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1.
Quantitative variation in different fractions of seed proteins and their amino acid levels in populations ofVigna minima (Roxb.) Ohwi and Ohashi and inV. umbellata cv. IC 1568 — the rice bean — were investigated. Globulin I fraction, together with globulin II, constitutes 38 to 54 per cent of the total seed protein. The alkali soluble (glutelin) fraction is the second largest fraction. Both these fractions show broad range of variation, suggesting a broad genetic base. The profiles are population specific; the coastal population, which contains higher seed protein also possesses maximum levels of globulin I and glutelin fraction suggesting its potentiality for breeding lines with high protein content, high nutritive value, and salt tolerance. Protein content is positively correlated with globulin I and glutelin fractions, which are in turn positively correlated with each other. The amino acid profiles are specific not only to the fractions but also to the populations. The range of variation in the levels of all amino acids in different fractions is broad suggesting substantial genetic diversity. The average levels of lysine and sulphur amino acids are high in globulin I and glutelin fractions.  相似文献   

2.
为提高椰子加工副产物的利用,本研究从椰麸中依次提取4种组分蛋白,包括清蛋白、球蛋白、谷蛋白-1和谷蛋白-2.分析这4种组分蛋白的氨基酸组成,并利用SDS-PAGE技术分析其亚基组成和分子量.同时分析其表面疏水性,并研究不同离子强度对椰麸各组分蛋白的乳化性和乳化稳定性的影响.结果表明,椰麸蛋白质中清单白、球蛋白、谷蛋白-...  相似文献   

3.
Seven accessions of the underutilized legume, Cassia hirsuta L., seeds collected from seven different agroclimatic regions of Tamil Nadu, India, were analyzed for proximate composition, total proteins, protein fractions, mineral profiles and selected antinutritional factors. Crude protein ranged from 15.52 to 20.74%, crude lipid 3.77–7.04%, crude fiber4.68–6.92%, ash 3.98–6.42% and carbohydrates 62.45–70.16%. Energyvalues of the seeds were 1549–1634 kJ/100 g (DM), which are comparable to those of other legumes. Data on seed protein fractions revealed thatglobulins constituted the bulk of the seed protein as in most legumes. Mineralcontents of the seeds showed greater variation. Potassium was the mostabundant mineral (1029–1786 mg/100 g), whereas manganese was low (2.1–2.2 mg/100 g). Antinutritional factors such as total free phenolics,tannins, L-DOPA and lectins were analyzed. The results of the studydemonstrated that the accessions of C. hirsuta seeds collectedfrom Tamil Nadu, India, could be good sources of some important nutrientsfor humans.  相似文献   

4.
Studies on protein fractionation in seed coat, embryo, cotyledons and whole seed were made to observe the differences, if any, between chickpea and pigeonpea. Results indicated that globulin was the major fraction of embryo and cotyledons of these legumes. Seed-coat nitrogen was observed to be mostly comprised of nonprotein nitrogen and glutelin fractions and thus differed from other components in both chickpea and pigeonpea. The albumin fraction of cotyledons of both crops had the highest concentration of sulphur amino acids, methionine and cystine. Glutelin contained a considerably higher concentration of methionine and cystine than did globulin in chickpea and pigeonpea. This suggests that lines with higher glutelin should be identified to improve their protein quality. The amino acid compositions of different seed components did not show large differences between these two pulse crops.Submitted as JA no. 180 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).  相似文献   

5.
The effect of 7 days of germination on levels of nitrogenous and other nutrition related parameters, protein fractions and in vitro protein digestibility of fluted pumpkin (Telfairia occidentalis) seed was studied. The non-protein nitrogen gradually increased and the protein nitrogen content decreased during germination. Albumin and globulin fractions were found to be the major seed proteins of fluted pumpkin seeds, constituting about 58.6% of the total protein of the ungerminated (raw) seeds. The protein fractions, albumin and glutelin, were observed to increase by 61.5% and 57.0%, respectively, while a 54.6% decrease was noted in the prolamine fraction. The globulin fraction increased at the beginning of germination but decreased at the end. Germination significantly (p 0.05) increased the crude protein, nitrogen solubility and in vitro protein digestibility but decreased the fat, phytic acid and polyphenol contents of the seeds.  相似文献   

6.
辣木籽渣组分蛋白的理化与功能性质研究   总被引：1，自引：0，他引：1  
辣木籽渣是辣木籽提取油之后的副产物,为了提高其综合利用价值,本文以辣木籽渣为原料,通过奥斯本（Osborne）四步法提取清蛋白、球蛋白、谷蛋白和醇溶蛋白,分析比较了4种组分蛋白的理化性质及功能特性。结果表明：清蛋白、球蛋白、谷蛋白和醇溶蛋白的提取率分别为10.34%、0.69%、3.40%和3.65%,纯度均在82%以上,清蛋白、球蛋白、谷蛋白的分子量均较低（5~25 kDa）,且清蛋白的蛋白条带浓度最高。此外,清蛋白的溶解性、乳化性、乳化稳定性及起泡性均为最优,但泡沫稳定性最差,在静置120 min后消散。4种组分蛋白的持油性均受温度的影响,球蛋白受温度影响最小。本研究表明辣木籽渣是一种较优质的植物蛋白资源,可为其在食品工业的加工利用提供理论依据  相似文献   

7.
The effects of dry heat (roasting) and moist heat (boiling) on in vitro protein digestibility, protein fractions and other chemical properties of African breadfruit (Treculia africana Decne) seed that affect their utilization as a source of human food were investigated. Chemical analyses showed that the crude protein and fat contents of the unprocessed (raw) seeds were 20.1% and 13.7%, respectively. The level of phytic acid in the raw seed (1.19 mg/g) was lower than the levels found in some commonly consumed pulses in Nigeria. Albumin and globulin protein fractions were found to be the major seed proteins of African breadfruit seed, constituting 67.8% of the total protein of the raw seed. There were no significant (p<0.05) differences between crude protein, ash and fat contents of the raw and heat processed samples. Boiling proved more effective than roasting for improving protein digestibility and for reducing the levels of trypsin inhibitor, phytic acid and polyphenols of the samples. The complete removal of these antinutrients, however, would require a more severe heat treatment of the seed, which in turn would profoundly reduce the nutritional value and availability of proteins, as demonstrated by the low values obtained for in vitro protein digestibility, protein fractions and protein extractability.  相似文献   

8.
Six chickpea strains were analysed for their protein content and various protein fractions. The protein content ranged from 20.9–25.27%. Albumin, globulin, prolamin and glutelin contents ranged from 8.39–12.31%; 53.44–60.29%; 3.12–6.89% and 19.38–24.40% respectively. Salt soluble proteins (albumin + globulin) and globulins resolved into 19–23 bands whereas albumin proteins resolved into 30–34 bands. The molecular weights of various polypeptides ranged from 10–91 kD. Amino acid analysis of total proteins revealed that glutamic acid was present in maximum concentration followed by aspartic acid and arginine. Just like other pulse proteins, chick pea proteins were also found deficient in sulphur containing amino acids.  相似文献   

9.
Four accessions of the lesser-known legume, Cassia obtusifolia L. (Sickle pod), collected from four different agroclimatic regions of Western Ghats, were evaluated for agrobotanical traits and chemical composition. Amongthe four accessions, the Keriparai accession had the highest values for plant height (cm), number of flowers per cluster, number of pods per cluster, pod length (cm), seeds per pod, seed weight (g) per pod and seed recovery percentage. Crude protein ranged from 18.56–22.93%, crude lipid was between 5.35–7.40%, crude fiber ranged from 6.83–9.45%, ash content ranged from 5.14–5.83% and carbohydrate varied from 57.00–60.69%. Globulins constituted the bulk of the seed protein as in most legumes. Mineral profiles, viz., sodium, potassium, calcium, magnesium, phosphorus, iron, copper, zinc and manganese ranged from 42.92–84.83, 758.05–1555.79, 559.92–791.72, 456.36–709.47, 629.13–947.79, 8.42–12.35, 0.93–2.06, 10.60–30.04 and 2.12–4.12 Mg/100 g seeds flour, respectively. Seed proteins of all accessions exhibited relatively high levels of non-essential and essential amino acids, with the exception of threonine. The in vitro protein digestibility of the legume ranged from 74.66 to 81.44%. Antinutritional substances such as total free phenolics ranged from 0.34–0.66%; tannins were between 0.47–0.60%, L-DOPA content ranged from 0.98–1.34%; trypsin inhibitor activity varied from 11.4–13.5 TIU/mg protein and chymotrypsin inhibitor activity ranged from 10.8–12.3 CIU/mg protein. Phytohemagglutinating activity also was assayed. Inconclusion, the accessions of C. obtusifolia, collected from Western Ghats, South India, could serve as a low-cost source of some important nutrients for humans. The antinutritional factors might have little nutritional significance, if the seeds are processed properly.  相似文献   

10.
The effect of heat treatment on the soluble protein content in oat groats (Kerstin commercial variety) was evaluated using asymmetric flow field-flow fractionation (AF4) in combination with online multiangle light scattering (MALS) and UV detection. The AF4 method was used to separate the monomeric proteins from globulin hexamer and aggregate proteins and β-glucan polysaccharides in the soluble oat protein fraction. The total amount of soluble protein (with respect to total protein) was reduced to 35.7 ± 4.5 wt. % in heat treated oats from 74.6 ± 5.3 wt. % in non-heat treated oats. The ratio of monomeric to globulin hexamer and aggregate proteins was reduced from 1.82 to 1.48 as a result of heat treatment. Sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed the selective elimination of protein bands associated with the albumin and prolamin protein fractions as a result of heat treatment. These results were supported through amino acid analysis by cation exchange chromatography coupled with UV detection which revealed a reduction in amino acid residues associated with prolamin. The globulin proteins were found to be less sensitive to heat treatment.  相似文献   

11.
大豆种子贮存蛋白组成及其相关分析   总被引：4，自引：2，他引：4  
周新安  盖钧镒 《大豆科学》1992,11(3):191-197
1988年选用14个,1989年选用15个蛋白质含量差异较大的主要为江淮地区的大豆品种,进行随机区组试验。大豆种子中球蛋白、清蛋白、醇溶谷蛋白以及谷蛋白的品种间平均分别为28.56％、7.50％、1.81％和5.71％,品种间变幅分别为6.08％、10.25％、1.03％和6.51％。清蛋白含量与全蛋白含量。谷蛋白含量与全蛋白含量之间显著正相关,清蛋白含量对种子全蛋白含量品种间差异的相对贡献最大,而球蛋白含量对品种间全蛋白含量差异的相对贡献最小。球蛋白含量与株高、分枝数和单株粒重存在显著的正相关;但株高和清蛋白含量、单株荚数及单株粒数和谷蛋白含量有显著负相关。  相似文献   

12.
Recently, screening of transglutaminase (TGase) treatment on several gluten-free cereals revealed significant improvements on the baking performances of buckwheat flour by promoting protein networks. In this study, the impact of TGase on the protein fractions of buckwheat flour was investigated in order to better understand the activity and specificity of the enzyme. Albumin, globulin, prolamin and glutelin fractions were extracted from the flour and incubated with TGase. Capillary electrophoresis, two dimensional (2D) gel electrophoresis and size exclusion chromatography (SEC) were performed on each fraction. Capillary electrophoresis and 2D gel electrophoresis revealed that buckwheat main storage proteins, i.e. 2S albumin, 13S and 8S globulin, were cross-linked after TGase treatment. SEC showed the presence of high molecular weight (HMW) protein polymers in the TGase-treated albumin and globulin fraction. Analysis of the amino acid composition of the fractions revealed high amounts of glutamine and lysine residues in all fractions. In conclusion, the increase in the average molecular weight of buckwheat proteins and the formation of HMW protein polymers after TGase treatment are responsible for the improved functionality of buckwheat flour in terms of breadmaking potential. The enzyme was revealed to be not fraction specific as all fractions were TGase-reactive.  相似文献   

13.
Recently, screening of transglutaminase (TGase) treatment on several gluten-free cereals revealed significant improvements on the baking performances of buckwheat flour by promoting protein networks. In this study, the impact of TGase on the protein fractions of buckwheat flour was investigated in order to better understand the activity and specificity of the enzyme. Albumin, globulin, prolamin and glutelin fractions were extracted from the flour and incubated with TGase. Capillary electrophoresis, two dimensional (2D) gel electrophoresis and size exclusion chromatography (SEC) were performed on each fraction. Capillary electrophoresis and 2D gel electrophoresis revealed that buckwheat main storage proteins, i.e. 2S albumin, 13S and 8S globulin, were cross-linked after TGase treatment. SEC showed the presence of high molecular weight (HMW) protein polymers in the TGase-treated albumin and globulin fraction. Analysis of the amino acid composition of the fractions revealed high amounts of glutamine and lysine residues in all fractions. In conclusion, the increase in the average molecular weight of buckwheat proteins and the formation of HMW protein polymers after TGase treatment are responsible for the improved functionality of buckwheat flour in terms of breadmaking potential. The enzyme was revealed to be not fraction specific as all fractions were TGase-reactive.  相似文献   

14.
During the malting process, storage proteins are degraded by proteolytic enzymes into small peptides and amino acids. The activity of these enzymes was measured during malting of oats and was found to be increased. To quantify proteolytic degradation, proteins of unmalted, germinating and malted grains were fractionated. After extracting the oat proteins (Osborne fractionation), protein fractions were analysed using a Lab-on-a-Chip technique, which separates the proteins – based on their molecular weight – by capillary electrophoresis. This new technique for the analysis of proteins was supported by using two-dimensional gel electrophoresis. In addition, amino acid analysis was carried out. In general a degradation of proteins to small peptides and amino acids could be observed in the globulin, prolamin and glutelin fractions. In the albumin fraction a protein increase was observed, which is due to the fact that this fraction contains the majority of the metabolically active proteins. Amino acid analysis supported the observation of increased protein amount in the albumin fraction and decreased protein amounts in the other fractions. Some proteins, which have not been described in the literature, were detected in the albumin and glutelin fraction, since Lab-on-a-Chip technique allows detection of proteins with low molecular weights of 4.5 kDa.  相似文献   

15.
Seeds ofCleome dolichostyla were analysed for proximate composition, mineral element contents and amino acid composition, in-vitro protein digestibility (IVPD) and calculated protein efficiency ratio (C-PER). The seeds (dry basis) were rich in oil (32.1%), protein (24.6%) and fiber (17.8%) content. The contents of various mineral elements mg/100 g) were: Ca=1970, P=493, Mg=127, Na=35, K=465, Fe=71.97, Zn=2.25, Cu=0.44 and Mn=1.45. Aspartic acid, glutamic acid, glycine, arginine and histidine were the major amino acids inC. dolichostyla seed protein accounting for half of the total amino acids. Lysine was the most limiting essential amino acid (FAO/WHO, 1973 reference pattern) with a chemical score of 45 for the protein. The IVPD of cleome seed protein was 72.2% and C-PER was 1.08 relative to the IVPD and C-PER values of 90.0% and 2.50 for the Animal Nutrition Research Council casein.  相似文献   

16.
Albumin, globulin, glutelin and prolamin fractions were isolated from an Australian rice variety (cv. Langi) and characterised by yield, protein content and molecular weight profile using both capillary electrophoresis (SDS-CE) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The influence of pre-extraction enzymatic hydrolysis of starch and heating to 70 °C was also investigated, as was the extraction of the glutelin fraction without prior removal of the albumin and globulin fractions. Pre-extraction treatment affected mainly the albumin fraction, increasing dry matter yield but reducing protein content. SDS-CE was able to separate the protein fractions over a wider molecular weight range than SDS-PAGE, and the peaks from SDS-CE showed slightly higher molecular weight compared to equivalent bands from SDS-PAGE. The glutelin fraction extracted without prior removal of albumin and globulin fractions had different characteristics compared to those obtained by conventional extraction methods. Pre-extraction hydrolysis of starch did not significantly affect the emulsifying, foaming and gelling properties of extracted protein. Although rice glutelin had poor solubility, emulsifying and foaming properties in aqueous systems, it had good gelling properties which could be important for food applications.  相似文献   

17.
Albumin and globulin fractions, obtained after modifications of the Osborne's fractionation scheme, were investigated in the seeds of three cultivars of Phaseolus vulgaris, after removal of the seed coats, to prevent interactions of tannins and phenols with the globulins. Also, by using an appropriate buffer to separate the globulins more efficiently, no cross-contaminations were observed in SDS-PAGE between these two fractions. The combination of these two procedures resulted in globulin to albumin ratios 70percnt higher than those published previously with the same cultivars. Amino acid compositions of total globulin, phaseolin and albumin fractions are presented. Whereas the albumins contained much more cysteine than the globulins, the concentrations of methionine were evenly distributed in these two fractions. Also, the bulk of methionine was found in phaseolin; cysteine was found in non-phaseolin proteins. In addition, the globulins contained unexpectedly high amounts of lysine.  相似文献   

18.
This study demonstrates variability in amino acid composition among accessions of several Philippine indigenous legumes. Moreover, two accessions ofD. lablab were identified to have high level of methionine (>2%). Methionine was identified as the first limiting amino acid with leucine, and threonine as the second limiting amino acids for most legumes studies.The IVPDs of the legumes under study ranged from >70 to 79%. Raw mature seeds had relatively low RNVs of 11 to 68% which increased to 68 to 94% and 51 to 89% after boiling and roasting, respectively.  相似文献   

19.
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   

20.
Total sulphur was determined in seed meal of 30 chickpea and 24 pigeonpea cultivars by the wet digestion procedure and by using the Leco sulphur analyser. Methionine and cystine were determined after performic acid oxidation in an amino acid analyser. The two methods used for total sulphur determinations were highly correlated (r=0.943). Percent meal protein was significantly correlated (r=0.476) with total sulphur in chickpea but not in the case of pigeonpea. Total sulphur content exhibited a significant positive correlation (r=0.651) with sulphur amino acids of pigeonpea when expressed as percent of protein but not in the case of chickpea. Correlation coefficients between total sulphur and sulphur amino acids when the results were expressed as percent of sample were positive for both chickpea (r=0.494) and pigeonpea (r=0.534). The amount of sulphur in methionine and cystine accounted for 54.8% of the total sulphur in chickpea and for 75.5% in pigeonpea. In both chickpea and pigeonpea, methionine was positively and significantly correlated with cystine when they were expressed either as percent of sample or as percent of protein.Submitted as J.A. no. 159 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).  相似文献   

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