Effect of seasonal variations on the phytoconstituents of Aśvagandhā w.r. to lunar cycles

INTRODUCTION: Suśruta, Caraka and other ācāryas advocate the collection of medicinal plants keeping in view the part used, season, soil in which the herb grows and the desired pharmacological actions or therapeutic benefits. The logic behind such recommendations is being validated by modern scientific research. AIM: To assess the effect of seasonal variations on the phytoconstituents of Aśvagandhā (Withania somnifera L. Dunal) w.s.r. to lunar cycles. MATERIAL AND METHODS: The plant specimens were collected from Jamnagar identified pharmacognostically and cultivated under a defined habitat in a herbal garden of IPGT and RA on 7 Oct 2013. The root samples were collected on every paurṇimā (full moon) and amāvāsyā (new moon) days in śiśira and grīṣṃa ṛtu (as per classics) of the year 2013-14. The physicochemical parameters such as pH, ash values, extractive value, total alkaloid content, total flavonoids content (UV spectrometer with AlCl3 reagent), total phenolic content (Singleton and Rossi method), total carbohydrate content (UV spectroscopy with glucose as standard), UV-VIS-NIR and HPTLC were determined. RESULT: The results of the analytical studies clearly validate the logic of the recommendations of Suśruta and Cakrapāṇi. According to these recommendations, uṣṇa vīrya drugs must be collected during āgneya ṛtu i.e. grīṣṃa ṛtu. In present study, total phenolic, flavonide and carbohydrate content were found more in pournima samples. GAP samples showed maximum differentiation from rest of the samples with regards to TCA, TCW, TFW, MEx, WEX, pH etc. parameters. The Grīṣṃa Jyeṣṭha Paurṇimā (GJP) and Āṣāḍha Paurṇimā (GAP) samples were found to be superior than amāvāsyā samples w.r.t. functional groups and withanoloid content respectively on HPTLC. CONCLUSION: The observations of experimental studies validate the concept of seasonal as well as lunar collection of herb Ashwagandha to yield a drug of superior quality of active principles.