Potential antibacterial, antioxidant and anticancer activities of Nigerian mountain honey in relation to its bacterial flora

Numerous studies have investigated the biological activities of honey, emphasizing its antimicrobial, antioxidant, and therapeutic properties. However, a comprehensive examination of the bacteria isolated from honey has been largely overlooked. This study aimed to bridge that gap by exploring the relationship between the bioactivities of honey and the bacterial spores it contains. Furthermore, there is no comparison between the polysaccharides in honey such as levan and its inherent bacteria. Accordingly, various enzymes, including levansucrase, invertase, glucose oxidase, amylase, and catalase, were assessed in Nigerian mountain honey and their inherent seven bacterial isolates. Honey and its isolates showed levansucrase production to various degrees where the highest activity was obtained with isolate NO.4 and the honey recorded (21U/ml). Additionally, honey and its isolates showed varied activities between (171–465 U/ml), (88–250 U/ml) for amylase and glucose oxidase respectively. The highest catalase activity was recorded by isolate No 4 based on the qualitative test. Interestingly, all isolates lacked protease activity. Honey and specific isolates inhibited various pathogenic bacteria, including Salmonella enterica Typhi, Escherichia coli, and Bacillus cereus. Also, fungi such as Candida albicans. In addition, honey and its isolates had high antioxidant activities ranging from 58 to 77%. The polysaccharides Lev1, Lev2, and honey have no cytotoxic effects on normal cells. They were identified as levans based on FTIR and NMR. Honey and lev1, lev2 showed cytotoxicity against HCT116 cell lines (61.5, 59.5, and 53.70%), respectively. Interestingly, the study found a strong link between the biological activities of the bacteria and the honey itself.