半纤维素蒸汽爆碎水解物连续发酵生产单细胞蛋白的研究

皮状丝孢酵母(Trichosporon cutaneum)851S是一株能在蒸汽爆碎处理的造纸厂麦秸备料废渣水提液(半纤维素蒸汽爆碎水解物)中生长的较理想单细胞蛋白生产菌株。本文研究了851S在水提液培养基中的连续发酵,其最适稀释率为0.333h~(-1),在此条件下,菌体得率为0.722g/g,菌体生物量为9 22g/l,生产率为3.04g/l,h,比分批培养提高了4.7倍。测定了851S的生长参数:最大比生长速率为0.438h~(-1),最大菌体得率为0.748g/g,碳源维持常数为0.0263gTS/g.b.。 另外,用造纸厂亚铵蒸煮废液抽提汽爆备料废渣制成全废料培养基,以851S作出发菌株,经摇瓶一平板和连续培养两阶段驯化,选育出了一株能在未排毒的亚铵废液抽提培养基上生长的抗性菌株851S-6B-1。连续培养最适稀释率为0.31h~(-1),菌体生物量,菌体得率和生产率分别为8.45g/1,0.692g/g和2.56g/l.h。并测定了851S-6B-1在全废料培养基上的生长参数:最大比生长速率为0.423h~(-1),最大菌体得率为0.704g/g,碳源维持常数为0.027g/g.h.。851S-6B-1具有抗污染、易连续培养、除废渣废液外不需添加任何营养物等优点,具有工业应用前景。

Studies on SCP Production from Hemicellulose Hydrolysate by Continuous Fermentation

Trichosporon cutaneum 851S is a good SCP production strain which is able to grow in water extraction of waste wheat straw (from paper mill) with steam explosion pretreatme-nt. The continuous fermentation of T. cutaneum 85lS in water extract medium was investigated. The best results were obtained at a dilution rate of 0.33 h-1 with yield of 0.722 g of biomass per gram of total suger consumed, 9.22 g of biomass per liter fermentation liquor and a biomass productivity of 3.04 g/l.h. The growth parameters of T. cutaneum 85lS in water extract medium were determined (μmax = 0.438 h-1, YG = 0.748 g biomass/g TS, ms = 0.0263 g TS/ g. biomass. h.).By extracting the steam exploded waste wheat straw with paper mill's spent ammonium sulfite liquor (SASL), an all waste medium was made up. An acclimated strain T. cutaneum 851S-6B-1 which can grow in no inhibitor-eliminating SASL extraction was obtained from T.cutaneum 85lS by means of adaptation in shake flask and continuous cultufermre tank with increasing concentration of SASL. The dilution rate of continuous entation by T.cutaneum 851S-6B-1 in the all-waste medium was 0.31 h- 1 with a yield of 0.692 g/g TS, a biomass of 8.45g/l, a productivity of 2.56 g/l.n.The growth parameters of T.cutaneum 851S-6B-1 in all-waste medium were determined (μmax = 0.423 h-1, YG =0.704 g/gTS, ms = 0.027 g/g.h).