Micropropagation and screening of antioxidant potential of Andrographis paniculata (Burm. f) Nees

High frequency shoot proliferation via nodal explants of Andrographis paniculata was achieved in full and half strength MS medium with different concentrations of growth regulators. Half MS medium supplemented with 6-benzylaminopurine (1mg/l) and Adenine sulphate (1.5mg/l) gave a maximum average of 18.36 numbers of shoots after 45 days of culture. Rooting was achieved in Indole-3-acetic acid (0.5mg/l) after 7 days of culture. The regenerated plants were successfully acclimatized in the greenhouse and transferred to the field with 98% survival rate. The 8-months old field established micropropagated plants were evaluated for its antioxidant potential using 2, 2- diphenyl-1, picrylhydrazyl (DPPH) radical scavenging activity with various organic and aqueous solvents. Methanol extract gives a maximum percentage inhibition of 80.94% at 50 g/ml concentration. Antioxidant activity varies with the plant part used. IC50 value of A. paniculata leaf/stem, leaves, stem and roots were 30 g/ml, 35 g/ml, 40 g/ml and 45 g/ml respectively. The greater amount of flavonoid and phenolic compounds in A. paniculata leads to more potent radical scavenging effect.