摘要
从大量霉菌中选育到一株具有较高富马酸酶活性的温特曲霉(Aspergillus wentii) A5-61。在摇瓶培养条件下,32℃ 96小时,产L-苹果酸达10.49g/100ml,对富马酸的转化率达90.80%。利用菌体细胞,进行酶转化试验,结果表明:1.6g湿菌体接入25ml含富马酸10.0%(用NaOH中和至pH7.0)的转化液中,35℃16~24小时,连续转化三次,分别产生L—苹果酸9.61g/100ml、9.73g/100ml、6.93g/100ml。对菌体整体细胞酶学性质的研究表明,其最适反应温度35℃,最适反应pH7.0,Cu2+对该酶有明显的抑制作用,该酶的Km=0.154mol/L,Vmax=0.0571mol/L·h。
Aspergillus wentii A5-61 with higher fumarase activity was screened from a large number of molds.According to the experimental results. In shake flask culture, L-Malic acid yields was 10.49 g/100ml at 32℃ for 96h, and the conversion rate of fumaric acid was 90.80%. The conversion from fumaric acid to L-malic acid by reusing intact cells showed that intact cells could be used for three times and L-malic acid was produced at yield of 9.61g/100ml, 9.73g/100ml and 6.95g/100ml respectively at 35℃ for 16~24h,when 1.6g wet cells was added to 25ml 10.0% fumaric acid ( neutralized to pH7.0 by NaOH )conversion solution. The study on some properties of intact cells enzyme indicated that the optimum conditions for activity were pH7.0 ,temperature 35℃; the addition of Cu2+ had an obvious inhibiting effect on the enzyme ; Km=0.154mol/L, Vmax=0.0571mol/L·h.
出处
《菌物系统》
CSCD
北大核心
2000年第4期547-551,共5页
Mycosystema
基金
山西省青年科学基金资助项目!(编号931008)
关键词
温特曲霉
L-苹果酸
转化
酶学性质
发酵
Aspergillus wentii, L-malic acid, Conversion, Properties of the enzyme