红曲霉产琥珀酸与酯化酶的变化规律

Changes in the Production of Succinic Acid and Esterifying Enzymes during the Growth of Monascus purpureus

分别对红曲霉生长过程中产生的琥珀酸和酯化酶进行色谱分析和酶活力测定,探讨红曲霉产琥珀酸与酯化酶的变化规律。研究在不同时间、不同培养条件及菌体状态下,红曲霉产琥珀酸及酯化酶的动态变化情况,以获得红曲霉产琥珀酸和酯化酶的最佳培养时间和最佳培养状态。结果表明:琥珀酸在红曲霉生长的第5天即达到最大值3.62 g/L,随后琥珀酸质量浓度明显下降;酯化酶在红曲霉生长过程中可不断地积累,在第9天酯化酶酶活力达到143.65 U/mL;接种量、pH值、温度、转速及菌体形状等影响琥珀酸及酯化酶的产量;颗粒状菌体发酵有利于琥珀酸及酯化酶的积累;接种量为10%、初始pH 6.5、30℃、180 r/min条件下培养至第6天,可兼顾琥珀酸及酯化酶的积累。

The amount of succinic acid and esterifying enzyme activities produced during the growth of Monascus purpureuswere measured by chromatographic analysis and enzyme activity assay to monitor the dynamic changes in the production of succinic acid and esterifying enzymes. The culture conditions were optimized for enhanced production of succinic acid and esterifying enzymes by this strain. The results showed that the production of succinic acid reached a peak of 3.62 g/L on the fifth day, and decreased obviously after the sixth day; while esterifying enzyme activities continued to accumulate until reaching 143.65 U/mL on the ninth day. All inoculum size, pH, temperature, shaking speed and fungal morphology could affect the production of succinic acid and esterifying enzymes. Granular fungi produced more succinic acid and esterifying enzymes. Considering both parameters, the fermentation should be terminated on the sixth day under the optimized culture conditions of 10%, 6.5, 30 ℃ and 180 r/min for inoculum size, initial pH, temperature and shaking speed, respectively.