ANTHOCYANIN AND POTENTIAL THERAPEUTIC TRAITS IN CLITORIA, DESMODIUM, CORCHORUS, CATHARANTHUS AND HIBISCUS SPECIES

Abstract

The USDA, ARS, Plant Genetic Resources Conservation Unit curates several important nutraceutical and medicinal plant species. Anthocyanins are responsible for flower, leaf and seed coat color in plants, and are antioxidants as well. However, little is known about anthocyanin content in Clitoria ternatea, Desmodium adscendens, Corchorus olitorius, Catharanthus roseus, Hibiscus sabdariffa and Acer saccharum. This study was conducted to identify anthocyanin indexes and additional health enhancing components in these species. An anthocyanin meter with an LED diode of 520 nm was used to measure the anthocyanin index of leaves and flowers from plants growing in the field during July, September and October 2006. We found anthocyanin indexes ranging from 4.1 to 52.4 for leaves and 0.8 to 26.8 for flowers in all five species. The highest leaf anthocyanin index average of 14.6 was found in D. adscendens (PI 316623) followed by sugar maple (A. saccharum) with a leaf anthocyanin average index of 13.0. Catharanthus roseus (PI 608581) also had the highest flower anthocyanin index average of 17.3. These data were recorded at or prior to 50% maturity. In addition, potential health uses for these species are discussed. Phytochemicals identified include but are not limited to an antimicrobial protein from C. ternatea, anthocyanin rich extracts from H. sabdariffa for potential use as a chemopreventive agent, and antitumor promoters in C. olitorius leaves. These anthocyanins and phytochemicals have potential value in the nutraceutical and medical industries. These variable anthocyanin indexes among these species will assist breeders and other scientists with valuable germplasm for development of anthocyanin enriched cultivars.