Production of L-lactic acid from fresh Cassava roots slurried with tofu liquid waste by Streptococcus bovis
Production of L-lactic acid from fresh Cassava roots slurried with tofu liquid waste by Streptococcus bovis
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DOI：
10.1263/jbb.100.606
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发表时间：
2005-12-01
影响因子：
2.8
通讯作者：
Kokugan, T
中科院分区：
文献类型：
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作者：
Ghofar, A;Ogawa, S;Kokugan, T
为降低生物降解塑料的生产成本，以新鲜木薯根（FCRs）为底物，豆腐渣（TLW）为基本培养基，采用牛链球菌（Streptococcus bovis）分批发酵，研究了其L-乳酸发酵性能。三种底物，即FCR，木薯淀粉（木薯淀粉）和葡萄糖，这是独立地与TLW混合的发酵特性进行了比较，与那些独立地与标准的基础培养基，胰蛋白胨-大豆肉汤（TSB）混合。以CaCO 3为中和剂，在不同糖浓度的底物下进行实验。在TLW中使用三种底物获得的最大L-乳酸浓度（C-La）约为75%。的那些获得使用TSB的TLW中的营养物质较少引起的。L-乳酸生产力（P-La）和比生长速率（P）分别为：TLW组的牛密度（mu）分别为TSB组的1/4 ~ 1/3和1/5 ~ 1/4。最大的C-La，P-La和μ在10%w/w糖浓度下获得。TSB和TLW的总产率（1）在高达10%w/w糖浓度时几乎恒定，即分别为80%至85%和50%至60%。但在两种培养基中，当糖浓度超过10%w/w时，由于底物抑制，它们的总产量下降。发酵性能（C-La，P-La，mu和eta）被发现是在的顺序。FCR >木薯淀粉>葡萄糖，对于所有浓度。三个基板。在TLW和TSB中，FCR和木薯淀粉的发酵性能高于葡萄糖，这是因为S。牛在含有淀粉（FCR和木薯）的培养基中的淀粉酶活性比在含有葡萄糖的培养基中的淀粉酶活性高。在低营养基础培养基（TLW）的FCR中，营养物质对发酵特性的影响比在高营养基础培养基（TSB）的FCR中更大。为了降低生物降解塑料的生产成本，拟采用的TLW浆化FCR发酵培养基值得研究。
To reduce the production cost of biodegradable plastics, the fermentation performance of L-lactic acid for a new fermentation medium, fresh cassava roots (FCRs) as a substrate slurried with tofu liquid waste (TLW) as basal medium, was investigated by batch fermentation of Streptococcus bovis. The fermentation properties of the three substrates, namely, FCR, tapioca (cassava starch) and glucose, which were independently mixed with TLW, were compared with those independently mixed with the standard basal medium, trypto-soya broth (TSB). Experiments were conducted at various sugar concentrations of the substrates with CaCO3 as a neutralizer. The maximum L-lactic acid concentrations (C-La) obtained using the three substrates in TLW were about 75%. of those obtained using TSB caused by less nutrients in the TLW. The L-lactic acid productivities (P-La) and the specific growth rates of S. bovis (mu) in TLW were about 1/4 to 1/3 and 1/5 to 1/4 of those in TSB, respectively. The maximum C-La, P-La and mu were obtained at 10% w/w sugar concentration. Total yields (1) were nearly constant up to 10% w/w sugar concentration for TSB and TLW, that is, 80% to 85% and 50% to 60%, respectively. But their total yields decreased in more than 10% w/w sugar concentration in both basal media, because of substrate inhibition. The fermentation properties (C-La, P-La, mu, and eta) were found to be in the order of. FCR > tapioca > glucose for all concentrations of the. three substrates. The fermentation properties for FCR and tapioca were higher than those for glucose, in TLW or TSB, because S. bovis in a medium containing starch (FCR and tapioca) has more amylase activity than in a medium containing glucose. The nutrients in FCR with poor nutrient basal medium (TLW) more strongly affected the fermentation properties than those in FCR with rich nutrient basal medium (TSB). The proposed fermentation medium of FCR slurried with TLW is worth studying in order to reduce production cost of biodegradable plastics.