To explore the influencing factors of fermentation and bioactivity of Aureobasidium pullulan LHS-m022 melanin-polysaccharide, using strain fermentation, isolation and extraction, and biological detection methods, the properties of the fermentation broth, product yield, bioconversion rate and bioactivity were determined and analyzed. The results showed that the best carbon and nitrogen sources of LHS-m022 melanin-polysaccharide fermentation were sucrose and casein peptone, and the optimal concentration of sucrose was 60 g/L. The optimal amount of inducer L-dopa in the fermentation medium was 2.0 g/L, and the blackening activity and bioconversion rate of the fermentation broth were 2.481 and 71.93%, respectively. The optimal amount of cell permeating agent rhamnolipid was 0.021 μL/L, and the blackening activity and bioconversion rate of fermentation broth were as high as 2.794 and 73.9%, respectively. Full wavelength scan, FTIR and HPLC analysis showed that WAI was melanin, and PsB was melanin-glucan structure. The research revealed that the crude melanin-glucan samples treated above 121℃ still gave 95.37% FR. Testing with the respective sample concentrations of 1.50 g/L and 2.00 g/L yielded the corresponding 99.55% hydroxyl radical scavenging activity and 99.00% antioxidant activity.

Aureobasidium pullulan LHS-m022, melanin-glucan, blackening activity, bioconversion rate, antioxidant activity, hydroxyl radical scavenging activity

为探索出芽短梗霉LHS-m022黑色素多糖的发酵影响因素和生物活性, 采用菌种发酵、分离提取及生物检测方法, 对发酵液性质、产物收率、生物转化率及生物活性进行测定分析。结果表明, LHS-m022黑色素多糖发酵的最佳碳、氮源分别是蔗糖和胰酪蛋白胨, 蔗糖最佳浓度为60 g/L; 发酵培养基中诱导剂L-多巴的最适添加量为2.0 g/L, 发酵液黑变活性和生物转化率分别是2.481和 71.93%; 细胞通透剂鼠李糖脂的最适添加量是0.021 μL/L, 发酵液黑变活性和生物转化率分别高达2.794和73.9%。全波长扫描、FTIR与HPLC分析表明, WAI为黑色素, PsB为黑色素葡聚糖结构。研究结果揭示, 粗黑色素葡聚糖样品经121℃以上高温处理, 仍然得到95.37%的絮凝率。采用1.50和2.00 g/L的样品浓度进行检测, 分别得到99.55%的羟自由基清除活性和99.00%的抗氧化活性。

出芽短梗霉LHS-m022, 黑色素葡聚糖, 黑变活性, 生物转化率, 抗氧化活性, 羟自由基清除活性