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1.
The composition and contents of nutritional factors such as proteins, lipids, carbohydrates, fibers, amino acids, and antinutritional factors such as trypsin inhibitors, phytic acid, and tannins were compared in soybean and fababean seeds with emphasis placed on the nutritional improvement of the seeds by cortex removal. Protein hydrolysis analysis for both whole seeds and seed with cortex removed revealed the presence of a large amount of lysine, arginine, aspartic acid, glutamic acid, glycine, and leucine while these seeds contained a low level of tryptophan, cystine, and methionine. Some antinutritional factors such as trypsin inhibitors, phytic acid, and tannins were detected in soybean and fababean seeds: phytic acid content and trypsin inhibitor activity were higher in soybean seeds than in fababean seeds while the difference in the tannin content was less pronounced. It was found that most of the tannins occurred in the cortex of the soybean and fababean seeds. Tannins are polyphenolic compounds that readily form indigestible complexes with proteins and other macromolecules under specific environmental conditions. By removal of the cortex, tannins were almost completely eliminated without changes in the protein composition and amino acids. From these results, it is assumed that since soybean and fababean seeds contained a high concentration of antinutritional factors in the cortex such as tannins, the utilization of the legume seeds after removal of all of the cortex is suitable for human diet or industrial products.  相似文献   

2.
In addition to some histological observations, the chemical composition of Carica candicans Gray (Caricaceae) fruit and seeds, a plant common in Peruvian nutritional habits, was determined. The fruit contains high amounts of total proteins (8.2% on dry weight basis) and carbohydrates (70.1%) and appreciable contents of vitamin C and minerals. The oil extracted from seeds is in high amount (41. 6%). The fatty acid composition, with a prevalence of oleic, palmitic, and linoleic acids, suggests a possible use of this oil in alimentation.  相似文献   

3.
The stepwise hot water extraction of soybeans, which were extractions in a series of procedures of whole soybean seeds, dehulled and sliced ones, and pressed ones carried out by autoclaving, was investigated to study the localization in the seed and their characteristics. The characteristics of each extraction were studied by HPLC, SDS-PAGE, components analysis, microscopic observation, and effect for some enzymes. Carbohydrates were easier to extract than protein. In the extractions, the ratio of uronic acid per total sugar was constantly about 0.3. A comparison of these extracts, soybean milk, extraction from defatted soybean meal, and soybean milk residues was also carried out, and the characteristics and the localization were investigated. Mid-sized proteins in soybean milk were easy to extract. However, hardly any high molecular weight proteins or high molecular weight carbohydrates were extracted. The proteins and carbohydrates were considered to be localized in the middle lamella and in the protein and/or oil bodies of the cell, and the proteins and carbohydrates were gradually extracted through seed and cell breaking. Gelation was observed only in the boiled extracts from whole seeds. Pepsin and trypsin digests of the high molecular weight protein had inhibitory activity against the angiotensin I converting enzyme.  相似文献   

4.
6-苄基腺嘌呤对大豆内部水分分布及其生长状态的影响   总被引:1,自引:1,他引:0  
为研究大豆发芽过程中加入不同浓度的6-苄基腺嘌呤(6-Benzylaminopurine,6-BA)后大豆内部水分的分布及对其生长状态的影响,以中黄13为研究对象,在相同环境条件下,用浓度分别为0(对照)、1、3、5、7、9 mg/L的6-BA溶液处理大豆。利用低场核磁共振技术(Low Field Nuclear Magnetic Resonance,LF-NMR)对中黄13在浸泡8 h及萌发12、24、36、48、60 h时间点的波谱信息、图像信息进行采集,同时对豆芽的生长状态进行理化指标和形态指标检测。结果显示:与其他处理组相比,浓度为3 mg/L的6-BA溶液处理的大豆的发芽周期、吸水率、平均质量、发芽率、豆芽轴长、轴径各指标表现均为最优;低浓度(1、3 mg/L)6-BA加速大豆蛋白质的水解,导致其渗透势降低,促进大豆蛋白质体吸收更多的水分,进而促使豆芽轴长变长、轴径变粗;高浓度(5、7、9 mg/L)6-BA使大豆细胞壁在细胞的渗透作用下遭到破坏,导致大豆吸水率降低,进而抑制了大豆的生长。该研究从大豆原料的预处理开始对整个加工过程进行了研究,为豆芽的生产加工提供一定的理论支持和数据参考。  相似文献   

5.
Sicklepod (Senna obtusifolia) is a leguminous plant that infests soybean fields in the southeastern United States. Its seeds contain a variety of toxic, highly colored compounds, mainly anthraquinones together with a small amount of fat. These compounds contaminate and lower the quality of soybean oil when inadequately cleaned soybean seed from this area is processed. The sorting of sicklepod seed from a soybean harvest is an additional economic burden on the farmer beyond the cost of proper disposal of the weed seed to avoid worsening field infestation. Fortunately, sicklepod seed also contains substantial amounts of carbohydrates and proteins. These edible components when freed from anthraquinones have a market in pet food as well as potential in human foods because of the high galactomannan ratio of the polysaccharides. Sicklepod seed was dehulled, and the ground endosperm was defatted, followed by sequential solvent extraction of the defatted seed meal to isolate the anthraquinones, carbohydrates, and protein components into their respective classes. Each class of isolate was spectroscopically identified.  相似文献   

6.
The objective of this study was to investigate the influence of NaCl and two salt substitutes, MgSO4 and KCl, in different concentrations (1.5, 6.0, and 9.0%) on meat proteins by using Fourier transform infrared (FTIR) microspectroscopy. Hydration properties and secondary structural properties of proteins were investigated by studying the amide I, amide II, and water regions (3500-3000 cm(-1)) in FTIR spectra. By applying multivariate analysis (PCA and PLSR), differences between samples according to salt concentration and salt type were found and correlated to spectral bands. The most distinctive differences related to salt type were obtained by using the water region. It was found that samples salted with MgSO4 exhibited hydration and subsequent denaturation of proteins at lower concentrations than those salted with NaCl. Samples salted with KCl brines showed less denaturation even at the 9.0% concentration. The FTIR results were further supported by water-binding capacity (WBC) measurements.  相似文献   

7.
Structural changes of myofibrillar proteins from raw pork muscle and Cantonese sausage at different processing periods were elucidated using Raman spectroscopy. Fourier deconvolution combined with iterative curve fitting were used to analyze the amide I Raman band. Results from amide I, amide III, and C-C stretching vibrations in 890-1060 cm(-1) showed that α-helix decreased accompanied by an increase in β-sheet structure during the first 18 h, and a rebuilding process of secondary structures was observed at the rest stage due to proteolysis. The hierarchical cluster analysis results of amide I and amide III confirmed this rebuilding process. Changes in a doublet near 850 and 830 cm(-1) suggested that some tyrosine residues became buried in a more hydrophobic environment due to intermolecular interactions. Raman spectra in the 2855-2940 cm(-1) region suggested that the environment of aliphatic side chains might have been changed during the final stage and further confirmed above rebuilding process.  相似文献   

8.
Protease inhibitors play a protective role against pathogenic microorganisms and herbivorous insects. The two predominant protease inhibitors of soybean seeds are the Kunitz trypsin inhibitor (KTI) and Bowman-Birk protease inhibitor (BBI). In this study, we report that soybean seeds incubated in warm water release large amounts of proteins into the surrounding media. Two-dimensional gel electrophoresis analysis of the seed exudates resulted in the separation of 93 distinct protein spots out of which 90 spots were identified by LC-MS/MS. The basic 7S globulin and the BBI are the two predominant proteins found in the soybean seed exudates. In addition to 7S and 11S seed storage proteins, others known to protect the seeds against pathogens and pests including KTI, peroxidase, α-galactosidase, and endo-1.3-β-glucanase were also identified in the seed exudates. Soybean seed exudate obtained by incubating the seeds in warm water was also able to inhibit the growth of human breast cancer cell line MCF-7. Since soybean seeds release large amounts of enzymatically active BBI when immersed in warm water, our procedure could be exploited as a simplified alternative method for the preparation of BBI concentrate which is being used as a cancer chemoprotective agent.  相似文献   

9.
The seeds of 322 Korean soybean varieties were collected from six different cultivated sites in Korea and classified into three groups based on the 100-seed weight as small, medium, and large. Seeds were analyzed for their concentrations of isoflavones and phenolic compounds. The total average isoflavones in soybean cultivated at Iksan (2.840 micromol g(-1)) and phenolic compounds in soybean grown at Yeoncheon (9.216 micromol g(-1)) and Iksan (9.154 micromol g(-1)) were significantly different (p<0.05). In small and medium seeds of soybeans cultivated at Yeoncheon, Yesan, and Milyang high levels of isoflavones were obtained, whereas soybeans grown in Chuncheon showed the lowest isoflavone concentrations. However, isoflavone concentrations in the large seeds of soybean cultivated at Chuncheon showed the highest level. The soybean cultivated at Yeoncheon had high levels of phenolic compounds in small, medium, and large seeds, whereas the soybean grown at Chuncheon had the lowest. On the other hand, the phenolic concentrations of large soybean cultivated at Milyang were the least. At Yeoncheon, Yesan, and Milyang, the total isoflavone and phenolic compounds levels related to their seed size was significantly different (p<0.05), whereas in the soybean of different sizes cultivated at Chuncheon, the relationship to their seed size was not significantly different. The relationships of total isoflavones and phenolic compounds of small and medium soybean seeds were significantly higher than that of large soybean seeds. The hydroxybenzoic acid group in all sizes of seeds cultivated at six sites in Korea was the major phenolic compound, followed by flavonoid and hydroxycinnamic acid. The total isoflavone concentration was positively correlated with acetylglycoside and negatively correlated with malonylglycoside in the small soybean seeds cultivated at Yeoncheon. In medium soybean seeds cultivated at Yeoncheon, a significantly positive correlation was found between acetylglycoside and glycoside, between aglycone and glycoside, and between aglycone and acetylglycoside, whereas a significantly negative correlation was shown between malonylglycoside and glycoside, between acetylglycoside and malonylglycoside, and between aglycone and malonylglycoside. In large soybean seeds cultivated at Chuncheon, significantly positive and negative correlations were similar to those of medium seeds. The results presented here can improve the understanding of the relationships among the concentrations of individual chemical compounds and each chemical compound group and total chemical compounds in soybeans of different seed sizes from different cultivated sites.  相似文献   

10.
We determined and compared the composition and content of isoflavones in the cotyledon, hypocotyl, and root of 17 soybean sprout varieties grown under dark and light conditions. The total average isoflavone concentrations in 17 soybean sprout varieties were 2167 microg g(-1) (green sprout) and 2538 microg g(-1) (yellow sprout) in cotyledons, 1169 microg g(-1) (green sprout) and 1132 microg g(-1) (yellow sprout) in hypocotyls, and 2399 microg g(-1) (green sprout) and 2852 microg g(-1) (yellow sprout) in roots. There were no significant differences in total isoflavone concentrations between the green and yellow sprouts. However, significant differences in total isoflavone amounts were observed among the three organs, with roots exhibiting the highest total isoflavone concentrations followed by cotyledons and hypocotyls. Total daidzin concentrations of green (775 microg g(-1)) and yellow (897 microg g(-1)) sprouts increased to more than 4 times that in seeds (187 microg g(-1)). Yellow sprouts contained the highest (1122 microg g(-1)) total genistin concentrations, and green (155 microg g(-1)) and yellow (155 microg g(-1)) sprouts had more total glycitin concentrations than seeds. In cotyledons of green and yellow sprouts, genistin, daidzen, and glycitin constituted more than 67%, more than 28%, and less than 4% of the total isoflavone contents, respectively. In hypocotyls, total daidzin represented more than 45% of the total isoflavones, and total glycitin was higher than in cotyledons and roots. Malonylglycoside concentrations were highest in cotyledons, whereas glycoside concentrations were highest in hypocotyls and roots. The high accumulation of isoflavones in roots is consistent with isoflavones serving as signal molecules in the induction of microbial genes involved in soybean (Glycine max) nodulation.  相似文献   

11.
Hydroponic cultivation allows the control of environmental conditions, saves irrigation water, increases productivity, and prevents plant infections. The use of this technique for large commodities such as soybean is not a relevant issue on fertile soils, but hydroponic soybean cultivation could provide proteins and oil in adverse environmental conditions. In this paper, the compositions of four cultivars of soybean seeds and their derivates, soy milk and okara, grown hydroponically were compared to that of the same cultivar obtained from soil cultivation in an open field. Besides proximal composition, the concentrations of phytic acid and isoflavones were monitored in the seeds, soy milk, and okara. Results demonstrated that, independent from the cultivar, hydroponic compared to soil cultivation promoted the accumulation of fats (from 17.37 to 21.94 g/100 g dry matter) and total dietary fiber (from 21.67 to 28.46 g/100 g dry matter) and reduced isoflavones concentration (from 17.04 to 7.66 mg/kg dry matter), whereas protein concentration was unaffected. The differences found in seed composition were confirmed in the respective okara products, but the effect of cultivation system was not significant looking at the soy milk composition. Data showed that hydroponic cultivation improved the nutritional quality of soybean seeds with regard to fats and dietary fiber. They also suggest that specific cultivars should be selected to obtain the desired nutritional features of the soybean raw material depending on its final destination.  相似文献   

12.
To study the incomplete enzymatic extractability of proteins and carbohydrates of thermally treated soybean meals, one unheated and three heat-treated soybean meals were produced. To obtain truly enzyme-resistant material, the meals were extracted by a repeated hydrolysis procedure using excessive concentrations of different combinations of commercial protease and carbohydrase preparations. The water extractability of protein from the different meals varied considerably (13-67%). For all soybean meals, enzymatic treatment extracted most of the original protein (89-94%). Carbohydrase preparations did not improve protein extraction. High-humidity heat treatment led to a more effective enzymatic extraction, which seemed to correlate with the extent of protein denaturation. Results with purified proteins indicated that the soybean meal matrix affects the enzymatic extraction of protein from the meals. Interactions between protein and other components (e.g., cellulose) may explain the incomplete enzymatic extractability of protein from the meals.  相似文献   

13.
Purification and structural characterization of LTP1 polypeptides from beer   总被引:6,自引:0,他引:6  
We report on the purification of lipid transfer proteins (LTP) from barley seeds and beer with the aim of investigating the chemical modifications that occur during the brewing process. In seeds, the well-known LTP of 9 kDa (LTP1) has been found together with a second form named LTPb that displays comparable amino acid composition but was not fully sequenced. These two forms have been recovered in beer with marked chemical modifications including disulfide bond reduction and rearrangement and especially glycation by Maillard reaction. The glycation is heterogeneous with variable amounts of hexose units bound to LTPs. Circular dichroism shows that glycated LTP1 having all their disulfide bridges reduced are totally unfolded. These results provide a first basis for understanding how barley LTPs become foam-promoting agents during the malting and brewing process.  相似文献   

14.
To investigate the effects of light on the accumulation of lipids in seeds, fruits of both peanut and soybean plants were allowed to grow under different types of light conditions (natural, red, blue, green, or far-red light) and in darkness. Irradiation with each type of light from the 20th or 30th day, except for green light from the 30th day, resulted in lower dry weight of peanut seeds. The peanut seeds irradiated with natural, blue or far-red light from the 30th day onward contained a smaller amount of lipids, lower levels of triacylglycerides (TG), and higher levels of total sugar and diacylglycerides (DG), than the seeds grown in darkness. In the case of soybean seeds grown in darkness, the lipid content increased, but the total sugar and protein contents decreased. Exposure of soybean seeds to far-red light did not result in an increase in the lipid content. In vitro, 14C-glycerol-3-phosphate was converted to DG rather than to TG under irradiation with light compared with dark conditions. In contrast, the effect of light on the incorporation of 14C-oleoyl-CoA into TG was not appreciable. These findings suggest that the accumulation of lipid in the seeds of leguminous plants is depressed by light, with far-red light affecting most the accumulation of lipids, which may regulate the synthesis of TG via DG from glycerol-3-phosphate.  相似文献   

15.
Fourier transform infrared (FT-IR) spectroscopy and multivariate analysis were used to identify Pseudomonas aeruginosa and Escherichia coli ATCC 25922 inoculated into bottled drinking water. Three inoculation treatments were examined: (i) E. coli ATCC 25922 (N = 3), (ii) P. aeruginosa (N = 3), and (iii) a 1:1 (v:v) mixed culture of both P. aeruginosa and E. coli ATCC 25922 (N = 3). The control treatment was noninoculated drinking water (N = 3). Second derivative transformation and loadings plots over the range of 1800-900 cm(-1) indicate variations in the following bacterial constituents: amide I band ca. 1650 cm(-1), amide II band ca. 1540 cm(-1), phosphodiester backbone of nucleic acids ca. 1242 and 1080 cm(-1), and polysaccharide compounds ca. 1050-950 cm(-1). Cells with the different treatments were clearly segregated from a mean centered principal component analysis. By using soft independent modeling of class analogy analysis, spectra from a given treatment could be correctly classified 83-88% of the time. These results suggest that FT-IR spectroscopy can determine whether a pure culture is present, in addition to confirming that this method can discriminate between closely related bacteria based on differences in biochemical and phenotypic characteristics that can be detected in this spectral region.  相似文献   

16.
A combination of analytical techniques was used to examine and quantify seed compositional components such as protein, lipid, free sugars, isoflavones, and soyasaponins during soybean development and maturation in two Korean soybean cultivars. Protein accumulation was rapid during reproductive stages, while lipid content was only relatively moderately increased. The major carbohydrate saccarides sucrose and stachyose constantly increased during the reproductive stage. Previously published results suggest that the free sugar and lipid content reached their maximal concentrations at a relatively early stage of seed development and remain constant in comparison to other chemical components. The malonylglucosides were the predominant isoflavone form followed by the glucosides, acetyl glucosides, and aglycone forms. As soybean seed matures, total soyasaponin concentration was constantly decreased until the R8 stage. Soyasaponin beta(g) was the major soyasaponin in DDMP-conjugated group B soyasaponins, followed by the non-DDMP counterpart soyasaponin I and soyasaponin A1. The ratio of total isoflavone to total soyasaponin in the developing soybean increased from 0.06 to 1.31. Protein, lipid, and free sugar contents in the developing soybean seeds showed significant positive correlations with conjugated isoflavones and total isoflavone concentration, while the lipid contents showed a negative correlation with the isoflavone aglycone. Protein, lipid, and free sugar contents showed a negative correlation with total group A and B soyasaponins and total soyasaponins; however, only the soyasaponin A content was significantly negatively correlated with free sugar content. Total soyasaponin content was negatively correlated with isoflavone content (r = -0.828 at p < 0.01).  相似文献   

17.
随着科学技术的发展,低场核磁共振(Low Field Nuclear Magnetic Resonance, LF-NMR)横向弛豫时间(Transverse Relaxation Time, T2)反演谱检测技术越来越多的被应用于农业,但当前对T2反演谱的解译尚停留在水分相态分布层面。为探索从物质成分角度对种子T2反演谱进行解译的新方法,该研究以银杏种子为对象,利用低场核磁共振技术检测并对比银杏鲜种、种子粉末及其主要成分试样的T2反演谱,分析各信号峰的形成机理,并以此为依据对其在种子萌发过程中的变化进行解译。研究结果表明:淀粉与蛋白质混合试样T2反演谱的峰T21、T22、T23以及淀粉与油脂混合试样的峰T24在峰顶时间上和种子粉末试样相对应信号峰完全一致;在物质成分及配比完全相同的情况下,种子粉末试样T2反演谱的峰T21~T24的峰顶时间较鲜种分别相差12.98%、32.21%、13.02%、0%,T21、T22峰比例较鲜种分别偏少41.72%、29.33%,T23峰比例偏多92.26%,T24峰比例偏少91.71%,说明种子组织结构会对其内部水分的弛豫时间和相态分布比例造成一定影响。仅从物质成分角度考虑,种子内水分的弛豫时间主要在淀粉、蛋白质的影响下表现为T21、T22、T23,在淀粉和油脂的影响下表现为T24。由此认为峰T21、T22主要为吸附在淀粉和蛋白质上相态不同的结合水的信号,峰T23为主要被淀粉和蛋白质束缚后产生的半结合水的信号,峰T24主要为种子中自由水的信号(少量源自油脂)。此外,种子即将裂壳时将形成T2a(峰顶时间在10 ms左右)、T2b(峰顶时间>1 000 ms)2个新信号峰,可作为预示种子萌发状态即将发生重要变化的"预兆峰"。提出的从化学组分及核磁检测原理角度对银杏种子萌发过程T2反演谱进行解译的新途径,可为基于LF-NMR方法对种子萌发过程中化学组分变化进行活体分析提供参考。  相似文献   

18.
Low-field NMR T(2) and Fourier transform infrared (FT-IR) measurements were performed on meat samples of two qualities (normal and high ultimate pH) during cooking from 28 degrees C to 81 degrees C. Pronounced changes in both T(2) relaxation data and FT-IR spectroscopic data were observed during cooking, revealing severe changes in the water properties and structural organization of proteins. The FT-IR data revealed major changes in bands in the amide I region (1700-1600 cm(-)(1)), and a tentative assignment of these is discussed. Distributed NMR T(2) relaxation data and FT-IR spectra were compared by partial least-squares regression. This revealed a correlation between the FT-IR peaks reflecting beta-sheet and alpha-helix structures and the NMR relaxation populations reflecting hydration water (T(2B) approximately 0-10 ms), myofibrillar water (T(21) approximately 35-50 ms), and also expelled "bulk" water (T(2) relaxation times >1000 ms). Accordingly, the present study demonstrates that definite structural changes in proteins during cooking of meat are associated with simultaneous alterations in the chemical-physical properties of the water within the meat.  相似文献   

19.
Five different soybean protein sources were added to wheat flour to increase the protein content by 15–25%, and the resulting composite flours were optimally processed into hot‐press tortillas in a pilot plant. The rheological properties of composite flours were evaluated with the farinograph, alveograph, and other wheat quality tests. Tortilla‐making qualities of the control and soybean‐fortified flours were evaluated during dough handling, hot pressing, and baking. The resulting tortillas were tested in terms of yield, physical and chemical parameters, sensory properties, color, and objective and subjective texture. The soybean‐fortified tortillas had increased yields because of the higher dough water absorption and enhanced essential amino acid scores. Among the five different soybean proteins, the defatted soybean flour (SBM1) with the lowest fat absorption index and protein dispersibility index (PDI) and the soybean concentrate produced the best fortified tortillas. The protein meals with high PDI and relatively lower water absorption index (SBM3 and SBM4) produced sticky doughs, lower alveograph P/L values, and defective tortillas. All soybean proteins produced higher yields of tortillas with an enhanced protein quality and amount of dietary fiber.  相似文献   

20.
The aim of present investigation has been to explore the effect of sulfur application on plant metabolism, seed yield and seed quality in soybean. The sulfur was supplied in different doses ranging as 1, 2, 4, 6 and 8 meq S L?1. Plant supplied with 4 meq S L?1 showed optimal growth. Plant growth and dry matter was reduced under sulfur deficiency (1 and 2 meq S L?1) and toxicity (6 and 8 meq S L?1). Application of sulfur increases the tissue sulfur and cysteine concentration in both leaves and seeds. The critical concentration for deficiency (CCD) and toxicity (CCT) of sulfur was observed 0.194 to 0.277% dry weight respectively. Pod yield and seed yield was also suppressed in sulfur deficiency and toxicity. In leaves sugar (reducing, non-reducing and total sugar) and starch was found to be accumulated while in seeds both were depleted under sulfur deficiency and toxicty. Seed storage proteins (albumins, globulins, glutelins and prolamins) were also reduced under sulfur stress. Thus, we conclude that sulfur deficiency and toxicity both affects the plant metabolism, yield and seed quality in terms of carbohydrates and storage proteins of soybean.  相似文献   

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