Cholinesterase inhibitory activity, antioxidant properties, and phytochemical composition ofChlorococcumsp. extracts

In this study,Chlorococcumsp. was investigated for its cholinesterase inhibitory potentials and antioxidant activity. The algal sample was cultivated, harvested, and extracted sequentially using n-hexane, dichloromethane, and ethanol. The extracts were characterized using Fourier transmission infra-red (FTIR) and Gas Chromatography-Mass Spectrometry. The metal chelating, radical scavenging activities, as well as anticholinesterase potentials of the algal extract, was also investigated. FTIR characterization of the microalgal biomass revealed the presence of phenolic compounds, alkaloids, polysaccharides, and fatty acids. The extracts showed the presence of phytol, neophytadiene, butylated hydroxyl toluene, and 3-tert-butyl-4-hydroxyanisole. The ethanol extract showed the highest DPPH (IC50 = 147.40 mu g/ml) and OH (IC50 = 493.90 mu g/ml) radical scavenging and metal chelating (IC50 = 83.25 mu g/ml) activities. Similarly, the ethanol extract (IC50 = 13.83 mu g/ml) exhibited the highest acetylcholinesterase inhibitory activity, while the dichloromethane extract showed the highest butyrylcholinesterase inhibitory activity. All the extracts exhibited antioxidant properties and inhibitory effects against butyrylcholinesterase and acetylcholinesterase; however, ethanol extracts showed better activity. Practical applications Biomass obtained from some microalgal species is commonly used as dietary supplements and nutraceuticals due to the presence of high-valued products. However, the antioxidant and anticholinesterase activities of biomass fromChlorococcumsp. have not been explored.Chlorococcumsp. extracts contain some antioxidants such as 3-tert-Butyl-4-hydroxyanisole, butylated hydroxytoluene, phytol, and neophytadiene. Characterization of the extracts also revealed the presence of phenolic compounds, polysaccharides, and fatty acids. These compounds may contribute to the observed antioxidant and anticholinesterase activities ofChlorococcumsp. The result of this study suggests thatChlorococcumsp. may contain some nutraceuticals which could be used as antioxidants and cholinesterase inhibitors.