Efficient production of mannosylerythritol lipids by a marine yeast Moesziomyces aphidis XM01 and their application as self‑assembly nanomicelles

Mannosylerythritol lipids(MELs)are one of the most promising biosurfactants because of their excellent physicochemical properties,high environmental compatibility,and various biological functions.In this study,a mangrove yeast strain Moesziomyces aphidis XM01 was identified and used for efficient extracellular MEL production.The MEL titer reached 64.5±0.7 g/L at flask level within 7 days with the optimized nitrogen and carbon source of 2.0 g/L NaNO_(3) and 70 g/L soybean oil.Furthermore,during a 10-L two-stage fed-batch fermentation,the final MEL titer reached 113.6±3.1 g/L within 8 days,with prominent productivity and yield of 14.2 g·L^(−1)·day^(−1)and 94.6 g/g_((glucose and soybean oil)).Structural analysis indicated that the produced MELs were mainly MEL-A and its fatty acid profile was composed of only medium-chain fatty acids(C8–C12),especially C10 acids(77.81%).Further applications of this compound were evaluated as one-step selfassembly nanomicelles.The obtained MEL nanomicelles showed good physicochemical stability and antibacterial activity.In addition,using clarithromycin as a model hydrophobic drug,the MEL nanomicelles exhibited high loading capacity and could be used for the controlled and sustained drug release in low-pH environments.Therefore,M.aphidis XM01 is an excellent candidate for efficient MEL production,and the prepared MEL nanomicelles have broad application prospects in the pharmaceutical and cosmetic fields.