课程文献中心 更多>>

关键词： Microalgae   Copepods   Cyclops abyssorum divergens   Biochemical composition   Polyunsaturated fatty acids   Amino acids  

摘要： Recently, the use of microalgal bioproducts in aquaculture research has gotten consideration. The current study aims to screen the biochemical components of three microalgae: Nannochloropsis salina, Chlorella salina and Tetraselmis chuii for using in the feeding of Cyclops abyssorum divergens copepods that are suitable prey for the mouth gape of the cultured fish larvae. The effect of different initial densities of these algal cells used for copepods feeding was determined by estimation of proximate composition, polyunsaturated fatty acids (PUFAs), amino acids (AAs) and enzyme activities of copepods. N. salina showed high protein and lipid contents, while C. salina presented high carbohydrate content. C. salina and T. chuii presented high PUFAs, with proportions of 22.35 and 22.67%, respectively, and are considered as the source of n-3 fatty acids. Also, they had higher concentrations of total AAs (21.46 and 24.14 mg. g(-1) dry wt., respectively). The experiment study showed that the C. salina diet at an initial concentration of 1 x 10(6) cells ml(-1) resulted in a maximum increase of copepods population density (503.3%) and high protease and trypsin activities (42.65 and 31.80 U. mg(-1) protein, respectively) in copepods. T. chuii diet at an initial concentration of 1 x 10(6) cells ml(-1) resulted in a maximum protein, lipid, PUFAs and AAs contents of copepods. Therefore, C. abyssorum divergens copepods after 18 days feeding with an initial concentration of 1 x 10(6)C. salina or T. chuii cells ml(-1) are the suitable candidate diets in larviculture because they achieved higher productivity and attained better nutritional composition of the copepods.

关键词： Pyrethroids   3-Phenoxybenzoic acid   Microbial food cultures   Bioremediation   Pathway   Genetic engineering  

摘要： As a biologically inspired insecticide, pyrethroids (PYRs) exert evident toxic side effects on non-target organisms. PYRs and their general toxic intermediate 3-phenoxybenzoic acid (3-PBA) have shown high detection rates/levels in human beings recently, for which diet was identified as the major exposure route. Microbial mineralization has emerged as a versatile strategy in addressing such escalating concern. Herein, PYRs and 3-PBA biodegradation with regards to strain safety, application and surfactant were summarized. Numerous PYRs-degrading microbes have been reported yet with a minority focused on 3-PBA. Most isolates were from contaminated sites while several microbial food cultures (MFCs) have been investigated. MFCs such as Bacillus spp. and Aspergillus spp. that dominate in PYRs-degrading microbial pools are applicable candidates for agricultural by-products detoxification during the postharvest process. Subsequently, we discussed committed degradation steps, wherein hydrolase responsible for PYRs ester linkage cleavage and oxygenase for 3-PBA diphenyl ether bond rupture play vital roles. Finally, comprehensive information of the key enzyme genes is outlined along with methodologies concerning gene cloning. Cytochrome P450 monooxygenases (CYP) is competent for diphenyl ether scission. Newly-developed omics has become a feasible gene and enzyme mining technology. To achieve PYRs mineralization in feed and food commodities, the screening of MFCs rich in related enzymes and the construction of MFCs-derived genetically modified microbes (GMMs) exhibit great potential considering the safety issues. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Graphene   Nanocomposite   Ag nanoparticle   Stevia rebaudiana Bertoni   Plant extract  

摘要： Stevia is a source of natural sweetener. Numerous researches showed that silver nanoparticles affected the yield and growth of agricultural crops. The effect of silver, graphene, and nanocomposite nanoparticles on a few biochemical and morphological parameters of the Stevia plant were studied. Synthesized Ag nanoparticles were confirmed by the absorption maxima and SEM micrograph. The use of nanocomposites at 40 mM, resulted in the higher chlorophyll content (25%) and increased accumulation of soluble sugars (27%), flavonoids (51%), total phenol (33%) and total protein (51%) as compared to the control plants. The plants treated with nanocomposite at a concentration of 60 mM, had more stevioside and rebaudioside content than plants treated with nanocomposite at a concentration of 40 mM.

关键词： Antioxidant   Catechin   Firmness   Flavonoids   Phenolics   Vitamin C  

摘要： The study was conducted to determine the effects of different rootstocks (Ma x Ma 14, GiselA 5, GiselA 6 and SL 64) on quality properties and bioactive compounds of '0900 Ziraat' sweet cherry fruit. Fruit weight, thickness and length of Ma x Ma 14 and SL 64 was higher than the GiselA 5 and GiselA 6. Firmness of GiselA 6 was lower than the other rootstocks (Ma x Ma 14, GiselA 5 and SL 64). The chroma value of GiselA 5 was greater than the other rootstocks, whereas the hue angle of SL 64 was lower than the other rootstocks. While the lowest SSC and acidity was obtained in GiselA 5, the highest vitamin C was determined in Ma x Ma 14. Total phenolics and total flavonoids, thus antioxidant activity of GiselA 6 and SL 64 rootstocks was higher than Ma x Ma 14 and GiselA 5 rootstocks. Catechin was the major phenolic acid in '0900 Ziraat' sweet cherry fruit. GiselA 6 had higher catechin and 4-hydroxybenzoic acid content than the other rootstocks. As a result, it was revealed that sweet cherry rootstocks were effective on bioactive compounds and fruit quality characteristics.

关键词： Bioaccumulation   Biochemical   Cadmium chloride   Hematological   Toxicity  

摘要： Cadmium is a heavy metal and a non-biodegradable environmental contaminant, and its omnipresence ensures its recurrent exposure to humans and animals. Its intake by chicks leads to fatal implications. Cadmium chloride (CdCl2) because of its bio-accumulative nature is an emerging threat to the poultry industry as well as to the humans which consumes these cadmium-intoxicated chickens. In the current study, the target was to elucidate the toxic effects of CdCl(2)on body weight, hematological, and biochemical parameters as well as its bioaccumulation in different organs of broiler chicks. Various concentrations of CdCl2 (0, 12, 24, 38, and 48 mg/kg body weight) were administered orally to five groups (A, B, C, D, and E) of broiler chicks, respectively. The biometric screening of the exposed birds was carried out by hematological parameters such as packed cell volume (PCV), total erythrocyte count (TEC), mean corpuscular hemoglobin concentration (MCHC), total protein, white blood cells (WBC), and hemoglobin (Hb), as well as biochemical parameters superoxide dismutase (SOD), low-density lipoprotein (LDL), glutathione peroxidase (GPx), and high-density lipoprotein (HDL) with commercially available kits. Metal accumulation in different organs was detected using atomic absorption spectrophotometer. The compound exposure produced a varied impact on broiler birds. Hematological parameters showed a significant decrease except for WBC. Biochemical parameters also decreased significantly in a dose-dependent manner. However, it was revealed that the body weight of chickens was not affected considerably after CdCl2 exposure. A direct relationship was detected between the accumulation of metal within tissues (lungs, heart, and flesh) and exposure frequency. It can be deduced that an increase in Cd deposition in tissues may lead to an alteration in hematological-biochemical markers which may significantly contribute to systemic toxicity in broilers.

关键词： Aflatoxicosis   Phytobiotic   Antifungal   Morphology   Broiler  

摘要： This experiment was conducted to investigate the effects of phytobiotic and antifungal feed additives on the growth performance, blood parameters, intestinal morphology, and cecal microbiota activity of broiler chickens under aflatoxicosis challenge. A total of 250 one-day-old Ross 308 broiler chicks (mixed sex) were reared on the littered floor with a completely randomized design by five treatments and five replicates for 35 days. Treatments included positive control (without AFB1), negative control-AFB1 (1 ppm), negative control-phytobiotic (Entex, 0.5 kg/t), negative control-Mycofix Plus (0.5 kg/t), and negative control-phytobiotic + Mycofix Plus. Dietary phytogenic and toxin binder improved body weight gain and feed conversion ratio of broiler chickens (p<0.05). Serum concentration of AST increased in broilers which received AFB1 without additives, while the blood concentration of total protein decreased (p<0.05). In jejuna morphometric indices, it was observed that the broiler chickens fed phytobiotic additive in combination with toxin binder had a greater villus length and crypt depth (p<0.05). Dietary treatments had no significant effect on the cecal microbial population in broiler chickens. In conclusion, the present results indicated that phytobiotic and toxin binder supplement improved growth performance and intestinal morphology of broiler chickens exposed to AFB1 challenge.

关键词： Porcellanidae   Subtidal   Intertidal   Emersion   Biochemistry   Proteins   Lipids   Glucose   Crustaceans  

摘要： Petrolisthes crabs inhabit a wide range of coastal environments, from the upper intertidal to the subtidal, experiencing regular changes in pH, salinity, and temperature. Hence, such subtidal and intertidal invertebrates are likely to show physiological and biochemical adaptive responses in order to successfully develop during early ontogenetic stages and thus reach reproduction. We herein evaluated the biochemical responses to contrasting environmental conditions of the early ontogenetic stages of two coastal crabs from the Southeast Pacific coast: Petrolisthes laevigatus and Allopetrolisthes punctatus. For this purpose, stage I embryos of both species were subjected to two treatments: (1) emersion (i.e., a daily 3 h aerial exposure until the zoeas hatched) and (2) immersion (i.e., uninterrupted underwater submersion until the zoeas hatched);the total contents of glucose, proteins, lipids, and fatty acids of the organisms were measured in stage I embryos and recently hatched zoeas in order to assess the biochemical constitution of the two species. Both species showed changes in their energetic reserves when treatments within species were compared. Our results found that A. punctatus was negatively affected by stressful periods of emersion, while P. laevigatus showed the opposite tendency and was affected by periods of immersion. The sensitivity of the response and the contrasting outcomes for these two crabs underpin the fact that changes in environmental conditions along the Chilean coast due to climate change (e.g., increased anoxic coastal waters) may have significantly negative consequences on the populations of these ecologically important species and the associated taxa within their ecosystems.

关键词： Pepper   Drying   Chemical composition   Color   Rehydration   Kinetics  

摘要： Effects of different drying methods (open-sun, shade, greenhouse, microwave (300-600 W), air-convective (60- 80 degrees C) and freeze drying) on drying kinetics, biochemical characteristics, rehydration ratio, color and total phenolic content of two different pepper cultivars (Bozok and Pinar) were investigated in this study. Significant differences were observed in biochemical traits of the cultivars and response of cultivars to different drying methods was also different. The greatest crude protein, beta-carotene and lycopene values were recorded for the freeze dryer application. The greatest ascorbic acid values were obtained from freeze dryer and shade drying. Microwave drying process resulted an increment in total phenolic contents of the samples. Except for shade drying, the other methods reduced the oil contents and drying methods significantly influenced fatty acid composition of the samples. The rehydration ratios increased with increasing microwave powers. Chromatic parameters (L*, a*, b*, Delta E) were also influenced by drying temperatures, which contributed to the discoloring of red pepper during the process of drying.

关键词： Growth   Hematology and biochemistry   Hepatic antioxidant   Spotted knifejaw Oplegnathus punctatus   Offshore aquaculture net pen  

摘要： Spotted knifejaw (Oplegnathus punctatus) is a promising species for aquaculture production because of its high commercial value and limited supply. The growth performance, hematological and biochemical parameters, and hepatic antioxidant status of spotted knifejaw reared in an offshore aquaculture net pen system (OANPS) were examined to evaluate the potential development of offshore fish farming on the north coast of China. Results showed that 50, 000 juveniles spotted knifejaw (initial mean body weight 392.73 +/- 58 g) were transferred to OANPS and had a survival rate of 98%, final mean body weight of 790.05 +/- 12.83 g, body weight gain of 101.2%, feed conversion ratio (FCR) of 1.52, and specific growth rate (SGR) of 0.59% d-1 after 120 days. The hepatosomatic and the viscerosomatic indices (HSI and VSI) of the spotted knifejaw did not change significantly. The plasma albumin and globulin contents of the spotted knifejaw reared in the OANPS increased significantly. In contrast, the plasma alkaline aminotransferase and aspartate aminotransferase activities significantly decreased at the end of the experiment. However, the plasma glucose, cholesterol, triglyceride contents and albumin/globulin levels, white blood and red blood cell numbers, hemoglobin, and hematocrit contents showed no significant differences throughout the experimental period. Hepatic superoxide dismutase and glutathione peroxidase activities were significantly increased, and the catalase activity and malondialdehyde levels remained unchanged. In addition, the low hepatic lipid droplet number was observed in the spotted knifejaw reared in the OANPS. These results indicated that juveniles spotted knifejaw reared in an OANPS can show a high survival rate and high growth performance and physiological status through short-term culture. The OANPS opens a new door for spotted knifejaw culture. These findings enhance our understanding of spotted knifejaw aquaculture and contribute to offshore fish farming

关键词： Sparkling base wine   Foam   Acacia gums   Ion exchange chromatography   Macromolecules   SEC-MALLS   Hydrophobic score   Volumetric properties  

摘要： Foam is the first attribute observed when sparkling wine is served. Bentonite is essentially used to flocculate particles in sparkling base wines but can impair their foamability. Gums from Acacia senegal and Acacia seyal improved the foamability of different bentonite-treated base wines. Our main goal was to see how the supplementation with new fractions separated from Acacia gums by Ion Exchange Chromatography affected foamability of sparkling base wines, deepening the relation between foam behavior and characteristics of wine and gums. High molar mass fractions increased the maximal foam height and the foam height during the stability period in, respectively, 11 out and 8 out of 16 cases (69% and 50%, respectively). The properties of the supplementing gums fractions obtained by IEC and, although to a minor extent, the wine characteristics, affected positively and/ or negatively the foam behavior. Wine foamability also depended on the relationship between wine and gums fractions properties.