Academy of State Administration of Grain, Beijing 100037, PR China.
Academy of State Administration of Grain, Beijing 100037, PR China; School of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, PR China.
Food Chem. 2017 May 15;223:49-53. doi: 10.1016/j.foodchem.2016.12.018. Epub 2016 Dec 9.
Rice bran polysaccharides (RBPSs) are valuable compounds with many biological activities. In this work, a fungus called Grifola frondosa, was selected to ferment defatted rice bran water extracts and modify the RBPSs, which were then isolated by ethanol precipitation and deproteinization. GC analysis of fermented products suggested they are composed of glucose, arabinose, galactose, mannose, and xylose at a molar ratio of 9:5:8:2:5, which was 32:4:6:2:5 before fermentation. HPLC analysis revealed that the molecular weight of unfermented RBPS was distributed mainly from 10 to 10Da, and it changed to 10 to 10Da after fermentation. Antioxidant activities and effects on the production of NO were analyzed and it indicated that the scavenging ratios of hydroxyl and DPPH radicals by the fermented products were significantly enhanced compared to the unfermented ones, and also the products fermented for 9days exhibited two-way adjusting effects on the production of NO in macrophages.
米糠多糖（RBPSs）是具有多种生物活性的有价值化合物。在这项工作中，选择了一种名为灰树花的真菌来发酵脱脂米糠水提取物，并对 RBPSs 进行修饰，然后通过乙醇沉淀和脱蛋白进行分离。发酵产物的 GC 分析表明，它们由葡萄糖、阿拉伯糖、半乳糖、甘露糖和木糖组成，摩尔比为 9:5:8:2:5，而发酵前为 32:4:6:2:5。HPLC 分析表明，未发酵的 RBPS 的分子量主要分布在 10 到 10Da 之间，发酵后变为 10 到 10Da。分析了抗氧化活性和对 NO 产生的影响，结果表明，与未发酵产物相比，发酵产物对羟基和 DPPH 自由基的清除率显著提高，而且发酵 9 天的产物对巨噬细胞中 NO 的产生具有双向调节作用。
