Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo 255049, China.
Key Laboratory of Meat Processing & Quality Control, College of Food Sciences, Nanjing Agriculture University, Nanjing 210095, China.
Nutrients. 2017 Oct 7;9(10):1101. doi: 10.3390/nu9101101.
Three important strains of grown in complete and minimal media for specified period (72 h, 120 h and 168 h) under submerged fermentation conditions were investigated for their potential antioxidants/secondary metabolite production. All mycelial extracts demonstrated effective antioxidant activities in terms of β-carotene/linoleic acid bleaching, radical scavenging, reduction of metal ions and chelating abilities against ferrous ions. Different extraction methods and solvent systems affected the recovery yield and antioxidant activities of the extracts significantly ( ≤ 0.05). Ethanolic extracts were found to be rich source of antioxidant components and subsequently more effective in antioxidant properties. Fermentation period and media used also significantly affected ( ≤ 0.05) the antioxidant production and the resulting antioxidant properties. The (ethanolic) extracts of all the strains from late exponential growth phase (120 h) showed highest antioxidant production with topmost reducing, chelating and radical scavenging capabilities. Strain MC277.49 was found to be the highest producer of antioxidants followed by MC108.16 and WJ11. Phenolic compounds were detected significantly in higher ( ≤ 0.05) amount succeeded by the condensed tannins and flavonoids. Total phenol content of each extract was attributed to overall antioxidant capacity. Submerged fermentation with nutritional stress conditions were found to be excellent way of producing surplus amount of natural antioxidants/secondary metabolites with their vast potential commercial application in food and pharmaceutical industries.
在深层发酵条件下，将三种在完全和最小培养基中培养规定时间（72 小时、120 小时和 168 小时）的重要生长菌株进行研究，以评估其潜在的抗氧化剂/次生代谢产物的产生。所有菌丝体提取物在β-胡萝卜素/亚油酸漂白、自由基清除、金属离子还原和亚铁离子螯合能力方面均表现出有效的抗氧化活性。不同的提取方法和溶剂系统对提取物的回收产率和抗氧化活性有显著影响（≤0.05）。乙醇提取物是抗氧化成分的丰富来源，因此在抗氧化性能方面更有效。发酵时间和使用的培养基也显著影响（≤0.05）抗氧化产物的产生和由此产生的抗氧化性能。所有菌株的（乙醇）提取物在指数生长期晚期（120 小时）表现出最高的抗氧化产物生成，具有最高的还原、螯合和自由基清除能力。菌株 MC277.49 被发现是最高的抗氧化剂生产者，其次是 MC108.16 和 WJ11。酚类化合物的含量明显更高（≤0.05），其次是缩合单宁和类黄酮。每种提取物的总酚含量归因于其整体抗氧化能力。在营养胁迫条件下进行深层发酵是生产大量天然抗氧化剂/次生代谢产物的绝佳方法，它们在食品和制药行业具有广阔的潜在商业应用前景。
