Optimization of Solvent Concentrations for Optimum Extraction of Polyphenols, Flavonoids, and Antioxidant Activity from Physalis peruvianaL. Fruit Extracts

Introduction: This study aimed to evaluate the impact of solvent type and concentration on the extraction efficiency of phenolic and flavonoid compounds, as well as the antioxidant activity of Physalis peruviana L. fruit. Various solvent systems (methanol, ethanol, and aqueous) at different concentrations (30%, 50%, 70%, and 90%) were employed to determine their effectiveness in extracting bioactive compounds. Methods: Ripe P. peruviana berries were carefully selected based on uniformity in color, size, and maturity. The fruits were sliced into small pieces, dried at 45°C, ground into a fine powder, and sieved. The resulting powder was stored in airtight containers at 4°C for further analysis. Total phenolic content (TPC) and total flavonoid content (TFC) were determined using the Folin- Ciocalteu method and Aluminium chloride method, respectively. Antioxidant activity was evaluated using DPPH radical scavenging, metal chelating, and hydrogen peroxide (H₂O₂) scavenging assays in different extract samples with different solvent systems, including methanol, ethanol, and aqueous solutions at different concentrations (30%, 50%, 70%, and 90%) using a spectrophotometer. Results: Among the tested solvents, 90% methanol demonstrated the highest extraction efficiency, yielding the highest phenolic content (73.725 ± 0.39 mg GAE/g) and flavonoid content (118.625 ± 0.33 mg QE/g). Additionally, this solvent exhibited superior antioxidant activity, as evidenced by its high FRAP value (14.56 ± 0.25 mM Fe²⁺E/g), DPPH radical scavenging capacity (78.27 ± 1.4%), reducing power (0.5 ± 0.013 μM AAE/g), and metal chelating activity (72.77 ± 0.053%). Linear regression analysis confirmed a strong positive correlation between the phenolic and flavonoid content and the antioxidant properties of the extracts. Discussion: Comparative analysis indicated that aqueous ethanol and methanol extracts exhibited stronger antioxidant activity and higher concentrations of bioactive compounds than aqueous extracts, which were the least effective. The statistically significant correlation between total phenolics, flavonoids, and antioxidant activity highlights the role of these compounds in the antioxidant potential of P. peruviana. Conclusion: The findings suggest that 90% methanol is the optimal solvent for extracting phenolic and flavonoid compounds, yielding the highest antioxidant activity. These results have significant implications for the nutraceutical, pharmaceutical, and food industries, emphasizing the potential of P. peruviana as a valuable source of bioactive compounds. Optimizing solvent extraction techniques could facilitate its incorporation into functional foods, dietary supplements, and medicinal formulations, enhancing its commercial and therapeutic applications.