Extract of Black Rice (Oryza sativa L. ‘Sembada Hitam’) Bran Protect Cytotoxicity of Hydrogen Peroxide on Vero Cells in a Short Time Incubation

Oxidative stress induced by hydrogen peroxide (H2O2) can lead to cellular damage, contributing to degenerative diseases and aging. Black rice bran is a functional food known
for its antioxidant properties, which are crucial in reducing the adverse effects of oxidative
stress and maintaining redox balance. In this study, we aimed to investigate the protective
effect of the extract of black rice bran (EBRB) 'Sembada Hitam' on Vero cells against H2O2
toxicity. To evaluate the protective effect, a co-culture method was employed, and cell
viability was assessed using the MTT assay. Additionally, cell growth was examined
through trypan blue staining. Vero cells were exposed to different concentrations of H2O2
and EBRB for a 24-hour period. The results demonstrated that EBRB at concentrations of
15.625, 250, and 500 μg/mL exhibited a protective effect on Vero cells exposed to H2O2
at concentrations of 100, 200, and 400 μM, respectively. Notably, when Vero cells were
treated with EBRB at concentrations of 250 or 500 μg/mL for five days in conjunction
with H2O2 exposure at concentrations of 200 or 400 μM for 24 hours, a significant decrease
in cell viability was observed on day 3. Based on the collective findings, it can be concluded that EBRB has the potential to protect Vero cells against H2O2 -induced toxicity,
but primarily during a short-term incubation period. Overall, this study highlights the protective properties of EBRB against H2O2 -induced cellular damage and emphasizes the
importance of further investigations to fully elucidate the underlying mechanisms and potential long-term effects of EBRB on cell viability.