Effect of Extraction Solvents on Yield, Mineral Composition, Phytochemical Constituents, Antioxidant and Antimicrobial Properties of Chrysophyllum albidum (African Star Apple) Leaf

Abstract

Chrysophyllum albidum is a tropical plant that belongs to the family Sapotaceae with about 800 species that make up almost half of the order Ericales The yield, mineral, phytochemical constituents, antioxidant and antimicrobial properties of different solvent extracts of Chrysophyllum albidum leaves were investigated. The leaves of C. albidum were successively extracted in acetone, ethyl acetate, petroleum ether, ethanol and distilled water. All obtained crude extracts were evaluated for yield, minerals, phytochemical constituents, free radical scavenging (2, 2-diphenyl-1- picryl hydrazyl - DPPH and Ferric Reducing Antioxidant Power Assay-FRAP) activities and antimicrobial properties. The ethanol extract has the best yield (10.41%) while petroleum ether has the least (2.22%). Phytochemical screening of the crude extracts showed the highest presence of tannin (4.25±0.01), total phenolic content (77.48±0.02) and flavonoid (18.39±0.06) in acetone extract, saponin (1.43±0.30) and alkaloid (3.76±0.10) were highest in aqueous extract while all were absent in petroleum ether extract. Aqueous extract showed a higher presence of magnesium (6.103±0.00), potassium 27.578±0.00), sodium (2.969±0.00), zinc (0.036±0.00) and manganese (0.082±0.00) except calcium (1.001±0.00) that was higher in ethyl acetate extract and iron (0.161±0.00) in acetone extract. The antioxidant activity of Acetone (IC = 83.10±0.52 ?g mL) and ethanol (IC = 86.71±0.06 ?g mL) extract showed 2, 2-diphenyl-1- picryl hydrazyl (DPPH) scavenging activity which was comparable with that of standard ascorbic acid (IC = 95.14±0.51 ?g mL). Ferric Reducing Antioxidant Power Assay (FRAP) scavenging activity showed a maximum effect in acetone extract while the least was observed in pet ether extract. The in vitro antimicrobial activity was done by agar disc diffusion method against Staphylococcus aureus, Aeromonas hydrophila, E. coli, Pseudomonas aeruginosa, Salmonella spp, and Bacillus spp. Maximum -antibacterial activity (zone of inhibition) was shown by acetone and ethanol extracts against all the tested organisms whereas ethyl acetate extract showed no activity. This study has revealed that the leaf extracts of C. albidum possess potent phytonutrients, antioxidants and free radical scavenging activity which may be due to the presence of flavonoids and total phenolic content (TPC) as well as antimicrobial effects against some of the tested bacteria.