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281.
Segall SD Artz WE Raslan DS Jham GN Takahashi JA 《Journal of agricultural and food chemistry》2005,53(25):9650-9655
The triacylglycerol (TAG) composition of coffee beans (Coffea canephora P.) was determined by reversed phase liquid chromatography-mass spectrometry and tandem mass spectrometry. The TAGs were separated on a Microsorb RP C-18 column in series with a Supelcosil RP C-18 column using isocratic elution with acetonitrile/2-propanol/hexane (v/v/v, 57:38:5) as the mobile phase at a flow rate of 1 mL/min for 100 min. Under these conditions, 13 TAGs were identified (elution order): trilinoleyl-glycerol (LLL, 11.76%), dilinolenoyl-palmitoyl-glycerol (PLnLn, 2.94%), dilinoleyl-oleyl-glycerol (OLL, 7.77%), dilinoleyl-palmitoyl-glycerol (PLL, 25.90%), dipalmitoyl-linolenoyl-glycerol (PPLn, 1.66%), dioleoyl-linoleyl-glycerol (OOL, 1.68%), dilinoleyl-stearyl-glycerol (SLL, 8.28%), palmitoyl-oleyl-linoleyl-glycerol (POL, 8.76%), dipalmitoyl-linoleyl-glycerol (PPL, 13.74%), dilinoleyl-arachidyl-glycerol (ALL, 3.51%), trioleoyl-glycerol (OOO, 2.33%), palmitoyl -linoleyl-stearyl -glycerol (PLS, 8.73%), and distearoyl-linolenonyl-glycerol (SSLn, 2.91%). The relative composition (%) was obtained directly from the data system with the photodiode array detector. 相似文献
282.
Bierhals JD Lajolo FM Cordenunsi BR Oliveira do Nascimento JR 《Journal of agricultural and food chemistry》2004,52(24):7412-7418
Unripe bananas have a high content of starch (almost 20%) that is metabolized during fruit ripening with a concomitant synthesis of soluble sugars. Since starch granules are composed of amylose and amylopectin, several enzymes have to be involved in its mobilization during banana ripening, with a necessary participation of one starch-debranching enzyme (DBE) to hydrolyze the alpha-1,6-branches of amylopectin. Banana DBE seems to be an isoamylase-type enzyme, as indicated by substrate specificity and the cloning of a 1575 bp cDNA, similar to the isoamylase sequences from potato, Arabdopsis, and maize. The assays for DBE indicated only minor changes in activity during ripening, and the results of the northern and western blots with antiserum against the recombinant banana isoamylase were in agreement with the steady-state level of activity, since no significant changes in gene expression were observed. The high activity on beta-limit dextrin and the similarity to the potato isoform 3 suggest that during banana ripening the hydrolysis of alpha-1,6-linkage of amylopectin results from the activity of a pre-existing isoamylase-type debranching enzyme in coordination with other amylolitic enzymes. To the best of our knowledge, this is the first evaluation of activity and expression of a DBE from a fruit. 相似文献
283.
Baoxin Chang Benjamin Wherley Jacqueline Aitkenhead-Peterson Jason West 《Journal of plant nutrition》2020,43(16):2480-2492
AbstractGiven the growing adoption and use of recycled irrigation across the turfgrass industry, there is importance in understanding the effects of irrigation chemistry on N uptake efficiency as it relates to various soluble N sources. The objective of this study was to determine interactive effects of three soluble N sources (ammonium sulfate, potassium nitrate, and urea) and three irrigation water sources (reverse osmosis (R.O.), sodic potable, and 2.5 dS m?1 saline (SA)) on turfgrass performance and 15N nitrogen uptake efficiency following foliar N fertilization. Results demonstrated that although all water and N source treatments produced above-acceptable levels of quality in Champion bermudagrass, both N and water source significantly impacted nitrogen uptake efficiency. Following an eight-hour uptake period, approximately 40 to 70% of foliar-applied N (from a 0.5?g N m?2 application) was recovered across all N sources. The highest uptake efficiency was noted with ammonium sulfate and urea treatments, with noticeably lower recoveries of N detected with potassium nitrate fertilization. Ammonium sulfate produced similar or improved turf quality to other N sources under R.O. and sodic potable irrigation, but reduced turf quality and green cover under saline irrigation. When water sources containing moderately high salinity levels (2.5 dS m?1) are used, potassium nitrate (KNO3) may provide the greatest turfgrass quality, however, its uptake efficiency may be lower than other N sources. The results suggest that soluble N source and tank mix and/or irrigation water chemistry may be important considerations for maximizing foliar uptake efficiency and minimizing potential for environmental loss. 相似文献
284.
A. Nicholas E. Birch Bryan S. Griffiths Sandra Caul Jacqueline Thompson Lars H. Heckmann Paul H. Krogh Jrme Cortet 《Pedobiologia》2007,51(3):251-ECOGEN
The interactions of genetically modified (GM) crops with soil species and ecosystems is complex, requiring both specific and broad spectrum assessments. In the ECOGEN project we undertook experiments at three scales of increasing complexity, using Bt maize expressing the Cry1Ab protein from Bacillus thuringiensis as an example. Test species were selected for laboratory-scale experiments to represent taxonomic groups that we could also monitor at glasshouse and field scales (e.g., nematodes, protozoa, micro-arthropods, earthworms, and snails). In the laboratory, single species were exposed to purified Cry1Ab protein or to Bt maize leaf powder incorporated into simplified diets under controlled conditions. In the glasshouse, multiple test species and soil microbial communities taken from ECOGEN's field sites were exposed to Bt maize plants growing under glasshouse or mesocosm conditions. In the field, evaluations were conducted on our selected indicator groups over multiple sites and growing seasons. Field evaluation included assessment of effects due to the local environment, crop type, seasonal variation and conventional crop management practice (tillage and pesticide use), which cannot be assessed in the glasshouse. No direct effects of Cry1Ab protein or Bt leaf residues were detected on our laboratory test organisms, but some significant effects were detected in the glasshouse. Total nematode and protozoan numbers increased in field soil under Bt maize relative to conventional maize, whilst microbial community structure and activity were unaffected. Field results for the abundance of nematodes and protozoa showed some negative effects of Bt maize, thus contradicting the glasshouse results. However, these negative results were specific to particular field sites and sampling times and therefore were transient. Taking the overall variation found in maize ecosystems at different sites into account, any negative effects of Bt maize at field scale were judged to be indirect and no greater than the impacts of crop type, tillage and pesticide use. Although the ECOGEN results were not predictive between the three experimental scales, we propose that they have value when used with feedback loops between the scales. This holistic approach can used to address questions raised by results from any level of experimentation and also for putting GM crop risk:benefit into context with current agricultural practices in regionally differing agro-ecosystems. 相似文献
285.
Bianca DiSabatino Jacqueline M. Parr Georgia Kritikos Gabrielle Monteith Adronie Verbrugghe 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(4):374
Thiamine is an essential dietary nutrient in cats; however, studies on the stability of thiamine in pet food are limited. The objective of this study was to analyze thiamine concentrations in commercial feline extruded diets over time at room and freezing temperatures. Twelve diets were split in half and thiamine concentrations were assessed using fluorometry. One half of each diet was then stored at room temperature (24°C) and the other half was frozen (−20°C). Subsamples were analyzed at 2 other time points at 6-month intervals up to 1 year. Data were assessed using a mixed procedure (2-factor factorial model with factors time and treatment). Based on F-tests, thiamine concentrations decreased over time (P = 0.001), with no treatment*time interaction (P = 0.9534). In conclusion, regardless of treatment, thiamine degraded at a similar rate over time. 相似文献
286.
Holland PT Cargill A Selwood AI Arnold K Krammer JL Pearce KN 《Journal of agricultural and food chemistry》2011,59(10):5248-5256
Immunoglobulin-containing food products and nutraceuticals such as bovine colostrum are of interest to consumers as they may provide health benefits. Commercial scale colostrum products are valued for their immunoglobulin G (IgG) content and therefore require accurate analysis. One of the most commonly used methods for determining total soluble IgG in colostrum products is based on affinity chromatography using a Protein G column and UV detection. This paper documents improvements to the accuracy of the Protein G analysis of IgG in colostrum products, especially those containing aggregated forms of IgG. Capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) analysis confirmed that aggregated IgG measured by Protein G does not contain significant amounts of casein or other milk proteins. Size exclusion chromatography identified the content of soluble IgG as mainly monomeric IgG and aggregated material MW > 450 kDa with small amounts of dimer and trimer. The turbidity of the eluting IgG, mainly associated with aggregated IgG, had a significant effect on the quantitative results. Practical techniques were developed to correct affinity LC data for turbidity on an accurate, consistent, and efficient basis. The method was validated in two laboratories using a variety of colostrum powders. Precision for IgG was 2-3% (RSD(r)) and 3-12% (RSD(R)). Recovery was 100.2 ± 2.4% (mean ± RSD, n = 10). Greater amounts of aggregated IgG were solubilized by a higher solution:sample ratio and extended times of mixing or sonication, especially for freeze-dried material. It is concluded that the method without acid precipitation and with turbidity correction provides accurate, precise, and robust data for total soluble IgG and is suitable for product specification and quality control of colostrum products. 相似文献
287.
The black vine weevil Otiorhynchus sulcatus (Coleoptera: Curculionidae) is a well-known insect pest causing damages and economic losses on various horticultural plants.
In recent times, numerous other weevils like O. rugosostriatus, O. raucus, O. ovatus or O. salicicola are becoming increasingly important in horticulture. We applied mark-release-recapture studies to estimate population size,
survival rates, aggregation patterns and dispersal capabilities of adult O. raucus and O. rugosostriatus in a commercial plantation of perennial ornamental plants. Knowledge of these characteristics is important for the correct
timing and design of efficient control strategies. Of 191 individually coded O. raucus and 340 O. rugosostriatus, 30 and 24%, respectively, were recaptured at least once over a period of 96 days. The majority of weevils were recaptured
within 2–3 m away from their release point and thus both species can be regarded as being quite sedentary. In accordance,
patchiness of weevil distribution was clearly evident in the study area. Population sizes reached maximum values after the
peak of adult emergence from pupae in spring (for O. raucus) and late summer (for O. rugosostriatus), with high survival rates being evident in particular for O. raucus. This study provides for the first time data on population ecology of two weevil species, whose abundance and importance
as putative insect pests in horticulture has increased over the last years. 相似文献
288.
Loderstedt S Benigni L Chandler K Cardwell JM Rusbridge C Lamb CR Volk HA 《Veterinary journal (London, England : 1997)》2011,190(3):359-363
Chiari-like malformation (CM) and syringomyelia (SM) is an important disease complex in the Cavalier King Charles Spaniel (CKCS) but data about the anatomical distribution of SM along the spinal cord are lacking in veterinary medicine. The objective of this study was to define the anatomic distribution of SM in CKCS clinically affected by CM/SM. Magnetic resonance imaging (MRI) of the brain and the entire spinal cord of 49 dogs was performed and different morphological parameters compared.Syrinx formation was present in the C1–C4 region and in other parts of the spinal cord. The maximal dorsoventral syrinx size can occur in any region of the spinal cord and the total syrinx size was positively correlated with age. Seventy-six per cent of CKCS with a cranial cervical syrinx also have a syrinx affecting more caudal spinal cord regions. MRI restricted to the cervical region may underestimate the extent of SM and the severity of the disease process in the majority of dogs. 相似文献
289.
290.