Cultivating photosynthetic microbes in city wastewater may help to achieve environmental sustainability owing to concomitant pollutant removal, biological transformation of the nutrients into bioproducts, and atmospheric carbon fixation. Cyanobacteria are the most efficient photosynthetic fixers of atmospheric carbon along with the microalgae. The present study was focused on optimizing the growth conditions for a newly isolated filamentous cyanobacterium Plectonema terebrans BERC10 to achieve enhanced biomass and metabolite productivity for a multiproduct biorefinery using various compositions of synthetic wastewaters. Higher biomass productivity of 140 mg L⁻¹ d⁻¹ (dried mass) with CO₂ sequestration rate of 250 mg L⁻¹ day⁻¹ was achieved by mimicking the summer (32 ± 2 °C) cultivation conditions, which was further favored by the wastewater-derived alkalinity (pH 10.0–11.0). The biomass produced was rich in carbohydrates and lipids, having 58.68 mgg⁻¹d⁻¹ and 39.25 mgg⁻¹d⁻¹ of carbohydrate and lipid productivities, respectively. While winter cultivation conditions (22 ± 2 °C) favored higher protein productivity (34.49 mgg⁻¹d⁻¹) when compared to summer conditions. Additionally, in response to excessive nutrients and alkalinity (pH 10.0), it produced 180-198 mgg^-1 of phycobilins. Considering the multiproduct concept, the phycobilins were extracted and lipids from the residual biomass were converted to biodiesel and analyzed by gas chromatography-mass spectrometry (GC–MS). Intrestingly, phycobilin extraction had no negative impact on the quality and content of the biodiesel in the residual biomass. These features make the Plectonema terebrans BERC10 a promising candidate for the biological transformation of wastewater derived nutrients to biofuels and bioproducts.

在城市污水中培养光合微生物可能会由于污染物的去除，营养物质向生物产品的生物转化以及大气中的碳固着而有助于实现环境可持续性。蓝细菌是大气碳和微藻最有效的光合固定剂。本研究的重点是优化新分离的丝状蓝藻拟杆菌Plectonema terebrans BERC10的生长条件，以实现使用多种合成废水成分的多产品生物精炼厂提高的生物量和代谢产物生产率。140 mg L ^-1 d ^-1（干燥质量）的更高生物量生产率和250 mg L ^-1的CO ₂螯合速率通过模拟夏季（32±2°C）的耕作条件，实现了^-1天的工作，废水衍生的碱度（pH 10.0-11.0）进一步促进了这种情况。产生的生物质富含碳水化合物和脂质，分别具有58.68 mgg ^-1 d ^-1和39.25 mgg ^-1 d ^-1的碳水化合物和脂质生产率。与冬季条件相比，冬季栽培条件（22±2°C）有利于更高的蛋白质生产率（34.49 mgg ^-1 d ^-1）。此外，由于过量的养分和碱度（pH 10.0），它产生了180-198 mgg ^-1藻胆素。考虑到多产品概念，提取了藻胆素，并将残留生物质中的脂质转化为生物柴油，并通过气相色谱-质谱（GC-MS）进行了分析。有趣的是，藻胆素提取对残留生物量中生物柴油的质量和含量没有负面影响。这些特征使翼状柏（Plectonema terebrans BERC10）成为将废水中的营养物生物转化为生物燃料和生物产品的有希望的候选者。