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71.
de Oliveira Amanda Gerhardt Moreno Janaina Fernandes de Sousa Ana Maria Furtado Esccio Viviane Alves de Oliveira Cavalcanti Guimares Maria Jos da Silva Ana Lucia Nazareth 《Polymer Bulletin》2020,77(6):2889-2904
Polymer Bulletin - Investigating the compatibility mechanism of hybrid composites based on two polymers and one mineral nanofiller is a challenge that needs to be better understood. This study... 相似文献
72.
The effect of disintegration severity on starch hydrolysis and ethanol production from cassava roots and stems has been evaluated. It was found that a considerable fraction of the starch in the roots was made available for hydrolysis with relatively crude processing; all such material was readily fermented. To achieve a very high fermentables yield, either very intensive processing or, preferably, a two stage process, with the second stage being applied only to the oversize material, is required. Whether it is economically viable to process the oversize material further depends on a number of site-specific factors. The two stage option appears the more attractive alternative especially in small to medium size cassava to ethanol plants because of the need to minimise power requirements and thereby steam usage. 相似文献
73.
Influence of olive ripening degree and crusher typology on chemical and sensory characteristics of Correggiolo virgin olive oil
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74.
Baffone W Casaroli A Citterio B Pierfelici L Campana R Vittoria E Guaglianone E Donelli G 《International journal of food microbiology》2006,107(1):83-91
Water is known as one of the main transmission routes of Campylobacter and contributes to increase the number of sporadic infections and outbreaks. Campylobacter jejuni persists in the environment, especially in water, in a viable but non-culturable (VBNC) form that is thought to be a possible cause of water-borne outbreaks. In this study, we evaluated the loss of culturability and viability of 9 C. jejuni strains of clinical origin and one ATCC reference strain when kept at 4 degrees C in artificial sea water (ASW). Culturability was measured as colony-forming units while viability was evaluated by CTC-DAPI double staining and the combined CTC-specific fluorescent antibody technique (CTC-FA). When cultured on Columbia Agar plates, strains exhibited different growth profiles which allowed to classify them into three different groups. Both techniques used to monitor the viability of the bacterial cells showed that C. jejuni strains survived in the VBNC form in the microcosms through a period lasting from 138 to 152 days. The recovery of C. jejuni VBNC forms to culturability, as evidenced by cell division, was obtained by passage in the mouse intestine. Our results indicate that C. jejuni VBNC cells were able to remain in this state for a few months and regain their culturability after in vivo passage depending on their lasting in the VBNC state, which affects the number of respiring bacteria. In fact, the resuscitation was achieved when the number of respiring bacteria became higher than 10(4) cell/ml. Therefore, a relatively high microbial titer of respiring bacteria in the VBNC state seems to be important for the resuscitation and subsequent intestinal colonisation. 相似文献
75.
Ferracin LM Fier CB Vieira ML Monteiro-Vitorello CB Varani Ade M Rossi MM Müller-Santos M Taniwaki MH Thie Iamanaka B Fungaro MH 《International journal of food microbiology》2012,155(3):137-145
In silico comparison of 34 putative pks genes in Aspergillus niger strain CBS 513.88 versus A. niger strain ATCC 1015 genome revealed significant nucleotide identity (>95% covering a minimum of 99% of the gene sequence) for 31 of these genes (approximately 91%). A. niger CBS 513.88 harbors three putative pks genes (An01g01130, An11g05940, and An15g07920), for which nucleotide identity was not found in A. niger ATCC 1015. To compare the results of the in silico analysis with the in vivo situation, experimental data were obtained for a large number of A. niger strains obtained from different substrates and geographical regions. Three putative pks genes that were found to be variable between the two A. niger strains using bioinformatics tools were in fact strain-specific genes based on experimental data. The PCR amplification signals for the An01g01130, An11g05940, and An15g07920 pks genes were detected in only 97%, 71%, and 26% of the strains, respectively. Southern blot analyses confirmed the PCR data. Because one of the strain-specific pks genes (An15g07920) is located in a putative ochratoxin cluster, we focused our investigation on that region. We assessed the ochratoxin production capability of the 119 A. niger strains and found a positive association between the presence of this pks gene and the capability of the respective strain to produce ochratoxin. 相似文献
76.
Innocenzo Muzzalupo Massimiliano Pellegrino Enzo Perri 《European Food Research and Technology》2007,224(4):469-475
Characterization of genetic identity using DNA extracted from olive oil has the potential to facilitate assessment of origin
and varietal conformity. Such a prospect is particularly interesting in light of the increased regional spread of olive cultivars
and their various contributions to olive oil mixtures for certification of denomination of origin. Towards this goal, we have
devised a reliable method for extracting DNA from virgin olive oil that was utilized on monovariety oils from the single,
self-sterile cultivar ‘Ogliarola salentina’. We show that DNA purified from oil can be used for microsatellite analysis and
that the profile of DNA purified from a monovariety oil corresponds to the profile of DNA purified from the leaves of the
same cultivar. While DNA from the pollinators present in the genome of the seed embryo, could potentially contain alleles
not present in the genome fruit pulp, invalidating the molecular traceability of olive oil, we show for the first time that
there is no contamination of seed embryo DNA in a monovariety oil. Thus, this molecular assay is applicable for monovariety
olive oils. 相似文献
77.
Maria Elisa Melo Branco de Araújo Yollanda E. Moreira Franco Thiago Grando Alberto Mariana Alves Sobreiro Marco Aurélio Conrado Denise Gonçalves Priolli Alexandra C.H. Frankland Sawaya Ana Lucia T.G. Ruiz João Ernesto de Carvalho Patrícia de Oliveira Carvalho 《Food chemistry》2013
Bioavailability and biological properties of flavonoid glycosides can be improved after the enzymatic hydrolysis of specific glycosyl groups. In this study, we evaluate the antioxidant and antiproliferative potential of rutin after enzymatic hydrolysis performed by α-l-rhamnosidases (hesperidinase from Penicillium sp. and naringinase from Penicillium decumbens) previously heated at 70 °C for 30 min to inactivate the undesirable β-d-glucosidase activity. The highest in vitro antioxidant activity determined by DPPH radical scavenging was achieved with rutin hydrolyzed by hesperidinase. Rutin was predominantly bioconverted into quercetin-3-glucoside. There was no statistical difference between xanthine oxidase inhibition by rutin before and after hydrolysis. However, in vitro inhibitory activity against ten human tumor cell lines showed that hydrolyzed rutin exerted a more potent antiproliferative effect than quercetin and rutin on various cancer cell lines, specially glioma, and ovarian and breast adenocarcinomas. These results indicate that quercetin-3-glucoside could be a promising functional derivative obtained by rutin hydrolysis. 相似文献
78.
Dr. Patricia García‐Domínguez Mélanie Weiss Ilaria Lepore Prof. Dr. Rosana Álvarez Prof. Dr. Lucia Altucci Prof. Dr. Hinrich Gronemeyer Prof. Dr. Ángel R. de Lera 《ChemMedChem》2012,7(12):2101-2112
A novel epigenetic modulator that displays a DNMT1 inhibition and DNMT3A activation profile was characterized (compound 8 ). This compound is a derivative of palmitic acid that incorporates the putative reactive functional group (diynone) of the peyssonenyne natural products. Other analogues containing the diynone or an acetoxyenediyne did not show the same biological profile. In U937 human leukemia cells, diynone 8 induced cell differentiation and apoptosis, which correlated with the expression of Fas protein. Very surprisingly, diynone 8 was toxic to normal human fibroblasts (BJ) and mouse embryo fibroblasts (MEF), but not to immortalized human fibroblasts (BJEL); this unique effect was not observed with the classical DNMT inhibitor 5‐azacytidine. Therefore, compound 8 interferes in a very specific manner with signaling pathways, the activities of which differ between normal and immortalized cell types. This toxicity is reminiscent of the effects of Dnmt1 ablation on mouse fibroblasts. In fact, some of the genes deregulated by the loss of Dnmt1 are similarly deregulated by 8 , but not by the DNMT inhibitor SGI‐1027. 相似文献
79.
The multi-scale Gibbs–Helmholtz constrained (GHC) equation is a new predictive cubic equation of state that constrains the energy parameter in the SRK equation to satisfy the Gibbs–Helmholtz equation. It makes use of internal energies of departure calculated from NTP Monte Carlo simulations at the molecular length scale and a novel up-scaling expression to determine the energy parameter at the bulk phase length scale. 相似文献
80.
Erika J. Obando Montoya Céline Mélin Nathalie Blanc Arnaud Lanoue Emilien Foureau Leslie Boudesocque Gildas Prie Andrew J. Simkin Joël Crèche Lucia Atehortùa Nathalie Giglioli‐Guivarc'h Marc Clastre Vincent Courdavault Nicolas Papon 《Yeast (Chichester, England)》2014,31(7):243-251
Candida guilliermondii (teleomorph Meyerozyma guilliermondii) is an ascomycetous species belonging to the fungal CTG clade. This yeast remains actively studied as a result of its moderate clinical importance and most of all for its potential uses in biotechnology. The aim of the present study was to establish a convenient transformation system for C. guilliermondii by developing both a methionine auxotroph recipient strain and a functional MET gene as selection marker. We first disrupted the MET2 and MET15 genes encoding homoserine‐O‐acetyltransferase and O‐acetylserine O‐acetylhomoserine sulphydrylase, respectively. The met2 mutant was shown to be a methionine auxotroph in contrast to met15 which was not. Interestingly, met2 and met15 mutants formed brown colonies when cultured on lead‐containing medium, contrary to the wild‐type strain, which develop as white colonies on this medium. The MET2 wild‐type allele was successfully used to transfer a yellow fluorescent protein (YFP) gene‐expressing vector into the met2 recipient strain. In addition, we showed that the loss of the MET2‐containing YFP‐expressing plasmid can be easily observed on lead‐containing medium. The MET2 wild‐type allele, flanked by two short repeated sequences, was then used to disrupt the LYS2 gene (encoding the α‐aminoadipate reductase) in the C. guilliermondii met2 recipient strain. The resulting lys2 mutants displayed, as expected, auxotrophy for lysine. Unfortunately, all our attempts to pop‐out the MET2 marker (following the recombination of the bordering repeat sequences) from a target lys2 locus were unsuccessful using white/brown colony colour screening. Nevertheless, this MET2 transformation/disruption system represents a new versatile genetic tool for C. guilliermondii. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献