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51.
Due to the growing interest in the role of carotenoids in human health, their qualitative and quantitative analysis in foods is becoming more and more important. High-performance liquid chromatography has become the method of choice for the determination of these phytochemicals. A crucial step prior to the chromatographic separation is the quantitative extraction from the food matrix which was proven to be impeded in durum wheat. To optimize the extraction procedure, several factors with influence on extractability of carotenoids were investigated. Finally, it was shown that soaking of samples in water for 5 min prior to extraction with organic solvents had the strongest impact on extraction yield and led to the most rapid and gentle method. Contents of carotenoids in the extracts of several durum wheat and corn samples were doubled by soaking in water before extracting with methanol/tetrahydrofuran (1/1, v/v). In light of these findings, literature data on contents of carotenoids in cereal grains have to be viewed critically regarding the extraction procedures employed. 相似文献
52.
The effects of H2 gas treatment of an agricultural soil cultivated previously with a mixture of clover (Trifolium pratense) and alfalfa (Medicago sativa) on CO2 dynamics and microbial activity and composition were analyzed. The H2 emission rate of 250 nmol H2 g−1 soil h−1 was similar to the upper limit of estimated H2 amounts emitted from N2 fixing nodules into the surrounding soil ([Dong, Z., Layzell, D.B., 2001. H2 oxidation, O2 uptake and CO2 fixation in hydrogen treated soil. Plant and Soil 229, 1-12.]). After 1 week of H2 supply to soil samples simultaneously with H2 uptake net CO2 production declined continuously and this finally led to a net CO2 fixation rate in the H2-treated soil of 8 nmol CO2 g−1 soil h−1. The time course of H2 uptake and CO2 fixation in the soils corresponded with an increase in microbial activity and biomass of the H2-treated soil determined by microcalorimetric measurements, fluorescence in situ hybridization analysis (FISH) and DNA staining (DAPI). Shifts in the bacterial community structure caused by the supply of H2 were recorded. While the H2 treatment stimulated β-and γ-subclasses of Proteobacteria, it had no significant effect on α-Proteobacteria. In addition, FISH-detectable bacteria of the Cytophaga-Flavobacterium-Bacteroides phylum increased in numbers. 相似文献
53.
We examined collembolan food preference for fungal mycelium grown on copper-contaminated medium, and the relationship between copper content, food selectivity and collembolan fitness when fed contaminated mycelium.To clarify whether collembolan food selectivity is related to fitness parameters, Folsomia candida were fed mycelium of the dark-pigmented fungus Alternaria alternata grown on medium with different copper concentrations. Copper-contaminated food (fungus grown on 50, 125, 250 and 500 μg Cu g?1 medium, fresh wt.) was offered together with untreated food for 4 weeks. F. candida fed selectively on the provided mycelium and discriminated clearly between mycelium grown on high and low levels of contamination, distinctly preferring fungus grown on medium with a total copper concentration of 50 and 125 μg g?1. In contrast, fungus grown on highly contaminated medium (250 and 500 μg g?1) was avoided. Collembolan food preference generally matched fitness parameters. Reproduction was significantly affected by the total copper concentration of the fungal growth medium. When fed their preferred mycelium, collembolan reproduction was enhanced, whereas a diet of highly contaminated mycelium (250 or 500 μg g?1) resulted in a strong decrease in reproduction. Adult survival was affected only marginally. Even though heavy metal contamination is a potential stress factor for many soil microarthropods, F. candida is able to discriminate between high and low quality food sources, and even benefits from moderately elevated copper concentrations. 相似文献
54.
Susanne Lier Hansen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):103-109
Some of the chemical changes inside the bulb of onions (Allium cepa L.) and the influence of various harvesting criteria on dry matter content and composition were studied during long-term storage. Onion weight, dry matter content, total N and the non-structural carbohydrates, glucose, fructose, sucrose and total fructans were examined. Significant (P<0.05) interseasonal differences were observed in the weight of the onions, dry matter content, glucose and total non-structural carbohydrates. Furthermore, the dry matter content and composition differed inside the onion bulbs depending on the length of the storage period. The stage of maturation at the time of harvest also significantly influenced the weight of the onions, the dry matter content in individual onions and the fructose content. 相似文献
55.
Sharifah N. Syed Jaafar Johanna Baron Susanne Siebenhandl‐Ehn Thomas Rosenau Stefan Böhmdorfer Heinrich Grausgruber 《Plant Breeding》2013,132(6):546-552
Due to their antioxidant activity, anthocyanins are of increasing interest for nutritionists, food scientists and plant breeders. Anthocyanins in wheat grains are expressed in either the pericarp or aleurone layer. Previous studies revealed that different anthocyanins are present in wheat varieties carrying genes for either the purple pericarp or the blue aleurone trait. Progeny from crosses between red‐, purple‐ and blue‐grained wheat varieties were selected over several cycles for grain colour by visual scoring. Bulked F5 grains were evaluated for their total anthocyanin content by UV‐VIS spectrophotometry and HPLC‐MS. The results demonstrate that it is possible to increase the anthocyanin content by the combination of the different genetic backgrounds for purple pericarp and blue aleurone, even though the majority of progeny were within the range of the purple‐ and blue‐grained check varieties. Visual scoring for grain colour is efficient, reliable and fast for selection in early breeding generations. Advanced breeding lines with high anthocyanin content can be identified by simple extraction methods and spectrophotometric measurements. 相似文献
56.
Dennis N. Lozada R. Esten Mason Md Ali Babar Brett F. Carver Gina-Brown Guedira Keith Merrill Maria Nelly Arguello Andrea Acuna Lucas Vieira Amanda Holder Christopher Addison David E. Moon Randal G. Miller Susanne Dreisigacker 《Euphytica》2017,213(9):222
Genome-wide association studies (GWAS) are useful to facilitate crop improvement via enhanced knowledge of marker-trait associations (MTA). A GWAS for grain yield (GY), yield components, and agronomic traits was conducted using a diverse panel of 239 soft red winter wheat (Triticum aestivum) genotypes evaluated across two growing seasons and eight site-years. Analysis of variance showed significant environment, genotype, and genotype-by-environment effects for GY and yield components. Narrow sense heritability of GY (h 2 = 0.48) was moderate compared to other traits including plant height (h 2 = 0.81) and kernel weight (h 2 = 0.77). There were 112 significant MTA (p < 0.0005) detected for eight measured traits using compressed mixed linear models and 5715 single nucleotide polymorphism markers. MTA for GY and agronomic traits coincided with previously reported QTL for winter and spring wheat. Highly significant MTA for GY showed an overall negative allelic effect for the minor allele, indicating selection against these alleles by breeders. Markers associated with multiple traits observed on chromosomes 1A, 2D, 3B, and 4B with positive minor effects serve as potential targets for marker assisted breeding to select for improvement of GY and related traits. Following marker validation, these multi-trait loci have the potential to be utilized for MAS to improve GY and adaptation of soft red winter wheat. 相似文献
57.
58.
Jose M. Arjona Conxita Royo Susanne Dreisigacker Karim Ammar Joan Subirà Dolors Villegas 《Journal of Agronomy and Crop Science》2020,206(1):64-75
Flowering time is the most critical developmental stage in wheat, as it determines environmental conditions during grain filling. Thirty-five spring durum genotypes carrying all known allele variants at Ppd-1 loci were evaluated in fully irrigated field experiments for three years at latitudes of 41°N (Spain), 27°N (northern Mexico) and 19°N (southern Mexico). Relationships between weight of central grains of main spikes (W) and thermal time from flowering to maturity were described by a logistic equation. Differences in flowering time between the allele combination causing the earliest (GS100/Ppd-B1a) and the latest (Ppd-A1b/Ppd-B1a) flowering were 7, 20 and 18 days in Spain, northern Mexico and southern Mexico, respectively. Flowering delay drastically reduced the mean grain filling rate (R) and W at all sites. At autumn-sowing sites, an increase of 1°C in mean temperature during the first half of the grain filling period decreased W by 5.2 mg per grain. At these sites, W was strongly dependent on R. At the spring-sowing site (southern Mexico), W depended on both R and grain filling duration. Our results suggest that incorporating the allele combinations GS100/Ppd-B1a and GS105/Ppd-B1a (alleles conferring photoperiod insensitivity) in newly released varieties can reduce the negative effects of climate change on grain filling at the studied latitudes. 相似文献
59.
James Hinchcliffe Adam Powell Markus Langeland Aleksandar Vidakovic Ingrid Undeland Kristina Sundell Susanne P. Eriksson 《Aquaculture Research》2020,51(1):102-113
One approach to ongrow juvenile European lobster, Homarus gammarus, is to utilize land based rearing systems, incorporating automated feeding, individual culture and provision of stable pelleted feeds, preferably using sustainable ingredients. We initiated three feeding experiments to investigate the general suitability of ingredients produced from seafood by‐products as novel feeds for H. gammarus, in terms of promoting survival, development and growth of post‐larval lobsters from post‐larvae (PL) stage IV to the first juvenile stage (stage V). The first experiment was designed to screen an array of candidate, locally produced, novel protein sources on growth performance parameters. This initial experiment revealed that PL reared on a raw (i.e. wet, unprocessed shrimp) feed used as a reference showed superior performance to those reared on experimental feeds containing fishmeal, herring protein isolate or mussel meal; however, a novel type of shrimp meal, produced by flocculation from waste water, promoted the best PL performance of any experimental feed. A second experiment was designed to test the effect of drying method and to optimize the form of a wet shrimp reference feed used by lobster hatcheries. This showed that the performance of PL reared on experimental freeze‐dried shrimp feed was not significantly different to those reared on the wet, unprocessed shrimp used as a reference feed. However, lobsters offered experimental oven‐dried shrimp feed (with or without an immune supplement) resulted in significantly lower survival or growth performance. A third and final experiment was designed in an attempt to improve a candidate herring‐based protein source, by supplementing with nutrients found in shrimp. However, the results showed that PL reared on the wet reference shrimp feed still showed superior growth and survival than those reared on a herring feed alone, or supplemented with additives found in shrimp meal (either glucosamine, astaxanthin or both supplements combined). The high survival and growth, low incidence of moulting problems and high availability of waste shrimp material, suggest that non‐heat‐treated shrimp products are a promising feed ingredient for post‐larval European lobsters. 相似文献
60.
Susanne M. Stieger Christian Wenker Daniela Ziegler-Gohm Mark Flückiger PHD 《Veterinary radiology & ultrasound》2003,44(3):326-329
A 5-year-old guinea pig with suspected urolithiasis was presented for radiology and ultrasound examinations of the abdomen. Radiographically, an irregular-shaped mineral opacity was detected in the area of the urinary bladder. Ultrasonographically, pyelectasia of the right kidney, hydroureter with an ureterolith cranial to a thickened ureter wall close to the ureterovesical junction, and a thickened urinary bladder wall were detected. Histopathologically, the thickened ureter wall was found to be a papilloma. The ureter calculus consisted of 100% calcite. 相似文献