Optimization of ultrasonic-assisted extraction of flavonoids and anti-oxidant capacity from the whole plant of Andrographis echioides (L.) nees by response surface methodology and chemical composition analysis Ramasamy J, Kandasamy R, Palanisamy S, Nadesan S. Optimization of ultrasonic-assisted extraction of flavonoids and anti-oxidant capacity from the whole plant of Andrographis echioides (L.) nees by response surface methodology and chemical composition analysis. Pharmacognosy Magazine . 2019;15(65):547-556.