Analysis of Polyphenol Content and Antioxidant Capacity of Four Varieties of Nigerian Honey

Honey produced in Nigeria from diverse floral sources represents a rich but understudied repository of bioactive polyphenolic compounds with antioxidant and antimicrobial properties. This study analyses the polyphenol content and antioxidant capacity of four varieties of Nigerian honey obtained from Benue, Oyo, Zamfara, and Cross River states, representing different ecological zones and botanical origins. Honey samples were collected directly from registered beekeepers, processed into aqueous extracts, and subjected to biochemical characterization. Total phenolic content was quantified by the Folin-Ciocalteu method, total flavonoid content by the aluminium chloride colorimetric method, and individual polyphenolic compounds were tentatively identified by reversed-phase high-performance liquid chromatography with UV-Vis detection. Antioxidant capacity was determined by DPPH radical scavenging, ABTS decolourization, and the cupric-reducing antioxidant capacity (CUPRAC) assay. Results show significant variation in polyphenol profiles across honey varieties. Benue state honey derived from predominantly savanna flora showed the highest total phenolic content and the strongest DPPH scavenging activity. Oyo honey showed the highest flavonoid content, while Cross River rainforest honey contained the most chemically diverse phenolic profile by HPLC analysis. HPLC identified kaempferol, quercetin, luteolin, and caffeic acid as common polyphenols across multiple varieties. Total phenolic content showed strong positive correlations with all three antioxidant capacity measures. The findings demonstrate that Nigerian honey varieties possess significant antioxidant potential with potential nutraceutical applications. Keywords: honey, polyphenols, antioxidant capacity, HPLC, Nigerian honey varieties.