【摘要】 丝状真菌发酵体系中菌体形态对产量有着重要影响。考察富马酸产生菌Rhizopus oryzaeME-F12种子培养过程中不同pH条件、孢子悬浮液密度以及CaCl2添加量对其形态的影响。结果表明,当控制种子培养液pH2.3~2.7、接种孢子的终密度为1.5×108~3.0×108/L和添加0.5 g/L CaCl2时,培养可获得直径约为0.65 mm光滑规整菌球,后继的产酸发酵中富马酸量高达58.9 g/L。正交实验表明,pH是影响菌球形成的最主要因素,孢子液密度主要影响菌体生物量,而CaCl2则是菌球表面光滑度的主要影响因素。更多还原

【Abstract】 The effect of pH,inoculum,and CaCl2 in the seed culture medium on the strain morphology and fumaric acid production by Rhizopus oryzae ME-F12 was investigated.When pH was between 2.3 and 2.7,the spore concentration in the flask was 1.5×108 to 3.0×108 spores/L.By adding of CaCl2(0.5 g/L),the strain grew into the uniform and smooth pellet,and the diameter was less than 0.65 mm.In this case,the concentration of fumaric acid was further increased to 58.9 g/L.The orthogonal experiment including factors of pH,inoculum,and CaCl2 was carried out.The result showed that pH was the most significant factor for the morphology,the inoculum affected the mass of seed and CaCl2 affected the surface of pellets.更多还原