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关键词： Crowding stress   Growth   Muscle quality   Hormone   Antioxidant capacity   TROUT ONCORHYNCHUS-MYKISS   BODY-COMPOSITION   IMMUNE-RESPONSE   COMMON CARP   QUALITY   CORTISOL   STRESS   METABOLISM   HISTOLOGY   SELENIUM  

摘要： This study investigated the effect of stocking density on growth performance, blood biochemical profiles, antioxidative capacity, and muscle quality of gibel carp (Carassius gibelio). Gibel carps (initial body weight 57.04 +/- 1.89 g) were reared at high stocking density (HSD, 10.85 kg m(-3)), medium stocking density (MSD, 5.06 kg m(-3)), and low stocking density (LSD, 1.47 kg m(-3)) for 60 days. The LSD group exhibited the highest growth rate, while HSD significantly inhibited fish growth. The muscular compositions of crude fat, crude ash, and moisture were significantly changed by stocking density, but crude protein content did not differ significantly. The stocking density altered the muscular texture profiles of gibel carp. Compared to either the HSD group or the MSD group, the highest levels of resilience and springiness occurred in the LSD group. Significant differences were observed in the levels of plasma glucose, alanine aminotransferase, aspartate aminotransferase, cholesterol, and creatinine among three groups. The fish exhibited the highest level of plasma cortisol as well as the lowest levels of triiodothyronine and thyroxine in the HSD group. The fish stocked in the LSD group showed the highest activities of superoxide dismutase, glutathione peroxidase, and catalase as well as the highest content of glutathione in liver. The significant highest total antioxidant capacity occurred in the fish stocked in the LSD group. The results showed that HSD resulted in chronic crowding stress, and exerted negative impact on growth performance, muscle quality, and antioxidative capacity of gibel carp.

关键词： Alkaloids   Antioxidant enzymes   Drought   Gene expression   Lipid peroxidation   Proline   INDUCED OXIDATIVE STRESS   POSTHARVEST QUALITY   ALKALOID BIOSYNTHESIS   EXOGENOUS APPLICATION   ANTIOXIDANT ACTIVITY   FOLIAR APPLICATION   HYDROGEN-PEROXIDE   INDOLE ALKALOIDS   WATER-STRESS   GROWTH  

摘要： Drought is a main abiotic stress that restricts plant growth and development. The increased global demand of anti-cancer alkaloids extracted from periwinkle (Catharanthus roseus) is mainly related to plant growth and development, which are severely affected by drought. Chitosan nanoparticles (CSNPs) have been used to boost plant growth and defense mechanism, however their impact to alleviate drought stress of C. roseus has not been investigated yet. In this study, control and stressed plants (100 and 50% of field capacity [FC], respectively) were subjected to CSNPs application at 1%. Drought stress considerably reduced plant growth, relative water content (RWC), stomatal conductance and total chlorophyll; however, CSNPs mitigated these effects. They enhanced proline accumulation and the activity of catalase (CAT) and ascorbate peroxidase (APX) with possible mitigation of drought-induced oxidative stress. Therefore, they reduced H2O2 and malondialdehyde (MDA) accumulation, and eventually preserved membrane integrity. Drought stress increased alkaloid accumulation, and further increase was observed with the application of CSNPs. High alkaloid content was associated with induced gene expression of strictosidine synthase (STR), deacetylvindoline-4-O-acetyltransferase (DAT), peroxidase 1 (PRX1) and geissoschizine synthase (GS) up to 5.6 folds under drought stress, but more accumulation was noticed with the application of CSNPs. Overall, this study is the first on using CSNPs to mitigate drought stress of C. roseus by inducing the antioxidant potential and gene expression of alkaloid biosynthesis.

关键词： Biochemistry   Cadmium   Histopathology   Immunohistochemistry   Ovaries   Purslane   KAPPA-B   PORTULACA-OLERACEA   TRANSCRIPTION FACTORS   REPRODUCTIVE-SYSTEM   UP-REGULATION   TOXICITY   CYTOTOXICITY   MECHANISMS   TISSUES   METALS  

摘要： The aim of this study is to describe the existence of the inflammatory marker nuclear factor kappa light chain B lymphocyte protein (NF-B P65) in the tissue as a response to cadmium (CdCl2) toxicity. Next is to describe the disappearance of the NF-B P65 in response to the purslane plant treatment to explore its anti-inflammatory effect, also describing the histopathological and biochemical changes that occurred from CdCl2 toxicity and the purslane plant tissue protections. There are four experimental groups, 32 rats (n = 8) intraperitoneally injected with CdCl2 and orally administered with purslane plant extract (according to groups) for 30 days: group one (control), group two (purslane extract 2 g/kg bw), group three (CdCl2 3.5 mg/kg bw), group four (CdCl2 3.5 mg/kg bw + purslane plant extract 2 g/kg bw). The biochemical findings showed that ovaries and brain tissue homogenates in group three showed malondialdehyde increase and reduction in catalase, total antioxidant capacity, and acetylcholine esterase. A reduction in serum LH, FSH, and estradiol were also recorded. These parameters became normal in group four. The histopathological findings exhibited that group three showed ovarian and cerebral hemorrhage and lung pneumonia. Tissues of group four were protected and no pathological lesions were detected. The immunohistochemical results showed that the inflammatory marker NF-B P65 in group three was strongly detected in the spleen and moderately detected in the ovaries, brain, and lung but negatively detected in the tissues of group four. In conclusion, CdCl2 induced ovarian toxicity and the NF-B P65 existence was increased. Purslane plant protected rats from CdCl2 toxicity and decrease NF-B P65.

关键词： 食品化学  

ISBN: (纸本)9787518072590

摘要： 本书以食品主要成分为主线，讲述了水分、矿物质、糖类、脂类、蛋白质、核酸、酶、维生素与辅酶等食品成分的结构、性质、功能以及这些物质在食品加工贮藏过程中的变化和在人体内的代谢调节。

关键词： Caviar   Fish roe substituent   Wild &farmed sturgeon   Authenticity   Processing   Biochemical analysis  

摘要： Background: Caviar, salt-cured unfertilized roe of sturgeon fish, is a food delicacy associated with royalty and nutritive properties since prehistoric times. The drastic decline in wild sturgeon populations has led to an increased aquaculture production of caviar roe and its substitutes from other species i.e. lumpfish, herring, tobiko, cod, shad and mullet. Fish roes are highly nutritive foods comprising a myriad of biochemical components with several health benefits viz. high quality protein, polyunsaturated fats, vitamins and minerals which are influenced by its biodiversity, fish farming and industrial processing. Scope and approach: We provided in this review extensive knowledge regarding interspecies compositional variability among roe produced by different fish species, with respect to the impact of fish farming, different processing methods and storage conditions on caviar/roe quality. Different quality control methods viz. biochemical, analytical and molecular methods, for evaluating caviar authenticity and biodiversity of roe products are summarized as essential tools to assess roe counterfeiting and/or mislabeling. Key findings and conclusions: Biochemical markers for discriminating the roe origin (wild vs. domesticated fish) are highlighted with lipid profiles being more efficient than protein analysis. Molecular genetic techniques were also posed as competent species-discriminatory tools. Other underexploited tools were introduced as future perspectives viz. color measurements and computer vision, as rapid non-destructive methods. Intelligent packaging should be sought as a valuable method for monitoring roe freshness. The full health benefits of roe, as a promising functional food, are not yet fully capitalized upon which warrants future research to prove its efficacy using mechanistic and clinical studies.

关键词： Dye removal   FoLacc5   Fusarium oxysporum   Laccase   Pichiapastoris   EXTRACELLULAR LACCASE   TRAMETES-VERSICOLOR   CRYSTAL-STRUCTURE   SYNTHETIC DYES   EXPRESSION   GENES   RESOLUTION  

摘要： A putative laccase was cloned from cDNA of Fusarium oxysporum HUIB02, which resulted in a highly specific amplicon of 1.8 kb. Nucleotide sequence consisting of 1875 nucleotides, encoding for a polypeptide of 623 amino acids and shared 99% similarity to other F. oxysporum putative laccase gene. Hence, the gene was named as FoLacc5. FoLacc5 was expressed in P. pastoris and qualified the expression as extracellular protein. SDS-PAGE and western blot analysis indicated rFoLacc5 has a molecular weight above 100 kDa in glycosylated form. Optimal culture conditions enhanced the enzyme production level to 21,966 U/L. The optimal culture conditions was YPM medium, initial pH of 6.5, shaking speed of 210 rpm, inoculation temperature of 30 degrees C, and Cu2+ concentration of 0.08 mM. rFoLacc5 exhibited maximal activity at pH of 3.5 and temperature of 40 degrees C. Fe3+ and Cu2+ showed different effect on rFoLacc5 which Fe3+ ion completely inhibited, whereas Cu2+ ion increased enzyme activity. rFoLacc5 removed various synthetic dyes including brommothymol blue, methylene blue, methyl orange, remazol brilliant blue R, aniline blue, evans blue, indigo carmine, and orange II. This is the first study conducted on characterization of recombinant laccase rFoLacc5 and its application on synthetic dyes removal. rFoLacc5 shows great potential for biotechnology application on dyes removal.

关键词： L-serine   D-serine   NAD   biochemical properties   metabolism   NMDA receptor   neurotransmission   cancer progression   phosphorylated pathway   serine deficiency  

摘要： The human enzyme D-3-phosphoglycerate dehydrogenase (hPHGDH) catalyzes the reversible dehydrogenation of 3-phosphoglycerate (3PG) into 3-phosphohydroxypyruvate (PHP) using the NAD(+)/NADH redox cofactor, the first step in the phosphorylated pathway producing L-serine. We focused on the full-length enzyme that was produced in fairly large amounts in E. coli cells; the effect of pH, temperature and ligands on hPHGDH activity was studied. The forward reaction was investigated on 3PG and alternative carboxylic acids by employing two coupled assays, both removing the product PHP; 3PG was by far the best substrate in the forward direction. Both PHP and alpha-ketoglutarate were efficiently reduced by hPHGDH and NADH in the reverse direction, indicating substrate competition under physiological conditions. Notably, neither PHP nor L-serine inhibited hPHGDH, nor did glycine and D-serine, the coagonists of NMDA receptors related to L-serine metabolism. The investigation of NADH and phosphate binding highlights the presence in solution of different conformations and/or oligomeric states of the enzyme. Elucidating the biochemical properties of hPHGDH will enable the identification of novel approaches to modulate L-serine levels and thus to reduce cancer progression and treat neurological disorders.

关键词： cardiac marker   cardiology   cardiomyopathy   cardiopathy   hemogram   primates   CARDIOMYOPATHY  

摘要： Background The cardiovascular system of owl monkeys has been studied due to frequent postmortem findings of heart disease in asymptomatic animals. The silent aspect and the difficulty of early diagnosis intensify the importance of studying the cardiovascular system in this species. Methods Echocardiogram evaluation was carried out on 60 animals, grouped into suspect or non-suspect of having heart diseases, and evaluated through electrocardiogram, hematology, and biochemical tests. Results Doppler echocardiography indicated two animals with suspicion of left ventricular hypertrophy and eight with dilated cardiomyopathy. Suspect animals had higher cardiac measurements and reduced shortening fraction. Troponin I was detectable in two animals (0.128 ng/mL and 0.584 ng/mL), and serum albumin concentration was significantly higher in non-suspect animals (P < .05). Conclusions The importance of echocardiographic measurements of IVSd, IVSs, LVIDd, LVIDs, LVPWd, LVPWs, LA, EF, and FS in the cardiac evaluation of captive owl monkeys was evidenced.