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排序方式: 共有825条查询结果,搜索用时 234 毫秒
91.
Salazar Alzate BC Montoya Campuzano OI Sepúlveda Valencia JU 《Archivos latinoamericanos de nutrición》2005,55(4):350-353
The objective of this research was to test the viability of a native isolate of Lactobacillus brevis in two fermented milky drinks: a drink without prebiotic ingredient and another drink with oat flour (0.5%, p/v) as prebiotic ingredient. The viability of L. brevis was tested at 7, 14, and 21 after inoculation. Drink pH and lactic acid concentration was measured as a function of time (2, 7, 14, and 21 days after inoculation). The isolate was viable in both drinks because its counting plates was higher than 10(6) CFU/mL until day 21st. Between the 7th and 14th day, the rate of growth was higher in the drink that included oat flour, however, at the day 21st the colony density was similar in both drinks. 相似文献
92.
We described herein, the construction of an organic phase enzyme electrode (OPEE) via polyphenol oxidase (PPO) entrapment within a hydrophilic polypyrrole film electrogenerated from on a new bispyrrolic derivative (1) containing a long hydrophilic spacer. The so-called “adsorption step procedure” was adopted for the preparation of the organic phase PPO biosensor. The amperometric detection of catechol was carried out in anhydrous chloroform at −0.2 V versus Ag/AgCl. The electroanalytical parameters of the biosensor strongly depend on its configuration and on the hydration state of the enzyme matrix. The best sensitivity obtained for catechol in chloroform was 15.6 mA M−1 cm−2. 相似文献
93.
T Cecilia 《Canadian Metallurgical Quarterly》1977,118(45):2719-2720
94.
Phenolic acids composition and antioxidant activity of canola extracts in cooked beef,chicken and pork 总被引:2,自引:0,他引:2
Crude polyphenol extracts (15 or 100 mg gallic acid equivalents (GAE)/kg meat) from canola meal reduced the formation of 2-thiobarbituric acid-reactive substances (TBARS) in pre-cooked beef (66–92%), pork (43–75%) and chicken (36–70%). The canola extract contained sinapic (99.7%), ferulic (0.28%) and p-hydroxybenzoic acids (0.07%). 相似文献
95.
Cecilia A Svelander Evelina A Tibäck Lilia M Ahrné Maud IBC Langton Ulf SO Svanberg Marie AG Alminger 《Journal of the science of food and agriculture》2010,90(10):1665-1672
BACKGROUND: Human studies have demonstrated that processing of tomato can greatly increase lycopene bioavailability. However, the difference between processing methods is not widely investigated. In the current study different thermal treatments of tomato were evaluated with regard to their impact on in vitro bioaccessibility and retention of lycopene and β‐carotene as well as textural properties. Thermal treatments used were low (60 °C) and high (90 °C) temperature blanching followed by boiling. RESULTS: Lycopene was relatively stable during thermal treatment, whereas β‐carotene was significantly (P < 0.05) reduced by all heat treatments except for low temperature blanching. In vitro bioaccessibility of lycopene was significantly increased from 5.1 ± 0.2 to 9.2 ± 1.8 and 9.7 ± 0.6 mg kg?1 for low and high temperature blanching, respectively. An additional boiling step after blanching did not further improve lycopene bioaccessibility for any treatment, but significantly reduced the consistency of low temperature treated samples. CONCLUSION: Choice and order of processing treatments can have a large impact on both lycopene bioavailability and texture of tomato products. Further investigations are needed, but this study provides one of the first steps towards tomato products tailored to optimise nutritional benefits. Copyright © 2010 Society of Chemical Industry 相似文献
96.
Yiling Lee Yu Zhang Serene Lay Geok Ng Fransiska Cecilia Kartawidjaja John Wang 《Journal of the American Ceramic Society》2009,92(9):1940-1945
Vertically aligned, single crystalline ZnO nanorods with a high packing density and diameter of ∼60 nm have been successfully synthesized via a low-temperature hydrothermal route on glass substrates pre-deposited with a ZnO seeding layer. The seeding layer exhibits an epitaxial effect on the growth and alignment of the ZnO nanorods. This epitaxial effect can arise from two considerations, namely the crystalline orientation and surface roughness of the seeding layer, which can be controlled by the curing temperature. The ZnO seeding layer that was cured at 350°C exhibited a preferred (0002) crystalline orientation of wurtzite hexagonal structure and a low surface roughness. It was demonstrated to promote the vertical growth of ZnO nanorods. The ZnO nanorods grew in an almost linear relationship with hydrothermal time up to 8 h, but thereafter started to dissolve as the reaction time extended beyond 8 h, due to competition from the homogeneous nucleation of ZnO microparticles in the solution. 相似文献
97.
The antioxidant capacities of 11 botanical species used in the tradition of Sardinia as teas beverages or as decoction for medicinal purposes were evaluated using different in vitro methods (BR, TEAC, DPPH and FC). Among the various species, Rubus ulmifolius, resulted the more active with all the used methods. Phytochemical investigation on the extract yields in the isolation of several phenolic compounds namely caffeic acid, ferulic acid, quercetin-3-O-glucuronide, kaempferol-3-O-glucuronide, kaempferol-3-O-(6″-p-coumaroyl)-β-d-glucopyranoside, kaempferol-3-O-(6″-caffeoyl)-β-d-glucopyranoside, chlorogenic acid, 4-caffeoylquinic acid and 5-caffeoylquinic acid. The antioxidant activity of isolated compounds was also evaluated. 相似文献
98.
Guerrero-Torres A. Jiménez-Gómez C. P. Cecilia J. A. García-Sancho C. Franco F. Quirante-Sánchez J. J. Maireles-Torres P. 《Topics in Catalysis》2019,62(5-6):535-550
Topics in Catalysis - Nickel-based catalysts supported on sepiolite catalysts, with a nickel loading between 1 and 10 wt%, have been synthesized by several synthetic strategies... 相似文献
99.
Antonella Gori Cecilia Brunetti Luana Beatriz dos Santos Nascimento Giovanni Marino Lucia Guidi Francesco Ferrini Mauro Centritto Alessio Fini Massimiliano Tattini 《International journal of molecular sciences》2021,22(15)
Carotenoids and phenylpropanoids play a dual role of limiting and countering photooxidative stress. We hypothesize that their “antioxidant” function is prominent in plants exposed to summer drought, when climatic conditions exacerbate the light stress. To test this, we conducted a field study on Phillyrea latifolia, a Mediterranean evergreen shrub, carrying out daily physiological and biochemical analyses in spring and summer. We also investigated the functional role of the major phenylpropanoids in different leaf tissues. Summer leaves underwent the most severe drought stress concomitantly with a reduction in radiation use efficiency upon being exposed to intense photooxidative stress, particularly during the central hours of the day. In parallel, a significant daily variation in both carotenoids and phenylpropanoids was observed. Our data suggest that the morning-to-midday increase in zeaxanthin derived from the hydroxylation of ß-carotene to sustain non-photochemical quenching and limit lipid peroxidation in thylakoid membranes. We observed substantial spring-to-summer and morning-to-midday increases in quercetin and luteolin derivatives, mostly in the leaf mesophyll. These findings highlight their importance as antioxidants, countering the drought-induced photooxidative stress. We concluded that seasonal and daily changes in photosynthetic and non-photosynthetic pigments may allow P. latifolia leaves to avoid irreversible photodamage and to cope successfully with the Mediterranean harsh climate. 相似文献
100.
Cecilia Berlin Lars-Ola Bligrd Maral Babapour Chafi Siw Eriksson 《人机工程学与制造业中的人性因素》2022,32(1):151-170
In any work system design intervention—for example, a physical workplace re-design, a work process change, or an equipment upgrade—it is often emphasized how important it is to involve stakeholders in the process of analysis and design, to gain their perspectives as input to the development, and ensure their future acceptance of the solution. While the users of an artifact or workplace are most often regarded as being the most important stakeholders in a design intervention, in a work-system context there may be additional influential stakeholders who influence and negotiate the design intervention's outcomes, resource allocation, requirements, and implementation. Literature shows that it is uncommon for empirical ergonomics and human factors (EHF) research to apply and report the use of any structured stakeholder identification method at all, leading to ad-hoc selections of whom to consider important. Conversely, other research fields offer a plethora of stakeholder identification and analysis methods, few of which seem to have been adopted in the EHF context. This article presents the development of a structured method for identification, classification, and qualitative analysis of stakeholders in EHF-related work system design intervention. It describes the method's EHF-related theoretical underpinnings, lessons learned from four use cases, and the incremental development of the method that has resulted in the current method procedure and visualization aids. The method, called Change Agent Infrastructure (abbreviated CHAI), has a mainly macroergonomic purpose, set on increasing the understanding of sociotechnical interactions that create the conditions for work system design intervention, and facilitating participative efforts. 相似文献