Effects of different bacteria and enzyme fermentation on nutrient content and antimicrobial activity of by-products of authentic Chinese medicinal materials in Guizhou

ZHANG Tao; TANG Yuanjiang; ZHAO Chunping; QI Jing; TAO Xiaoyan; LU Yuxi; ZHOU Sixuan; ZHANG Jing

doi:10.13557/j.cnki.issn1002-2813.2025.04.013

Abstract：To screen the optimal microbial and enzymatic agents for fermenting by-products of authentic Chinese medicinal materials in Guizhou,nine microbial agents and three enzymatic agents were selected to ferment four substrates:Ferment Blumea balsamifera residue(ANX),dangguitiaojing granules residue(DS),relinqing granules residue(THL),and the stems and leaves of Fagopyrum dibotrys Qian Zhong(JQM)for 30 days.The pH value,crude protein,polysaccharide content,and antimicrobial activity of the substrates were comprehensively analyzed to determine the most suitable microbial and enzymatic agents for each herb by-product.The results showed that after fermentation,the pH of all groups was below 5.6.Fermentation with Trichoderma viride reduced crude fiber content and increased crude protein and polysaccharide content in ANX.Fermentation with Aspergillus oryzae reduced crude fiber content and increased crude protein content in DS.Fermentation with Saccharomyces cerevisiae reduced crude fiber content and increased crude protein content in THL,and fermentation with Aspergillus oryzae reduced crude fiber content and increased crude protein and polysaccharide content in JQM.Compared with the control group,the crude fiber content of ANX,DS,THL,and JQM significantly decreased after fermentation with tannase.The inhibition zones of extracts from ANX fermented with different microbial agents against Staphylococcus aureus ranged from 14.30 to 19.83 mm,while those from enzymatic agents ranged from 15.83 to 19.17 mm.For DS,the inhibition zones ranged from 3.50 to 9.83 mm for microbial agents and 4.67 to 7.17 mm for enzymatic agents.For THL,the inhibition zones ranged from 7.17 to 11.67 mm for microbial agents.For JQM,the inhibition zones ranged from 6.83 to 20.83 mm for microbial agents and 13.17 to 17.16 mm for enzymatic agents.The study indicates that the study preliminarily identified Trichoderma viride as the most suitable microbial agent for ANX fermentation,Aspergillus oryzae for DS and JQM fermentation,and Saccharomyces cerevisiae for THL fermentation.Tannase was found to be the optimal enzymatic agent for all the tested medicinal herb by-products.