猪骨素发酵及其产物的电泳分析

对红曲霉发酵猪骨素的条件进行了优化,研究了发酵过程中蛋白酶活力和水解度的变化,可溶性氮、肽基氮、游离氨态氮的变化规律以及产物的性质变化。结果表明,红曲发酵猪骨素的适宜工艺为:猪骨素浓度3%,温度30℃,摇床速度120 r/min,自然pH(6.7～7.0);酶活力和水解度在第5天达到最大,分别为35.92 U/mL和38.66%;游离氨态氮含量在发酵过程中逐渐增加,5 d之后趋于稳定,肽基氮含量在第5天时达到最大值为74.21%;可溶性氮含量在生长初期稍有下降,到第5天时其含量达到最大值为88.45%。Tricine-SDS-PAGE电泳结果显示,发酵过程中蛋白分子质量逐渐降低,发酵6 d,发酵液多肽分子质量最小为8.1 ku。

Porcine Bone Extract Fermentation and Electrophoretic Analysis

The optimum conditions for pig bone extract fermented by Monascus were studied in the first part of the paper,as well as the change of protease activity,degree of hydrolysis,soluble nitrogen,peptide-based nitrogen and amino nitrogen in various fermentation period.The results showed that: The optimum conditions were substrate concentration 3%,temperature 30℃,shaking speed 120 r/min,the natural pH(6.7~7.0).The enzyme activity and degree of hydrolysis were up to their max on the 5th day,respectively,35.92 U/mL and 38.66%;Free ammonia nitrogen content increased gradually during the fermentation process,which become stable after 5 days.Peptide-based nitrogen content decreased slightly to a certain value,and finally to a maximum of 74.21% on the 5th day.Soluble nitrogen content in the initial stage of growth declined slightly,also to reach its maximum content of 88.45% on the 5th day.Electrophoretic analysis showed that the protein molecular weight gradually decreased during the six-day fermentation,and the minimum was 8.1kDa after 6 days.