen concentration adjusting device, for example, a variable rotation speed device. A mechanical wing 12 is rotatably disposed inside the wing 12, and a solenoid valve, for example, for an alkali or acid storage tank is installed on the upper part of the wing 12.
A pH adjustment device 13 provided with a control valve, a substrate supply rate adjustment device such as a variable flow rate pump 14, a pressure adjustment device,
For example, an exhaust flow rate control valve 15 and a pressure measuring device, such as a pressure gauge 16, are installed, and in the middle thereof,
A pH measuring device, for example, a pH electrode 17, a temperature measuring device, for example, a side temperature resistor 18, a dissolved oxygen concentration measuring device,
For example, a dissolved oxygen concentration meter 19 is installed, and a ventilation conduit 20 is connected to the lower part thereof.

Further, a jacket 21 surrounding the culture tank 10 is provided with a temperature control device, for example, a cooling water flow control valve 22. Pressure gauge 16, pH electrode 17, side temperature resistor 18
The dissolved oxygen concentration meter 19 is an analog/digital converter, for example, an A/D converter equipped with a multiplexer and capable of multi-point processing.
are respectively connected to the D converter 23, and the drive devices 1 1
, the pH adjustment device 13, the variable flow rate pump 14, the exhaust flow rate control valve 15, and the cooling water flow rate control valve 22.
The converter 23 is connected to an arithmetic/control/storage/input/output device, for example, a minicomputer 24 with a keyboard. A culture medium 25 is filled in the culture tank 10 and, for example, if the microorganism is aerobic, the culture is started by aeration through the aeration conduit 20.

During culturing, the pH, temperature, and dissolved oxygen concentration of the culture medium 25 and the pressure of the culture tank 10 are measured using the pH electrode 17, the Yosan thermoresistor 18, the dissolved oxygen concentration meter 19, and the pressure gauge 16, and these measured values are measured. After each is converted into a digital value by the A/D converter 23, it is input to the mini-computer 24, where it is compared with each set value that has been input separately, and based on the result, the mini-computer 24 outputs a control output signal to the pH value. Adjustment device 1
3, the cooling water flow rate control valve 22, the drive device 11, and the exhaust flow rate control valve 15, the environmental conditions of the pH of the culture medium 25, temperature, dissolved oxygen concentration, and pressure of the culture tank 10 are Conditions are controlled to favor the growth of microorganisms. In this way, the pH of the medium 25 during cultivation is always controlled to the set value, but at this time, the rate of change of pH is determined by the pH adjustment device required to control the pH of the medium 25 to the set value. 13 to the amount of pH adjuster added to the medium 25.

Therefore, the amount of FH adjuster added is, for example, a fixed amount of pH adjuster added by one solenoid valve of the pH adjuster 13, and the addition frequency is adjusted to the number of times of addition over a certain period of time. P added with one opening of the solenoid valve of the device 13
It is measured by multiplying by a certain amount of the pH adjuster, and based on the measured amount of the pH adjuster added, the minicomputer 24 calculates according to the calculation formula '1, and the minicomputer 24 sends a control output signal to the variable flow rate pump 14. By outputting the substrate, the substrate is supplied to the tower base 25 at an appropriate supply rate. F=C・N・
q......'1} Here, F: Substrate supply rate C: Constant determined by the bacterial species N: Number of additions obtained by integrating the addition frequency of the pH adjuster over a certain period q: One time of the solenoid valve of the pH adjuster P added at valve opening
Fixed amount of H adjuster In such a high-yield culture method for microorganisms, the pH of the medium is proportional to the rate of change in pH when the pH of the medium during cultivation is controlled to always be at the set value.
By controlling the rate of substrate supply to the culture medium depending on the amount of pH adjuster added to bring the pH value to the set value, it is possible to prevent excess or deficiency of carbon source during culture.

As explained above, the present invention measures microorganisms that metabolize acid or alkaline substances as they grow by measuring the amount of a pH adjuster added while controlling the environmental conditions to conditions favorable for the growth of microorganisms. Since this is a high-yield culture method for microorganisms that controls the substrate supply rate based on the amount added, it is possible to prevent excess or deficiency of carbon source during culture, and has the effect of achieving a high yield of microorganisms.

[Brief explanation of drawings]

The drawing explains an embodiment of the present invention, and is a system diagram of a high-yield culturing apparatus for microorganisms in which the present invention is implemented. 10... Culture tank, 11... Drive device,
12...Road Azusa Tsubasa, 13...Bait adjustment device, 14...Variable flow rate pump, 15...
Exhaust flow rate control valve, 16... Pressure gauge, 17...
・pH electrode, 18... Measuring resistor, 19...
... Dissolved oxygen concentration meter, 20 ... Ventilation conduit,
21...Jacket, 22...Cooling water flow rate control valve, 23. ．． ．． ．．・・A/D converter, 24・・
...Minicomputer.

Claims (1)

[Scope of Claims] 1. A method for culturing microorganisms that metabolize acid or alkaline substances as they grow while controlling environmental conditions to conditions favorable for the growth of microorganisms, including measuring the amount of a pH adjuster added, A high-yield culture method for microorganisms, characterized in that the substrate supply rate is controlled based on the amount added. 2. The method according to claim 1, wherein the amount of the pH adjuster added is measured by sequentially adding a known constant amount, and multiplying the addition frequency by the known constant amount by adding up the addition frequency over a certain period of time. High-yield culture method for microorganisms.