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991.
So far, data on absorption and metabolism of steryl ferulates from edible sources is scarce. Therefore, the impact of enzyme-aided baking and in vitro digestion was examined in this study. Wheat flours and wheat breads were subjected to a static in vitro digestion model and changes in the contents of steryl ferulates and free sterols (possible hydrolysis products of steryl ferulates) were monitored. Baking degraded steryl ferulates at a similar rate in all types of breads (43–47%) compared to the corresponding flours, while baking induced changes in free sterols showed no clear pattern. In vitro digestion provoked five folds lower content of steryl ferulates in flours than in breads and it also resulted in significant free sterol accumulation. Interestingly, bioaccessibility (0.01–0.25%) was not influenced by the cereal matrix. The four steryl ferulate species, which were detected in wheat, showed similar hydrolysis rates during digestion. As baking had a significant impact on the steryl ferulate content of wheat, we suggest that both raw and processed sources should be considered further in vitro, animal or human trials, when studying the metabolic fate of steryl ferulates. 相似文献
992.
Christoph Brunschwiler Daniel Heine Stefan Kappeler Beatrice Conde-Petit Laura Nyström 《Journal of Cereal Science》2013
Rice bran is a rich source of valuable nutrients and has potential for high-value applications. Endogenous lipases catalyze the hydrolysis of rice bran oil to free fatty acids, which initiates lipid oxidation. The evaluation of the success of rice bran stabilization processes in terms of the degree of lipid oxidation and shelf-life has so far relied on the measurement of free fatty acid content over a storage period of 3–6 months. In the present study, a photometric and a titrimetric pH-stat method for direct lipase activity measurement immediately after debranning were adapted to rice bran. The photometric method was further applied to determine rice bran lipase/esterase inactivation kinetics, which are useful to optimize stabilization treatments in order to prevent overprocessing and retain maximum level of nutrients. Rice bran was heat-treated in a specialized, hermetically sealable reactor at controlled holding times (5–40 min), temperatures (70–145 °C) and moisture contents (10–20%). Temperature dependency of the lipase/esterase inactivation rate could be described by the Arrhenius equation. Empirical findings on the importance of moisture content for effective rice bran stabilization could be quantified. Furthermore, the results demonstrate the great potential of the method to predict the shelf-life of stabilized rice bran without time-consuming storage tests. 相似文献
993.
Martin Komainda Kai Küchenmeister Frank Küchenmeister Laura Breitsameter Nicole Wrage‐Mnnig Manfred Kayser Johannes Isselstein 《Journal of Agronomy and Crop Science》2019,205(5):460-469
Dairy livestock production systems rely on high‐quality forage legumes, which are widely present in grassland swards all over Europe. A future climatic scenario with higher average annual temperatures and lower precipitation is expected to affect grassland productivity in general and the productivity of the most important forage legume species Trifolium repens in particular. One way to cope with such constraints is the adoption of currently underutilized minor legume species with a higher tolerance towards drought stress. Therefore, the present study investigated legume species with lower moisture requirements than T. repens, these are Lotus corniculatus, Medicago falcata, Medicago lupulina and Onobrychis viciifolia in comparison with T. repens. Legumes were grown in containers as monocultures in a roofed open‐sided greenhouse under conditions of optimal water supply or periodic drought stress. Generally, drought stress decreased the biomass production, but species differed in their reaction. Particularly, M. lupulina and L. corniculatus had lower relative biomass losses (?26%) compared to T. repens (?43%, as averaged over drought stress periods). However, in overall biomass production T. repens still was at one level with M. lupulina and L. corniculatus under drought stress. This was related to high stomata control as indicated by the intrinsic water‐use efficiency. We conclude that there are promising future options of forage legumes as alternatives to T. repens. 相似文献
994.
Francesco Gai Laura Gasco Franco Daprà Giovanni B. Palmegiano Benedetto Sicuro 《Journal of the World Aquaculture Society》2012,43(2):218-229
This study was carried out in order to investigate the histological and biochemical responses in the gastrointestinal tract (GIT) of rainbow trout fed a rice protein concentrate (RPC). A stock of 360 juvenile rainbow trout (62.4 ± 0.3 g) were randomly distributed into 12 fiberglass tanks and fed with four experimental diets obtained by including graded levels of RPC (RPC: 0, 20, 35, and 53%) replacing fish meal on dry weight basis. The experimental plan was balanced and monofactorial, with four treatments and three replicates. At the end of the experiment, 15 fish per treatment were killed, and different tissues were sampled for biochemical and histological analyses. The results showed that total alkaline proteases were unaffected by RPC inclusion level. Amylase and lipase activities showed slight differences between the groups for all examined tracts. No histopathological changes were observed in GIT for any of the dietary treatments. Liver samples of fish fed with RPC‐based diets were characterized by a slight decrease in lipid vacuolizations and a decreasing trend in the Ceroid Substances Presence Index. In conclusion, RPC did not show detrimental effects on the intestinal morphology and modification of tissue enzyme activity in rainbow trout. 相似文献
995.
Yamila Eliana Rodriguez Hernn Javier Sacristn María Victoria Laitano Laura Susana Lpez‐Greco Analía V. Fernndez‐Gimenez 《Journal of the World Aquaculture Society》2019,50(5):954-968
This research studied the in vitro compatibility of Cherax quadricarinatus digestive proteases and crude enzyme extracts recovered from fish‐processing waste to evaluate their potential use as feed additives to increase digestion efficiency in decapod crustaceans. The sources of exogenous enzymes were: Pleoticus muelleri (Pm), Artemesia longinaris (Al), and Illex argentinus (Ia). The midgut glands of early (7.2 ± 0.34 g) and advanced juveniles (13.8 ± 1.49 g) of C. quadricarinatus were used for all the assays. The compatibility and synergy between crayfish and exogenous enzymes were evaluated through sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) electrophoresis and the hydrolysis of azocasein and four different meals. SDS–PAGE gels demonstrated that crayfish bands remained active when their enzymes were combined with the enzymes from Pm and Ia. An apparent enzymatic synergism was found when Pm and crayfish proteases were incubated together at pH 6 and 8 with azocasein (p ? 0.05). The ability to hydrolyze the different feed ingredients varied among the enzyme combinations assayed. Our findings suggest that fish waste has potential as a source of proteases, adding value to these processing residues and promoting a zero‐waste industry. Enzymes obtained from Pm and Ia are suitable to be used as food additives for crayfish. The results should be validated through feeding trials. 相似文献
996.
997.
John Gloster Andrew Jones Alison Redington Laura Burgin Jens H. Sørensen Richard Turner Michael Dillon Pam Hullinger Matthew Simpson Poul Astrup Graeme Garner Paul Stewart Réal D’Amours Robert Sellers David Paton 《Veterinary journal (London, England : 1997)》2010,183(3):278-286
Foot-and-mouth disease virus (FMDV) spreads by direct contact between animals, by animal products (milk, meat and semen), by mechanical transfer on people or fomites and by the airborne route, with the relative importance of each mechanism depending on the particular outbreak characteristics. Atmospheric dispersion models have been developed to assess airborne spread of FMDV in a number of countries, including the UK, Denmark, Australia, New Zealand, USA and Canada. These models were compared at a Workshop hosted by the Institute for Animal Health/Met Office in 2008. Each modeller was provided with data relating to the 1967 outbreak of FMD in Hampshire, UK, and asked to predict the spread of FMDV by the airborne route.A number of key issues emerged from the Workshop and subsequent modelling work: (1) in general all models predicted similar directions for livestock at risk, with much of the remaining differences strongly related to differences in the meteorological data used; (2) determination of an accurate sequence of events on the infected premises is highly important, especially if the meteorological conditions vary substantially during the virus emission period; (3) differences in assumptions made about virus release, environmental fate and susceptibility to airborne infection can substantially modify the size and location of the downwind risk area. All of the atmospheric dispersion models compared at the Workshop can be used to assess windborne spread of FMDV and provide scientific advice to those responsible for making control and eradication decisions in the event of an outbreak of disease. 相似文献
998.
Laura D. Barnes Jacqueline W. Pearce Linda M. Berent Derek B. Fox Elizabeth A. Giuliano 《Veterinary ophthalmology》2010,13(4):251-258
A 27 kg, 6‐year‐old, male castrated German shorthaired pointer presented to the University of Missouri, Veterinary Teaching Hospital with the complaint of progressive exophthalmia of 2 years duration optical density (OD). Lack of retropulsion OD was noted on physical examination. Anterior segment examination OU and fundic examination OS did not reveal any abnormalities. Examination of the fundus OD revealed focal scleral indentation of the inferior nasal globe. The indentation changed location with globe movement OD. MRI and CT scan revealed a well‐circumscribed, approximately 2 cm in diameter mass located caudal and ventral to the affected globe that appeared to communicate with the nictitating membrane with absence of any bony involvement. A modified lateral orbitotomy was recommended and performed to remove the orbital mass and nictitating membrane en‐bloc. Histopathology and immunohistochemistry of the mass confirmed a diagnosis of nodular granulomatous episcleritis (NGE). Postoperatively, the dog developed absolute keratoconjunctivitis sicca (KCS). Examples of primary episcleral inflammation in the dog include diffuse episcleritis, NGE, nodular fasciitis, fibrous histiocytoma, proliferative conjunctivitis/keratoconjunctivitis, pseudotumor, and Collie granuloma. The etiology of these episcleral inflammations is presumed to be immune mediated. To our knowledge, this is the first report of NGE affecting the orbital region of a dog. Development of absolute KCS resulting from excision of the nictitating membrane is also supported by this case. 相似文献
999.
Adriana Schultz Moreira Laura González-Torres Raul Olivero-David Sara Bastida Juana Benedi Francisco J. Sánchez-Muniz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):290-298
The effects of diets including restructured meats (RM) containing Wakame or Nori on total liver glutathione status, and several
antioxidant enzyme gene expressions and activities were tested. Six groups of ten male growing Wistar rats each were fed a
mix of 85% AIN-93 M diet and 15% freeze-dried RM for 35 days. The control group (C) consumed control RM, the Wakame (W) and
the Nori (N) groups, RM with 5% Wakame and 5% Nori, respectively. Animals on added cholesterol diets (CC, CW, and CN) consumed
their corresponding basal diets added with cholesterol (2%) and cholic acid (0.4%). Alga and dietary cholesterol significantly
interact (P < 0.002) influencing all enzyme expressions but not activities. The cholesterol supplement decreased most enzyme expression
and activity. W-RM vs. C-RM increased (P < 0.05) expression of GPx, GR, Mn-SOD, and Cu,Zn-SOD and decreased that of catalase. N-RM vs. C-RM increased (P < 0.05) expression of catalase and Mn-SOD. GR activity increased in W-RM rats while SOD activity increased, but that of Se-GPx
decreased in N animals. W-RM increased total and reduced glutathione and decreased the redox index. CN diet induced significantly
lower plasma cholesterol levels (P < 0.001) than the CW diet. In conclusion, Nori-RM is a hypocholesterolemic food while Wakame-RM is an antioxidant food. This
should be taken into account when including this kind of RM as potential functional foods in human. 相似文献
1000.
Inge M. Hanssen Rick Mumford Dag-Ragnar Blystad Isabel Cortez Beata Hasiów-Jaroszewska Dimitrinka Hristova Israel Pagán Ana-Maria Pereira Jeff Peters Henryk Pospieszny Maja Ravnikar Ineke Stijger Laura Tomassoli Christina Varveri René van der Vlugt Steen Lykke Nielsen 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(2):145-152