栀子蓝色素的制备及其抗氧化活性研究

用米曲霉发酵产物水解栀子苷,水解产物与味精反应制备栀子蓝色素,采用DM-2大孔树脂对产品进行精制,通过DPPH·捕获分光光度法测定栀子蓝色素精制前后的抗氧化活性.栀子蓝制备的最佳条件为:10.64 g栀子苷和129.36 g水混合后,加入米曲霉发酵液9.8 m L,在50℃,160¹80 r/min下水解6 h后,与3.15 g味精反应40 h,80℃保温30 min.所获栀子蓝色素粗品的色价(E1%1cm)为90.56,经DM-2大孔树脂纯化后产品色价提高至180.01%,收率为90.96%.抗氧化实验表明栀子蓝色素粗品和精制品均能有效清除DPPH·,且精制后的栀子蓝色素产品清除DPPH·的能力增强.

Study on the preparation of gardenia blue and its antioxidant activity

Gardenoside is hydrolyzed with fermentation broth of Aspergillus oryzae and reacted with monosodium glutamate,which led to the synthesis of gardenia blue. Gardenia blue is purified by DM- 2 macroporous resin column chromatography. Scavenging DPPH· free radical assay for gardenia blue is carried out. The results have indicated the preferred preparation condition of gardenia blue is that a mixture of 10. 64 g geniposide,129. 36 g H2 O and 9. 8 m L fermentation broth of Aspergillus oryzae is hydrolyzed at 50 ℃ under shaking at 160—180 r / min rotation of 6 h and then reacted with 3. 15 g monosodium glutamate at the same temperature for 40 h and continued to react at 80 ℃ for 30 min. E1%1cm( color value) of the crude reaction product reaches 90. 56. The crude reaction product is chromatographied on the macroporous resin column to get gardenia blue with a production rate of 90. 96% and an E1%1cmof 180. 01. Purified gardenia blue has showed a good DPPH free radical scavenging effect in DPPH free radical assay,which is stronger than that of the crude reaction product.