Exploration of the phytohormone regulation of energy storage compound accumulation in microalgae

Abstract

Microalgal energy storage compounds (carbohydrates, lipids, etc.) can serve as renewable feedstocks for biofuels and biobased chemicals. Traditional methods of inducing the accumulation of energy storage compounds in microalgae, such as abiotic stress (high light intensity, high salinity, nutrient limitation, heavy metals, etc.), can affect the growth of microalgae and limit their efficient accumulation of energy storage materials. Plant hormones are a class of small molecular substances that act as chemical messengers to coordinate plant cell activities and regulate the physiological and metabolic activities of microalgae, including promoting microalgal cell proliferation, improving stress resistance, and enhancing photosynthetic activity, thereby increasing algal biomass and lipid, chlorophyll and protein content. This paper reviews the recent research progress on regulation of the accumulation of energy storage compounds in microalgae by adding exogenous plant hormones combined with abiotic stress, discusses the mechanism of plant hormones regarding the accumulation of energy storage compounds in microalgae, and proposes future research needs.