首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 671 毫秒
1.
The milling potential of hulled barley, hulled oat, triticale, rye and wheat was studied using a long tempering process and a laboratory four-roller mill. Regardless of the investigated cereal, the results indicated a significant influence (p < 0.05) of volume per surface area ratio on the milling yield and ash contents of the flour. The lowest milling yield was obtained in case of hulled oat. Solvent retention capacity profiles were determined for all investigated whole cereals and flours for predicting the contribution of different polymers to the functionality of samples. For all solvents higher values were obtained for the whole cereals compared to the corresponding flour. Thermo-mechanical properties of the whole cereals and refined flours were also investigated. If in case of wheat the gluten proteins play an essential role on dough behaviour during kneading at 30 °C, in case of triticale, rye, hulled barley and hulled oat, the fibers play a major role as well. Thermo-mechanical properties of starch registered a large variation between cereals and/or flours. The lowest torque value corresponding to starch gelatinization (C3) was registered in case of the hulled oat flour, 1.92 Nm, while the highest value in case of rye flour, 2.65 Nm.  相似文献   

2.
3.
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, squalene, and tocopherols. The objective of the present study was to determine the levels of phytosterols, and squalene, as well as tocopherols (α and β + γ) in selected grains, seeds, and legumes. The method comprised acid hydrolysis and lipid extraction followed by alkaline saponification, prior to analysis by HPLC. In addition, the fatty acid profile of the foods was determined via total lipid extraction, fatty acid derivitisation and GC analysis. In general, β-sitosterol was the most prevalent phytosterol, ranging in concentration from 24.9 mg/100 g in pumpkin seed to 191.4 mg/100 g in peas. Squalene identified in all foods examined in this study, was particularly abundant in pumpkin seed (89.0 mg/100 g). The sum of α- and β+ γ-tocopherols ranged from 0.1 mg/100 g in rye to 15.9 mg/100 g in pumpkin seeds. Total oil content ranged from 0.9% (w/w) in butter beans to 42.3% (w/w) in pumpkin seed and the type of fat, in all foods examined, was predominantly unsaturated. In conclusion, seeds, grains, and legumes are a rich natural source of phytosterols. Additionally, they contain noticeable amounts of squalene and tocopherols, and in general, their fatty acid profile is favorable.  相似文献   

4.
Four kinds of natural dying solutions (natural colorant extracts) were obtained by extraction from gardenia, coffee sludge, Cassia tora. L., and pomegranate using water at 90°C for 90 min with a liquor ratio (solid natural colorant material/solvent water, weight ratio) of 1/10. The dyeing, colour fastness, and deodorizing properties of cotton, silk, and wool fabrics dyed with natural colorant extracts were compared. It was found that these properties were significantly dependent on the concentration of extracts, the structure of colorant, and the kind of fabrics. The order of colour strength (K/S) is Cassia tora. L., pomegranate, coffee sludge, and gardenia. Colour fastness (light, water, and perspiration fastness) was in the range of 2nd–5th grades. The deodorizing performance of fabrics dyed with various natural colorant extracts was in the range of 50–99 %. The deodorizing performance increased in the order of gardenia < Cassia tora. L. < coffee sludge < pomegranate. Especially, the deodorizing performance of all fabrics dyed with pomegranate was found to be highest at 99 %.  相似文献   

5.
Sea cucumbers produce numerous compounds with a wide range of chemical structural diversity. Among these, saponins are the most diverse and include sulfated, non-sulfated, acetylated and methylated congeners with different aglycone and sugar moieties. In this study, MALDI and ESI tandem mass spectrometry, in the positive ion mode, were used to elucidate the structure of new saponins extracted from the viscera of H. lessoni. Fragmentation of the aglycone provided structural information on the presence of the acetyl group. The presence of the O-acetyl group was confirmed by observing the mass transition of 60 u corresponding to the loss of a molecule of acetic acid. Ion fingerprints from the glycosidic cleavage provided information on the mass of the aglycone (core), and the sequence and type of monosaccharides that constitute the sugar moiety. The tandem mass spectra of the saponin precursor ions [M + Na]+ provided a wealth of detailed structural information on the glycosidic bond cleavages. As a result, and in conjunction with existing literature, we characterized the structure of five new acetylated saponins, Lessoniosides A–E, along with two non-acetylated saponins Lessoniosides F and G at m/z 1477.7, which are promising candidates for future drug development. The presented strategy allows a rapid, reliable and complete analysis of native saponins.  相似文献   

6.
Guayule (Parthenium argentatum Gray) is a perennial shrub native to the Chihuahuan Desert. While guayule traditionally has been cultivated for rubber, more recently it is being cultivated for its hypoallergenic latex. Other uses including termite resistant wood products and an energy source have also been identified. However, the effects of various agronomic practices, such as planting and harvesting dates, plant spacing, cutting height and frequency, irrigation frequency, and herbicide application, on latex concentration and yield of newly developed germplasm have not been reported. The objectives of this study were to determine the yield and concentration of latex, rubber, and resin of four guayule lines planted at two populations and two planting dates. Four guayule lines (AZ-1, AZ-3, AZ-5, and 11591) were transplanted at two dates (28 November 2000 and 7 June 2001) and two plant populations (27,000 and 54,000 plants ha?1). Treatments were replicated four times. Each treatment plot was subdivided into six subplots for harvesting at 6-month intervals beginning 1 year after transplanting. Results showed that transplanting date did not affect plant size or latex concentration or yield consistently. Instead, it appeared that the time of harvest (fall vs. spring) was more important. The sixth (last harvest) in the fall planting date and the fifth harvest date in the spring planting date were the optimum for plant biomass and latex, rubber, and resin concentrations and yields. The lines AZ-1 and AZ-3 were larger, whereas AZ-5 had higher latex and rubber concentrations than the control, 11591. The greater plant population (54,000 plants ha?1) had higher biomass, rubber, and resin yields than the lower population (27,000 plants ha?1) at the early harvest dates, but not at the later harvest dates (5 and 6). More studies must to be conducted to determine the optimum plant population and transplanting date for other newly developed guayule germplasm lines.  相似文献   

7.
Aloevera, chitosan, and curcumin were applied in alone and in combination with each others on cotton, wool and rabbit hair by exhaustion method for the assessment of their antimicrobial activity. The antimicrobial activity of these natural ingredients was better in peroxide treated cotton, formic acid treated wool/rabbit hair fibrous substrates than their corresponding intact ones. Aloevera shown better antimicrobial activity than chitosan and curcumin when applied alone and its antimicrobial activity was enhanced by addition of both chitosan and curcumin. The application of aloevera+chitosan+curcumin combination on peroxide treated cotton and formic acid treated wool/rabbit hair fibrous substrate was fast up to twenty five washing cycles.  相似文献   

8.
Scanning electron microscope (SEM) pictures of small millet starch granules showed more large polygonal and few small spherical or polygonal granules. The granules of small millets resembled those of rice starch granules. The size of the starch granules ranged from 0.8–10 m. The size of the granules was larger in barnyard millet and smaller in proso millet. Several granules showed deep indentation caused by protein bodies. SEM of starch isolated from 24 hour-germinated kodo millet showed pitting or pinholes at some points due to the attack of amylases (preferentially on bigger granules). Brabender viscoamylograph studies on small millet starches revealed that the gelatinization temperatures ranged from 75.8 to 84.9 ° C. Barnyard millet possessed lower amylograph viscosity, minimum breakdown, and relative breakdown values when compared to the other small millets.  相似文献   

9.
The possibility that sugar accumulation of potatoes stored at low temperatures may be linked to activation of cyanide-resistant respiration (CRR) was investigated. After a lag period of several days, continuous HCN treatment stimulated CO2 production of tubers stored in 20% O2. At 1°C in 20% O2, HCN treatment increased respiration over that effected by low temperature treatment. After several weeks of treatment, cyanide-stimulated CO2 production was greater at 1°C than at 10°C. Sucrose and malate levels of HCN treated tubers were sometimes higher than those of the 10°C control tubers, but they were always lower than those of the 1°C control tubers. This indicated that CRR alone could not account for the sugar increases at 1°C. Storage in 2% O2 blocked the increase in CO2 production and changes in constituents associated with HCN treatments in 20% O2. HCN treatment had no significant effect on chip color. The level of CRR was measured in freshly cut slices from Monona, Norchip, and Kennebec tubers previously stored at 10°, 5°, or 1°C for several months. Slices from tubers previously stored at 1°C had increased CRR, but there was no difference in CRR between the 5°C and 10°C treatments. Sugars accumulated at 5°C, again indicating that sugar accumulation in potatoes stored at low temperatures was at least partially independent of the activation of CRR.  相似文献   

10.
Potato plants of Russet Burbank, Oromonte and Red McClure varieties were studied in the San Luis Valley of Colorado to determine their dry matter and nutrient accumulation. The following observations were made in the 1967 growing season.
  1. Growth patterns for the three varieties were similar, but average growth rate of Oromonte and Red McClure was higher than that of Russet Burbank.
  2. Top growth reached its peak in 61, 55, and 50 days after emergence for Russet Burbank, Oromonte and Red McClure, respectively.
  3. In the 3 weeks before killing forst, tuber growth equalled 50% of maximum tuber dry weight for Russet Burbank and about 61% for Oromonte and Red McClure.
  4. Total N uptake with a yield of 300 cwt per acre was about 127 lb for each variety, assuming a linear relationship between tuber yield and nitrogen uptake. The tubers contained about 71% of the total N uptake.
  5. Total P uptake with a yield of 300 cwt per acre was about 16 1b for each variety, assuming a linear relationship between tuber yield and P uptake. The tubers contained about 83% of total P uptake.
  6. Total K uptake with a yield of 300 cwt per acre was 132, 187, and 147 lb (not significantly different) for Russet Burbank, Oromonte and Red McClure, respectively, assuming a linear relationship between tuber yield and K uptake. The Russet Burbank tubers contained 63% of the total K uptake and Oromonte and Red McClure about 52%.
  7. Tuber dry matter per cent increased during the season until 2 weeks before a killing frost (65 to 69 days after emergence). At harvest, the dry matter approximated 21% for the varieties studied.
  相似文献   

11.
The cyanobacteria or “blue-green algae”, as they are commonly termed, comprise a diverse group of oxygenic photosynthetic bacteria that inhabit a wide range of aquatic and terrestrial environments, and display incredible morphological diversity. Many aquatic, bloom-forming species of cyanobacteria are capable of producing biologically active secondary metabolites, which are highly toxic to humans and other animals. From a toxicological viewpoint, the cyanotoxins span four major classes: the neurotoxins, hepatotoxins, cytotoxins, and dermatoxins (irritant toxins). However, structurally they are quite diverse. Over the past decade, the biosynthesis pathways of the four major cyanotoxins: microcystin, nodularin, saxitoxin and cylindrospermopsin, have been genetically and biochemically elucidated. This review provides an overview of these biosynthesis pathways and additionally summarizes the chemistry and toxicology of these remarkable secondary metabolites.  相似文献   

12.
氮磷钾肥对稻米铁、锌、铜、锰、镁、钙含量和产量的影响   总被引:21,自引:2,他引:21  
 采用田间试验,在四川省西昌市用两个水稻品种研究了氮、磷、钾肥施用量对稻米中铁、锌、铜、锰、镁、钙含量和产量的影响。结果表明,稻米中铁、锌、铜、锰、镁、钙含量均随着施氮量增加先上升后下降,滇屯502的铁、锌、铜、锰、镁、钙含量和产量都以施用90 kg/hm2 N最高,稻谷产量以施用180 kg/hm2 N最高;而合系39的铁、锌、铜、锰、镁、钙的含量以施用180 kg/hm2 N最高,稻谷产量以施用270 kg/hm2 N最高,说明供试籼型品种滇屯502对氮肥的敏感性较粳型品种合系39强;磷肥明显降低了稻米中铁、铜、锰、钙的含量和产量,适量增施磷肥有利于增加稻米中镁的含量和产量;适量施用钾肥有利于提高稻米中铁、锌、铜、锰含量和产量,两供试品种铁、锌、铜、锰含量均以90 kg/hm2 K2O时最高,而钾肥明显降低了稻米中镁、钙的含量和产量。  相似文献   

13.
Leaf blades of perennial ryegrass ( Lolium perenne ) at five developmental stages, from unemerged to dead, were collected from cut swards grown under field conditions. Similarly, leaflets of white clover ( Trifolium repens ) at four developmental stages, from tightly folded to proximal to the youngest fully developed leaf, were collected. The leaves were analysed for N, P, K, Ca, Mg and Na.
In perennial ryegrass, the concentration of N declined by about half and those of P and K declined by about two-thirds, as leaves aged. By contrast, the concentration of Ca increased more than fivefold and that of Mg about twofold as leaves aged. The concentration of Na initially increased more than twofold but then declined as leaves died. In white clover the concentration of N declined by about 20% as leaves aged, while the concentrations of P and K declined by about 50%; the concentration of Ca increased about fivefold, that of Mg declined by about 15% and that of Na increased by about 15%.
The application of N increased the concentrations of N and K in ryegrass leaf blades at all stages of development. The application of P increased the concentrations of P and Na in the leaves of both species.  相似文献   

14.
The nonionic surfactant properties of ethoxylated azo dyes, such as cloud point and surface tension have been investigated. The synthesized ethoxylated azo dyes could dye polyester fabric without any special pre-treatment. When the average number of ethylene oxide (EO) in the ethoxylated azo dye reached 6, its fixation could exceed 90% from the thermosol dyeing process. The average degree of condensation of ethylene glycol in the chain was interrelated with the dyeing results and did not affect on the maximum absorption wavelength (λmax) of the polyoxyethylene dye. When the average length of polyoxyethylene chain decreased, the molecular weight of dyes became smaller and the fixation of dyes was improved.  相似文献   

15.
UPAS-120, a high yielding and early maturing variety of pigeon peas releasedby the Department of Plant Breeding, CCS Haryana Agricultural University, Hisar contained a significant amount of phytic acid, i.e. 886 mg/100 g. When it was subjected to various domestic processing and cooking methods viz. soaking (6, 12, 18 h), dehulling, ordinary as well as pressure cooking and germination (24, 36 and 48 h), a drastic decrease in level of phytic acid with a remarkable increase in the HCl-extractability of mono, divalent, andtrivalent ions, like calcium, phosphorus, and iron occurred. Germination (48 h) was found to be the best method for decreasing the phytic acid content, i.e.35 to 39 percent less than the control and significantly (p<0.05) increasingthe non-phytate phosphorus and HCl-extractable phosphorus. Pressure cooking of soaked-dehulled pigeon pea also rendered equally good results. The calcium, phosphorus and iron contents of pigeon pea seeds were 197.3, 473.1, and 9.91 mg/100 g, respectively; some losses varying from 3 to 9 percent were noticed when the legume was subjected to soaking, cooking, and germination but the maximum losses, i.e. 23 percent, occurred when the seeds were dehulled. However, HCl-extractability of Ca, P and Fe improved to a significant extent when the pigeon pea seeds were soaked, soaked-dehulled, cooked and sprouted which may have been due to decrease in the phytate content followed by processing and cooking. The significant negative correlations between the phytic acid and HCl-extractability of minerals of processed pigeon pea strengthens these findings.  相似文献   

16.
以玉米品种'掖单13'和'丹玉13'为试材,通过大田试验研究供试玉米的初生根和第1层至第9层次生根中的铁、锰、铜、锌和钠等元素的含量.结果表明:玉米根系中铁、锰、铜、锌和钠元素的平均值分别为6469,185,22,14,884mg/kg.玉米初生根中的铁元素与次生根相比其含量较低,锰、铜、锌和钠元素的含量较高,高于各次生根中的含量.玉米同一品种的不同类型根中各元素含量之间存在差异,不同品种相同类型根中的各元素含量存在相关关系.  相似文献   

17.
《Journal of Crop Improvement》2013,27(1-2):245-270
SUMMARY

Weeds pose a recurrent threat to agricultural productivity in both industrialized and developing countries. Weeds respond dynamically to all cropping practices, and therefore, the design and function of cropping systems plays a central role in the composition of weed communities. The unique and challenging nature of weed communities requires more integrated approaches to weed management than are currently being employed by most growers. Integrating weed management with cropping system design and application may be an effective approach to diversifying weed management systems. Each crop-weed system is a unique mix of genetics and biology and will respond dynamically to changes in management practices. Practices such as crop rotation, tillage, cover crops, and fertility management modify weed populations. The challenge is to integrate these and other practices with the best available control tactics to generate integrated management systems. Cropping system design provides an excellent framework for developing and applying integrated approaches to weed management because it allows for new and creative ways of meeting the challenge of managing weeds. Weed science must integrate the theories and application of weed management into cropping system design based on the unique characteristics of weed communities and the available weed management options.  相似文献   

18.
Plant Foods for Human Nutrition - The seeds of nine species belonging to the Fabaceae family (Cassia alata, Cassia uniflora, Cassia obtusifolia, Cassia tora, Crotalaria albida, Crotalaria juncea,...  相似文献   

19.
Twenty two lines/accessions belonging to 5 species ofCelosia were analysed for their nutritional and antinutritional composition. The nutrient contents, vitamin C varied from 18.8 to 53.6 mg/100 g, carotenoids 9.1 to 15.1 mg/100g, protein 2.1 to 5.9%, while the antinutritional factors, nitrate 0.18 to 0.46% and oxalate 0.98 to 3.93%. Moisture ranged 81 to 89%. Variation of these parameters with leaf position and the amino acids profile of some promising lines was also evaluated.  相似文献   

20.
An understanding of protein adsorption process is crucial for designing biomaterial surfaces. In this work, with the use of a quartz-crystal microbalance with dissipation monitoring, we researched the following: (a) the kinetics of adsorption on TiO(2) surfaces of three extensively described proteins that are relevant for metallic implant integration [i.e., albumin (BSA), fibrinogen (Fbg), and fibronectin (Fn)]; and (b) the competition of those proteins for adsorbing on TiO(2) in a two-step experiment consisted of sequentially exposing the surfaces to different monoprotein solutions. Each protein showed a different process of adsorption and properties of the adlayer-calculated using the Voigt model. The competition experiments showed that BSA displaced larger proteins such as Fn and Fbg when BSA was introduced as the second protein in the system, whereas the larger proteins laid on top of BSA forming an adsorbed protein bi-layer when those were introduced secondly in the system.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号