Study of the Antimicrobial Potential of Consortiums of Hot Alcoholic Extract of Plants against Multidrug Resistant Bacteria Including One Vancomycin-Resistant Staphylococcus aureus (VRSA)

Abstract

Increasing antibiotic resistance exerts threatening implications in human health care. It subsequently increases the need to develop an alternative strategy to counter the growing concern against the superbug infection in open wounds. In the present study, two combinations of herbal alcoholic extracts have been assessed for antimicrobial activity against the isolates collected from human burn wound sample and biopsies. Total of 42 strains have been isolated and screened for its antibiotic resistance. It was found that a significant amount of bacteria adapted resistance to traditional antibiotics such as Gentamycin and Imipenem. Out of the 42 isolates, 28 isolates were found to be broad-spectrum antibiotic resistant strains. The study demonstrated the inhibition of resistant strain of Vancomycin-resistant Staphylococcus aureus (VRSA) by hot alcoholic extract of the combination of Azadirachta indica bark, Vitex negundo leaves, Eucalyptus globules leaves, Piper betel leaves and Ficus religiosa bark (N3PB) extract while multidrug resistant Escherichia was inhibited by consortium of Ocimum tenuiflorum leaves, Ficus religiosa bark and Piper betel leaves (TPB) extract. Chloramphenicol, Kanamycin and Tetracycline effectively inhibited all 7 Gram-positive bacteria. Kill time study indicated that N3PB extract inhibited Enterobacter spp. and Pseudomonas spp. inhibited within 0 h of contact time. But TPB extract showed relatively high contact time for efficient bioactivity. Moreover, both of extracts showed no anticancer activity in range of 10 to 80 μg/ml against SK-MEL-2 cell line, indicates extract selectively inhibited bacteria.
Keywords: Azadirachta indica, Ocimum tenuiflorum, antibiotic resistance, kill time study, antimicrobial activity, cytotoxicity