Abstract

The present study was held to optimize production, purify and identify biosurfactant from yeast strain Geotrichum candidum MK880487. Biosurfactant production was done on modified Hua medium and optimized in shake-flask method. Soybean oil (8%, v/v), KNO₃ (0.75 g L⁻¹) and yeast extract (0.3 g L⁻¹) were the best carbon and nitrogen sources, respectively, with C:N ratio of 200:1, pH 8 at 30 °C for 168 h. Production scale-up was achieved on 2.5 L bioreactor as batch method. The resulting crude biosurfactant extract with yield of 1.75 g L⁻¹ was purified by reversed phase column preparative HPLC. The resulting most active fraction F47 significantly reduced water surface tension by 51.92%. Chemical characterization using TLC, GC-MS, FTIR and LC-MS/MS methods revealed the biosurfactant to contain mainly glycolipid structure existing as mixture of Icariside F2, Cardenolide Di-Hexopyranoside and Di Galactosyl Di Acyl Glycerol glycolipid that collectively showed potential antifungal activity toward Macrophomina phaseolina.

摘要

本研究旨在从酵母菌株白地霉MK880487中优化生产、纯化和鉴定生物表面活性剂。生物表面活性剂的生产在改良的华培养基上进行，并在摇瓶法中进行优化。豆油 (8%, v/v)、KNO ₃ (0.75 g L ^-1 ) 和酵母提取物 (0.3 g L ^-1 ) 分别是最好的碳源和氮源，C:N 比为 200:1， pH 8 在 30 °C 下保持 168 小时。作为批量方法，在 2.5 L 生物反应器上实现了生产放大。所得粗生物表面活性剂提取物的产量为 1.75 g L ^-1通过反相柱制备型 HPLC 纯化。由此产生的最活跃的部分 F47 显着降低了 51.92% 的水表面张力。使用 TLC、GC-MS、FTIR 和 LC-MS/MS 方法进行的化学表征表明，生物表面活性剂主要包含作为 Icariside F2、 Cardenolide Di-Hexopyranoside 和 Di Galactosyl Di Acyl Glycerol 糖脂的混合物存在的糖脂结构，这些糖脂共同显示出潜在的抗真菌活性绿豆螟。