一般認為,溶氧(dissolved oxygen,簡稱 DO)控制真菌代謝物之生產;本研究利用Aspergillus terreus ATCC 20542在五公升醱酵槽中進行不同時機(0-144 h)的DO控制實驗。實驗結果顯示itaconic acid (IA)與lovastatin之產量均以DO 20%(0 h)為最高產量,而兩者亦均以攪拌控制(200 rpm)為最低。且在各不同時機之控制條件下,IA 與lovastatin之產量均呈類比關係,隱含「IA分子可能僅提供lovastatin合成之某種官能基團」之意。此外,本研究也發現此菌絲的增長型態在醱酵槽中會影響代謝物的生產,IA產量主要與「菌株平均粒徑」有關,而lovastatin產量則以「菌絲顆粒密度」為最重要。
It is generally recognized that the level of DO (dissolved oxygen) controls metabolite production by fungi. Using Aspergillus terreus ATCC20542, a control of DO 20% was applied starting from a different timing (0-144 h) of a 5 L fermentation. The results showed that both of the production of itaconic acid (IA) and lovastatin were optimized under DO 20% (0 h), whereas the both were minimized under 200 rpm. The experimental results implied that IA might play a role or act as a group donor in the lovastatin synthesis by the fungus since both seemed to display a proportional production kinetics. Furthermore, the fungal morphology strongly influenced metabolite production. IA synthesis was closely associated with pellet size distribution; meanwhile, lovastatin production was mainly related to pellet density.