N^+离子注入热带假丝酵母对长链二元酸产量的影响

MUTATION OF CANDIDA TROPICALIS IMPLANTED BY NITROGEN IONS AND ITS EFFECT IN LONG CHAIN DICARBOXYLIC ACID YIELD

用热带假丝酵母（Ｃａｎｄｉｄａ ｔｒｏｐｉｃａｌｉｓ）ＳＣＢ４１２作为出发菌株，经能量５０ＫｅＶ、剂量１× １０~１１～５ ×１０~１５ ｉｏｎｓ／ｃｍ~２的Ｎ~＋离子注入诱变处理，以产生可遗传的诱变。 Ｎ~＋离子注入后，存活率与剂量呈指数衰减关系：ｌｏｇ（存活率％）＝ ８．２３－ ０．６０４ × ｌｏｇ（剂量），在培养过程中可观察到酵母菌菌落和细胞形态均发生了变化。经筛选，获得了一株能够利用正十二烷烃发酵产生长链二元酸的高产菌热带假丝酵母ＳＣＢ６０９。在初始正十二烷烃浓度为１５％（ｖ／ｖ）下产酸量由４３．５ｇ／Ｌ上升到７３．２ｇ／Ｌ。比较两株菌发酵生长特性的差异，产酸过程有一定的变化。

A mutant Candida tropicalis SCB609, which can produce decane dicarboxylic acid from n-dodecane, was obtained after implanted by Nitrogen ions with energy 50keV and ion fluence from 1 × 10~11 to 5 × 10~15 ions/ cm^2. Fulthermore, the amount of decane dicarboxylic acid was up to 73.29 / L when the fermentation medium contains total 15% n-dodecane. After implanted the logarithm value of survive fraction had good linear relationship with the logarithm value of ion fluence.