| Abstract
| - Lycopene, a lipophilic antioxidant, plays a crucial role in biological systems. It may play an importantrole in human biological systems by providing protection against cardiovascular disease and somecancers and by boosting the immune system. The oxygen radical absorbance capacity (ORAC) hasbeen validated as an index of antioxidant activity for many hydrophilic antioxidants but not for lycopene.This study validates the ORAC assay for different concentrations of lycopene in the presence ofβ-cyclodextrin, a water-solubility enhancer. Lyc-O-Mato 6% extract was used as a source of lycopenefor these experiments. Lycopene was extracted according to a standard spectrophotometric assayprocedure in the presence of β-cyclodextrin at concentrations of 0, 0.4, 0.8, and 1.6%, and theantioxidant activity of lycopene was measured with the ORAC assay. Experiments were conductedin quadruplicate and statistical pooled correlations analyzed. Statistical analysis showed a very highcorrelation (R2 = 0.99) between ORAC and ascorbic acid concentrations, validating this method.Lycopene concentration correlated poorly with ORAC (R2 = 0.33) in the absence of β-cyclodextrin.Correlations improved with increasing levels of β-cyclodextrin (R2 = 0.58 and 0.91 for 0.4 and 0.8%β-cyclodextrin, respectively). A very high β-cyclodextrin concentration (1.6%) decreased the correlationbetween ORAC and lycopene concentration. Inclusion of β-cyclodextrin in the ORAC assay improvescorrelation between ORAC and lycopene concentration, thus expanding the scope of the ORAC assayto include an additional fat-soluble antioxidant. Keywords: ORAC; lycopene; lipophilic antioxidants; β-cyclodextrin
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