Effect of different extraction solvents on antioxidant properties of water lily (Nymphaeaceae antares) flower petal and stamen

Water lily (Nymphaeaceae antares) contains a vast array of phenolic compounds with important natural antioxidative properties that could inhibit the adverse effects of the reactive oxygen species produced in living things. These substances are complex in composition which requires a suitable extraction medium to exploit the phenolic compounds. This study was designed to determine the antioxidative properties in petal and stamen of water lily extracted using different extraction solvents namely ethyl acetate and 60% methanol. Antioxidant properties of the samples were determined using 2,2-diphenyl -1-picrylhydrazyl (DPPH) radical scavenging activity, ferric thiocyanate (FTC) method, thiobarbituric acid (TBA) test, total phenolic content (TPC), total flavonoid content (TFC) and total tannin content (TTC) along with individual flavonoids content using High Performance Liquid Chromatography (HPLC). The yield of extract was found to be the highest in petals extracted with 60% methanol (44.55±1.63%) while stamen extracted with ethyl acetate yielded the lowest (24.50±1.09%). In the DPPH inhibition method, petal extracted with ethyl acetate obtained the highest scavenging activity (89.15±3.62%). FTC analysis revealed that ethyl acetate extract of petal experienced the highest percentage inhibition (76.70±6.48%) while in TBA analysis ethyl acetate extract of stamen exhibited the highest percentage inhibition (70.78±1.39%). Flavonoids such as quercetin, kaempferol, rutin, gallic acid, catechin, epigallocatechin, p-coumaric acid and myricetin were found to be present in ethyl acetate and 60% methanol extracts of water lilies stamen and petal. The information from this study indicates that water lily petals and stamens may be integrated as a good source of nutrients in the food industry, the pharmaceutical industry. If the advantages of water lily are not used and integrated into everyday life for health benefits, it will be a massive waste of natural resources.