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关键词： Porphyra haitanensis   Porphyran   Intestinal epithelial healing   Cell proliferation   Cell migration  

摘要： This study examined the beneficial effects of porphyran from Porphyra haitanensis (PHP) on intestinal epithelial cells, in terms of cell proliferation and migration and elucidated the potential molecular mechanism of action of PHP. Purified PHP is a homogenous polysaccharide with a molecular weight of 2.01 x 10(5) Da, intrinsic viscosity [eta] of 463.76 mL/g, and radius of gyration of 61.2 nm. When the intestinal epithelial wound healing activity of PHP was investigated in vitro using the IEC-6 cell line (intestinal epithelial cells-6), it was found that PHP could promote cell migration and proliferation. PHP enhanced the protein expression of cell division control protein 42, paxillin, and focal adhesion kinase, which suggest that PHP might modulate the expression of these proteins to improve intestinal epithelial healing. Thus, this study indicated that PHP could serve as a potential source of functional food constituents for intestinal epithelial protection and restoration.

关键词： Chitosan   Hemicelluloses   Packaging film   TiO2   Functional properties  

摘要： The aim of this study was to investigate the physicochemical properties of chitosan (CS) based composite films with the incorporation of hemicelluloses (HC). Films were obtained via direct immersion method and characterized in terms of structural and morphological properties by FT-IR, XRD, XPS, SEM and EDS. By combining with the increased HC loading efficiency (L) and swelling property (S) of films with the increased HC content to 5%, this study proved the increased hydrogen bond interactions between CS and HC. Films with the tensile strength of 32.81 +/- 4.97 MPa and elongation at break of 39.63 +/- 4.67% were obtained with 3% HC and 20% glycerol (GC). The water vapor permeability (WVP) of films developed with the increased HC and GC contents, while the oxygen permeability (OP) decreased. Moreover, antibacterial testing indicated that all films exhibited the increased growth inhibition against E. coli and S. aureus as increasing TiO2 content.

关键词： OMW   physicochemical characterization   microbiological counts   PCA   northern Morocco  

摘要： This work examined the influence of crop season, extraction system and production site on the composition of fresh olive mill wastewater collected from northern Morocco. ANOVA analysis showed that most of the traits were largely affected by the extraction system (>= 60% of total variance). Comparison among extraction systems showed significant differences for all traits, except for chlorides. Three phase centrifugation system (C3) displayed the highest value of total phenols, while all the remaining traits were higher in two phase centrifugation system (C2). Concerning crop seasons, we noticed a general decrease in values of total solids, chemical oxygen demand, chlorides, C/N ratio and total aerobic mesophilic flora, from 2014 to 2016 season;in contrast, an increase in suspended solids, total kjeldahl nitrogen and proteins was detected. OMW with highest total phenols content and then more acidic were collected during 2015 season. Between production sites, Bni Frassen produced OMW with the highest values for salt and total phenols, but the lowest ones were obtained for microbiological traits. OMW from Taza were rich in total kjeldahl nitrogen and proteins. An increase in organic load indicators was observed in Bouchfaa. Principal component analysis (PCA) explained about 82% of total variability: 58%, 16% and 8% for principal component 1 (PC1), PC2 and PC3, respectively. Extraction system fitted the variability of PC1. PC2 was mainly explained by production sites, while PC3 separated crop seasons. Correlation studies showed significant relationships especially among the traits expressing organic load, while microbiological counts were largely associated to total phenols and pH.

关键词： Elementary/Middle School Science   Hands-On Learning/Manipulatives   Water/Water Chemistry  

摘要： Contextualized and socially relevant hands-on activities are an effective way to promote students' involvement in the construction of knowledge. Considering the UN's 2030 Agenda for Sustainable Development, the preservation of water resources is crucial for the sustainable development of a country. Therefore, the PVC project was implemented in the context of water quality monitoring. There were 440 students and 9 chemistry teachers involved. A low-cost portable pedagogical kit was developed in order to determine the temperature, turbidity, pH, concentration of nitrates and nitrites, percentage of dissolved oxygen, salinity, and presence of microplastics in coastal water samples. The results indicate that the hands-on activities have contributed to the learning of chemical contents related to water quality parameters. Finally, the commitment, motivation, and autonomy of the participating students should be highlighted.

关键词： Freshwater ecosystems   Classification   Landscape   South America  

摘要： The baseline conditions for a particular river or stream type are essential to classify aquatic ecosystems based on physical and biological characteristics. In this study, we proposed a river typology for different ecoregions, climate and topography of northwestern Argentina using parameters, and combined key variables to establish reference conditions. A set of geographical, hydro-morphological, hydrological, geological (pedology and sedimentology) and physicochemical variables were measured from different rivers and analyzed with clustering and ordination techniques to develop a typology. We analyzed the correspondence of the physical river conditions and benthic macroinvertebrate assemblages using non-metric multidimensional scaling analysis, dissimilarity among assemblages, ANOSIM approach and envfit analysis in order to make an ecological validation of the classification. Our results allowed us to classify the neotropical rivers studied, according to typological systems adapted from the European Water Framework Directive. The combination of ecoregions and topography along with other variables associated (system B), was better corresponded with biological arrangements. Hence, ecoregions and topography combined turned out to be more precise as a criterion to define river types and their local abiotic and biotic reference conditions. Macroinvertebrate distribution corresponded with the classifications proposed and was related with abiotic features of the rivers. The physical variables as altitude, grain size, water temperature and turbidity were key parameters to develop a schematic model to define river types that could be implemented and tested in other countries of the region. Five river types have been identified, characterized, and included in three large groups: Mountains, Foothills, and Lowlands (Plains). Our results showed that topography and climate are two aspects that strongly influence South American freshwater biota. We propose the schematic model dev

关键词： Os(III) complexes   Pyrazine derivatives   DNA binding ability   Add-base equilibria   Microbiological activity   Homeolysis  

摘要： New series of osmium(III) complexes with pyrazinamide (PZA) and its analogues (PTA, PAOX) were synthesized. The physicochemical features in the solid phase have been identified and confirmed using elemental analysis, mass spectrometry, spectroscopic techniques (FT-IR, H-1 NMR) and thermogravimetric analysis. Based on the studies we confirmed bidentate nature of selected pyrazine derivatives and proven involvement azomethine and amine nitrogen atoms in coordination of metal ion. In particular, complex (2) is more stable than (1) and (3), retaining thermal stability up to 120 degrees C. After one stage dehydration process, the simultaneous destruction of Os(III) complexes architecture was observed with immediate decomposition and elimination of pyrazine derivatives. The acid-base equilibria studies of newly synthesized Os(III) complexes were carried out by combined pH-metric-spectrophotometric and potentiometric titrations in the aqueous solution. Os(III) complexes exhibited rich redox chemistry as demonstrated by cyclic voltammetry. The cyclic voltammograms revealed a well-defined redox couples which correspond to reversible, single-electron Os-III -> Os-II reduction within -1.152 to -1.374 V vs Ag/AgCl and Os-III -> Os-IV oxidation within 0.460-0.831 V vs Ag/*** binding ability of bioactive ligand and their Os( III) complexes with Calf Thymus DNA (CT-DNA) were investigated by spectrophotometric titration. The observed hypsochromic and bat hodromic shifts with simultaneous hyperchromic effect confirmed mixed mode of interaction with biological target Biological activity of Os(III) complexes, i.e. antimicrobial, cytotoxic, haemolytic and photodynamic potential were studied. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Antibiotic drug   Micellar system   Thermodynamic   Spontaneity   Pharmaceutical industry  

摘要： The micellar behaviour of two bio-surfactants, namely sodium cholate (NaC) and sodium deoxycholate (NaDC) in the presence of antibiotic drug viz. ceftriaxone sodium (Cft-Na) has been characterized physicochemically. The aim has been achieved via utilizing conventional conductivity and spectroscopic techniques i.e. UV-Vis and fluorescence probe studies. The knowledge on the alteration in the aggregation mechanism of the studied bile salts induced by Cft-Na has been accessed by means of determining one of the most promising parameters of micellar system called critical micelle concentration (CMC) from conductivity studies. The applicability and acceptability of this conventional technique has been confirmed by determining CMCwith the help of modem spectroscopic techniques i.e. UV-Vis and fluorescence studies. The effect of temperature and drug concentration has also been analyzed by carrying out the studies at different temperatures and concentrations. The variation in the CMC and thermodynamic parameters calculated for the ternary (water + drug + NaC/NaDC) system has been eluridated in terms of assorted interactions that are present in the system by making use of charged pseudophase separation model. The spontaneity in micellization has been found in the presence of drug for the present system. The results of this study are relevant to pharmaceutical industries. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Mitochondria  

摘要： Mitochondrial gene therapy can be seen as a promising tool and a revolutionary approach towards mitochondrial diseases arising from mitochondrial DNA mutations. To pursue this goal, the mitochondria-targeted polycation polyethylenimine (PEI)/triphenylphosphonium (TPP) conjugate has been used to complex and condense both GFP or ND I encoded plasmid DNA (pDNA) aiming at the formation of suitable vectors for mitochondrial gene therapy. The properties of pDNA based TPP-polyplexes have been addressed and appear to be valuable for gene delivery applications. In vitro studies using fluorescent pDNA demonstrated the internalization of the developed carriers and mitochondria targeting. Evidences of gene expression into mitochondria are also reported. Following this achievement, significant levels of both mitochondrial recoded GFP and ND1 proteins were quantified. This work represents a great step towards effective mitochondria-targeting gene delivery and functional protein expression, providing a significant contribution in mitochondrial gene therapy field. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Free energy   Anions   Liquids   Mixtures   Phase equilibria  

摘要： The physicochemical properties of the (LiF (1) + MgF2 (2))(eut) + LaF3 (3) molten system have been investigated. The phase equilibria, density and volume properties, electrical conductivity, and surface tension have been selected for investigation. The phase equilibria have been measured by thermal analysis method, and the CALPHAD method for optimizing of the phase diagram has been used in order to interpret the obtained experimental data. Calculated values of the eutectic point of the binary system (LiF (1) + MgF2 (2))(eut) have the following coordinates: eutectic temperature T-eut = 998 K and x(2) = 0.3095 and calculated composition of the ternary eutectic, according to the thermodynamic model, are at x(1) = 0.6627, x(2) = 0.2718, and x(3) = 0.0655. The Archimedean method of hydrostatic weighing was used for density measurements, a method based on the principle of phase shift measurement was used for electrical conductivity measurements, and the maximum bubble pressure method was used for surface tension measurements. The calculated concentration dependencies of particular physicochemical properties showed increasing character for density, partial molar volume, and electrical conductivity, while decreasing character was observed for surface tension. These data have been compared with corresponding physicochemical properties of two other molten systems: (LiF + CaF2)(eut) + LaF3 and (LiF + NaF)(eut) + LaF3.

关键词： Carvacrol   Rhamnolipid   Antimicrobial activity   Zein   Docking  

摘要： Carvacrol is a phenolic monoterpenoid obtained from the genera of Origanum, Thymus, Satureja, and Lippia. It is a hydrophobic phytoconstituent that readily tends to decay while processing leading to restricting its potential application. In the current study, zein/rhamnolipid (ZRL of 306 nm) complex nanoparticles were loaded with carvacrol successfully (CRZRL of 271 nm) to explore its antimicrobial activity and obtained the MIC value of 135 mu g/ml and 270 mu g/ml against P. syringae (bacterial canker) and F. oxysporum (Fusarium wilt) respectively. These complex nanoparticles were further characterized by DLS, FE-SEM, DSC, FT-IR, (HNMR)-N-1, docking, and HPLC studies. The strong interaction of carvacrol with zein and rhamnolipid complex nanoparticles which showed characteristic peaks in FTIR as well as (HNMR)-N-1 were also supported by our docking studies. This strong interaction resulted in higher EE (95%) as well as LE (42%), confirmed by HPLC studies. Docking studies further revealed the presence of stronger Pi-Pi interaction within binding and active sites of zein through which rhamnolipid and carvacrol interact. The developed nano-formulation could be exploited for controlling different plant diseases and other foodborne pathogens.