@article{Valisakkagari2026, 
author = {Harichandana Valisakkagari and H.P. Vasantha Rupasinghe},
title = {Bioactive-rich kale extracts protect against UV-induced oxidative stress and DNA damage in human skin fibroblasts},
year = {2026},
journal = {Journal of Food Bioactives},
volume = {33},
pages = {63-72},
keywords = {Food bioactives, Brassica oleracea var. acephala, Skin health, Phytochemicals, Cosmeceuticals},
url = {https://www.sciopen.com/article/10.26599/JFB.2026.95033440},
doi = {10.26599/JFB.2026.95033440},
abstract = {Exposure to ultraviolet (UV) radiation causes oxidative stress and DNA damage in skin cells. This study investigated the protective effects of bioactive-rich extracts prepared from upcycled kale powder using UV-induced human skin fibroblasts (WS1 cells) in vitro. The extracts were prepared using ultrasound-assisted extraction [K(U)] and microwave-assisted extraction [K(M)]. The Fourier transform infrared spectroscopy (FT-IR) and ultra-high-performance liquid chromatography electrospray ionization mass spectrometry (UPLC-ESI-MS) demonstrated that K(M) contains higher concentrations of major bioactive phytochemicals, including phenolic acids, carotenoids, glucosinolates and flavonoids, than K(U). Both extracts contributed to higher cell viability (>80%) at concentrations of 1, 10, and 100 µg/mL compared to the UV-exposed control. Furthermore, the kale extracts and all tested phytochemicals (0.001-100 µg/mL) significantly reduced UV-induced reactive oxygen species (p < 0.05) compared to the UV-treated control. UV irradiation increased DNA damage, while K(U) at 0.01 and 0.1 µg/mL, chlorogenic acid at 0.1 µg/mL, and sulforaphane at 0.001 and 0.01 µg/mL significantly reduced DNA damage compared to the UV-treated control, as determined using phosphorylated H2A histone (γ-H2AX) immunofluorescence assay. Therefore, phytochemical-rich kale extracts demonstrate potential in protecting skin fibroblasts from UV-induced oxidative stress and DNA damage, suggesting potential applications in cosmeceutical formulations for skin protection against UV radiation.}
}