利用木糖合成β-榄香烯的解脂耶氏酵母构建及其发酵优化OA

β-Elemene is a sesquiterpene natural compound derived from Curcuma aromatica Salisb,a plant belonging to the Zingiber-aceae family.Endowed with excellent antitumor activity,it holds irreplaceable application value in the research and development of antitu-mor drugs as well as their clinical translation.To construct a high-efficiency microbial cell factory for β-elemene synthesis and establish a supporting high-yield fermentation process system,in this study,the engineered Yarrowia lipolytica strain LE-00 was used as the starting strain.A modular metabolic engineering strategy was adopted to perform stepwise rational regulation on the key functional genes involved in the β-elemene biosynthetic pathway,with a systematic analysis of the regulatory mechanism of gene expression patterns on the synthesis ef-ficiency of the target product.First,by strengthening the terpenoid precursor synthesis module,the engineered strain LE-08 was obtained,whose β-elemene yield reached(274.63±4.2)mg/L,representing a 38-fold increase compared with the control strain LE-01.On this basis,the copy number of the key fusion gene ERG20LLTC2 was further increased,which successfully elevated the yield of the target product to(413.28±49)mg/L.To further explore the production potential of the strain,single-factor experiments combined with the Box-Behnken response surface methodology were employed to systematically optimize the components of the fermentation medium.The opti-mal medium formulation was finally determined as follows,xylose 80 g/L,peptone 39.86 g/L,and yeast extract 17.93 g/L.Under these optimized conditions,shake-flask fermentation was carried out in baffled Erlenmeyer flasks,and the β-elemene yield could reach(912.33±70.93)mg/L.In conclusion,this study successfully established a high-efficiency biosynthetic technical route for β-elemene u-sing xylose as the carbon source,which provides important technical support and theoretical basis for reducing the industrial production cost of this compound,improving the economic benefits of the related biopharmaceutical industry,and promoting the industrialization process of natural antitumor drugs.