乳酸菌发酵对糯性黑色元麦生化成分及体外抗氧化能力的影响

摘要

为研究乳酸菌发酵对糯性黑色元麦生化成分及体外抗氧化能力的影响,分别采用平板计数法、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳技术 (SDS-PAGE) 及ORAC法 (Oxygen radical absorbance capacity) 对乳酸菌生长情况、元麦蛋白质水解情况及体外总抗氧化能力进行测定.结果表明:发酵36 h后,元麦pH值下降至 3.84±0.04,乳酸菌活菌数显著增加,达到 3.49×109CFU/g;元麦蛋白质明显水解,可溶性蛋白质含量显著减少,大分子蛋白质降解率为 9.56%~31.10%,小分子蛋白质的最大生成率达22.26%.总酚含量显著增加,由 (4.87±0.10) mg/g增至 (5.61±0.02) mg/g;植酸含量显著减少,由(3.16±0.03) mg/g降低至 (2.17±0.11) mg/g.DPPH自由基清除能力和铁离子还原能力均显著提高,总抗氧化能力由 (386.39±21.13) μmol /ml增加至 (463.92±23.61) μmol /ml.%In this paper, the response of biochemical components and in vitro antioxidant capacities of waxy black hulless barley to lactobacillus fermentation was studied.Lactic acid bacteria growth, the proteolysis of barley and total antioxidant capacities were investigated by plate count method, sodium dodecyl sulfate polyacrylamide-gel electrophoresis (SDS-PAGE) and oxygen radical absorbance capacity (ORAC), respectively.Results showed that, 36 h after the fermentation, pH value decreased rapidly to 3.84±0.04, and the viable counting number of lactobacillus increased to 3.49×109CFU/g.Owing to the remarkable proteolysis of barley, soluble protein content was reduced by a large margin.High-molecular-weight barley protein were significantly hydrolyzed by 9.56%-31.10% and the maximum degradation rate of low-molecular-weight protein was 22.26%.Total phenolic content was also determined, with a value increased from (4.87±0.10) mg/g to (5.61±0.02) mg/g.Phytic acid content was reduced from (3.16±0.03) mg/g to (2.17±0.11) mg/g, due to enzymatic hydrolysis.Moreover, fermented barley showed higher DPPH free radical scavenging activity and ferric reducing antioxidant power, and its total antioxidant capacity was increased from (386.39±21.13) μmol /ml to (463.92±23.61) μmol /ml.