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关键词： Atlantic cod   Fatty acids   Condition   Trophic niche   Greenland  

摘要： Body condition and energy reserves are important indicators of organism health, habitat suitability and predictors for the reproductive success in fish. In Greenland waters, Atlantic cod (Gadus morhua) inhabits different habitats in shallow and deep parts on top of the shelf and along slopes, where diet composition differs. We investigated the influence of habitat heterogeneity and trophic niche on body condition using organosomatic indicators, e.g. the morphometric index K, hepatosomatic and gonadosomatic indices, and biochemical indicators, e.g. lipid content and fatty acid compositions, of mature female cod. Body condition differed between sites and peaked in north-eastern regions in depths below 300 m towards the slope of the northern Irminger Sea. Trophic niches as indicated by stable isotope values and stomach composition data varied between sites, which was likely related to depth and differences between benthic and pelagic feeding regimes. Total lipid content and fatty acid profiles important for reproduction were associated with a pelagic diet comprised of mesopelagic fish and crustaceans. Interestingly, consumption of capelin was not linked to highest energy reserves as indicated by traditional body condition indices, such as K and the hepatosomatic index, but lowest ratios of eicosapentaenoic acid to arachidonic acid in gonads, which are known to be beneficial for high egg production. This shows that body condition on biochemical level can differ from conventionally used indices, which emphasizes the need to take fatty acid composition into account, when investigating condition and reproductive potential in cod. Our results emphasize that the factor habitat cannot be ignored for population replenishment of the cod stocks in Greenland waters and indicate that capelin as part of an Arcto-boreal diet benefits reproductive success in cod.

关键词： Enzymatic browning   Polyphenol oxidase   ATR-FTIR   Ascorbic acid   Salicylic acid  

摘要： The effect of ascorbic acid (AA) and salicylic acid (SA) used separately at the following concentrations 0.1, 0.2 and 0.3 %, on enzymatic browning and quality of "Nabout" dried fig during 6 weeks-storage at 4 degrees C within sealed polyethylene terephthalate (PET) bags, was investigated. The results showed that AA and SA at higher concentrations, particularly at 0.3 %, lowered the browning index compared to the control by 55 and 54 % respectively. The same dose suppressed samples polyphenoloxidase (PPO) to 75 and 80 %, respectively, compared to other concentrations. Both treatments showed a significant impact (p < 0.05) on dried figs quality by lowering the total phenols and antioxidant capacity loss during storage period. This trend was significantly important when the concentration applied was maximum (0.3 %). The same pattern was observed using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) technique, that showed a decreasing absorbance and integrated intensity around the vibration region of 1175-940 cm-1. This tendency was also depressed with the increase of anti-browning agents' concentration. High concentrations of AA (0.3 %) and SA (0.3 %), separately, minimized the overlapping in this region, showing high integrated intensities compared to other concentrations. In conclusion, the pre-storage application either of AA or SA at 0.3 % on dried figs could be appropriate to delay enzymatic browning and quality loss and therefore to extend their shelf-life.

关键词： Dietary total antioxidant capacity   Dietary phytochemical intake   Dietary inflammatory index   Patients with morbid obesity   Bariatric surgery   Anthropometric   Biochemical  

摘要： Background The present study aimed to assess dietary total antioxidant capacity (TAC), dietary phytochemical intake (PI), and dietary inflammatory index (DII) in patients with morbid obesity who are candidates of bariatric surgery and their association with anthropometric and biochemical parameters. Methods and Materials One hundred seventy patients with morbid obesity who were referred to surgery clinic of Firoozgar Hospital were enrolled in the study. Ideal body weight and adjusted ideal body weight were calculated. The dietary data were collected using a food frequency questionnaire. Anthropometrics and biochemical parameters were assessed. A p-value of <0.05 was considered significant. Results The strongest correlations of DII with dietary intakes and anthropometric and biochemical biomarkers were found for iron (p<0.0001). Significant association was also observed for ferritin (p=0.02) and transferrin (p=0.02). In terms of PI, The strongest associations were also found for iron (p<0.0001). Additionally, the value of body mass index (BMI) showed significant correlation with PI (p=0.04). The correlations of dietary total antioxidant indices with dietary intakes and anthropometric and biochemical biomarkers were assessed. Non-significant correlation was found between fasting blood sugar (FBS), hemoglobin A1C (HbA1C), vitamin B12, and vitamin D3 with ORAC index. Significant strong correlation showed for the value of iron in both ferric reducing ability of plasma (FRAP) and Oxygen Radical Absorbance Capacity (ORAC) indices (p<0.0001). Conclusion We find statistical significance correlation for dietary PI and BMI. The inflammatory and antioxidant properties of diet were not related to biochemical markers associated with obesity.

关键词： Crabs   Vitamin   Amino acids   Fatty acids   Nutrients   Proximate composition  

摘要： The commercially important edible crab species from Pakistani waters are Portunus pelagicus, Portunus sanguinolentus, Scylla serrata and Charybdis feriatus. The present study has been designed to investigate the nutritional composition of edible crab species including proximate composition, vitamins, minerals and amino acids content. Among all the species, fat content were found at low levels (0.25 %-1.86 %), however, the protein content was higher in hard shell crab (S. serrata), i.e. 23.3 %, than those in soft shell crabs (P. pelagicus, P. sanguinolentus and C. feriatus), 16.4 %, 14.2 % and 15.1 %, respectively. Energy value was high in S. serrata (107 kcals/100 g) whereas C. feriatus recorded the lowest value (65.5 kcals/100 g). In terms of amino acid profiling a total of eighteen amino acids were detected from which arginine (19.0 mg/100 g in S. serrata and 9.98 mg/100 g in P. sanguinolentus) and lysine (0.15-6.53 mg/100 g) have shown the highest values with variations in all crab samples. Of the seven minerals examined, calcium was the highest ranging between 292 ppm and 513 ppm followed by zinc (15.7 ppm-47.4 ppm) in all four crab species. Among the vitamins, niacin (Vit B3) recorded the highest value ranging between 16.9 mg/100 g and 49.2 mg/100 g followed by thiamine (Vit B1) and ascorbic acid (Vit C) in all crab samples. The results showed that the crabs contained appreciable amounts of nutrients. The present study findings revealed that the mud crab S. serrata has higher values of nutrients in terms of protein, amino acids, vitamins and minerals than other species.

关键词： Myxococcus sp   strain V11   Trehalose synthase   Enzymatic properties   Site-directed mutagenesis  

摘要： The tresI gene of Myxococcus sp. strain V11 was cloned, and found to encode a trehalose synthase comprising 551 amino acids. The deduced molecular weight of the encoded TreS I protein 64.7 kDa and the isoelectric point (pI) was predicted to be 5.6. The catalytic cleft consists of the Asp202-Glu244-Asp310 catalytic triad and additional conserved residues. The recombinant (His)6-tag enzyme was expressed in Escherichia coli BL21(DE3) and purified by Ni2+-affinity chromatography, resulting in a specific activity of up to 172.7 U/mg. TLC and HPLC results confirmed that rTreS I can convert maltose into trehalose, with a yield of 61%. The KM and Vmax values of recombinant TreS I for maltose were 0.62 mM and 25.5 mM min? 1 mg? 1 protein, respectively. TreS I was optimally active at 35? and stable at temperatures of <25 ?C. TreS I was stable within a narrow range of pH values, from 6.0 to 7.0. The enzymatic activity was slightly stimulated by Mg2+ and strongly inhibited by Fe3+, Co2+ and Cu2+. TreS I was also strongly inhibited by SDS and weakly by EDTA and TritonX-100.

关键词： Diesel exhaust particles   Naringenin   Oxidative stress   Inflammation   Heart   Aorta  

摘要： Studies have shown that diesel exhaust particle (DEP), a typical air particulate matter (PM) component of diesel exhaust, exerts its toxic effects by inducing oxidative and pro-inflammatory effects. Naringenin is the predominant flavanone in citrus fruits and has been reported to possess antioxidant, anti-inflammatory, anti-carcinogenic, and anti-mutagenic effects. This study examined the effects of naringenin on the oxidative and inflammatory effects of DEP in aorta and heart of Wistar rats. Diesel exhaust particle collected from a vehicular source in Akure, Nigeria, was extracted in methanol, fractionated and characterized by GCMS. Forty male Wistar rats (80-90 g) were divided into 8 groups. These rats were exposed to either methanol extract of SRM 2975 (mSRM;0.064 mg/kg) DEP or collected diesel exhaust particles (mDEP;0.064 or 0.64 mg/kg) sample in the presence or absence of naringenin (50 mg/kg). Both the DEP extracts and naringenin (NAR) were administered by oral gavage. The molecular interactions of NAR with target proteins associated with DEP toxicity were determined using in silico approach. The results show that both mDEP and mSRM caused significant (p < 0.001) decrease in serum HDL but increase serum AST/ALT ratio, ALP, LDL, triacylglycerol (TG), total cholesterol (TC), tissue conjugated dienes (CD) and MDA levels. The extracts also significantly (p < 0.001) increased the expression of IL-1 beta, TNF alpha, NF-kappa B, I kappa B, and I kappa KB in the aorta and heart, but decreased Nrf2, HO1, and anti-inflammatory IL-10 mRNA levels when compared with control. Pretreatment with NAR significantly (p < 0.001) reversed all these DEP-induced effects in both tissues. In conclusion, naringenin has the potential to mitigate DEP-induced oxidative stress and inflammation and thus may serve as a therapeutic agent against air pollution-induced cardiovascular damage.

关键词： Contaminants   Amphibians   Morphology   Oxidative stress   Enzymes  

摘要： Lithobates catesbeianus tadpoles were exposed for 96 h to water from two sites of the Sorocaba River (summer and winter), Ibiuna (PI) and Itupararanga reservoir (PIR) that contained metals. In the liver, in PI, the glutathione peroxidase (GPx) decreased, and the glutathione S-transferase (GST) and carbonyl proteins (PCO) increased. In PIR, the glutathione reduced (GSH) increased, while there was a decrease in catalase (CAT), GPx, GST, PCO, and superoxide dismutase (SOD). In winter, GPx and GST increased in both points. Regarding the kidneys, lipoperoxidation (LPO) levels and GST decreased, while GSH increased in the summer. In the winter, LPO increased in PI. In the muscle, in the summer, there was an increase in GSH and GST and change in PCO. In the winter, the levels of PCO increased and CAT decreased in PIR. The area and volume of the hepatocyte and nucleus area increased in the summer and decreased in the winter. Hepatic melanin decreased in the summer after exposure to PIR water. There were the systemic effects of Sorocaba River water exposure at different times of the year with alterations in biomarkers at different levels, in which kidney shows highest Integrated Response of Biomarkers (IBR) value followed by liver and muscle. Biochemical biomarkers were more sensitive than morphological ones. The more sensitive biochemical markers were MT, PCO, GST and LPO. These effects confirm the hypothesis of metabolic alteration in bullfrog tadpoles by the Sorocaba River water. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Actinomadura   Keratinases   Catalytic activity   Keratin-containing wastes   Leather processing industry  

摘要： Two novel extracellular keratinases were produced by Actinomadura keratinilytica strain Cpt20. Both enzymes were purified to homogeneity using heat-treatment (60 degrees C for 30 min) and ammonium sulfate salt fractionation (40 %-70 %), followed by anion-exchange chromatography with fast protein liquid chromatography (FPLC) system. The purified keratinases, designated as KERA-71 and KERB-19, are monomeric and named according to their molecular masses of 71 kDa and 19 kDa, respectively, as estimated via sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), zymography, and high-performance liquid chromatography (HPLC). N-terminal residues of both enzymes exhibited high identity with other Actinomadura keratinases. Their hydrolytic activities were significantly inhibited by phenylmethylsulfonyl fluoride (PMSF) and di-iodopropyl fluorophosphates (DFP), classifying them in the serine proteases family. While KERA-71 was ideally active at 50 degrees C and pH 8, KERB-19 illustrated optimum activity at 40 degrees C and pH 7. The thermo-activity and thermo-stability of both enzymes were improved with 10 mM Ca2+. Interestingly, the KERA-71 displayed broader substrate specificity, higher catalytic efficiency (kcat/Km), and a high degree of hydrolysis (DH) than actinobacterial keratinases, including KERB-19, KERDZ, KERAK-29, Actinase E, and KERAB. Interestingly, both enzymes exhibited effective keratinase activities with high potential, illustrating their possibility to be used in the process of keratincontaining wastes valorization and leather industry.

关键词： Bacteriophage   Lysins   CBD   Crystal structure  

摘要： Lysins are a class of hydrolytic enzymes used by bacteriophages to target and cleave the peptidoglycan of bacterial cell walls during their lytic cycle. The lysins from bacteriophages that infect Gram-positive bacteria are typically monomeric and consist of one or two catalytic domains (CD) and a cell binding domain (CBD). However, multimeric lysins encoded by a single gene have also been reported, among which Lys170 from enterococcal phage F170/08 was one of the first identified. Here, we determined the crystal structure of Lys170 CBD at 1.40 angstrom resolution. The structure reveals that Lys170 CBDs assemble into a tetrameric functional unit and that each monomer folds into a three-stranded beta-sheet core capped on each side by an alpha-helix. In addition, we identified key residues of Lys170 CBD involved in host cell binding. Our work provides a basis for designing highly efficient lysins targeting Enterococcus faecalis.