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Abstract

The present work examines the influence of the leaching conditions on the release of various chemical elements from a cementitious material obtained by solidification of an industrial waste rejection of Algeria. Toxicity Characteristic Leaching Procedure (TCLP), X-ray diffraction (XRD) and Scanning electron microscopy coupled with energy dispersive X-ray microanalysis SEM-EDX analyses were employed to characterize the waste and the stabilized/solidified materials. Than several formulations were prepared with different percent of waste ranging from 0 % to 30 %. To evaluate the influence of leaching conditions on the release of chemical ions (Zn2+, Pb2+, Cl-, Mg2+, Ca2+, Na+, K+ and SO4 2−) contained in the stabilized and solidified materials, the Acid Neutralization Capacity (ANC), the Pore Water (PW) and Monolith Leaching Tests (MLT) have been carried out. The leaching tests (ANC, PW and MLT) have shown a low metal leachability. However, the lowest released amount was observed for the MLT.

Abstract

This study was conducted to identify the most deleterious nonsynonymous single nucleotide polymorphisms (nsSNPs) in the ovalbumin gene family, including OVALX, OVALY, and OVAL genes, which are involved in the synthesis of the most important components in the chickens’ eggs using a comprehensive in silico approach. Ten different computational servers were utilized to prioritize the possible deleterious effects of the retrieved nsSNPs in terms of structure, function, and stability. Results indicated entirely damaging effects of H365P in OVALX, I167T in OVALY, and V209G, L231P, F307C, and S317P in OVAL proteins. Further prediction tools showed that all of these deleterious nsSNPs were positioned in variable locations within several α-helix motifs in all studied ovalbumin proteins. Furthermore, all witnessed nsSNPs were predicted to be resided in the receptors binding sites, signifying remarkable involvement of such nsSNPs in damaging of the altered proteins. In conclusion, the present study provides the first inclusive data with regard to the most deleterious nsSNPs in OVALX, OVALY and OVAL genes in chickens. The present bioinformatics data may be useful for breeders who intend to raise chickens for egg production, in such a way the presence of any of these deleterious nsSNPs in any selected breed may possess several damaging effects on the egg components, which may impair egg production. Therefore, it can be stated that breeders have to confirm the absence of any of these deleterious nsSNPs before being proceeded further for large-scale egg-production purposes.

Abstract

Methylxanthines such as caffeine, theophylline, theobromine are significant and widespread psychoactive substances. We developed the isocratic method with optimum composition of the mobile phase 90 % water: 10 % acetonitrile and confirmed repeatability of retention times and peak areas. The developed HPLC method was applied to determine the content of methylxanthines in selected types of black and green teas available on the market. Of the black teas (tea bags), the highest concentration of theobromine was found in Ceylon tea (18.98 mg.L−1). The highest concentration of caffeine was in a cup of Earl Gray tea (254.09 mg.L−1). Among loose black teas, the highest content of both theobromine and caffeine was found in Pu Erh Superior tea, where the theobromine content was 24.62 mg.L−1 and the caffeine content was 520.67 mg.L−1. Of green powder teas, highest caffeine content (306.46 mg.L−1) was in Shizuoka Matcha Premium and the highest content of theobromine (8.45 mg.L−1) was found in GABA Midori. From the loose green tea, the highest concentration of theobromine (12.85 mg.L−1) was in Lung Ching West Lake. The highest caffeine content (484.85 mg.L−1) was in Gyokuro Shizuoka Premium Tea. In both types of teas the amount of theobromine and caffeine was quantified, but the presence of theophylline was not proven. Data on contents of these metabolites in tea products are highly informative for consumers.

Abstract

Testing microbial quality of the harvested rainwater remains a challenge in many countries. The H2S test kit is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. This study compares its efficiency with the standard indicators microorganisms in the detection of faecal contamination of rainwater in South Africa. A total of 88 rainwater samples were collected from various tanks in the Eastern Cape, South Africa over three months in 2016. The collected samples were analysed for faecal bacterial contamination using the H2S test kit, Colilert-18/Quanti-tray®/2000 and the membrane filtration technique for faecal coliforms (MFT). The correspondence rate of the H2S test kit with MFT was 88 %, while for the Colilert® it was 76 %. The H2S test kit confirmed faecal contamination when concentrations of standards indicators microorganisms were 5 most-probable number of cells/100 cm3 or higher. Overall, the best correspondence of the H2S test kit with Colilert® was observed at E. coli concentrations above 50 most-probable number of cells/100 cm3. Results of the H2S test kit correlated better with MTF, while the medium used has strongly influenced the enumeration of faecal contamination. Results point to strong effect of media used and revealed the need to calibrate the correspondence between the standard indicator microorganisms and the H2S test kit under local conditions for specific settings.

Abstract

Drug metabolism in liver microsomes was studied in vitro using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Relevant drug was incubated with dog, human and rat liver microsomes (DLMs, HLMs, RLMs) along with NADPH, and the reaction mixture was analyzed by LC-MS/MS to obtain specific metabolic profile. GRACE analytical C18 column, Vision HT (50 × 2 mm, 1.5 μm) was implemented with acetonitrile and water (+ 5 mM ammonium acetate) in a gradient mode as the mobile phase at a flow 0.4 mL.min−1. Different phase I and phase II metabolites were detected and structurally described. The metabolism of the studied drugs occurred via oxidation, hydroxylation and oxidative deamination processes. Conjugates with the glucuronic acid and sulfate were also observed as phase II biotransformation. The central composite design (CCD) showed that factors, such as time incubation, liver microsomal enzymes concentration and NADPH concentration, along with drying gas temperature, nebulizer gas pressure and capillary voltage significantly affected the final response of the method. This study describes the novel information about the chemical structure of the potential metabolites of selected biologically active compounds, which provide vital data for further pharmacokinetic and in vivo metabolism studies.

Abstract

The soil is a key component of natural ecosystems because environmental sustainability depends largely on a sustainable soil ecosystem. The objective of this study was to predict the impact of selected toxic compounds from dumpsite or contaminated soils on human health at the molecular level of biological processes. The in silico methods that were used include toxicokinetics and target gene prediction, molecular docking, and gene expressing network analysis. The result showed bisphenol A (BPA), 2,20-bis(p-chlorophenyl)-1,1-dichloroethane (DDD), 2,20-bis(p-chlorophenyl)-1,1-trichloroethane (DDT), diethylhexyl phthalate (DEHP), nonylphenol (NP) and tetrachlorodibenzodioxin (TCDD) as the active toxic compounds that can modulate biological system and are considered as potential cause of several diseases including cancer. The principal target genes include substance-P receptor (also known as Neurokinin 1 receptor), 5-hydroxytryptamine receptor, human serotonin transporter; estrogen receptor alpha; and aryl hydrocarbon receptor. These genes implicated SUZ12, STAT3, and TRIM28 as the major transcription factors while mitogen-activated protein kinases and cyclin-dependent kinases were the major kinases from the protein-protein interaction. All the six toxicants investigated showed good free binding energies (ΔG) which were below - 5.0 kcal.mol−1. These toxic compounds showed ligand efficiency greater than 0.25 kcal.mol−1. HA and would possibly cause fatal damage on human health. The order of in silico predicted toxicity of these compounds were BPA > DDD = DDT > TCDD > NP > DEHP. Our results identified potential threats, which the selected toxicants can pose to public health. More importantly, it provides basis for investigation of super bugs (microorganisms) that can remediate these toxicants in our environment. Environmental monitoring and modern wastes management system should be implemented and enforced in the affected countries in order to safeguard the health of the citizenry.

Abstract

Recombinant protein production in heterologous hosts often seems a simpler and more effective way than its production by natural producer. The secretion of recombinant protein in Escherichia coli has many advantages comparing to than in insect or mammalian cells. The important factor for high-level recombinant protein production is the sufficient amount of E. coli biomass. Therefore, the aim of this study was to optimize the composition of propagation medium resulting in the maximum biomass yield of recombinant E. coli as the part of fermentation strategy for neuraminidase (NA) production. Three independent variables including glucose, asparagine and phosphate concentrations, and four dependent variables, such as biomass yield, residual concentrations of glucose or asparagine and pH of the propagation medium after fermentation, were chosen to the optimization by Response Surface Methodology (RSM). The optimal conditions for the maximum biomass yield expressed as dry cell weight (DCW) (16.57±0.55 g DCW.L−1) were as follows: glucose concentration of 39.37 mM, asparagine concentration of 62.68 mM and phosphate concentration of 14.80 mM. For this model, the predicted values for the responses are close to the experimental values. The yield of desired pET15b-neu plasmid from E. coli cells cultivated in optimized propagation medium was almost 23 % higher than in commonly used Luria-Bertani (LB) medium suggesting that asparagine may be involved in the induction of plasmid amplification.

Abstract

Advances Polyphenol Oxidase (PPO) from Sorghum bicolor (white and yellow varieties) grains were investigated for optimum processing condition. The partially purified enzyme was obtained from two varieties of Sorghum bicolor by step-wise separation through ion-exchange and size-exclusion chromatography. The final purification gave a yield of 7.33 % and 12.3 % for PPO from white and yellow sorghum respectively. The PPO has Vmax and Km of 2.66 U.mL−1 and 19.72 mM for white sorghum, 1.33 U.mL−1 and 12.92 mM for yellow sorghum. The optimal pH of PPO activity was found at pH 4 and pH 7 for white and pH 4 and pH 8 for yellow sorghum. The pKa 7.4 and 8.7 were obtained for PPO from white sorghum, and pKa 5.4, 7.4 and 8.5 for yellow sorghum. The PPO residual activity were above 70 % at 5 hours of incubation within the neutral pH ranges for white sorghum, while those of yellow sorghum were below 40 %. The optimum temperature of 40 ºC and 30 ºC for white and yellow sorghum PPO respectively. The average value of enthalpy (ΔH), entropy (ΔS) and Gibbs free energy (ΔG) obtained at 20 min of incubation and temperature 50 – 80 °C were respectively 49.03 kJ.mol−1, - 129.52 J.mol−1.K−1, and 92.81 kJ.mol−1 for white sorghum PPO, and 90.1 kJ.mol−1, - 9.29 J.mol−1.K−1, and 93.37 kJ.mol−1 for yellow sorghum PPO. Zn2+, Fe2+ and ascorbic acid inhibited PPO while Cu2+, Na+ and K+ activated the enzyme. The results suggest the processing parameters for controlling PPO in potential industrial application of white and yellow sorghum grains.

Abstract

False flax (Camelina sativa L.) is currently under-exploited but highly promising oilseed crop. Combining Camelina’s attractive agronomic traits with its unprecedented ease for genetic engineering makes it an ideal plant chassis for biotechnology applications, in particular synthetic biology strategies. For targeted expression of transgene particularly to seeds requires identification and application of seed specific promoters. In the present study two cultivars of Camelina, namely Zuzana and Smilowska, were used for transformation at early flowering stage using the floral dip method. The plants were inoculated with Agrobacterium bearing a construct for expression of red fluorescent protein (RFP) under the control of the seed specific cruciferin promoter CRUC from Arabidopsis. Transgenic seeds and plants were identified on the basis of red fluorescence (RFP) and kanamycin resistance. Relatively high transformation efficiency of 8 % was achieved particularly for the cultivar Zuzana. However, many of regenerants exerted developmental deformations such as lack of shoot apical meristem, deformed or absent cotyledons, etc. Furthermore, the activity of the CRUC promoter was still active also in true leaves rendering this promoter as inappropriate for seed targeting of the transgene. Nevertheless, genetic transformation remains a tool for direct modulation of pathways for oil synthesis in oilseed crops.

Abstract

Nature and the environment are affected by various human industrial and/or urban discharges. Remediation for this problem requires first and foremost an in-depth analysis and an overall characterization of the intrinsic properties of the pollution-receiving environments. Secondly it is necessary to predict in these environments the behavior of dangerous chemical species (here particularly heavy metals) in the long term. This study focuses mainly on a detailed characterization of 4 soil samples sampled in vicinity of wild dump-BOULIMAT located 15 km west of the city of Bejaia-Algeria. The samples were characterised by atomic absorption spectrometry, X-ray diffraction, Fluorescence X and Infrared spectroscopy. The data showed high concentrations of metallic elements especially Zn (2,651.8 mg.kg−1) and Ni (163.44 mg.kg−1) in the soil samples. For their remediation, the stabilization/solidification (S/S) process with hydraulic binders appeared promising in reducing the polluting power of metal. This approach has considerably reduced the content of pollutants; 98 % removal was obtained for Ni and 99 % for Zn. The XRD analysis technique revealed the occurrence or absence of metallic elements in the crystallized phases.