Agro-waste derived compounds (flax and black seed peels): Toxicological effect against the West Nile virus vector,Culex pipiens L. with special reference to GC–MS analysis

The development of different approaches to use agricultural residues as a source of high value-added products, become a must, especially after the problems emerged due to their accumulation. This contribution demonstrates the potential of agricultural residues, Linuim usitatissium (flax seed) and Nigella sativa (black seed) peels, as raw materials for the production of bioactive products, botanical insecticides, against Cx. pipiens, with deep analysis to their chemical constituents by gas chromatography-mass spectrometry, the larvicidal efficacies of the three crude extracts (methylene chloride, petroleum ether and methanol 70%) from the two plant waste peels were evaluated for the first time against the late third instar larvae of Cx. pipiens. Results indicated different lethal doses in larvae depending on the efficacy of organic solvent used. For both compounds methanol 70% extracts produced the highest dry yield. The most efficient solvent is petroleum ether in case of both flax and Black seed peels. Petroleum ether extract exhibited the highest toxicity against Cx. pipiens with an LC50 of 69.6383 ppm. The same results for black seed indicated that petroleum ether was the most efficient against Cx. pipiens with an LC50 of 40.7748 ppm. The study revealed for the first time the type of phytochemical constituents presents in peels of flax and black seeds using GC–MS analysis which revealed twenty-eight constituents among extracts of flax and black seed peels ranging from to 58.8711% to 99.99% of the total extracts. GC–MS profiling showed that a five constituents, 9-2-Methyl-Z, Z-3, 13 octadecadienol (terpenoid), 9,17-Octadecadienal, (Z)-, Nonanoic acid, 9-oxo-, methyl ester, 9,12-Octadecadienoic acid Z,Z and Octasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecamethyl- have insecticidal activity beside many other biological activities as recorded from a variety of botanical extracts. While the constituents like Hexadecanoic acid, methyl ester and cis-9-Hexadecenal, both of them are larvicidal, cis-Vaccenic acid and 9-Oxononanoic acid showing only an insecticidal activity beside Undecanoic acid the mosquito repellent. The other six constituents Linoelaidic acid, Oleic Acid, Z-2-Octadecen-1-ol, 1-Methoxy-3-hydroxymethylheptane, Cis-11,14–Eicosadieonic acid-methyl ester and Heptasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13-tetradecamethyl- are constituents of other plant extracts which showed as a whole an insecticidal activity.     

Isolation and characterization of raw heparin from dromedary intestine: evaluation of a new source of pharmaceutical heparin

Heparin, a heterogeneous anionic polysaccharide, is the glycosaminoglycan (GAG) used clinically an anticoagulant. This anticoagulant activity is primarily derived from its binding to the serine protease inhibitor antithrombin III, a potent inhibitor of thrombin (factor IIa) and factor Xa. Heparin is a complex natural product and its in vitro synthesis is not yet possible due to the difficulty of organizing the many biosynthetic enzymes required for its synthesis. The principle natural sources for heparin include porcine intestine and bovine lung. These two sources pose concerns for religious and health reasons, respectively. To circumvent these concerns, GAG from the intestinal tissue of one humped camel was isolated. Chemical characterization of this newly isolated GAG and spectroscopic analysis by 1D and 2D 1H-NMR were undertaken. Unsaturated disaccharide compositional analysis was performed on the enzymatically depolymerized GAG and the molecular weight of the isolated GAG was determined by gradient polyacrylamide gel electrophoresis. Anticoagulant activity of the newly isolated GAG was tested by using an anti-factor Xa assay. The results of these studies suggest that the GAG from one humped camel intestine is a mixture of heparin and heparan sulfate and represents an alternative source of heparin.     

Improved rapid sampling for in vivo kinetics of intracellular metabolites in Saccharomyces cerevisiae.

An integrated approach is used to develop a rapid sampling strategy for the quantitative analysis of in vivo kinetic behavior based on measured concentrations of intracellular metabolites in Saccharomyces cerevisiae. Emphasis is laid on small sample sizes during sampling and analysis. Subsecond residence times are accomplished by minimizing the dead volume of the sterile sampling system and by maximizing flow rates through application of vacuum to the sampling tubes in addition to the overpressure in the fermenter. A specially designed sample tube adapter facilitates sampling intervals of 4 to 5 s for various test tube types. Statistical analysis of the results obtained from enzymatic and liquid chromatography mass spectrometry (LC-MSMS) analysis of the metabolite concentrations was used to optimize the sampling protocol. The most notable improvement is reached through the introduction of vacuum drying of the cell extract. The presented system is capable of reliably dealing with fermenter samples as small as 1-g with a variation of less than 3%, and is thus ideally suited for intracellular measurements on small, lab-scale fermenters.     

Chemical Characterization,Antioxidant, Antimicrobial,Cytotoxicity and in Silico Studies of Hexane Extract and Essential Oils from Citrus limon Leaves

The present study investigates the chemical composition, antioxidant and antimicrobial bioactivities of essential oil and hexane extract from Citrus limon leaves. The isolation of essential oil was carried out using the Clevenger apparatus. The percentage yield of essential oil and hexane extract from Citrus limon leaves was 0.59 and 0.50 %, respectively. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay highlighted that Citrus limon leaves essential oil (CLEO) and hexane extract exhibited the significant antioxidant potential of 69.64 and 67.55 %, respectively, compared to the BHT standard. Similarly, a significant inhibition in linoleic acid peroxidation was recorded in both CLEO (81.93 %) and hexane extract (50.34 %). Characterization of chemical constituents in CLEO and extract was executed using GC/MS, where Limonene was detected as a major compound in CLEO (60.52 %) and hexane extract (73.62 %). The haemolytic activity ranged from 2.46 to 5.75 % revealing negligible cytotoxicity of CLEO and hexane extract. In silico studies agree with the in vitro antimicrobial studies, where vinimalol, taraxasterol, and moretenol present in CLEO showed strong interactions/inhibition against dihydroorotase and DNA gyrase from E. coli, and the tyrosyl-tRNA synthetase and DNA gyrase from S. aureus. Based on the current data, it may be concluded that both CLEO and hexane extract possessed significant bioactivities, such as antimicrobial and antioxidant activity, with minimal cytotoxicity.     

Synthesis and Characterization of New Lutidinium Ionic Liquid-Supported Vanadylsalicylaldoxime Complex for Catalytic Application in Epoxidation Reaction

A new chelating task-specific ionic liquid (TSIL), lutidinium-based salicylaldoxime ( LSOH ), and its square pyramidal vanadyl(II) complex (VO(LSO)₂) have been successfully synthesized and structurally characterized using elemental (CHN), spectral, and thermal analyses. The catalytic activity of the lutidinium-salicylaldoxime complex (VO(LSO)₂) in the alkene epoxidation reactions was studied under various reaction conditions, such as solvent effect, alkene/oxidant molar ratio, pH, reaction temperature, reaction time, and the catalyst dose. The results demonstrated that the CHCl₃ solvent, 1 : 3 of the cyclohexene/H₂O₂ ratio, pH 8, temperature of 340 K, and catalyst dose of 0.012 mmol are assigned as the optimum conditions for achieving maximum catalytic activity for VO(LSO)₂. Moreover, the VO(LSO)₂ complex has the potential for application in the effective and selective epoxidation of alkenes. Notably, under optimal VO(LSO)₂ conditions, cyclic alkenes convert more efficiently to their corresponding epoxides than linear alkenes.     

The possible alleviating effect of garlic supplement on the neural retina in a rat model of hypercholesterolemia: A histological and immunohistochemical study

The purpose of this work was to prove that oxidative stress is the main mechanism responsible for retinal neurodegenerative changes, subsequent apoptosis, and inflammatory cytokine release in rats fed with a high cholesterol diet (HCD) and determine the role of garlic in alleviating these changes. Forty rats were equally divided into four groups: control, garlic-treated (positive control), HCD, and HCD + garlic-treated (HCD + G). By the end of the experiment (24 weeks) blood samples were collected for assessment of serum lipid profile, oxidative stress parameters, and plasma levels of IL-6 and TNF-α. Both eyes of the rats were enucleated; one was used for light microscopic examination and the other for electron microscopic examination. There was a significant increase in the levels of serum lipids, oxidative stress parameters, IL-6 and TNF-α, and area of expression of caspase-3 in the HCD group compared to both the control and HCD + G groups. Histological examination revealed degenerative changes in all layers of the neural retina in the HCD group. Garlic administration resulted in a significant improvement in the biochemical, immunohistochemical, and histological characteristics of hypercholesterolemic rats. These findings support the hypotheses that garlic has strong antioxidant, anti-apoptotic, and anti-inflammatory properties. Garlic ameliorates the neurodegenerative changes in the neural retina of hypercholesteremic rats.Key words: Hypercholesterolemia, garlic, neural retina     

Ultrasensitive Norovirus Detection Using DNA Aptasensor Technology

DNA aptamers were developed against murine norovirus (MNV) using SELEX (Systematic Evolution of Ligands by EXponential enrichment). Nine rounds of SELEX led to the discovery of AG3, a promising aptamer with very high affinity for MNV as well as for lab-synthesized capsids of a common human norovirus (HuNoV) outbreak strain (GII.3). Using fluorescence anisotropy, AG3 was found to bind with MNV with affinity in the low picomolar range. The aptamer could cross-react with HuNoV though it was selected against MNV. As compared to a non-specific DNA control sequence, the norovirus-binding affinity of AG3 was about a million-fold higher. In further tests, the aptamer also showed nearly a million-fold higher affinity for the noroviruses than for the feline calicivirus (FCV), a virus similar in size and structure to noroviruses. AG3 was incorporated into a simple electrochemical sensor using a gold nanoparticle-modified screen-printed carbon electrode (GNPs-SPCE). The aptasensor could detect MNV with a limit of detection of approximately 180 virus particles, for possible on-site applications. The lead aptamer candidate and the aptasensor platform show promise for the rapid detection and identification of noroviruses in environmental and clinical samples.     

Nuclear factor-kappaB inhibition by pyrrolidinedithiocarbamate attenuates gastric ischemia-reperfusion injury in rats

Pyrrolidinedithiocarbamate (PDTC) is a potent antioxidant and an inhibitor of nuclear factor-kappaB (NF-kappaB). The present study examined the impact of PDTC preconditioning on gastric protection in response to ischemia-reperfusion (I/R) injury to the rat stomach. Male Wistar rats were recruited and divided into 3 groups (n = 7). One group was subjected to gastric ischemia for 30 min and reperfusion for 1 hour. The second group of rats was preconditioned with PDTC (200 mg/kg body mass i.v.) 15 min prior to ischemia and before reperfusion. The third group of rats was sham-operated and served as the control group. Gastric I/R injury increased serum lactate dehydrogenase level, vascular permeability of gastric mucosa (as indicated by Evans blue dye extravasation) and gastric content of inflammatory cytokine; tumor necrosis factor-alpha (TNF-alpha). Moreover, oxidative stress was increased as indicated by elevated lipid peroxides formation (measured as thiobarbituric acid reactive substances) and depleted reduced glutathione in gastric tissues. NF-kappaB translocation was also detected by electrophoretic mobility shift assay. Microscopically, gastric tissues subjected to I/R injury showed ulceration, hemorrhages, and neutrophil infiltration. Immunohistochemical studies of gastric sections revealed increased expression of p53 and Bcl-2 proteins. PDTC pretreatment reduced Evans blue extravasation, serum lactate dehydrogenase levels, gastric TNF-alpha levels, and thiobarbituric acid reactive substances content, and increased gastric glutathione content. Moreover, PDTC pretreatment abolished p53 expression and inhibited NF-kappaB translocation. Finally, histopathological changes were nearly restored by PDTC pretreatment. These results clearly demonstrate that NF-kappaB activation and pro-apoptotic protein p53 induction are involved in gastric I/R injury. PDTC protects against gastric I/R injury by an antioxidant, NF-kappaB inhibition, and by reduction of pro-apoptotic protein p53 expression, which seems to be downstream to NF-kappaB, thus promoting cell survival.