Seven [35%] and five [25%] Serratia marcescens isolates were obtained out of 20 samples of lettuce and 20 samples of spinach, respectively, taken from different locations in a farm in Baghdad city. The isolate that produced chitinase in higher level was chosen to purify chitinase through several stages of purification including: ammonium sulfate precipitation, DEAE- sephadex ion exchange chromatograpgy and sephadex G-200 gel filtration with 89.5- fold purification and 30% recovery. The purified chitinase was characterized and the molecular weight of enzyme was 59000 daltons by using gel filtration chromatography. The optimum pH and temperature of the purified chitinase were 6.0 and 50° c, respectively, and the purified enzyme was stable on pH 5-7 up to 50° c. The enzyme was activated by Ca+2 , Cu+2 , Mg+2 and inhibited by Hg+2. In addition , Triton x-100 and n-ethylmaleimide increased the chitinase activity while EDTA, methanol, ethanol and acetone inhibited enzyme activity; and this indicates that chitinase is a metaloenzyme. Chitinase showed stronger inhibitory activity to Fusarium solaini compared with Aspergillus flavus with percent of inhibition 83 and 69%, respectively . Therefore, this research leads to increase interest by using the chitinase as biocontrol agent of phytopathogenic fungi and insects , production of chito –oligosaccharides,preparartion of sphaeroplast and protoplast from yeast and fungi and bioconversion of chitin waste to single cell protein for animal feed.
Background: Extended-spectrum β-lactamases (ESBLs), including cefotaximases (CTX-M), mediate resistance to extended spectrum cephalosporins and significantly compromise the treatment tools for Shigellosis.
Objective: To determine the ESBLs production by Shigella spp. and its role in the resistance to third generation cephalosporins and to determine the occurrence of plasmid- borne blaCTX genes in ESBLS Shigella isolates by Multiplex PCR.
Methods: Susceptibility of 59 clinical Shigella isolates was tested by disk diffusion method to six antimicrobial agents. Presence of ESBL
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Bacteriocin is an important antimicrobial peptide that can be used in industrial and medical fields due to its characteristics of antibacterial, food preservation and anticancer activities. Fifty isolates of Bacillus sp were collected from different soil samples which were already recognized via morphological and biochemical identification process. The isolates were screened for bacteriocin production effective against Staphylococcus spp in order to select the highest producing isolate. The isolate NK16 showed the maximum bacteriocin production (80 AU/ml) which was further characterized as Bacillus subtilis NK 16 through using API identification system (API 20E and API 50CHB). Then, next step was to detect the optimal conditions for maximum
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In this study, detection of uricase production from Pseudomonas aeruginosa
isolates was done by applying colorimetric method, Uricase was purified from the
most potent isolate by precipitation using ammonium sulphate (80% saturation) then
purification was achieved using DEAE –Cellulose ion exchange and Sepharose 6B
gel filtration chromatography column, 16.4% of total enzyme was recovered with
specific activity 2337.5U/mg and 22.21folds of purification. Characterization of
uricase involved detection of optimal conditions for uricase activity, the maximal
activity was obtained at temperature 45ºC,while uricase appeared to be stable at
40ºC. Uricase showed optimal activity at pH 9 while pH stability was in the
ABSTRACT
This research included the preparation and characterization of new demulsifies from natural and synthetic polymers of chitosan and polyvinyl alcohol that are environmentally friendly and at the same time have high efficacy comparable to emulsifiers. imported foreign. The prepared compounds were examined using infrared spectroscopy and nuclear magnetic resonance spectroscopy, and all the spectral signals of the polymers were in good agreement with the chemical composition of the polymers. And the melting and decomposition that occur on polymers at high temperatures. The effect of the length and type of side chain in the compositions of polymers on the process of water separation of oil emulsions w
... Show MoreIsolation of fungi was performed from February to July, 2019. One hundred clinical specimens were collected from King Abdullah Hospital (KAH) Bisha, Saudi Arabia. Samples were collected from twenty patients of different ages (30 - 70 years old) ten males and ten females. The samples were collected from patients with the two types of diabetics. Specimens included blood, hair, nail, oral swabs and skin. Specimens were inoculated on Sabourauds Dextrose agar containing chloramphenicol. Thirteen fungal species were isolated and identified. The isolated species were: Aspergillus flavus, A. niger, A. terrus, A. nidulans, A. fumigatus, Candida albicans, C. krusei, C. parapsilosis, C. Tropicalis, Curvularia lunata, Fusarium solani, Penicill
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Ninety five samples were collected from different samples (urine, ear and wounds swaps), from hospitals in Baghdad city. The results of cultural, microscopic , biochemical tests indicated that in urine samples E.coli have high occurrence frequency 19 (47.5%) followed by Proteus mirabilis 18(45%) and Klebsiella species 1 (2.5%), while in wounds samples each of Pseudomonas spp. and Proteus mirabilis 10 (25%) , then followed by E.coli with 5 (12.5%) and Klebsiella species 3 (7.5%). Ear swaps samples revealed that Pseudomonas aeruginosa 7 (46%) was the major bacterium followed by Proteus mirabilis 4(26.6).Sensitivity test against eleven antimicrobial agents was done for all of the Proteus mirabilis isolates (32 isolates). The results display
... Show MoreA total of 172 clinical were obtained over 6 months. Klebsiella spp. was detected in 58 (33.7%) samples with a high percentage 29 (50%) in urine in female and low percentage 1(1.7%) in pus and burn swabs in male, and the vaginal swab was 1(1.7%). The female to male ratio was 3.1:1. PCR detection showed that 51(87.93%) out of 58 produce 108 bp. product with rpoB specific primer that represented K. pneumonia. Whereas 7(12.07%) showed PCR product with 343 bp by K. oxytoca specific primer (peh X), furthermore, the sequences of two selected isolates showed that the species related to K. oxytoca strain CAV1335, and to K. oxytoca strain CAV1374. Five selected isolates were re-tested by the gyr A primer, all were showed specific band product wit
... Show MoreSchiff bases were prepared prepared Baaan NMR to some elements of which have contributed to the results of different methods in diagnosis prove structural formulas of compounds prepared
The objective of this study is to test In Vitro the twenty chemical compounds that contains Schiff base or oxazepine, indoline, imidazolo units in concentrations( 50, 100, 150) mg / dl as antifungal activity, against three pathogenic Candida species that occur in humans. We tested one isolates of
) Candida albicans ,Candida glabrata and Candida krusei). All these species affect human health . The study was carried out in the Laboratory of Public Health , directly of health for the period from May 2016 to April 2017 , Candida spp isolates used in this study were collected from patients admitted at some private c
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