Antioxidant activity and mineral content of Impatiens tinctoria A. Rich (Ensosila) tuber, an Ethiopian medicinal plant

Recently, an interest has surged in incorporating extracts of medicinal plants as active ingredients in cosmetic formulations, highlighting the need to analyze medicinal plants of cosmetic interest for phytochemicals and bioactivities. The tuber of the Ethiopian medicinal plant Impatiens tinctoria A. Rich (Ensosila) is used to make traditional cosmetics. The aim of the study was to investigate the antioxidant and mineral content of the Impatiens tinctoria tuber. Water, ethanol, and methanol were used during the extraction process. High phenolic content was found in methanol extract (107.8 ± 0.025 µg/ml GAE) followed by water extract (92.4 ± 0.02 µg/ml GAE). High flavonoid content was also obtained in methanol extract (136.7 ± 0.04 µg/ml QE). Strong 2,2-diphenyl-1-picryl-hydrazyl (DPPH) scavenging activity was recorded for methanol extract with IC50 value of 44.4 µg/ml, compared with ethanol extract (97.54 µg/ml) and water extracts (98.24 µg/ml). The lower IC50 value of methanolic extract demonstrated strong antioxidant activity. The three elements that were most prevalent in Impatiens tinctoria tuber out of the eight elements examined were K (170 ± 0.05 mg/100 g sample), Ca (87 ± 0.08 mg/100 g sample), and Mg (16 ± 0.01 mg/100 g sample). The phenolics, flavonoids, and minerals found in Impatiens tinctoria A. Rich (Ensosila) tuber may protect against oxidative stress-related skin damage and thus deserving attention for future applications in cosmetics formulations.