A theoretical study on inhibitability of silver(I) N-heterocyclic carbene and dimer silver(I) N-heterocyclic carbene complexes against Phytophthora capsici and Fusarium sporotrichioides in Piper nigrum L.

Piper nigrum L. (black pepper) is highly susceptible to many infectious diseases, especially foot rot caused by Phytophthora capsici and yellow disease caused by Fusarium sporotrichioides. The inhibitability of silver-carbene Ag-NHC and di-silver-carbene Di-Ag-NHC complexes on protein 6KD3 in Phytophthora capsici and protein 1JFA in Fusarium sporotrichioides was theoretically investigated using molecular docking simulation. The results reveal that both Ag-NHC and Di-Ag-NHC performing strong inhibitory effects towards both proteins. Docking score energy values regarding [Ag-NHC]-6KD3 and [Di-Ag-NHC]-6KD3 are -11.2 and -11.7 kcal.mol(-1). The corresponding figures for [Ag-NHC]-1JFA and [Di-Ag-NHC]-1JFA are -11.1 and -13.4 kcal.mol(-1). Also, analysis on hydrogen bonding, interaction distance, and van der Waals interactions formed in the inhibitory systems indicates good site-site binding between amino acids of the targeted proteins and the carbene molecules. This study introduces Ag-NHC and Di-Ag-NHC complexes as potential candidates for prevention of infection caused by Phytophthora capsici and Fusarium sporotrichioides, thus mitigate the impacts on the production of black pepper.