阿魏酸酯酶和木聚糖酶协同降解麦糟

Abstract

橘青霉以麦糟为唯一碳源培养时,阿魏酸酯酶的最佳发酵时间为60 H,其酶活力可达40.8 Mu/Ml。在PH值为5.0、45℃、料液比1∶30(g∶Ml)条件下,取47.5 u/Ml的木聚糖酶粗酶液15 Ml,加入1.0 g麦糟的乙醇不溶物,反应12 H后,加入40.8 u/Ml的阿魏酸酯酶粗酶液15 Ml再反应12 H,阿魏酸和低聚木糖释放率分别为54.1%和161 Mg/g(麦糟的乙醇不溶物)。实验结果还表明,阿魏酸酯酶与木聚糖酶存在协同作用,能极大提高麦糟中阿魏酸及低聚木糖的释放率,有利于麦糟的降解。

The optimal fermentation time of Penicillium citrinum feruloyl esterase(PcFAE)was 60 h and its activity was 40.8 mU/mL when the Brewers' Spent Grain(BSG)was used as the sole carbon source for Penicillium citrinum.One gram of alcohol-insoluble residue(AIR)of Brewers'spent grain(BSG)was processed by the solution of crude xylanase(XG180)(47.5 U/mL,15 mL)for 12 hours at the condition of the material-liquid ratio 1∶30(W/V),pH 5.0 and 45 ℃,respectively.And then the solution of crude PcFAE(40.8 mU/mL)was added and the sample was processed for another 12 h.The maximum release rate of Ferulic acid(FA)was 54.1% and the release amount of xylooligosaccharide(XOS)was 161 mg/g(BSG-AIR),respectively.The results of our experiments showed that the release rate of FA and XOS from BSG-AIR increased significantly as the PcFAE could coordinate with the xylanase and enzymolysis process was also conducive to the degradation of BSG.