Phytochemical characterization and evaluation of the antibacterial activity of Amruthotharam kwath, a traditional polyherbal formulation on multidrug resistant clinical isolates from the respiratory tract

Abstract

Antibiotic resistance is a multifaceted medical issue affecting the global healthcare sector. Despite continued research and development to combat antibiotic resistance, the development of new antibiotics lags behind the rates of drug resistance. Among the various research strategies under development, traditional polyherbal formulations have greater potential to resolve infectious conditions caused by antibiotic resistant pathogens. Unlike monotherapy antibiotics, polyherbal formulations contain a variety of secondary antibacterial metabolites and their enhanced synergistic action renders them potent therapeutic agents. Multitarget action of phytocompounds at low concentrations poses very low selection pressure that prevents bacteria from developing new resistance mechanism against polyherbals. The study was focused on exploring the antibacterial efficacy of a traditional polyherbal formulation Amruthotharam kwath which had been used to treat respiratory tract infections, one of the leading infectious conditions prevalent in our country. Respiratory tract infection caused by multidrug resistant gram-negative pathogens leads to ineffective empirical treatments and worsens the situation. The study involves preliminary phytochemical analysis, quantification of phytoconstituents, metabolite profiling of the formulation and its antibacterial effect on multidrug resistant clinical isolates from the respiratory tract. The phytochemical analysis revealed the presence of various classes of phytocompounds with antibacterial activity. Antimicrobial assays reported promising antibacterial effect. MIC values were found to be in the range of 6.25 mg/mL-12.5 mg/mL and its MBC ranges from 6.25 mg/mL-128 mg/mL. The formulation exhibited bactericidal effect on majority of the isolates.LC-MS/QToF revealed the presence of 76 secondary metabolites, majority of which possessed antibacterial activity. The SEM image analysis confirmed complete destruction of cell wall as well as cell membrane of the pathogens. This study suggests the promising herbal therapy of Amruthotharam kwath which can be proposed as an alternative for treating infections caused by multidrug resistant pathogens.