摘要：
This study is aimed to explore the optimal conditions of cell disruption in the extraction algae oil process, using alkaline protease to disrupt cell of Schizochytrium sp. to extract oil in this paper. The effects of enzymatic lysis temperature, enzymatic lysis time, enzyme dosage and pH value on oil yield and DHA yield were studied. Through the combination of single factor test and response surface design, the optimal cell disruption conditions were screened out. The fatty acid composition of algal oil was analyzed by gas chromatography-massspectrometry (GC-MS). The results showed that when the conditions were: enzymatic lysis temperature 55 degrees C, enzymatic lysis time 9 h, enzyme dosage 3% of biomass and pH 8,oil yield and DHA yield reached the highest 14.52 g/L and 7.12 g/L, respectively. When the strains were cultured in 50 L fermentor, oil yield reached 26.27 g/L and DHA yield reached 12.89 g/L. They were 1.81 times higher than that in shake-flask cultivation. The optimization experiment provides the basis for the industrial production of Schizochytrium sp.
摘要：
Nanoencapsulation of alpha-tocopherol (alpha-TOC) by blending sodium oleate (NaOl) and rebaudioside A (RebA) was successfully prepared by self-assembly method under mild conditions. The optimized nanoemulsion showed the loading capacity of alpha-TOC was 30 wt% of sodium oleate. FTIR analysis suggested that hydrogen bonds and hydrophobic interactions were the major forces in alpha-TOC-NaOl/RebA complexes that were spherical and possessed well-distinguishable core-shell structures. The freeze-dried alpha-TOC-NaOl/RebA complexes had great stability under ambient conditions. The release profile of alpha-TOC showed a first-order kinetics reaching around 67.9% after 90 h at 25 degrees C. Nanoencapsulation improved dispersibility and greatly increased the antioxidant activity of alpha-TOC. Therefore, the stable alpha-TOC-NaOl/RebA core-shell complexes prepared from "generally recognized as safe" (GRAS) ingredients have great potential to supplement alpha-TOC in food and cosmetic products.
摘要：
Interfacial adsorption kinetics and stabilizing emulsion behavior of lysozyme/xanthan gum nanoparticles (Ly/XG NPs) by variation of particle size and energy input. The interfacial rheology indicated that interfacial adsorption behavior of Ly/XG NPs displayed in a particle size manner. Increasing the particle size of Ly/XG NPs hindered its initial diffusion onto the interface. Smaller size was helpful for its fast diffusion to the interface. K-p (rate constant of penetration) and K-R (rate constant of penetration) of Ly/XG NPs were both affected by particle size. The K-p for adsorbed Ly/XG NPs increased as the particle sizes increased. K-R was considerably higher than K-p, indicating the structural rearrangement of adsorbed Ly/XG NPs played an important part in interfacial film formation. The morphology of Pickering emulsion indicated its drop sizes were determined by the oil/aqueous volume fraction and prepared style. The higher energy input the size become smaller. Based on interfacial adsorption kinetics and microstructure of Pickering emulsions, the stabilization behavior was related to particle-particle associations and conformational changes of Ly/XG NPs. This work confirmed Ly/XG NPs could form Pickering emulsion by selecting different particle size and emulsification process, and offer promising prospects in stabilizing emulsion with the demands of surfactant-free. (C) 2018 Elsevier B.V. All rights reserved.
摘要：
Litchi polysaccharide (IP) was extracted from litchi pulp. Its chemical composition, microstructure, zeta potential, flow and viscoelastic behavior were investigated. LP contained uronic acid (41.18%), neutral sugar (4223%), and protein (2.72%). The monosaccharide composition was mostly arabinose, galactose, and a small amount of mannose, rhamnose and glucose. Scanning electron microscopy (SEM) showed IP was porous network structure. LP concentration had no effect on its zeta potential value while salts reduced them. LP showed shear-thinning behavior during the tested shear rate range. The power-law model was used to evaluate the flow behavior of LP; both its flow behavior index and consistency index changed with different concentrations. The viscosity of LP increased under acidic conditions (pH 2-4), but was stable with heat treatment. The LP dispersion displayed as a liquid viscoelastic behavior in 1% and 2% concentrations and behaved as an elastic gel at 3% concentration as well as the addition of NaCl and CaCl2. (C) 2018 Published by Elsevier B.V.
通讯机构：
[Cai, J; He, JR] W;[Xiong, Xin-Gao] H;Wuhan Polytech Univ, Sch Food Sci & Engn, Wuhan 430023, Hubei, Peoples R China.;Huazhong Univ Sci & Technol, Dept Otorhinolaryngol Head & Neck Surgery, Union Hosp, Tongji Med Coll, Wuhan 430022, Hubei, Peoples R China.;Wuhan Polytech Univ, Key Lab Deep Proc Major Grain & Oil, Minist Educ, Wuhan, Hubei, Peoples R China.
关键词：
Starch;Porous starch;Microencapsulation
摘要：
In this study, starch with porous structures derived from purple sweet potato was prepared and used as a food grade polymer for the microencapsulation of olive oil. The optimal reaction conditions for preparing porous starch were determined to improve its adsorption capacity as effective microcapsule-wall materials. Olive oil was then impregnated in microspheres, and loading ratio was optimized by investigating the restrictive factors, including the mass ratio of olive oil to porous starch, as well as the embedding temperature and time. The presence of olive oil in the starch matrix was confirmed by SEM, FTIR, and TGA. Results demonstrated that the porous starch-based microencapsulation exhibit a stable olive oil loading ratio and a significant improvement in oxidative stability compared with free olive oil. The newly-proposed process used in this work was easy to scale up for developing a new and attractive method for oil protection in the food industry. (C) 2018 Elsevier B.V. All rights reserved.
摘要：
Exposure to PM2.5 has become one of the most important factors affecting public health in the world. Both clinical and research studies have suggested that PM2.5 inhalation is associated with impaired lung function. In this study, material characterization identified the existence of nanoscale particulate matter (NPM) in airborne PM2.5 samples. When coming into contact with protein-rich fluids, the NPM becomes covered by a protein layer that forms a "protein corona". Based on a 3D organotypic cell culture, the protein corona was shown to mitigate NPM cytotoxicity and further stimulate the proliferation of human lung fibroblasts (HLFs). ROS-activated alpha-smooth muscle actin (alpha-SMA) is considered to be one of the proliferation pathways. In this research, 3D cell cultures exhibited more tissue-like properties compared with the growth in 2D models. Animal models have been widely used in toxicological research. However, species differences make it impossible to directly translate discoveries from animals to humans. In this research, the 3D HLF model could partly simulate the biological responses of NPM-protein corona-induced aberrant HLF proliferation in the human lung. Our 3D cellular results provide auxiliary support for an animal model in research on PM2.5-induced impaired lung function, particularly in lung fibrosis.
关键词：
sunflower protein hydrolysates;angiotensin-I-converting enzyme inhibitory peptides;liposome;response surface methodology
摘要：
'Obesity Facts' publishes articles covering all aspects of obesity, in particular epidemiology, etiology and pathogenesis, treatment, and the prevention of adiposity. As obesity is related to many disease processes, the journal is also dedicated to all topics pertaining to comorbidity and covers psychological and sociocultural aspects as well as influences of nutrition and exercise on body weight. The editors carefully select papers to present only the most recent findings in clinical practice and research. All professionals concerned with obesity issues will find this journal a most valuable update to keep them abreast of the latest scientific developments.Special sections comprising a variety of subspecialties reinforce the journal's value as an exhaustive record of recent progress for all internists, gastroenterologists, endocrinologists, pediatricians, dieticians, nutritionists, bariatric surgeons, psychologists and psychiatrists, occupational health practitioners, sports medicine specialists, ecotrophologists, sociologists, and biologists as well as prevention and public health researchers. In addition, 'Obesity Facts' serves as an ideal information tool for the members of the pharmaceutical and food industry as well as those active in nutritional research and medicine.
摘要：
Staphylococcal enterotoxins (SEs), also known as superantigens, play a very important role in infections and food poisoning caused by Staphylococcus aureus. Recently, S. argenteus and S. schweitzeri were recognized as novel species closely related to S. aureus. In this study of these three species, it was found that two putative SE genes were located upstream of some vSabeta pathogenicity islands and the deduced amino acid sequences showed <65.3% identity with those of known SEs. The related proteins, designated staphylococcal enterotoxin-like toxin 26 (SEl26) and 27 (SEl27), were identified and characterized among the three species. The mRNAs encoding SEl26 and SEl27 were expressed during all the growth phases. Recombinant SEl26 and SEl27 exhibited superantigenic activity in human peripheral blood mononuclear cells and mouse splenocytes by examining cell proliferation and cytokine production. Interestingly, these two genes were present universally in S. argenteus sequence type 2250 with clinical importance. Meanwhile, SEl27 variants from different species showed differential sensitivity to human peripheral blood mononuclear cells, which corresponded to the primary bacterial species hosts. It was demonstrated from these results that SEl26 and SEl27 were characterized to be two novel SE toxins and some SEs evolved along with the bacteria when the organisms adapted the hosts' immune systems.
摘要：
In this study, pectin was used as coating material to form zein/caseinate/pectin complex nanoparticles through pH adjustment and heating treatment for potential oral delivery applications. The preparation conditions were studied by applying heating treatment at different pHs, either the isoelectric point of zein (pH 6.2) or caseinate (pH 4.6), or consecutively at both pHs. The particulate characteristics, including particle size, polydispersity index, and zeta potential were monitored for complex nanoparticles formed under different preparation conditions. The complex nanoparticles generally exhibited particle size smaller than 200 nm with narrow distribution, spherical shape, and strong negative charge. Fourier transform infrared and fluorescence spectroscopy revealed that hydrophobic interactions and hydrogen bonds were involved in the formation of complex nanoparticles, in addition to electrostatic interactions. Fresh colloidal dispersion and freeze-dried powders varied in their morphology, depending on their preparation conditions. Our results suggested that heating pH and sequence significantly affected the morphology of complex nanoparticles, and pectin coating exerted stabilization effect under simulated gastrointestinal conditions. The present study provides insight into the formation of protein/polysaccharide complex nanoparticles under different preparation conditions. (C) 2017 Elsevier B.V. All rights reserved.
摘要：
A sedentary lifestyle and poor diet are risk factors for the progression of non-alcoholic fatty liver disease. However, the pathogenesis of hepatic lipid accumulation is not completely understood. Therefore, the present study explored the effects of dietary supplementation of various ratios of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on a high-fat diet-induced lipid metabolism disorder and the concurrent liver damage. Using high-fat diet-fed C57BL/6 J mice as the animal model, diets of various ratios of DHA/EPA (2:1, 1:1, and 1:2) with an n-6/n-3 ratio of 4:1 were prepared using fish and algae oils enriched in DHA and/or EPA and sunflower seed oils to a small extent instead of the high-fat diet. Significantly decreased hepatic lipid deposition, body weight, serum lipid profile, inflammatory reactions, lipid peroxidation, and expression of adipogenesis-related proteins and inflammatory factors were observed for mice that were on a diet supplemented with DHA/EPA compared to those in the high-fat control group. The DHA/EPA 1:2 group showed lower serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol levels, lower SREBP-1C, FAS, and ACC-1 relative mRNA expression, and higher Fra1 mRNA expression, with higher relative mRNA expression of enzymes such as AMPK, PPARα, and HSL observed in the DHA/EPA 1:1 group. Lower liver TC and TG levels and higher superoxide dismutase levels were found in the DHA/EPA 2:1 group. Nonetheless, no other notable effects were observed on the biomarkers mentioned above in the groups treated with DHA/EPA compared with the DHA group. The results showed that supplementation with a lower DHA/EPA ratio seems to be more effective at alleviating high-fat diet-induced liver damage in mice, and a DHA/EPA ratio of 1:2 mitigated inflammatory risk factors. These effects of n-3 polyunsaturated fatty acids (PUFA) on lipid metabolism may be linked to the upregulation of Fra1 and attenuated activity of c-Jun and c-Fos, thus ultimately reducing the severity of the lipid metabolism disorder and liver damage to some extent.
