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
A comparative study was done on the adsorption of methyl orange dye (MO) using non-activated and activated corn leaves with hydrochloric acid as an adsorbent material. Scanning electron microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR) were utilized to specify the properties of adsorbent material. The effect of several variables (pH, initial dye concentration, temperature, amount of adsorbent and contact time) on the removal efficiency was studied and the results indicated that the adsorption efficiency increases with the increase in the concentration of dye, adsorbent dosage and contact time, while inversely proportional to the increase in pH and temperature for both the treated and untreated corn leav
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The extraction of Eucalyptus oil from Iraqi Eucalyptus Camadulensis leaves was studded using water distillation methods. The amount of Eucalyptus oil has been determined in a variety of extraction temperature and agitation speed. The effect of water to Eucalyptus leaves (solvent to solid) ratio and particle size of Eucalyptus leaves has been studied in order to evaluate the amount of Eucalyptus oil. The optimum experimental condition for the Eucalyptus oil extraction was established as follows: 100˚C extraction temperature, 200 rpm agitation speed; 0.5 cm leave particle size and 6:1 ml: g amount of water to eucalyptus leaves Ratio.
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An experimental study was conducted with low cost natural waste adsorbent materials, barley husks and eggshells, for the removal of Levofloxacine (LEVX) antibacterial from synthetic waste water. Batch sorption tests were conducted to study their isothermal adsorption capacity and compared with conventional activated carbon which were, activated carbon > barley husks > eggshells with removal efficiencies 74, 71 and 42 % with adsorbents doses of 5, 5 and 50 g/L of activated carbon, barley husks, and eggshells respectively. The equilibrium sorption isotherms had been analyzed by Langmuir, Freundlich, and Sips models, and their parameters were evaluated. The experimental data were correlated well with the Langmuir model which gives the
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The nanostructured MnO2 /carbon fiber (CF) composite electrode was prepared using the anodic electrodeposition process. The crystal structure and morphology of MnO2 particles were determined with X-ray diffraction and field-emission scanning electron microscopy. The electrosorptive properties of the prepared electrode were investigated in the removal of cadmium ions from aqueous solution, and the effect of pH, cell voltage, and ionic strength was optimized and modeled using the response surface methodology combined with Box–Behnken design. The results confirm that the optimum conditions to remove Cd(II) ions were: pH of 6.03, a voltage of 2.77 V, and NaCl concentration of 3 g/L. The experimental results showed a good fit for the Freundli
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Background: Bacteriocin is a peptidic toxin has many advantages to bacteria in their ecological niche and has strong antibacterial activity. Objective: The aim of this study was to evaluation of bacteriocin using Streptococcus sanguinis isolated from human dental caries.
Subjects and Methods: Thirty five streptococcus isolates were diagnosed and tested for their production of bacteriocin, and then the optimal conditions for production of bacteriocin were determined. After that, the purification of bacteriocin was made partially by ammonium sulfate at 95% saturation levels, followed by and gel filtration chromatography
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Acinetobacter baumannii received attention for its multi-drug resistant associated with many severe infections and outbreaks in clinical environment. The aims of the study are to investigate the antibiotic susceptibility profile of clinically isolated A. baumannii, biofilm production, and the efficiency of Low Frequency Ultrasound (LFU) and honey to attenuate biofilm production. A total of 100 samples were taken from different sources from Baghdad hospitals. The susceptibility patterns revealed the percentage of pan drug resistant (PDR) isolates were 1.5 %, 72.7 % were extended drug resistant (XDR), 16.7 % were multidrug resistant (MDR), and 9.1 % were non MDR and sensitive to most antibiotics used. The ability to form
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Abstract:
Saudi Arabia and United States long relation could present an important
subject to understand alliance kind in international relations types. We trying
in this study to diagnose and analyze the Saudi Arabia and United States
model to find balance and unbalance statues and its influence on the
directions of Saudi Arabia foreign policy positions.
We divided the study in two parts, each part have many sections. The
first part deal with the historian emergence of Saudi Arabia state and its
development in three stages including its foreign relations with regions and
international powers. While the second part was dedicated in analyzing and
understanding the mechanism and active facts that drawing the Sa