Huang Li Ping, Jin Bo, Lant Paul
School of Environmental and Biological Science & Technology, Dalian University of Technology, Dalian, 116023, P. R. China.
Bioprocess Biosyst Eng. 2005 Jul;27(4):229-38. doi: 10.1007/s00449-005-0398-0. Epub 2005 Jun 10.
The biochemical kinetic of direct fermentation for lactic acid production by fungal species of Rhizopus arrhizus 3,6017 and Rhizopus oryzae 2,062 was studied with respect to growth pH, temperature and substrate. The direct fermentation was characterized by starch hydrolysis, accumulation of reducing sugar, and production of lactic acid and fungal biomass. Starch hydrolysis, reducing sugar accumulation, biomass formation and lactic acid production were affected with the variations in pH, temperature, and starch source and concentration. A growth condition with starch concentration approximately 20 g/l at pH 6.0 and 30 degrees C was favourable for both starch saccharification and lactic acid fermentation, resulting in lactic acid yield of 0.87-0.97 g/g starch associated with 1.5-2.0 g/l fungal biomass produced in 36 h fermentation. R. arrhizus 3,6017 had a higher capacity to produce lactic acid, while R. oryzae 2,062 produced more fungal biomass under similar conditions.
研究了少根根霉36017和米根霉2062这两种真菌直接发酵生产乳酸的生化动力学，涉及生长pH值、温度和底物。直接发酵的特点是淀粉水解、还原糖积累、乳酸生成和真菌生物量的产生。淀粉水解、还原糖积累、生物量形成和乳酸生成受pH值、温度、淀粉来源和浓度变化的影响。在pH值为6.0、温度为30℃、淀粉浓度约为20 g/l的生长条件下，有利于淀粉糖化和乳酸发酵，在36小时发酵过程中，乳酸产量为0.87-0.97 g/g淀粉，同时产生1.5-2.0 g/l的真菌生物量。少根根霉36017产生乳酸的能力较高，而米根霉2062在类似条件下产生更多的真菌生物量。
