Study of effect of betel leaves (Piper Betel) on β-lactamase producing pathogens

The increasing resistance to antimicrobials among pathogens demands new strategies for management of infectious diseases. In this respect, use of combination therapy and/or use of herbal compounds are more likely to result in successful therapeutic outcomes. In the current study, solvent extracts of Piper betel leaves were tested for antibacterial activity against pathogenic β-Lactamase producing strains as well as common laboratory cultures. The bioactive compounds from betel leaves were extracted with the help of Soxhlet apparatus at 60°C to obtain a semi-solid mass using different solvents such as ethanol, methanol, acetone and water. The antibacterial activity of solvent extracts of P. betel leaves was evidently confirmed by the observed zones of inhibition in the range of 11-26mm. The Minimum bactericidal concentration of methanol extract of P. betel leaves was also determined and it was found to be 10mg/ml. Moreover, the sub-inhibitory concentrations of methanol extracts of P. betel leaves successfully lowered the MBC of ampicillin from 10mg/mL to 300µg/ml, indicating a synergistic activity. Furthermore, they also showed a moderate anti-oxidant property suggested by the calculated DPPH scavenging activity. In addition, the GC-MS analysis of methanol extract of P. betel leaves was carried out and it showed the presence of various bioactive compounds including benzoic acid, pyrazine, coumaran and 4-vinyl-gluacol. These results suggest the potential of P. betel leaves as a source of remedy towards the problem of antimicrobial resistance.