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Background: Schistosoma mansoni is a trematode helminth responsible for liver fibrosis or cirrhosis. Aim of the work: In the present work natural products Thymoquinone loaded with chitosan nanoparticle (TQ/ChNP)) (TQ/ChNP) were used to determine their therapeutic effect on S. mansoni infection. Materials and methods: A total of 40 healthy Swiss albino mice, 20-25 g in weight, procured from Theodor Bilharz Research Institute (TBRI) Imbaba, Egypt's Schistosome Biological Supply Center (SBSC). Results: The infected mice treated with TQ/ChNP showed a significant decrease in the total worm burden. Treatment with TQ/ChNP had a highly significant effect on mature worm burden, TQ/ChNP in prophylactic and therapeutic doses significantly increased the mean number of dead ova in comparison to control. TQ/ChNP had a high decrease effect on ova count in intestinal tissue and a moderate reduction on ova count in hepatic tissue. Prophylactic dose gave a high reduction effect on ova count in intestinal tissue. As regards the size of hepatic granuloma, TQ/ChNP had the highest significant reduction on mean granuloma diameter with noticeable improvement of hepatic pathology. TQ/ChNP treated group showed observable improvement of liver pathology with mild degeneration and slight-sized fibrocellular. Conclusion: Based on the outcome of this study, TQ/ChNP proved to have potential bioactivity against S. mansoni adult stages and its potentiality in improving hepatic pathology. Efficacy of TQ/ChNP to postpone progression in chronic liver diseases must be considered as preventive medicine in patients with hepatic disorders.

Schistosomiasis is a serious parasitic infection affecting millions worldwide. This study aimed to explore the anti-schistosomal activity of curcumin and curcumin loaded gold-nanoparticles (Cur-GNPs) with or without praziquantel (PZQ). We used six groups of the C57BL/6 mice in which five groups were infected with Schistosoma Mansoni (S. mansoni) cercariae and exhibited, separately, to different treatment regimens of curcumin, curcumin loaded nanoparticle, and PZQ, in addition to one untreated group which acts as a control. Mice were sacrificed at the 8th week where both worms and eggs were counted in the hepatic and porto-mesenteric vessels in the liver and intestine, respectively, in addition to a histopathological examination of the liver granuloma. Curcumin caused a significant reduction in the worms and egg count (45.45%) at the 3rd week. A significant schistosomicidal effect of PZQ was found in all groups. Cur-GNPs combined with PZQ 97.4% reduction of worm burden in the 3rd week and the highest reduction in the intestinal and hepatic egg content, as well, besides 70.1% reduction of the granuloma size. The results suggested the curcumin in combination with PZQ as a strong schistosomicidal regimen against S. mansoni as it alters the hematological, biochemical, and immunological changes induced.

Natural bioactive materials with wound healing properties such as curcumin are attracting interest due to the emergence of resistant bacterial strains. The hydrophobicity of curcumin has been counteracted by using solubility enhancing cyclodextrins. Hydrogels facilitate wound healing due to unique properties and 3D network structures which allows encapsulation of healing agents. In this study, biosynthetic cellulose produced by Gluconacetobacter xylinus (ATCC 23770) was loaded with water soluble curcumin:hydroxypropyl-β-cyclodextrin supramolecular inclusion complex produced by a solvent evaporation method to synthesise hydrogel dressings. The ratios of solvents to solubilise curcumin and hydroxypropyl-β-cyclodextrin were tested for the production of the inclusion complex with optimum encapsulation efficacy. The results confirmed that hydroxypropyl-β-cyclodextrin enhanced the aqueous solubility of curcumin and allowed loading into bacterial cellulose hydrogels. These hydrogels were characterised for wound management applications and exhibited haemocompatability, cytocompatability, anti-staphylococcal and antioxidant abilities and therefore support the potential use of the curcumin:hydroxypropyl-β-cyclodextrin-loaded-bacterial cellulose as hydrogel dressings.

In this work, Ag doped In2O3 nanostructure materials were successfully synthesis using a simple hydrothermal process with different Ag concentration (3,6,9)%. The structural properties and morphology of the obtained nanostructure film are characterized by X-ray diffraction and field emission scanning electron microscopy (FE-SEM). The structural analysis shows a highly crystalline of indium oxide with a cubic phase and the crystallite size decreased with the increasing of doping concentration. The current–voltage results from devices indicate that In2O3 film with 9% Ag concentration has better conduction film. Gas sensing performance was studied for NO2 gas with different concentration (50,100,150) ppm at operating temperature 100 °C. The maximum sensitivity (S = 79 %) was found at doping concentration 9% Ag.

Several formulated mixtures of pesticides are widely used in modern agriculture. Nevertheless, the agriculture runoff causes a serious damage to the aquatic ecosystem. Therefore, the present study aims to use B. alexandrina snails as bioindicators for 30 g/l lambda-cyhalothrin and 17 g/l acetamiprid as a formulated mixture insecticide. Results showed that it has a molluscicidal activity against snails at LC50 7.9 mg/l. The hatchability percent of both treated 1-day-aged and/or 3-day-aged groups were less than that of the control group. The sublethal concentrations of the tested insecticide caused a remarkable abnormal necrosis in male and female gametogenic cells, besides a severe damage in both secretory and digestive cells. The results of SDS-PAGE protein profiles of treated snails showed that the least number of protein bands was noticed in snail groups that subjected to LC10 (6.6 mg/l) and LC25 (7.2 mg/l) concentrations when compared to control protein fractions.

In recent years, there has been an increasing interest in oncolytic adenoviral vectors as an alternative anticancer therapy. The induction of an immune response can be considered as a major limitation of this kind of application. Significant research efforts have been focused on the development of biodegradable polymer poly-gamma-glutamic acid (&gamma, PGA)-based nanoparticles used as a vector for effective and safe anticancer therapy, owing to their controlled and sustained-release properties, low toxicity, as well as biocompatibility with tissue and cells. This study aimed to introduce a specific destructive and antibody blind polymer-coated viral vector into cancer cells using &gamma, PGA and chitosan (CH). Adenovirus was successfully encapsulated into the biopolymer particles with an encapsulation efficiency of 92% and particle size of 485 nm using the ionic gelation method. Therapeutic agents or nanoparticles (NPs) that carry therapeutics can be directed specifically to cancerous cells by decorating their surfaces using targeting ligands. Moreover, in vitro neutralizing antibody response against viral capsid proteins can be somewhat reduced by encapsulating adenovirus into &gamma, PGA-CH NPs, as only 3.1% of the encapsulated adenovirus was detected by anti-adenovirus antibodies in the presented work compared to naked adenoviruses. The results obtained and the unique characteristics of the polymer established in this research could provide a reference for the coating and controlled release of viral vectors used in anticancer therapy.

The D.C electrical properties of (PVA–PEG–PVP–TiO2) nanocomposites for energy storage and release application have been investigated. The (PVA–PEG–PVP–TiO2) nanocomposites were prepared with different weight percentages of titanium oxide nanoparticles. Electrical properties of (PVA–PEG–PVP–TiO2) nanocomposites were studied with different temperature range. The experimental results show that the conductivity (PVA–PEG–PVP) blend is increased with increase the weight percentages of titanium oxide nanoparticles. The activation energy of (PVA–PEG–PVP–TiO2) nanocomposites decreases with increase the weight percentages of titanium oxide nanoparticles. The results of energy storage and release for (PVA–PEG–PVP–TiO2) nanocomposites show that enhancement of energy storage and release of (PVA–PEG–PVP) blend by adding of titanium oxide nanoparticles.

The D.C electrical properties of (PVA–PEG–PVP–TiO2) nanocomposites for energy storage and release application have been investigated. The (PVA–PEG–PVP–TiO2) nanocomposites were prepared with different weight percentages of titanium oxide nanoparticles. Electrical properties of (PVA–PEG–PVP–TiO2) nanocomposites were studied with different temperature range. The experimental results show that the conductivity (PVA–PEG–PVP) blend is increased with increase the weight percentages of titanium oxide nanoparticles. The activation energy of (PVA–PEG–PVP–TiO2) nanocomposites decreases with increase the weight percentages of titanium oxide nanoparticles. The results of energy storage and release for (PVA–PEG–PVP–TiO2) nanocomposites show that enhancement of energy storage and release of (PVA–PEG–PVP) blend by adding of titanium oxide nanoparticles.

Titanium dioxide (TiO2) was prepared using chemical spray pyrolysis technique on glass substrate at 350 °C with a spray rate of 5 s/1 min, for a thickness of 350 nm. The material characterization of the TiO2 nanofiber was performed using X-ray diffraction (XRD), scanning electronic microscopy (SEM), and atomic force microscopy (AFM). The optical absorption of the fibers was measured using a UV – vis spectrophotometer. The X-ray diffraction measurements confirmed that the films grown by this technique have good crystalline tetragonal anatase phase structure and with the preferred orientation along the [1 0 1] direction. The surface morphology of the TiO2 fibers showed that the micrography of the nanofiber are extra-fine. UV – vis transmittance measurements have shown that TiO2 fibers are highly transparent (∼90 (%in the visible wavelength region. The optical band gap of TiO2 fiber is 3.32 eV. The diameters of titanium dioxide nanotubes are found to be 30 – 60 nm, retaining the size and near cylindrical shape of the pores.

Nanoparticles NPS of cadmium oxide CdO were generated by laser ablation of a solid target (cadmium) in polyvinylpyrrolidone (PVP) solution. CdO colloidal nanoparticles have been synthesized by laser ablation Nd:YAG (1064 nm, 100 pulses, pulse energy= 400 mJ) when the solid target CdO was immersed in PVP. Structure, topography and optical properties of the CdO nanoparticles NPS have been studied using X-ray diffraction (XRD), atomic force microscope (AFM) and the UV-Vis absorption respectively.

SnO2 nanostructures have been prepared on quartz and porous silicon (PS) substrates using rapid photothermal oxidation at 600 °C and different oxidation times. The analysis and characterizations were researched. The photovoltage properties of Au/n-SnO2/p-PSi/c-Si solar cell are investigated under irradiation of Nd:YAG laser pulses. The PS is synthesized on single crystalline p-type Si using electrochemical etching in aqueous hydrofluoric acid at current density 25 mA/cm2 for 30 min etching time. The photovoltage properties are found to be depended on laser flounces.

Titanium dioxide (TiO2) nanotubes with an outer diameter of approximately 245 nm have been successfully prepared using an electrochemical anodization method with anodizing electrolyte containing ethylene glycol solution. X-ray diffraction (XRD) analysis shows that the TiO2 nanostructure was a crystalline anatase phase. Fabricated of dye-sensitized solar cell (DSSC) with enhanced energy conversion efficiency using TiO2 nanotubes as scattering layer was performed. Energy conversion efficiency was increased from 2.54 to 6.9%.

This study aimed to examine the chemical characteristics and antioxidant content properties of cold-pressed milk thistle seed oil. Acidity and peroxide value were determined by chemical standard titration method and oxidative stability index was determined by Rancimate. Using GLC, fatty acid composition, phytosterols and squalene were measured. While, alpha-tocopherol content was determined by HPLC. The total phenolic content, radical-scavenging capacity and total antioxidant capacity were determined spectrophotometrically. The chemical characteristics of cold-pressed oil were as follows: acidity (0.64%), peroxide value (0.34 meq O2/kg of oil), oxidative stability index (55.7 and 12.9 h at 80 and 100°C, respectively), fatty acid composition (19.5, 22.9 and 57.6% for SAT, MUFA and PUFA, respectively), phytosterol (2520 mg/kg), squalene (9.35 mg/kg), alpha-tocopherol content (237.4 mg/kg), total phenolic content (1.16 mg GAE/g oil), radical-scavenging capacity against stable DPPH radical (IC50 = 3.34 mg/mL) and total antioxidant capacity (2.29 mmol/L). These data suggest that cold-pressed milk thistle seed oil may serve as dietary source of high PUFA and MUFA, phytosterols, phenolic compounds and natural antioxidants and can be a remarkable candidate for use in healthy food preparations mixed with other vegetable oils or alone.

Indium oxide (In 2 O 3 ) nanostructures have been grown by simple evaporation method from indium metal in tube furnace at different growth temperatures (700, 800 and 900 °C). The structural properties of as prepared samples were studied by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The XRD analysis indicated that the In 2 O 3 samples are highly crystalline with a cubic phase and the average crystal size is 22.1 nm. The FE-SEM images showed the growth of nanorod and nanosheet structure. The optical properties of In 2 O 3 nanostructures were studied using UV–vis spectrophotometer. The energy gap was calculated and was found to be 3.75 eV, and this value decreases to 3.6 eV with the increasing of growth temperature.

Thin SiO2 films with thickness 5-10 nm were grown at 700°C in dry ambient. The devices with oxide 5 nm approach ideality case at room temperature, in this case thermoionic emission over the barrier is dominate mechanism with traps was dominate. Capacitance-voltagedata in the form of 1/C2 verse voltage plot has been used to extract doping on the space charge region. The barrier height from I-V calculated 0.65, 0.64 V for devices with oxide 5, 10 nm respectively, this value difference from values extract from C-V plot which found 0.57, 0.64 V.

The aim of the present study was to evaluate the efficiency of 14.5 kDa-Fasciola gigantica fatty acid binding protein (FABP) as a diagnostic antigen for human fascioliasis. 14.5 kDa FABP was isolated from the crude extract of adult F. gigantica worms by ion exchange chromatography followed by gel filtration chromatography and then analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing condition. Anti-FABP IgG polyclonal antibody (pAb) was generated in rabbits and purified by using sequential use of ammonium sulfate, caprylic acid, and then ion exchange chromatography. Conjugation of purified rabbit anti-FABP IgG with horse reddish peroxidase (HRP) was conducted and used in detecting the coproantigen in the stool and the circulating Fasciola antigen (CA) in the sera of Fasciola-infected patients using sandwich enzyme-linked immunosorbent assay (ELISA). The sensitivities of sandwich ELISA test were 96.43% and 94.74%, while the test specificities were 94.87% and 84.62% for the detection of coproantigen and CA, respectively. The parasitological diagnosis using the Kato-Katz technique revealed 64.29% sensitivity with 100% specificity. The diagnostic efficacy of sandwich ELISA was 95.52% for coproantigen and 87.93% for CA detection. In contrast, the diagnostic efficacy of Kato-Katz technique was 85.07%. It was concluded that 14.5 kDa FABP represented a valuable antigen for the immunodiagnosis of human fascioliasis using sandwich ELISA.

The vascular NAD(P)H oxidases constitute important sources of ROS in the vessel wall and have been implicated in vascular disease. Vascular smooth muscle cells (VSMCs) from conduit arteries express two gp91phox homologs, Nox1 and Nox4, of which Nox1 is agonist-sensitive. Because p22phox has been shown to be functionally important in vascular cells stimulated with vasoactive hormones, the relationship of Nox1 and p22phox was investigated in VSMCs from rat and human aortas. Coimmunoprecipitation studies demonstrated that p22phox and hemagglutinin-tagged Nox1 associate in unstimulated VSMCs. These findings were confirmed by confocal microscopy, showing colocalization of the two proteins in their native states in the plasma membrane and submembrane areas of the cell. NADPH-driven superoxide production, as measured by electron spin resonance using 1-hydroxy-3-carboxypyrrolidine as a spin probe, is dependent on the coexpression of both subunits, suggesting the importance of the association for the functional integrity of the enzyme. These results indicate that in contrast to the neutrophil enzyme, VSMCs can use Nox1 rather than gp91phox as a catalytic center in the p22phox-based oxidase and that these two proteins are preassembled at or near the plasma membrane and submembrane vesicular structures in unstimulated cells.

Angiotensin II has been shown to participate in both physiological processes, such as sodium and water homeostasis and vascular contraction, and pathophysiological processes, including atherosclerosis and hypertension. The effects of this molecule on vascular tissue are mediated at least in part by the modification of the redox milieu of its target cells. Angiotensin II has been shown to activate the vascular NAD(P)H oxidase(s) resulting in the production of reactive oxygen species, namely superoxide and hydrogen peroxide. In this article, we review what is known about the molecular steps that link angiotensin II and its receptor to production of reactive oxygen species and subsequent redox-mediated events, focusing on the structural and functional properties of the vascular NAD(P)H oxidases and their downstream mediators. As such, we provide a framework linking angiotensin II to crucial vascular pathologies, such as hypertension, atherosclerosis, and restenosis after angioplasty, by means of the NAD(P)H-dependent oxidases and their effector molecules.

This study was conducted to determine the protein quality of four types ofedible mushrooms, Terfezia claveryi, Pleurotus ostreatus, Tricholoma terreum and Agaricus macrosporus that are common inJordan. Protein efficiency ratio (PER) and net protein utilization methods(NPU) were used. The four mushroom types failed to support growth asreflected by negative values for PER; –1.76 for T. claveryi; –0.23 for P. ostreatus; –0.98 for T. terreum and–0.41 for A. macrosporus. The NPU(op), NPU(st)and NdpE% for T. claveryi were 32.6, 33.9 and 3.89%,respectively. The respective values for P. ostreatus were 38.5, 40.7and 4.35%; T. terreum 29.1, 29.8 and 3.63%; and A.macrosporus 31.5, 32.9 and 3.91%. The results showed that the fourmushrooms were significantly (p ≤ 0.05) lower in protein qualitycompared with casein results (NPU(op), NPU(st) andNDpE% of 78.5, 86.4 and 7.16%, respectively.

Staphcoccomycin (SCM) is a new member of the basic macrolide family of antibiotics which was isolated from the fermentation broth of Streptomyces sp. AS-NG 16. The production, purification and determination of physical and chemical properties of this novel metabolite have been completed. Comparison of the mass fragmentation patterns of SCM and its peracetate with those of angolamycin peracetate suggested a des-mycarosyl derivative of angolamycin. Moreover, the molecular ion peak (m/e 771) corresponded to C39H65NO14 and the 1H-NMR of SCM was also consistent with the proposed structure.

Gas liquid chromatographic analysis of the fatty acid methyl esters from eggs ofDermacentor andersoni Stiles (Ixodidae) revealed the presence of significant quantities (15% total fatty acids) of an unidentified component with a retention time between C18∶3−C22∶0 fatty acids. Smaller amounts of the unidentified component (ca. 5% total fatty acid) also were detected in host rabbit serum. Purified, the unidentified component's methyl ester collected from the tick eggs by preparative gas liquid chromatography was partially identified and characterized by chemical and spectroscopic analyses. The evidence suggests that the unidentified component is a methyl branched C15 tricarboxylic acid containing two vicinal carboxylic acid groups. Biosynthesis of the unidentified component by the tick is under investigation.

1. 1. The antibiotic ASK-753 at 10 and 20 gmg/ml lowered the transition temperature (Tm) of calf thymus DNA presumably by weakening the hydrogen bonding between the two strands. This effect might accelerate the RNA synthesis which was observed at a level of 5% of the antibiotic to the DNA. 2. 2. At the same concentration the drug degraded the calf thymus DNA as indicated by a decrease in its sedimentation velocity. Consequently, the activities of B. subtilis DNA-dependent RNA polymerase would be arrested and/or disturbed. 3. 3. A concentration of 10 μg/ml of the drug could cause degradation of the pre-labeled B. subtilis RNA, the 23 S rRNA was highly susceptible to the antibiotic.

1. 1. The effects of ferramidochloromycin (FACM) on a sensitive strain of Bacillus subtilis was examined. 2. 2. Ferrioxamine B failed to antagonize the antimicrobial effects of FACM. The antibiotic exerted no effect on the synthesis of lipids, RNA and DNA whereas it arrested protein synthesis through inhibiting lysyl tRNA synthetase and hence preventing the incorporation of [ 14 C]lysine. 3. 3. Treatment of B. subtilis with relatively high concentrations of FACM and for long incubation periods converted the cells from rod to cocci shape with the accumulation of N -acetyl aminosugars. The effect is presumably a secondary one.

N-Methyl-bis (3-mesyloxypropyl)amine hydrochloride is now in use as an antitumer drug. In view of its activity against some bacteria the present work was conducted to study its mode of action of Bacillus subtilis. The compound was found to induce irreversible damage to bacterial DNA whereas its effect on RNA was temporary and depending on maintenance of effective concentrations of the compound.

1. 1. Nilemycin (NM) is found to exert an inhibitory effect on the mouse tumor Sarcoma 180 near toxic doses but not with Leukemia 1210. 2. 2. In Yoshida rat sarcoma cells NM inhibits cellular de novo nucleic acid synthesis and protein to a much lesser extent. 3. 3. More than 50% inhibition by NM to de novo synthesis of RNA. in a system using calf thymus DNA as a template, could be observed. li|4. Suitable levels of NM reduce the S values of DNA. 4. 5. The antibiotic induced metachromatic changes in the u.v. spectrum of DNA solutions. 5. 6. NM markedly inhibited the polynucleotide ligase repairing action on DNase-1-nicked DNA. 6. 7. It is presumed that NM intercalates nicked DNA into such a configuration that the reactive sites of the polynucleotides are inaccessible to the ligase activities.

Experiments were conducted to exploit the potentialities of P. spinulosum to produce fat in submerged cultures. The organism was grown in shaken submerged cultures with different levels of glucose content. The addition of the sugar to preformed mycelium was also examined and the mould was cultivated in a Waldhof fermentor. Finally, a study was made of the effect on the behaviour of the organism of the metabolism solution obtained from previous experiments.

A new iron-containing peptide which inhibits the growth of Gram-positive and some Gram-negative bacteria was isolated from the broth of Streptomyces AS-K-753. The antibiotic was obtained as light buff plates. On acid hydrolysis eight amino acids, three organic acids and one keto acid could be detected.ASK-753 is similar in many properties to the sideromycin but differs from it in certain crucial characteristics.

The breakdown of itaconic acid by preformed mats of a local strain of Aspergillus terreus was studied using the zone-strip technique. Low pH values restrained the uptake of itaconic acid and the accumulation of various other acids while higher pH values exerted an opposite effect. The results obtained when using various enzyme inhibitors were those anticipated on basis of the direct transformation of itaconic to aconitic acid through the fixation of CO2 and of the existence of the T.A.C. (tricarboxylic acid cycle) as a main metabolic channel operating in this organism.

The taxonomical characters of the three Egyptian willows—Salix babylonica (Linne), Salix Safsaf (Forsk.), and Salix tetrasperma (Roxb.)—have been studied. The pharmacognostical study of the barks and leaves of the three species has been carried out. The active bitter constituent of the barks and leaves has been isolated and was proved to be the glycoside salicin.

The formation of fat from citric, succinic, fumaric and malic acids by Penicillium spinulosum has been investigated. Sodium arseite, β-sulfonic propionic acid and mono-iodoacetate was found to control unfavourably the formation of fat from the organic acids by the preformed pellets of the organism. Moreover, iodoacetate reduced the mean molecular weight of the component fatty acids. The β-sulfonic propionic acid though reduced the yields of fat yet the ratio fat/100 g of acid consumed was not markedly altered by this compound. A modified chromatographic method was described for the assay of different acids.

The effects on the A. niger fermentation of sucrose and molasses exerted by various concentrations of ethanol, acetate and pyruvate are examined in presence of the optimum concentrations of ferrocyanide and phosphate. Such mixtures gave appreciable increases in the yields of citric acid with also traces of oxalic acid and the time of incubation could be reduced. The behaviour of two potent citric-acid-producing strains of A. niger on molasses medium supplemented with methanol was also studied. The results are discussed in the light of well-known metabolic pathways.

A new antibiotic, gluconimycin, was isolated from Streptomyces AS 9. The systematic position of the organism is discussed. Gluconimycin has a polypeptide nature. It contains iron and gluconic acid in its molecule. Thus it has been classified as a member of sideromycins. Gluconimycin is considered from the fast moving type when chromatographed by butanolacetic acid-water. The antibiotic is active against Gram+ve, Gram-ve bacteria and some fungi. The antibiotic exerts high toxicity when injected in mice.

Studies are made of the effects of the following factors influencing the free acidity of the fat of P. spinulosum : (1) sterilisation of the felts in their metabolism solutions and when floated on distilled water; (2) the initial pH value of the medium; (3) addition of calcium carbonate to stabilise the pH of the medium at near neutrality during incubation; (4) the presence of glycerol as well as glucose in the medium; (5) addition of sodium sulphite. The results are discussed in relation to the metabolic processes of the mould.

The formation of itaconic, aconitic and other acids from glucose in the presence of some enzyme inhibitors or organic acids by Aspergillus terreus was studied. Moreover, the metabolic activities of the preformed mats when floated on solutions of some organic acids were traced. When the resulting information were collected together a presumed condensation reaction between acetate and succinate could be formulated. The reaction product, presumably 1, 2, 3 propane tricarboxylic acid, would undergo a dehydrogenation reaction to yield aconitic acid and subsequently itaconic acid. It has also been suggested that aconityl CoA may be the metabolic form which suits the reactions leading to the formation of itaconic acid. The presumed aconityl CoA may be formed either through a condensation reaction between acetyl CoA and succinate or acetate with succinyl CoA.

The thermal evaporation system type (Edwards) has been used to evaporate high purity (99.9 %) silver on glass, n- and p-type silicon and porous silicon substrates at room temperature under low pressure (about 10−6 torr) for different thickness (50, 75, 100, 125 and 150 nm). Using a rapid thermal oxidation of Ag film at oxidation temperature 350 °C and different oxidation times, Ag2O thin film was prepared. The structural properties of Ag2O film were investigated and compared with other published results. The structural investigation showed that the films formed at thickness 100 nm showed (111) strong reflection along with weak reflections of (101) corresponding to the growth of single phase Ag2O with cubic structure. Dark and illuminatedI–V of p-Ag2O/p-Si, p-Ag2O/n-Si, Al/p-PSi/Al, Al/n-PSi/Al, p-Ag2O/p-PSi/c-Si and p-Ag2O/n-PSi/c-Si heterojunction were investigated, discussed and prepared at optimum condition (oxidation temperature 350 °C and 90 s oxidation time with thickness 100 nm). Ohmic contacts were fabricated by evaporating 99.999 purity silver wires for back and aluminum wires for front contact, respectively.

A study is made of the formation of fat and of citric acid by preformed pellets of P. spinulosum suspended in either sucrose or citric acid solutions supplemented with monoiodo-, monobromo- or monochloro-acetates. The weights of felts, their fat contents and the concentrations of citric acid and of sucrose were all determined.

Kuwaitimycin influences the translocation of alkali metal cations in liver mitochondria.In presence of valinomycin, which stimulates uptake of potassium ions by the mitochondria, the addition of kuwaitimycin could augment the loss of these ions when the source of energy was mainly an oxidizable substrate. However, kuwaitimycin fail ed to cause loss of K+ from mitochondria in presence of appropriate amounts of ATP. A relation between the ionic size of the alkali metal cations and the inhibiting effect of the antibiotic on glutamate oxidation could be demonstrated. The ability of kuwaitimycin to restrain ATP supported oscillatory swelling associated with alkali metal cations transport induced by monazomycin was also demonstrated. The more voluminous the cation the more pronounced the effect on cation transport. The effect of kuwaitimycin on ATP hydrolysis in presence of different alkali metal cationswas found to be weak and independent or the cationic size.In light of the results obtained it is suggested that the antibiotic is exerting its effect on ion transport by inducing pores in the mitochondrial membrane and that the addition of appropriate amounts of ATP might alter the conformation of the mitochondrial membrane in such a way as to nullify the effect of the antibiotic.

The mode of action of ASK-753 on Bacillus subtilis was examined. Unlike proper sideromycin antibiotics ferrioxamine B failed to antagonize the antimicrobial effects of ASK-753. The antibiotic could inhibit the biosynthesis of nucleic acids; effect on the RNA was more pronounced. ASK-753 affected the stability of prelabelled DNA of B, subtilis in growing or resting cultures; the effect on the latter was more pronounced. Lysis of B, subtilis protoplasts could be attained at 30 degrees C but not at 4 degrees C which excludes a possible detergent affect of the drug. The drug exerted a potent inhibiting influence on protein synthesis by arresting the activity of lysyl-tRNA synthetase and thus could prevent the incorporation of 14C-lysine.

4,4′-Isopropylidine-bis[2-isopropyl]phenol was found to possess antimicrobial activity against gram-positive bacteria and some fungi, whereas it had no effect on gram-negative organisms. The drug has a potent inhibitory action on the synthesis of cell wall mucopeptides of Bacillus subtilis by inhibiting the enzyme d -glutamate ligase, which is responsible for the incorporation of d -glutamic acid into uridine 5′-diphosphate-muramyl- l -alanine. The drug had a weak lytic effect on protoplasts and inhibited protein synthesis, whereas no significant effect on the synthesis of deoxyribonucleic acid and ribonucleic acid was found.

Cairomycin B is a new cyclic peptide antibiotic that was isolated from Streptomyces As-C-19 obtained from the soil of Cairo. The antibiotic had the following empirical formula: C 10 H 15 N 3 O 3 ; on acid hydrolysis, it yielded aspartic acid and lysine. Spectral analysis and its chemical characteristics indicated that it was a cyclic peptide. The antibiotic melted at 120 to 121°C and was freely soluble in chloroform, ethyl acetate, and acetone, slightly soluble in alcohols, and rather insoluble in water and petroleum ether. Cairomycin B was mainly active against gram-positive bacteria, with high toxicity to experimental animals and weak serum-binding properties.

The present study was conducted to determine how hodydamycin inhibits microbialgrowth. Hodydamycin had no effect on either the cell membrane or the synthesis ofthe cell wall of susceptible organisms. The antibiotic inhibited protein synthesis throughits scissating effect on DNA. No effect on the synthesis of RNA was observed.

1. 1. Cairomycin B (CB) inhibits nucleic acid and protein synthesis in cells of Staphylococcus aureus. 2. 2. The antibiotic elevated the Tm of DNA while that of RNA was lowered. 3. 3. DNA dependent RNA polymerase was inhibited by the antibiotic. 4. 4. Sedimentation properties of DNA & RNA with CB showed an increase in their S values. Sedimentation analysis for mixtures left after Tm determination showed the same pattern as the unheated mixture containing DNA whereas that containing RNA revealed fewer fractions. 5. 5. The [3H]CB bound with [14C]DNA and with ribosomal RNA; mainly the 50 S subunits and the 70 S as well. 6. 6. CB was found to interfere with polypeptide chain elongation but not with the initiation step. 7. 7. Miscoding induced by CB during polypeptide synthesis through misreading of U as A in 5-terminal of UUU triplet was also demonstrated.

The antibiotic action of poly ketoacidomycin (PKAM) on Bacillus subtilis was examined. PKAM stimulated the turnover of phosphatidyl glycerol (PG) to cardiolipin (DPG) and reduced the amounts of the normal fatty acids (nFAs) C-14 and C-16 and anteiso (a) C-17. Addition of bacterial PG to cultures treated with PKAM reduced the effect of the antibiotic.The foregoing changes in lipid composition were associate d with changes in cell permeability . Loss of cellular valine, norvaline and phosphates was observed and a significant decrease in the cellular concentration of Na+ and K+ ions was noted when the test organism was incubate d with PKAM for periods up to 15 minutes. Longer incubation of the bacteria with the antibiotic caused an appreciable increase in RN A content of the cells and a reduction in the DNA and protein content. Polyketoacidomycin (PKAM), first isolated b y SHIMI et al., 1) possesses substantial anti-microbial activity against gram-positive bacteria as well as some gram-negative bacteria. The acid hydrolysate of the antibiotic contains glucose, alanine, and acetone, as well as pyruvic, glyoxylic, α-ketoglutaric, α-ketobutyric and acetoacetic acids.

Hodydamycin is a new antibiotic which has been isolated from Streptomyces AS-Y-400 obtained from the soil of Yemen. The antibiotic strongly absorbs iodine and yields five aminoacids on acid hydrolyses. It melts at 145°C and shows an ultraviolet absorption maximum at 249 mμ (E1%1cm 358) in neutral and acidic ethanol. Hodydamycin is strictly active against Gram-positive bacteria, possesses low toxicity and markedly high serum binding property.

1. Penicillium chrysogenum and Aspergillus flavus degraded benzylpenicillin in the same way. 2. Degradation of the antibiotic was initiated by the cleavage of phenylacetic acid from 6-aminopenicillanic acid. 3. Phenylacetic acid was left unchanged whereas 6-aminopenicillanic acid was degraded into cysteine and valine. This reaction is probably complex. 4. Cysteine was not utilized but valine was cleaved into acetone and glycine. Catabolism of valine by the preformed mats of the two moulds confirms this result. This step probably involves the formation of propan-2-ol. 5. Cleavage of benzylpenicillin into phenylacetic acid and 6-aminopenicillanic acid was performed through the activity of a cellular-bound enzyme.

1. The formation of valine from acetone and glycine and from propan-2-ol and glycine was demonstrated. The transformation of propan-2-ol to acetone was suggested. 2. Acetone, propan-2-ol, glycine, valine and cysteine stimulated the biosynthesis of 6-APA when supplemented separately to the medium. These compounds are arranged in a descending order with respect to their stimulative influence. 3. Coenzyme A influenced favourably the formation of 6-APA. 4. A mixture of acetone, glycine, and cysteine was the most stimulative among the other combinations tried. 5. A presumed sequence of reactions between acetone, glycine and cysteine, probably involving CoA, was thus suggested for the biosynthesis of 6-APA. The reactions involve dehydration and dehydrogenation with the liberation of two molecules of water and two hydrogen atoms.

Isolation of a crystalline fibrinolytic activator from metabolites of Bacillus subtilis was performed by salting out with ammonium sulphate and final precipitation by gradual addition of acetone. The degree of purity of the activator at the different stages of purification was tested by paper electrophoresis and starch block electrophoresis. The activator failed to attack casein, pure fibrin, gelatin and egg albumen. The reaction between the crystalline activator and plasminogen and the effect of the resulting product on fibrin were traced by paper chromatography and by recording the UV spectra of the reacting system. Finally the effects exerted by some factors on the liquefaction of the human blood clots by the activator were investigated.

The effects of yemenimycin on the growth and contents of DNA, RNA and proteins of Candida albicans were appraised. Glycolysis and aerobic respiration were less sensetive to the antibiotic than the syntheses of nucleic acids and proteins. Incorporation of P-32 in DNA and RNA was markedly arrested by yemenimycin whereas the contents of the labeled supplement in TCA soluble fraction and phospholipids were appreciably augmented. Yemenimycin restricted the incorporation of C14-thymidine and to a lesser extent of C14-uridine in Bacillus subtilis cells while the incorporation of H3-lysine in cellular protein was relatively the most resistant. Synthesis of aminoacyltRNA and the binding of C14-phenylalanyl-tRNA to ribosomes in response to poly U were found to be rather insensitive to the drug. Finally the effect of yemenimycin on the protein synthesis of intact rabbit reticulocytes and their cell-free system was assessed. The antibiotic could influence unfavorably the synthesis of protein.