Total phenols and vitamin C contents of Iranian fruits

Abstract

Purpose

The antioxidant characteristics of fruits can be attributed to their contents of polyphenols and vitamins. Because of the interest in the role of antioxidants in human health, the purpose of this paper is to examine the major compounds associated with antioxidant activity, namely total phenolic and vitamin C contents, of some regularly cultivated and consumed fruits in Iran.

Design/methodology/approach

In total, 66 fruits from 22 families were chosen for this study. Terbium sensitized fluorescence assay and spectrophotometric method were used to determine total polyphenol and vitamin C contents respectively. The ANOVA with Tukey post‐hoc test was used for statistical analyses.

Findings

The total mean polyphenol content of fruits was 4.93 ± 2.86 mg QE/100 g that were ranging from 0.8 ± 0.05 to 11.94 ± 0.02 mg QE/100 g with the lowest amount obtained for pear and the highest amount detected in black grape. The polyphenol contents of black grape, sourcherry and pomegranate were significantly higher than those of other fruits (p < 0.001). The total mean vitamin C content of fresh fruits was 18.34 ± 9.77 mg/100 g that were ranging from 57.38 ± 0.02 (strawberry) to 11.44 ± 0.02 (melon) mg/100 g. The vitamin C contents of strawberry was significantly higher than all other fruits (p < 0.001). Despite the differences in the polyphenol and vitamin C contents of various fruits, as a good source of nutritious compounds and functional foods, they can be effective in enhancing health status.

Originality/value

This paper is believed to be the only one which provides information about the polyphenol and vitamin C contents of Iranian fruits. Also, the polyphenol content was measured by using a newly‐developed method.

Citation

Nikniaz, Z., Mahdavi, R., Rafraf, M. and Jouyban, A. (2009), "Total phenols and vitamin C contents of Iranian fruits", Nutrition & Food Science, Vol. 39 No. 6, pp. 603-608. https://doi.org/10.1108/00346650911002922