Study of Antioxidant Activity and Correlation of Antioxidant Compounds in Eight Species of Garden Herbs

Abstract

Garden herbs grown around the house are used not only as food but also for
medicinal purposes. The objective of this study was to investigate the antioxidant activity,
antioxidant compounds, phenolic compounds, carotenoid and chlorophyll contents as
well as to study the correlation between these substances and antioxidant capacities in
eight species of garden herbs. The garden herbs were divided into two groups: 1) Fruitpart-
consumption (FC), namely Citrus x aurantiifolia (Christm.) Swingle, Passiflora laurifolia
L., Momordica cochinchinensis (Lour.) Spreng. and Solanum trilobatum L. and 2) Leaf-partconsumption
(LC), namely Pandanus amaryllifolius Roxb., Ocimum gratissimum L. var.
macrophyllum Briq., Piper sarmentosum Roxb. and Centella asiatica (L.) Urb. Antioxidant
activity and metabolite content between each species were compared using one-way
ANOVA and correlations between factors in each plant group were analyzed by Pearson
correlation. It was found that all of the eight species had antioxidant activity, with 50%
effective concentration (EC50) ranges from 2.24 ± 0.25 to 11.28 ± 0.71 mg mL-1.
S. trilobatum L. and P. laurifolia L. showed the highest antioxidant activity. Antioxidant
activity was correlated with antioxidant compound contents but no correlation was
observed with phenolic compounds and carotenoid contents in both FC and LC groups.
However, antioxidant activity in LC showed significant correlation with chlorophyll content
in leaves.