Agricultural & Environmental Biotechnology Group, Department of Biotechnology & Medical Engineering, National Institute of Technology Rourkela, Odisha, India.
Agricultural & Environmental Biotechnology Group, Department of Biotechnology & Medical Engineering, National Institute of Technology Rourkela, Odisha, India.
J Environ Manage. 2020 Apr 15;260:110111. doi: 10.1016/j.jenvman.2020.110111. Epub 2020 Jan 26.
Utilization of waste resources is necessary to harness the long-term sustainability of algal technology. The study focused on the use of human urine as the basic nutrient source for culturing native microalgal consortium and further optimized the process parameters using response surface methodology. A full factorial, central composite rotatable design (CCRD) with three variables: urine concentration (1-10% vol of urine/vol of distil water [%v/v]), pH (6.5-9) and light intensity (50-350 μmolphotonsmsec) was used to evaluate the microalgal biomass and lipid content. Results indicated that at 95% confidence limits, the selected factors influence the biomass and lipid productivity. The maximum biomass productivity of 211.63 ± 1.40 mg l d was obtained under optimized conditions with 6.50% v/v of urine, pH of 7.69 and at light intensity of 205.40 μmolphotonsmsec. The lipid content was found to increase from 18.96 ± 1.30% in control media to 26.27 ± 1.94% under optimal conditions. The interactive effect of variables over the microalgal biomass and lipid content has also been elucidated. The data obtained were comparable to the BG11 media (control). Optimized diluted urine media in the presence of ammonium ions and under limited nitrate showed better lipid yields. Significant lipid biomolecules were detected in the algal oil extracts obtained from the diluted urine media characterized by Fourier transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance (NMR). Gas chromatography-mass spectrometry (GCMS) revealed the presence of several monounsaturated and polyunsaturated fatty acids in the transesterified algal oil. Such studies would aid in technically realizing the field scale cultivation of microalgae for biofuels.
利用废物资源对于实现藻类技术的长期可持续性至关重要。本研究专注于利用人类尿液作为培养本土微藻共生体的基本营养源，并进一步使用响应面法优化了该过程的参数。采用完全析因、中心复合旋转设计（CCRD），以三个变量（尿液浓度[1-10%v/v 尿液/蒸馏水量]、pH 值[6.5-9]和光强[50-350 μmol photons msec]）进行实验，以评估微藻生物量和脂质含量。结果表明，在 95%置信限内，所选因素影响生物量和脂质生产力。在优化条件下，尿液体积分数为 6.50%、pH 值为 7.69、光强为 205.40 μmol photons msec，获得了最大的生物量生产力 211.63 ± 1.40 mg l d。在最佳条件下，脂质含量从对照培养基中的 18.96 ± 1.30%增加到 26.27 ± 1.94%。还阐明了变量对微藻生物量和脂质含量的相互作用效应。获得的数据与 BG11 培养基（对照）相当。在有限的硝酸盐存在下，优化后的稀释尿液培养基中存在铵离子时，可获得更好的脂质产量。从稀释尿液培养基中获得的藻油提取物中检测到显著的脂质生物分子，通过傅里叶变换红外光谱（FTIR）和核磁共振（NMR）进行了表征。气相色谱-质谱联用（GCMS）显示，在转酯化藻油中存在几种单不饱和和多不饱和脂肪酸。这些研究将有助于在技术上实现微藻生物燃料的田间规模培养。
