Antioxidant and phytochemical levels and their interrelation in stem and leaf extract of water spinach (Ipomea aquatica)

Abstract

An investigation was carried out to evaluate nutritional and anti-oxidant properties of leaf and stem extracts from 10 genotypes of water spinach (Ipomea aquatica Forsk). The extracts were analyzed in terms for protein, sugar, chlorophyll, carotenoid, phenol, proline, flavonoids and ascorbic acid contents. The analysis revealed a significant variation in the level of protein (10.4-151.6 mg/g FW), sugar (0.33-2.98 g/100g FW), chlorophyll (2.50-4.98 mg/g FW), phenol (0.75-2.11 mg/g FW), proline (0.14-36.14 μg/g FW), carotenoid (0.85-0.1.59 mg/g FW), flavonoid (0.1-0.431 mg/g FW) and ascorbic acid (0.21-1.03 g/100g FW) in leaf extract and (protein 13.1-144.8 mg/g FW, sugar 0.43-3.55 g/100g FW, chlorophyll 0.32-0.76 mg/g FW, phenol 0.54-4.76 mg/g FW, proline 0.09-29.46 μg/g FW, carotenoid 0.12-0.29 mg/g FW, flavonoid 0.05-0.231 mg/g FW and ascorbic acid 0.28-0.62 g/100g FW) in stem extract of the genotypes. The results indicate that total sugar, proline and protein in both stem and leaf extracts expressed high heritability coupled with high genetic advance indicating that these traits are mainly controlled by additive genes and progeny selection will be rewarding for improvement of these traits. High heritability values in these traits indicate that expression of characters under study is less influenced by environment. Plant breeders on such basis may make the safe selection on the basis of phenotype of the plant by adopting simple selection schemes. For most of the nutritional and anti-nutritional qualities the genotypic correlation coefficient was recorded higher than phenotypic correlation coefficient. The study indicates significantly less influence of environment on the expression of these nutritional and antioxidant traits.