Tamarindus indica Leaf Extract Mediated Au NPs for Antimicrobial Treatment of Infectious Skin Wounds in Postoperative Wound Care Applications

Abstract

The main cause of delay in the wound healing process is usually the infection due to pathogens such as Pseudomonas aeruginosais. The current study reports the green fabrication of gold nanoparticles (Au NPs) using Tamarindus indica leaf extract. The prepared Au NPs have displayed significant antimicrobial activities. Also, Au NPs activity alone and when combined with tetracycline was studied on the inoculated wounds with P. aeruginosain in mice. A total of 20 mice were anesthetized and deep skin wounds were made on the back of all the mice. Then, a suspension containing bacteria was applied to wounds. The wound infection was studied by measuring the total microbial count as well as monitoring the wound healing macroscopically. Treatments were performed to all the groups on the wound bed topically using Au NPs alone, Au NPs with tetracycline (Au NPs + tetracycline), tetracycline alone and normal saline in the control group. The Au NPs + Tetracycline group has attained 100% closure of the wound on the 9th day. The wound contraction percentage of animals treated with Au NPs (98%) was noticed to be almost similar with the percentages of normal saline (79%) and tetracycline (99%) animal groups. In addition, all the groups treated with Au NPs + Tetracycline, tetracycline alone and Au NPs alone showed decreased bacterial concentration on the wound surface by the 9th day in comparison to the control group. Similarly, a significant decrease (P < 0.001) was observed in the bacterial count of the groups treated with Au NPs+Tetracycline, tetracycline and Au NPs on comparison with the control group at all the time periods. Treatment with Au NPs + Tetracycline is highly effective than tetracycline and Au NPs alone for the reduction of bacterial load with an increase in the wound macroscopic closure. Therefore, the above results support the application of Au NPs combined with an antimicrobial medicine for treating the skin wound infections.