Phytochemical profiling and in vitro sun protection factor evaluation of Phragmites australis

Abstract

Excessive exposure to solar ultraviolet (UV) radiation is a major environmental factor contributing to skin damage, oxidative stress, photoaging, and increased risk of cancer. Although synthetic sunscreens are widely used, concerns regarding safety, ecological impact, and long-term side effects have prompted growing interest in natural, plant-derived photoprotective agents. This study investigates the phytochemical composition and sun-protective efficacy of Phragmites australis, a perennial grass known for its diverse secondary metabolites. Whole plants were collected, authenticated, and subjected to pharmacognostic evaluation, physicochemical analysis, and preliminary phytochemical screening. Extracts were prepared using water, chloroform, and ethanol through cold maceration. Microscopic examination revealed diagnostic features including calcium oxalate crystals, lignified vessels, and mucilage cells, while physicochemical parameters indicated moderate moisture content (9.4%), total ash (4.5%), and high water-soluble extractives (9.23%). Phytochemical screening confirmed the presence of flavonoids, phenols, tannins, saponins, and glycosides, compounds known for antioxidant and UV-absorbing properties. The sun protection factor (SPF) was determined spectrophotometrically using the Mansur equation. Among the extracts, ethanol exhibited the highest SPF value (11.025 ± 0.022), followed by chloroform (2.2699 ± 0.003) and aqueous (1.5338 ± 0.016). These findings highlight the potential of Phragmites australis ethanolic extract as a candidate for further development as a natural, plant-derived UV-protective agent, combining antioxidant activity with in vitro UV-absorbing capacity. The study provides novel insights into the dermatological potential of Phragmites australis; however, as SPF was determined solely by in vitro spectrophotometry, these findings should be regarded as preliminary.