In this study, seven different cyanobacteria (LS01-LS07) were isolated from paddy field water and among them, the isolate LS04 was able to grow well on municipal wastewater. The LS04 isolate was identified as Nostoc sp. (designated as Nostoc sp. LS04) based on 16S rRNA gene sequence analysis. Strain LS04 grew well in 75% wastewater and had the greatest nutrients removal efficiency (81.02–95.17%). Strain LS04 obtained the higher biomass (1.31 ± 0.08 g L⁻¹) and productivity of 131.33 ± 8.08 mg L⁻¹ d⁻¹. The lipid content and productivity of LS04 were 14.85 ± 0.86% (dry cell weight) and 19.46 ± 0.05 mg L⁻¹ d⁻¹, respectively. The high proportion of C16–C18 fatty acids found in the lipids of LS04 indicated the high suitability for biodiesel production. In addition, Nostoc sp. LS04 cellular extracts were potentially used as a biostimulant for Lactuca sativa cultivation. The foliar application of 60% LS04 cellular extracts showed the maximum shoot length, root length, fresh biomass, dry biomass, Chl a, Chl b and carotenoids in lettuce plants compared to control plants. Similarly, 60% of LS04 cellular extracts treatment improved the concentrations of macro and micronutrients, and biochemical compounds in the leaves. Therefore, these results reveal that the Nostoc sp. LS04 is a promising candidate for the nutrients removal from wastewater and their biomass is a potential resource for biodiesel production and biostimulant for sustainable crop production.

本研究从稻田水中分离出七种不同的蓝藻（LS01-LS07），其中LS04能够在城市废水中生长良好。 LS04 分离株被鉴定为发菜属 ( Nostoc sp.)。 （命名为Nostoc sp. LS04）基于16S rRNA基因序列分析。菌株LS04在75%的废水中生长良好，并且具有最大的营养物去除效率（81.02-95.17%）。菌株LS04获得了较高的生物量（1.31±0.08 g L ^-1 ）和131.33±8.08 mg L ^-1 d ^-1的生产力。 LS04的脂质含量和生产率分别为14.85±0.86%（细胞干重）和19.46±0.05 mg L ^-1 d ^-1 。 LS04 脂质中 C16-C18 脂肪酸的比例很高，表明其非常适合生产生物柴油。此外，发菜sp。 LS04 细胞提取物有可能用作莴苣种植的生物刺激剂。叶面施用 60% LS04 细胞提取物显示，与对照植物相比，生菜植物具有最大芽长、根长、新鲜生物量、干生物量、叶绿素a 、叶绿素b和类胡萝卜素。同样，60% 的 LS04 细胞提取物处理提高了叶子中常量和微量营养素以及生化化合物的浓度。因此，这些结果表明发菜sp。 LS04 是去除废水中养分的有前途的候选者，其生物质是生物柴油生产和可持续作物生产的生物刺激剂的潜在资源。