4种富锌乳酸菌抗氧化活性及体外消化稳定性研究

Antioxidant activities of 4 types of zinc-rich lactic acid bacteria and their stability in simulated gastrointestinal tract

以4种富锌乳酸菌(保加利亚乳杆菌、嗜酸乳杆菌、发酵乳杆菌、干酪乳杆菌)为研究对象,进行乳酸菌富锌培养的工艺优化,并测定发酵上清液的抗氧化活性,采用体外模拟消化法分析其消化稳定性和生物利用率。结果表明:富锌乳酸菌最佳加锌时间为接种10 h后,锌离子浓度为50μg/mL。富锌培养可提高乳酸菌上清液的抗氧化活性,其中经牡蛎多肽锌培养的乳酸菌上清液自由基(ABTS自由基、DPPH自由基、超氧阴离子自由基)清除活性均高于其他富锌乳酸菌的。由牡蛎多肽锌富锌培养的保加利亚乳杆菌胃肠道释放率为(3.46±0.17)%,且生物利用率最高为(29.78±0.42)%。综上,保加利亚乳杆菌是潜在的优势富锌菌株,经牡蛎多肽锌富锌培养的保加利亚乳杆菌具有良好的体外抗氧化活性、胃肠道消化稳定性和生物利用率。

4 types of lactic acid bacteria(Lactobacillus bulgaricus,L.acidophilus,L.casei,and L.casei)were selected in this study.First,the zinc-rich culture process of lactic acid bacteria was optimized,and then the antioxidant activity of the fermentation supernatant of them was measured,and the digestion stability and bioavailability were further analyzed by in vitro simulated digestion.The results showed that the optimal of zinc addition time for zinc-rich lactic acid bacteria was 10 hours after inoculation,and the zinc ion concentration was 50μg/mL.The antioxidant activity of lactic acid bacteria supernatant could be improved by zinc-rich culture.Four different types of lactic acid bacteria cultured with oyster polypeptide zinc had higher supernatant free radical scavenging activity than that from other zinc sources.The gastrointestinal release rate of L.bulgaricus cultured with oyster peptide-zinc chelates was(3.46±0.17)%,and the bioavailability was the highest(29.78±0.42)%.In summary,L.bulgaricus was a potential dominant zinc-rich strain.L.bulgaricus cultured with the zinc-rich zinc oyster peptide had good in vitro antioxidant activity,gastrointestinal digestive stability,and bioavailability.