Phenolic profile, antioxidant properties, and pollen spectra of Iranian-originated honeys

This study was intended to determine the melissopalynological characteristics, LAB color, browning index, total phenolic content, antioxidant activity, phenolic profile, and their correlations within Iranian honeys. Ten honey samples were collected from beekeepers in various floristic regions of Iran, along with two commercial multi-floral samples. To determine the antioxidant activity, three methods of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, β-carotene bleaching, and Ferric reducing/antioxidant power (FRAP) were used. Phenolic compounds were analyzed by high-performance liquid chromatography with diode-array detection (HPLC–DAD). Pollen analysis revealed that bees primarily fed on the Fabaceae and Asteraceae families in the Iranian flora. The local samples were taxonomically categorized as multi-floral honey. Besides, the commercial samples demonstrated the lowest levels of total phenolics and relatively poor antioxidant activity across all three methods. Syringic acid and luteolin were the predominant phenolic compounds in all samples. A strong correlation (p < 0.01) was found between color, melanoidin content and antioxidant activity, while no significant correlation existed between phenolic content and antioxidant activity. Overall, the results confirmed that examined multi-floral honeys exhibited inferior antioxidant activity compared to studies conducted in other regions worldwide, possibly due to sugar-fed bees, insufficient levels of potent phenolic constituents, and post-harvest thermal treatments.