Chromium-induced changes in ultramorphology and secondary metabolites of Phyllanthus amarus Schum & Thonn. – an hepatoprotective plant

Abstract

Chromium (Cr) concentration in the environment is increasing day by day due to its excessive use in leather processing, refractory steel, and chemical manufacturing industries. Excess Cr in the environment causes hazardous effects on all living beings including plants. In this context attempts have been made to see the effect of Cr on a very important medicinal plant Phyllanthus amarus Schum and Thonn. It has focused as a hepatoprotective plant curing hepatitis 'B' in modern research. The P. amarus seedlings of approximately same height and weight were grown in similar conditions in experimental garden. After 30 days plants were harvested and chlorophyll, protein, sugar, starch and secondary metabolites concentration were estimated in these plants as per standard methods. Besides ultramorphological variations in leaves and Cr accumulation in roots and aerial parts were also checked with the help of scanning electron microscope and atomic absorption spectrophotometer respectively. The study revealed that Cr causes significant decrease in fresh and dry weight, length of root and shoot, protein, sugar, chlorophyll and carotenoids in P. amarus. On the other hand it is interesting to note that the concentration of therapeutically active secondary metabolites - phyllanthin and hypophyllanthin increased up to certain level of Cr. It may be due to stress caused by the accumulation of Cr. Besides, ultramorphological changes viz. wide stomatal opening and less wax deposition on both the surfaces of leaves were also observed.