Phenolic Profile and Antioxidant Potential of Aqueous Extracts of Selected Traditional Anti-cough Plants

Abstract

The recent surge in attention towards plant-based antioxidants can be attributed to their perceived advantageous impact on human health. The present study assessed the phenolic profile, antioxidant potential, and free radical scavenging ability of hot aqueous leaf extracts obtained from Vernonia amygdalina, Piper guineense, and Gongronema latifolium. High-Performance Liquid Chromatography (HPLC) was used to examine phenolic profile. Antioxidant capacity was conducted using total flavonoid content (TFC), total phenol content (TPC), total antioxidant capacity (TAC), polyphenol oxidase (PPO) activity, while ferric reducing antioxidant potential (FRAP), nitric oxide (NO), hydroxyl (OH), and 2, 2-diphenyl-2-picrylhydrazyl (DPPH) were analysed for their radicals scavenging activities. G. latifolium displayed notable phenolic compounds, such as lunamarin (76.32mg/ml), ribalinidine (64.08 mg/ml), gallocatechin (48.58mg/ml), aglycone (41.69 mg/ml), flavonone (33.45mg/ml), and flavan-3-ol (30.49mg/ml). The plant extracts contained resveratol, kaempferol, and ribalinidine in a consistent manner across all samples. The findings suggest that the plants exhibits noteworthy antioxidant potential, with G. latifolium displaying the highest antioxidant capacity (96.18 ± 0.11µg/mL) and total phenolic content (28.50 ± 0.04 µg/mL). V. amgydalina showed highest polyphenol oxidase activity, at 7.14 ± 0.10 µg/mL G. latifolium as well showed high •NO scavenging radicals and FRAP activity, while exhibiting the least efficacy in •OH scavenging radicals. The results indicate that all three samples demonstrated a noteworthy increase in DPPH scavenging activity, which was statistically significant at p<0.05 compared to standard. Results reveals that plant extracts showed significant phenolic compounds, antioxidant and free radicals property. These observations provides a rationale for the traditional use of these extracts in folk medicine for management and treatment of cough.
 Keywords. Gongronema latifoluim, Veronia amygdalina, Piper guineense, Phenolic profile, Antioxidant capacity, Free Radical, cough.