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Full Length Research Paper
Abstract: Molecular dynamics simulations may be used to probe the interactions of membrane proteins with lipids and with detergents at atomic resolution. Examples of such simulations for ion channels and for bacterial outer membrane have already been studied. The molecular potassium channel function is universally conserved. Potassium channels allow potassium flux and are essential for the generation of electric current across excitable membranes. Potassium channels are also the targets of various intracellular control mechanisms, such that the suboptimal regulation of channel function might be related to pathological conditions. Realistic studies of ion current in biologic channels, present a major challenge for computer simulation approaches. In this work, to characterize protein behavior, we observed quantities such as gyration radius and energy average. We studied the changes of these factors for voltage – gated potassium channel protein in gas phase with native conformation by Monte Carlo, Molecular and Langevin Dynamics simulations. Monte Carlo simulation is a stochastic method and therefore, is the best method to evaluate the radius of gyration. When the temperature is increased the kinetic energy is increased too and its correlation is linear. All the calculations were carried out By Hyperchem 8.0 program. The determination of gyration radius is spectacular for configuration of a macromolecule. It also reflects molecular compactness shape. The radius of gyration is calculated by VMD 1.8.7 software.[...] Read More.
Keywords: Monte Carlo simulation, molecular dynamics simulation, Langevin dynamics simulation, protein folding, gyration radius.
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Full Length Research Paper
Abstract: The objectives of this study were to examine methicillin-resistant Staphylococcus aureus (MRSA) strains recovered from major hospitals in King Saudi Arabia (KSA) to determine the percent of community acquired MRSA (CA-MRSA) phenotypically by conventional methods and genotypically by multiplex polymerase chain reaction (multiplex-PCR) for direct and simultaneous detection of S. aureus 16S rRNA, Panton–valentine leucocidin (PVL ) and staphylococcal cassette chromosome mec (SCCmec) type IVa genes. Therefore, 135 strains of S. aureus collected during the period of 2008 and 2009 from major hospital laboratories and public health centers, Riyadh, King Saudi Arabia were tested phenotypically by conventional methods and genotypically by multiplex-PCR. PCR enables rapid detection of all 135 bacterioloically identified S. aureus (100%) as well as the mecA gene in all strains phenotypically resistant to methicillin (100%) . Moreover, it could detect the mecA gene in 8 strains (6%) phenotypically sensitive to methicillin. Only 18 strains (13.33%) recovered from skin and soft tissue infections were positive for PVL and (SCCmec) type IV. The results of this study indicate that the incidence of patients with CA-MRSA disease had been increased in Riyadh, KSA.[...] Read More.
Keywords: Staphylococcus aureus, CA-MRSA, PVL gene, multiplex polymerase chain reaction.
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Full Length Research Paper
Abstract: The amylase family of enzymes is a great significance due to its wide area of potential application. α-amylase from PENICILLIUM CAMEMBERTI PL21 obtained from I. N. A. (The Technological Laboratory of Agriculture National Institute Paris- France) and using orange waste as substrates was produced under optimum conditions, after 168 h of incubation and subjected for purification and characterization. The enzyme was purified by ammonium sulfate precipitation, dialysis, sephadex G-100 and DEAE-Sepharose CL-6B column chromatography. A trial for the purification of α-amylase resulted in an enzyme with specific activity of (154.2 units/ml/mg protein) with (38.5 folds) purification .The α-amylase activity increased by enzyme concentration rise. The optimum substrate concentration for soluble starch was 1 % (w/v) while the optimum incubation temperature was 30ºC. The purified α-amylase enzyme had a maximum activity at pH 6 and the Km value for soluble starch was 0.92 mg/ml. Analyses of this enzyme for molecular mass was carried out by SDS-PAGE electrophoresis, which revealed one band 60.5 Kda.[...] Read More.
Keywords: Penicillium camemberti PL21, α-amylase, purification, SDS-PAGE electrophoresis.
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Okonji Raphael Emuebie*, Popoola Michael Olaoluwa, Kuku Adenike and Aladesanmi Omolara Titilayo
Abstract: The cyanide metabolising enzymes (rhodanese and mercaptopyruvate sulphurtransferase) were estimated in different tissues of three species of tilapia (Tilapia zilli, Sarotherodon galileus, and Oreochromis niloticus) from two locations (Aiba and Osinmo reservoirs, both in the South-Western region of Nigeria). The enzyme activities were carried out by measuring the amount of thiocyanate produced by the two enzymes using specific substrates in each case. There was no significant difference in the activity of rhodanese in the tissues of the tilapia species from Aiba River. Mercaptopyruvate sulphurtransferase (3-MST) presented a different pattern of distribution with significant difference in the gut of the tilapia species. The study showed the activities of two cyanide detoxifying enzymes (rhodanese and mercaptopyruvate sulphurtransferase) in the different tilapia species indicating the presence of strong cyanide detoxifying mechanisms.[...] Read More.
Keywords: Rhodanese, mercaptopyruvate sulphurtransferase, cyanide, tilapia, detoxification.
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G. S. El-Baroty, H. H. Abd El-Baky, R. S. Farag and M. A. Saleh
Abstract: Essential oils obtained from the bark of Cinnamomum zeylanicum (cinnamon) and the rhizomes of Zingiber officinale (ginger) were characterized by analytical TLC and GC/MS, and their antimicrobial and antioxidant compounds were detected by TLC-bio-autography assays. Essential oil of cinnamon bark (CEO) was found to be a unique aromatic monoterpene-rich natural source, with trans-cinnamaldehyde (45.62%) as the major constituents. Ginger oil (GEO) was characterized by high content of sesquiterpene hydrocarbons, including β-sesquiphellandrene (27.16%), caryophyllene (15.29%), zingiberene (13.97%), α-farnesene (10.52%) and ar-curcumin (6.62%). CEO and GEO oils showed significant inhibitory activity against selected strains of bacteria and pathogenic fungi, with MIC values ranging from 20 to 120 µg/ml depending upon the microbial species. Cinnamaldehyde (CA) and eugenol in cinnamon bark oil and β-sesquiphellandrene, caryophyllene and zingiberene in ginger rhizome oil were identified as the most active antibacterial components, with the aid of bioautography on TLC and GC-MS. Also, both oil exhibited appreciable in vitro antioxidant activity as assessed by 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and β-carotene bleaching methods, compared to α-tocopherol, BHT and BHA. Guided isolation through TLC-autography using 0.05% DPPH and β-carotene/linoleic acid as a detection reagent led to identified CA and eugenol as main active antioxidant compounds in CEO. The significant antimicrobial and antioxidant activities of both oils suggest that it could serve as a source of compounds with preservative phenomenon.[...] Read More.
Keywords: Antimicrobial, bioautographic assay, antioxidant, essential oils, ginger, cinnamon.
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Full Length Research Paper
Abstract: Malate dehydrogenase was isolated and partially purified from blood stream TRYPANOSOMA VIVAX. The enzyme exists in isoenzyme forms (MDH1 and MDH2). The relative molecular weights of MDH1 and MDH2 determined by Sodium dodecyl sulphate polyacrylamide gel electrophoresis were 61 and 63 kdal. respectively. MDH2 lost activity immediately after purification. It has purification fold of 15 and percentage recovery of 31%. Similarly, MDH1 was purified 21 fold from the crude with 54% recovery. This isoenzyme was considerably stable. There was no MDH activity when the live parasites were incubated with the assay medium suggesting that the enzyme was not secreted by parasites. However, addition of detergent led to a surge in MDH activity suggesting that the enzyme is membrane bound. Malate dehydrogenase from the infective form of T. VIVAX has a stable and non – stable isoforms.[...] Read More.
Keywords: Malate dehydrogenase, isoenzyme, parasites, Trypanosoma vivax.
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Gloria A. Otunola*, Oyelola B. Oloyede, Adenike T. Oladiji and Anthony A. Afolayan
Abstract: The effects of a high dietary soybean oil and cholesterol on serum total cholesterol, low density lipoprotein (LDL-C), high density lipoprotein (HDL-C), and triglycerides were investigated. Total protein, albumin, glucose, gamma glutamyl transferase (GGT), aspartate aminotransferase (AST) and alanine amino transferase (ALT) activities were also investigated in weanling female Wistar rats for eight weeks. Two groups of weanling Wistar rats were use in this study. The first group of rats were fed with a control diet made up of the normal rat chow (C), while the second group was given a hypercholesterolemic diet (HPC) enriched with 25% soybean oil and 1% cholesterol for eight weeks. The dietary intake of the HPC diet significantly increased the level of total cholesterol, LDL-C and triglycerides in the serum of animals fed the (HPC) diet. GGT, AST and ALT activities were also markedly elevated in rats fed with the HPC diet. While total protein and glucose level of the animals fed with the HPC diet was remarkably reduced, there was no significant difference in the HDL-C and albumin contents of both groups. This study established that hypercholesterolemia is induced by high soybean oil/cholesterol diet, despite the fact that soybean oil has high content of poly unsaturated fatty acids. Also, the HPC diet led to weight loss in the rats and injury to both heart and liver of the rats.[...] Read More.
Keywords: Diet-induced, injury, lipid profile, enzyme activities, hypercholesterolemia, soybean oil, cholesterol.
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P. Praveen Kumar*, S. Kumaravel and C. Lalitha
Abstract: The present study was carried out for identification of the phytochemicals present in the Vitex negundo leaves and also evaluate the total phenols, total flavonoids and antioxidant activity of the leaf extract. Total phenols was carried out by Folin Ciocalteu method and the phenolic content was 27.72 mg/100 of gallic acid equivalent (GE). Antioxidant activity was evaluated by DPPH method and the leaves of V. negundo showed 23.21 mg/100 of Ascorbic acid Equivalent Antioxidant Capacity (AEAC). The GC-MS study also carried out and it showed the presence of phytochemicals like 4H-Pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl-(RT:6.17), Phytol (RT:19.67) and Vitamin E (RT:25.11).[...] Read More.
Keywords: Total Phenols, total flavonoids, antioxidant activity, DPPH, GC-MS.
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Munish Garg*, Chanchal Garg, V. J. Dhar and A. N. Kalia
Abstract: Alcoholic extract of Phyllanthus fraternus Webster whole plant (PFAE) prepared by successive solvent treatment was administered at a dose of 500 mg/kg body weight once in a day for 21 days to the alloxan induced diabetic albino rats. Certain biochemical parameters that is lipid profile (total cholesterol, high density lipoprotein, triacylglycerols), kidney functions (urea, creatinine) and liver functions (alkaline phosphate, alanine aminotransferase, aspartate aminotransferase) were evaluated and compared with normal and standard drug tolbutamide (200 mg/kg body weight) administered group. As a result, drug treatment has significantly improved the disturbed biochemical parameters at variable degrees when compared with standard drug. The phytochemical studies conducted for standardization of the extract showed the presence of tannins and flavonoids as major phytoconstituents. The total phenolics content was found to be 37.51 mg/g of drug extract. Quantitative estimation carried out on two major flavonoids by HPTLC confirmed a concentration of 1.706% w/w rutin and 5.614% w/w of quercetin present in the alcoholic extract. In conclusion, owing to the positive potential activity against disturbed biochemical parameters associated with diabetes, P. fraternus can be used effectively in the management of this deadly disease.[...] Read More.
Keywords: Phyllanthus fraternus, renal functions, liver functions tests, lipid profile, total phenolics.
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Full Length Research Paper
Abstract: ARTEMISIA ANNUA L. is a medicinal plant whose derivatives are used in the treatment of malaria. Phytochemical screening and histopathological effects of single acute intraperitoneal dose of the alcoholic extract of A. ANNUA, were investigated in Wistar rats in this study. Thirty five adult albino Wistar rats (109 - 307 g) of both sexes used for the study were randomly assigned on the basis of weight and litter origin into seven study groups of five rats per group. The control (group A) was administered placebo (2 ml of pure olive oil) while test groups B to G received single graded doses of 0.18, 0.35, 0.52, 0.70, 0.86 and 1.05 g/kg body weight of extract in olive oil vehicle, respectively. Twenty four hours after the single acute dose administration, animals were sacrificed and testes and ovary tissues obtained for histological evaluation using standard methods. Results of phytochemistry of the alcoholic extract assessed by standard methods identified the presence of alkaloids, glycosides (presence of these in A. ANNUA is questionable), flavonoids, reducing compounds and polyphenols present in different concentrations. Histopathological changes showed adverse lesions on the ovary ranging from atretic-degenerating corpus luteum, with loss of connective substance, arrest of ovarian follicle maturation to complete absence of ovarian follicle. No adverse histopathological changes were observed in the testes. The result suggests arrest of ovulation and a predisposition to infertility (add in the female animals). The possible roles of phytoestrogenic constituents in the favonoid fraction of the phytochemicals are discussed.[...] Read More.
Keywords: Artemisia annua, phytochemistry, histopathology, testes and ovaries.
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