Effect of manuka honey on human immunodeficiency virus type 1 reverse transcriptase activity

Manuka honey (MkH), derived from New Zealand manuka tree (Leptospermum scoparium), is considered a therapeutic agent owing to its antibacterial, antioxidant, antifungal, antiviral, anti-inflammatory, and wound healing activities. In this study, the inhibitory effect of five honey types, including MkH, on HIV-1 RT activity was evaluated, using an RT assay colorimetric kit, according to the manufacturer's instructions with slight modifications. MkH exerted the strongest inhibitory effect in a dose-dependent manner, with a half maximal inhibitory concentration (IC₅₀) of approximately 14.8 mg/mL. Moreover, among the MkH constituents, methylglyoxal (MGO) and 2-methoxybenzoic acid (2-MBA) were determined to possess anti-HIV-1 RT activity. MGO and 2-MBA in MkH were identified by High Performance Liquid Chromatography (HPLC) and Liquid Chromatograph - Mass Spectrometry (LC-MS/MS). The findings suggest that the inhibitory effect of MkH on the HIV-1 RT activity is mediated by multiple constituents with different physical and chemical properties.