蔗糖糖蜜发酵生产L-苹果酸的研究

Study on L-MalicAcid Production with the Technique of Cane Molasses Fermentation

[目的]研究蔗糖糖蜜预处理、供氧、温度与N源对生产L-苹果酸的影响。[方法]以黄曲霉AF05为出发菌株,蔗糖糖蜜为主要生产原料,通过摇床培养考察糖蜜生产L-苹果酸的发酵条件。[结果]糖蜜预处理能减少糖蜜中有害物质对黄曲霉AF05生长的抑制作用并能促进L-苹果酸的合成,预处理后L-苹果酸含量提高了1倍;当500ml三角瓶装培养液70～100ml及摇床转速200～250r/min时,可获得L-苹果酸合成所需的适合溶氧水平;黄曲霉AF05合成L-苹果酸的最适温度为35℃,另外糖蜜培养基需添加1.0g/L硫酸铵为N源。[结论]糖蜜经预处理后,能稳定合成L-苹果酸。

[Objective] The effect of the pre-treatment,oxygen,temperature and N source in cane molasses on L-malic acid production was studied.[Method] The cane molasses being taken as raw material and Aspergillus flavus AF05,as original strain,the fermentation conditions for L-malic acid production through the shaking culture were evaluated.[Result] The pre-treatment of cane molasses alleviated the inhibition of the harmful substance in cane molasses to the growth of Aspergillus flavus AF05 and promoted L-malic acid formation.The yield of L-malic acid by pre-treated cane molasses was increased by one time as that by un-treated cane molasses.Under the condition of 70-100 ml medium dosage in a 500 ml flask and the rotation speed of 200-250 r/min,an optimum oxygen level for L-malic acid production was got.In addition the optimum temperature of 35 ℃ and（NH4）2SO4 of 1.0 g/L were required for L-malic acid production.[Conclusion] L-malic acid was steadily produced in pre-treated cane molasses medium.