Screening of efficient growth modulators for task-specific enhancements in microalgal cultivation

Abstract

Microalgae are an abundant source of value-added metabolites and have emerged as a promising feedstock in food, medicine, and bioenergy sectors. However, low biomass productivity and metabolite content are major neck bottle problems in commercializing microalgal-based bio products. The conventional and genetic engineering tactics to improve microalgal productivity remain challenging due to compromised growth and high maintenance costs. To overcome these issues, the concept of efficient chemical stimulants has emerged as a topic of intense research in the microalgal cultivation domain. In this study, 55 chemicals with different physiological roles have been screened using Scenedesmus sp. as a target. A two-phase screening was performed to identify the best chemical stimulants; phase I was performed with 96-well culture plates. Chemicals showing increased growth were further studied in phase II. Phase II screening was carried out in 250 mL culture volume. Chemicals such as benzoic acid (BA), salicylic acid (SA), and folic acid (FA) enhanced the biomass and/or biochemical portfolio of Scenedesmus sp.