In Vitro and In Silico Antimicrobial Activity against Methicillin-Resistant Staphylococcus aureus of Essential Oils from Four Medicinal Plants in Xuan Thuy Mangrove Forest

Abstract

Sphagneticola trilobata, Vitex rotundifolia, Vitex trifolia, and Annona glabra are medicinal plants found in Xuan Thuy mangrove forest that contain essential oils (EOs) and the potential to treat infections. The obtained yields of hydrodistillation essential oil from aerial parts and leaves ranged from 0.01% to 0.12% (v/w) on a fresh-weight basis. Subsequently, in vitro assessments indicated that the EOs of A. glabra, S. trilobata, and V. trifolia displayed antibacterial effects against methicillinresistant Staphylococcus aureus (MRSA), with S. trilobata exhibiting bactericidal effects at minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.2% EO, and A. glabra exhibiting bacteriostatic effects with both MIC and MBC values of 0.8% EO. However, the EO of V. rotundifolia showed no inhibitory effects against S. aureus, even at concentrations of up to 0.8% EO. Furthermore, docking results showed that six compounds exhibited particularly high binding energies (< -7 kcal/mol): α-phellandrene, β-caryophyllene, β-guaiene, alloaromadendrene, bicyclosesquiphellandrene, and bicyclogermacrene. Among these, α-phellandrene, β-caryophyllene, bicyclosesquiphellandrene, and bicyclogermacrene are the main components in the S. trilobata EO; β-caryophyllene, β-guaiene, and alloaromadendrene are the main components in the A. glabra EO; and β-caryophyllene and alloaromadendrene are the main components in the V. trifolia EO. These findings highlight the antibacterial potential of EOs from mangrove plants; therefore, expanded investigations into EOs and the biological properties of mangrove plants may be a promising strategy for combating antimicrobial resistance.