Phytochemical characterization and cell-type-dependent biological effects of chokeberry ( Aronia melanocarpa ) extract: Cytotoxicity, apoptosis, telomere-related modulation and scratch-area response

Chokeberry ( Aronia melanocarpa ) is a polyphenol-rich berry with potential health-promoting properties. This study characterized a commercially available chokeberry extract and evaluated its effects on viability, apoptosis-related responses, relative telomere length (RTL), and scratch-area responses in HaCaT, L929, HCT-116, and HT-29 cells. The extract contained 4.02 mg GAE/mL total phenolics, 0.97 mg/L anthocyanins, predominantly cyanidin-3-O-galactoside (80.4%), and 1087 mg TEAC/100 mL antioxidant capacity. At 18 mg/mL, HCT-116 viability decreased to 64.5% at 24 h and 62.9% at 48 h, whereas HT-29 viability was not significantly affected. HaCaT generally maintained viability, while L929 showed a marked viability increase at 24 h but a reduction to 64.8% at 48 h at the highest concentration. No experimentally observed IC50 was reached within the tested concentration range (0.7–18 mg/mL). Apoptosis-related gene-expression responses were cell- and time-dependent and did not show a uniform pro-apoptotic transcriptional pattern. RTL-related qPCR responses were also cell- and time-dependent; L929 findings are exploratory because the assay was designed for human telomere quantification. Residual scratch area differed markedly among cell types, with the smallest residual area in L929 and almost no scratch-area reduction in HT-29 at 48 h. These findings support further investigation of chokeberry bioactivity while emphasizing the need for mechanistic, bioavailability, safety, and in vivo studies.