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关键词： Cold-pressed sesame cake   Ultrasonic pre-treatment   Protein   Lignans   Amino acids   Physicochemical properties  

摘要： Sesame is an oil crop with high nutritional value. Protein is one of the main ingredients of sesame, however research on protein of cold-pressed sesame cake is limited. This study aimed to investigate the effects of ultrasonic pre-treatment (UPT) on physicochemical properties of proteins (yield, solubility, amino acid composition, surface properties, structural and thermal stability) extracted from the cold-pressed sesame cake, after removing lignans by ultrasonic-assisted extraction. By comparison, the extraction yield of protein was significantly (p < 0.05) increased from 22.24% (without UPT) to 25.95% (with UPT), while the purity (54.08% without UPT, 55.43% with UPT), total amount of essential amino acids (22.48% without UPT, 23.10% with UPT) and nonessential amino acids (37.48% without UPT, 36.54% with UPT) were not significantly influenced. Besides, UPT slightly reduced the solubility, foaming capacity and stability (FC and FS) of protein. In addition, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and thermal stability (TG) analysis demonstrated that UPT could disorder and loose protein molecular structure, resulting in the change of morphology, secondary structure and thermal stability. In conclusion, this study provides a way for the separation and future application of sesame cake protein. UPT is a good option to remove the lignans from sesame cake proteins.

关键词： Highland barley   Germination   Physicochemical   Polyphenol   UHPLC-Q-TOF  

摘要： Highland barley (Hordeum vulgare. L) is the staple food resource in the Qinghai-Tibet Plateau of China. The aim of this study was to investigate the effect of germination on the polyphenol profile, antioxidant activities, and physicochemical properties of three color cultivars of highland barley. Ultra-high-performance liquid chromatography coupled to electrospray ionization-time of flight mass spectrometry was applied to separate and characterize 23 polyphenols in barley extract before and after the germination. The heatmap plot revealed that ten polyphenols were up-regulated, and seven were down-regulated. In the physicochemical characterization studies, the water-holding capacity, water-solubility index, fat-absorption capacity, and foaming capacity of germinated barley flours were increased significantly. Moreover, germination also resulted in a significant increase in higher transition temperatures values and lower enthalpy values in these barley flour. Our results may help in understanding the influence of germination on the functional properties of highland barley and choosing appropriate applications to promote the utilization of germinated highland barley in the food industry.

关键词： Lactose hydrolysed milk   Maillard browning   Enzymes   Detection techniques   Mitigation strategies  

摘要： Background: Lactose hydrolysed milk and milk products have emerged as a boon to lactose intolerant people worldwide, however, many challenging technical issues are faced during their processing. These low lactose products suffer from many drawbacks which tend to reduce consumer acceptability e.g. Maillard browning due to increased monosaccharides content. Scope and Approach: The literature on Maillard reaction in milk and food products is quiet extensive, however, it lacked emphasis on browning in lactose hydrolysed milk and milk products. Understanding the factors which accelerate the rate of Maillard browning will result in effective mitigation. Key Findings and Conclusions: Preparation of lactose hydrolysed milk products and problems associated with enhanced Maillard reaction have been dealt in detail. Further, various feasible strategies to mitigate Maillard browning have also been discussed in this review.

关键词： Oxidized and amide modified carbon nanotubes   Electrophoretic deposition   Work function   Antibacterial   Anticancer   Biocompatibility   Biomedical applications  

摘要： Physicochemical, electrochemical and biological performance of 4 types of all-carbon nanotube layers was studied. Higher oxidation state of carbon was responsible for micro-scaled uniformity of the layers and excellent electrical conductivity, while nitrogen containing functional groups yielded materials with anisotropy similar to natural tissues and reduced work function. All materials were cytocompatible with mammalian fibroblasts (viability >80%, cytotoxicity <3% at day 7) and human dermal fibroblast (viability of cells >70% at day 1), while reducing bacterial and cancer cells proliferation without adding any drug. After 8 h culture, a similar to 50% depletion in the number of Gram-positive bacteria was observed on materials with lower work function, while Gram-negative bacteria were more sensitive towards carbon coordination number and presence of nitrogen atoms (cell depletion of up to 48% on amidized carbon nanotubes). After 1-day culture, >80% reduction in the melanoma cells number, connected with enhanced production of reactive oxygen species (ROS) was observed. All-carbon nanotube layers decreased bacteria and cancer cell functions without negatively influencing mammalian cells nor using drugs and we believe that this can be explained by various sensitivity of the tested cells towards exogenous ROS overproduction. As the concerns over implant-related infections as well as rates of antibiotic-resistant bacteria and chemotherapeutic-resistant cancer cells are growing, such materials should pave the way for a wide range of biomedical applications.

关键词： Cost effectiveness  

摘要： The present research aims to elucidate the effect of lactic acid concentration on the extractability and physicochemical properties of cobia (Rachycentron canadum) skin collagen. The cobia skin acid-soluble collagen (ASC) was isolated using different concentrations of lactic acid (0.5 M and 1.0 M) and characterized on its extractability and physicochemical properties. The extract using 0.5 M lactic acid gives a higher yield compared to using 1.0 M lactic acid. The moisture, protein, fat, and ash content of cobia skin ASC extracted using 0.5 M was higher than extracted using1.0 M lactic acid. The functional group present in both extracts was amide A, amide I, and amide III. Both extracts at different lactic acid concentrations showed decreasing on relative viscosity with temperature increased. Thus, different extractability and physicochemical properties of cobia skin ASC extracts exhibits based on the lactic acid concentration and it would produce collagen with multi potential application. Practical applications The best way to minimize the environmental contaminations from fish processing industrial waste and provide the economic value to waste materials is collagen production. Collagen prepared from fish skin can utilize in various purposes as biopolymer. Extraction of collagen from a chemical method by utilizing organic acid like acetic acid, chloroacetic acid, citric acid, lactic acid, or inorganic acid like hydrochloric acid is more suitable due to low-cost effective which compared to enzyme like pepsin. The present study focused on the utilization of lactic acid at different concentration produces collagen with multipotential application with extractability and physicochemical properties.

关键词： Liquids  

摘要： The study was performed to investigate some changes in physicochemical characteristics and ginsenoside profiles of Korean ginseng after being subjected to immersion in fermented tea liquid (FTL) [at a ratio of ginseng powder: FTL;1:4, 1:6, and 1:8, w/w] and steam treatments (with and/or without steam). The ratio at 1:4 w/w showed the highest yield of bioactive components and was, therefore, selected to evaluate the effects of steam conditions [temperatures (60, 80, and 100 degrees C) and times (1, 2, and 3 hr)]. The sample treated with FTL, regardless of the steam treatment, had darker color and higher antioxidant activity (IC50 for DPPH) than those of the control. The minor ginsenoside content increased at higher steaming temperature (100 degrees C) and longer time (3 hr). Enhancing bioactive components of Korean ginseng by incorporating with FTL could lead to further development of various new ginseng products and might increase their health benefits for consumer's health. Practical applications This study demonstrated that some characteristics of Korean ginseng can be altered by immersion in fermented tea "Miang" liquid (FTL) and steam treatment. The immersion treatment significantly increased antioxidant activity of Korean ginseng. Minor ginsenosides including Rh1, Rk3, Rh4, Rg3, Rk1, and Rg5 were generated when ginseng samples were steamed at 100 degrees C. Overall, the use of immersion in fermented tea liquid in conjunction with steam treatment at 100 degrees C could enhance bioactive components and functionality of Korean ginseng product.

关键词： dextran esters   formamidine   gene delivery   polysaccharides   toxicity   transfection  

摘要： Dextran-formamidine esters (dextran-N-[(dimethylamino)methylene]-beta-alanine ester) with different degrees of substitution (0.45-0.92) are synthesized in an one-pot reaction. Dextran (Mw 60 000 g mol(-1)) is allowed to react with unprotected beta-alanine and iminium chloride and investigated regarding the potential as gene delivery system for the transfer of plasmid DNA. With degrees of substitution >= 0.63 improved DNA binding with formation of enzymatically stable complexes of about 130-160 nm with negative surface charges are obtained. These physicochemical characteristics correlated with increasing transfection rates in CHO-K1 cells determined by a luciferase reporter gene assay in dependency of the number of formamidine residues, N/P ratios and amount of DNA. The role of the number of formamidine groups is also highlighted by in vitro cyto- and hemotoxicity tests under the chosen conditions. These results indicate that dextran-formamidine esters are a very promising material for the safe and efficient gene delivery.

关键词： Starch  

摘要： This study aimed to obtain gluten-free pregelatinized composite flours. A central composite rotational design was employed to study the impact of variation of the amount of whole-grain sorghum flour, the conditioning moisture in composite flour, and the temperature in the third zone of the extruder on the flour properties. Conditioning moisture was the parameter that most influenced peak viscosity, trough, final viscosity, and setback of flours. Pregelatinized composite flours with similar pasting properties to cross-linked chemically modified sorghum starches were obtained. While the sorghum flour presented 83.6 degrees C for pasting temperature, 489 cP for peak viscosity, and 1,329 cP for setback, the pregelatinized composite flours presented values between 69-74.4 degrees C, 129-257 cP, and 108-311 cP, respectively. The variation of the process and formulation parameters resulted in the production of flours with well-differentiated pasting properties that would meet specific technological features for application in various foodstuffs, and some optimizations for food applications were shown. Practical applications Broadly driven by consumers who voluntarily avoid or limit gluten in their diets, the demand for gluten-free (GF) products continues strong in the foodservice and retail sectors. Besides, GF has become an expectation for consumers seeking "clean label" products. However, the formulation and the manufacture of baked goods without gluten results in considerable technological problems for both cereal technologists and bakers. Limited research has been performed on the heat treatment of whole-grain sorghum flour. This study provides essential information about the technological characteristics of sorghum-based pregelatinized flours, especially related to their pasting properties. The results show that using these flours will be a good alternative for replacing cross-linked chemically modified sorghum starches. Besides, these flours are valuable to increase

关键词： Strawberry   Gariguette   Polyphenols   Volatiles   Vitamin C  

摘要： In this study, quality parameters (color, soluble solids content, titratable acidity), levels of sugars, organic acids, vitamin C, polyphenols and volatiles were determined during two successive years in Gariguette strawberries harvested at two stages of maturity (turning stage and fully ripe). Fruits were analyzed at harvest and after 2 days of storage at 10 degrees C. The descriptive sensory analyses of the samples were also performed by a trained panel. Whether at harvest or after storage, no significant difference was observed for sugars between samples, but strawberries harvested fully ripe had lower organic acids and higher levels of volatiles. Consistent with these results, strawberries harvested fully ripe were significantly noted sweeter and more aromatic than those harvested 75% red. No significant difference was observed for total vitamin C between samples, but strawberries harvested fully ripe were overall richer in polyphenols, particularly in hydroxycinnamic acids. This suggests strawberries harvested fully ripe could potentially have a greater impact on health.

关键词： Algal bloom   Eutrophication   Phytoplankton   Diversity indices   Water quality parameters  

摘要： Algal bloom of eutrophic freshwaters is important from different aspects of sustainable developmental perspectives. Apart from the identification of the algal species which multiply fast in response to eutrophication, phytoplankton studies concerning water quality parameters of eutrophic waters help environment inventory of such fast-growing algal species. The knowledge of specific environment requirements of fast-growing algae is highly significant in the control of toxic algal blooming and industrial utilization of non-toxic species in phycoremediation or as new bioresources for fuel, food or feeds. In this context, seasonal dynamics of the phytoplankton community in seven different kinds of eutrophic waters from 66 representative locations of Kerala, South India, was measured in two seasons. Altogether, 297 algal species belonging to 8 phyla, 11 classes and 26 orders were observed in the waters. Ecology and diversity of algal communities concerning physicochemical water quality parameters were compared, which enabled assessment of the ecological amplitude of several specific dominant species common to eutrophic waters in Kerala. The crucial roles of dissolved oxygen (p < 0.05), total Kjeldahl nitrogen (p < 0.01), and ammoniacal nitrogen (p < 0.05) in causing algal blooms are assessed using correlation analysis. The principal component analysis extracted the entire water quality parameters into five groups of components acting towards the cause of algal blooms. Overall, the investigation has generated relevant new information of several hitherto uninvestigated fast-growing non-toxic algal species such asKirchneriella lunaris,Ankistrodesmus falcatus,Radiococcus nimbatus,Coelastrum microporumandScenedesmus dimorphus, which are industrially useful and can contribute to ecotechnological innovations essential for sustainable development.