Type
Text
Type
Thesis
Advisor
Meng, Yizhi | Gersappe, Dilip | Boon, Elizabeth.
Date
2013-12-01
Keywords
Materials Science | antibacterial, Anti-biofilm, chitosan, chitosan/TPP nanoparticle, proanthocyanidin
Department
Department of Materials Science and Engineering.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76346
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Biofilm-forming bacteria are a form of planktonic microorganisms that can become resistant against conventional antibiotics. Because they are difficult to eradicate, biofilm-forming bacteria are extremely problematic for the medical industry areas. Thus, materials that can distort biofilm structure would be helpful for eliminating chronic infection and decreasing bacterial resistance. The primary objective of this study is to evaluate the anti-biofilm effect of two bio-derived substances, proanthocyanidin and chitosan. Proanthocyanidins are secondary plant metabolites that are reported to have antibiotic and antioxidant functions. Chitosan is a deacetylated derivative of chitin, which is abundant in the exoskeleton of crustaceans and insects. It is reported to be a suitable substitute for conventional fungicides and can enhance the proanthocyanidin content in plants when used as an agrochemical. Chitosan-tripolyphosphate (TPP) nanoparticles, which have good neutral water solubility and are nanoscale in size, can be used as carriers for gene and drug therapy and are thus favorable to be tested as a treatment method against bacterial biofilms. In this study, the anti-biofilm and antibacterial properties of proanthocyanidin, chitosan-TPP nanoparticles and proanthocyanidins-loaded chitosan-TPP nanoparticles were tested using the model plant bacterium, Pseudomonas syringae pv. papulans (Psp), a pathogen isolated from infected apples. At a lower concentration (1 mg/mL and 2.5 mg/mL), both chitosan nanoparticles and proanthocyanidins can postpone the formation of biofilms and eventually disrupted part of the biofilm. While higher concentration (above 5 mg/mL) of chitosan nanoparticles or proanthocyanidins can eliminate most of the biofilm in this study. PAC-loaded chitosan nanoparticles also can also distort biofilms. Both proanthocyanidins and chitosan-TPP nanoparticle showed a mild antibacterial property. PAC-loaded chitosan-TPP nanoparticle exhibited a stronger and durable antibacterial property. | 70 pages
Recommended Citation
Song, Kai, "An in vitro study of the anti-biofilm properties of proanthocyanidin and chitosan in Pseudomonas syringae pv. papulans" (2013). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2270.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2270