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1.
Phaseolin, the major globulin seed storage protein of common bean,Phaseolus vulgaris L., accounts for up to 50% of the total seed protein. The rapid accumulation of phaseolin in the maturing seeds begins about 14 days after flowering and continues for some 12–14 days longer. However, the amount and rate of phaseolin accumulation, related to variation in onset, length, termination, and rate of synthesis, have been shown to vary between genotypes.Only three phaseolin electrophoretic types, designated T, S, and C after the cultivars Tendergreen, Sanilac, and Contender, respectively, have been identified among over 100 cultivated accessions. The narrow ranges of molecular weights and isoelectric points of the 14 protein polypeptides of phaseolin, as well as the homology observed from peptide mapping, suggest that the phaseolin polypeptides are similar proteins. Based on the results of crosses among cultivars having the three electrophoretic patterns, the genes controlling the polypeptides of each of the phaseolin types appear to be tightly linked, inherited in a block and the alleles are codominant.Substantial variation in phaseolin content, based on estimations using rocket immunoelectrophoresis, has been found among bean lines. Although most segregating populations show continuous distributions and quantitative inheritance, some inbred backcross lines having enhanced phaseolin accumulation appear to carry a few genes with major effects. A single gene that reduces the amount of phaseolin to less than one-half of the normal levels has been identified recently in an accession of wildP. vulgaris.  相似文献   

2.
Essential oils from 22 aromatic plant species were tested for mortality of the mosquito larvae Culex quinquefasciatus. Lethal concentrations were determined for individual essential oils. Essential oils obtained from Thymus vulgaris, Satureja hortensis and Thymus satureioides plants showed the highest effect, with LC50 found lower than 50 μg/ml (33, 36 and 44 μg/ml, respectively). Analyses showed that majority substances for T. vulgaris were thymol and p-cymene (60.3 and 10.1%, respectively); carvacrol and γ-terpinene for S. hortensis (48.1 and 36.7%, respectively), and borneol and thymol for T. satureioides (30.3 and 32.5%, respectively).The selected essential oils also showed very good effectiveness with respect to mortality and percentage of adult emergence upon short-term exposure in water contaminated with lethal doses of individual oils. While there was 77% adult emergence from the larvae in the control, in T. vulgaris, T. satureoides and S. hortensis there was only 12.3, 15.3 and 16.0% adult emergence, respectively. High antioviposition effectiveness was found in all selected oils. Almost 100% deterrence of female oviposition was determined for all oils in concentrations of 0.02%. Significant differences were seen with tested concentrations of 0.01 and 0.005%, where the oil of T. vulgaris proved most effective (repellency about 99.8 and 62.3%, respectively).  相似文献   

3.
White kidney beans (Phaseolus vulgaris), cv Processor, contain a relatively high content of phaseolin (storage protein), lectins and a special group of glycoproteins as well as a considerable amount of protein-type trypsin inhibitors. Protein digestion of raw Processor beans in monogastrics, for example pigs, is disturbed by poorly digested, phaseolin lectins, which can bind to carbohydrates in brush border membranes of the small intestinal epithelium, and trypsin inhibitors. The effect of the germination of white kidney beans on lectins, phaseolin and trypsin inhibitors was studied in order to achieve a degradation of lectins, phaseolin and trypsin inhibitors and an increase ofin vitro enzymatic hydrolysis of the protein of bean flour. Therefore, whole bean extracts were examined throughout a germination period of up to seven days for their lectin and phaseolin pattern, lectin content, binding capacities of functional lectins towards brush border membranes and trypsin inhibitor content. In addition thein vitro enzymatic hydrolysis by pepsin and pancreatin of the protein from flours of (un)germinated white kidney beans was studied. SDS-PAGE demonstrated a degradation of E-lectins and a disappearance of L-lectins and phaseolin during germination. Results indicated a decrease of the lectin content by 85%, a loss of binding capacities of functional lectins towards brush border membranes by 91%, and a decrease of trypsin inhibitors by 76%, in bean flour after germination for seven days. A maximum inin vitro enzymatic hydrolysis of protein from bean flour was already established after germination for half a day.  相似文献   

4.
The full utilization of legumes as human food is limited by a deficiency of sulfur amino acids, low protein digestibility, low methionine bioavailability and the presence of anti-nutritional factors. A new cultivar ofPhaseolus vulgaris (Carioca 80) has 56.8% available methionine, compared with 29.3% availability in the parent cultivar Carioca. The total methionine content, denaturing gel electrophoretic patterns of methionine-containing proteins, and the percentage of phaseolins (the major storage proteins in Phaseolus) relative to the total protein are similar in the two cultivars. Although the digestibility of the two cultivars is similar, the increased biological value of Carioca 80 may indicate that there are differences in overall bean composition that affect protein hydrolysis and utilization. We suggest the tentative explanation that this is due to differences in the distribution of methionine in the methionine-containing proteins of the two cultivars.  相似文献   

5.
Carotenoids are pigments responsible for the yellow-reddish color of many foods and are related to important functions and physiological actions, preventing several chronic-degenerative diseases. The objective of this study was to confirm the carotenoid composition of jackfruit by high-performance liquid chromatography connected to photodiode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The main carotenoids were all-trans-lutein (24–44%), all-trans-β-carotene (24–30%), all-trans-neoxanthin (4–19%), 9-cis-neoxanthin (4–9%) and 9-cis-violaxanthin (4–10%). Either qualitative or quantitative differences, mainly related to the lutein proportion, were found among three batches of jackfruit. Since the fruits from batch A showed significantly lower contents for almost all carotenoids, it also had the lowest total carotenoid content (34.1 μg/100 g) and provitamin A value, whereas the total carotenoid ranged from 129.0 to 150.3 μg/100 g in the other batches. The provitamin A values from batches B and C were 3.3 and 4.3 μg RAE/100 g, respectively. The carotenoid composition of jackfruit was successfully determined, where 14 of the 18 identified carotenoids were reported for first time. Differences among batches may be due to genetic and/or agricultural factors.  相似文献   

6.
In vitro proteolysis was used to study the digestibility of the major seed protein phaseolin, and the trypsin inhibitor, purified fromPhaseolus vulgaris seeds. Whereas denatured phaseolin was fully digested by the enzymic method used [4], its native form was only partially digested. Trypsin inhibitor, both native and after heat treatment, was poorly digested. It was also found that native trypsin had some resistance to digestion conferred upon it by the presence of the inhibitor.  相似文献   

7.
Einkorn (Triticum monococcum L. subsp. monococcum) is an ancient wheat appreciated for its high proteins, carotenoids and tocols content. To better understand its potential for human consumption and food preparation, composition and pasting properties of 65 einkorn accessions, of different geographical origin but cultivated at S. Angelo Lodigiano (Italy), were evaluated. Eight Triticum turgidum and seven Triticum aestivum cultivars, belonging to different subspecies, were assessed as controls.On average, the einkorn samples had light seeds (25.0 mg/kernel), extra-soft texture (238.3 g), high protein content (18.2%), high ash content (2.35%), low SDS sedimentation volume (25.6 ml), high carotenoids (8.36 μg/g) and high yellow pigments (8.46 μg/g). The pasting parameters studied were peak viscosity (average: 2426 cP), breakdown (765 cP), final viscosity (2788 cP) and setback (1126 cP). Total amylose (25.7%) and total starch (65.5%) were also measured. Significant differences from the controls and a broad variation for all the traits analysed were observed. Einkorns from diverse geographical areas showed different mean values for all characters, apart from ash content.The good pasting properties, coupled with high proteins and carotenoids content, suggest that einkorn is particularly suited for the production of baby and specialty foods.  相似文献   

8.
Screening of natural biodiversity for the better quality traits are of prime importance for quality breeding programs. The objective of this investigation was to select candidate accession of bean having high concentrations of protein as well as macro and micro minerals with good cooking quality for use as parents in breeding programme for these compounds. Thirty-five accessions of bean (Phaseolus vulgaris L) were field grown and their seeds were analyzed for their cooking quality and nutritional composition. Wide variations were observed in most of the measurements e.g. protein (18.7–26.2%), iron (79.4–137.6 ppm) and hardness after cooking (4.65–9.88 Kg) suggesting that there are considerable levels of genetic diversity. Across all accessions the concentration of potassium was negatively correlated with protein (r = −0.43, P < 0.05). Concentrations of protein was significantly greater in accessions VIII, XIII and XIX compared to other accessions analyzed. Iron concentrations were greatest (137 ppm) in XIX and lowest (79 ppm) in XXVII. Lines with less cooking time were line III, X, XXVI, XXX and XXXI. Bean line XIX contains high protein (24.9%) with high zinc (33.3 ppm) and highest iron (137.6 ppm), but it has high hardness after cooking (7.32 kg). Four clusters were computed by cluster analysis that explained quite a good variation in the traits. The great variability for these attributes suggests that these selected accessions may be useful as parents in hybridization programs to produce bean with value-added traits. This information was also potentially useful for pulse breeders working on the development of new varieties.  相似文献   

9.
10.
The increasing demand for gluten-free products has favoured the design of numerous gluten-free bakery products which intended to mimic the quality characteristics of wheat bakery products. The objective of this study was to evaluate the nutritional pattern of gluten-free breads representative of the Spanish market for this type of products. The protein, fat and mineral content of the gluten-free breads showed great variation, ranging from 0.90 to 15.5 g/100 g, 2.00 to 26.1 g/100 g and 1.10 to 5.43 g/100 g, respectively. Gluten-free breads had very low contribution to the recommended daily protein intake, with a high contribution to the carbohydrate dietary reference intake. Dietary fiber content also showed great variation varying from 1.30 to 7.20 g/100 g. In vitro enzymatic hydrolysis of starch showed that the most predominant fraction was the rapidly digestible starch that varied from 75.6 to 92.5 g/100 g. Overall, gluten-free breads showed great variation in the nutrient composition, being starchy based foods low in proteins and high in fat content, with high glycaemic index.  相似文献   

11.
Successful development and adoption of transgenic cassava (Manihot esculenta Crantz) varieties in Africa depend on in vitro regeneration of landraces because of their agronomic value and amenability to genetic modification. The study investigated somatic embryogenesis from axillary bud and immature leaf-lobe explant and regeneration via shoot organogenesis in five cassava landraces. Landraces exhibited significant (P < 0.05) differences in frequencies of primary somatic embryo production, number of embryos per explant, and frequency of secondary embryos. The frequency of primary somatic embryogenesis ranged from 7.8 to 14.5%, whereas the number of embryos per explant varied from 5.3 to 10.6. However, only frequency of primary somatic embryos and number of embryos per explant showed significant (P < 0.05) differences when immature leaf lobe was used as explant. The frequency of primary somatic embryogenesis ranged from 42.7 to 49.2%, whereas number of embryos per immature leaf-lobe explant varied from 9.5 to 15.2 per explant. Secondary embryogenesis was cultivar-independent in the case of immature leaf-lobe explant. Cyclic and green (mature) embryogenesis showed no significant (P < 0.05) landrace differences in both axillary bud and immature leaf-lobe explants. Shoot regeneration from cotyledon of somatic embryos had significant (P < 0.05) landrace differences. The mean shoot-bud formation frequency of axillary bud and immature leaf-lobe explants was 51.4% and 37.2%, respectively. Root formation was efficient, with greater than 70% of shoots forming root in all landraces. Similarly, landrace differences were detected for the survival of acclimatized regenerated plants, with a mean of 94.7% for both explants. In conclusion, somatic embryos were produced from immature leaf and axillary bud explants of the landraces and the embryos were converted to plantlets via shoot organogenesis.  相似文献   

12.
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important and highly polyphagous pests of vegetables and other crops worldwide. Experiments were conducted in the laboratory and greenhouse to evaluate corn (Zea mays L.) as a banker plant for the predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae) to potentially control T. urticae. Choice and no-choice experiments were carried out to determine the host plant preference of an alternative prey, Oligonychus pratensis (Banks)(Acari: Tetranychidae) to corn and green bean (Phaseolus vulgaris L.). Results showed that O. pratensis adults strongly preferred corn as a host plant and posed no risk to green bean. F. acarisuga was found to fly at least 7.0 m to search for new preys on green bean plants, and over 176 F. acarisuga larvae per leaf were recorded at 14 d after dispersal. F. acarisuga proved to be an excellent predator of both T. urticae and O. pratensis. The predation by F. acarisuga to T. urticae and O. pratensis ranged from 43.7 to 67.9% and 59.2 to 90.3%, respectively, under laboratory conditions. In a non-cage study, 81.2% of T. urticae population was suppressed by F. acarisuga in reference to the control (cage treatment). The results showed that this banker plant system has potential for controlling T. urticae in greenhouse vegetable production.  相似文献   

13.
The effects of nitrogen (N) fertiliser on grain size and shape, starch and protein concentration, vitreosity, storage protein composition, and alcohol yield of two winter wheat varieties contrasting in endosperm texture were studied in a field trial in Herefordshire, UK in 2004. Averaged across varieties, the alcohol yield was 439 L/tonne for grain with a protein concentration of 11.5 g/100 g. The soft endosperm wheat variety Riband produced on average 7.7 L more alcohol per tonne of grain at a given protein concentration than the hard endosperm variety, Option. At the same time, N fertiliser was shown to have significant effects on alcohol production through its major influence on grain protein concentration. Averaged over both varieties, there was a reduction in alcohol yield of 5.7 L for each 10 kg increase in protein content per tonne of grain. The starch concentration of Riband was 2.9 g/100 g higher than Option at a given grain protein concentration, supporting its higher observed alcohol yields. A low conversion of starch to alcohol in this study (6.30 L/10 kg starch) compared to the theoretical value (6.61 L/10 kg starch) indicated that there is potential for improvement of this character. The traits relating to grain size and shape were principally influenced by genotype, and were not influenced by N fertiliser. Conversely, there were only minor genotypic effects on grain protein concentration and vitreosity. An important finding was that there were no interactions between variety and N treatment for any of the variables considered, indicating that the response of the two varieties to changes in applied N was the same, resulting in consistent differences in starch concentration and alcohol yield between genotypes at different levels of grain protein. An analysis of the composition of the wheat storage proteins by size-exclusion chromatography showed that the gliadins increased on average by 0.56 g per g increase in total grain protein and were quantitatively the major protein fraction, suggesting that selection for low gliadin content may be a desirable means by which to reduce grain protein, and thereby increase alcohol yield in wheat. The relationship between alcohol yield per unit area and applied N rate was described by a quadratic function and the maximum alcohol yield per unit area was ca. 3630 L/ha. Statistical analysis suggested that the economic optimum rate of N applied for grain yield was close to the optimum N rate for maximum alcohol productivity.  相似文献   

14.
A laboratory experiment was conducted with the poultry red mite Dermanysuss gallinae (De Geer) to assess the toxicity of a range of essential oils obtained from wild-growing plants in Tunisia to this pest. Details of the percentage essential oil yield from these plants were also recorded. For comparison, commercially sourced essential oil from Thymus vulgaris (L.) was also tested against D. gallinae after work elsewhere found this product to be acaricidal. Recently fed adult female D. gallinae were exposed to the essential oils at 0.1 mg oil/cm2 in Petri-dishes at 22 °C over a period of 24 h.Results showed that the yield of essential oil varied considerably depending upon the source plant. Whilst maximum yields of 0.5% were achieved, three of the seven wild plants selected provided yields of less than 0.1%. Similar variability was recorded with respect to the toxicity of the essential oils to D. gallinae. Three of the essential oils tested did not cause significant D. gallinae mortality (in comparison to the control). However, all other selected oils provided mortality levels statistically similar to the 90% mortality achieved with commercial T. vulgaris essential oil, with the oil from Pelargonium graveolens (L’Hér.) killing 100% of D. gallinae exposed to it. Essential oil from P. graveolens in particular may be suitable for further development as a D. gallinae acaricide alongside or in place of commercial thyme essential oil.  相似文献   

15.

Changes in the contents and composition of polyphenolics and resulting antioxidant activities of S. verbenaca by-products were investigated at three phenological stages (flowering, early fruiting and late fruiting stages). The highest accumulation of total phenolics was detected at the flowering stage (58.36 mg GAE/g DW). HPLC analysis of methanolic extracts showed the prevalence of methyl carnosate (821.45–919.82 μg/g DW) and rosmarinic acid (544.51–649.26 μg/g DW). Phenolic diterpenes (1056.90–1148.42 μg/g DW) was the most represented class of compounds. Three complementary tests namely, DPPH? (IC50 value, 49.22 μg/mL) and ABTS?+-radical scavenging assays (146.86 μM TE/mg) and FRAP reducing power test (188.93 mM Fe(II)/mg) were used to evaluate the antioxidant capacity and showed the best performance at the early fruiting period. The current study evidenced the significant effect of phenophase on antioxidants and contributed to valorize S. verbenaca extracts as a source of functional phenolic compounds.

  相似文献   

16.
Comparison of the seed oil of Moringa pterygosperma (moringa) and Sclerocarya birrea (marula) showed a marked difference in fatty acid composition and oxidative stability. Moringa, with 1000 ppm tocopherols, had an oil stability index (OSI) of 133 h at 110 °C while marula with 1000 ppm tocopherols yielded 37 h at 110 °C. This correlated well with the fatty acid composition of these two oils. Moringa had less than 1% polyunsaturates and marula had 6.7% of these oxidatively unstable materials. In addition, fatty acid compositions of seven species of moringa are presented. All of these species had levels of behenic acid ranging from 1 to 7% with oleic acid levels from 68 to 79%. The highest amount of polyunsatures was found in the moringa species was in Moringa drouhardii with 3.6%.  相似文献   

17.
Imazamox plus bentazon has the potential to provide broad spectrum weed control in dry bean (Phaseolus vulgaris L.). Field trials were conducted in Ontario over a two year period (2003 and 2006) to evaluate the effect of imazamox plus bentazon applied post-emergence at 25 + 600 and 50 + 1200 g ai ha−1 on black, brown, cranberry, kidney, otebo, pinto, white and yellow eye beans. Treatments included a non-treated check. All treatments were maintained weed free during the growing season. The eight market classes responded similarly to imazamox plus bentazon. Imazamox plus bentazon applied post-emergence caused less than 4% visible injury at 7, 14 and 28 days after treatment. Imazamox plus bentazon applied post-emergence did not have any effect on plant height, shoot dry weight, seed moisture content and yield of dry bean. Based on these results, imazamox plus bentazon at the proposed maximum use dose can be safely used for weed management in black, brown, cranberry, kidney, otebo, pinto, white and yellow eye bean production in Ontario. Additional research is needed to determine if cultivars within a market class of dry bean differ in their response to imazamox plus bentazon.  相似文献   

18.
B-Type avenin-like genes and proteins were characterized in 23 species of Triticeae. Southern blot analysis showed that the avenin-like genes belong to a multigene family. RT-PCR showed expression only in developing endosperms of wheat and related species, between 3 and 22 DPA (days post anthesis) with a peak between 11 and 15 DPA in wheat. The encoded proteins are cysteine-rich, containing 18–19 cysteine residues. An avenin-like protein from wheat was expressed in Escherichia coli, purified and used to raise polyclonal antibodies. These antibodies were used to detect b-type avenin-like proteins in endosperms of wheat and related species by western blotting.  相似文献   

19.
为了明确不同小麦地方品种耐镉(Cd)性的差异,采用水培方法,测定了长江中下游麦区32个小麦地方品种的苗期生长指标、叶绿素含量、荧光参数和光合参数,并对参试品种的Cd耐性进行了比较和聚类分析。结果表明,32个小麦地方品种镉耐性指数变异系数为10.4%~49.4%,耐Cd性差异较大。根据耐性指数可将参试品种分成耐镉型(7个)、较耐镉型(4个)、中间型(6个)、镉较敏感型(8个)、镉敏感型(7个)5组。  相似文献   

20.
Bromelia pinguin L. is a plant native to Sinaloa, Mexico, where its fruit is used as food or as a phytotherapeutic agent. The fruits of B. pinguin were characterized and they could be considered as a functional food. These fruits show an average weight of 13.7 g and a yellow color of high luminosity (b* = 43.2, L* = 74.5). The values for acidity (4.6%, as citric acid) and pH (3.7) of B. pinguin fruit are similar to those of citrics. The edible portion is characterized by a high content of vitamin C (126 mg/100 g), ash (10.6 g/100 g d.w.), crude fiber (3.4 g/100 g d.w.), calcium (1290 mg/100 g d.w.), magnesium (500 mg/100 g d.w.), manganese (2.95 mg/100 g d.w.) and it is a good source of zinc (2.8 mg/100 g d.w.). Polar fractions extracted from the pulp fruit showed activity against several genera of human pathogenic-bacteria (Staphylococcus, Streptococcus, Enterococcus, Salmonella, Shigella, Escherichia and Pseudomonas).  相似文献   

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