Phytochemical screening, gas chromatograph/mass spectrometer (GCMS) analysis and molecular toxicological potential of Hunteria umbellata aqueous fruit extract against Staphylococcus aureus in accessory gene regulators (AGRs)

Fruits of Hunteria umbellata (HU) have been utilized in folk medicine as potent against Staphylococcus aureus (SA) infections, particularly skin and nasal related conditions. However, there is scarcity of literature concerning toxicological evaluation of graded doses of HU fruit, especially at molecular level, specifically targeting the accessory gene regulator (AGR) system to prevent abuse of doses in the treatment of bacterial infections. This research evaluated molecular toxicological property of SA exposed to varied concentrations of aqueous HU fruit extract ranging from 500 to 3.90625 µg/µL using broth microdilution method and quantification of AGR I and II genes’ expression employing two-step reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). We first identified quality and quantity of chemical compounds in aqueous fruit of HU using phytochemistry and hybrid gas chromatograph–mass spectrometer (GC–MS) technique. Additionally, preliminary bactericidal potential of HU was assessed before molecular toxicology. Results revealed six phytochemicals and twenty analytical grade compounds from a standard library were identified from chromatograms of HU fruit extract. Some main compounds detected are n-Hexadecanoic acid (25.24