JP5465190B2 - Wood vinegar and method for producing the same - Google Patents

Description

The present invention relates to a wood vinegar solution such as a bamboo vinegar solution and a method for producing the same.
More specifically, for example, the purpose of efficiently removing 3,4-Benz [a] pyrene (hereinafter referred to as benzpyrene), which is one of carcinogenic substances, contained in a small amount in bamboo vinegar, for example. In addition, the concentration of benzpyrene in the commercially available bamboo vinegar is clarified, and the present invention relates to a liquid composition such as bamboo vinegar removed by a simple method and a method for producing the same.

  Wood vinegar is the supernatant of dry-distilled liquid that is produced when wood is carbonized. As a typical example, wood vinegar is produced as a by-product during charcoal baking. In the present specification, wood means not only general wood such as bamboo and pine but also general plants including flowers such as vines.

Wood vinegar is a reddish brown to dark brown liquid in appearance. Most of it is moisture, but it contains weak organic acids (such as acetic acid) derived from wood. Other components include alcohols, carbonyl compounds, or aromatic compounds such as phenols and furans.

Benzpyrene is one of polycyclic aromatics having the structure shown in FIG. Previous studies have shown strong potential as a carcinogenic (carcinogenic) substance and are known to be widely distributed mainly in soil and air. The semi-lethal dose LD ₅₀ showing acute toxicity has been determined to be 250 mg / kg from mouse experiments. Although there is no standard value for food in Japan, the EU standard for benzpyrene concentration in food is 1-5 μg / L (1-5 ppb), and the WHO water quality guideline is 0.7 ppb. Because of this, it is also being watched as a concentration management item in Japan [Non-patent Document 1].

On the other hand, a bamboo vinegar solution will be described as an example of a wood vinegar solution.
Bamboo vinegar is a product obtained when bamboo (charcoal) is processed at high temperature. The solution containing about 90% water component contains various organic acids, polyphenols and alcohols, and is antibacterial. It is widely marketed for the purpose of action. However, it has been suggested that the tar component produced in the production process contains polycyclic aromatics including the benzpyrene.

In the bamboo vinegar production methods reported so far, a method for removing benzpyrene by low-temperature distillation and [Patent Documents 1-6] and a method for removing a tar component by filtration using activated carbon have been clarified [ Patent Document 7-11].
On the other hand, the possibility that the commercial product bamboo vinegar still contains benzpyrene cannot be denied.

JP 2005-179245 A JP 2005-15722 A JP 2003-277766 A JP 2002-30926 A JP 2000-44965 A JP-A-9-249886 JP-A-11-269469 JP 2001-348577 A JP 2006-83199 A JP 2002-293733 A JP 2003-292969 A

Ministry of Agriculture, Forestry and Fisheries: Food Safety Risk Profile Sheet http://www.maff.go.jp/j/syouan/seisaku/risk_analysis/priority/pdf/chm_pah.pdg HongZhang, Ming Xue, Zhiyuan Dai, “Determination of polycyclic aromatic hydrocarbons in aquatic products by HPLC-fluorescence” Journal of Food Composition and Analysis, 23 (2010) 469-474 SabineAndree, W.Jira, K.-H.Schwind, H.Wagner, F.Schwagele, “Chemical safety of meat and meat products” Meat Science, 8 6 (2010) 38-48 Silvia A.V. Tfouni, Rita M.D. Machado, Monica C.R. Tomas Wenzl, Rupert Simon, Juliane Kleiner, Elike Anklam, “Analyticalmethods for plysyclic aromatic hydrocarbons (PAHs) in food and the environmentneeded for new food legislation in the European Union” Trends in Analytical Chemistry, 25 (2006) 716-725 Yuta Miyagawa, Chiyoko Tokue, Yasushi Shiihara, Tomizo Miyagawa, “Comparison and mutagenicity of driftwood vinegar odor components using different solvents” Journal of Japan Society for Food Science and Technology 25 (2005) 125-130 Yoshihiko Akakabe, Yuta Tamura, Soota Iwamoto, Miho Takabayashi, Takeshi Nyuugaku, “Volatile organic compounds with characteristic odor in bamboovinegar” Biosscience Biotechnology and Biochnistry 70 (2006) 2797-2799 Jun Mu, Tohru Uehara, Takeshi Furuno, “Effect of bamboo vinegaronregulation of germination and radicle growth of seed plants II: composition fomoso bamboo vinegar at different collection temperature and its effects” Journal of Wood Science, 50 (2004) 70-476 Shih-Guei Fu, Youngmo Yoon, Russell Bazemore, “Aroma-ActiveComponentsin Fermented Bamboo Shoots” Jornal of Agricultural and Food Chemistry 50 (2002) 549-554 Sung Phil Mun Chang Sub Ku, "Pyrolysis GC-MS analysis of tars formedduring the aging of wood and bamboo crude vinegars" Journal of Wood Science 56 (2010) 47-52

  An object of the present invention is to provide a liquid composition in which benzpyrene is removed to 1 ppt (weight ppt, hereinafter the same) or less by purification by a simple technique, and a method for producing the same.

請 Motomeko according to first invention, the content of benzopyrene carcinogenic substance is Der by a tree in vinegar below 1 ppt.
The invention according to 請 Motomeko 2 is a wood vinegar was purified pyroligneous acid before purification is the wood vinegar according to claim 1, wherein the organic acid component containing prior to purification is left without being removed after purification .
The invention according to claim 3 is a method for producing a purified wood vinegar liquid, characterized in that the wood vinegar before purification containing benzpyrene is treated using octadecyl group-bonded silica gel as an adsorbent.
The invention according to claim 4 is a method for producing a purified wood vinegar solution, comprising filling an open column with a slurry-like octadecyl group-bonded silica and then passing the unpurified wood vinegar solution through the column. is there.
The invention according to claim 5 is the method for producing a purified wood vinegar liquid according to claim 4, wherein the surface of the octadecyl group-bonded silica is hydrophilized.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the wood vinegar liquid which can reduce the benzpyrene in a wood vinegar liquid to 20 ppt or less, Furthermore, 1 ppt or less can be provided, without reducing an effective component for a human body.
ADVANTAGE OF THE INVENTION According to this invention, the wood vinegar liquid without the risk of carcinogenesis can be provided.

Benzpyrene structure Schematic diagram of liquid chromatography system Analysis of polycyclic aromatics in liquid chromatography-fluorescence detection Benzpyrene standard (50μL) fluorescence chromatogram (A): 1.0ppb, (B): 10ppt Fluorescence chromatogram of bamboo vinegar 1 ((A) full spectrum, (B) expanded spectrum) Benzpyrene removal effect by simple treatment with ODS silica cartridge Schematic diagram of column switching liquid chromatography Calibration curve for benzpyrene concentration measurement Photo after adsorption of ODS silica batch of commercially available bamboo vinegar sample 3 (A): Untreated, (B): ODS silica 5g used, (C): ODS silica 10g used, (D): ODS silica 20g used, (E) : Conditioned ODS silica 10g Chromatogram after purification by ODS silica batch adsorption (analysis result of commercial sample 3) Schematic diagram of refining bamboo vinegar by the column method Photo before and after purification of commercial bamboo vinegar sample 3 (A): Untreated, (B): After treatment by column method Final chromatogram of commercial bamboo vinegar sample 5 after purification of ODS silica GC-MS system configuration diagram GC-MS Chromatogram of Commercial Bamboo Vinegar Sample 2 (A): First half of elution, (B): Second half of elution GC-MS chromatogram of commercially available bamboo vinegar liquid sample (unpurified) GC-MS chromatogram before and after ODS silica purification of commercial bamboo vinegar sample 5 (A): Before purification, (B): After ODS silica purification (column method)

In this embodiment, the experiment was performed in the following order.
In this embodiment, bamboo vinegar is used as an example of wood vinegar.
・ Measurement of benzpyrene concentration in bamboo vinegar ・ Development of benzpyrene removal method in bamboo vinegar with silica-based adsorbent ・ Preparation of benzpyrene-free sample by the above method ・ Results of analysis of other components

Details of each item will be described below.
-It is effective to use a chromatographic method such as liquid chromatography or gas chromatography as a quantitative analysis method of polycyclic aromatics for measuring benzpyrene concentration in bamboo vinegar . In the quantitative analysis of polycyclic aromatics in foods reported so far, a system mainly combining liquid chromatography and a fluorescence detector is used [Non-patent Documents 2-5]. The liquid chromatography is composed of the apparatus shown in FIG. 2, and each solute separated in the analytical column is detected by various detectors and converted into an electric signal to obtain a separation chart called a chromatogram. At this time, each peak area in the chromatogram depends on the concentration of the detected solute, and the concentration of the target solute can be known by measuring the area value.

  In addition, the fluorescence detector used in the present analysis can obtain higher sensitivity than the ordinary ultraviolet light detection for the substance group having fluorescence. In particular, since polycyclic aromatics are fluorescent substances, the same technique is considered to be effective in the analysis of benzpyrene.

  In FIG. 3, the chromatogram of the polycyclic aromatics in the liquid chromatography-fluorescence detection in a reference was shown. Here, benzpyrene is detected by a peak indicated by an arrow.

In this example, the quantification limit value and detection limit value of benzpyrene are 48 ng / L (48 ppt) and 16 ng / L (16 ppt), respectively. In other references, the limit of quantification in fluorescence detection is several tens of ppt.
Analysis equipment
: Agilent 1100, Agilent 1046A, 20mL loop injector.
Analysis conditions
: Column-C18 column (4.6 mm x 260 mm), temperature -30 ° C, mobile phase-flow rate: 0.8 mL / min, 0-12 min acetonitrile 85-95%; 12-26 min acetonitrile 95%).

On the other hand, among the academic papers [Non-patent Documents 6-10] of bamboo vinegar analysis reported so far, one report shows that the concentration of benzpyrene is 50 ppt or less. Although this concentration is clear from the above-mentioned benzpyrene concentrations in foods in European countries, no lower concentration is mentioned. However, since one of the objects of the present invention is to bring Benzpyrene as close to zero as possible, the optimal analysis conditions in liquid chromatography and a fluorescence detector were searched, and a sampled bamboo vinegar sample (commercial bamboo vinegar sample) The more sensitive analysis conditions in 1) were set. The analysis conditions are described below.

Analyzer <br/> Liquid feed pump: LC-20AD (Shimadzu Corporation)
Autosampler: SIL-20A / 20AC (Shimadzu Corporation)
Column oven: CTO-20A / 20AC (Shimadzu Corporation)
Detector: RF-20A (Shimadzu Corporation)

Analysis conditions <br/> Analysis column: VP-ODS (150mmx4.6mmi.d.)
Mobile phase: acetonitrile / 10 mM phosphate buffer = 8/2
Flow rate: 0.8 mL / min, Isocratic mode
Evaluation temperature: 40 ℃
Detection: Fluorescence detection, excitation wavelength -295nm, fluorescence wavelength -403nm

  Under the above conditions, the benzpyrene standard product was analyzed, and then the benzpyrene concentration in the bamboo vinegar liquid was tested by directly measuring the commercially available bamboo vinegar liquid sample 1.

  FIG. 4 shows a chromatogram when 50 μL of 1.Oppb (A) and 10ppt (B) benzpyrene standard solutions were injected. As shown in the chromatogram in the figure, a clear benzpyrene peak can be confirmed at the ppb level. In addition, with the high sensitivity fluorescence analysis conditions used this time, good chromatograms were obtained even in the analysis of ultra-dilute 10ppt. At this time, the peak of benzpyrene is a peak around 14.2 minutes, and the peak around 13 minutes is seen in the 1 ppb chromatogram with the same intensity, so it was judged to be a peak derived from other conditions. it can. In this high-sensitivity analysis, it was a ghost peak often seen especially in the case of fluorescence analysis, but it was judged that it would not interfere with the quantitative analysis of benzpyrene, and the bamboo vinegar solution was analyzed.

  Next, the chromatogram in the direct injection of the commercially available bamboo vinegar sample 1 is shown in FIGS. 5 (A) and 5 (B). (A) shows a chromatogram with high peak intensity, but the peaks of other components present in large amounts are very large, and it is impossible to confirm the peak near the benzpyrene elution from the entire chromatogram. is there. Therefore, (B) shows an enlarged chromatogram around the elution time of benzpyrene. As a result, the presence of approximately 10 ppt of benzpyrene in the bamboo vinegar solution 1 was confirmed. The detection limit under the analysis conditions at this time was 1 ppt.

As described above, in the commercially available bamboo vinegar liquid sample 1, the presence of benzpyrene at the ppt level was confirmed. Therefore, in order to explore the possibility of removing benzpyrene next, the possibility of benzpyrene removal using a solid-phase extractant filled with octadecyl group-bonded silica gel (ODS silica), which is widely used as an adsorbent for hydrophobic substances. It was confirmed. The operation method is as follows.
1. Commercial bamboo vinegar sample 1 is filtered through a membrane filter with 0.45μm pores (to remove insoluble components that cannot be visually confirmed)
2. Condition the ODS silica cartridge (Waters, Sep-Pak C18) with methanol and water (to activate the octadecyl group and promote the adsorption of hydrophobic substances)
3. Pass 10mL of filtered commercial bamboo vinegar sample 1 through ODS silica cartridge and collect the passing solution.
4. The treated sample was analyzed by liquid chromatography-fluorescence detection to confirm the presence or absence of benzpyrene. FIG. 6 shows chromatograms before and after purification using an ODS silica cartridge. As shown in FIG. 6, it can be confirmed that in the sample treated with the ODS silica cartridge, the peak of benzpyrene is remarkably reduced. From this chromatogram, it was confirmed that the benzpyrene concentration was removed to about 1 ppt.

  Based on the above, it was judged that solid-phase treatment with ODS silica was effective as a technique for removing trace amounts of benzpyrene in bamboo vinegar. Therefore, benzpyrene concentration measurement including several types of commercial products and evaluation of simple removal methods were continued.

  As described above, the treatment of the ODS silica cartridge showed the possibility of removing benzpyrene in the bamboo vinegar. However, about 1 ppt of benzpyrene remained in the cartridge processing. In order to evaluate the possibility of complete removal with ODS silica, the possibility of complete removal with ODS silica was analyzed by the column switching method.

  The column switching liquid chromatography is constituted by the system shown in FIG. 7, and a certain amount of sample can be introduced into an ODS silica packed column as a pretreatment column. By using this method, it can be known whether complete removal is possible in an ODS silica packed column.

As a result of changing the amount of bamboo vinegar introduced step by step, it was shown that the concentration of benzpyrene could be reduced to 1ppt below the detection limit.
From these results, the possibility of complete removal of benzpyrene with ODS silica was found, and then, as a simple treatment method, further studies using several types of commercially available bamboo vinegar continued .

・ Development of benzpyrene removal method in bamboo vinegar with silica-based adsorbent
1. Measurement of Benzpyrene Concentration in Commercial Bamboo Vinegar Samples Based on the evaluation results in the previous section, the presence of benzpyrene in the bamboo vinegar liquid sampled by the client was confirmed. In addition, the results of cartridge purification and column purification packed with ODS silica showed that benzpyrene could be completely removed by treatment with the same adsorbent. Therefore, in this section, for the purpose of establishing a simple benzpyrene removal technology in commercially available bamboo vinegar, a large amount of bamboo vinegar was treated using an ODS silica adsorbent, and the effect was confirmed.

First, many types of commercially available bamboo vinegar are commercially available. In addition, in the experiment of this section, since a large amount of bamboo vinegar solution treatment is necessary, several kinds of commercially available bamboo vinegar solutions were newly purchased and examined. The used bamboo vinegar is as follows.
Sample of commercial bamboo vinegar sample 2
Commercial bamboo vinegar liquid sample 3
Commercial bamboo vinegar sample 4
Commercial bamboo vinegar solution sample 5 (commercially available as distilled purified product of sample 4)

  In addition, in order to measure the concentration of benzpyrene in these commercially available bamboo vinegar solutions, an attempt was made to measure the concentration of benzpyrene in each bamboo vinegar solution using liquid chromatography-fluorescence detection as in the previous section. The calibration curve used at that time is as shown in FIG. In this calibration curve, good linearity with a correlation coefficient of 0.9999 is obtained when the concentration of benzpyrene ranges from 1 ppt (1 ng / L) to 10 ppb (10 μg / L).

  Benzpyrene concentrations in each bamboo vinegar are summarized in Table 1. Here, a clear peak of benzpyrene could not be confirmed in 2 kinds of bamboo vinegar liquids in 4 kinds of bamboo vinegar liquids. The reason for this is thought to be dependent on the fact that the degree of purification of bamboo vinegar is very low, and therefore there are so many contaminant components other than benzpyrene that it is impossible to detect benzpyrene.

  On the other hand, in the commercially available bamboo vinegar liquid samples 4 and 5, the concentration of benzpyrene was confirmed, which was about 10 ppb for sample 4 and about 60 ppt for sample 5, respectively, suggesting that most of benzpyrene is removed by distillation. However, since the presence of clear benzpyrene was also confirmed in the sample 5 which is a distilled product, the removal method aimed at removing benzpyrene using the above four types of samples was continued.

※竹酢液の精製が不十分であるため、多くの來雑成分が混在すると予想される。前項の一般的な知見から、精製不足の竹酢液にはより高濃度でのベンツピレンの存在が予想される。

* Since the purification of bamboo vinegar is insufficient, many contaminated components are expected to be mixed. From the general knowledge in the previous section, it is expected that benzpyrene is present at a higher concentration in the bamboo vinegar liquid that is not sufficiently refined.

2. Examination of Benzpyrene removal method using 0DS silica
(i) Examination of removal method by batch adsorption method In the previous section, the possibility of removal of benzpyrene in bamboo vinegar by treatment with ODS silica was found. Therefore, in order to examine a simple treatment method using the same adsorbent, we tried to remove benzpyrene by batch adsorption.

The reagents and operation methods used for the evaluation are as follows.
Reagent / Acetonitrile (Wako Pure Chemical Industries)
・ Methanol (Wako Pure Chemical Industries)
・ Pure water (Milli-Q pure water production equipment)
・ ODS silica (Cosmosil 140C ₁₈ -0PN, Nacalai Tesque)
* The average particle size of the ODS silica used in the evaluation is 140 μm.
The ODS surface is hydrophilic. This ODS silica can be used in an open column.

Operation Filter each bamboo vinegar sample using a membrane filter with 0.45μm pores (to remove insoluble components)
↓
Weighed 50 mL of each filtered sample and transferred to a beaker
↓
In each sample, 5 g, 10 g, and 20 g of the ODS silica (dried state) were dispersed.
On this occasion,
In order to confirm the conditioning effect of ODS silica, a comparative sample was separately conditioned with methanol / water for the 10g addition.
↓
The ODS silica dispersion was stirred for 12 hours at room temperature using a stirrer at 200 rpm.

The ODS silica was removed from the sample after stirring by filtration. Furthermore, benzpyrene in the obtained purified solution was quantified.

  FIG. 9 shows a photograph of each bamboo vinegar solution after the ODS silica batch adsorption treatment when the bamboo vinegar sample 3 was used. In the four kinds of bamboo vinegar liquid samples, the coloration of sample 3 is remarkable, and this coloration is considered to depend on the tar content. Therefore, if purification can be confirmed by a visible change, it is expected to be effective in removing benzpyrene.

  As is clear from these photographs, it can be seen that the color of the bamboo vinegar changes dramatically depending on the amount of ODS silica added. Furthermore, as is clear from the comparison between (C) and (E), it was confirmed that the conditioning operation of ODS silica is important for the adsorption effect. As mentioned in the previous section, this is due to the fact that treatment in an organic solvent / water system is important in order to achieve adsorption activation of ODS silica.

  Further, FIG. 10 shows a benzpyrene measurement chromatogram of a sample expected to have the highest purification effect in the batch adsorption treatment of the commercially available bamboo vinegar sample 3. As shown in this chromatogram, the presence of benzpyrene was confirmed in the sample after purification, although only slightly. At this time, the concentration of benzpyrene was about 20 ppt.

  As described above, in the patch treatment of ODS silica, the removal effect of bamboo vinegar liquid tar components, etc. has been confirmed, but the method does not completely remove benzpyrene. Continued.

(ii) Examination of removal method by column method As a result of the above examination, the possibility of removal of benzpyrene in bamboo vinegar was found by adsorption treatment with ODS silica. However, the simple batch adsorption treatment does not have a sufficient removal effect for the intended complete removal, and it is necessary to examine it by another method. Therefore, processing was attempted by column chromatography, which is usually used as a method for processing a large amount of solution.

  A conceptual diagram of the column method used in this evaluation is shown in FIG. In general, a glass tube is filled with an adsorbent (in this case, ODS silica) in the form of a slurry (in a state dispersed in a liquid), and after conditioning, the sample to be measured is passed through. In the process, a component to be removed (benzpyrene in this case) is removed by chemical interaction, and a purified sample can be obtained by collecting the passing liquid. In this test, evaluation was performed using four types of commercially available bamboo vinegar liquid samples. The collected liquid was analyzed by the above-mentioned chromatography method (detection by fluorescence) to confirm the concentration of benzpyrene.

Next, the operation method actually performed is shown below. The reagents used are the same as in the batch adsorption method.

operation
A slurry was prepared by dispersing 20 g of ODS silica in 100 mL of a 30% acetonitrile aqueous solution.
↓
The slurry was filled in a glass column having an inner diameter of 25 mm filled with absorbent cotton and sea sand at one end.
↓
As conditioning, 100 mL each of methanol and water was passed to activate ODS silica.
↓
100 mL of each commercially available bamboo vinegar solution sample was passed through to collect the passing solution.
↓
In order to measure the concentration of benzpyrene in the collected liquid, each collected liquid was analyzed by liquid chromatography-fluorescence detection.

  Here, as a method for regenerating normal ODS silica, cleaning using an organic solvent is considered to be effective. In this evaluation as well, the ODS silica-filled column was washed with alcohol after collecting the flow-through liquid. As a result, the color of the ODS silica was almost removed, suggesting the possibility of reuse.

  Next, sample evaluation results obtained by the column method will be described. First, regarding the evaluation of acidity in the treatment by the column method, no pH change was observed before and after purification in all samples. For example, in the commercially available bamboo vinegar liquid sample 3, the pH before purification was 2.62, whereas it was 2.65 after purification. This result means that the organic acid component containing acetic acid, which is the main component, is not removed before and after purification, suggesting that an organic acid having antibacterial properties remains.

  On the other hand, FIG. 12 shows the state before and after purification of the bamboo vinegar sample 3 shown as a result of the batch adsorption method as a visible change. As is apparent from these photographs, it can be seen that the coloration derived from the tar component is almost completely removed before and after purification. Similarly, it was found that the smell of odor peculiar to bamboo vinegar has almost disappeared. From this, it can be determined that there is a high possibility that tar components and the like containing benzpyrene are efficiently removed.

  Furthermore, the removal effect of benzpyrene was evaluated. As a result, it was revealed that the concentration of benzpyrene was reduced below the detection limit in all the commercially available bamboo vinegar samples. As an example, the final chromatogram of the purified commercial bamboo vinegar sample 5 is shown in FIG. As shown in this figure, the peak of benzpyrene could not be confirmed, and it was possible to remove benzpyrene from the bamboo vinegar by the ODS silica column method.

  As for the reproducibility evaluation, as a result of repeated experiments with the commercially available bamboo vinegar sample 5, no benzpyrene was confirmed in any of the samples, and the reproducibility of this method was good because all of the above four types functioned. It can be judged that there is.

  From the above, it was shown that solid phase treatment with ODS silica, which is one of silica-based adsorbents, is effective as a technique for removing benzpyrene in bamboo vinegar. Furthermore, the effectiveness of the column method was confirmed as a purification method, and it was proved that this method was a good method in terms of the effect of removing benzpyrene and reproducibility.

-Results of analysis of other components As described above, it was confirmed that solid-phase treatment with ODS silica was effective as a method for removing benzpyrene in bamboo vinegar. As for benzpyrene, purification to the original target of 1 ppt or less (below the detection limit) was achieved.

  On the other hand, the substance removed by this operation is not limited to benzpyrene, but may be other tar components, hydrophobic components, and some other polar compounds. From the above visual evaluation results, it was confirmed that the coloration peculiar to bamboo vinegar was removed by the ODS silica treatment. However, also from the above evaluation results, the pH value indicating acidity has hardly changed before and after purification, so that removal of organic acid considered as the main component of antibacterial action in bamboo vinegar has not occurred Can be considered. In order to qualitatively confirm the other components other than these benzpyrenes, the commercial bamboo vinegar solution and the ODS silica-treated sample were analyzed by gas chromatography-mass spectrometry (GC-MS), and the differences in the components were evaluated. . A schematic diagram of the GC-MS system is as follows (FIG. 14). In this method, gas is used as the mobile phase, and detection and qualification according to the mass number of the separation component are efficiently achieved.

The analysis conditions and samples used for the evaluation are as follows. Each component was identified using the commercially available bamboo vinegar liquid sample 2 considered to contain the most components among the evaluated commercial product samples. Moreover, the ODS silica process sample shown below is the same sample as the said column method process, and is a process sample using the commercially available bamboo vinegar sample 5.

Analysis conditions
GC-MS instrument: Agilent 5973
Capillary column with Vent-free GC / MS adaptor: UA5-15M-0.25F (5% polydiphenylsiloxane)
(15m, 0.25mmi.d., 0.25micron)
Sample injection volume
: 1μL
injector
: Split / split less injector-300 ℃, split
ratio: 1/30
GC / MS interface: 300 ℃
MS ion source: 250 ℃

Sample <br/> Commercial bamboo vinegar solution sample 2 (unrefined)
Commercial bamboo vinegar sample 3 (unrefined)
Commercial bamboo vinegar sample 4 (unrefined)
Commercial Bamboo Vinegar Sample 5 (unrefined) (commercially available as distilled product of Sample 4)
ODS silica purified sample (use commercially available bamboo vinegar solution sample 5)

  FIG. 15 shows a GC-MS chromatogram of commercially available bamboo vinegar sample 2. The first half (A) and the second half (B) are shown depending on the elution time. Moreover, the main compound name of each peak obtained from the compound database is as shown. As shown in these chromatograms, it can be seen that a commercially available sample contains an extremely large number of organic acids, phenolic compounds, hydrocarbons, alcohols, ketones and the like. On the other hand, since polycyclic aromatics containing benzpyrene are not detected at all under these conditions, it can be reconfirmed that benzpyrene is extremely dilute compared to the main component.

  As shown in the chromatogram, phenolic compound 2, cresol compound, and other aromatic compounds are present in high concentration in the commercially available bamboo vinegar solution in addition to non-toxic substances such as acetic acid as main components. I understand.

  Although these phenols and cresols have not been reported as carcinogens such as benzpyrene, the acute toxicity value as a chemical substance is about 500 mg / kg for phenol, and 350 mg / kg for cresol, It can be said that there is not much difference from that of Benzpyrene (250mg / kg). Therefore, it is expected that removal of toxic (possible) substance groups in the main component is desirable in simple purification of bamboo vinegar as much as possible.

  Next, regarding the four kinds of commercially available bamboo vinegar liquids including the above-mentioned commercially available bamboo vinegar liquid sample 2, the same analysis was performed and the difference in the contents was evaluated. The GC-MS chromatogram of each commercially available bamboo vinegar solution sample is shown in FIG.

  In the comparison of each chromatogram, the scale of peak signal intensity (vertical axis) proportional to the amount of contained substances is unified, so by comparing each chromatogram, the contained substance concentration in each bamboo vinegar solution Can be seen qualitatively.

  Comparing each, it can be seen that in the commercially available bamboo vinegar sample 2, the most various substances are present in high concentrations. Furthermore, in the comparison between other bamboo vinegar liquor samples, the concentrations of the contained substances are greatly different, and it is suggested that the contents change dramatically due to differences in the bamboo vinegar liquor production method.

  Next, the commercially available bamboo vinegar liquid sample 5 is commercially available as a distilled purified product of the commercially available bamboo vinegar liquid sample 4 as described in the above sample. Therefore, the effect of distillation can be seen by comparing these two chromatograms. As a result, it was found that in the distillate 5, hydrocarbons other than aromatic compounds such as furfural, cresol and syringol were almost removed.

  As described above, qualitative analysis by GC-MS showed the possibility of removing aromatic compounds in bamboo vinegar by distillation purification. On the other hand, from the results of our analysis of benzpyrene, it was clarified that although benzpyrene concentration was greatly reduced by distillation purification, benzpyrene was still present to the extent that it could be detected. Furthermore, as a result of solid-phase treatment with ODS silica as a simple purification method used, we showed that benzpyrene could be reduced below the detection limit.

  Therefore, in addition to the GC-MS untreated sample analysis, the GC-MS analysis was also performed on the sample after the treatment with ODS silica. The processing sample used is a sample obtained by purifying the commercially available bamboo vinegar sample 5 by the same processing as described above.

  The obtained chromatogram is shown in FIG. The figure shows the chromatogram (B) before purification of the commercial bamboo vinegar sample 5 (A) and after treatment with ODS silica. In addition, in the chromatogram (B), a chromatogram in which the vertical axis (detection intensity) is enlarged 10 times is also shown.

  From these results, it can be seen that butylactone, phenolic, guaiacol, syringol and the like contained in the commercially available bamboo vinegar liquid sample 5 are completely removed.

  On the other hand, since the very large peak in the vicinity of 1 minute containing acetic acid as a main component is hardly changed, not only benzpyrene but also aromatic compounds having the same toxicity are removed by the ODS silica treatment. It became clear.

  For confirmation, polycyclic aromatics contained in the purified bamboo vinegar were evaluated using high-sensitivity GC-MS. What was used for evaluation was an unpurified sample of commercially available bamboo vinegar sample 5 and its ODS silica refined product (column method). As a result of detailed analysis, in the unpurified bamboo vinegar sample 5, several tens of ppt of benzpyrene was confirmed as in the fluorescence analysis. On the other hand, in the sample after purification of ODS silica, no major polycyclic aromatics including benzpyrene were detected at all. From these results, benzpyrene removal was proved in other analytical methods, and it was supported that purification by the column method using ODS silica was effective.

  As described above, the presence of benzpyrene, which is a carcinogenic substance, was confirmed by high-sensitivity liquid chromatography-fluorescence detection, although the concentration was very low in the commercially available bamboo vinegar solution.

  In addition, as a method for removing low-concentration benzpyrene in bamboo vinegar, solid-phase treatment methods using ODS silica were evaluated by various methods. As a result, it became clear that the benzpyrene concentration could be reduced below the detection limit by filling the glass column tube with ODS silica and passing the bamboo vinegar sample.

  In addition, the bamboo vinegar sample obtained by the ODS silica treatment almost completely removes the coloring depending on the tar component peculiar to the unpurified product, so the slightly remaining tar component is removed as well. It is thought. On the other hand, from the result of the acidity before and after purification, since there is no significant change, it can be judged that there is almost no removal of organic acids considered to be important for antibacterial action.

  Furthermore, from the qualitative analysis results using gas chromatography, it became clear that the components contained in the commercial products differ greatly, and the effects of distillation purification could also be seen qualitatively. Similarly, in the confirmation analysis of the effect of ODS silica treatment, the removal of some aromatic compounds was confirmed, which supported the effectiveness of ODS silica treatment.

  From these summaries, it can be concluded that the treatment of bamboo vinegar with ODS silica treated in this study is useful as a purification method including removal of extremely low concentration benzpyrene.

Claims (5)

Wood vinegar content of Ru der following 1ppt of benzopyrene carcinogenic substances. A wood vinegar was purified pyroligneous acid before purification, wood vinegar of organic acid component according to claim 1, wherein the remaining not removed after purification containing prior to purification. A method for producing a purified pyroligneous acid solution is characterized in that octadecyl group-bonded silica gel is used as an adsorbent to treat an unpurified pyroligneous acid containing benzpyrene. A method for producing a purified pyroligneous acid solution, comprising filling an open column with a slurry-like octadecyl group-bound silica and then passing the unpurified pyroligneous acid solution through the column. The method for producing a purified wood vinegar solution according to claim 4, wherein the octadecyl group-bonded silica has a hydrophilic surface.

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