The use of biomass for the development of environmentally friendly and industrially useful materials is still attracting global interest. Herein, cellulose nanocrystals were prepared from Siam weed. The production steps involved dewaxing the biomass sample, bleaching treatment, alkali treatment and acid hydrolysis. The resulting cellulose nanocrystals were characterized using Fourier transformed infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS) technique. Chemical composition results showed that Siam weed contained 39.6% cellulose, 27.5% hemicellulose, 28.7% lignin and 4.2% extractive. FTIR spectrum confirmed the presence of cellulose and absence of lignin and hemicellulose while XRD analysis revealed that the cellulose nanocrystals have crystallinity index of 66.2% and particle size of 2.2 nm. TGA revealed that thermal stability of raw Siam weed is lower than that of its cellulose nanocrystals due to the presence of the non-cellulosic component with lower temperature of degradation. SEM revealed that degradation of cellulosic chain had occurred. TEM confirmed that the crystal size is in the nanoscale with an average size <100 nm. DLS data revealed a nanocellulose with an average hydrodynamic size of 213 nm and a zeta potential at -9.57 mV.

Background/Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the resistant pathogenic microorganisms that poses a global health threat due to its resistance to β-lactam antibiotics where the protein penicillin-binding protein 2a (PBP2a) plays a crucial role in its resistance. This study explores the potential of phytochemicals from Uvaria chamae, a plant with known medicinal properties, to serve as dual-site inhibitors of PBP2a, targeting both the active and allosteric sites. Methods: Phytochemicals previously identified in U. chamae were subjected to molecular docking and molecular dynamics simulations to evaluate their binding affinities and stability at PBP2a’s active and allosteric sites. The compounds’ pharmacokinetic profiles were predicted in silico using SwissADME tools. Root-mean-square deviation (RMSD), radius of gyration, and binding free energy were analyzed for dynamic stability. Results: Among the evaluated compounds, Uvarinol and Dichamanetin demonstrated high binding affinities compared to the co-crystallized ligand and standard antibiotics like ceftaroline. Uvarinol exhibited the highest binding affinity at both sites, with a docking score of −14.94 kcal/mol and a predicted inhibition constant (Ki) of 0.01 nM. Molecular dynamics simulations further confirmed the robust stability of Uvarinol and Dichamanetin, as indicated by consistently lower RMSD values relative to the co-crystallized ligand. Pharmacokinetic predictions revealed favorable drug-likeness and low toxicity, although Uvarinol showed limited gastrointestinal absorption. Conclusions: Uvarinol and Dichamanetin show promise as dual-site PBP2a inhibitors, offering a novel strategy to combat MRSA resistance. Their structural and pharmacokinetic properties make them viable candidates for further development, though experimental validation and formulation optimization are necessary to overcome bioavailability challenges.