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关键词： Anacardium occidentale L   Nanotechnology   Zein   Nanoparticles   Anacardic acid   Antimicrobial  

摘要： Anacardic acid (AA) has gained interest regarding its extraordinary antimicrobial activity. Nanotechnology based delivery systems are a modern approach to improve both pharmacological and functional properties of therapeutic agents. In this paper we aimed to design and characterize AA loaded-zein nanoparticles and evaluate its antimicrobial efficiency in vitro using microdilution and antibiofilm assays. AA nanoparticles were spherical, stable, with an average size of 381.6 nm and negative zeta potential. The saturation transfer difference-NMR analysis demonstrated the association of zein and AA in two different conformations, enlightening its enhanced pharmacological activity. Bacteriostatic concentrations were 0.05 and 3.12 mu g/ml for Staphylococcus aureus and Pseudomonas aeruginosa, while bactericide activity was observed only for S. aureus at 0.2 mu g/ml. Fungistatic/fungicide concentrations for Candida rugosa were 1.17/2.34 mu g/ml, for Candida albicans and Candida parapsilosis 2.34/4.69 mu g/ml and for Candida tropicalis, Candida jardinii, Candida glabratta and Candida auris 4.69/4.69 mu g/ml. Furthermore, nanoencapsulated AA was more efficient in reducing S. aureus and C. albicans biofilms viability than AA solution, while they presented a similar inhibition against P. aeruginosa biofilm. Therefore, AA loaded-zein nanoparticles could represent an alternative for potential applications where the low concentrations of this phytochemical are useful to prevent or treat bacterial and fungical infections. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Mango butter   Sorbitan monopalmitate   Crystal modifier   Crystallization kinetics   Two-stage crystallization  

摘要： The present study reports the effect of sorbitan monopalmitate (SM) as a crystallization modifier on the physicochemical properties of mango butter (MB). The concentration of SM was varied in the range of 1 and 5 wt%. The addition of SM promoted the aggregation of globular MB crystals. The FTIR patterns did not show any significant changes when SM was added. XRD and DSC analyses confirmed the crystallization of MB crystals in stable beta' and beta (V) polymorphic states. However, SM also introduced imperfections in the crystal lattices of MB. Among all formulations, M2 (SM;1% w/w) possessed a mechanically stable network structure. The crystallization rate of MB was tailored by SM in a concentration-dependent manner. The solid content was highest in M4 (SM;5% w/w) at 10 degrees C and 30 degrees C among all the oleogels. In gist, SM in manageable quantities can be utilized for preparing custom-tailored MB-based products.

关键词： Density   Viscosity   Sound velocity   Refractive index   Blended-amines  

摘要： We report the density, viscosity, sound velocity, and refractive index experimental data of four silane-amine blended systems viz. (1) 3-aminopropyl triethoxysilane (TESA) + N-(2-aminoethyl) piperazine (AEP), (2) 3-aminopropyl triethoxysilane (TESA) + 2-methyl-1-propanol (AMP) (3) 3-aminopropyl triethoxysilane (TESA) + Methyldiethanolamine (MDEA) and (4) 3-aminopropyl triethoxysilane (TESA) + Diethanolamine (DEA). The temperature range for all the measurements is (298.15-333.15) K up to a mole fraction of 0.2 of TESA in the solution. The physicochemical properties were well fitted against the first principle and artificial neural network models. We further calculated key properties for CO2 capture such as diffusivity in CO2, isentropic compressibility, thermal expansion coefficients, Gibb's free energy, entropy, and enthalpy of activation. The data collected fromthiswork could contribute to further detailed kinetic analysis of CO2 absorption over these capturing solvents (C) 2021 Elsevier B.V. All rights reserved.

关键词： Geological materials   Soils   Adsorption   Probes   Materials  

摘要： The goal of this study was to determine the physicochemical properties of a variety of geologic materials using inverse gas chromatography (IGC) by varying probe gas selection, temperature, carrier gas flow rate, and humidity. This is accomplished by measuring the level of interaction between the materials of interest and known probe gases. Identifying a material's physicochemical characteristics can help provide a better understanding of the transport of gaseous compounds in different geologic materials or between different geological layers under various conditions. Our research focused on measuring the enthalpy (heat) of adsorption, Henry's constant, and diffusion coefficients of a suite of geologic materials, including two soil types (sandy clay- loam and loam), quartz sand, salt, and bentonite clay, with various particle sizes. The reproducibility of IGC measurements for geologic materials, which are inherently heterogeneous, was also assessed in comparison to the reproducibility for more homogeneous synthetic materials. This involved determining the variability of physicochemical measurements obtained from different IGC approaches, instruments, and researchers. For the investigated IGC-determined parameters, the need for standardization became apparent, including the need for application-relevant reference materials. The inherent physical and chemical heterogeneities of soil and many geologic materials can make the prediction of sorption properties difficult. Characterizing the properties of individual organic and inorganic components can help elucidate the primary factors influencing sorption interactions in more complex mixtures. This research examined the capabilities and potential challenges of characterizing the gas sorption properties of geologic materials using IGC.

关键词： Enzymatic interesterification   Specialty fats   Oxidative stability   Properties  

摘要： Interesterification is widely employed as an effective technique to modify oils and fats. This study utilizes palmbased oil (palm olein: palm kernel oil: palm stearin, 5:3:2, w/w/w) as the raw material for the interesterification process performed in a pilot-scale packed bed reactor. Enzymatic interesterification (EIE) was catalyzed by Lipozyme TL IM (813.0 g) at 60 degrees C with reaction flow rate of 100 mL/min. Chemical interesterification (CIE) was catalyzed using sodium methoxide (0.3 wt%) as catalyst at 105 degrees C for 30 min. The results showed that the EIE fats had lower solid fat content tendency compared to that of CIE fats. The crystallization onset temperature was higher in EIE fats (23.09 degrees C) compared to that of CIE (19.08 degrees C). The results were consistent with the crystallization kinetics whereby the Avrami K constants of EIE fats were higher than that of CIE fats at various temperatures, indicating rapid crystallization and instant nucleation. Linear growth mechanism was dominant and the crystals formed were smaller in size as observed using polarized light microscope. The interesterified fats exhibited the presence of beta and beta-crystals. While most of the tocopherol content was retained after EIE (386.18 ug/g), the molecular distillation process reduced the tocopherol concentration (110.01 ug/g) which consequently affected the oxidative stability. The findings in this work contribute to the fundamental understanding on the differences between CIE and EIE fats and provides data to support the preparation of modified fats via EIE that shows great potential as a controllable technique for industrialization.

关键词： CD-MOFs   gamma-Cyclodextrin   Curcumin   Stability   Controlled release  

摘要： A safe and biodegradable gamma-cyclodextrin-metal-organic-frameworks (gamma-CD-MOFs) was successfully synthesized by using an improved hydrothermal method. In this study, curcumin (Cur) was chosen for testing the encapsulation stability and release performance of gamma-CD-MOFs. Results of the crystal structure measurement indicated that the encapsulated curcumin within gamma-CD-MOFs via van der Waals forces, hydrophobic interactions and hydrogen bonding was failed to disturb the inherent microtopography and crystallinity of gamma-CD-MOFs. Compared to individual gamma-CD, the gamma-CD-MOFs exhibited improved loading capacity, physicochemical stability as well as controlled-release property in simulated digestion, and hence can be regarded as effective carriers for curcumin. Curcumin-loaded gamma-CD-MOFs with a Cur : gamma-CD-MOFs mass ratio of 2:3 (Cur-CD-MOFs/3), which showed the highest encapsulation efficiency (67.31 +/- 2.25%), improved physicochemical stability and controlled-release performance, was selected for further research and industrialization. Our results demonstrate that gamma-CD-MOFs can be regarded as a promising novel carrier for the delivery of curcumin or other hydrophobic nutraceuticals.

关键词： Sesame oil   Isopropyl myristate   Carbopol 974P (R)   Polycarbophil   Emulsion   Sol-gel transition  

摘要： Emulgels can be prepared easily and provide the efficient drug release of hydrophilic and hydrophobic drugs. In this work, emulgel systems containing poloxamer 407, Carbopol 974P (R) or polycarbophil, sesame oil or isopropyl myristate ere prepared using Quality by Design and the physicochemical damages were investigated regarding the preliminary stability studies. The physicochemical stability was assessed according to six freeze-thaw cycles, where the appearance, phase separation (fracture), droplet size and instability index were determined. The stable formulations ere further characterized by sol-gel transition temperature. The freeze-thaw cycles and analytical centrifuging showed consistent and complementary results evidencing that lower concentration of bioadhesive polymers fostered the phase separation. Formulations showed to be polydisperse systems with droplet size dependent of the freeze-thaw cycles. The stable systems were selected by Quality by Design approach, and they showed suitable gelation temperature for future pharmaceutical and biomedical applications. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Tamarind seed polysaccharides modification   Structural characteristics   Pasting properties   Freeze-thaw stability  

摘要： In this work, structural characteristics of TSPs treated by high-pressure homogenization (HPH) and their effects on physicochemical properties of corn starch were analyzed. HPH induced monosaccharides change, Gal/Glc ratio decrease from 0.32 to 0.25, and molecular weight (Mw) decrease from 10.55 to 4.47 ? 105 Da through damaging glycosidic linkages in the backbone and side-chain of TSPs. Furthermore, 90 MPa homogenized TSP (higher Gal removal) showed inhibitory effects on starch paste retrogradation, and TSPs with a lower Mw (homogenized at 60 and 90 MPa) could limit water precipitation during the long-term storage. Moreover, Mw and Gal/Glc ratio were the major factors for the determined effects of TSPs on physicochemical properties of corn starch. The results could provide new insights into the relationship between TSP structure and their effects on the physicochemical properties of starch.

关键词： Good-quality indica rice   Alternate wetting and drying   Starch structure   Thermal properties   Pasting properties  

摘要： The effects of water irrigation management including conventional irrigation (CK), constant flooding irrigation (CFI) and alternate wetting and drying (AWD) on starch structure and physicochemical properties of two indica rice cultivars with good- and poor-quality were evaluated in the field condition with two years. The results showed that AWD could significantly increase peak viscosity, breakdown and gelatinization temperature, decreased setback and gelatinization enthalpy in two indica rice cultivars. However, starch granule size and amylopectin chain length distribution were differed the trends in the rice cultivars and treatments. AWD reduced starch granules size and amylopectin short chain, especially for large starch granules, but increased medium and long chain, which might contribute to better thermal stability and pasting viscosity for good-quality cultivar. Our study indicated that water irrigation management affected starch structure and physicochemical properties of indica rice starch, and would provide favorable information for improvement of rice starch in food industry.

关键词： Whey protein isolate   Gellan   Protein-polysaccharide conjugate   Emulsion   beta-Carotene   Bioaccessibility  

摘要： This study aimed to examine the effect of whey protein isolate-low acyl gellan gum (WPI-GG) conjugate on the physicochemical properties and digestibility of beta-carotene-loaded oil-in-water emulsions. The WPI-GG conjugate stabilized emulsions had lower droplet sizes with more homogenous distribution, more negative surface charge, and higher interfacial protein concentration and viscosity, compared to those stabilized by WPI-GG mixture and WPI. The emulsion droplets coated by the conjugate were also generally more stable to environmental stresses (i. e., storage, pH changes, ionic strength, freeze-thaw cycles, and thermal treatment) along with higher beta-carotene retention than other systems. The stability to droplet aggregation during in vitro digestion was remarkably increased for the conjugate-stabilized emulsion. However, the beta-carotene bioaccessibility was significantly affected when the conjugate was used to stabilize the emulsions, likely due to the thick interfacial layer, high viscosity, and negative charge of the corresponding emulsions that could inhibit droplet digestion and mixed micelle formation.