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关键词： mire ecosystems   oligotrophic bogs   bog water   migration of organic matter   removal of macroelements   PEAT  

摘要： Mire ecosystems in Western Siberia play a significant role in the environment and sustain ecological balance in the biosphere. The aim of the research was to study the chemical and biological processes of mire pedogenesis and the influence of this process on the formation of the composition of bog water and its migration to surface waters. The research was carried out in the southern taiga zone of Western Siberia in a small catchment of the Klyuch River within a catena of geochemically linked mire landscapes. The chemical and microbiological properties of the peat soils were studied in autonomous, transitional, and accumulative geomorphic positions; their influence on the formation of chemical composition of bog water was determined in each position. It was shown that a predominance of certain plant associations (oligotrophic sphagnum, cotton grass, or sedges) caused the accumulation of organic matter of significantly different chemical compositions. The biochemical activity could be traced throughout the peat profiles and affected significantly the chemical composition of bog water. Bog water had certain individual chemical properties in each landscape position. The factors affecting the migration of substances and the removal of chemical compounds beyond the studied profile were determined. The overall removal of macroelements with runoff flows during the growing season amounted up to 4843 kg/km(2) for Ca2+, 51.7 kg/km(2) for total Fe, 1419.0 kg/km(2) for SO42-, 2.253 x 10(-3) kg/km(2) for Pb, 10.037 x 10(-3) kg/km(2) for Cu, 317.29 x 10(-3) kg/km(2) for Mn, 41.191 x 10(-3) kg/km(2) for Zn, 8.151 x 10(-3) kg/km(2) for Ni, and 29.651 x 10(-3) kg/km(2) for Ti. The removal of organic matter reached 583.2 kg C/km(2). The influence of bog water (especially, its organic components) on the water composition in the Klyuch River was clearly shown. Our data on the chemical composition of bog water in the system of geochemically linked more landscapes and on the bog water mi

关键词： Specific spoilage organism   Spoilage behavior evaluation   Little yellow croaker   Spoilage-related volatile indicators   Multivariate statistic analysis   CHEMICAL SPOILAGE   ORGANIC-COMPOUNDS   BACTERIA   STORAGE   VACUUM   SEA   BEEF  

摘要： The objective of this study was to evaluate negative influences of single specific spoilage organism (SSO) on little yellow croaker under modified atmosphere packaging (MAP) by biochemical properties characterization and spoilage-related volatile indicators identification. The assays of chemical spoilage indexes (CSIs) demonstrated that SSO would accelerate deterioration. The Shewanella glacialipiscicola (***)-inoculated fish samples with higher rejection degree (76.47 +/- 2.15%), pH value (7.18 +/- 0.03), TVB-N contents (63.21 +/- 5.13 mg/100 g), K-value (93.76 +/- 4.10%) and lower chewiness value (84.40 +/- 14.39 g), indicated the stronger spoilage ability of S. galacialipiscicola than Carnobacterium maltaromaticum (***). Volatile compound (VOC) metabolites produced by microbial activity were characterized by GC-MS, a total of 21 and 25 VOC compounds were identified in fish sample inoculated with S. galacialipiscicola or C. maltaromaticum, respectively. The spoilage-related volatile indicators were screened through multivariate statistic analysis. The indicators of S. glacialipiscicola were indole and trimethylamine, while indole, trimethylamine and dodecanol were screened for C. maltaromaticum. Furthermore, significant correlation was observed by mathematical models between CSIs and VOC indicators. This study revealed the spoilage behaviors and related VOC production of certain SSO, providing a basis for spoilage mechanism investigation and targeted inhibition of SSO.

关键词： Stickwater   Cooking water   Protein recovery   Antioxidant properties   BY-PRODUCTS   PROTEIN   MEAL   CENTRIFUGATION   TEMPERATURE   GROWTH   JUICE  

摘要： Large volumes of liquid waste are generated in processing operations of seafood industry. Such effluents have high concentrations of soluble protein, but it is necessary to concentrate it for utilization. Therefore, the present study investigated the effects of the use of hydrochloric (HCl) and trichloroacetic (TCA) acids on biochemical and antioxidant properties of recovered solids from sardine stickwater (SSW) and tuna cooking water (TCW). After centrifugation of both raw effluents, solids recovery was performed with the pH-shift method separately using 5 N HCl and 40% TCA as precipitating agents. Specifically, protein recovery was effective (> 80%) only for SSW when both acids were used. An increasing of highmolecular-weight peptides (17 to 158 kDa) in recovered solids resulted from a protein aggregation boosted by the precipitating agents. Concentration of some essential amino acids (Lys, Leu, Ile, Phe and Val) were increased in recovered solids. Except to recovered solids of TCW at pH 11, a low protein solubility (20 to 13%) was observed after treatment with both acids. Elimination of low-molecular-weight peptides and some antioxidant AAs result in a loss of free-radical-scavenging activity, but an increase in ferric reducing antioxidant power was registered for protein concentrates of TCW. [GRAPHICS] .

关键词： 食品微生物  

ISBN: (纸本)9787518081615

摘要： 本书共分为4篇，涉及基础微生物学实验、食品微生物学实验、分子微生物学实验、食品发酵与菌菇栽培实验。内容包括：光学显微镜的使用；细菌的形态与观察等。

关键词： Catalan chub   Mediterranean barbel   Endemic fish   Biomarkers   Perfluoroalkyl substances   Baseline activities  

摘要： Specimens of two endemic cyprinids, Squalius laietanus (Catalan chub) and Barbus meridionalis (Mediterranean barbel), were sampled from a reference site in a small stream of the Ripoll River (NW Mediterranean) outside of their reproductive season. Biomarkers involved in xenobiotic-mediated responses were individually contrasted in fish of both species and 17 perfluoroalkyl substances (PFASs) analysed in muscle to reveal bioaccumulation trends. The parameters were in muscle: cholinesterases, metabolic lactate dehydrogenase (LDH) and citrate synthase (CS); and in liver: cytochrome P450 dependent activities (EROD and BFCOD), carboxylesterase (CE), glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPX) and catalase (CAT). All markers are considered adaptive defence mechanism to face stress. Sensitivity to a model pesticide: dichlorvos was also contrasted in vitro in muscular acetylcholinesterase (AChE) and hepatic CE to reveal species sensitivity to neurotoxic chemicals. Enzymatic activities related to protective mechanisms such as butyrylcholinesterase (BuChE), CE and CAT were higher in chub whereas the antioxidant defences GR and GPX were higher in barbel. Aerobic CS was also higher in barbel while anaerobic LDH was so in chub. EROD activity did not differ between the two species but BFCOD activity was higher in barbel. Levels of PFAS were higher in barbel likely due to its benthic habitat. The in vitro tests revealed higher sensitivity to dichlorvos of muscular AChE in chub (lower IC50) which was probably compensated by a higher catalytic efficiency of CE. All these former biochemical particularities are discussed in terms of fish ecological performance in front of anthropogenic stressors.

关键词： Rosmarinus officinalis   Chromium (VI)   Antioxidant defense system   Histopathology   immunohistochemistry   Hepatotoxicity   OXIDATIVE STRESS   ROSEMARY EXTRACT   ANTIOXIDANT DEFENSE   DAMAGE   ACID   HEPATOTOXICITY   STANDARDS   CURCUMIN   TISSUE   THYME  

摘要： Hexavalent chromium (Cr VI) is widely known as a potential hepatotoxic in humans and animals and its toxicity is associated with oxidative stress. So, an in vivo study was outlined to assess the protective and therapeutic role of Rosmarinus officinalis essential oil (rosemary; REO) against Cr VI-induced hepatotoxicity. Male Wistar rats were assigned into five equal groups (1(st) group served as control; 2(nd) and 3(rd) groups received 0.5 ml/kg BW REO and 2 mg/kg BW Cr VI, respectively; 4(th) group pretreated with REO then injected with K2Cr2O7; and 5(th) group received Cr VI then treated with REO for 3 weeks). Results revealed that rats exposed to Cr VI showed a valuable changes in hematological parameters and an increase in oxidative stress markers (Protein carbonyl, TBARS, and H2O2) and a noteworthy decline in glutathione (GSH) content. Furthermore, a considerable decrease in enzymatic antioxidants (SOD, CAT, GPx, and GST), transaminases (AST and ALT), and alkaline phosphatase (ALP) activities, as well as total protein and albumin levels, was detected, while serum liver function biomarkers were increased significantly. In addition, the evaluation of histopathological and immunohistochemical PCNA expression showed significant variations in the liver that confirm the biochemical results. Administration of REO pre- or post-chromium treatment restored the parameters cited above near to the normal values. Otherwise, individual intake with REO slumped lipid peroxidation and gotten better antioxidant status significantly. Conclusively, REO proved to be an effective antioxidant in modulating Cr VI-induced hepatotoxicity, especially in the pretreated rats.

关键词： Air pollution   Biochemical   Gradation   Green belt   India   Plasticity   Vegetation   ANTICIPATED PERFORMANCE INDEX   TOLERANCE INDEX   SULFUR-DIOXIDE   CHLOROPHYLL CONTENT   HYDROGEN-PEROXIDE   HEAVY-METALS   PLANTS   SO2   LEAVES   CITY  

摘要： The present work was undertaken in order to detect some pollution responsive variables such as ascorbic acid, pH, total chlorophyll, relative water content, total soluble sugar, amino acid and protein of four selected plant species, namely Ficus religiosa, Anthocephalus cadamba, Lagerstroemia speciosa and Cassia siamea, at nine different sites of Durgapur, West Bengal, India. The spatial variability analyses of Air Pollution Tolerance Index (APTI) along with Anticipated Performance Index (API) were also examined on each plant species. In this study, the highest APTI was recorded in L. speciosa (183.54 mg/g) during 2015 at site S5 (CCR), whereas the lowest APTI was reported in C. siamea (11.25 mg/g) during 2014 at site S3 (DGC). The API gradation revealed that L. speciosa was categorised as a best performer followed by A. cadamba and F. religiosa; in contrast, C. siamea showed poor performance among all the sites. One-way ANOVA (at p < 0.05, with Dunnett's post hoc) was conducted for spatial variability analysis both on biochemical parameters and air pollutants (SO2, NOx and SPM) with respect to control site, while two-way ANOVA also operated for the detection of spatio-temporal interaction on concerned biochemical parameters of each tree species. A significant positive correlation was observed both in ascorbic acid and APTI of A. cadamba and L. speciosa with the air pollutants. So it would be said that, for varied environmental situations, different biochemical responses have been reflected by vegetation of the same species. Thus, the present study has tremendous potentiality to screening out tree species on the basis of APTI with pooling their API assessment category and spatial variability detection of biochemical parameters. Biochemical plasticity and adaptability were better revealed on L. speciosa, F. religiosa and A. cadamba which will be suitable for green belt development in air pollution-affected areas.

关键词： Oncorhynchus mykiss   Salinity   Tissue histology   Blood biochemistry   GH   IGF system  

摘要： The objectives of this study were to evaluate the effects of different salinity levels on tissue histology, blood biochemistry, and genes transcription of the GH/IGF system in juvenile golden trout (Oncorhynchus mykiss). Five experimental salinity levels (0, 8, 16, 24, and 32 parts per thousand) were selected to domesticate juvenile O. mykiss for 7 days. Histological characteristics changed with salinity, including higher ionocites area and epithelium thickness in gills, narrow lumen of collecting tubules in kidneys, and high numbers of goblet cells in the intestines. Similarly, increments in slits, degenerate hepatocytes, and individualization of hepatocytes have been shown in fish reared in the 32 parts per thousand salinity group. The lowest triglyceride (TG) and the highest level of total protein (TP) were detected in fish reared at the 32 parts per thousand group. The genes transcription of the GH/IGF system altered in response to the increase of salinity. The present results add to the understanding of the physiological responses of O. mykiss on salinity stress and would be helpful in formulating strategies to optimize the aquaculture of this species in environments with fluctuating patterns of salinity.

关键词： Tilapia fish   Pendimethalin   TEM   Mitochondrial cytochromes   Malondialdehyde profile   OXIDATIVE STRESS   WATER   TOXICITY   BIOMARKERS   EXPOSURE   LIVER   DYSFUNCTION   INDUCTION  

摘要： The mitochondrial defects were evaluated after administering tilapia fish, Oreochromis niloticus to sublethal doses (1.02 and 5.10 mg kg(-1)) of the herbicide pendimethalin (PD). All treatments exhibited a decrease in the cytochrome contents of gills, liver, and brain samples after 12, 24, and 48 h compared with the untreated individuals. However, malondialdehyde (MDA) levels were significantly increased in gills and liver samples. Also, the histopathological profiles showed significant swelling in mitochondria and intracellular spaces in cytoplasm of gills samples. The mitochondrial defects in the treated fish showed a slight decline in cytoplasm/mitochondria ratio (0.92-fold) compared to the control. In hepato-sections of treated fish, destructed mitochondria with less dense matrix as well as some vacuolated mitochondria with matrix disoriented cristae were noted. Similar patterns were observed in brain sections, where destructed axons and a significant decline in cytoplasm/mitochondria ratio (0.52-fold) were found. Therefore, the use of mitochondrial defects and histopathological alterations might represent good markers to assess the impact of herbicides on aquatic organisms. Moreover, the disorganization of cell components is considered an important sign of organ dysfunction.