Preparation and antimicrobial properties of LL‐37 peptide immobilized lignin/caprolactone polymer film

Abstract

The use of biopolymers has gained priority in tissue engineering and biotechnology, both as dressing material and for enhancing treatment efficiency. There is a demand for new biopolymers designed with protease inhibitors and antimicrobials. LL‐37 is an important antimicrobial peptide in human skin and exhibits a broad spectrum of antimicrobial activity against bacteria, fungi, and viral pathogens. Using lignin which is an abundant carbohydrate polymer in nature and a polyacrylic acid, we prepared a lignin/caprolactone biodegradable film by plastifying caprolactone and polyacyrlic acid. Lignin/caprolactone biodegradable film was activated with CDI and then immobilized LL‐37 peptide. The structure was elucidated in terms of its functional groups by attenuated total reflectance‐fourier transform infrared spectroscopy (ATR‐FTIR), and the morphology of the lignin/caprolactone biodegradable film was characterized by scanning electron microscopy (SEM) before and after the immobilization process. The amount of LL‐37 immobilized was determined by ELISA method. It was found that 97% of LL‐37 peptide was successfully immobilized onto the lignin/caprolactone biodegradable film. Antimicrobial activity was determined in the lignin/caprolactone biodegradable film samples by quantitative antimicrobial activity method. According to the results, LL‐37 immobilized lignin/caprolactone biodegradable film samples were effective on test organisms; Gram‐positive Staphylococcus aureus and Gram‐negative Escherichia coli. In bio‐compatibility assays, the ability to support tissue cell integration was detected by using 3 T3 mouse fibroblasts. Samples were examined under transverse microscope, non‐immobilized sample showed a huge cellular death, whereas LL‐37 immobilized lignin/caprolactone biodegradable film had identical cellular growth with the control group. This dual functional lignin/caprolactone biodegradable film with enhanced antibacterial properties and increased tissue cell compatibility may be used to design new materials for various types of biological applications.

Cationic Lignin-Based Hyperbranched Polymers to Circumvent Drug Resistance in Pseudomonas Keratitis

“…However, the copolymers did display varying levels of efficacies against different strains of bacteria. The antimicrobial activity observed for the quaternized copolymers against Gram-positive and Gram-negative bacteria could be attributed to the polyphenols present in lignin 42,43 and the cationic charge of the copolymer. 44 Considering the quaternization degree, the results obtained from the screening, and the cytotoxicity study (Figure S3), pBLD50 was selected for further studies.…”

“…However, the copolymers did display varying levels of efficacies against different strains of bacteria. The antimicrobial activity observed for the quaternized copolymers against Gram-positive and Gram-negative bacteria could be attributed to the polyphenols present in lignin , and the cationic charge of the copolymer …”

Biodegradable Polymers and Polymer Composites with Antibacterial Properties

“…Cathelicidin AMPs range from 12 to 80 amino acids and can adopt a variety of other structures. LL-37 exhibits a broad spectrum of antimicrobial activity against bacteria, fungi, and viral pathogens and plays an important role in immunomodulatory and inflammation responses [ 186 , 197 ].…”