枯草芽孢杆菌发酵复配饲料的抗氧化活性研究

Study on antioxidant activity of compound feed fermented by Bacillus subtilis

试验旨在研究枯草芽孢杆菌发酵复配饲料的抗氧化活性。试验以DPPH法、FRAP法等测定复配发酵饲料自由基清除率和铁离子还原能力,采用福林酚比色法、高效液相色谱法分别测定发酵饲料总酚、大豆异黄酮、山柰素含量,通过主成分分析法对抗氧化指标进行综合评价与分析。结果显示,配比为94%豆粕、4%麦麸、2%银杏叶渣的饲料发酵66 h后抗氧化性能最高;发酵样品提取液的抗氧化能力与抗氧化物质含量均显著提升;铁离子还原力从未发酵时的213.68μmol/L提高至607.68μmol/L;DPPH自由基清除的半最大效应浓度(EC50值)由4.50 g/L减少至2.23 g/L,羟自由基清除的EC50值从3.98 g/L降低至1.51 g/L,超氧阴离子清除的EC50值从2.04 g/L降低至0.76 g/L;样品提取液中大豆苷元、染料木素含量由1.16、0.59 mg/g提高至3.38、1.82 mg/g;染料木苷含量由5.89 mg/g降低至3.83 mg/g;山柰素含量由0提高至3.04 mg/g。总酚含量与超氧阴离子清除率的相关系数最大,为0.827;总黄酮含量与铁离子还原能力相关系数最大,为0.984。超氧阴离子清除率、铁离子还原能力、羟自由基清除率、DPPH自由基清除率与总酚、总黄酮含量之间存在显著的正相关关系。研究表明,枯草芽孢杆菌发酵饲料中总酚、总黄酮、大豆苷元、染料木素等抗氧化成分显著提升,抗氧化能力也随之提高。

The experiment was to study the antioxidant activity of compound feeds fermented by Bacillus subtilis.DPPH method and FRAP method were used to determine the free radical scavenging capacity and iron ion reducing capacity of the compound fermented feed.Folin phenol colorimetry and HPLC were used to determine the content of total phenol,soybean isoflavones and kaempferol in fermented feed.The measured antioxidant indexes were comprehensively evaluated and analyzed by principal component analysis.The results showed that the feed with a ratio of 94% soybean meal,4% wheat bran and 2% Ginkgo biloba residue had the highest antioxidant performance after 66 h of fermentation.The antioxidant capacity and the content of antioxidant substances of fermentation sample extract have been significantly improved.The reducing power of iron ions increased from 213.68 μmol/L to 607.68 μmol/L.The EC50 value of DPPH free radical clearance was reduced from 4.50 g/L to 2.23 g/L,and the hydroxyl free radical clearance was reduced from 3.98 g/L to 1.51 g/L,the superoxide anion clearance was reduced from 2.04 g/L to 0.76 g/L.Through fermentation,the content of daidzein and genistein in sample extract increased from 1.16,0.59 mg/g to 3.38,1.82 mg/g.The content of genistein was reduced from 5.89 mg/g to 3.83 mg/g.The content of kaempferol was increased from 0 to 3.04 mg/g.The correlation coefficient between total phenol content and superoxide anion clarification ability was the largest,which was 0.827,the correlation coefficient between total flavonoid content and iron ion reduction ability was the largest,which was 0.984.There was a significant positive correlation between superoxide anion scavenging ability,iron ion reduction ability,hydroxyl radical scavenging ability,DPPH free radical scavenging ability and total phenol,total flavonoid content.The study indicates that the antioxidant components such as total phenol,total flavone,daidzein and genistein in Bacillus subtilis fermented feed are significantly increased,and the antioxidant capacity is also increased.