Isolation of Bioactive Compounds in Allanblackia Floribunda Fruit and The Molecular Docking of The Compounds Against SARS-CoV-2 Variants

Abstract

Compounds were isolated from the seed of Allanblackia floribunda using biologically guided chromatographic methods. Garcinia bioflavonoid (GB-1a and GB-2a), microdiplosone, and malic acid were isolated from the seed, pulp, and peel of the fruit. These compounds, even though they are known compounds previously isolated from another member of the Clusiaceae family, have not been isolated from Allanblackia floribunda. The structural elucidation of isolated compounds was done using IR, 1HNMR, 13C NMR, and MS spectroscopy. The molecular docking studies of compounds with SARS-CoV-2 variants (6M0J), omicron 2 (7T9L), and 6LU7 and subsequent comparison with molnupiravir and remdesivir known medications for SARS-CoV-2 showed that GB1a and GB2a had docking scores of -8.3 and -8.6 respectively which was close to that of molnupiravir (-8.3) but greater than that of remdesivir (-7.6). At the same time, that of microdiplodiasone and malic acid were lower than that of the two drugs. Also, GB1a and GB2a had better docking scores when docked with omicron 2 (7T9L) and 6LU7 than the reference ligands. These suggest that the compounds can be investigated further for the development of active drugs against SARS-CoV-2.

Keywords

• Allanblackia floribunda
• Garcinia biflavonoids
• SARS-COV2

References

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