Enhancement of radical intensity and cytotoxic activity of ascorbate by Crataegus cuneata Sieb et. Zucc. extracts.

The radical modulation activity of hot water and NaOH extracts of the thorn apple of Crataegus Cuneata Sieb. et. Zucc. was investigated, using ESR spectroscopy. The radical intensity of sodium ascorbate was slightly reduced at lower concentrations of the extracts, but it was synergistically enhanced at higher concentrations. Higher concentrations of the extracts also synergistically stimulated the cytotoxic action of sodium ascorbate against human oral squamous carcinoma and salivary gland tumor cell lines. All these extracts effectively scavenged superoxide anion and hydroxyl radical, produced by hypoxanthine-xanthine oxidase and Fenton reaction, respectively, and their activity was comparable with that of lignins prepared by the same procedure from other plants. These data further supports the medicinal efficacy of plant extracts.