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关键词： Sweet corn kernels   Packaging   Storage   Degradation kinetics  

摘要： The degradation kinetics of dehydrated sweet corn for total sugar, ascorbic acid, TSS, pH, rehydration parameters, colour and moisture content using low density polyethylene pouches (LDPE) and laminated aluminium foil pouches (LAFP) with or without vacuum were studied. The samples were kept for 3 months and were analysed at every 15 days. During the storage, total sugar, ascorbic acid and total soluble solids reduced from 10.50 to 9.73 g/100 g, 9.36 to 8.86 mg/100 g, 83 to 51 degrees Brix respectively. Rehydration coefficient and rehydration ratio reduced from 90.28 to 75.27, 2.64 to 1.56. Colour L* value, a* value. b* value changed from 61.00 to 70.13, 42.93 to 53.27, 55.58 to 64.24 respectively resulting in increase in AE value and chroma value up to 16.29, 70.23 to 83.45 respectively. The moisture content increased from 2.12 to 3.92% in packages. The average sensory score of 7.86 even after 90 days of storage in laminated aluminium foil pouch with vacuum indicates that the product may be stored for 90 days satisfactorily. Zero and first order models fitted well and can be used for predicting various properties of dehydrated sweet corn during storage. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： astaxanthin   Channa argus   growth   immune response   inflammatory response   serum biochemistry  

摘要： The present study investigated the effects of dietary astaxanthin on the growth, blood biochemical, antioxidant, immune and inflammatory response in lipopolysaccharide-challenged Channa argus. A total of 0, 50, 100 and 200 mg/kg of astaxanthin were added to the basal die for 56 days. After the feeding experiment, each group was subjected to a lipopolysaccharide challenge (except for the Control group). The results showed that adding astaxanthin to the diet can significantly increase the weight gain and specific growth rate and decrease the feed conversion ratio of C. argus;the highest weight gain, specific growth rate and minimum feed conversion ratio occurred in the 100 mg/kg group. Furthermore, dietary astaxanthin supplementation can alleviate the negative effects of lipopolysaccharides by increasing the levels of alkaline phosphatase, lysozyme, complement 3, complement 4, total serum protein, albumin, globulin, superoxide dismutase, catalase and glutathione peroxidase and decrease the serum cortisol, aspartate aminotransferase, alanine aminotransferase, glutathione peroxidase, and malondialdehyde. Dietary astaxanthin supplementation also can decrease the relative expression of inflammatory genes (nuclear factor kappa B, interleukin-1, interleukin-8 and tumour necrosis factor-alpha) in the liver, spleen, kidney and intestine. To summarise, dietary astaxanthin addition can improve the growth performance and attenuate the negative effects of lipopolysaccharide challenge in C. argus. The optimal amount of astaxanthin is 100 mg/kg.

关键词： adjuvant therapy   chemotherapy   myeloperoxidase   testicular inflammation   testosterone  

摘要： Cyclophosphamide (CP) is commonly used as antineoplastic and immunosuppressant drug with noticeable gonadotoxic profile. Nerolidol (NER) is a sesquiterpene with potent antioxidant and anti-inflammatory properties. Thus, the present study was designed to explore its possible gonadal protective potential against cyclophosphamide-induced testicular, epididymal, seminal and spermatozoal toxicities. Animals were divided into five groups: control (normal saline for 14 days), treatment group (NER 200 and 400 mg/kg, p.o) for 14 days along with a single dose of cyclophosphamide (200 mg/kg, i.p) on 7(th) day, toxic and Per se groups (cyclophosphamide 200 mg/kg i.p) on 7(th) day and NER 400 mg/kg for 14 days respectively. Animals were sacrificed on the 15 day, and body weight, weight of reproductive organs, testosterone level, sperm count, biochemical parameters, histopathological and immunohistochemical studies were performed in the testes, epididymis and in the serum. CP administration induced oxidative stress, nitrative stress, inflammation, reduced testosterone level, sperm count, increased expression of MPO and caused histological aberrations in the testes, epididymis and seminal vesicles. CP caused reduced sperm count, sperm motility and testosterone level which got reversed upon treatment with nerolidol in a dose-dependent manner. Nerolidol thus acted as a gonadoprotective molecule and prevented the gonadotoxicity of CP.

关键词： BRD4 bromodomain   curcumin degradation   ferulic acid   protein kinase CK2   X-ray crystallography  

摘要： Protein kinase CK2 is an antiapoptotic cancer-sustaining protein. Curcumin, reported previously as a CK2 inhibitor, is too bulky to be accommodated in the CK2 active site and rapidly degrades in solution generating various ATP-mimetic inhibitors;with a detailed comparative analysis, by means of both protein crystallography and enzymatic inhibition, ferulic acid was identified as the principal curcumin degradation product responsible for CK2 inhibition. The other curcumin derivatives vanillin, feruloylmethane and coniferyl aldehyde are weaker CK2 inhibitors. The high instability of curcumin in standard buffered solutions flags this compound, which is included in many commercial libraries, as a possible source of misleading interpretations, as was the case for CK2. Ferulic acid does not show any cytotoxicity and any inhibition of cellular CK2, due to its poor cellular permeability. However, curcumin acts as a prodrug in the cellular context, by generating its degradation products inside the treated cells, thus rescuing CK2 inhibition and consequently inducing cell death. Through the intracellular release of its degradation products, curcumin is expected to affect various target families;here, we identify the first bromodomain of BRD4 as a new target for those compounds. DatabaseStructural data are available in the PDB database under the accession numbers (CK2 alpha/curcumin), (CK2 alpha/ferulic acid), (CK2 alpha/feruloylmethane), (CK2 alpha/ferulic aldehyde), (CK2 alpha/vanillin) and (BRD4/ferulic acid).

关键词： Mangrove   Vectors   GC-MS   Pathogens   Detoxifying   Enzymes  

摘要： Mosquitoes are principal vector of several vector-borne diseases affecting human beings leading to thousands of deaths per year and responsible for transmitting diseases like malaria, dengue, chikungunya, yellow fever, Zika virus, Japanese encephalitis, and lymphatic filariasis. In the present study, we evaluated the different solvent extracts of mangrove Avicennia marina for their toxicity against larvae of three major mosquito vectors, as well as selected microbial pathogens. The larvicidal mortality of third instars was observed after 24 h. Highest larval mortality was found for the acetone extract of A. marina against Culex quinquefasciatus (LC50 = 0.197 mg/ml;LC90 = 1.5011 mg/ml), Anopheles stephensi (LC50 = 0.176 mg/ml;LC90 = 3.6290 mg/ml), and Aedes aegypti (LC50 = 0.164 mg/ml;LC90 = 4.3554 mg/ml). GC-MS analysis of acetone extract revealed 5 peaks, i.e., 1-hexyl-2-nitrocyclohexane (3.229%), eicosanoic acid (40.582%), cis-9-hexadecenal (70.54%), oleic acid (4.646%), and di-N-decylsulfone (5.136%). Parallel to larvicidal assay, sub-lethal dosage acetone extracts severely affected the enzyme regulations (alpha,beta-carboxylesterase, GST and CYP450) of third instars. Larval and pupal durations increased in all treatment sub-lethal dosage (0.127, 0.151, 0.177, and 0.197 mg/ml), whereas egg hatchability and means of fecundity decreased compared to control. The survival rate was reduced statistically in Cx. quinquefasciatus (chi(2) = 23.77, df = 1, P = 0.001) in all the treatment dosages as compared to the control. Antimicrobial activity assays showed significant growth inhibition post treatment with acetone and methanol extracts against Salmonella typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus pneumoniae, Escherichia coli, and Shigella flexneri. Overall, these results indicated the potential employment of A. marina extracts as a source of natural mosquitocidal and antimicrobial compounds of green-based environment.

摘要： Corrigendum to 'Biochemical and biophysical characterization of curcumin binding to human mitotic kinesin Eg5: Insights into the inhibitory mechanism of curcumin on Eg5' [Int. J. Biol. Macromol. 9 Curcumin potentiated the mitotic arrest and monopolar spindle formation in HeLa cells in synergism with monastrol. Cells exhibiting monopolar spindles upon treatment with mentioned concentrations of the drugs were counted by visualizing the centrosomes, DNA and microtubules. [Extracted from the article]

关键词： Selenium   Sprouts   Phenolic acids   Speciation analysis   Cytotoxic activity  

摘要： Background: The sprouts of Brassica vegetables are known from their nutritional and chemopreventive values. Moreover, sprouts fortification with some trace elements, like selenium, may increase their importance in human diet. Thus, the aim of our study was to examine if selenium enrichment of kale and kohlrabi sprouts may influence their biochemical properties (phenolic acids and L-tryptophan content, antioxidant potential) or cytotoxic activity. Additional aim of the study was to evaluate the profile of selenium compounds and to describe the multidimensional interactions between the mentioned parameters. Methods: Selenium content in the sprouts was evaluated by double-channel atomic fluorescence spectrometer AFS-230 with the flow hydride-generation system. Separation of selenium species in water soluble fraction was performed by size-exclusion LC-ICP-MS. The identification and quantification of phenolic acids and L-tryptophan was performed by HPLC. For antioxidant activity DPPH and FRAP methods were used. Cytotoxic activity of the sprouts extracts on a panel of human metastatic carcinoma cells was evaluated by MTT test. Results: Selenium content in the fortified sprouts was several orders of magnitude higher than in the unfortified ones. Only small percentage of supplemented selenium (ca. 10 %) was incorporated into the sprouts as seleno-L-methionine, while the other detected selenium species remained unidentified. Selenium fortification differently stimulated the production of phenolic acids (sinapic, chlorogenic, isochlorogenic and caffeic acid) in the tested sprouts, depending on the particular species, selenium dose and the investigated compound. PCA analysis revealed strong correlation between antioxidant parameters and phenolic acids and L-tryptophan, while Se correlated only with caffeic acid. The sprouts extracts (>= 1 mg/mL) showed cytotoxic potency to all the studied cancer cell lines (SW480, SW620, HepG2, SiHa), regardless the selenium supplementation. C

关键词： Environmental microbiology   In situ hybridization   Surface-enhanced Raman spectroscopy   X-ray spectroscopy   Silver   Single-cell imaging  

摘要： The vast majority of environmental bacteria remain uncultured, despite two centuries of effort in cultivating microorganisms. Our knowledge of their physiology and metabolic activity depends to a large extent on methods capable of analyzing single cells. Bacterial identification is a key step required by all currently used single-cell imaging techniques and is typically performed by means of fluorescent labeling. However, fluorescent cells cannot be visualized by ion- and electron microscopy and thus only correlative, indirect, cell identification is possible. Here we present a new method of bacterial identification by in situ hybridization coupled to the deposition of elemental silver nanoparticles (silver-DISH). We show that hybridized cells containing silver can be directly visualized by light microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, secondary ion mass spectrometry (nanoSIMS), and confocal Raman micro-spectroscopy. Silver-DISH did not alter the isotopic (C-13) and elemental composition of stable-isotope probed cells more than other available hybridization methods, making silver-DISH suitable for broad applications in stable-isotope labeling studies. Additionally, we demonstrate that silver-DISH can induce a surface-enhanced Raman scattering (SERS) effect, amplifying the Raman signal of biomolecules inside bacterial cells. This makes silver-DISH the only currently available method that is capable of delivering a SERS-active substrate inside specifically targeted microbial cells. (C) 2020 Published by Elsevier GmbH.

ISBN: (纸本)9787030631527

关键词： Cochliobolus miyabeanus   Oryza sativa   Climate change   Open-top chambers   Plant-pathogen interaction  

摘要： The leaf anatomy, photosynthetic system parameters and accumulation of carbohydrates were determined at different times for Bipolaris oryzae pathogenesis in two rice cultivars (BRS Querencia and Inov CL), grown in an environment with 400 ppm or 700 ppm of atmospheric CO2. The results demonstrated that the plants exposed to 700 ppm underwent changes in anatomical characteristics (reduction in parenchyma thickness and size of bulliform cells), photosynthetic parameters (increased carbon assimilation rate, leaf intercellular CO2 concentration and water use efficiency, and reduction of stomatal conductance to water vapor, transpiration rate and carboxylation efficiency), and carbohydrate accumulation (increased concentration of soluble sugars and starch), when compared to plants at 400 ppm. Therefore, the changes in morphological traits of the leaf and the accumulation of carbohydrates, which were stimulated in the rice plants by increased CO2 concentration (700 ppm), were associated with less severe brown spot, caused by B. oryzae.