Method for preparing intracellular lactase powder by spray drying process of breaking cell walls of lactic acid bacteria

Abstract

The invention relates to a method for preparing an intracellular lactase powder by a spray drying process of breaking cell walls of lactic acid bacteria, comprising the following steps: adjusting operating parameters of a spray dryer such as feed temperature, wind speed and the like, breaking cells of lactic acid bacteria by the utilization of high temperature to release intracellular lactase, and simultaneously adding a protective agent to protect activity of lactase so as to prepare the lactase powder. The protective agent is a mixture of skimmed milk powder and dextrin. Recovery rate of enzyme activity can reach more than 80%. Cell walls are broken by the utilization of high temperature, and usage of chemical reagents such as chloroform and the like is avoided. Thus, environmental pollution stress caused by production process is greatly reduced, and the possibility of polluting an organic reagent in a lactase product is also avoided. Green production of lactase is realized. By merging two processes of crude enzyme preparation and solid enzyme powder preparation, a production technology is greatly simplified, and production efficiency is raised. The method provided by the invention can be suitable for preparation of intracellular enzyme of any cells, including bacteria, fungus, animal cells, plant cells and the like.

Description

technical field

[0001] The invention belongs to the technical field of enzyme preparation, and relates to a method for preparing intracellular lactase powder by crushing the cell wall of lactic acid bacteria by a spray drying method. Background technique

[0002] Lactase, β-galactosidase (EC3.2.1.23), can hydrolyze lactose to generate glucose and galactose. Lactose is the most important carbohydrate in milk and dairy products, but many people cannot digest lactose due to the lack of lactase, and at the same time cause gastrointestinal discomfort, such as diarrhea, intestinal colic, etc., that is, lactose intolerance. About 70% of the Asian population suffers from varying degrees of lactose intolerance. Children with lactose intolerance are prone to calcium malabsorption, rickets, low body weight, and growth retardation; the elderly, especially elderly women, are prone to osteoporosis.

[0003] Utilizing the ability of lactase to hydrolyze lactose can effectively eliminate ...

Examples

Embodiment 1

[0037] Using the chemical method to break the wall to treat the fermentation broth, the steps and instructions are as follows:

[0038] Different cell disruption methods were used to treat the Lactobacillus reuteri fermentation broth, and the lactase activity was determined. The results are shown in Table 1. The efficiency of chemical method to disrupt cells is significantly higher than that of physical method, among which only adding chloroform has the best cell disruption effect, and the enzyme activity is the highest, which can reach 768.7NLU / g. The enzyme activity measured after the cells were disrupted by physical methods was low, indicating that the cells were not fully disrupted and the lactase could not be fully released. Taking the crude enzyme activity after wall breaking with chloroform as 100%, the wall breaking efficiencies of other methods were calculated, and the results are shown in Table 1. The high-pressure cell disruption method had the worst efficiency at 4....

Embodiment 2

[0044] A method for preparing intracellular lactase powder by crushing the cell walls of lactic acid bacteria by a spray drying method, the steps are as follows:

[0045] Add protective agents directly to the fermentation broth, such as dextrin and skimmed milk powder, which can be added separately or mixed. Set the spray dryer operating parameters such as inlet air temperature and material flow rate. The power of different spray drying equipment (laboratory) is different, and the recovery efficiency of enzyme activity is different. For example, SP-1500 experimental spray dryer (Shanghai Shunyi Technology Co., Ltd.), set the air inlet at about 125°C, the material flow rate at about 400mL / h, add skimmed milk powder and dextrin to the fermentation broth at the same time, the ratio is 7: 1. A total of 15% was added, and the recovery rate of enzyme activity was more than 80%.

[0046] In this method, the cells of lactic acid bacteria are swelled and broken by instantaneously inc...

Embodiment 3

[0050] A method for preparing intracellular lactase powder by crushing the cell walls of lactic acid bacteria by a spray drying method, the steps are as follows:

[0051] Add protective agent dextrin directly to the fermentation broth, add 15% dextrin, g / 100mL, set the operating parameters of the spray dryer, the inlet air temperature and material flow rate are 125°C, the material flow rate is 400mL / h, and spray dry to obtain lactase powder .

[0052] Other parts that need to be explained are as follows:

[0053] Fermentation is carried out with the strain MF2-2 as the starting strain, and lactic acid bacteria cells containing lactase are obtained. Further, by breaking the bacterium cell wall through chemical and physical methods in the present invention, a high-activity lactase crude enzyme liquid is obtained, but the crude enzyme liquid is unstable and easily inactivated. The present invention utilizes the spray drying method to directly prepare the lactase preparation, an...

technical field

[0001] The invention belongs to the technical field of enzyme preparation, and relates to a method for preparing intracellular lactase powder by crushing the cell wall of lactic acid bacteria by a spray drying method. Background technique

[0002] Lactase, β-galactosidase (EC3.2.1.23), can hydrolyze lactose to generate glucose and galactose. Lactose is the most important carbohydrate in milk and dairy products, but many people cannot digest lactose due to the lack of lactase, and at the same time cause gastrointestinal discomfort, such as diarrhea, intestinal colic, etc., that is, lactose intolerance. About 70% of the Asian population suffers from varying degrees of lactose intolerance. Children with lactose intolerance are prone to calcium malabsorption, rickets, low body weight, and growth retardation; the elderly, especially elderly women, are prone to osteoporosis.

[0003] Utilizing the ability of lactase to hydrolyze lactose can effectively eliminate ...

Examples

Embodiment 1

[0037] Using the chemical method to break the wall to treat the fermentation broth, the steps and instructions are as follows:

[0038] Different cell disruption methods were used to treat the Lactobacillus reuteri fermentation broth, and the lactase activity was determined. The results are shown in Table 1. The efficiency of chemical method to disrupt cells is significantly higher than that of physical method, among which only adding chloroform has the best cell disruption effect, and the enzyme activity is the highest, which can reach 768.7NLU / g. The enzyme activity measured after the cells were disrupted by physical methods was low, indicating that the cells were not fully disrupted and the lactase could not be fully released. Taking the crude enzyme activity after wall breaking with chloroform as 100%, the wall breaking efficiencies of other methods were calculated, and the results are shown in Table 1. The high-pressure cell disruption method had the worst efficiency at 4....

Embodiment 2

[0044] A method for preparing intracellular lactase powder by crushing the cell walls of lactic acid bacteria by a spray drying method, the steps are as follows:

[0045] Add protective agents directly to the fermentation broth, such as dextrin and skimmed milk powder, which can be added separately or mixed. Set the spray dryer operating parameters such as inlet air temperature and material flow rate. The power of different spray drying equipment (laboratory) is different, and the recovery efficiency of enzyme activity is different. For example, SP-1500 experimental spray dryer (Shanghai Shunyi Technology Co., Ltd.), set the air inlet at about 125°C, the material flow rate at about 400mL / h, add skimmed milk powder and dextrin to the fermentation broth at the same time, the ratio is 7: 1. A total of 15% was added, and the recovery rate of enzyme activity was more than 80%.

[0046] In this method, the cells of lactic acid bacteria are swelled and broken by instantaneously inc...

Embodiment 3

[0050] A method for preparing intracellular lactase powder by crushing the cell walls of lactic acid bacteria by a spray drying method, the steps are as follows:

[0051] Add protective agent dextrin directly to the fermentation broth, add 15% dextrin, g / 100mL, set the operating parameters of the spray dryer, the inlet air temperature and material flow rate are 125°C, the material flow rate is 400mL / h, and spray dry to obtain lactase powder .

[0052] Other parts that need to be explained are as follows:

[0053] Fermentation is carried out with the strain MF2-2 as the starting strain, and lactic acid bacteria cells containing lactase are obtained. Further, by breaking the bacterium cell wall through chemical and physical methods in the present invention, a high-activity lactase crude enzyme liquid is obtained, but the crude enzyme liquid is unstable and easily inactivated. The present invention utilizes the spray drying method to directly prepare the lactase preparation, an...

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