Antioxidant activity of phenolic compounds from extracts of <italic>Eucalyptus globulus</italic> and <italic>Melaleuca styphelioides</italic> and their protective role on D-glucose-induced hyperglycemic stress and oxalate stress in NRK-49Fcells.

Phytochemicals serve as potential therapeutic agents for the prevention and treatment of diseases. In this study, we elucidate the renoprotective activity of compounds isolated from <italic>Eucalyptus globulus</italic> and <italic>Melaleuca styphelioides</italic> extracts in glucose- and oxalate-challenged NRK-49F cell model. The antioxidant potential of isolated compounds was evaluated based on their effect on antioxidant enzyme activities and lipid peroxidation levels. The results demonstrated that exposure of NRK-49F cells to glucose and oxalate stress augmented cell damage and attenuated antioxidant enzyme activities. The phytochemicals 2,2,8-trimethyl-6-formyl-chrom-3-ene-7-<italic>O</italic>-β-D-glucopyranoside, Cornusiin B and tellimagrandin I treatment restored antioxidant enzyme activity, significantly lowered lipid peroxidation levels and effectively protected cells from glucose and oxalate stress equivalent to the known antioxidant, <italic>N</italic>-acetyl cysteine. Pterocarinin A significantly reversed cellular damage owing to glucose stress. In conclusion, the compounds isolated from <italic>E. globulus</italic> and <italic>M. styphelioides</italic> showed potential cytoprotective and anti-oxidative property against glucose- and oxalate-induced oxidative stress in NRK-49F cells. [ABSTRACT FROM AUTHOR]