Effect of Ethanol Percentage on Phytochemical Constituent, Antioxidant Activity, and Dermatological Potential of Cayratia trifolia (L.) Domin

Abstract

This study investigated the effect of different ethanol concentrations [0% (i.e., water), 50% ethanol, 70% ethanol, and 99.5% pure ethanol] on their ability to extract total phenolic (TP) and total flavonoid (TF) compounds, as well as their antioxidant activities and dermatological potential from the leaves of Cayratia trifolia (L.) Domin. The dried leaves were macerated for 24 hours at room temperature, followed by filtration and concentration of the extracts. The TP and TF contents were quantified using the Folin–Ciocalteu and AlCl3 methods, respectively. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays. Additionally, it evaluated the in vitro dermatological potential through tyrosinase and elastase inhibitory activities using colorimetric methods. The extract obtained with pure ethanol exhibited the most potent antioxidant activity, with IC50 values of 16.60 ± 0.62 µg/mL and 27.53 ± 0.69 µg/mL for the DPPH and FRAP assays, respectively. This extract also demonstrated the highest TP (3.82 ± 0.15 mg GAE/g DW) and TF (3.23 ± 0.09 mg QE/g DW) content. Furthermore, pure ethanol provided the highest extraction yield. However, the 70% ethanol extract emerged as a good source of tyrosinase (IC50, 60.49 ± 7.73 µg/mL) and elastase inhibitors (IC50, 45.49 ± 0.37 µg/mL). Overall, the results revealed that C. trifolia leaves are rich in polyphenols and flavonoids, demonstrating significant antioxidant activity when pure ethanol was used as the extraction solvent. Meanwhile, 70% ethanol showed the highest inhibitory activity against skin-related enzymes, tyrosinase and elastase. Future studies should aim to identify bioactive metabolites for use in cosmetic and medicinal formulations to address skin aging and hyperpigmentation.