Electronic Theses and Dissertations





Date of Award


Document Type

Thesis (Campus Access Only)

Degree Name

Master of Science



Committee Chair

Tit-Yee Wong

Committee Member

Lih-Yuan Deng

Committee Member

Carlos E. Lopez- Estrano

Committee Member

King Thom Chung


Plastics are crucial part of 21st century. Each year iver 140 million tonnes of petroleum based polymers are produced and used in production of plastics. It is difficult to reduce the usage of plastc bt it is possible to replace the petroleum based chemicals with environmentally degradable plastics which have similar polymer properties. Polybetahydroxybutyrate is the best known organism that accumulates in organisms. Azotobacter vinelandii UWD is a free living soil bacteria that accumulates high levels of PHB. The objective of this research is to find an optimal growth condition for the production of PHB in this bacterium. Instead of using a classical approach in finding an optimal condition of multiple factors one at a time, a statistical approach called experimental design was used by analysing multiple factors at once. After screening for 10 factors, 3 factors namely, galactose, fructose and ammonium were proved to be important in PHB production. A.vinelandii cometabolized fructose and galactose simultaneously. Result suggested that fructose served to increase the biomass whereas, in the presence of fructose, most of the carbons from galactose were stored by the cells in the form of PHB.


Data is provided by the student.

Library Comment

Dissertation or thesis originally submitted to the local University of Memphis Electronic Theses & dissertation (ETD) Repository.