Piper lolot is a species of herb used as a popular food in Vietnam. Furthermore, the species has been used as a Vietnamese traditional medicine to treat many diseases. Chemical constituents in the essential oil from leaves of Piper lolot were determined using GC/MS analysis. The anti-gout and anti-diabetic activities of the essential oil were determined through the inhibitory assays against xanthine oxidase, α-glucosidase and α-amylase enzymes. In addition, molecular docking simulations were used to elucidate the inhibitory mechanism between the main compounds and the enzymes. The dominant constituents of the Piper lolot essential oils were determined as β-caryophyllene (20.6%), β-bisabolene (11.6%), β-selinene (8.4%), β-elemene (7.7%), trans-muurola-4(14),5-diene (7.4%), and (E)-β-ocimene (6.7%). The essential oil displayed xanthine oxidase, α-amylase, and α-glucosidase inhibitory activities with IC₅₀ values of 28.4, 130.6, and 59.1 μg/mL, respectively. The anti-gout and anti-diabetic activities of the essential oil from the P. lolot species are reported for the first time. Furthermore, molecular docking simulation was consistent to in vitro experiments. The present study provides initial evidence that the essential oil of P. lolot may be a potential natural source to develop new diabetes preparations.

Herein, a novel fluorescent sensor has been developed for the detection of biothiols based on theoretical calculations of the stability constant of the complex between a Cu²⁺ ion and (E)-3-((2-(benzo[d]thiazol-2-yl)hydrazono)methyl)-7-(diethylamino) coumarin (BDC) as a fluorescent ligand. In this study, on the basis of density functional theory method, the Gibbs free energy of ligand-exchange reaction and the solvation model were carried out using thermodynamic cycles. The obtained results are in good agreement with the experimental data. The BDC–Cu²⁺ complex can be used as a fluorescent sensor for the detection of biothiols in the presence of non-thiol containing amino acids, with a detection limit for cysteine at 0.3 μM. Moreover, theoretical calculations of excited states were used to elucidate variations in the fluorescence properties. The computed results show that the excited doublet states D₂ and D₁ are dark doublet states, which quench the fluorescence of the complex.

Background: Staphylococcus aureus is a nosocomial pathogen responsible for many serious infectious diseases in humans. Finding the anti- S. aureus agents is a time-consuming and costly process. Recently, computational methods have provided a better understanding of the interactions between herbal medicine drug targets to help clinical practitioners rationally design herbal formulae. Methods: In this study, molecular docking simulation was applied to screen a list of natural secondary metabolites from Ganoderma sp. on the protein target S. aureus sortase A. Molecular dynamics models were used to assess the stability of protein–ligand complexes during the first 100 ns. To validate the computational results, 2 Ganoderma species, G. multiplicatum VNKKK1901 and G. sinense VNKKK1902, were tested for antibacterial activity against S. aureus using the disk diffusion method. Results: The results showed that, among the selected compounds, ganosinensin B and ganosinoside A generated the highest binding energy on S. aureus sortase A, and demonstrated strong and stable binding capacity to proteins. In addition, the extracts of G. sinense VNKKK1902 and G. multiplicatum VNKKK1901 were bactericidal, with minimum bactericidal concentration (MBC)/minimum inhibitory concentration (MIC) ratios of 2. Conclusion: Our findings provide the first scientific report on the antibacterial activity of Ganoderma sp., which contain 2 promising compounds, ganosinensin B and ganosinoside A, as potential hits for developing novel drugs capable of supporting treatment of S. aureus infection.

Two styryl-lactone derivatives (1 and 2) were isolated from the aerial parts ofGoniothalamus elegans.

The coronavirus outbreak of 2019 (COVID‐19) has been seen as a global health concern. The 3‐chymotrpsin‐like protease or SARS‐CoV‐2 main protease, whose ability to control the coronavirus replication, has been a promising target for developing drugs against coronavirus infection. In this study, we used the molecular docking approach to screen natural compounds from traditional medicinal plants in Vietnam to find the possible inhibitors of SARS‐CoV‐2 main protease. The docking results revealed that among 170 compounds, the top 15 compounds with the high binding affinity to 3CL protease (PDB ID: 6WNP) might act as promising anti‐SARS‐CoV‐2 molecules. Among these compounds, Gracillin and Proanthocyanidins showed the highest binding affinity with a docking score of ‐9.2 Kcal/mol. However, further experiments are required for developing possible natural therapeutic medications for combating this coronavirus.