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排序方式: 共有756条查询结果,搜索用时 15 毫秒
731.
Yurong?GaoEmail author Dapeng?Li Shan?Liu Yudi?Liu 《European Food Research and Technology》2012,234(1):45-51
The probiotic properties of Lactobacillus sake C2 isolated from traditional Chinese fermentation cabbage were evaluated. L.
sake C2 displayed good tolerance to the gastrointestinal environments including low pH, presence of bile salts, pepsin, and pancreatin.
L. sake C2 not only could produce the bacteriocin with a broad inhibitory spectrum, but also secrete a large amount of lactic acid
(11.26 mg/mL) and certain amount of H2O2 (3.14 mg/mL). L. sake C2 displayed a high adhesion rate of 15.2 ± 1.2% to Caco-2 cells. Moreover, viable cells of L. sake C2 have fairly strong ability to remove cholesterol (53.2 ± 1.4%). These results indicated that L. sake C2 has a potential as probiotic. Moreover, this study suggested that besides lactic acid bacteria originating from human,
those isolated from fermented foods have potential to be used as probiotic and may be exploited in food industry and probiotic
preparations. 相似文献
732.
利用NiOx薄膜具有优良的电致变色性能,制备了透过率可实时调整的PDP屏滤光膜以提高PDP屏的出光效率,在不同环境照度下获得更好的图像质量。采用扫描电镜(SEM)、X射线衍射仪(XRD)、分光光度计研究了采用磁控溅射法制备的NiOx薄膜中镍的含量对薄膜光电特性的影响。分析测试结果表明:溅射时随着氧分压的提高,氧化镍薄膜的镍含量明显降低;NiOx薄膜中镍原子含量为45%左右时,NiOx薄膜对可见光透过率的调节能力最强,其最高透过率与最低透过率差值达70%。 相似文献
733.
Ponce GM Fajardo MA Zeni SN Luz de Portela M 《Archivos latinoamericanos de nutrición》2006,56(3):237-243
Healthy premenopausal women (Pre n=28) and posmenopausal (Pos n=22), living in Comodoro Rivadavia (Argentina), with normal femoral neck and lumbar spine bone mineral density (BMD) were studied. Usual daily calcium intake (CaI) and protein intake (PrI) were calculated according to an special questionaire and the National Food Composition Tables. Fasting blood samples and 24 h urine were collected. Laboratory measurements were: in urine (U): calcium (Ca), creatinine (Crea) and deoxypiridinoline (Dpyr); in serum: Bone Alkaline Phosphatase (BAPh). The results presented the following media +/- SD (minimum - maximum) in Pre and Pos, respectively: CaI (mg/d): 694 +/- 411 (190 - 2,117); 918 +/- 304 (471 - 1740) (p < 0.01); PrI (g/d): 64.6 +/- 25.4 (33.5 - 136); 63.7 +/- 17.6 (41.5 - 95.2); daily UCa (mg/d): 123 +/- 85 (20 +/- 369); 114 +/- 66 (17 - 252); Ca/crea (mg/mg): 0.124 +/- 0.086 (0.014 - 0.372); 0.131 +/- 0.077 (0.020 - 0.338); Dpyr/crea (nM/mM): 5.5 +/- 1.5 (3.4 - 10.3); 7.1 +/- 2.3 (3.9 - 14.5) (p < 0.01); BAPh (UI/l): 58 +/- 12 (28 - 94); 70 +/- 20 (32 - 99) (p < 0.01). CaI was lower than the Adequate Dietary calcium intake in 86% and 82% of the Pre and Pos women, respectively. There was no correlation between CaI, PrI and the biochemical indicators. Conclusions: in these healthy women, without bone mass loss and with wide range of CaI, although usually low, markers of bone turnover, would be a balance between the increase of bone formation and resorption. 相似文献
734.
Génesis Karendash González‐Quijano Lidia Dorantes‐Alvarez Humberto Hernández‐Sánchez María Eugenia Jaramillo‐Flores María de Jesús Perea‐Flores Arturo Vera‐Ponce de León César Hernández‐Rodríguez 《Journal of food science》2014,79(8):M1545-M1553
The microbiota associated with spontaneous fermentation of vegetables in a saline substrate may represent an important group of bacteria in the food industry. In this work, the lactic acid bacteria (LAB) Weissella cibaria, Lactobacillus plantarum, Lactobacillus paraplantarum, and Leuconostoc citreum were identified by partial 16S rRNA gene sequence analysis. In addition, entophytic bacteria such as Pantoea eucalypti, Pantoea anthophila, Enterobacter cowanii, and Enterobacter asburiae were detected, but they were irrelevant for the fermentation process and were inhibited after 12 h of fermentation when the pH decreased from 6.5 to 4.9. Moreover, 2 species of yeast were isolated and identified as Hanseniaspora pseudoguilliermondii and Kodamaea ohmeri by their partial 26S rRNA gene sequence. The growth of LAB was evaluated at different sodium chloride contents. L. citreum was the most halotolerant species followed by L. plantarum and W. cibaria with a concentration index to obtain a 50% population reduction (IC50) of 7.2%, 6.6%, and 5.2%, respectively. Furthermore, the growth of LAB and Escherichia coli O157:H7 was evaluated in the presence of the main phenylpropanoids from chilli peppers such as p‐coumaric and ferulic acid. It was determined that LAB can grow in both acids at 4 mM, unlike E. coli O157:H7, whose growth is inhibited in the presence of these acids. 相似文献
735.
736.
以TLM钛合金为阳极氧化的基片,通过改变阳极氧化电压、钛合金相结构,找到制备纳米多孔阵列的参数,通过条件试验发现,在恒电压小于30 V时,通过时效处理的TLM钛合金表面可以制备得到TiO2纳米多孔结构薄膜 相似文献
737.
Hargreaves M Parappukkaran S Morawska L Hitchins J He C Gilbert D 《The Science of the total environment》2003,312(1-3):89-101
Indoor air contains a complex mixture of bioaerosols such as fungi, bacteria and allergens, as well as non-biological particles including products from various combustion processes. To date little work has been done to investigate the interactions and associations between particles of biological and non-biological origin, however, any occurring interactions could affect pollutant behaviour in the air and ultimately the effect they have on health. The aim of this work was to examine associations between the concentration levels of airborne particles and fungi measured in 14 residential suburban houses in Brisbane. The most frequently isolated fungal genus was Cladosporium, Curvularia, Alternaria, Fusarium and Penicillium. The average outdoor and indoor (living room) concentrations of fungal colony forming units were 1133+/-759 and 810+/-389, respectively. Average outdoor and indoor (normal ventilation) concentrations of submicrometre and supermicrometre particles were 23.8 x 10(3) and 21.7 x 10(3) (particles/cm(3)), 1.78 and 1.74 (particles/cm(3)), respectively. The study showed that no statistically significant associations between the fungal spore and submicrometre particle concentrations or PM(2.5) were present, while a weak but statistically significant relationship was found between fungal and supermicrometre particle concentrations (for the outdoors R(2)=0.4, P=0.03 and for a living room R(2)=0.3, P=0.04). A similarity in behaviour between the submicrometre particle and fungal spore concentrations was that the fungal spore concentrations were related directly to the distance from the source (a nearby park), in a very similar way in which the submicrometre particles originating from vehicle emissions from a road, were dependent on the distance to the road. In the immediate proximity to the park, fungal concentrations rose up to approximately 3100 CFU/m(3), whereas for houses more than 150 m away from the park the concentrations of fungi were below 1000 CFU/m(3). Recommendations have been provided as the future study designs to gain a deeper insight into the relationships between biological and non-biological particles. 相似文献
738.
Nicoleta Bogatu Lidia Benea Elena Roxana Axente Jean Pierre Celis 《International journal of molecular sciences》2022,23(11)
This paper presents novel results on the effects of the dispersion of titanium carbide nanoparticles (50 nm mean diameter) into a nickel-plating electrolyte on the corrosion behavior of the nanocomposite layers obtained. The Ni/nano-TiC layers are compared with pure nickel layers obtained at the same electrodeposition parameters with 60 mA·cm−2 current density and 10 min deposition time. The comparative corrosion performances are investigated using a three-electrode electrochemical cell in a solution (mixed boric acid with lithium hydroxide), which simulates the primary water circuit of pressurized water reactors (PWRs). Open circuit potential measurement and electrochemical impedance spectroscopy were employed as the electrochemical methods, using an electrochemical workstation connected to an electrochemical cell, as well as a PC with software to drive the experimental work. The results clearly revealed enhanced corrosion properties for the Ni/nano-TiC hybrid layers as compared to the pure Ni layers. The significantly improved corrosion behavior can be attributed to the TiC nanoparticles embedded into the Ni matrix, which have the effect of insulating centers at the composite layer/corrosive solution interface. 相似文献
739.
Tatiana N. Sharapova Olga K. Ivanova Elena A. Romanova Lidia P. Sashchenko Denis V. Yashin 《International journal of molecular sciences》2022,23(10)
An investigation of innate immunity receptors sheds light on the mechanisms of inflammation and associated immune reactions. One of the key immune regulators is the TREM-1 receptor, which is involved in both inflammation and antitumor immune response. In this article, we have obtained a new ligand for the TREM-1 receptor. The peptide, named N3, is a part of the innate immune protein PGLYRP1/Tag7. It is responsible for activating the TREM-1 signaling pathway. Here, we have demonstrated that the N3 peptide acts like other TREM-1 receptor ligands: its binding results in a mild inflammation response and appearance of cytotoxic lymphocytes. We have shown that cytotoxic populations of lymphocytes in N3 peptide-treated PBMCs are similar to those treated with Tag7 or Hsp70. We also determined the part of the N3 peptide responsible for binding to TREM-1. The resulting peptide (N9) consists of nine amino acids and can be considered as a potential peptide that blocks TREM-1 signaling. 相似文献
740.