CN108060190A - A kind of method using edible fungus bran production monose - Google Patents

Abstract

The invention relates to the technical field of utilization and development of edible fungus chaff, and further relates to a method for producing monosaccharides by using edible fungus chaff. The invention overcomes the problems of low hemicellulose content, difficult separation of xylose and glucose and difficulty in industrialized production existing in the prior art. The steps adopted in the present invention are: step 1, acid hydrolysis: edible mushroom chaff, air-dried and pulverized, adding a dilute acid solution with a mass concentration of 1-5% according to a solid-to-liquid ratio of 1:10-20, and treating at 100-120°C for 30- 120min, get the filtrate and filter residue after filtration, and prepare food-grade xylose from xylose in the filtrate; Step 2, alkali hydrolysis: add the alkali solution with a mass concentration of 1-5% to the filter residue according to the solid-liquid ratio of 1:10-20, 40-60 After treating at ℃ for 60-120min, neutralize to neutral with acid, and measure the cellulose content; step 3, enzymatic hydrolysis: add cellulase according to the cellulose content, the amount of cellulose is 10-20FPU/g cellulose, 50℃, Under the condition of 180rpm, enzymolyze for 48-72 hours to obtain the enzymolyzate, and filter to obtain the glucose solution and lignin.

Description

A method for producing monosaccharides from edible fungus chaff

Technical field:

The invention relates to the technical field of utilization and development of edible fungus chaff, and further relates to a method for producing monosaccharides from edible fungus chaff.

technical background:

Edible fungus bran is a solid medium that is discarded after cultivating edible fungi with corncobs, sawdust, cottonseed hulls, rice straw, crop straw or industrial waste (paper mill waste, vinegar grains, distiller's grains, etc.) as the main raw material. At present, the total output of edible fungi in my country has reached 4-5 million tons, with an output value of more than 30 billion yuan. The resulting fungus chaff quantity is also very huge, with an annual output of 7 to 9 million tons. At present, the overall utilization rate of the utilization method of fungus chaff is low, and the added value is not high, which has not only caused a large amount of waste of resources, but also polluted the environment. With the rapid development of the edible fungus industry, how to deal with edible waste mushroom chaff more efficiently has become one of the important issues to be solved urgently in the edible fungus industry.

After the mushroom chaff is grown and utilized by edible fungi, it is still rich in cellulose, hemicellulose and lignin. According to different substrates, the crude fiber content in the fungus chaff accounts for about 10-30%, and the crude protein content accounts for 6-13%. [Edible and Medicinal Fungi, 2015, 23(2): 72‐75]. The research on the utilization of this part of renewable resources is currently mainly focused on fertilizer and feed. For example, microbial fertilizers are directly inoculated with fungus chaff as an adsorption carrier, such as patent 201510748273.9. This method only uses the porosity of the fungus chaff structure as a carrier for adsorption, and its own nutrients are not utilized, and the utilization rate and added value are not good. or carry out a certain composting and fermentation treatment on the chaff, so that the macromolecular substances in the chaff are converted into small molecular substances, and then inoculated with microbial agents to prepare microbial fertilizers, such as patent CN 105777231A. In this method, the chaff is passed through Natural fermentation decomposes, macromolecular substances are degraded and utilized, and the utilization rate is improved, but there are still disadvantages of long natural fermentation period and large floor area. Glucose and xylose produced by the hydrolysis of a large amount of cellulose and hemicellulose in fungal chaff are all available monosaccharides, among which xylose can be further converted into industrial products such as xylitol and furfural; glucose can be used as a carbon source for fermentation For various fermentation products, converting the cellulose and hemicellulose in the fungus chaff into monosaccharides, and then further development and utilization, is an effective conversion method to increase the added value of the fungus chaff. However, since the cellulose and hemicellulose in the natural lignocellulose structure are wrapped inside the lignin, it must be pretreated before it can be used. Patent 200910086798.5 uses alkaline hydrolysis to remove the lignin in the chaff, and then converts cellulose and hemicellulose into glucose and xylose by enzymatic hydrolysis, which improves the overall utilization of the chaff, but the alkali treatment is not effective in removing At the same time as lignin, hemicellulose will be hydrolyzed, causing the loss of hemicellulose. At the same time, the xylose produced by the enzymatic hydrolysis of the remaining hemicellulose and the glucose produced by cellulose hydrolysis are mixed together. The properties of the two monosaccharides are close. It is difficult to separate them by conventional separation techniques. Therefore, reuse is limited, and industrialized production is difficult to realize.

Invention content:

The present invention will provide a kind of method that utilizes edible mushroom chaff to produce monosaccharide, to overcome the low hemicellulose content existing in the prior art, xylose and glucose are difficult to separate, be difficult to carry out the problem of industrialized production.

In order to achieve the purpose of the present invention, the technical solution provided by the present invention is: a kind of method that utilizes edible fungus chaff to produce monosaccharide, comprises the steps:

Step 1. Acid hydrolysis: Edible fungus chaff, air-dried and crushed, add a dilute acid solution with a mass concentration of 1-5% according to the solid-to-liquid ratio of 1:10-20, treat at 100-120°C for 30-120min, and obtain the filtrate and Filter residue, xylose in the filtrate prepares food-grade xylose;

Step 2. Alkali hydrolysis: add the alkali solution with a mass concentration of 1-5% to the filter residue at a solid-to-liquid ratio of 1:10-20, treat at 40-60°C for 60-120 minutes, neutralize with acid to neutral, and measure the cellulose content ;

Step 3, enzymatic hydrolysis: add cellulase according to the cellulose content, the amount of cellulose is 10-20 FPU/g cellulose, enzymatic hydrolysis at 50°C and 180rpm for 48-72 hours to obtain an enzymatic hydrolysis solution, and filter to obtain glucose solution and wood white.

The dilute acid solution in the above step 1 is sulfuric acid or hydrochloric acid, and the xylose in the above-mentioned filtrate prepares food-grade xylose through neutralization, concentration, decolorization, ion exchange and crystallization.

The alkaline solution in the above step 2 is sodium hydroxide or calcium hydroxide solution.

Compared with prior art, the advantage of the present invention is:

1. It can realize the full recycling of fungus chaff and achieve zero discharge: this patent uses acid-base coupling technology to hydrolyze the fungus chaff, and uses a two-step treatment method to hydrolyze the hemicellulose and cellulose in the fungus chaff to produce xylose Collect and utilize glucose step by step. The first step is to select the appropriate dilute acid hydrolysis conditions to maximize the hydrolysis of the hemicellulose in the fungus chaff, avoiding the loss of hemicellulose in the subsequent alkali treatment process, thereby maximizing the yield of xylose; the second The first step is to use dilute alkali to treat the acid hydrolysis raw material, destroy the ester bond and ether bond between the lignin, remove part of the lignin, and improve the enzymatic hydrolysis rate of cellulose. The cellulose raw material after alkali treatment is enzymolyzed by cellulase to form glucose. The solid residue after enzymatic hydrolysis is mainly lignin, which can be used to produce lignin derivatives after modification.

2. The present invention carries out acid-base coupling pretreatment on the fungus chaff, the process conditions adopted are mild, the loss of cellulose and hemicellulose is small, xylose, glucose and lignin can be produced simultaneously, and cellulose, hemicellulose and The graded utilization of lignin improves its added value; makes its reuse simple and feasible, realizes large-scale industrial production, and makes the efficient treatment of edible waste fungus chaff a reality.

3. Small environmental pollution: In the preparation process of the present invention, dilute acid is directly used for neutralization after hydrolysis, which greatly reduces acid discharge and reduces environmental pollution.

Description of drawings:

Fig. 1 is a process flow diagram of the present invention.

Detailed ways:

The invention provides a method for producing monosaccharides by using edible mushroom chaff, specifically a method for obtaining xylose and glucose by hydrolyzing hemicellulose and cellulose step by step through a two-step pretreatment method.

The present invention will be described in detail below through specific examples.

Example 1:

Step 1, acid hydrolysis: air-dry and crush the bran of various edible fungi such as Pingru, Coprinus comatus, and Golden Needle to about 10 mesh. ℃ for 30 minutes, after filtration, the filtrate and liquid residue were obtained;

The content of xylose in the measured filtrate is about 13g/L, and the conversion rate of hemicellulose can reach more than 92%. The filtrate is neutralized, concentrated, decolorized, ion-exchanged and crystallized to prepare food-grade xylose. The xylose output can reach 100g/kg fungus chaff, and further products such as xylitol and furfural can be produced.

Step 2, alkali hydrolysis: add the filter residue to a sodium hydroxide solution with a mass concentration of 5% at a solid-to-liquid ratio of 1:10, treat at 60°C for 60 minutes, neutralize with acid to neutral, and measure the cellulose content;

Step 3, enzymatic hydrolysis: add commercial cellulase ( CTec2, produced by Danish Novozymes Enzyme Preparation Company), the dosage is 20FPU/g cellulose, and the enzymolysis solution is obtained by enzymolysis at 50°C and 180rpm for 48 hours, and the filtrate and filter residue are obtained after the enzymolysis solution is filtered, and the filtrate is glucose solution , its output can reach 40g/L enzymatic hydrolysis solution, which can be used as a carbon source for cultivating various microorganisms after dilution; the main component of the filter residue is lignin, which can be modified to produce various lignin derivatives.

Example 2:

Step 1, acid hydrolysis: air-dry and crush the bran of various edible fungi such as Pingru, Coprinus comatus, and Flammulina to about 10 meshes, and add them to a sulfuric acid solution with a mass concentration of 2% according to a solid-to-liquid ratio of 1:15, 120 ℃ for 60 minutes, after filtration, the filtrate and liquid residue were obtained; the content of xylose in the filtrate was determined to be about 9g/L, and the conversion rate of hemicellulose could reach 90%. The filtrate prepares food-grade xylose through neutralization, concentration, decolorization, ion exchange and crystallization, and the output of xylose can reach 98g/kg bacterium chaff.

Step 2, alkali hydrolysis: add the filter residue to a sodium hydroxide solution with a mass concentration of 2% at a solid-to-liquid ratio of 1:15, treat at 60°C for 100 minutes, neutralize with acid to neutral, and measure the cellulose content;

Step 3, enzymatic hydrolysis: add commercial cellulase ( CTec2, produced by Danish Novozymes Enzyme Preparation Company), the dosage is 10FPU/g cellulose, the enzymolysis solution is obtained by enzymolysis at 50°C and 180rpm for 60 hours, the enzymolysis solution is filtered to obtain filtrate and filter residue, and the filtrate is glucose solution , and its yield has been determined to reach 25g/L enzymatic hydrolyzate.

Example 3:

Step 1, acid hydrolysis: air-dry and crush the bran of various edible fungi such as Pingru, Coprinus comatus, and Golden Needle to about 10 mesh. ℃ treatment for 120min, after filtration, the filtrate and liquid residue were obtained;

The content of xylose in the measured filtrate is about 7g/L, and the conversion rate of hemicellulose can reach 89%. The filtrate is neutralized, concentrated, decolorized, ion-exchanged and crystallized to prepare food-grade xylose, and the yield of xylose can reach 97g/kg fungus chaff.

Step 2, alkali hydrolysis: add the filter residue to a sodium hydroxide solution with a mass concentration of 5% at a solid-to-liquid ratio of 1:20, treat at 60°C for 60 minutes, neutralize with acid to neutral, and measure the cellulose content;

Step 3, enzymatic hydrolysis: add commercial cellulase ( CTec2, produced by Danish Novozymes Enzyme Preparation Company), the dosage is 15FPU/g cellulose, and the enzymolysis solution is obtained by enzymolysis at 50°C and 180rpm for 72 hours, and the filtrate and filter residue are obtained after the enzymolysis solution is filtered, and the filtrate is glucose solution , and its output has been determined to reach 18g/L enzymatic hydrolyzate.

Above-mentioned embodiment 1 is the best embodiment.

Claims (3)

1. A kind of 1. method using edible fungus bran production monose, it is characterised in that：Comprise the following steps：

   Step 1: sour water solution：Edible fungus bran is air-dried and crushed, by solid-to-liquid ratio 1：10~20 add in mass concentration as the dilute of 1-5% Acid solution, 100-120 DEG C of processing 30-120min, obtains filtrate and filter residue after filtering, xylose prepares food-grade xylose in filtrate；

   Step 2: basic hydrolysis：Filter residue presses 1：10~20 solid-to-liquid ratios add in the aqueous slkali that mass concentration is 1-5%, 40-60 DEG C of processing After 60-120min, neutrality is neutralized to acid, measures content of cellulose；

   Step 3: enzyme hydrolysis：By content of cellulose add in cellulase, cellulose dosage be 10-20FPU/g celluloses, 50 DEG C, Enzymolysis liquid is obtained when enzymolysis 48-72 is small under the conditions of 180rpm, filters to obtain glucose solution and lignin.
2. 2. a kind of method using edible fungus bran production monose according to claim 1, it is characterised in that：Above-mentioned steps Dilute acid soln is sulfuric acid or hydrochloric acid in one, in above-mentioned filtrate xylose by neutralizing, it is prepared by concentration, decoloration, ion exchange and crystallization Food-grade xylose.
3. 3. a kind of method using edible fungus bran production monose according to claim 1 or 2, it is characterised in that：It is above-mentioned Step 2 neutral and alkali solution is sodium hydroxide or calcium hydroxide solution.