Sustainable production of bioactive compounds and biodiesel from <i>Scenedesmus obliquus</i> cultivated in organic waste‐based media

Abstract The cultivation of microalgae to produce biofuels and other value‐added products constitutes a compelling biotechnological and sustainable alternative. This study assessed the production of pigments, proteins, carbohydrates, lipids, and fatty acid methyl esters by Scenedesmus obliquus cultivated in various alternative media (AM) derived from four types of manure digestate: swine (SD), cattle (CD), a combination of swine and cattle, and different stable manures (FD), in addition to vermicompost tea and vermicompost leachate, comparing these findings with the standard Bold’s Basal Medium (BBM). All the AM enhanced the production of carbohydrates and lipids relative to BBM, except for FD, which did not exhibit a substantial increase in carbohydrates. The CD and FD media enhanced protein production by 28.37% and 24.9%, respectively, in comparison with BBM. In the AM, 12 fatty acids were found, whereas only three were recognized in the BBM. The biodiesel produced from AM satisfied all of the specified quality metrics, except for the SD medium, which exhibited a superior cetane number but failed to fulfill all criteria; conversely, the biodiesel sourced from BBM met four of the standards. The results indicate that manure digestates are appropriate substrates for the cultivation of S. obliquus , as they promote the synthesis of value‐added chemicals and facilitate the generation of high‐quality biodiesel. The utilization of unconventional methods represents an approach that reduces environmental impact and may lower production costs, hence improving process sustainability.