Andrographolide production and enhanced antioxidant activity in Andrographis paniculata (Burm f.) Nees. promoted by seaweed liquid extracts

Andrographolide is important specialized metabolites of Andrographis paniculata (Acanthaceae) which is used to treat wide array of disorders such as cancer, diabetes, rheumatoid arthritis. An attempt was made to examine the potential of seaweed (Sargassum wightii Greville) on growth, andrographolide content and antioxidant activity in A. paniculata. Different concentrations (5%, 10%, 15% and 20%) of seaweed liquid extract (SLE) were applied through foliar application to A. paniculata (Burm. f.) Nees seedlings. Among the various concentrations, 10% of SLE exhibited a maximum increase in growth parameters such as plant height (113%), leaf surface area (129%), number of leaves and branch by 134% and 118%, fresh weight (178%) and dry weight (220%). Similarly, biochemical constituents such as starch (132%), glucose (122%), protein (177%) and total chlorophyll (213%) were also found to be enhanced in leaves of those plants which received 10% of SLE. A twofold (34.92 mg g−1) increased synthesis of andrographolide was noticed in 10% methanolic SLE treated plants. Similarly, antioxidant activity was increased in 10% methanolic SLE which accounted for 53.94 μg/ml DPPH activity and 44.94% inhibition of nitric oxide activity. The present study suggested that SLE of S. wightii could be a promising biostimulant which can be attributed to the presence of growth hormones like cytokinin (3.9 mg L−1), auxin (3.0 mg L−1) and gibberellin (2.2 mg L−1) and nutrients such as Na (45.47 mg L−1), Mg (75.12 mg L−1), P (4.03 mg L−1), K (58.4 mg L−1), Ca (0.432 mg L−1), Fe (0.85 mg L−1), Cu (0.346 mg L−1), Mb (0.0004 mg L−1) and N (2.56%) and also pave the way for sustainable environment approach in herbal cultivation.