This study aimed to obtain an isolate of a mold that has well characteristic for production of citric acid from raw materials available locally by solid-state fermentation and determination of the optimum conditions for production .Fourteen mold isolates producing acid were obtained from different sources, involved decayed fruits and soils. These isolates were subjected to initial qualitative screening followed by secondary quantitative screening In secondary screening a method combined between the submerged fermentation and solid-state fermentation was followed using a piece of sponge saturated by nutrients required for growth and production of acid. It was found that the isolate of A7 was the highest producer for citric acid than any other isolates including three standard isolates obtained from the Laboratory of Biotechnology/ College of Agriculture. Morphological analysis under the light microscope and cultural characteristics on solid media showed that the isolate A7 belongs to Aspergillus niger. Different raw materials were used for the production of citric acid from this isolate by solid-state fermentation included sunflower waste, wheat bran, rice bran as well as ground corn. It was found that the latter was better than others,therefore it was used for optimization of production conditions of the acid. The optimum conditions were achieved on ground corn moistened with water at a ratio 1:0.75 with an initial pH 3 inoculated with 107 spores/ml during an incubation time of 3 days at 25 C0..The productivity of citric acid under these conditions was 20.8 gm/100 gm of the media. Supporting the media with 1% of yeast extract and adding 3% of methanol to moisten solution was found to increase the productivity to 23.0 g /100 g, while the effect of ethanol was limited. Citric acid produced in this study was detected quantitatively and qualitatively by High Performance Liquid Chromatography (HPLC) and it was found that the amount of citric acid produced after three days of incubation under optimum production conditions was ١٣٫٥٤ gm/ 100 gm of media. This value was less than that estimated by the chemical method using pyridine. It was also noted that, beside citric acid, there was another compound produced in visible quantity. Although this compound was not recognized in this study, it is thought to be any of organic acids of Kreb's cycle and this compound may be interact with citric acid when determined by pyridine. According to results of determination of citric acid by HPLC it can be said that the actual production of citric acid was as mentioned above (13.54 gm/ 100 gm) but not as estimated by the chemical method using pyridine
Estimation of the names and verbs of some letters to consider the grammatical industry
The researcher was interested in studying a crucial aspect of the systematic world music culture. He highlights the analysis of the harmonic construction in the musical compositions of the artist Khalil Ismail, where harmony is a significant Western musical science, a pillar of the structure of instrumental and vocal music.
It depends on the compositions of vertical sounds performed simultaneously, as tones coincide and are sometimes dissonant to give sound resonance that enriches musical work and attracts recipients. Hence, the researcher has many questions, including: Can the composition of the writings of the artist Khalil Ismail determine in an objective research framework? Is there a study on this subject in some detail? whic
Background: Breast Lump Is The Second Most Common Presenting Symptom, After Breast Pain, To The Breast Clinic. Tru-Cut Needle Biopsy Provides Enough Tissue For Histopathological Diagnosis And Is Considered A Reliable Method For Establishing Preoperative Tissue Diagnosis.
Objectives: To Compare The Results Of Fine Needle Aspiration Cytology (FNAC), Tru-Cut Needle Biopsy With Excisional Biopsy In Detecting Breast Cancer In Palpable Breast Masses.
Results: This Study Shows That Tru-Cut Needle Biopsy Is Superior To FNAC In Confirming Breast Cancer In Palpable Breast Masses With Suspicion Of Malignancy And It Can Give Definitive Histopathological Diagnosis Of The Lesion With L
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This study examined the problem of identifying the vocabulary of the methodology of teaching Arabic language in the faculties of Media. The researcher noticed the existence of an overlap between the syllabuses of the general specialization of the Arabic language and its Media sections in the universities with the special professional vocabulary that suits the study of the media student. Thus ,this study is regarded as a real attempt to present a methodological model of media language that concerns with fillfuling students ‘linguistic and knowledgeable needs relying on measuring their benefits from the methodological Arabic curriculum . Key words:problem, teaching’ methodology of Arabic language, media language.
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Physical model tests were simulated non-aqueous phase liquid (NAPL) spill in two-dimensional
domain above the water table. Four laboratory experiments were carried out in the sand-filled
tank. The evolution of the plume was observed through the transparent side of this tank and the
contaminant front was traced at appropriate intervals. The materials used in these experiments
were Al-Najaf sand as a porous medium and kerosene as contaminant.
The results of the experiments showed that after kerosene spreading comes to a halt (ceased) in
the homogeneous sand, the bulk of this contaminant is contained within a pancake-shaped lens
situated on top of the capillary fringe.
Four genetic populations ( P1 , P2 , F1 , F2) were used in this study .
The parental cross in barley ( P1 barakq and P2 Pakistan ) was done . Many quantitative
pheno types were estimated such as plants length , tillers number , grains yield , capsules
number , the number of grains per capsule and the weight of 1000 grains . The results showed
significant differences in genetic variance values in the seconed filial generation ( F2) for all
the studied phenotypes : High values for the heritability were observed for all the studied
phenotypes .
These results indicated the effect of additive and non-additive genes on the quantitative
phenotypes . Finally , the selection of first generation can utilized for impro
Genotoxic effects of crude bacteriocin extracted from Citrobacter freundii were detected on albino mice bone marrow cells in vivo, using micronucleus (MN) and comet assay. The mice were administered intraperitoneally with 37.5, 75, 150 and 300 mg/kg of the extract for 24 hours. C. freundii was isolated from patients suffering from urinary tract infections (UTI). The bacteriocin producing isolates were determined using cup assayand the most efficient bacteriocin producers were selected. Bacteriocin was extracted from the efficient isolates via the induction with Mitomycin-C (2 mg/ml). Bacteriocin activity (320 U/ml) was determined by well diffusion method, while the protein concentration (2900µg/ml) was estim
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Abstract Inflammation of periodontal tissues is the consequence of interaction between periodontal pathogens and immune system. This is associated with increased expression of inflammatory cytokines, which may exert destructive effect to the periodontal tissues when released over long period. The aim of this study was to chronologically track the homeostasis of oral keratinocytes following removal of periodontal pathogens. This was done by investigating expression of selected inflammatory markers and integrity of epithelial monolayers in vitro. Rat oral keratinocytes were stimulated with heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis over 7-days then bacteria were washed away and epithelial cells re-cultured for 3-
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The aim of the current study was to investigate the impact of workplace stress on employee engagement within Iraqi universities through the mediator role of leadership style. Work-related stress and non-work-related stress were identified as representing workplace stress. Employee engagement has been measured through three types: social engagement, affective engagement, and intellectual engagement. Two types of leadership styles have been tested: directive and participative leadership. the structural equation Modeling was used to test the study model. A sample of 245 employees in Iraqi universities, including university professors, was targeted. Only 214 respondents participated in the survey. The results showed that non-work-relate
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