Abstract

Dunaliella salina (D. salina) is a green microalga known for its tendency to produce lipid and β-carotene. Fatty acid profile, lipid and β-carotene productions of the microalga D. salina cultivated under different mixotrophic conditions were assayed. Notably, in spite of a broad spectrum of substrates served, mixotrophic cultivations slightly affected the fatty acid composition, and as a result C16:0 and C18:0, C18:1, C18:2 and C18:3 were identified as main fatty acids. Lipid in dry weight biomass (DWB) hit a high of 24.3% at 5% of NaCL and linolenic acid in lipid reached a peak of 9.15% at 15% of NaCL in medium containing glucose and equal amounts of yeast extract and soy bean powder. One-factor-at-a-time was applied to elucidate the substrates which had noticeable impacts on β-carotene production. Glucose, meat peptone, titanium dioxide nanoparticles (TiO₂ NPs), pH 7.5 and 5% NaCL were identified as key process parameters impacting β-carotene production. Following, the concentration of glucose, meat peptone and TiO₂ NPs were optimized by using response surface method. The highest content of β-carotene, 25.23 mg/g DWB, was obtained in medium composed of (g/L); 22.92 glucose, 5 meat peptone and 0.002 TiO₂ NPs.

摘要

杜氏盐藻( D. salina ) 是一种绿色微藻，以其产生脂质和 β-胡萝卜素的倾向而闻名。微藻D. salina的脂肪酸谱、脂质和 β-胡萝卜素产量测定在不同混合营养条件下培养的。值得注意的是，尽管提供了广泛的底物，但混合营养培养对脂肪酸组成略有影响，因此 C16:0 和 C18:0、C18:1、C18:2 和 C18:3 被确定为主要脂肪酸. 在含有葡萄糖和等量酵母提取物和大豆粉的培养基中，干重生物质 (DWB) 中的脂质在 5% NaCL 时达到 24.3% 的高位，而在 15% NaCL 时脂质中的亚麻酸达到 9.15% 的峰值。一次一个因素用于阐明对β-胡萝卜素产生有显着影响的底物。葡萄糖、肉蛋白胨、二氧化钛纳米粒子（TiO ₂NPs)、pH 7.5 和 5% NaCl 被确定为影响 β-胡萝卜素生产的关键工艺参数。接着，采用响应面法优化葡萄糖、肉蛋白胨和TiO _{2 NPs的浓度。}由(g/L)组成的培养基中β-胡萝卜素含量最高，为25.23 mg/g DWB；22.92葡萄糖、5肉蛋白胨和0.002 TiO ₂ NPs。