Chebulinic acid

Terminalia chebula is a widely used medicinal herb in traditional phytotherapy, valued for its extensive range of therapeutic uses. In this study, the seed extract (TCS) was investigated for its potential against multidrug-resistant (MDR) pathogens associated with diabetic foot ulcer (DFU) infections. The clinical isolate Pseudomonas aeruginosa (DW07) was extremely resistant to standard antibiotics, reaffirming its MDR phenotype. Chemical profiling of TCS with liquid chromatography showed a dense phytochemical profile containing ellagic acid, chebulagic acid, punicalagin, corilagin, and chebulinic acid, which is all attributed to specific anti-pathogenic activities like quorum sensing inhibition, biofilm inhibition, efflux pump obstruction, and disrupting bacterial adhesion. The extract showed dose-dependent antibacterial activity with a minimum inhibitory concentration of 0.70 ppm, and was found to greatly inhibit biofilm formation to the extent of 87.57 %. Transcriptomic analysis also showed wide modulation of bacterial physiology as 54 genes were differentially expressed and significant downregulation of virulence-related proteins such as short-chain dehydrogenase oxidoreductase, histidine kinase, and PtxR. Gene Ontology classification identified functional effects on DNA binding, lipopolysaccharide biosynthesis, and major metabolic pathways. Overall, these findings indicate that the phytochemical variability of T. chebula seeds not only establishes a molecular foundation for its traditional application but also attests to its potential as a plant-based therapeutic approach in the phytomedical management of chronic wound infections due to MDR pathogens.

Ultraviolet-B (UVB) radiation induces significant skin damage by penetrating into the dermal layer, leading to reactive oxygen species (ROS) generation and triggering cellular necrosis and apoptosis. Conventional sunscreens focus primarily on UVB blocking but are limited in their ability to repair dermal damage due to insufficient permeability. In this study, we discover that chebulinic acid (CA), one of the principal monomers in Terminalia chebula Retz., has superior efficacy in promoting recovery from UVB-induced skin damage compared with other major monomers. Mechanistically, CA's anti-UVB function involves regulating the expression of IL-6 and IFN-β through activation of the MAPK pathway. To overcome the formidable barrier posed by the skin, we identify mulberry exosome-like nanoparticles (MELNs) as an efficient transdermal delivery system and develop CA@MELNs loaded with CA. Furthermore, we demonstrate that the dissociative CA within the CA@MELNs delivery system significantly enhances both transdermal penetration and anti-UVB efficiency in vitro and in vivo. Our findings suggest the substantial potential of CA as an effective ingredient and CA@MELNs as a robust and accessible platform for mitigating UVB damage.