角蛋白降解菌Keratinibaculum paraultunense对废弃羽毛的发酵特性研究

Fermentation performances of waste feathers using keratin degrading strain Keratinibaculum paraultunense

采用角蛋白降解菌Keratinibaculum paraultunense厌氧发酵废弃羽毛,以全培养基、无机盐培养基和纯水培养基分别进行发酵,测定了发酵过程中角蛋白酶的酶活、羽毛的降解率、可溶性蛋白和游离氨基酸的含量。研究发现,羽轴比羽枝更难被降解,但羽轴粉碎后,能达到同样的降解效果。采用无机盐培养基发酵时,主要降解产物是可溶性蛋白,含量可达0.93 mg/m L;而采用全培养基发酵时,主要发酵产物是角蛋白酶和游离氨基酸,当羽毛底物量提高到100 g/L,角蛋白酶的酶活高达11 179 U/m L。角蛋白降解菌K.paraultunense能快速高效地降解高浓度的废弃羽毛,可生产大量的可溶性蛋白和高活力的角蛋白酶。

Waste feathers were fermented at anaerobic condition using keratin degrading strain Keratinibaculum paraultunense in the whole medium,inorganic salt medium and pure water medium.The keratinase activity,feather degradation rate,the contents of soluble protein and free amino acids were determined during fermentation process.It was observed that pinna rachis was more difficult to be degraded than that of barbs.However,its degradation rate was comparable with that of barbs when pinna rachis was crushed.The main degradation product was soluble protein in the inorganic salt medium,and the concentration of soluble protein was 0.93 mg/ml.Meanwhile,the main degradation products were keratinase and free amino acids when using whole medium,and the activity of keratinase was 11 179 U/ml when feathers addition was increased to 100 g/L.The results indicated that K.paraultunense can be rapidly and effectively used to degrade high content of waste feathers,producing a large amount of soluble protein and keratinase with high activity.