College of Science

This study included collection of (103) swabs samples taken from patients suffering from nasolacrimal duct obstruction (NLDO) in Ibn Al- Haetham Teaching Eye Hospital /Baghdad. When these samples were cultured on special media, ninety samples gave positive results for bacteria, while no isolate was belonged to the yeast and fungi.Positive samples were identified by using cultural, microscopical and biochemical examinations for diagnosis.

A total of (500) mice of Swiss albino strain, ranged in age between (8-12) weeks old and weighed about (23-25) grams were used in this study which was divided into four parts.

    The ability of Xanthomonas campestris strain H6 for the production of α – amylase  was studied and it was found that Xc H6 is capable of producing the e xtracelluar α – amylase enzyme.  Optimal conditions for the α – amylase production in PM1 medium were studied and the higher activity of this enzyme was obtained in PM1 medium  supplemented with  glucose 3.5 %, peptone 2 %, K₂HPO₄ 2.5 %    at 30 ºC and pH 7.0.   Results obtained demonstrate that α – amylase  produced by Xc H6 is a constitutive enzyme that is not subjected to ca