Antimicrobial activity of different honey samples and their protein estimation

Background: The ancient Medicine showed its versatility in applying various aspects of honey produced naturally. Honey has proved previously been antimicrobial agent as well as showing wound healing property by many authors. However, the properties of honey depend on its type, origin of location and flower which develops the final product. The current work was focused on the antimicrobial activity and protein content of honey originated from two commercial honey and two wild honey obtained from Vachellia nilotica and Tamirindus indica. Methods: All the four honey were collected and an agar well diffusion assay was performed to determine antimicrobial activity against the selected microorganisms viz. Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. Further study was continued with the best results obtained from Vachellia nilotica honey by using minimum inhibitory concentration (MIC) test through spectrophotometric analysis. The protein estimation from honey samples was performed through Lowry method. Results: The agar diffusion assay showed that, Vachellia nilotica honey had greater antimicrobial activity against the bacterial strains compared to the other three honey types. The agar well diffusion method showed that Vachellia nilotica honey has the maximum zone of inhibition against Escherichia coli (24 mm), Staphylococcus aureus (20 mm), Bacillus subtilis (15 mm), and Pseudomonas aeruginosa (15 mm). The MIC test of the same showed that the honey sample has maximum inhibitory concentration at 6.3% for Pseudomonas aeruginosa (21 mm) and 50 % for Staphylococcus aureus (24 mm). The spectrophotometric analysis results for the minimum inhibitory concentration of Vachellia nilotica honey ranged from 0 (0.04%) to 0.19 (6.3%) for Pseudomonas aeruginosa and 0.02 (0.02%) to 0.24 (6.3%) for Staphylococcus aureus. The protein estimation showed that four honey samples have around 50% of protein compared to standard BSA. Conclusion: Vachellia nilotica honey showed maximum antimicrobial activity compared to other three types of honey studied and also possess proteins. This honey can be used in alternative medicine.