Department of Marine Biology, Faculty of Marine Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
Department of Marine Biology, Faculty of Marine Sciences, King Abdulaziz University, Jeddah, Saudi Arabia; Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
Chemosphere. 2023 Sep;334:138932. doi: 10.1016/j.chemosphere.2023.138932. Epub 2023 May 18.
Microalgae such as Chlorella pyrenoidosa, Scenedesmus obliquus and Chlorella sorokiniana were cultivated in domestic wastewater for biohydrogen production. The comparison between the microalgae was executed based on biomass productions, biochemical yields and nutrient removal efficiencies. S. obliquus showed the possibility of growing in domestic wastewater reaching maximum biomass production, lipid, protein, carbohydrate yield and nutrient removal efficiency. All the three microalgae reached high biomass production of 0.90, 0.76 and, 0.71 g/L, respectively for S. obliquus, C. sorokiniana and C. pyrenoidosa. A higher protein content (35.76%) was obtained in S. obliquus. A similar pattern of lipid yield (25.34-26.23%) and carbohydrate yield (30.32-33.21%) was recorded in all selected microalgae. Chlorophyll-a content was higher in synthetic media-grown algae compared algae grown in wastewater. The maximum nutrient removal efficiencies achieved were 85.54% of nitrate by C. sorokiniana, 95.43% of nitrite by C. pyrenoidosa, ∼100% of ammonia and 89.34% of phosphorus by C. sorokiniana. An acid pre-treatment was applied to disintegrate the biomass of microalgae, followed by dark fermentation in batch mode to produce hydrogen. During fermentation process, polysaccharides, protein and lipids were consumed. Maximum hydrogen production of 45.50 ± 0.32 mLH/gVS, 38.43 ± 0.42 mLH/gVS and 34.83 ± 1.82 mL/H/gVS was achieved by C. pyrenoidosa, S. obliquus and C. sorokiniana respectively. Overall, the results revealed the potential of microalgal cultivation in wastewater coupled with maximum biomass production lead to biohydrogen generation for environmental sustainability.
小球藻、斜生栅藻和普通念珠藻等微藻被用于从生活废水中生产生物氢气。通过生物量产量、生化产率和营养物质去除效率对微藻进行了比较。斜生栅藻在生活废水中具有最大生物量产量、最高的脂类、蛋白质、碳水化合物产率和营养物质去除效率的生长潜力。三种微藻的生物量产量分别达到了 0.90、0.76 和 0.71g/L，其中斜生栅藻的蛋白含量最高（35.76%）。所有选定的微藻的脂类产率（25.34-26.23%）和碳水化合物产率（30.32-33.21%）相似。与在废水中生长的藻类相比，在合成培养基中生长的藻类的叶绿素-a 含量更高。微藻对营养物质的去除率达到了最大，其中普通念珠藻去除了 85.54%的硝酸盐，小球藻去除了 95.43%的亚硝酸盐，约 100%的氨氮和 89.34%的磷。采用酸预处理来破坏微藻的生物质，然后在分批式黑暗发酵中生产氢气。在发酵过程中，多糖、蛋白质和脂类被消耗。小球藻、斜生栅藻和普通念珠藻的最大氢气产量分别为 45.50±0.32、38.43±0.42 和 34.83±1.82mLH/gVS。总的来说，这些结果表明了微藻在废水处理中的应用潜力，通过最大生物量生产来耦合生物氢气的产生，可以实现环境可持续性。
