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关键词： Prickly pear seed cake   Proteins   Albumin   Glutelin   Antioxidant   Functional properties  

摘要： Proteins were extracted from a prickly pear seed cake using the Osborne extraction method. Physico-chemical, antioxidant and functional properties of the major protein fractions (albumin and glutelin) were studied. Glutelin fraction presented good amount of proteins (60.42% dry weight) with appreciable essential amino acids content (24.45% of total amino acids). The Fourier transform-infrared spectroscopy spectra showed between similar to 1200 and 1700 cm(-1), characteristically peaks of proteins, namely, amide I, II and III for both fractions. Antioxidant activities of protein fractions were assessed in vitro through different antioxidant tests. The protein fractions exhibited good DPPH and metal scavenging activities. However, they demonstrated moderate reductive ability. Protein fractions had a minimum equilibrium surface tension at the isoelectric pH. They were characterized by interesting techno-functional properties such as emulsifying and foaming capacities which were affected by pH values. They also displayed significant water holding (480% for albumin fraction at pH 7) and oil holding (420% for glutelin at pH 7) capacities. The found results suggested that albumin and glutelin extracted from prickly pear seed cake could have important applications in food formulations. [GRAPHICS] .

关键词： Forest   Land use type   Pasture   Physicochemical soil properties   Riparian   Soil erosion  

摘要： The effects of different land-use types on physicochemical properties and erodibility indices in suitable utilization of soil are the most important issue to be investigated. That's why the current study was carried out to investigate changes in physical, chemical soil properties and erodibility indexes under different land-use types i.e., larch-fir forests, adjacent pasture, and riparian areas. Soil samples were collected from different land use in the Meydan Pond micro-basin. Five subsamples were taken at the 0–10 cm depth at five different sampling spots in each one of the three land-use systems (i.e., forest, pasture, and riparian areas). Results showed that silt content was around 38% higher in the forest soils over pasture and the riparian areas. Dispersion rate (80%) and erosion ratio (11%) were significantly higher in riparian areas over the pasture. In conclusion, pasture soils are resistant to erosion due to the higher amount of clay percentage (95%) and aggregation rate (38%) as compared to riparian areas that are more erodible. It is concluded that the river basin should be arranged according to the land capability classes’ principles to protect the soil's fertile layer from erosion to achieve the maximum productivity of crops. © 2021 The Authors

关键词： Waxy rice starch   Wheat amylose ratios   Branching enzyme   Glucoamylase   Structural and physicochemical properties  

摘要： Based on our previous study, or wheat amylose (WA) can supply an appropriate donor for branching enzyme (BE) to generate more new alpha-1, 6 branch points in waxy rice starch (WRS), sequential glucoamylase (GA) and BE were used to modify the mixtures of WRS and WA in different amylose ratios. The effects of WA on sequential GA and BE catalysis were investigated and the structural and physicochemical properties of the GABE-modified WRS/WA samples were analysed. The results indicated that after GA -> 43E treatment, the degree of branching significantly increased with increasing ratios of WRS:WA (1:0.2-1:1.2). With increasing ratios of WRS:WA from 1:0.2 to 1:0.8, short chain length distribution (DP 6-12), solubility and loss tangent increased, whereas middle chain length distribution (DP 13-24), relative crystallinity, the rate of starch retrogradation, the gelatinization temperatures and enthalpy values, as well as storage modulus and loss modulus decreased. However, as the ratios of WRS:WA continued to increase (1:1.0-1:1.2), the above results were reversed. These data demonstrated that amylose ratios in WRS:WA mixtures was closely correlated with catalytic efficiency of sequential GA and BE. The outcome would provide a new pathway for controlling amylose ratios in WRS:WA mixtures to obtain the desirable physicochemical properties of waxy rice starch-based products via enzyme modification.

关键词： Biopolymers  

摘要： Yoghurts were prepared by fermentation in the absence (control) or presence of different concentrations of inulin, tragacanth gum, or gellan gum, and effects of the biopolymers on physicochemical and sensory characteristics of yoghurts during cold storage were examined. No significant difference in pH, colour, total solid, and bacterial viability was observed among all the yoghurts prepared. Rheological analysis revealed that yoghurts prepared with biopolymers were pseudoplastic, and firmness and apparent viscosity were greater in yoghurts with added biopolymer than in control. Syneresis was weaker in yoghurts with added biopolymer, and showed a decreasing trend with biopolymer concentration but an increasing pattern with storage time due to gel shrinkage. Yoghurts with added biopolymer showed homogeneous and more compact microstructures than control. Yoghurt prepared with 0.01% tragacanth gum exhibited the best sensory scores. Results demonstrated that small amounts of tragacanth gum could effectively replace gellan gum as a thickener of synbiotic yoghurt. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： Camel beta-CN   Purification   Emulsifying properties   Antioxidant activity   Antimicrobial activity  

摘要： Emulsifying properties and in vitro antioxidant and antimicrobial activities of the isolated camel and bovine beta-casein (beta-CN) were investigated and compared. Antioxidant assay showed that both beta-CN had significant reducing power, iron chelating and antiradical activities especially for camel beta-CN. Camel beta-CN also exhibited strong antifungal activities against Aspergillus tamarii and Aspergillus sclerotiorum. The maximum emulsion activity was achieved by both beta-CN samples at pH 7.0 and 9.0 than 5.0, with higher values for the camel beta-CN. This behavior was linked to the relative high electronegative charge and interfacial properties of proteins under conditions away from their isoelectric-point as confirmed by the zeta-potential and interfacial tension measurements. Further, the stability of emulsions decreased at pH 5.0 because of the beta-CN precipitation and aggregation despite its high surface hydrophobicity. This study concluded that the camel beta-CN has antimicrobial, antioxidant, and techno-functional properties in agricultural and food industries.

关键词： polymerized whey protein   glutathione   physicochemical properties   pharmacokinetics   toxicity  

摘要： Glutathione (GSH) is a powerful antioxidant, but its application is limited due to poor storage stability and low bioavailability. A novel nutrient encapsulation and delivery system, consisting of polymerized whey protein concentrate and GSH, was prepared and in vivo bioavailability, antioxidant capacity and toxicity were evaluated. Polymerized whey protein concentrate encapsulated GSH (PWPC-GSH) showed a diameter of roughly 1115 +/- 7.07 nm (D-50) and zeta potential of 30.37 +/- 0.75 mV. Differential scanning calorimetry (DSC) confirmed that GSH was successfully dispersed in PWPC particles. In vivo pharmacokinetics study suggested that PWPC-GSH displayed 2.5-times and 2.6-fold enhancement in maximum concentration (C-max) and area under the concentration-time curve (AUC) as compared to free GSH. Additionally, compared with plasma of mice gavage with free GSH, significantly increased antioxidant capacity of plasma in mice with PWPC-GSH was observed (p < 0.05). Sub-chronic toxicity evaluation indicated that no adverse toxicological reactions related to oral administration of PWPC-GSH were observed on male and female rats with a diet containing PWPC-GSH up to 4% (w/w). Data indicated that PWPC may be an effective carrier for GSH to improve bioavailability and antioxidant capacity.

关键词： Stabilitystability   Material science   Spectroscopy   Raw materials   Cell culture   Physico-chemical properties   Formulation   Chemically defined media   Cell culture media   Raw material variation  

摘要： Growth of mammalian cells in the production of biotherapeutics often require the benefits of chemically defined media (CDM). Storage, handling and stability advantages of CDM powders govern the preponderance of their use across the industry. Physico-chemical property lot-to-lot variation of these multicomponent powders, however, continues to be a challenge. Process imposed degradation of amino acids and vitamins, for example, can influence cell density, specific titer, and the quality profile of the molecule expressed due to the lack of process understanding and suitable mitigation controls. Such degradation can materialize in either their manufacture or in downstream media dissolution steps. Colorimetry, in lieu of visual appearance, can be an effective surveillance method for the direct assessment of CDM quality as color change is indicative of chemical-physical variations. This work describes a series of studies aimed to establish relationships between quantitative color change and physico-chemical attribute variation of glucose-free and glucose-based powders. The results illustrate color change is indicative of amino acid glycation, vitamin degradation and particle size shifts. These relationships enable a colorimetric control strategy for the sensitive and rapid detection of relevant CDM variation to drive additional targeted assessments to improve the productivity and robustness of cell culture processes. (C) 2020 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.

关键词： Ramie   Starch   Morphology   Component   Structure   Properties  

摘要： A new starch was isolated from ramie root, and its physicochemical properties were investigated. Ramie dry root contained 45.9% starch. Starch had truncated, ellipsoidal, and spherical granule shapes with size from 7 to 30 mu m and D[4,3] about 14.1 mu m. Starch contained 38.9% apparent amylose content and 22.4% true amylose content, exhibited B-type crystallinity, and had 26.6% relative crystallinity, 0.82 ordered degree, and 9.2 nm lamellar thickness. Starch had 71.8 degrees C gelatinization peak temperature and 15.6 J/g gelatinization enthalpy, and exhibited 31.4 gig swelling power and 17.1% water solubility at 95 degrees C. Starch had peak, hot, breakdown, final, and setback viscosities at 3048, 2768, 279, 4165, and 1397 mPa s, respectively, and showed peak time at 4.36 min and pasting temperature at 75.0 degrees C. The native, gelatinized, and retrograded starches contained 15.1%, 94.0%, and 86.5% rapidly digestible starch and 83.3%, 4.0%, and 10.7% resistant starch, respectively. Compared with potato and rice starches, ramie starch was somewhat similar to potato starch but significantly different from rice starch in starch component, crystalline structure, and functional properties. Therefore, ramie starch exhibited the potential to be used as a thickening agent, resistant-digesting food additive, and alternative to potato starch in food and nonfood industries. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Lentinula edodes   pre-cutting   combination order   vacuum freeze-drying combined with hot air drying   drying quality  

摘要： BACKGROUND Combination drying is recognized as an energy-efficient method utilized for dry product processing, and proper order of combination is a critical factor determining the effectiveness of the technique. In this study, hot air drying (HD), vacuum freeze-drying (VFD), and combination drying with different orders (HD-VFD and VFD-HD) are performed on wholeLentinula edodesand pre-cut (half-cut and quarter-cut)L. edodes. The effects of various cutting and drying approaches on drying characteristics, physicochemical properties, and microstructures of driedL. edodeswere investigated. RESULTS The longest processing time required to dry the wholeL. edodesby VFD was 25 h. In contrast, the pre-cutting treatment and combination drying certainly shortened the drying time. Compared with HD, use of VFD-HD and VFD significantly decreased the shrinkage ratio, hardness, and discoloration of dried products but increased the rehydration capacity, nutrient retention, and porous microstructure. Interestingly, switching the order of combination drying provoked entirely different drying effects. Specifically, HD-VFD triggered negative effects on the shrinkage and color of dried mushrooms, and its appearance color was similar to HD-treated samples. Moreover, pre-cutting dramatically enhanced the protein content of HD-treated mushrooms, and the quarter-cut samples obtained the highest level (21.69 g kg(-1)dry basis) among the three types of cutting. CONCLUSIONS The driedL. edodesprocessed through pre-cutting and combination drying (VFD-HD) have optimal industrial quality, accompanied by shorter processing time. (c) 2020 Society of Chemical Industry

关键词： Ligands  

摘要： We report a rare example of the direct alkylation of the surface of a plenary polyoxometalate cluster by leveraging the increased nucleophilicity of vanadium oxide assemblies. Addition of methyl trifluoromethylsulfonate (MeOTf) to the parent polyoxovanadate cluster, [V6O13(TRIOL(R))(2)](2-) (TRIOL = tris(hydroxymethyl)methane;R = Me, NO2) results in functionalisation of one or two bridging oxide ligands of the cluster core to generate [V6O12(OMe)(TRIOL(R))(2)](1-) and [V6O11(OMe)(2)(TRIOL(R))(2)](2-), respectively. Comparison of the electronic absorption spectra of the functionalised and unfunctionalised derivatives indicates the decreased overall charge of the complex results in a decrease in the energy required for ligand to metal charge transfer events to occur, while simultaneously mitigating the inductive effects imposed by the capping TRIOL ligand. Electrochemical analysis of the family of organofunctionalised polyoxovanadate clusters reveals the relationship of ligand environment and the redox properties of the cluster core: increased organofunctionalisation of the surface of the vanadium oxide assembly translates to anodic shifts in the reduction events of the Lindqvist ion. Overall, this work provides insight into the electronic effects induced upon atomically precise modifications to the surface structure of nanoscopic, redox-active metal oxide assemblies.