Review on antibacterial activity of Himalayan medicinal plants traditionally used to treat pneumonia and tuberculosis

Objectives The main objective of this review was to collect scattered literature on ethnomedicinal plants used to treat pneumonia and tuberculosis in the Himalayan region and their in-vitro validation against bacterial pathogens. Key findings Current review contains information on ethnomedicines of total 137 plants from Himalaya region. Out of these, 59 plants have been studied in vitro against bacteria while seven plants extracts have been checked for their toxicological effects. The most commonly used plant families for pneumonia and tuberculosis therapy in the study region were Asteraceae, Bignoniaceae and Fabaceae (seven plants in each); of these, Curcuma longa L., Punica granatum L. and Justicia adhatoda L. carried the most inhibiting potential against Staphylococcus aureus and Streptococcus pneumoniae while that of Acalypha indica L. against Mycobacterium tuberculosis. Different compounds such as ascorbic acid, curcumin, vasicine, piperine, quercetin, myricetin and gallic acid being reportedly isolated from these plants possess antibacterial potential. Himalayan region has variety of ethnomedicinal plants used against pneumonia and tuberculosis; however, studies on in-vivo activity, toxicology and mechanism of action are very limited. Hence, detailed investigation on these aspects needs to be carried out for the development of novel antibacterial drugs from the studied plant species.