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511.
Antioxidant and antiinflammatory properties of germinated and hydrolysed Brazilian soybean flours 总被引:1,自引:0,他引:1
The effect of germination in combination with Alcalase hydrolysis of Brazilian soybean cultivar BRS 133 on the production of soybean flours with bioactive peptides as modulators of oxidative stress and markers of inflammation was monitored. The electrophoretic profile showed a weak protein breakdown during germination. However, a strong breakdown of the proteins can be observed after the first hour of hydrolysis with Alcalase. MALDI-TOF-MS analysis of the protein extracts showed differences in the intensity and profile of peptide mass fingerprint due to germination and hydrolysis. Germinated flour showed higher soluble protein concentration and antioxidant capacity. All soybean protein extracts and protein hydrolysates produced (G0, G18 and G72) showed a significant (p < 0.05) inhibition on inflammatory markers such as nitric oxide (20.5–69.3%), iNOS (22.8–93.6%), PGE2 (64.0–88.3%), COX-2 (36.2–76.7%), and TNF-α (93.9–99.5%) in LPS-induced RAW 264.7 macrophages. However, protein extracts of flours with 18 h of germination were more potent in inhibiting pro-inflammatory responses when compared to 72 h. It can be concluded that a combination of 72 h of soybean BRS 133 germination and 1 h Alcalase hydrolysis resulted in the formation of bioactive compounds with more potent antioxidant activity, and improvement in the reduction of some of the markers of inflammation. 相似文献
512.
Pozuelo MJ Agis-Torres A Hervert-Hernández D Elvira López-Oliva M Muñoz-Martínez E Rotger R Goñi I 《Journal of food science》2012,77(2):H59-H62
The digesta is a highly active biological system where epithelial cells, microbiota, nondigestible dietary components, and a large number of metabolic products interact. The gut microbiota can be modulated by both endogenous and exogenous substrates. Undigested dietary residues are substrates for colonic microbiota and may influence gut microbial ecology. The objective of this work was to study the capacity of grape antioxidant dietary fiber (GADF), which is rich in polyphenols, to modify the bacterial profile in the cecum of rats. Male adult Wistar rats were fed for 4 wk with diets containing either cellulose or GADF as dietary fiber. The effect of GADF on bacterial growth was evaluated in vitro and on the cecal microbiota of rats using quantitative real time polymerase chain reaction (RT-PCR). The results showed that GADF intake stimulates proliferation of Lactobacillus and slightly affects the composition of Bifidobacterium species. GADF was also found to have a stimulative effect on Lactobacillus reuteri and Lactobacillus acidophilus in vitro. These findings suggest that the consumption of a diet rich in plant foods with high dietary fiber and polyphenol content may enhance the gastrointestinal health of the host through microbiota modulation. PRACTICAL APPLICATION: Grape antioxidant fiber combines nutritional and physiological properties of dietary fiber and natural antioxidants from grapes. Grape antioxidant fiber could be used as an ingredient for functional foods and as a dietary supplement to increase the intake of dietary fiber and bioactive compounds. 相似文献
513.
E Hierro M Ganan E Barroso M Fernández 《International journal of food microbiology》2012,158(1):42-48
The efficacy of pulsed light to improve the safety of carpaccio has been investigated. Beef and tuna slices were superficially inoculated with approximately 3logcfu/cm(2) of Listeria monocytogenes, Escherichia coli, Salmonella Typhimurium and Vibrio parahaemolyticus. Fluences of 0.7, 2.1, 4.2, 8.4 and 11.9J/cm(2) were assayed. Colour, sensory and shelf-life studies were carried out. Treatments at 8.4 and 11.9J/cm(2) inactivated the selected pathogens approximately by 1logcfu/cm(2), although they modified the colour parameters and had a negative effect on the sensory quality of the product. The raw attributes were not affected by fluences of 2.1 and 4.2J/cm(2) immediately after the treatment, although changes were observed during storage. The inactivation obtained with these fluences was lower than 1logcfu/cm(2), which may not be negligible in case of cross-contamination at a food plant or at a food service facility. Pulsed light showed a greater impact on the sensory quality of tuna carpaccio compared to beef. None of the fluences assayed extended the shelf-life of either product. 相似文献
514.
Profilins are pan-allergen proteins present in various plant foods and pollens. The objective was to develop a method for purification and characterisation of profilin from soy protein isolate. Furthermore, profilin was quantified in soy products and the effect of processing evaluated. Profilin was purified using poly-l-proline affinity chromatography, dialysis and ultrafiltration, and its quantification was implemented by indirect ELISA. Profilin in soymilks ranged from 4.37 ± 0.14 to 7.24 ± 0.30 mg/g protein, while in fermented products profilin ranged from 1.67 ± 0.02 to 5.47 ± 0.02 mg/g protein. Pasteurisation of soymilk was an ineffective method to completely eliminate profilin. Food matrix influenced thermal stability; at 100 °C, β-sheet and random coil structures were altered, while the α-helices remained intact. Induced fermentation of soybean meal by Bifidobacterium lactic, Lactobacillus plantarum and Saccharomyces cerevisiae resulted in 68.3% to 72.7% reduction of soy profilin. Heat treatment, fermentation and hydrolysis effectively reduced soy profilin. 相似文献
515.
Luz Maria Paucar-Menacho Jaime Amaya-Farfán Mark A. Berhow José Marcos Gontijo Mandarino Elvira Gonzalez de Mejia Yoon Kil Chang 《Food chemistry》2010
Soybean is a major source of protein and other nutrients and non-nutrient bioactives for human health. The objective was to compare the bioactive compounds of a low-protein (BRS 133) soybean in comparison to a high-protein (BRS 258) soybean cultivar. The high-protein soybean contained 17% lower carbohydrates and a lower chemical score (63) in relation to the low-protein soybean, which had a higher chemical score (76), associated with the higher methionine content (1.2%). Cultivar BRS 258 had more calcium (15.5%), phosphorus (30.1%), iron (18.7%), copper (9.0%) and zinc (11.5%), and a higher concentrations of lunasin, BBI and lectin (20.3%, 19.0% and 27.1%, respectively) than the low-protein cultivar. BRS 133 had 75.4% higher concentration of total isoflavones (5.1% of total aglycones) and 31.0% total saponins, as compared to BRS 258. It was concluded that the low-protein soybean cultivar contained higher isoflavones and saponins, but lower levels of minerals and bioactive peptides, such as lunasin. 相似文献
516.
Preparation and Characterization of Plasma-Derived Fibrin Hydrogels Modified by Alginate di-Aldehyde
Raúl Sanz-Horta Ana Matesanz Jos Luis Jorcano Diego Velasco Pablo Acedo Alberto Gallardo Helmut Reinecke Carlos Elvira 《International journal of molecular sciences》2022,23(8)
Fibrin hydrogels are one of the most popular scaffolds used in tissue engineering due to their excellent biological properties. Special attention should be paid to the use of human plasma-derived fibrin hydrogels as a 3D scaffold in the production of autologous skin grafts, skeletal muscle regeneration and bone tissue repair. However, mechanical weakness and rapid degradation, which causes plasma-derived fibrin matrices to shrink significantly, prompted us to improve their stability. In our study, plasma-derived fibrin was chemically bonded to oxidized alginate (alginate di-aldehyde, ADA) at 10%, 20%, 50% and 80% oxidation, by Schiff base formation, to produce natural hydrogels for tissue engineering applications. First, gelling time studies showed that the degree of ADA oxidation inhibits fibrin polymerization, which we associate with fiber increment and decreased fiber density; moreover, the storage modulus increased when increasing the final volume of CaCl2 (1% w/v) from 80 µL to 200 µL per milliliter of hydrogel. The contraction was similar in matrices with and without human primary fibroblasts (hFBs). In addition, proliferation studies with encapsulated hFBs showed an increment in cell viability in hydrogels with ADA at 10% oxidation at days 1 and 3 with 80 µL of CaCl2; by increasing this compound (CaCl2), the proliferation does not significantly increase until day 7. In the presence of 10% alginate oxidation, the proliferation results are similar to the control, in contrast to the sample with 20% oxidation whose proliferation decreases. Finally, the viability studies showed that the hFB morphology was maintained regardless of the degree of oxidation used; however, the quantity of CaCl2 influences the spread of the hFBs. 相似文献
517.
Ariel Cavazos Elvira Gonzalez de Mejia 《Comprehensive Reviews in Food Science and Food Safety》2013,12(4):364-380
Cereal grains, such as wheat, barley, rice, rye, oat, millet, sorghum, and corn, have been staples in human diets since ancient times. At present, there is a significant body of scientific evidence showing the health benefits of consuming whole grains in chronic disease prevention, particularly in regards to diabetes, cardiovascular disease, and cancer. The objective was to determine bioactive peptides in cereal grains that may prevent cardiovascular disease, cancer, inflammation, and diabetes. Bioactive peptides that may be obtained from cereal grains, particularly wheat, oat, barley, and rice, were identified. Bioactive peptides that play a role in chronic disease prevention have been found primarily in legumes and dairy products; although research connecting cereal grains with potential bioactive peptide activity is limited. In this review, 4 cereal grains, wheat, oat, barley, and rice, were evaluated for bioactive peptide potential using the BIOPEP database. In addition, research information was compiled for each grain regarding evidence about the effect of their proteins in prevention of chronic diseases. All 4 grains showed high occurrence frequencies of angiotensin‐converting enzyme‐inhibitor peptides (A = 0.239 to 0.511), as well as of dipeptidyl peptidase‐inhibitor and antithrombotic, antioxidant, hypotensive, and opioid activity. Wheat and rice proteins had anticancer sequences present. Wheat and barley showed the greatest diversity and abundance of potential biological activity among the cereal proteins. Further research needs to be conducted to learn how these biologically active peptide sequences are released from cereal grains. This study supports the notion that cereal grains are a nutritious part of a healthy diet by preventing chronic diseases. 相似文献
518.
Enrique García-Recio Víctor J. Costela-Ruiz Lucía Melguizo-Rodriguez Javier Ramos-Torrecillas Olga García-Martínez Concepcin Ruiz Elvira de Luna-Bertos 《International journal of molecular sciences》2022,23(10)
(1) Background: Bisphenol A (BPA) is an endocrine disruptor that is widely present in the environment and exerts adverse effects on various body tissues. The objective of this study was to determine its repercussions on bone tissue by examining its impact on selected functional parameters of human osteoblasts. (2) Methods: Three human osteoblast lines were treated with BPA at doses of 10−5, 10−6, or 10−7 M. At 24 h post-treatment, a dose-dependent inhibition of cell growth, alkaline phosphatase activity, and mineralization was observed. (4) Results: The expression of CD54 and CD80 antigens was increased at doses of 10−5 and 10−6 M, while the phagocytic capacity and the expression of osteogenic genes (ALP, COL-1, OSC, RUNX2, OSX, BMP-2, and BMP-7) were significantly and dose-dependently reduced in the presence of BPA. (5) Conclusions: According to these findings, BPA exerts adverse effects on osteoblasts by altering their differentiation/maturation and their proliferative and functional capacity, potentially affecting bone health. Given the widespread exposure to this contaminant, further human studies are warranted to determine the long-term risk to bone health posed by BPA. 相似文献
519.
Solution Combustion Synthesis: Low‐Temperature Processing for p‐Type Cu:NiO Thin Films for Transparent Electronics
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Ao Liu Huihui Zhu Zidong Guo You Meng Guoxia Liu Elvira Fortunato Rodrigo Martins Fukai Shan 《Advanced materials (Deerfield Beach, Fla.)》2017,29(34)
Low‐temperature solution processing opens a new window for the fabrication of oxide semiconductors due to its simple, low cost, and large‐area uniformity. Herein, by using solution combustion synthesis (SCS), p‐type Cu‐doped NiO (Cu:NiO) thin films are fabricated at a temperature lower than 150 °C. The light doping of Cu substitutes the Ni site and disperses the valence band of the NiO matrix, leading to an enhanced p‐type conductivity. Their integration into thin‐film transistors (TFTs) demonstrates typical p‐type semiconducting behavior. The optimized Cu5%NiO TFT exhibits outstanding electrical performance with a hole mobility of 1.5 cm2 V?1 s?1, a large on/off current ratio of ≈104, and clear switching characteristics under dynamic measurements. The employment of a high‐k ZrO2 gate dielectric enables a low operating voltage (≤2 V) of the TFTs, which is critical for portable and battery‐driven devices. The construction of a light‐emitting‐diode driving circuit demonstrates the high current control capability of the resultant TFTs. The achievement of the low‐temperature‐processed Cu:NiO thin films via SCS not only provides a feasible approach for low‐cost flexible p‐type oxide electronics but also represents a significant step toward the development of complementary metal–oxide semiconductor circuits. 相似文献
520.
Binary alloy Cu–Ni nanoparticles were synthesized by sonoelectrochemical technique from aqueous bath in presence of Na-citrate as complexing agent, to allow co-deposition of Cu and Ni. Alloy Pulsed Electro-Deposition (PED) was carried out to study nucleation kinetic and the effects of pH and surfactant on the final product physical and chemical properties, with the aim to determine optimized parameters for subsequent sonoelectrosyntheses of nanoparticles. Role of pH and Na-citrate in the synthesis process was investigated and it was found that i) pH is the main parameter affecting the stability of synthesis solutions, ii) Na-citrate content influences the sonoelectrochemical process efficiency but at the same time iii) the complexing agent is necessary to obtain Cu and Ni co-deposition; iv) produced nanoparticles are made of CuNi alloy with a fcc crystalline structure and v) pH is weakly responsible of increase in mean grain size of produced nanoparticles. 相似文献