The Antimicrobial Activity and Biochemical Composition of Manuka, Chestnut, Kashmir, Hadramy, Acacia and Blossom Honey Agianst S. Aureus and P. Aeruginosa

Abstract

Antibiotic resistance recently demanded search for alternative antimicrobial compounds, as excessive use of available antibiotics is linked with making the problem worst. Honey's antimicrobial property and activity, which were well known for a long time, has rekindled interest for the therapeutic application of honey in the treatment of bacterial infection. Staphylococcus aureus and Pseudomonas aeruginosa are important clinical pathogens involved in skin and wound infections worldwide. It is therefore imperative to find effective antimicrobial agents against these pathogens. This study was undertaken to assess the antimicrobial activity and composition of a range of honeys including Chestnut, Kashmir, Hadramy, Acacia and Blossom honey. Putative synergistic activity of honey was investigated using antibiotic discs including Ampicillin (AP), Chloramphenicol (C), Penicillin G (PG), Streptomycin (S), Sulphatriad (ST), Tetracycline (T) and Azaleic acid. Manuka honey was used in the study for comparative purposes. The honeys were tested at 75% concentration (w/v) and compared with a sterile Tryptone soy broth (TSB) control solution. The biochemical composition was determined by measuring: polyphenol content by Folin Ciocalteau method, antioxidant capacity by ferric ion reducing power assay, hydrogen peroxide (H2O2) by catalase test, pH and sugar content by pH strips and refractometer, respectively. Using broth culture method, Chestnut, Kashmir and Manuka honey 75% concentration inhibited the growth of both S. aureus and P. aeruginosa at 24 hours (p≤ 0.05). There was no significant difference between the inhibition of both bacteria by Chestnut and Manuka honey (p≥ 0.05). One or more honey increased the zone of inhibition for at least one antibiotic disc (p≤ 0.05). Acacia and Chestnut honey combination with Azaleic acid significantly reduced the growth of both bacteria in broth at 24 hours (p ≤ 0.05). Dark colour honeys were found to contain the highest level of polyphenol and antioxidants. All honeys were acidic with an average pH of 4.5±0.5 SD and all have a high sugar content of more than 75%. Except for Blossom honey, all the honeys tested positive for the production of H2O2. Keywords: Honey, Bacteria, Antimicrobial, Biochemical, Activity, Time