STUDIES ON ANTI-MICROBIAL POTENTIAL OF Withania somnifera (L.) DUNAL AND FUTURE PERSPECTIVES: AN OVERVIEW

Withania somnifera is a herb of immense ethnopharmacological importance in Ayurvedic, Siddha and Unani systems of medicine. Due to its immense therapeutic potential and being an important source of novel withanolides, it has been a subject of immense intrigue among researchers. Apart from its anti-inflammatory, antitumor, anti-stress, antioxidant, immunomodulatory, antidiabetic, sedative and hemopoetic properties, there is mounting evidence for its antimicrobial and antiviral properties too. Various withanolides and steroidal lactones isolated so far are known to have high therapeutic value, but works pertaining to their antimicrobial potential have largely been at the synergistic level. No single withanolide has been characterized as a sole antimicrobial and thus, work in this regard is still in the stage of infancy, except for withanone which has recently shown in silico activity against SARS-COV-2. This review summarizes the elaborate antibacterial, antifungal, antiprotozoal and anti-viral work that has been done so far and casts focus on the limitations, in terms of mechanistic aspects of each.