Antibiofilm Properties of Interfacially Active Lipase Immobilized Porous Polycaprolactam Prepared by LB Technique

Abstract

Porous biomaterial is the preferred implant due to the interconnectivity of the pores. Chances of infection due to biofilm are also high in these biomaterials because of the presence of pores. Although biofilm in implants contributes to 80% of human infections [1], there are no commercially available natural therapeutics against it. In the current study, glutaraldehyde cross linked lipase was transferred onto a activated porous polycaprolactam surface using Langmuir-Blodgett deposition technique, and its thermostability, slimicidal, antibacterial, biocompatibility and surface properties were studied. There was a 20% increase in the activity of the covalently crosslinked lipase when compared to its free form. This immobilized surface was thermostable and retained activity and stability until 100°C. There was a 2 and 7 times reduction in carbohydrate and 9 and 5 times reduction in biofilm protein of Staphylococcus aureus and Escherichia coli respectively on lipase immobilized polycaprolactam (LIP) when compared to uncoated polycaprolactam (UP). The number of live bacterial colonies on LIP was four times less than on UP. Lipase acted on the cell wall of the bacteria leading to its death, which was confirmed from AFM, fluorescence microscopic images and amount of lactate dehydrogenase released. LIP allowed proliferation of more than 90% of 3T3 cells indicating that it was biocompatible. The fact that LIP exhibits antimicrobial property at the air-water interface to hydrophobic as well as hydrophilic bacteria along with lack of cytotoxicity makes it an ideal biomaterial for biofilm prevention in implants.

Papain immobilized polyurethane as an ureteral stent material

“…This leads to leakage of cell content from the cell, resulting in bacterial damage. Literature states that protease act by hydrolysing the protein present on a bacterial surface . Fluroscence images [Figure (C,D)] indicate cell wall damaged bacteria (red color due to the penetration of propidium iodide) on the papain immobilized PU.…”

“…These small pieces of PU were incubated in a flask containing a mixture of 0.5% of glutaraldehyde mixed with 25 mM of phosphate buffer. The pH of this solution was maintained at 7.0 . The flask was stirred mildly for 15 h at a temperature of 25°C.…”

“…The water contact angle of the PU surface was measured using a method known as the sessile drop technique with the help of a Goniometer (manufactured by Kruss, Germany) . A PU film sample was positioned on a small glass piece.…”

A halotolerant thermostable lipase from the marine bacteriumOceanobacillussp. PUMB02 with an ability to disrupt bacterial biofilms

“…[20][21][22] Lipases from microorganisms are currently the focus of much interest given their large potential in a wide variety of industrial applications in the food, pharmaceutical, cosmetics, fine chemical and dairy industries amongst others coupled with their potential use in anti biofouling 8,23 and anti-biofilm strategies. 24 Following screens involving both tributyrin and olive oil plates a bacterial strain (PUMB02) with good activity was isolated, which, following phylogenetic analysis, was classified as an Oceanobacillus species. Oceanobacillus is a genus in the family Bacillaceae which include the genus Ornithinibacillus which can be differentiated based on the unique feature of the presence of l-ornithine in the peptidoglycan.…”

Prevalence of lipase producer Aspergillus niger in nuts and anti-biofilm efficacy of its crude lipase against some human pathogenic bacteria

“…Biofilm is a complex medium involving live and dead bacterial cells, exopolysaccharides, proteins and carbohydrates on a material surface with a serious problem in biomedical applications 16 . Several steps were involved in biofilms development beginning with surface adherence, microcolony formation, maturation and finally detachment stages 17 .…”