Detection method of arisaema cum bile fermentation product

Abstract

The invention belongs to the technical field of monitoring analysis, and particularly relates to a detection method of an arisaema cum bile fermentation product. The method comprises the following steps: 1) taking a plurality of groups of equivalent arisaema cum bile fermentation products, adding an organic solvent, respectively carrying out azeotropic treatment, and recovering to obtain a plurality of samples; 2) preparing a standard solution 1 from sulfide, an organic acid solution and a buffer solution, preparing a strong oxidizing solution and a ferrite solution, and preparing a standard solution 2 from anhydride and a solubilizer; and 3) detecting and determining the content of the target component in the sample recovered in the step 1) by using the standard solution 1, the strong oxidizing solution, the ferrite solution and the standard solution 2 through a chemical titration method. The invention provides the detection method for the arisaema cum bile fermentation product, which is convenient and rapid, high in accuracy, high in selectivity and high in reproducibility, and the method is suitable for rapid determination of the arisaema cum bile fermentation product.

Description

Technical Field

[0001] The invention belongs to the technical field of monitoring and analysis, and in particular relates to a method for detecting a fermentation product of Arisaema ciliata. Background Art

[0002] Arisaema heterophyllum Blume is a processed product of Arisaema heterophyllum Blume, which belongs to the woody plant of the genus Araceae, and the tuber contains 28.0wt% starch, which has a high economic value. However, the whole Arisaema has certain toxicity, has a strong stimulation to the mucous membrane in the organism, and has damage to the skin. When the toxin is absorbed by the organism, it will cause nerve paralysis and nerve necrosis. Those skilled in the art reduce the biological toxicity of Arisaema by mixing Arisaema fine powder with animal bile for fermentation processing. After identification by those skilled in the art, it is found that the bound bile acid is converted into free bile acid, such as glycohyocholic acid and taurohyocholic acid are converted into hyocholic acid, glycohyodeoxycholic acid and taurohyocholic acid are converted into hyodeoxycholic acid, glycochenodeoxycholic acid and taurochenodeoxycholic acid are converted into chenodeoxycholic acid, and the fermentation product contains a large amount of heterocyclics, alcohols, aldehydes and aromatics, which are relatively high components. Such ingredients will greatly affect the quality of Arisaema consanguineum, and some of them are even toxic to the human body, so strict characterization and testing of such ingredients are required.

[0003] At present, headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) is commonly used in this field to detect the fermentation products of Arisaema ciliata. However, such methods are cumbersome and costly, while the existing titration characterization methods are difficult to eliminate the influence of interferences, resulting in low detection accuracy.

[0004] Therefore, it is urgent to establish a simple and efficient quality control detection method for Arisaema ciliata. Summary of the invention

[0005] In order to solve the problems that the existing characterization process of Arisaema ciliata fermentation products is relatively cumbersome and difficult to carry out efficiently and concisely, and the current detection methods are generally unable to effectively eliminate the influence of some interferences, resulting in easy deviations in the detection results, the present invention provides a detection method for Arisaema ciliata fermentation products.

[0006] The objects of the present invention are: Provided is a convenient, fast, highly accurate, highly selective and highly reproducible method for detecting the content of Arisaema ciliata fermentation products.

[0007] To achieve the above objectives, the present invention adopts the following technical solutions.

[0008] A method for detecting a fermentation product of Arisaema ciliata. The method comprises: 1) taking multiple groups of equal amounts of Arisaema ciliata fermentation products, adding organic solvents, and performing azeotropic treatment respectively, and recovering multiple samples; 2) Prepare standard solution 1 by taking sulfide, organic acid solution and buffer solution, prepare strong oxidizing solution and ferrous salt solution, and prepare standard solution 2 by taking acid anhydride and solubilizing agent; 3) Using standard solution 1, strong oxidizing solution, ferrous salt solution and standard solution 2, the content of the target component in the sample recovered in step 1) is detected by chemical titration.

[0009] As a preference, Step 1) The dosage of each group of the fermented product of Arisaema ciliata is 3-5 g; In step 1), the organic solvent is sulfolane, and its dosage is 10-20 mL / g of Arisaema ciliata fermentation product.

[0010] As a preference, Step 1) The azeotropic treatment is carried out by maintaining the temperature for 10 to 15 minutes after each heating and condensing and recovering the target liquid phases with different boiling points. The groups include group A, group B and group C. The heating strategies of group A, group B and group C are as follows: The target liquid phase of group A is substance a with a boiling point of 37-38°C; The target liquid phase of group B is substance b with a boiling point of 134-135°C; The target liquid phase of group C is substance c with a boiling point of 201-202°C.

[0011] As a preference, Step 2) the sulfide is 4,4'-bipyridyl disulfide; The organic acid solution is acetic acid, and its dosage is 2-4 mL / g sulfide; The buffer solution is a sodium phosphate solution with a concentration of 0.01-0.02 mol / L and a dosage of 1-2 mL / g sulfide.

[0012] As a preference, Step 2) the strong oxidizing solution is a saturated potassium persulfate solution; Step 2) The ferrous salt solution is a ferrous chloride solution with a concentration of 0.1-0.2 mol / L and a pH value of 3.8-4.2.

[0013] As a preference, Step 2) the acid anhydride is phthalic anhydride; The solubilizing agent is benzene, and its usage is 5-10mL / g of acid anhydride.

[0014] As a preference, The specific method of the chemical titration method in step 3) is as follows: Take substance a in a test tube, add standard solution 1 to substance a, shake the test tube during the addition until the solution turns white or orange, and record the amount of standard solution 1 used; Take substance b and strong oxidizing solution in a volume ratio of (3-4):1, and after reacting for 3-4 hours, add ferrous chloride solution dropwise. During the addition, shake the test tube until yellow appears in the solution, and record the amount of ferrous chloride solution used; Take substance c and standard solution 2 in a volume ratio of 2:(24-26). After the sample is dissolved, place it at 50-70°C for acylation. After reacting for 1-1.5 hours, cool it to room temperature, add phenolphthalein indicator, and drop 0.1 mol / L NaOH solution. Shake the test tube during the addition until a pink color appears in the solution. Record the amount of NaOH solution used.

[0015] As a preference, The amount of the standard solution 1 is used to calculate the dimethyl sulfide content in group A; The content of the ferrous chloride solution is used to calculate the total content of dimethyl sulfide and 2-methylpyrazine; The amount of the NaOH solution used is used to calculate the total content of dimethyl sulfide, 2-methylpyrazine and p-methylphenol.

[0016] In the technical solution of the present invention, a large amount of heterocyclics, alcohols, aldehydes and aromatics in the fermentation product of Arisaema cinerea are evaporated in the gas phase during the azeotropic process. For example, n-octane can be evaporated at 125°C, and 2,3-butanediol can be evaporated at 183°C. In the gas phase enrichment, the low-boiling sulfide dimethyl sulfide will be miscible with alcohols, ethers, esters, ketones, aliphatic and aromatic hydrocarbons and evaporated azeotropically, which will interfere with the detection of the substance content, and it is difficult to simply separate dimethyl sulfide from other components. Therefore, the object of the present invention is to provide a simple and quick detection method.

[0017] According to the research of those skilled in the art, the present invention determines the substances that may be present in the fermentation product. The present invention adds dimethyl sulfide and a small amount of C 2～4The sulfhydryl groups in mercaptan, dithiothioether, etc. are converted into dithiothio groups, and then the dithiothio groups are accurately titrated. By simple calculation, the content of dimethyl sulfide, an interfering substance with a higher content, is first determined. At the same time, pyrazine compounds are soluble in common organic solvents such as alcohol, ether, and water. In order to further eliminate the interference of pyrazine compounds on the results of material content, the present invention is oxidized by potassium persulfate, and organic nitrogen is converted into nitrates, and the amount of dimethyl sulfide and pyrazine compounds is jointly characterized, and the content of pyrazine compounds is determined by simple calculation. The present invention jointly characterizes the content of sulfhydryl-containing compounds, pyrazine compounds, and target substances (p-methylphenol), and the content of p-methylphenol is determined by simple calculation. The technicians, through the determination of precision instruments, found that the difference between the results obtained by the present invention and the results of spectral determination was small, and were suitable for the rapid determination of the fermentation products of Arisaema cava.

[0018] The beneficial effects of the present invention are: The invention provides a method for detecting the content of a fermentation product of Arisaema ciliata, which is convenient, fast, highly accurate, highly selective and highly reproducible. The method is suitable for the rapid determination of the fermentation product of Arisaema ciliata. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with specific embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only embodiments of a part of the present invention, rather than all embodiments. Therefore, based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work should fall within the scope of protection of the present invention.

[0020] Unless otherwise specified, the raw materials used in the examples of the present invention are all commercially available or available to those skilled in the art; unless otherwise specified, the methods used in the examples of the present invention are all methods known to those skilled in the art.

[0021] Example 1 A method for detecting a fermentation product of Arisaema ciliata, the method comprising: 1) Take 3 groups of 5g of the fermented product of Arisaema cinerea, add 50mL of sulfolane, and perform azeotropic treatment. Keep the temperature constant after each heating. 10 to 15 minutes and collect the liquid phase to obtain multiple samples; The specific scheme for heating is as follows: The target liquid phase of group A is substance a with a boiling point of 37-38°C; The target liquid phase of group B is substance b with a boiling point of 134-135°C; The target liquid phase of group C is substance c with a boiling point of 201-202°C; 2) Prepare standard solution 1 by adding 10 g of 4,4'-bipyridyl disulfide, 20 mL of acetic acid, and 10 mL of 0.01 mol / L sodium phosphate solution, prepare saturated potassium persulfate solution and 0.1 mol / L ferrous chloride solution, and prepare standard solution 2 by adding 10 g of phthalic anhydride and 50 mL of benzene; The pH value of the ferrous chloride solution is 4; 3) Take substance a in a test tube, add standard solution 1 to substance a, shake the test tube during the addition until the solution turns white or orange, record the amount of standard solution 1, and calculate the dimethyl sulfide content based on the amount of standard solution 1; 4) Take substance b and the strong oxidizing solution in a volume ratio of 3:1, and after reacting for 3 hours, add ferrous chloride solution dropwise, shake the test tube during the addition process until yellow appears in the solution, record the amount of ferrous chloride solution used, and calculate the total content of dimethyl sulfide and 2-methylpyrazine based on the amount of ferrous chloride solution used; 5) Take 2 g of substance c and 25 mL of standard solution 2, mix them, and after the sample is dissolved, place it at 50°C for acylation. After reacting for 1 hour, cool it to room temperature, add phenolphthalein indicator, and drop 0.1 mol / L NaOH solution. During the dropping process, shake the test tube until a pink color appears in the solution. Record the amount of NaOH solution used, and calculate the total content of dimethyl sulfide, 2-methylpyrazine and p-methylphenol based on the amount of NaOH solution used.

[0022] The sample of the fermentation product of Arisaema ciliata obtained in this example was characterized, and the characterization results are as follows, where the content is the content of the material components contained in each gram of the fermentation product of Arisaema ciliata. Main material components Content (mmol / g) Group A Dimethyl sulfide 0.008 Group B Dimethyl sulfide, 2-methylpyrazine 0.014 Group C Dimethyl sulfide, 2-methylpyrazine, p-methylphenol 1.420

[0023] According to the results in the above table, it can be calculated that the content of p-methylphenol is 1.398mmol / g. In addition, the same cholanthus sibiricum fermentation product is taken for spectral characterization of the p-methylphenol content, and the characterization result is 1.401mmol / g. The characterization result of this embodiment is compared with it, and the visible data deviation value is ≤2.2‰, and the specific content difference is ≤0.003mmol, showing extremely high detection accuracy. The detection method provided by the present invention can more accurately calculate the content of substances contained in the cholanthus sibiricum fermentation product, and this method can meet the requirements of rapid determination of substance content. And, according to further detection, when diluted 2 times, the minimum detection amount of the present invention to the substance is 500ng, indicating that the technical solution has a higher sensitivity and a good prospect in the field of analysis and detection.

[0024] Example 2 The experiment of Example 1 was repeated, and the performance test of Example 1 was carried out on the same sample of the fermented product of Arisaema ciliata. The results are as follows. Main material components Content (mmol / g) Group A Dimethyl sulfide 0.008 Group B Dimethyl sulfide, 2-methylpyrazine 0.014 Group C Dimethyl sulfide, 2-methylpyrazine, p-methylphenol 1.420

[0025] According to the results in the above table, the calculated results are basically the same as those in Example 1, but the actual dosage is slightly different. However, the difference in the results is very small and almost indistinguishable. The results show that the technical solution of the present invention has good reproducibility, and can quickly eliminate the influence of interfering substances such as dimethyl sulfide and 2-methylpyrazine in practical applications.

[0026] Comparative Example 1 A method for detecting a fermentation product of Arisaema ciliata, the method comprising: 1) Take 3 groups of 5g of the fermented product of Arisaema cinerea, add 50mL of sulfolane, and perform azeotropic treatment. Keep the temperature constant after each heating. 10 to 15 minutes and collect the liquid phase to obtain multiple samples; The specific scheme for heating is as follows: The target liquid phase of group A is substance a with a boiling point of 37-38°C; The target liquid phase of group B is substance b with a boiling point of 134-135°C; The target liquid phase of group C is substance c with a boiling point of 215-216°C; 2) Prepare standard solution 1 by adding 10 g of 4,4'-bipyridyl disulfide, 20 mL of acetic acid, and 10 mL of 0.01 mol / L sodium phosphate solution, prepare saturated potassium persulfate solution and 0.1 mol / L ferrous chloride solution, and prepare standard solution 2 by adding 10 g of phthalic anhydride and 50 mL of benzene; The pH value of the ferrous chloride solution is 4; 3) Take substance a in a test tube and add standard solution 1 to substance a. Shake the test tube during the addition until the solution turns white or orange. Record the amount of standard solution 1 used. 4) Mix substance b and the strong oxidizing solution in a volume ratio of 3:1. After reacting for 3 hours, add the ferrous chloride solution dropwise. During the addition, shake the test tube until a yellow color appears in the solution. Record the amount of ferrous chloride solution used. 5) Take 2g of substance c and 25mL of standard solution 2, mix them, and after the sample is dissolved, place it at 50℃ for acylation. After reacting for 1h, cool it to room temperature, add phenolphthalein indicator, and add 0.1mol / L NaOH solution dropwise. During the addition, shake the test tube until a pink color appears in the solution, and record the amount of NaOH solution used.

[0027] The sample of the fermentation product of Arisaema ciliata obtained in this example was characterized, and the characterization method is as follows.

[0028] Take 3 mL of the fermentation product sample of Arisaema ciliata, take the aqueous solution as the control solution, and determine the substance content (mmol / g) in the sample by ultraviolet spectrophotometry.

[0029] The results are as follows. Main material components Content (mmol / g) Group A Dimethyl sulfide 0.008 Group B Dimethyl sulfide, 2-methylpyrazine 0.014 Group C Dimethyl sulfide, 2-methylpyrazine, p-methylphenol, unknown ingredients 1.661

[0030] From the above results, in order to achieve accurate characterization of the target component p-methylphenol, the temperature of each azeotropic process should be relatively strictly controlled. When the azeotropic temperature of group C is increased, it introduces unknown impurities, resulting in a significant increase in the characterization results. The unknown component was spectrally characterized, and the characterization results showed that it was 4-ethylphenol, and the boiling point of 4-ethylphenol was 218-219°C. However, as mentioned above, the components in the fermentation products of Arisaema cinerea are relatively complex, and some components will affect the titration results. For example, 4-ethylphenol is a relatively typical representative. Its continuous azeotropic at a temperature close to the boiling point may cause it to azeotropically evaporate at a temperature that does not reach the boiling point, affecting the actual detection results.

[0031] Comparative Example 2 A method for detecting a fermentation product of Arisaema ciliata, the method comprising: 1) Take 3 groups of 5g of the fermented product of Arisaema cinerea, add 50mL of sulfolane, and perform azeotropic treatment. Keep the temperature constant after each heating. 10 to 15 minutes and collect the liquid phase to obtain multiple samples; The specific scheme for heating is as follows: The target liquid phase of group A is substance a with a boiling point of 45 to 48°C; The target liquid phase of group B is substance b with a boiling point of 134-135°C; The target liquid phase of group C is substance c with a boiling point of 201-202°C; 2) Prepare standard solution 1 by adding 10 g of 4,4'-bipyridyl disulfide, 20 mL of acetic acid, and 10 mL of 0.01 mol / L sodium phosphate solution, prepare saturated potassium persulfate solution and 0.1 mol / L ferrous chloride solution, and prepare standard solution 2 by adding 10 g of phthalic anhydride and 50 mL of benzene; The pH value of the ferrous chloride solution is 4; 3) Take substance a in a test tube and add standard solution 1 to substance a. Shake the test tube during the addition until the solution turns white or orange. Record the amount of standard solution 1 used. 4) Mix substance b and the strong oxidizing solution in a volume ratio of 3:1. After reacting for 3 hours, add the ferrous chloride solution dropwise. During the addition, shake the test tube until a yellow color appears in the solution. Record the amount of ferrous chloride solution used. 5) Take 2g of substance c and 25mL of standard solution 2, mix them, and after the sample is dissolved, place it at 50℃ for acylation. After reacting for 1h, cool it to room temperature, add phenolphthalein indicator, and add 0.1mol / L NaOH solution dropwise. During the addition, shake the test tube until a pink color appears in the solution, and record the amount of NaOH solution used.

[0032] The sample of the fermentation product of Arisaema ciliata obtained in this example was characterized, and the characterization method is as follows.

[0033] Take 3 mL of the fermentation product sample of Arisaema ciliata, take the aqueous solution as the control solution, and determine the substance content (mmol / g) in the sample by ultraviolet spectrophotometry.

[0034] The results are as follows. Main material components Content (mmol / g) Group A Dimethyl sulfide, unknown component 0.010 Group B Dimethyl sulfide, 2-methylpyrazine 0.014 Group C Dimethyl sulfide, 2-methylpyrazine, p-methylphenol 1.420

[0035] From the above results, unknown impurities appeared in Group A, which affected the characterization results of Group A. Although the characterization results of Group A did not affect the results of Group B and Group C and did not affect the characterization results of p-methylphenol, Group A was actually more significant for the scheme of the present invention in terms of the effectiveness of the verification test and the preliminary judgment of the sample quality. If there were significant differences in the characterization results of Group A of different samples of Arisaema cholerae fermentation products, it would indicate poor reliability, or other influences, and Arisaema cholerae fermentation products may introduce other impurity components. On the other hand, 2-methylpyrazine is sometimes used as a characterization item. At this time, the characterization results of Group A can also be effectively used to calculate the content of 2-methylpyrazine, so the azeotropic temperature of Group A also needs to be strictly controlled.

[0036] Comparative Example 3 A method for detecting a fermentation product of Arisaema ciliata, the method comprising: 1) Take 3 groups of 5g of the fermented product of Arisaema cinerea, add 50mL of sulfolane, and perform azeotropic treatment. Keep the temperature constant after each heating. 10 to 15 minutes and collect the liquid phase to obtain multiple samples; The specific scheme for heating is as follows: The target liquid phase of group A is substance a with a boiling point of 37-38°C; The target liquid phase of group B is substance b with a boiling point of 132-133°C; The target liquid phase of group C is substance c with a boiling point of 201-202°C; 2) Prepare standard solution 1 by adding 10 g of 4,4'-bipyridyl disulfide, 20 mL of acetic acid, and 10 mL of 0.01 mol / L sodium phosphate solution, prepare saturated potassium persulfate solution and 0.1 mol / L ferrous chloride solution, and prepare standard solution 2 by adding 10 g of phthalic anhydride and 50 mL of benzene; The pH value of the ferrous chloride solution is 4; 3) Take substance a in a test tube and add standard solution 1 to substance a. Shake the test tube during the addition until the solution turns white or orange. Record the amount of standard solution 1 used. 4) Mix substance b and the strong oxidizing solution in a volume ratio of 3:1. After reacting for 3 hours, add the ferrous chloride solution dropwise. During the addition, shake the test tube until a yellow color appears in the solution. Record the amount of ferrous chloride solution used. 5) Take 2g of substance c and 25mL of standard solution 2, mix them, and after the sample is dissolved, place it at 50℃ for acylation. After reacting for 1h, cool it to room temperature, add phenolphthalein indicator, and add 0.1mol / L NaOH solution dropwise. During the addition, shake the test tube until a pink color appears in the solution, and record the amount of NaOH solution used.

[0037] The sample of the fermentation product of Arisaema ciliata obtained in this example was characterized, and the characterization method is as follows.

[0038] Take 3 mL of the fermentation product sample of Arisaema ciliata, take the aqueous solution as the control solution, and determine the substance content (mmol / g) in the sample by ultraviolet spectrophotometry.

[0039] The results are as follows. Main material components Content (mmol / g) Group A Dimethyl sulfide 0.008 Group B Dimethyl sulfide, 2-methylpyrazine 0.010 Group C Dimethyl sulfide, 2-methylpyrazine, p-methylphenol 1.420

[0040] From the above results, unlike the aforementioned comparative examples 1 and 2, a lower azeotropic temperature was used for group B in this experiment. The actual azeotropic temperature of group B used in the technical solution of the present invention is 134-135°C, which is slightly lower than the boiling point of 2-methylpyrazine, 135°C. However, due to the azeotropic effect, it can be efficiently evaporated. When it is further reduced by 1-2°C, although part of 2-methylpyrazine can be taken out by the azeotropic effect, it is not completely evaporated, resulting in the accuracy of the characterization results being affected. Therefore, it can be seen that for the technical solution of the present invention, in addition to the titration process, the selection and control of the azeotropic temperature will also significantly affect the specific characterization results.

Claims

1. A method for detecting a fermentation product of Arisaema ciliata, characterized in that: The method comprises: 1) taking multiple groups of equal amounts of Arisaema ciliata fermentation products, adding organic solvents, and performing azeotropic treatment respectively, and recovering multiple samples; 2) Prepare standard solution 1 by taking sulfide, organic acid solution and buffer solution, prepare strong oxidizing solution and ferrous salt solution, and prepare standard solution 2 by taking acid anhydride and solubilizing agent; 3) Using standard solution 1, strong oxidizing solution, ferrous salt solution and standard solution 2, the content of the target component in the sample recovered in step 1) is detected by chemical titration.

2. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: Step 1) The dosage of each group of the fermented product of Arisaema ciliata is 3-5 g; In step 1), the organic solvent is sulfolane, and its dosage is 10-20 mL / g of Arisaema ciliata fermentation product.

3. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: Step 1) The azeotropic treatment is carried out by maintaining the temperature for 10 to 15 minutes after each heating and condensing and recovering the target liquid phases with different boiling points. The groups include group A, group B and group C. The heating strategies of group A, group B and group C are as follows: The target liquid phase of group A is substance a with a boiling point of 37-38°C; The target liquid phase of group B is substance b with a boiling point of 134-135°C; The target liquid phase of group C is substance c with a boiling point of 201-202°C.

4. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: Step 2) the sulfide is 4,4'-bipyridyl disulfide; The organic acid solution is acetic acid, and its dosage is 2-4 mL / g sulfide; The buffer solution is a sodium phosphate solution with a concentration of 0.01-0.02 mol / L and a dosage of 1-2 mL / g sulfide.

5. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: Step 2) the strong oxidizing solution is a saturated potassium persulfate solution; Step 2) The ferrous salt solution is a ferrous chloride solution with a concentration of 0.1-0.2 mol / L and a pH value of 3.8-4.

2.

6. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: Step 2) the acid anhydride is phthalic anhydride; The solubilizing agent is benzene, and its usage is 5-10mL / g of acid anhydride.

7. The method for detecting a fermentation product of Arisaema ciliata according to claim 1, characterized in that: The specific method of the chemical titration method in step 3) is as follows: Take substance a in a test tube, add standard solution 1 to substance a, shake the test tube during the addition until the solution turns white or orange, and record the amount of standard solution 1 used; Take substance b and strong oxidizing solution in a volume ratio of (3-4):1, and after reacting for 3-4 hours, add ferrous chloride solution dropwise. During the addition, shake the test tube until yellow appears in the solution, and record the amount of ferrous chloride solution used; Take substance c and standard solution 2 in a volume ratio of 2:(24-26). After the sample is dissolved, place it at 50-70°C for acylation. After reacting for 1-1.5 hours, cool it to room temperature, add phenolphthalein indicator, and drop 0.1 mol / L NaOH solution. Shake the test tube during the addition until a pink color appears in the solution. Record the amount of NaOH solution used.

8. The method for detecting a fermentation product of Arisaema ciliata according to claim 7, characterized in that: The amount of the standard solution 1 is used to calculate the dimethyl sulfide content in group A; The content of the ferrous chloride solution is used to calculate the total content of dimethyl sulfide and 2-methylpyrazine; The amount of the NaOH solution used is used to calculate the total content of dimethyl sulfide, 2-methylpyrazine and p-methylphenol.