曲酸产生菌的分离及发酵条件研究(10800字)
摘 要:从腐败的桔皮中分离出一株曲酸产量较高的米曲霉（Aspergillus oryzae）,采用单因素试验法和正交试验法探讨了碳源、氮源、无机盐、发酵温度、初始pH值、接种量、装液量、摇床转速、发酵时间等条件对曲酸产生菌产曲酸的影响。结果表明，适宜的发酵培养基为：玉米淀粉14%、豆饼粉0.5%、K2HPO4 0.1%、MgSO4•7H2O 0.05%、KCl 0.05%、无水乙醇4%；适宜的发酵条件为初始pH 3.5、发酵温度32 ℃、接种量13%（V/V）、装量为60 mL/250 ml三角瓶、摇床转速180 r/min、发酵时间9 d。在此条件下，摇瓶发酵液曲酸含量为20.37 g/L。
关键词：曲酸；米曲霉；发酵；正交试验
Screening of Kojic Acid Producing Strain and Its Fermentation Conditions
Abstract：A high kojic acid producing Aspergillus oryzae was screened from corrupt orange peel. The effects of the fermentation conditions of the kojic acid production such as carbon sources, nitrogen sources, inorganic salt, fermentation temperature, the initial pH value, loading volume, rotatory speed, fermentation time were studied by single-factor test and orthogonal experiment. The results showed that the optimal ferment medium were as follows: corn starch 14%,soybean cake powder 0.5%,K2HPO4 0.1%,MgSO4•7H2O 0.05%,KCl 0.05%,absolute alcohol 4%;the optimal fermentation conditions were: the initial pH value 3.5,fermentation temperature 32 ℃,inoculum 13%(V/V),loading volume 60 mL/250 mL flask. rotatory speed 180 r/min, fermentation time 9 d. Under these conditions, the kojic acid reached 18.13 g/L.
Key words：kojic acid；Aspergillus oryzae；fermentation；orthogonal experiment
 |
