Physio-Chemical properties, Microbial safety and Anti microbial Activities of Honey Collected from Kuyu Woreda , North Shewa ,Ethiopia

Abstract

Honey is a natural sweetener with various beneficial properties including anti-oxidant, nutritional, antimicrobial and industrial application. Among the traditional application of honey is its common role in wound healing as it has antibacterial activity. However, there are no data on the microbial quality and the significance of honey in traditional healing of infectious diseases in the study area. To this effect, this study was designed to document the physico-chemical properties, microbial quality and antimicrobial activities of honey samples collected from North Shewa, Kuyu woreda, Garba Guracha Town. Standard microbiological methods were followed for microbiological analysis. The disc diffusion assay method was implemented for antimicrobial activity tests, while the heavy metal content analysis was carried out using Flame Atomic Absorption Spectrophotometer. Other physicochemical parameters including pH and moisture content were also determined. Socio-demographic data related to the traditional use, storage, harvest, and others practices were gathered using structured questionnaire. Result of the current study indicated that the honey samples had mean pH, % ash and moisture contents of 4.10.13, 0.84% 021%, and 16.78%1.37%, respectively. Furthermore, mean zinc and lead contents of the honey samples were 0.45 0.06 mg/l and 0.08 0.04 mg/l, respectively. Microbiologically, Salmonella sp, Shigella spp, Lactic acid bacteria, and Enterobacteriaceae were not detected in all studied honey samples. Only aerobic mesophilic bacteria, yeasts and molds were encountered in the samples with variable counts among the groups. The number of Aerobic mesophilic bacteria (AMB) varied between 3.94 Log cfu/ml -5.95 log CFU/ml with mean count of 5.00  0.55 log cfu/ml. The number of yeasts and moulds were usually below detectable level with mean counts of 1.87 0.32log cfu/ml and 1.16 0.21Log cfu/ml, respectively. Antimicrobial activity of honey revealed some degree of activity only to gram negative bacteria (Escherichia coli and S. typhimurium) but no effect on Staphylococcus aureus using honey concentration up to 50%. The inhibition zone observed for S. typhimurium using honey concentration of 50% and 10% were 16.110.70mm and 9.03 0.94mm, respectively. Likewise, the Inhibition zone diameters recorded for Escherichia coli using concentration of 50% and 10% were 13.602.1 and 8.080.64, respectively. These findings provide supportive evidence of the application of honey for the treatment of infectious diseases besides indication of the low level of contamination of honey at the study area with respect to Salmonella and Shigella. This does not, however ensure guaranty for microbial safety of honey since aerobic mesophilic bacteria, yeasts and molds were detected at lower level. Thus, it calls for better storage, preservation, and use of honey for nutritional and medicinal applications.