Civil Engineering, College of Engineering and Informatics, National University of Ireland, Galway, Ireland.
Water Res. 2013 Jun 15;47(10):3477-83. doi: 10.1016/j.watres.2013.03.046. Epub 2013 Mar 29.
Use of potato processing wastewater for microbial lipid production by oleaginous filamentous fungus Aspergillus oryzae was studied with the purpose of recycling potato processing wastewater for biodiesel production. The wastewater contained high concentrations of solids, starch and nutrients. Sterilization of the potato processing wastewater resulted in a thick gelatinized medium, causing the fungi to grow slow. In order to overcome this problem, the wastewater was diluted with tap water at three dilution ratios (25%, 50% and 75% before fermentation). Dilution of the wastewater not only enhanced lipid production, starch utilization and amylase secretion but also COD and nutrient removal. The dilution ratio of 25% was found to be optimum for lipid production and the maximum lipid concentration obtained was 3.5 g/L. Lipid accumulation was influenced by amylase secretion, and the amylase activity was up to 53.5 IU/mL at 25% dilution. The results show that phosphate limitation may be the mechanism to stimulate the lipid accumulation. In addition to lipid production, removals of COD, total soluble nitrogen and total soluble phosphorus up to 91%, 98% and 97% were achieved, respectively. Microbial lipids of A. oryzae contained major fatty acids such as palmitic acid (11.6%), palmitolic acid (15.6%), stearic acid (19.3%), oleic acid (30.3%), linolenic acid (5.5%) and linoleic acid (6.5%) suggesting that the lipids be suitable for second generation biodiesel production.
利用米糠加工废水生产微生物油脂的研究。以米糠加工废水为原料，生产生物柴油。废水中含有大量的固体、淀粉和营养物质。米糠加工废水的灭菌导致了粘稠的胶化培养基，使真菌生长缓慢。为了克服这个问题，将废水用自来水按三种稀释比（发酵前 25%、50%和 75%）进行稀释。废水的稀释不仅提高了油脂的产量、淀粉的利用率和淀粉酶的分泌，而且还提高了 COD 和养分的去除率。发现稀释率为 25%时最有利于油脂的生产，最大油脂浓度为 3.5g/L。油脂的积累受到淀粉酶分泌的影响，在 25%的稀释率下，淀粉酶活性高达 53.5IU/mL。结果表明，磷酸盐限制可能是刺激油脂积累的机制。除了油脂生产外，COD、总可溶性氮和总可溶性磷的去除率分别达到 91%、98%和 97%。米曲霉微生物油脂含有主要脂肪酸，如棕榈酸（11.6%）、棕榈油酸（15.6%）、硬脂酸（19.3%）、油酸（30.3%）、亚麻酸（5.5%）和亚油酸（6.5%），表明这些油脂适合生产第二代生物柴油。
