Isolation, identification and quantification of gallic acid (gallotannins) through HPTLC in leaf galls of Madhuca longifolia (Koenig) j.f. Macb

Abstract

Plant galls (cecidia) are pathologically produced cells, tissues, or organs of plants that have developed by hypertrophy and hyperplasia of plant tissues under the effect of gall causing organisms. Madhuca Longifolia (Koenig) j.f Macb. is an economically and medicinally very important plant of the family Sapotaceae. It is a tropical mixed deciduous tree. Various galls due to insect infestation are found on almost all tree species. Leaf galls of Madhuca longifolia induced by insects of order Diptera and Hymenoptera represent a unique pattern of chemical perturbations which normally do not occur in normal leaf. During the present investigation, an accurate, fast and easy HPTLC method was followed for quantification of gallic acid occur in the normal leaf and dried leaf galls of the Madhuca longifolia  plant. The protocol followed in this study resulted in an intense peak and was able to give a good resolution of gallic acid from normal leaf and galled tissues of Madhuca longifolia (Koenig) j.f. Macb. Adaxial leaf gall induced by insect Mohwadiplosis Orientalis Rao belonging to Diptera class, Marginal gall induced by another Dipteran and vein gall by chalcidoiid Hymenopteran class of insect. Variation in Gallic acid present in normal leaf and leaf galls of Madhuca longifolia  was critically reported. It was found that Gallic acid content increased almost two folds in gall tissues as compared to normal leaf tissue. Galled  leaf (Dipteran adaxial gall) had a maximum amount of Gallic acid (344.4 ng) while in normal leaf and another leaf galls had less amount of gallic acid was found (180 ng). This study is of practical importance because gallic acid is the most important active phenolic acid, which may be correlated with post-infection biochemical defense. Compound gallic acid has been reported for the first time from leaf galls of Madhuca longifolia (Koenig) j.f. Macb. Plant in the study.