Essential oils from Conamomum rubidum: The phytochemical, microbiological, and molecular docking study

This study explored the interaction of major components in essential oils from aerial parts and rhizomes of Conamomum rubidum (Lamxay & N.S.Ly) Skornick. & A.D. Poulsen (Zingiberaceae) collected in Hongiao National Park (Lamdong province, Vietnam) to the relevant targets of microtubes. Delta-3-Carene (33.14% and 20.15%), beta-phellandrene (14.63% and 25.61%), and 1,8-cineole (17.14 and 3.26%) were three major components in essential oils from aerial parts and rhizome of C. rubidum, respectively. The aerial parts oil possessed fungicidal activity against Candida albicans (MIC = MFC = 0.4%) and rhizome oil bactericidal activity against Staphylococcus aureus (MIC = MBC = 0.8%). A molecular docking study was performed with antimicrobial targets of S. aureus (2W9S, 1HSK, 2ZCQ) and C. albicans (3PVK, 5V5Z, 1IYL). Among the three components, beta-phellandrene has the best affinity to the relevant targets of S. aureus, while Delta-3-care and 1,8-cineole exhibited good binding energy to the targets of C. albicans compared to beta-phellandrene. Along with the in vitro activity test, the docking study demonstrated that beta-phellandrene kept an important role in the ability to inhibit S. aureus. At the same time, Delta-3-carene and 1,8-cineole played a significant part in the capacity to inhibit C. albicans. By the ADMET calculations, Delta-3-carene, beta-phellandrene, and 1,8-cineole can potentially be used as antimicrobial agents.