Antioxidant and antibacterial properties of stingless bee (Meliponula spp.) honey from the northern highlands of Tanzania, in comparison with Apis mellifera honey

Abstract

Meliponiculture is an emerging practice in Africa where beekeeping is dominated with the management of the honey bees, Apis mellifera. Nevertheless, communities in the northern highlands of Tanzania have a long history of managing stingless bees for their honey which has putative medicinal value. The current study aimed to evaluate the antioxidant and antibacterial properties of honey samples from two stingless bee species, namely Meliponula (Axestotrigona) ferruginea and Meliponula (Axestotrigona) togoensis, in comparison with A. mellifera honey. Physicochemical properties were also determined to assess the quality of the studied honey samples. The honey samples conformed with the regional quality standards for moisture content, free acidity and HMF for both stingless bee and A. mellifera honey. Stingless bee honey exhibited stronger antioxidant potency, displaying higher mean values of total flavonoid (54.12 – 56.40 mg QE/100 g) and phenolic compounds (81.92 – 87.56 mg GAE/100 g), DPPH radical scavenging activity (65.81 – 68.40%) and ferric reducing antioxidant power (109.78 – 126.64 µmol Fe (II)/100 g) compared to A. mellifera honey (33.17 mg QE/100 g, 61.13 mg GAE/100 g, 41.44%, 65.00 µmol Fe (II)/100 g, respectively). Additionally, stingless bee honey demonstrated higher inhibitory effect against Staphylococcus aureus, Bacillus subtilis and Salmonella typhi, with minimum inhibitory concentrations ranging from 0.16 – 5% v/v, compared to 2.5 – 20% v/v for A. mellifera honey. These findings highlight the distinct bioactive properties of stingless bee honey and validate its applications in traditional therapy. More studies are encouraged to elucidate specific bioactive ingredients in stingless bee honey to further substantiate its medicinal potency.