Polyphenolic Composition and Antioxidant Capacity of Home-brewed Plum, Cherry, Rhododendron, and Grape Wines

ABSTRACT: Fruit and flower wines have been studied for their various polyphenols. Among them, red wines are the most widely studied for their flavonoid and polyphenol content. Thus, the present study aims to assess the polyphenolic contents and antioxidant capacity of home-brewed plum, cherry, grape, and rhododendron wines. The total polyphenolic contents and flavonoids of the wine samples were quantified using Folin-Ciocalteu, Folin-Denis, and aluminum chloride methods, respectively. Antioxidant activity was assessed through ABTS and DPPH assays. Additionally, the ability of the wine samples to mitigate lipopolysaccharide-induced reactive oxygen and nitrogen species was investigated in a RAW 264.7 murine macrophage cell line using dichlorodihydrofluorescein diacetate and Griess reagents, respectively. Rhododendron wine displayed the highest content of total polyphenolic compounds (383.33±18.75 µg/mL tannic acid equivalent) and the highest flavonoid content (167.75±9.53 µg/mL quercetin equivalent). Rhododendron and plum wines showed significant reducing power (1723.83±143.19 µg/mL and 1675.66±10.29 µg/mL quercetin equivalent antioxidant capacity, respectively) and free radical scavenging activity (82.16±7.38% and 78.2±9% respectively). All four wines significantly reduced the reactive oxygen and nitrogen species formation in lipopolysaccharides-induced macrophages. This study indicates that plum, cherry, and rhododendron wines exhibit notable in vitro antioxidant potential, highlighting their capacity to enhance revenue within the fruit wine market.