Effects of carbon sources on fungal morphology and lovastatin biosynthesis by submerged cultivation of Aspergillus terreus

摘要

Various carbon sources resulted in different fungal morphological changes and lovastatin production in submerged cultivation of a mutant of A. terreus. The slowly utilizable carbon source such as glycerol or soluble starch was more beneficial either to lovastatin biosynthesis or to biomass increase. Soluble starch was the most beneficial either for cell growth or for lovastatin biosynthesis due to its best availability on sugar, though glycerol as carbon source produced the highest lovastatin titre. During the period of fermentation, the tardily assimilated carbon sources such as glycerol or soluble starch promoted the fungal morphological differentiation to form regular and compact pellets with slender spongy of outer hyphae and sporangium on the tip of pellet outer hyphae, which were all testified to be beneficial to secondary metabolism. In the presence of slowly metabolized carbon source, the mean filament ratio was linear correlated to the lovastatin production, which reliability could reach to above 0.9.