Isolation and identification of Enterococcus faecium in naturally fermented shrimp sauce and in vitro probiotics properties
Eight strains of acid-producing bacteria were selected from naturally fermented lobster shells,and identified through physi-ological and biochemical tests and 16S rDNA sequence analysis.Based on fermentation characteristics analysis,the highest acid-producing strains LX12-2 and LX18-9 were selected for antibacterial,antioxidant,and in vitro probiotic characteristics analysis and safety evalua-tion.Results showed that there were 7 strains of lactic acid bacteria belonging to the genus Enterococcus,including 5 strains of E.faecalis and 2 strains of Enterococcus faecium.Enterococcus faecalis LX18-9 had the highest acid production ability,broad-spectrum antibacterial activity,and high antioxidant capacity.It had the strongest inhibitory effect on the growth of Listeria monocytogenes,with a diameter of 21.85 mm and a scavenging rate of 76.77％on DPPH free radicals.This strain had a good tolerance to pH 2.0 acid conditions,0.5％bile salt,and artificial gastrointestinal fluid,no histamine production,no hemolysis,and a high safety profile.In summary,the E.faeca-lis LX18-9 screened in this study had high safety and good antibacterial,antioxidant,and probiotic properties,which had potential appli-cation value in feed fermentation production and the development of probiotic products in aquaculture.
crayfishEnterococcus faecalisisolation and identificationprobiotic characteristicssecurity
万方数据
维普
