风干羊肉中乳酸菌的体内外抗氧化特性

【背景】机体的衰老和一些疾病多与氧化作用有关，随着对抗氧化制剂研究的深入，人工合成抗氧化剂的安全性受到质疑，因此寻找天然抗氧化制剂的研究已成为热点。【目的】从风干羊肉中筛选抗氧化活性较高的乳酸菌，分析肉源乳酸菌体内外抗氧化能力。【方法】以24株肉源乳酸菌为研究对象，以自由基清除能力、亚铁离子螯合能力、还原能力及抗脂质过氧化能力为体外抗氧化能力分析指标，筛选出体外抗氧化活性较强的乳酸菌，运用16S rRNA基因序列同源性分析进行菌种鉴定，通过小鼠试验研究其体内抗氧化能力。【结果】试验所测24株乳酸菌均具有一定的体外抗氧化能力，其中菌株TR13为24株乳酸菌中体外抗氧化能力较强的菌株，其超氧阴离子自由基(·O2?)清除率为54.29%，羟自由基(·OH)清除率为90.84%，1,1-二苯基-2-三硝基苯肼自由基(1,1-diphenyl-2-picrylhydrazyl，DPPH)清除率为99.38%，亚铁离子螯合率为55.85%，还原能力达1.345，抗脂质过氧化率为39.99%。通过16S rRNA基因鉴定，菌株TR13为一株瑞士乳杆菌。通过给D-半乳糖诱导的衰老型小鼠饲喂TR13菌液，验证了TR13对小鼠的肝脏、肾脏及血液组织中谷胱甘肽过氧化物酶(glutathione peroxidase，GSH-Px)活性、超氧化物歧化酶(superoxide dismutase，SOD)活性、过氧化氢酶(catalase，CAT)活性均有显著的提升作用(p<0.05)，且TR13组的GSH-Px活性显著高于维生素C (Vc)组(p<0.05)。【结论】菌株TR13对机体的氧化具有一定的防御作用，研究结果可为乳酸菌抗氧化制剂的研究提供参考依据。

Antioxidation properties in vitro and in vivo of Lactobacillus in air-dried mutton

Background] Aging and some diseases of organism are mostly related to oxidation, with the further research of antioxidant, the safety of synthetic antioxidants is called into question. So the research for natural antioxidants has become a hot topic. Objective] To screen for Lactobacillus with high antioxidant activity from air dried mutton and to analyze their antioxidant capacity in vivo and in vitro. Methods] Taking 24 strains of meat-derived Lactobacillus as research objects, the ability of scavenging free-radical, chelating ferrous ion, reducing and anti-lipid peroxidation were used as the indexes for analyzing the antioxidant capacity in vitro. The 16S rRNA gene sequence homology analysis was used to identify the species, and its antioxidant activity in vivo was studied in mice. Results] All of strains that we tested had anti-oxidation ability in vitro, among them, strain of TR13 had the strongest anti-oxidation ability, its scavenging activity of ·O2? was 54.29%, and scavenging activity of hydroxyl radical was 90.84%, the scavenging activity of DPPH radical was 99.38%, the chelation rate of ferrous ion was 55.85%, the ability to reduce was 1.345, the rate of detecting anti-lipid peroxidation was 39.99%. The strain of TR13 was identified as Lactobacillus helveticus according to the 16S rRNA gene identification. Feeding D-galactose-induced aging mice with TR13 bacterial solution verified that TR13 could promote the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) in liver, kidney, and blood tissues of mice significantly, and the GSH-Px activity of TR13 group was significantly higher than that of vitamin C (Vc) group. Conclusion] The strain of TR13 can effectively prevent oxidative aging for body, and the result can provide reference for researching Lactobacillus antioxidants.