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关键词： Coffee quality   Specialty coffee   Titratable acidity   Brewing temperature   Coffee flavor  

摘要： The effect of coffee bean quality (specialty and regular) and brewing method (cold and hot) on the sensory profile and physicochemical characteristics of coffee beverages was studied. Cold brew was prepared by immersion and hot brew coffee by French Press. Total dissolved solids (TDS), titratable acidity (TA), caffeine, trigonelline, 4 and 5- caffeoylquinic acids were quantified by instrumental methods, volatile compounds by GC-MS, and the coffee flavor was through quantitative sensory evaluation. Coffee beverages were more differentiated by brewing method than by the coffee bean quality used in the preparation. Cold brew coffees were mainly associated with volatile 2-methyl-butanal, 5-methyl furfural, and dihydro-2-methyl- 3 (2H) -furanone. Hot brew coffee beverages were identified with some specific furans and 2-methoxy-4-vinylphenol. No significant differences were found in TDS, caffeine, trigonelline, 4 and 5 caffeoylquinic acids. A higher TA was observed in hot coffee beverages than in cold brew coffees. Regular bean quality promoted undesirable sensory attributes in both cold and hot brew beverages. However, these attributes were perceived in higher intensity in hot brew coffee beverages. Thus, differences in brewing methods affect the extraction of the chemical compounds present in different coffee bean quality, translating into variations in the sensory profile.

关键词： Dendrimers   Drug delivery   Drug interactions   Anti-cancer drugs   Gene delivery  

摘要： Purpose of Review Drug and gene deliveries are crucial aspects in biomedical application as they stimulate biological response of the body to elicit a therapeutic effect. It is seen that drugs, their formulations and the route of administrations, play a vital role in enhancing therapeutic effect onto the desired cellular or intracellular target. But, conventional drug forms suffer from poor pharmacodynamics and pharmacokinetics profile. For this purpose, different nanosized dendrimer-based drug and gene delivery systems and the interactions between dendrimers and guest molecules have been reviewed. Recent Findings Dendrimers as drug and gene carriers enhance the systemic blood circulation time, biocompatibility, and reduce toxicity. While, on one hand, non-covalent interactions of dendrimer-drug (physical encapsulation) improves drug solubility, on the other hand, electrostatic interactions with charged molecule encourages endosomal escape. Covalent association through various physiologically labile bonds or cleavable linkers can achieve controlled release and targeted delivery of the therapeutic moiety. Summary Dendrimers can act as versatile tools for delivery of nucleic acids, drugs, vaccines for different diseases via different administration routes.

关键词： Carotenoids   carrier materials   carrot juice   spray drying  

摘要： The objective of this study was to determinate the influence of carrier addition and spray drying temperatures (160 or 200 degrees C) on physicochemical properties of spray-dried carrot juice powder. As carriers, maltodextrin and gum Arabic in different proportions were used. In powders were determined the following: moisture content, water activity, apparent density, size of particles, colour and carotenoids content. The content of carotenoids in powders prepared from solutions with juice to carrier ratio 2:3 was 324.3-406.6 mg/kg d.m., while in powders with a J:C = 3:2 values ranged from 576.7 to 637.7 mg/kg d.m. The highest content of carotenoids and the most yellow colour were observed in powders with 1:3 gum Arabic to maltodextrin ratio. Powders with the highest amount of gum Arabic have the highest diameter and the lowest water activity. High inlet temperature caused brighter colour of powders, higher dry matter content, lower water activity and apparent density of powders.

关键词： Nanocellulose   Pentyl valerate   Candida rugosa lipase   Polyethersulfone   Silica   Oil palm leaves   Taguchi orthogonal design  

摘要： A greener processing route to replace the current environmentally-unfriendly esterification technique to produce biofuels such as pentyl valerate (PeVa) was explored. This study statistically optimized the covalent immobilization of Candida rugosa lipase (CRL) onto biomass-based nanocellulose-silica (NC-SiO2) reinforced polyethersulfone (PES) membrane to synthesize PeVa. Raman spectroscopy, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and atomic force microscopy of NC-SiO2-PES/CRL proved that CRL was successfully conjugated to the membrane. The optimized Taguchi Design-assisted immobilization of CRL onto NC-SiO2-PES membrane (5% glutaraldehyde, 4 h of immobilization, 20 mg/mL CRL concentration, 40 degrees C and pH 5) gave 90% yield of PeVa in 3 h. The thermal stability of NC-SiO2-PES/CRL was similar to 30% greater over the free CRL, with reusability for up to 14 successive esterification cycles. In a nutshell, the greener NC-SiO2-PES membrane effectively hyperactivated and stabilized the CRL for the esterification production of PeVa. This research provides a promising approach for expanding the use of sustainably sourced NC and SiO2 nanoparticles, as fillers in a PES for improving CRL activity and durability for an extended catalytic process.

关键词： Flax  

摘要： Increasing environmental concern has put forward the use of flax fibers instead of glass fibers in composite materials. However, durability performances of these bio-fibers remain one of their main issues. This study focuses on the hydrothermal aging of flax fibers. Flax tows were immersed in distilled water at a temperature of 80 degrees C for different durations. The effect of the hydrothermal aging on mechanical properties of flax tows was evaluated. Results showed a strong decrease in the maximal strength and the stiffness by 31% and 49%, respectively, until one week of aging. Multi-scale analyses were realized to explain these evolutions. Morphological characterization highlighted a washing of fiber surfaces during the hydrothermal aging, extracting amorphous components as pectins, lignins and amorphous hemicelluloses from cortical tissues. We showed that this morphological evolution impacted the fiber crystallinity. Based on a mechanical analysis, we showed that amorphous components extraction may be at the origin of the material softening. Moreover, the amorphous phase in particular the natural binder pectin would play a major role in the fiber stiffness but does not modify the flaws at the origin of failure.

关键词： Diesel engine   Dual-fuel mode   Emission catalysts   Lower/higher alcohols   Physicochemical properties of particulate matter   Soot  

摘要： The literature reveals that fossil fuels will continue to be the main energy source for transportation fleets up to 2050, despite their non-renewability and the emissions of pollutants resulting from their use. Until the full adoption of non-fossil and zero-emission vehicles (e.g., electric vehicles), the application of renewable liquid fuels could be the best choice due to the latter's positive effects such as reduced consumption of fossil fuels and reduced emissions of pollutants. Alcohols, among others, have been widely tested as alternative fuels in diesel engines, however, there is no comprehensive information about their impacts on particulate matter (PM) which has a direct influence on human health, the environment, and emission catalyst's efficiency. This review comprehensively explores the impact of lower/higher alcohols, from methanol to decanol, in dual-fuel mode on the PM physicochemical properties emitted from diesel engines under different alcohol ratios and operating conditions. It is observed that alcohols change the PM physical properties by reducing primary particle size/ number, radius of gyration, fractal dimension, and fringe length and increasing fringe separation distance and tortuosity compared to those of diesel PM. Regarding the chemical properties, alcohols reduce polycyclic aromatic hydrocarbons, benzo[a]pyrene equivalent, organic carbon (OC), elemental carbon (EC), ions, and soot ignition temperature and increase OC/EC ratio and soot oxidation reactivity. Thus, each 10% of alcohol, by volume, has the potential to reduce PM mass, number, and size by about 17, 20, and 10%, while lower alcohols and blended mode have more impact than higher alcohols and fumigation mode, respectively.

关键词： Tea residue   High-temperature cooking assisted enzymatic   method   Structural characteristics   Physiochemical properties   Functional properties  

摘要： The research aimed to assess the effects of high-temperature cooking assisted enzymatic method on the structural, physicochemical and functional properties of soluble dietary fiber (SDF) from tea residue (GM-SDF). Under the optimal extraction conditions obtained by response surface methodology, the GM-SDF yield was significantly higher than that of untreated tea residue (U-SDF). It could be found results showed that GM-SDF possessed more hydrophilic groups, higher crystallinity, as well as a looser and more complicated structure by FTIR, XRD and SEM analysis. Besides, the differences in monosaccharide composition and molecular weight between U-SDF and GM-SDF were observed. Additionally, physicochemical properties analysis showed that water holding capacity, oil holding capacity and water swelling capacity of GM-SDF increased by 73.1%, 57.2% and 81.8% than that of U-SDF, respectively. Moreover, compared with U-SDF, GM-SDF exhibited higher adsorption capacity of glucose, sodium cholate, cholesterol and capacity of delaying glucose diffusion and dialysis. Furthermore, the inhibitory effect of GM-SDF on alpha-amylase was similar to that of acarbose. To sum up, the study showed that hightemperature cooking assisted enzymatic method can effectively extract dietary fiber from tea residue and improve the physicochemical and functional properties, which possesses great potential for application in functional food.

关键词： Dairy products  

摘要： In this study, five types of yogurt samples were produced with different concentrations (0% [control group], 0.05%, 0.10%, 0.15%, and 0.20%) of Mentha pulegium L. (pennyroyal) powder (MPP) and their physicochemical, textural, sensory, and microbiological properties were investigated on the 1st, 7th, and 14th days of storage. Increasing concentrations of MPP affected the L* and a* values of yogurt considerably. About 0.05% and 0.15% MPP addition improved the textural properties of yogurt samples. The higher the MPP concentration, the lower the lactic acid bacteria counts were;however, the numbers were still over the minimum requirement for yogurt. Fibrous and filamentous structures in yogurt samples with MPP were monitored by scanning electron microscopy. Consequently, it can be stated that MPP can be successfully added to yogurt. Furthermore, considering sensory evaluations, it would be plausible to say that yogurt samples containing MPP up to 0.10% may have market potential in the future. Practical applications Currently, there is a growing trend of healthy and functional foods throughout the world. Dairy product, especially yogurt, is one of the best conveyors for the functional ingredients. Therefore, enrichment of yogurt with different herbs/spices/fruits attracts great attention among consumers. Mentha pulegium L. (MPP, pennyroyal) is a functional herb and a good candidate to be utilized in yogurt with its dense aromatic properties. This study presents the first findings of MPP incorporation into yogurt. MPP addition up to 0.10% was found acceptable considering textural and organoleptic properties. Lactic acid bacteria counts in yogurt samples slightly decreased with increasing concentrations of MPP. The results of the research showed that MPP can be utilized in yogurt up to 0.10% without any problems.

关键词： Stable isotopes   Hydrochemistry   Multi-tracers   Groundwater   surface-water relations   France  

摘要： Groundwater extracted from the Barthelasse Island aquifer, surrounded by the river Rhone (southeastern France), contributes to the drinking water supplies of 180,000 inhabitants. Owing to its location close to the river and the presence of two backwaters (oxbow lakes), the pumped groundwater is highly vulnerable to river pollution. A pumping test was conducted over 24 h to analyse and quantify the water exchange processes between the river, backwaters and groundwater. During the pumping test, isotopic (delta O-18, delta H-2 and Rn-222), hydrochemical and hydrophysical monitoring of the groundwater was undertaken. Hydraulic heads were measured in pumping wells and at a piezometer located between the wells. Discrete water samples were collected at several observation points in the field, including the backwater and river. The results show mixing between three end-members, as defined by the deuterium excess and silica concentration, led by river Rhone water which had been affected by water-rock interactions over time and mixing with surface evaporated waters. The pumped water resulted from mixing between three end-members, all of which depended on the river Rhone but differed in terms of residence time in the system. Although the groundwater pumping wells are close to each other (<70 m) and have similar depths, the changes in the contributions from end-member waters at each well were different during the pumping test. Comparing isotopic tracers and geochemistry made it possible to quantify the different hydrological compartments that contribute to the groundwater pumped from the boreholes, which is critical in constructing a conceptual flow model.

关键词： Handroanthus impetiginosus   Bigoniaceae   Red lapacho tree   Review   Naphthoquinones   beta-Lapachone  

摘要： beta-Lapachone is an ortho-naphthoquinone originally isolated from the heartwood of Handroanthus impetiginosus and can be obtained through synthesis from lapachol, naphthoquinones, and other aromatic compounds. beta-Lapachone is well known to inhibit topoisomerase I and to induce NAD(P)H: quinone oxidoreductase 1. Currently, phase II clinical trials are being conducted for the treatment of pancreatic cancer. In view of everincreasing scientific interest in this naphthoquinone, herein, the authors present a review of the synthesis, physicochemical properties, biological activities, and toxicity of beta-lapachone. This natural compound has shown activity against several types of malignant tumors, such as lung and pancreatic cancers and melanoma. Furthermore, this ortho-naphthoquinone has antifungal and antibacterial activities, underscoring its action against resistant microorganisms and providing anti-inflammatory, antiobesity, antioxidant, neuropmtective, nephroprotective, and wound-healing properties. beta-Lapachone presents low toxicity, with no signs of toxicity against alveolar macrophages, dermal fibroblast cells, hepatocytes, or kidney cells.