Wound-Healing and Antibacterial Activity of the Quercetin-4-Formyl Phenyl Boronic Acid Complex against Bacterial Pathogens of Diabetic Foot Ulcer.

Complications of diabetic foot can be prevented using a naturally occurring, efficient, and newly synthesized antimicrobial agent. The purpose of the study was to improve wound healing and antibacterial effects of quercetin and its esterified complex with 4-formyl phenyl boronic acid (4FPBA-Q) compared with phenytoin. The formation of the 4FPBA-Q complex was confirmed by thin-layer chromatography (TLC), Fourier transform infrared (FTIR) spectroscopy, and mass spectrometry (MS). The prepared 4FPBA-Q complex was used against Gram-positive bacteria along with Gram-negative bacteria, and more than 2-fold decrease in minimum inhibitory concentrations (MIC) was observed compared to pure quercetin. Scanning electron microscopic images of and showed their complete destruction after incubation with the 4FPBA-Q complex even after 3 h. Interestingly, wound-healing properties of the 4FPBA-Q complex in infected diabetic rats increased from 64 to 99% as compared to phenytoin, which were increased from those of noninfected diabetic rats. Furthermore, histopathological evaluations showed significantly enhanced wound healing, re-epithelialization, fibroblasts, and angiogenesis in wounds of diabetic rats after 10 days. Conclusively, reduction in the primary irritation index (PDII) and improved antibacterial and wound-healing properties render the 4FPBA-Q complex ideal for diabetic foot ulcer treatment.