In vitro activity: Naringenin is a flavonoid that is considered to have a bioactive effect on human health as antioxidant, free radical scavenger, anti-inflammatory, carbohydrate metabolism promoter, and immune system modulator. Naringenin is the predominant flavanone in grapefruit. This substance has also been shown to reduce oxidative damage to DNA in vitro. Naringenin found in grapefruit juice has been shown to have an inhibitory effect on the human cytochrome P450 isoform CYP1A2, which can change pharmacokinetics in a human (or orthologous) host of several popular agents in an adverse manner, even resulting in carcinogens of otherwise harmless substances.

Cell Assay: Naringenin is dissolved in DMSO and diluted in cell culture medium. The cells are rinsed with PBS and grown in a medium containing various concentrations of naringenin (50, 100, 150, 200, 250, 300 μM). The solvent DMSO treated cells are served as control. After 24 hrs of treatment, the medium is removed and replaced by another medium containing MTT. Cell viability is measured using the MTT assay

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