Screening of Selected Stingless Bee Honey Varieties for ACE2-Spike Protein-Binding Inhibition Activity: A Potential Preventive Medicine Against SARS-Cov-2 Infection

The broader objective of this study is to identify natural materials that might inhibit the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We have focused on stingless bee honey, which has a unique taste that is both sweet and sour and sometimes bitter. We screened 12 samples of honey from 11 species of stingless bees using an angiotensin-converting enzyme 2 (ACE2)-spike protein-binding assay and phytochemical analysis. Ten of the samples showed inhibition above 50% in this assay system. Most of the honey contained tannins, alkaloids, flavonoids, triterpenoids, carotenoids and carbohydrates. Our findings in this in vitro study showed that honey from stingless bees may have a potent effect against SARS-CoV-2 infection by inhibiting the ACE2-spike protein-binding.