Analytical Methods for Standardization of Ayurvedic Asavas and Aristas; A Review

Plants serve as a rich source of bioactive molecules, which are used to treat various diseases in Ayurveda. Medicinal plant materials are formulated into valuable Ayurvedic medicines by application of modern scientific techniques, where standardization plays a pivotal role for authentication. Standardization confirms the identity, quality and purity of drugs. World Health Organization has set up suitable specific standardization parameters to evaluate the crude drugs and their finished products. These include various evaluation techniques such as pharmacognostical, physico-chemical, phytochemical, analytical, biological and biotechnological. Nowadays, application of several modern analytical techniques have become inevitable for evaluating the polyherbal Ayurvedic formulations to ensure quality, safety and efficacy. Various spectroscopic and chromatographic methods applicable for this purpose are ultra-violet spectroscopy, Fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, thin-layer chromatography, high performance thin layer chromatography, high performance liquid chromatopgraphy, gas chromatography, mass spectroscopy and hyphenated techniques such as gas chromatography-mass spectroscopy, liquid chromatography-mass spectroscopy, liquid chromatography-nuclear magnetic resonance spectroscopy. Out of several formulations available in Ayurveda, asavas and aristas are considered as unique dosage forms due to their indefinite shelf life. Standardization of different asava-arista formulations using various analytical techniques are vividly discussed in this review.