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关键词： Tomato colour   Cell wall   Fruit ripening   Softening   Shelf life  

摘要： Tomato is the second most important non-cereal crop after potato in terms of consumption and agro-based industries worldwide. In this study, we examined fruit quality characteristics and cell wall-associated fruit softening of three different-coloured tomatoes, 'Sarikiz' with yellow, 'Moda' with orange and 'Cherry' with red colour, harvested at the mature green, breaker, and ripe stages, and stored for the following 3 weeks. Fruit firmness significantly declined in all varieties and reached the softest level in all fruits harvested at the ripe stage and stored for 21 days. The decrease in fruit firmness was related to higher water-soluble pectin, higher expression level of cell wall-related genes, but not related to the integrity of fruit flesh in post-harvest storage conditions. The expression level of SlPSY1 was the highest in Cherry and the lowest in Sarikiz varieties. These results indicate that fruit softening in post-harvest storage conditions is directly related to harvested ripening stage, regardless of the variety.

关键词： Macroinvertebrates   Physicochemical parameter   Water quality   Ghana  

摘要： The health of the lower basin of the Volta River in Ghana was evaluated in January-February and May-June 2016 using physicochemical parameters and benthic macroinvertebrates sampled at 10 locations. Selected environmental variables were compared to accepted environmental water quality standard values where applicable. Principal component analysis (PCA) and redundancy analysis (RDA) were used to analyse the association between the benthic macroinvertebrates distribution and physicochemical variables. Pesticide concentrations were generally below the limit of detection 0.01 and 0.005 mu g/L for organophosphate/synthetic pyrethroid and organochlorines respectively. Nutrient levels were also generally low;however, significant differences existed between the values of physicochemical parameters at the different sampling sites and seasons (Monte Carlo permutation test;p = 0.002), as well as between the abundance of macroinvertebrates at the different sites and seasons (p = 0.002). The environmental variables dissolved oxygen (DO), phosphate, pH, substratum (p < 0.05), turbidity, conductivity, total dissolved solids, total solids and nitrate (0.05 < p < 0.10) significantly explained the variation in macroinvertebrate composition between sampling stations in the Volta River. Polypedilum fuscipenne, was positively correlated with turbidity and DO concentrations;Physa sp., Centroptilum sp., Centroptiloides sp., Phaon iridipennis and juvenile fish were positively correlated with nitrate concentration and pH and negatively correlated with turbidity and DO. Polluted sites were dominated by the snail Lymnaea glabra. This demonstrates that physicochemical parameters and macroinvertebrates could be applied to describe the water quality and improve the biomonitoring for water resources management and the environmental protection in the Lower Volta River.

关键词： Wild blackberry   Yeast fermentation   Physicochemical parameters   Polyphenols   Anthocyanins   Antioxidant capacity  

摘要： Mexico is an extensively diverse country with a wide variety of wild species of blackberries (Rubus spp.), which are rich in bioactive compounds, however, these fruits are underutilized. Fermentation is a process that transforms the chemical compounds of fruits and increases nutraceutical properties. This study aimed to determine the physicochemical changes and the bioactive compounds profile that take place during the fermentation of wild blackberries using yeast EC 1118 and to evaluate its relationship with antioxidant activity (AOx). The results indicated that after 96 h of fermentation the content of carbohydrates (56%), total phenolic compounds (37%), and anthocyanins (22%), decreased, respectively. The physicochemical parameters showed statistic differences (p <= 0.05) at the endpoint of fermentation. The diversity of fatty acids was increased (55%), compared with unfermented blackberries. The modification of carbohydrates, anthocyanins, catechin, gallic and ellagic acid profiles were also monitored performing chromatographic techniques. The AOx, determined by ORAC and DPPH assays, showed the highest results for ORAC at 96 h increased a 140.2%, while DPPH values enhanced a 36.6% at 48 h of bioprocessing. Strong positive correlations were found between fermentation time and DPPH values (r = 0.8131), between ORAC and gallic acid content (r = 0.8688), and between anthocyanin content and pH (r = 0.9126). The fermentation of wild blackberries with EC 1118 yeast represents an alternative for development and formulation of potential ingredients for functional foods.

关键词： Acinetobacter baumannii   In-vivo   Tetratrico Peptide Repeats (TPRs)   3D structure   Epitope mapping   Vaccine  

摘要： Acinetobacter baumannii is an opportunistic multidrug-resistant pathogen that causes a significant mortality rate. The proteins containing Tetratrico Peptide Repeats (TPRs) are involved in the pathogenicity and virulence of bacteria and have different roles such as transfer of bacterial virulence factors to host cells, binding to the host cells and inhibition of phagolysosomal maturation. So, in this study, physicochemical properties of a new protein containing TPRs in A. baumannii which was named PcTPRs1 by this study were characterized and its 3D structure was predicted by in-silico tools. The protein B and T cell epitopes were mapped and its vaccine potential was insilico and in-vivo investigated. Domain analysis indicated that the protein contains the Flp pilus assembly protein TadD domain which has three TPRs. The helix is dominant in the protein structure, and this protein is an outer membrane antigen which, is extremely conserved among A. baumannii strains;thus, has good properties to be applied as a recombinant vaccine. The best-predicted and refined model was applied in ligand-binding sites and conformational epitopes prediction. Based on epitope mapping results, several epitopes were characterized which could stimulate both immune systems. BLAST results showed the introduced epitopes are completely conserved among A. baumannii strains. The in-vivo analysis indicates that a 101 amino acid fragment of the protein which contains the best selected epitope, can produce a good protectivity against A. baumannii as well as the whole TPR protein and thus could be investigated as an effective subunit and potential vaccines.

关键词： 2-chloroimidazo[1,2-a]pyridine   1-azaindolizine   carbazole   chalcone   band gap   pi-conjugated compounds   chromophores  

摘要： New chalcones containing a 2-chloroimidazo[1,2-a]pyridine fragment have been synthesized, and their optical properties have been studied. The Stokes shifts, forbidden band gap widths, molar absorption coefficients, and fluorescence quantum yields have been determined on the basis of their absorption and emission spectra. Introduction of an additional thiophene fragment into the chalcone molecules produced an increase of the Stokes shift, red shift of the emission maximum, and sharp increase of the quantum yield (up to 22%). The synthesized chalcones showed high thermal stability and good film-forming properties, and films obtained therefrom exhibited an ordered structure.

关键词： Non-wood fiber   Cellulose   Hemicellulose   Pulp and papers   Morphology  

摘要： The search for non-wood fibers as alternative to the limited wood fiber resources is highly imperative in the pulp and paper-based industries. This is due to growing environmental concern as a result of excessive deforestation. This study aimed at investigating the pulp and paper potentials of pineapple crown (Ananas comosus), sandbox (Hura crepitans), pino macho (Pinus caribaea), elephant grass (Pennissetum purpureum) and teak (Tectona grandis) leaves. Chemical properties (holocellulose, cellulose, hemicellulose, ash contents, hot water and 1% NaOH solubilities) were determined using the relevant TAPPI test and chlorite methods, while the physical properties were determined after the pulping processes. Fourier transform-infrared spectroscopic (FT-IR) analyses of intrinsic functional groups of the paper sheets produced from the pulps of the waste plant leaves were determined. In addition, scanning electron microscope (SEM-EDX) analyses of the morphological characteristic and elemental compositions of the resulting hand sheet surfaces were also examined.P. caribaeahas the highest lignin (80.22 +/- 0.012%) and cellulose (72.30 +/- 0.012%) contents with lowest 1% NaOH solubility (15.20 +/- 0.05%) values.A .comosus has the highest hemicellulose (21.73 +/- 0.1%) and moisture (75.00 +/- 0.12%) contents with lowest ash values (5.01 +/- 0.15%). The fibre lengths and the Runkel ratio of the resulting pulps were of the order,A. comosus > P. purpureum > P. caribaea > H. crepitans > T. grandisandA. comosus < P. caribaea < H. crepitans < T. grandis < P. purpureumrespectively. Their surface morphologies, paper qualities and characteristics differ, but comparable with the earlier reported literatures on the pulps from wood and non-woody sources.

关键词： Low-temperature denitrification   NH3-SCR   Carbon-based catalysts   Waste bamboo   Surface functional groups  

摘要： Waste bamboo-derived activated carbon (BAC), biomass char (BBC), and nitric acid-modified BACN and BBCN supports as well as commercial activated carbon (AC) and corresponding ACN were prepared for comparative study. Their denitrification performance in 100-250 degrees C decreased as BACN > ACN > BBCN > BAC > AC > BBC. BACN and ACN were separately loaded with different MOx (M = Mn, Ce, Fe, Cu, V) by wet impregnation. M/BACN showed slightly higher NO conversion than corresponding M/ACN. Mn/BACN exhibited the best denitrification performance with NO conversion of 92% at 200 degrees C. The physicochemical properties of supports and catalysts were characterized by BET, SEM-EDS, FTIR, XRD, and XPS. The results suggested that BAC was most sensitive to HNO3 modification, thereby BACN possessed much more surface functional groups. This was the main reason for BACN exhibiting the best denitrification performance among the supports. Loading metal oxides introduced more strong active sites sharply increasing the catalytic activity, even though decreased the surface area and decomposed a few surface functional groups. Mn/BACN mainly followed the L-H mechanism at low temperature. Rich surface functional groups on BACN could promote the adsorption and activation of NH3 and NO accelerating the reaction in L-H mechanism.

关键词： Buffalo meat products   Burger   Meat batter   Meat emulsion   Mechanical work   Mixing equipment  

摘要： This work aimed to evaluate the microstructural, physicochemical and sensorial properties of buffalo meat patties produced using different mixing equipment (bowl cutter, universal mixer, and meat mixer). Scanning electron microscopy revealed a more homogenize emulsion, cohesive structure and smaller pore size of patties produced using the bowl cutter, which significantly reduced the total fluid release, water release, fat release and cooking loss as compared to the universal mixer and meat mixer. Production of the buffalo meat patties using bowl cutter also improved the moisture retention and gel strength of the patties. The patties produced using bowl cutter had the significantly highest lightness and yellowness values, while the redness was the lowest. Lower hardness, gumminess and chewiness also were observed from the patties produced using bowl cutter. Quality of the microstructural and physicochemical properties of the patties produced using different equipment can be organized as bowl cutter > universal mixer > meat mixer. Nevertheless, the sensory evaluation demonstrated a higher preference on aroma, flavour and overall acceptability of patties produced using meat mixer due to coarser and meaty texture, while the colour, tenderness, juiciness and springiness did not differ against using bowl cutter and universal mixer.

关键词： Sugarcane spirit   Ageing   Underwater   Polyphenols   Volatile fingerprinting   Colour  

摘要： The unique agricultural rum produced in Europe, Agricultural Rum of Madeira, is obtained from alcoholic fermentation and distillation of sugarcane juice, followed by cask ageing for a minimum of 3 years. For the first time, the impact of underwater bottle ageing on the maturation of this type of spirit was studied. Herein, the physicochemical properties of samples of Agricultural Rum of Madeira bottle-aged in a cellar and after 7 and 14 months on the seafloor were compared. The results revealed significant and positive changes in the organoleptic properties of the rum after 14 months of ageing on the seafloor. It was found that underwater ageing does not lead to the loss of the specific polyphenols of the cask-ageing stage (non-flavonoids, 43.53 mg/L after 14 months on the seafloor) and increases the flavonoids composition (6.88 to 21.09 mg/L after 14 months). While the acidity increased slightly, the volatile composition of the primary aromas resulting from sugarcane (terpenoids) was unchanged. Esters represented about 85% of the volatile compounds in the bottled sugarcane spirit after ageing in casks and higher concentration (increase of about 23%) were detected after underwater ageing. This study also revealed that 14 months of underwater ageing promoted a colour change to darker tones, with values close to those detected by the human eye (Delta E of 2.47). The principal component analysis highlighted the meaningful changes after 14 months on seafloor conditions, without any chemical family standing out as the most important.

关键词： Dutching   Bakery   Quality   Consumer's acceptance  

摘要： Alkalization is a crucial process during cocoa processing to reduce its bitterness, improve solubility and develop color. Alkalization can be performed out at several points of the process (nib or cake), with different agents and at various intensities. All these variables may affect cocoa properties, but also physico-chemical and sensory properties of derived products (i.e. cakes). This work aims to evaluate the impact of alkalization type (nib vs. cake), alkalizing agent (K2CO3, NaHCO3 and KOH) and process intensity (mild and strong) on the physicochemical and sensory properties of sponge cakes. For this aim, 8 different alkalized powders were industrially produced and used in the preparation of sponge cakes. Alkalizing conditions significantly affected cocoa properties (pH, color, sensory properties) and those of the corresponding cakes (cake doughs color and rheology, as well as baked cake color and texture). In general, doughs prepared with cocoas alkalized under strong conditions were a 55 % darker and a 15 % less elastic. After baking, the corresponding cakes were a 17 % darker (L*) and a 12 % harder in texture. Despite these differences, all the cakes were equally rated by consumers in sensory terms demonstrating that for this application, alkalization variables do not condition consumer acceptability.