Genetic bases of Bacillus subtilis sensitivity to Guaiacum sanctum L (Zygophyllaceae)
by Melebari, Asma, M.S., WESTERN ILLINOIS UNIVERSITY, 2010, 54 pages; 1484298

Abstract:

As microbial antibiotic resistance is rising, it is important to find novel antibiotics and study the antimicrobial resistance of the pathogenic bacteria. Guaiacum, commonly called lignum vitae, is a tropical tree genus from the family Zygophyllaceae that has been found to have some antimicrobial activities. The purpose of this study was to evaluate the antimicrobial activity of two species of Guaiacum from three different geographical regions. The study was conducted by examining the activity of Guaiacum leaf extracts on the bacterial species Bacillus subtilis.

The two Guaiacum species used in this study were Guaiacum sanctum from Costa Rica and Florida and Guaiacum officinale from Puerto Rico. The Gram-positive bacteria Bacillus subtilis was the test organism. Guaiacum activity on Bacillus subtilis was evaluated by using different methods to compare the two Guaiacum species and determine the most effective one. The comparing process was based on dilution of the extracts, extract filtration, extract time of killing, actual antibiotic activity, and geographical regions.

The results of this study have shown that the leaf extract of Guaiacum can prevent the growth of Bacillus subtilis in different levels based on the tree species and its geographical region. The extract of Guaiacum sanctum from Costa Rica showed the most activity when not diluted compared to Guaiacum sanctum from Florida and Guaiacum officinale from Puerto Rico, while the extract of Guaiacum sanctum from Florida showed the most stable activity even when diluted to 1/32.

The implication of this project would be to help in future research involving the study of the sensitive Bacillus subtilis to identify the gene or genes that are involved in the response to Guaiacum extract and the study of mutant Bacillus subtilis that showed resistance to the extract and identifying the gene(s) responsible for mutation. All these studies can help in developing novel antibiotics and finding new targets in pathogens, which is important, considering the increasing levels of antibiotic resistance in pathogenic bacteria.

 
AdviserThomas Alton
SchoolWESTERN ILLINOIS UNIVERSITY
SourceMAI/ 49-03, p. , Jan 2011
Source TypeThesis
SubjectsPlant biology; Microbiology
Publication Number1484298
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