In vitro antimicrobial efficacy of some plant extracts against multi-drug resistant Staphylococcus aureus and Streptococcus pyogenes isolated from buffalo mastitic milk

The conventional drugs used for the treatment of buffalo mastitis are losing their efficacy day by day due to increasing resistance in microbial organisms. It is therefore people nowadays are going back to use old but still quite potential remedy methods by using different herbs and shrubs for the treatment of different animal diseases including mastitis. In current investigation, three botanical extracts viz., garlic (Allium sativum L.), ginger (Zingiber officinale) and red chilies (Capsicum annuum L.) were evaluated individually and concomitantly (with ratio of 1:1) against the multidrug resistant Staphylococcus aureus and Streptococcus pyogenes isolated from buffalo mastitis. Agar well diffusion assay exhibited that red chili shown significantly (P LT 0.05) higher effects than garlic followed by ginger. All concentrations of red chili and 100 percent concentration of garlic exhibited a significantly (P LT 0.05) higher inhibitory effect against Strep. pyogenes comparing with other extracts and reference antibiotic oxacillin and streptomycin. Red chili as well as garlic in 75 and 100 percent concentrations also significantly (P LT 0.05) inhibited the Staph. aureus isolates comparing with ginger and reference drug. Red chili exhibited the highest inhibitory effects when combined with garlic than ginger. Garlic + red chilies showed a significantly (P LT 0.05) higher inhibitory effect against Staph. aureus and Strep. pyogenes as compared to other combined treatments and reference drug. Red chili as well as garlic also showed significantly (P LT 0.05) lower MIC (0.394 and 0.399 mg/ml respectively) against multidrug resistant Strep. pyogenes as compared to the ginger (0.564 mg/ml) and reference antibiotic oxacillin (0.460 mg/ml). Red chilies also showed significantly (P LT 0.05) lower (0.211 mg/ml) MIC against multidrug resistant Staph. aureus as compared to the garlic (0.391 mg/ml), ginger (0.394 mg/ml) and reference antibiotic tetracycline (0.370 mg/ml). Treatment combination based on red chili, garlic and ginger also exhibited significantly (P LT 0.05) lower MIC value against Staph. aureus and Strep. pyogenes as compared to ginger + garlic and reference antibiotic. This study concludes that red chili ranked 1st, garlic ranked 2nd and ginger ranked 3rd for antibacterial activity against multidrug resistant Staph. aureus and Strep. pyogenes. Treatment combination based on garlic + red chili ranked 1st, ginger + red chilies ranked 2nd and ginger + garlic ranked 3rd for antibacterial activity against multidrug resistant bacteria isolates.