不同碳、氮源对球孢白僵菌生长及产孢的影响

摘要

为白僵菌规模化生产和开发利用，以含碳量8 g·L-1的葡萄糖、含氮量0．29 g·L-1的蛋白胨及无机盐为固体基础培养基，用蔗糖等3种碳源（酵母膏等4种氮源）分别等量取代基础培养基中的葡萄糖（蛋白胨），研究了不同碳、氮源对5株球孢白僵菌菌株的菌丝生长和产孢的影响。结果表明，葡萄糖或麦芽糖对菌株B70、B72和B76的生长和产孢明显优于其它碳源，相对于无机氮源，有机氮更利于上述菌株孢子的形成。菌株B76在生物量和产孢上对氮源的利用表现出明显的选择性，硫酸铵显著促进菌丝的生长，而玉米浆更利于孢子形成，其生物量及产孢量分别为645．7 mg ·菌落-1和3．6×109孢子·菌落-1。菌株B246、B252在研究设定的碳氮营养条件下，产孢量明显低于其它菌株，但多糖类可溶性淀粉作为碳源或硝酸钠为氮源显著促进了菌株的生长，菌丝生长旺盛，以硝酸钠为氮源菌株B246、B252生物量最高，分别达1188．6 mg ·菌落-1和1180．5 mg ·菌落-1，表现出对碳氮源利用的特异性。%For the large-scale production of Beauveria bassiana ,development and utilization ,based on defined basal medium composed of glucose(8 .0 g·L-1 carbon) ,peptone(0 .29 g·L-1 nitrogen) ,and etc ,five isolates of the Beauveria bassiana were cultured on solid agar media which glucose or peptone in basal medium were substitu-ted by various carbon sources(sucrose ,maltose ,and soluble starch)or nitrogen sources(yeast extract ,corn steer liquor ,sodium nitrate and ammonium sulphate)at the same of C or N concentrations of basal medium respec-tively .The effect of carbon or nitrogen sources on mycelial growth and sporulation of isolates was evaluated via measurement of biomass and spore yield .The results showed that isolates B70 ,B72 and B76 exhibited com-mendable biomass and spore yield which cultured with glucose or maltose ,and it was significantly better than those cultured with other carbon sources .Compared with the inorganic nitrogen ,organic nitrogen were more suitable for sporulation of B70 ,B72 and B76 .There were obvious selective utilization of nitrogen sources be-tween mycelium growth and sporulation of strain B76 ,the growth of mycelium was evidently promoted by am-monium sulphate in which the biomass was 645 .7 mg · colony-1 ,and corn steer liquor could increase the sporu-lation quantity in which sporulation was 3 .6 × 109 conidia·colony-1 .Under the experimental condition ,the spore yield of strain B246 and B252 were markedly lower than the other isolates’ ,but the biomass of the colony in-creased significantly by polysaccharide soluble starch as C source or inorganic salt sodium nitrate as N source . The highest biomass(1 188 .6 and 1 180 .5 mg·colony-1 )was obtained from the strain B246 and B252 which were cultured with the sodium nitrate as the nitrogen source ,exhibited the specificity of utilization for carbon and nitrogen source .