No abstract

The antioxidant properties of natural honey primarily rely on the floral origin from which nectar is collected by bees. Thus, the current activity evaluated the antioxidant properties of honey based on its floral type. The honey floral origin was verified by the melissopalynological technique. Antioxidant properties were determined by using standard procedures and analyzed by SAS. Six unifloral honey types with their harvesting month were identified. Accordingly, Guizotia (74% of pollen frequency), Coffea arabica (68%), Vernonia (90%), Croton macrostachyus (64%), Schefflera abyssinica (100%), and Eucalyptus (100%) were cropped in November, February, February, May, April, and June separately. Statistically, a variation ( p < 0.05 ) in antioxidant parameters was displayed between unifloral honeys. Vernonia honey exhibited the maximum total phenol ( 77.2 ± 0.7 ), total flavonoid ( 65.0 ± 3.8 ), and total antioxidant content ( 65.4 ± 0.3 ). On the other hand, S. abyssinica honey recorded the least total phenol content ( 24.1 ± 0.4 ), total flavonoid content ( 18.6 ± 2.7 ), and total antioxidant content ( 5.6 ± 0.5 ). Statistical analysis showed a positive correlation between all the tested antioxidant parameters. Thus, the current study indicated that all the tested Ethiopian unifloral honey had good sources of antioxidants with the most Vernonia honey followed by C. macrostachyus whereas S. abyssinica honey had the least followed by Eucalyptus.

Beekeeping has significantly contributed to environmental conservation and the preservation of natural resources. Although the quality and quantity of flora available play a major role in the success of the sector, the botanical makeup of natural vegetation varies greatly. This study was conducted targeting the identification and documentation of major honeybee floras and their flowering calendar. Midland and lowland agroecologies were purposively selected. Continuous field plant registration was performed. Melissopalynological analysis from bee pollen and honey were used to identify floral origin. Field observations identified 59 and 63 plants in the midland and lowlands, respectively. Season 1 had the highest pollen yields, ranging from 11051.8 ± 56.4 g (midlands) to 878.3 ± 18.3 g (lowlands), while season 4 ranged from 16.8 ± 6.3 g (midlands) to 15.6 ± 7.4 g (lowlands) and had the lowest pollen yield. In both regions, February, March, July, and August are the months when pollen is not brought into the hive and could be used as starvation periods. A total of 1430.8 ± 75.4 and 1291.8 ± 71.4 g of bee pollen/hive were collected throughout the year in midland and lowland, respectively, and Asteraceae was the richest family accounting around 90% of pollen weight. In both agroecologies, honey is harvested three times a year. In the midland, monofloral honey, namely, Guizotia spp (64.42%) and Croton macrostychus (47.42%), was harvested in November and May, respectively, while honey harvested in February was multifloral type. Similarly, in the lowlands, monofloral honey of Guizotia spp (51.85%), Coffee arabica (55.22%), and Croton macrostychus (50.42%) was harvested in December, March, and June, respectively. Based on the results, Bidens prestinaria, Bidens pilosa, Guizotia spp, C. macrostachyus, Eucalyptus spp, Lepidium sativum, Zea mays, Hypostes trifolia, Vernonia spp, Trifolium spp, Helianthus annuus, C. arabica, Brassica abyssinica, Andropogon abyssinicus, Sorghum bicolor, Cordia africana, Syzygium guineense, and Terminalia spp are major bee plants. It is found that the study area is rich in bee plant diversity and hence has a potential for honey production.

Background Honey is a natural sweetener and viscous food which is synthesized from the nectar of flowering plants by bees. As a worldwide, it has been traditionally used for incurring different diseases. However, In recent times, the emergence of multi and extended drug-resistant human pathogens called for an urgent search for more effective sources of natural products to treat infectious diseases. The biological activity of honey primarily relies on its botanical and entomological origin. Hence, the objective of this study was to screen the in vitro antibacterial activity of honey based on botanical origin produced in Ethiopia. Methods Botanical origin was identified by the Melisopalynological analysis method. The inhibition zone was determined by agar well diffusion assay. Minimum inhibitory concentration was done by broth diffusion. Result Six different monofloral honey namely: Guizotia (75.3% pollen grain counted), Coffee arabica (68.6%), Vernonia (90.5%), Schefflera abyssinica (100%), Croton macrostachyus (64.4%) and Eucalyptus (100%) honey was harvested through December, February, February, April, May, and June respectively from the study area. All the monofloral honey inhibited the growth of all the bacterial strains even though the diameter of the inhibition zone varied. C. macrostachyus, Vernonia, Guizotia, and C. arabica were comparatively more whilst S. abyssinica was the least effective against all the tested bacterial strains. The grand mean inhibition zone ranged from 17.0 ± 1 mm by C. macrostachyus to 10.5 ± 1 mm by S. abyssinica against all the bacterial strains. Besides, the MIC of botanical honey type ranged from 11.7 ± 3.3% w/v by C. macrostachyus against S. aureus to 37.5 ± 1% w/v by S. abyssinica against P. aeruginosa. Conclusion The current result indicated that there is a disparity in antibacterial properties between monofloral honey. The more effective honey against the tested bacterial strain were those produced from the nectar of Ethiopian medicinal plants; based on literatures. Therefore, further in-vivo and in-vitro research would be expected from the concerned researchers on the association between the biological compounds present in each part of medicinal plants and honey samples.