Campesterol Semi-Synthetic Derivatives as Potential Antibacterial: in†vitro and in silico Evaluation.

In this study, twelve campesterol derivatives (2-13) were prepared by esterification reaction at the hydroxy group in C-3 and catalytic hydrogenation at the carbon-carbon double bond in C-5(6). All obtained compounds were characterized by IR, 1 H-NMR, 13 C-NMR, and MS spectra. Campesterol (1) and its derivatives (2-13) were evaluated in vitro against Staphylococcus aureus (ATCC 6538), Streptococcus mutans (ATCC 0046), Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), and Klebsiella pneumoniae (ATCC 10031) using the microdilution method. Among tested compounds, 4, 6, 9, 11, 12, and 13 displayed the best antibacterial activity. Moreover, to support the antibacterial activity experiments, the investigation of molecular interactions of more active compounds, and also compound 1 and neomycin, used as starting material and positive control, respectively, at the binding site of the target proteins was performed using molecular docking simulations. Four compounds (7, 9, 10 and 11) are herein described for the first time.

Unraveling the antifungal composition of bitter orange decoction against the melon pathogen Fusarium jinanense.

Bitter orange (Citrus aurantium) is an important source of essential oils with high antimicrobial activities, however the composition and antifungal potential of the decoction peels is little explored. This study assessed the peel decoction's chemical profile at the secondary metabolism level and its antifungal activity against the melon phytopathogen Fusarium jinanense. The decoction's antifungal potential was investigated using a bioassay-guided fractionation approach based on Solid-Phase Extraction (SPE) and LC-HRMS/MS analysis. Coumarins and flavones were the most abundant classes of compounds in the high-value fractions responsible for up to 61% of the mycelial inhibition of F. jinanense. Overall, this study has presented for the first time the chemical composition, the antifungal potential of the decoction of C. aurantium peels and the compounds associated with these results. This strategy can guide the exploration of under-explored food sources and add value to compounds or fractions enriched with bioactive compounds.