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.
This research work aims to the determination of molybdenum (VI) ion via the formation of peroxy molybdenum compounds which has red-brown colour with absorbance wave length at 455nm for the system of ammonia solution-hydrogen peroxide-molybdenum (VI) using a completely newly developed microphotometer based on the ON-Line measurement. Variation of responses expressed in millivolt. A correlation coefficient of 0.9925 for the range of 2.5-150 ?g.ml-1 with percentage linearity of 98.50%. A detection limit of 0.25 ?g.ml-1 was obtained. All physical and chemical variable were optimized interferences of cation and anion were studied classical method of measurement were done and compared well with newly on-line measurements. Application for the use
... Show MoreSami Michael and Eli Amir - two Israeli writers born in Iraq and of the same generation (Sami Makhail was born in Baghdad in 1926 and Eli Amir in 1937). They wrote in their novels, among other things, about Orientalism , love and femininity. They both lived wild, extroverted lives. They did not shy away from experiencing anything new that came their way, rebelled against conventions and acted provocatively; they enjoyed the shock and amazement that evoked around them. While trying to find their place in different family settings, they chose to present two Arab Christian heroines. The narrator in Jasmine is the speaker Noori-Eli himself. While the narrator of “Trumpet in the Wadi” is Huda the heroine herself. Both ar
... Show MoreThe existing investigation explains the consequence of irradiation of violet laser on the structure properties of MawsoniteCu6Fe2SnS8 [CFTS] thin films. The film was equipped by the utilization of semi-computerized spray pyrolysis technique (SCSPT), it is the first time that this technique is used in the preparation and irradiation using a laser. when the received films were processed by continuous red laser (700 nm) with power (>1000mW) for different laser irradiation time using different number of times a laser scan (0, 6, 9, 12, 15 and 18 times) with total irradiation time (0,30,45,60,75,90 min) respectively at room temperature.. The XRD diffraction gave polycrysta
... Show MoreIn this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
... Show More