Dilsad Onbasili

Influence of Carbon Sources on The Production and Characterization of The Exopolysaccharide (EPS) by Bacillus sphaericus 7055 Strain

In this study, EPS produced by five Bacillus spp. strains was determined. The only one strain (B. sphaericus 7055) was selected due to its high EPS production and it was investigated by growing this strain in LB broth medium containing various carbon sources. The highest EPS production of this strain was found in medium containing fructose. However, the effect of different concentrations of fructose and molasses on EPS production by the strain was studied. The maximum EPS yield of the strain 7055 was recorded with 2.5% (w/v) fructose, also the highest EPS production was found in 2.5% (w/v) molasses. The strain 7055 was found to contain (98.6%) galactose and (1.4%) glucuronic acid in control medium whereas the composition of the strain 7055 (2.5% (w/v) fructose) was found to be (99.9%) neutral sugar and (0.1%) Glucuronic acid while the strain 7055 (2.5% (w/v) molasses) was found to contain (65.9%), neutral sugars and (34.1%) glucuronic acid.

Antimicrobial Activity of Mnium marginatum Extracts

The aim of this study is to observe the antimicrobial activity of Mnium marginatum extracts. In this study, 4 different solvents (acetone, chloroform, methanol and sterile distilled water (sdH2O)) were used for the extraction and the antimicrobial activity of the extracts were tested by disc diffusion method against some gram positive bacteria (Bacillus cereus ATCC 11778, Staphylococcus aereus ATCC 29213), gram negative bacteria (Escherichia coli ATCC 25922, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853, Salmonella enteritidis ATCC 13076) and yeasts (Candida glabrata RSKK 04019, Candida albicans ATCC 90028). According to the disc diffusion test results, the antimicrobial activity of chloroform extract of M. marginatum against E. coli ATCC 25922 (15 mm) was the highest when compared to others, where the lowest activity was the chloroform and sdH2O extracts against C. glabrata RSKK 04019 (6 mm).