Polyphenol oxidase (PPO) is an enzyme containing copper, presents in various fruits and vegetables. It is responsible for the browning reactions when the cells are damaged during handling. The best conditions for extraction of polyphenol oxidase from banana peel was by using an extraction buffer containing phosphate buffer (0.05 M, pH 7), 0.01 M ascorbic acid and 0.5% polyethylene glycol, with extraction ratio 1:4 (w:v) for one minute by using blender. The enzyme activity was measured spectrophotometrically at 425 nm. PPO was studied to prevent the browning of banana peel which results in the loss of their marketability. The aim of this study was to determine the optimum conditions for polyphenol oxidase extraction from banana peel.
In the present work, it had been measured the concentration of radon gas (CRn) for (10) samples of cement used in constructions before and after painting them using enamel paint, purchased from the local markets, to see the extent of its ability to reduce emissions of Rn-222 in the air. These samples were obtained from different sources available in the local markets in Baghdad and other provinces. The measurements were done by the American-made detector (RAD7). The results showed that the highest CRn in the air emitted from cement samples after coating was in the cement sample (Iranian origin) where the concentration was (58.27 Bq/m3) while the lowest CRn was found in building material samples
... Show MoreThe fresh water green alga Chlorella vulgaris was selected to study its ability to degrade one of polycyclic aromatic hydrocarbon (PAHs)known is anthracene (ANT). ANT is widely used in artificial products such as wood preservatives; insecticides; dye and coating materials. This algae was cultivated in CH-10 medium under constant laboratory conditions and exposed to different concentrations (1, 3, and 5 mg/l) of anthracene for 3, 5, 7, 9 and 15 days, with the concentration of ANT measured by high performance liquid chromatographic analysis (HPLC). The results showed that C.vulgaris has high ability to reduce anthracene to 80% at 1mg/Lcon centration after 3 days and 100% after 5 days, while at 3 and 5 mg / L concent
... Show MoreThis work investigates the effect of the gas nitriding process on the surface layer microstructure and mechanical properties for steel 37, tool steel X155CrVMo12-1 and stainless steel 316L. Nitriding was conducted at a temperature of 550 °C for 2 hours during the first stage and at 750 °C for 4 hours during the second stage. SEM and X-ray diffraction tests were performed to evaluate the microstructural features and the major phases formed after surface treatment. SEM and X-ray diffraction tests were performed to assess the microstructural features and the primary phases formed after surface treatment. The new secondary precipitates were identified as γ′-Fe4N, ε (Fe2–3N), and α-Fe, exhibiting an uneven chain-like pattern wit
... Show MoreBackground: Periodontal diseases are inflammatory disorders caused by the accumulation of oral biofilm and the host response to this accumulation which characterized by exaggerated leukocytes and neutrophils attraction to the sites of inflammation by chemoattractants which are a very important part of the pathogenesis of periodontal diseases. This study aimed to determine and compare the clinical periodontal parameters and the leukocyte cell types in the peripheral blood between patients with gingivitis and periodontitis with different severities compared to healthy controls. Materials and methods: This study included 150 male subjects aged between 35-50 years. They were divided into three groups: gingivitis group (n=30), periodontitis p
... Show MoreThe lesser grain boner Rhizopertha dominica is an important insect on grain in Iraq . in this study phenol and coumarin were isolated from Albizzia lebbek . the addition of there compounds to artificial diet at concentration of 3.4,5% couse high effects on the development of the studed insect larva.the larva were unable to complete its development to adult stage. More over, using 5% coumarin larva were died.Seed germination was not affected when seed were sprayed with concentration of 3,4,5% of coumarin and phenol.
The present study introduces description of a new species of genus Arboridia Zakhvaticin 1946, based on a large collection of Cicadellids. External morphological characters particularly male genitalia were discussed and illustrated. The genus Arboridia Zalchvatkiia (Typhlocybinae: Erythroneurini) contains small slender, fragil and attractively coloured and patterned leafhoppers. It was erected by Zakhvatkin in 1946 (Zalchvatkin, 1946). The overall length of adults ranges from 2.5 to 3.4 mm. Members of this genus can be recognized by inner apical cell of forewing which is long with oblique base; Cu confluent with this base at a point near the middle of the length of inner apical cell; two prominent circular deep brown spots on vertex (Zal
... Show MoreThis study was conducted to isolate and identify killer yeast Hanseniaspora uvarum from dates vinegar and measurement the ability of this yeast to produce killer toxin. The antimicrobial activity of the concentrated supernatant containing partially purified concentrated killer toxin was also detected against several pathogenic bacteria and yeast species, which includes two types of yeast Rhodotorula mucilaginosa and Candida tropicalis and four human pathogenic bacteria Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeurginosa. In addition, the antagonistic activity of examined yeast have been studied toward four types of fungi, where two are pathogenic
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