发酵法生产衣康酸技术的研究——衣康酸发酵工艺条件的研究(Ⅱ)

Studies on Itaconic Acid Production by Fermentation Process —Studies on the Technical Conditions of Itaconic Acid Production(Ⅱ)

以衣康酸高产菌株土曲霉HAT418为出发菌株 ,研究探讨了不同碳源、氮源、无机盐类以及温度、起始 pH值等因素对衣康酸发酵的影响 ,确定了较优培养基组成和发酵工艺条件。实验结果表明 ,土曲霉HAT418适合于多种原料的衣康酸生产 ,如玉米淀粉、山芋粉、低脂玉米粉、蔗糖、口服葡萄糖等 ;硝酸铵、硫酸铵是衣康酸发酵的最适氮源 ,玉米浆是必要的辅助氮源 ;适宜的发酵起始pH值在 2 5～ 3 0 ;适宜的发酵温度为 3 6～ 3 7℃ ;Mg2 + 对土曲霉HAT418菌株的衣康酸发酵影响显著 ,适量的Mg2 + 是衣康酸发酵必需的 ;Ca2 + 可抑制杂酸的形成 ,培养基中添加 0 1g/L的CaCl2 可以使发酵液中衣康酸占总酸的比例提高 1 2 3 %。土曲霉HAT418菌株以 12 0～ 160 g/L的玉米淀粉双酶水解糖为碳源 ,NH4NO3 为主要氮源 ,摇瓶发酵 80h左右 ,衣康酸产酸率达到 83 0～10 1 1g/L ,糖酸转化率为 63 13 %～ 69 17% ,发酵残糖为 0 9～ 9 7g/L。

The effects of fermentation conditions on the production of itaconic acid by Aspergillus terreus HAT418 were studied. The results indicated it could improve the production of itaconic acid when corn starch,glucose or sucrose acted as carbon source, (NH 4) 2SO 4 or NH 4NO 3 as nitrogen source and corn steep liquor as auxiliary nitrogen source. The optimal start pH value and temperature optimum are 2 5～3 0 and 36～37℃respectively. It was also found that the addition of C [Mg 2+ ] could promote the growth of mycelia and itaconic acid production and Ca 2+ could increase the proportion of itaconic acid to total acid in fermented liquor. Under the optimal cultural conditions, the Aspergillus terreus HAT418 could accumulate 83.0～101.1?g/L itaconic acid from 120～160?g/L sugar. The conversion ratio of sugar to acids and the remains of reducing sugar reached 63 13%～69 17% and 0 9～9 7?g/L respectively