Method for directionally and rapidly screening lactobacillus plantarum capable of producing bile salt hydrolase

Abstract

The invention discloses a method for directionally and rapidly screening lactobacillus plantarum capable of producing bile salt hydrolase, and belongs to the technical field of microorganisms. The invention comprises the following steps: (1) taking metagenome DNA of a sample as a template, performing PCR amplification on BSHL/BSHR by utilizing a primer, and screening to obtain the sample with a BSH gene; (2) taking the sample as a separating object, and purifying to obtain a suspected plant lactobacillus strain; (3) taking the strain genome DNA as a template, performing PCR amplification on the BSHL/BSHR by utilizing the primer, and screening to obtain a suspected strain with the BSH gene; (4) performing molecular identification on the strain and screening to obtain the lactobacillus plantarum capable of producing bile salt hydrolase. According to the method, most samples which do not contain the lactobacillus plantarum capable of producing the BSH can be filtered out through the firststep of amplification of metagenome-specific fragments, so that blind screening is avoided, the screening range is greatly reduced, and the method has the advantages of directionality, rapidness, easiness, convenience, low workload and the like.

Description

technical field [0001] The invention relates to a method for directional and rapid screening of lactobacillus plantarum producing bile salt hydrolyzing enzyme, which belongs to the technical field of microorganisms. Background technique [0002] In recent decades, cardiovascular disease has become the leading cause of death for all human beings. Clinical trials have shown that high serum cholesterol levels are the main pathogenic factors causing cardiovascular diseases. When the body exceeds the normal value of serum cholesterol level (0-5.2mmo / L), it will show high cholesterol, which will cause the body to suffer from kidney disease, heart disease, stroke and so on. For every 1% increase in cholesterol levels in the body, the risk of cardiovascular disease will increase by 35%. The survey found that in 2012, the number of deaths caused by cardiovascular diseases worldwide (about 17.5 million) accounted for about 31% of the total number of human deaths, of which nearly 42%...

AI Technical Summary

Problems solved by technology

Through comparison, it is found that the operation of method 1) is relatively cumbersome, and it is necessary to test the cholesterol-lowering ability of each bacterial strain isolated and purified, but there will be no omissions. Although the latter two methods are easy to operate, they must be tested first. Separation and purification of lactic acid bacteria, and then screening of lactic acid bacteria with cholesterol-lowering ability by indicator method or calcium precipitation method, the initial isolation workload is relatively large, and the isolated lactic acid bacteria may not have cholesterol-lowering ability, so most of the previous work is useless , and at the same time, the target strain or even the lactic acid bacteria with strong degradation effect may be missed

Therefore, none of the above three methods can be called drow effective

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