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Starch was isolated from four new waxy barleys and compared with normal and high‐amylose barley starch. The waxy barley samples were selected lines from crosses of Swedish hulled and naked barley cultivars with the cultivar Azhul as donor of the waxy gene. The starches from the waxy barley samples were found to contain 0.7–2.6% amylose when determined iodimetrically by amperometric titration and 0.0–0.9% when determined by size exclusion chromatography after debranching. However, Sepharose CL‐2B elution profiles of the starches detected by iodine staining showed that all four waxy samples were free from detectable amounts of amylose. The amylopectin starches were found to contain a small polysaccharide fraction with molecular size smaller than amylopectin, with an iodine staining λmax range of 550–600 nm. The water extractable and acid extractable β‐glucan contents in the waxy barley cultivars were generally found to be higher than those in normal barley. 相似文献
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This paper describes initial experiments carried out in a collaborative study with Perten Instruments, Sweden, using Near‐Infrared spectroscopy to assess β‐glucan content in single grains of barley and malt. In general, the method needs further development, but this study shows that it has potential as a valuable tool for assessing endosperm modification of malt. The method is fast and non‐destructive and therefore allows other parameters related to endosperm modification to be analysed using the same grains. 相似文献
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Neha M. Sahasrabudhe Jelleke Dokter‐Fokkens Paul de Vos 《Molecular nutrition & food research》2016,60(11):2514-2522
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Pirkko Kuusela Jari J. Hmlinen Pekka Reinikainen Juhani Olkku 《Journal of the Institute of Brewing》2004,110(4):309-319
A dynamic model was developed that describes the formation of β‐glucanase and the degradation of β‐glucans at different temperatures and grain moistures during the germination of malting barley. The process was analysed by simulations and by solving an optimal control problem for maximising the β‐glucanase activity. The results demonstrate the effects of controlling dynamically the germination process and improve the understanding of cytolysis in germination. 相似文献
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Junzhou Ding Yufang Wang Shanbai Xiong Siming Zhao Qilin Huang 《International Journal of Food Science & Technology》2013,48(2):253-259
With a view to utilise yeast (1→3)‐β‐d ‐glucan as biological response modifiers with better water solubility, carboxymethylation was carried out by a two‐step alkalisation and etherification with monochloroacetic acid. Four technological parameters of carboxymethylation were investigated by orthogonal experiments for obtaining the maximum degree of substitution (DS), apparent viscosity (η) and solubility of carboxymethyl derivatives. In view of the orthogonal analysis, the optimal technological parameters were reaction temperature 50 °C, total reaction time 5 h, 3 mL of 50% sodium hydroxide as the second alkali dosage and 15 mL of 4 m chloroacetic acid. In addition, it was found that ball milling pretreatment for original (1→3)‐β‐d ‐glucan can be an advantage for carboxymethylation. By contrast, DS, η and solubility of carboxymethyl product increased 24%, 6% and 22%, respectively, suggesting the effect of ball milling pretreatment could not be neglected on improvement of DS, η and solubility for carboxymethyl products. 相似文献
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Roser Vila Marisa Mundina Felix Tomi Jos F. Cicci Mahabir P. Gupta Jos Iglesias Joseph Casanova Salvador Caigueral 《Flavour and Fragrance Journal》2003,18(3):198-201
Essential oils obtained by hydrodistillation from the leaves and flower spikes of Piper friedrichsthalii from Costa Rica and Panama, and leaves of P. pseudolindenii from Costa Rica were analysed by GC–FID, GC–MS and 13C‐NMR. Monoterpenoids constituted the main fraction of the oils of P. friedrichsthalii from Costa Rica, particularly α‐pinene, camphene, β‐phellandrene, limonene and menthane derivatives, whereas the oils from leaves of P. friedrichsthalii from Panamá and of P. pseudolindenii from Costa Rica were characterized by a high sesquiterpene content, especially 11‐selinen‐4α‐ol, α‐selinene, germacrene D and β‐selinene in the former, and β‐elemene, β‐caryophyllene, germacrene D and α‐humulene in the latter. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Khaled El‐Zahar Mahmoud Sitohy Michle Dalgalarrondo Yvan Choiset Franois Mtro Thomas Haertl Jean‐Marc Chobert 《Molecular nutrition & food research》2004,48(3):177-183
Ovine whey proteins were fractionated and studied by using different analytical techniques. Anion‐exchange chromatography and reversed‐phase high‐performance liquid chromatography (HPLC) showed the presence of two fractions of β‐lactoglobulin but only one of α‐lactalbumin. Gel permeation and sodium dodecyl sulfate (SDS)‐polyacrylamide gel electrophoresis allowed the calculation of the apparent molecular mass of each component, while HPLC coupled to electrospray ionisation‐mass spectrometry (ESI‐MS) technique, giving the exact molecular masses, demonstrated the presence of two variants A and B of ovine β‐lactoglobulin. Amino acid compositions of the two variants of β‐lactoglobulin differed only in their His and Tyr contents. Circular dichroism spectroscopy profiles showed pH conformation changes of each component. The thermograms of the different whey protein components showed a higher heat resistance of β‐lactoglobulin A compared to β‐lactoglobulin B at pH 2, and indicated high instability of ovine α‐lactalbumin at this pH. 相似文献
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V. K. Raina R. K. Lal Savita Tripathi M. Khan K. V. Syamasundar S. K. Srivastava 《Flavour and Fragrance Journal》2002,17(2):144-146
An Erratum for this article has been published in Flavour and Fragrance Journal 17(5) 2002, 404. The essential oil composition of four genetically diverse stocks of Murraya koenigii leaves cultivated at the CIMAP Research Farm, Lucknow, were analysed by GC and GC–MS. The oil from the stock of the northern Indian plains, Lucknow, showed β‐pinene (70.0%), β‐caryophyllene (6.5%) and α‐pinene (5.4%) as the major constituents, while the oil from the stock of the lower Himalayan range, Pant Nagar, showed α‐pinene (65.7%), β‐pinene (13.4%) and β‐phellandrene (7.4%) as the major constituents. In contrast to the above, the oil from the stock of southern India, Kozhikode, showed β‐caryophyllene (53.9%), aromadendrene (10.7%) and α‐selinene (6.3%) as the major constituents. On the other hand, the oil from the stock of eastern India, Bhubaneshwar, showed β‐phellandrene (30.2%), β‐caryophyllene (24.2%), α‐pinene (15.0%), (E)‐β‐ocimene (5.0%) and aromadendrene (4.5%) as the major constituents. The GC–MS analysis of the stock oil samples from the northern Indian plains, lower Himalayan range, southern and eastern India resulted in the identification of 65, 56, 57 and 66, constituents, representing 99.2%, 98.8%, 87.4% and 98.2% of the oils, respectively. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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The essential oil of Nepeta racemosa (Lamiaceae) was prepared by hydrodistillation and was analysed by a combination of GC and GC–MS. Twenty‐four components were identified, constituting approximately 99.3% of the oil. The major constituents of essential oil were 4aβ,7α,7aβ‐nepetalactone (33.6%), 4aα,7α,7aβ‐nepetalactone (25.6%), 4aα,7α,7aα‐nepetalactone (24.4%) and 1,8‐cineole (9%). Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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J.E. Georg‐Kraemer E. Caiero E. Minella J.F. Barbosa‐Neto S.S. Cavalli 《Journal of the Institute of Brewing》2004,110(4):303-308
Eighteen barley genotypes used in Brazilian malting barley breeding programs were characterized in relation to (1–3, 1–4)‐β‐glucanase activity in green and kilned malt. They were tested to determine the loss of enzyme activity during kilning in the malting process and the environmental effects on enzyme activity were measured. The genotypes analyzed showed great variation regarding the enzyme activity in both kinds of malt, in a range from 531.94 to 934.31 U/kg in green malt, and from 187.02 to 518.40 U/kg in dry malt. The mean enzyme activity loss during kilning was close to 60%, very similar to the results obtained in other studies. The loss among genotypes varied from 8.04% to 71.54%. The enzyme activity varied significantly under the different environments tested, showing existence of environmental effects on the genotypes analyzed. Embrapa 127 was the genotype that exhibited the highest enzyme activity in finished malt although it had shown a low activity in green malt, reflecting a negligible loss of activity during kilning. The data indicate promising results to malting barley breeding due to the wide variability exhibited by genotypes as to enzyme activity and levels of isoenzyme with high thermostability. 相似文献
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Jesús Pal‐Paúl M. Jos Prez‐Alonso Arturo Velasco‐Negueruela M. Teresa Ballesteros Jesús Sanz 《Flavour and Fragrance Journal》2006,21(3):410-415
The essential oil from the aerial parts of Sideritis hirsuta L. gathered in Guadalajara Province, Spain, has been extracted by steam distillation and analysed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC–MS). A total of 73 compounds have been identified, monoterpene compounds being the most important. The principal constituents have been identified as β‐phellandrene (23.8%), α‐phellandrene (9.2%), α‐pinene (8.2%) and (Z)‐β‐guaiene (8.1%). Although the chemical composition of the essential oil of this species from other provinces is similar, 44 of the 73 identified compounds have not been previously reported in this species. It is the first time that the sesquiterpene (Z)‐β‐guaiene (8.1%) has been detected and mentioned as a major constituent in this species, therefore it could be considered to describe a new chemotype for Sideritis hirsuta L. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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L. F. De Buyck H. L. De Pooter N. M. Schamp R De Bruyn Weiguo Zhang M. Bud &#x;ínský O. Motl 《Flavour and Fragrance Journal》1989,4(2):53-57
The structure of the new sesquiterpene alcohol β-copaen-4α-ol, isolated as a major constituent of the volatile fraction of Otacanthus coeruleus Lindl., was assigned using NMR information. The otherwise difficult discrimination between copaene and ylangene structures can be made unambiguously by a 13C-NMR criterion. All 13C-chemical shifts of the carbon atoms in copaene-ylangene pairs are nearly superimposable, except for those of C-2 and C-6 which show striking differences (11 ppm). These differences are rationalized by invoking sterically induced shifts caused by 1,4-'flagpole'-interactions between the hydrogen atoms on C-6 and C-9 (for copaenes) or on C-2 and C-9 (for ylangenes) in boatlike conformations. In the 1H-NMR spectra, the chemical shift of the ‘compressed’ hydrogen atoms H-6 (in the copaene) and H-2 (in the ylangene) shows a 0.5 ppm downfield shift in comparison with the chemical shift of the unhindered ones (H-2 in the copaene and H-6 in the ylangene). 相似文献
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Bo Liu Tao Yang Linna Zeng Limin Shi Yan Li Zanguo Xia Xuping Xia Qinlu Lin Feijun Luo 《International Journal of Food Science & Technology》2016,51(12):2574-2582
Inflammatory bowel disease (IBD) is highly prevalent worldwide and includes ulcerative colitis (UC) and Crohn's disease. It is a high incidence rate disease all over the world and an inducement of colon cancer. The aim of this study was to investigate the potential protective effect of Fuzhuan brick tea (FBT) against colitis induced by dextran sulphate sodium (DSS) in mice. ICR mice were administered FBT orally for 7 days before drinking 3% DSS (w/v). The FBT significantly attenuated the symptoms of colitis including diarrhoea, rectal bleeding and loss of body weight. FBT reduced the shortening of colon length and alleviated the histopathological damages. The myeloperoxidase activity, nitric oxide and malondialdehyde level in colon tissues were also significantly decreased by FBT. Besides, FBT treatment obviously suppressed the expression of the inflammatory cytokines such as TNF‐α, IL‐1β and IFN‐γ. Our results provide a safe and efficient method for preventing and treating colitis. 相似文献
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Alessandra Bertoli Francesco Menichini Cecilia Noccioli Ivano Morelli Luisa Pistelli 《Flavour and Fragrance Journal》2004,19(2):166-171
The essential oil and SPME samples of the leaves, flowers and seeds of Psoralea bituminosa L. were analysed by GC and GC–MS. We have investigated also the presence of monoterpene or aliphatic alcohol glucosides. The essential oils showed both qualitative and quantitative differences. The main constituents of the leaf and the flower essential oils were caryophyllene (23% and 18%, respectively), β‐farnesene (15% and 6%, respectively), and germacrene D (24% and 18%, respectively). Significant amounts (7%) of the same compounds were also directed in the seed essential oil, but tricyclene (11%) and α‐pinene (50%) were the most important constituents of this oil. The volatile fractions of remaining leaf aqueous extracts after treatment with β‐glucosidase revealed qualitative differences in comparison with the composition of the corresponding essential oils, and high levels of 3‐hexen‐1‐ol (37%) and 1‐octen‐3‐ol (27%) were observed. The SPME analysis of the fresh leaves, flowers and seeds of P. bituminosa confirmed the qualitative composition of the volatile oils, even if we detected significative differences in the percentage ratio between monoterpenes and sesquiterpenes in comparison with the oils, where sesquiterpenes were the main components. In fact the variation of the monoterpenes, tricyclene, α‐pinene and camphene between the leaf oil and the corresponding headspace sample was remarkable: tricyclene increased from 0.1% to 8%, α‐pinene from 0.1% to 16% and camphene from 0.3% to 10% in the SPME samples. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献