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
The purpose of this research is to prepare new vanillic acid derivatives with 1,2,4-triazole-3-thiol heterocyclic ring and evaluate their antimicrobial activity in a preliminary assessment. A multistep synthesis was established for the preparation of new vanillic acid-triazole conjugates. The intermediate of 4-(4-amino-5-mercapto-4H-1,2,4-triazol-3-yl)-2-methoxyphenol (4) reacts with different heterocyclic aldehydes (thiophene-2-carboxaldehyde, pyrrole-2-carboxaldehyde, thiophene-3-carboxaldehyde, and furfural ) in ethanol containing few drops of acetic acid yielded the corresponding 4-(4-(substituted amino)-5-mercapto-4H-1,2,4-1triazol-3-yl)-2-methoxy phenol derivatives (5-8). These compounds were characterized spectroscopically by
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In this study, a 3 mm thickness 7075-T6 aluminium alloy sheet was used in the friction stir welding process. Using the design of experiment to reduce the number of experiments and to obtain the optimum friction stir welding parameters by utilizing Taguchi technique based on the ultimate tensile test results. Orthogonal array of L9 (33) was used based on three numbers of the parameters and three levels for each parameter, where shoulder-workpiece interference depth (0.20, 0.25, and 0.3) mm, pin geometry (cylindrical thread flat end, cylindrical thread with 3 flat round end, cylindrical thread round end), and thread pitch (0.8, 1, and 1.2) mm) this technique executed by Minitab 17 software. The results showed th
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As a result of rapid industrialization and population development, toxic chemicals have been introduced into water systems in recent decades. Because of its excellent efficiency and simple design, the three-dimensional (3D) electro-Fenton method has been used for the treatment of wastewater. The goal of the current study is to explore the efficiency of phenol removal by the 3D electro-Fenton process, which is one of the advanced oxidation processes (AOPs). In the present work, the effect of the addition of granular activated carbon (GAC) particles to the electro-Fenton system as the third electrode would be investigated in the presence of graphite as the anode and nickel foam as the cathode, which is the source of electro-generated hydrogen
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Oral tablets containing solubilized drug in the presence of appropriate excipients may give us an immediate release of the drug. Phospholipid solid dispersion (PSD) is a branch of solid dispersion in which phospholipid acts as a hydrophilic polymer in the presence of a suitable adsorbent to enhance the solubility of poorly soluble drugs. The anti-hyperlipidemic drug Atorvastatin (ATR) is an example of such drug, as it belongs to the class II group according to the biopharmaceutical classification system (BCS) with low bioavailability due to its low solubility. Phosphatidylcholine in combination with magnesium aluminum silicate as an adsorbent in a ratio of ATR: PC: MAS 1:3:4 was used to prepare ATR PSD by the solvent evaporation method, the
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In this study light elements 10B , 10Be for 10B(n,p)10Be reaction as well as proton energy from 0.987 MeV to 2.028 MeV with threshold energy (1.04MeV) are used according to the available data of reaction cross sections. The more recent cross sections data of 10Be(p,n)10B reaction is reproduced in fin steps in the specified energy range , as well as cross section (p,n) values were derived from the published data of (n,p) as a function of energy in the same fine energy steps by using the reciprocity theory of principle inverse reaction . This calculation involves only the first excited state of 10B , 10Be in the reactions 10Be(p,n)10B and 10B(n,p)10Be.
The house flies Musca domestica )Diptera:musidae) are the primary carrier of many pathogens such as cholera, typhoid, anthrax, and others. The use of chemical pesticides as a basic method of control leads to many problems at the environmental and health level. The use of safe alternatives to chemical pesticides has become an urgent necessity. The research aims to find biological alternatives that are environment-friendly and non-pathogenic to humans in controlling house flies through the possibility of extracting and diagnosing some secondary metabolites produced by the fungus Metarhizium anisopliae and testing their effects on the second larval stage of house flies using different treatment methods that include
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he effect of different cultural conditions on production of bioemulsifier from Serratia marcescens S10 was determined; different carbon and nitrogen sources were used such as: different oils include: edible (vegetable) oils (olive oil, sesame oil, sun flower oil and corn oil) and heavy oils (oil 150, oil 60, oil 40) as carbon sources and (NH4Cl, casein, (NH4)2SO4, peptone, tryptone, gelatin and yeast extract) as nitrogen sources were added to production media. Bioemulsifier was estimated by measuring the surface tension (S.T), emulsification activity (E.A) and emulsification index (E24%). The best results of bioemulsifier production from Serratia marcescens S10 were obtained at pH8 and incubated at 37ºC for 5days, using sesame oil
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Atorvastatin (ATR) is poorly soluble anti-hyperlipidemic drug; it belongs to the class II group according to the biopharmaceutical classification system (BCS) with low bioavailability due to its low solubility. Solid dispersions adsorbate is an effective technique for enhancing the solubility and dissolution of poorly soluble drugs.
The present study aims to enhance the solubility and dissolution rate of ATR using solid dispersion adsorption technique in comparison with ordinary solid dispersion. polyethylene glycol 4000 (PEG 4000), polyethylene glycol 6000 (PEG 6000), Poloxamer188 and Poloxam
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Entomopathogenic fungi can be ideal for the biocontrol of cockroaches since it is environment-friendly microbial pesticide. Susceptibility of second and fourth instar of nymphs and adults of the brown banded cockroach, Supella longipalpa (F.) (Blattodea: Blattellidae) to the entomopathogenic fungi Beauveria bassiana (Bals.) Vuill. at two concentrations 1x 107 and 1x 108 spore/ml was evaluated. Fungus was tested by using two different methods: bait and direct contact. Mortality was monitored after 3, 5 and 7 days’ post exposure. Direct contact of B. bassiana at concentration 1x 107 spore/ml produced mortality on adults 82.76% and for fourth and second instar of nymphs 82.76 and 93.10% after 7 daysâ
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