Effects of Curcuma longa L. and Piper nigrum L. Against Methicillin Resistant Staphylococcus aureus and Infectious Angiogenesis

Abstract

Methicillin drug resistant Staphylococcus aureus is a challenging microbe among bacteria borne infectious diseases and is extremely difficult to treat because of resistive nature of pathogen. Therefore, new agents are always needed to treat MRSA associated infections. Extracts from plants have been in medicinal practice since early ages of mankind. Current research is meant to discern the therapeutic aspects of Piper nigrum L. and Curcuma longa L. as solo or in combinatory medicinal agent against bacterial strains and associated infectious angiogenesis. The individual MICs of Curcuma longa and Piper nigrum calculated by agar well diffusion method were 1.56 mg/mL and 12.5 mg/mL respectively whereas the MIC of the combination of Curcuma longa and Piper nigrum was 0.062 mg/mL, indicating significant decrease in effective MIC in combination. FICI value was 0.034 ≤ 0.5 that confirmed the synergistic antibacterial activity of the combination extract. MTT assay showed that the cell survival percentage and IC50 values of Curcuma longa L., Piper nigrum L. and their combination were 69%, 41%, 80% and 38.3 ± 2.82, 9.92 ± 1.84, 62 ± 5.32 respectively indicating therapeutic doses were non-toxic. Further antibacterial activity of extracts showed promising antibacterial effects against MRSA. Effects on infectious angiogenesis were observed by CAM assay which revealed that when Curcuma longa L. and Piper nigrum L. were used in combination, inhibition of neovascularization was more promising as compared to individual effect which further testified the synergistic effect of Piper nigrum L. Present study accumulatively reports the novel potential utility of Curcuma longa L. and Piper nigrum L. extracts in a synergistic way against MRSA infection by interfering the mechanism of infectious angiogenesis and bactericidal action; suggesting further investigation to isolate active compounds for bactericidal and anti-infectious antiangiogenic activities that may serve as therapeutic agents in the modern field of medicine.