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1.
Near Infrared Reflectance spectroscopy was tested as a screening method to characterise high lysine mutants from a barley collection by classification through Principal Component Analysis (PCA). Mean spectra of the samples within each cluster identified gene-specific patterns in the 2270–2360 nm region. The characteristic spectral signatures representing the lys5 locus (Risø mutants 13 and 29) were found to be associated with large changes in percentage of starch and (1→3,1→4)-β-glucan. These alleles compensated for a low level of starch (down to 30%) by a high level of (1→3,1→4)-β-glucan (up to 15–20%), thus, maintaining a constant production of polysaccharides at 50–55%, within the range of normal barley.The spectral tool was tested by an independent data set with six mutants with unknown polysaccharide composition. Spectral data from four of these were classified within the high (1→3,1→4)-β-glucan BG lys5 cluster in a PCA. Their high (1→3,1→4)-β-glucan and low starch content was verified. It is concluded that genetic diversity such as from gene regulated polysaccharide and storage protein pathways in the endosperm tissue can be discovered directly from the phenotype by chemometric classification of a spectral library, representing the digitised phenome from a barley gene bank.  相似文献   

2.
The amount of (1 → 3),(1 → 4)-β-d glucan (β-glucan) accumulated in cell walls of barley (Hordeum vulgare L.) kernel is an important determinant for grain end-use. Grain β-glucan concentration is affected by environmental and genetic factors and usually varies from 3 to 6%. In this study, we have analyzed the β-glucan trait in a doubled-haploid (DH) population of 170 lines grown in three separate field trials. Most of the DH lines showed β-glucan values that ranged from that of the low β-glucan parent (cultivar CDC Bold; 3.3%) to that of the high β-glucan parent (breeding line TR251; 5.4%). Eighty-eight lines of the DH population were genotyped using simple sequence repeat (SSR), amplified fragment length polymorphism (AFLP) and diversity array technology (DArT) markers, which were subsequently integrated into a barley genetic map spanning 1059 cM. Interval mapping and multiple-QTL-mapping (MQM) of quantitative trait loci (QTL) from the three trials indicated seven genomic regions associated with low grain β-glucan concentration. For all putative QTLs, the low β-glucan concentration was contributed by alleles from CDC Bold except for two loci on chromosomes 5H that were derived from TR251. A major QTL located to the centromere region of chromosome 7H was identified by both mapping methods for all three trials. The 7H QTL explained up to 39% of the β-glucan concentration and genetic markers associated with the locus may be used to aid selection of high and low β-glucan barley lines.  相似文献   

3.
The acid extract viscosities and β-glucan contents of ten two- and six-rowed barley cultivars grown at seven locations in three consecutive years in Spain were studied in the present work. The viscosities varied from 2·4 to 24·8 centistokes (cSt) and the mean value was 6·4 cSt. The average β-glucan content of barleys determined by HPLC was 3·5% with a range of 1·9–5·5%. Significant differences were found in both β-glucan content and acid extract viscosity between different cultivars, locations and years. The β-glucan contents and viscosities of winter cultivars were higher than those of spring. Cvs. Barbarrosa and Hatif de Grignon were the genotypes with the highest values for both parameters, while cv. Beka had the lowest viscosity and β-glucan content. Environmental factors influenced both parameters. The acid extract viscosities of barleys were correlated negatively with the amount of precipitation (r=−0·754;P<0·05). Barleys grown in wet and rainy areas (Girona and La Coruña) had lower viscosity values.  相似文献   

4.
β-Glucan content and viscosity of water-soluble β-glucans have a considerable impact on the digestion of barley. Eight different 2-row barley (Hordeum vulgare L.) cultivars were grown in controlled environment chambers at five different temperatures until maturity. The samples were pearled, milled and analysed for their content of total, insoluble and soluble β-glucan. The water-soluble fraction was extracted at 37 °C, subjected to amylase treatment and freeze-dried. Water-soluble crude β-glucans were solubilised in distilled water, analysed for viscosity and their purity was checked by nuclear magnetic resonance. Molecular weights were profiled by size exclusion chromatography with RI detection. The content of total β-glucan varied from 4.0% to 7.4%, and was significantly affected by the growth temperature. An interaction between cultivar and growth temperature was observed for the total β-glucan content. The extractability was significantly affected by growth temperature, as there was recorded an increasing amount of water-soluble β-glucan with increasing growth temperature. Both the viscosity and the molecular weight of the water-soluble β-glucans increased with the growth temperature.  相似文献   

5.
Rye crisp doughs and breads were made from three rye flours with different falling numbers (i.e. different enzyme activity), with or without oat bran rich in β-glucan (OBG) added, and with different fermentation times. The aim of the study was to investigate the effect of endogenous enzymes in the flour on molecular weight and content of water-extractable β-glucan in the doughs and breads. The molecular weight distribution of β-glucan was unimodal for the flours, with a calcofluor average molecular weight of about 90×104 g/mol for the rye flours, and 150×104 g/mol for rye flours with added OBG. The molecular weight decreased with increasing fermentation time for all doughs, but was almost unchanged during oven-baking. The calcofluor average molecular weight was highest in doughs and breads made of flour with highest falling number (i.e. lowest enzyme activity), indicating that the endogenous enzymes in the flour were responsible for the breakdown of β-glucan. During fermentation, water-extractable β-glucan was released from the insoluble matrix, probably by the endogenous enzymes in the flour. When the molecular weight of the water-extractable β-glucan decreased, they probably associated with each other or with other components in the dough to form unextractable complexes. The content of water-extractable β-glucan did not change during oven-baking.  相似文献   

6.
Bread-making with a composite flour (CF) consisting of 60% wheat flour (WF) and 40% hull-less barley flour, increased the total and soluble (1→3,1→4)-β-D-glucan and total arabinoxylan (AX) contents of dough and bread samples, but decreased the specific bread loaf volume. A xylanase insensitive to inhibition by Triticum aestivum L. xylanase inhibitor (TAXI) and xylanase inhibiting protein (XIP), increased loaf volume by 8.8 and 20.1% for WF and CF breads, respectively. Xylanase addition not only markedly improved loaf volume of CF bread, but also increased the soluble AX content of the WF and CF dough and bread samples because of conversion of water-unextractable AX into soluble AX. The xylanase had no impact on the extractability and molecular weight of (1→3,1→4)-β-D-glucan, but (1→3,1→4)-β-D-glucan was degraded during bread-making probably because of endogenous β-glucanase activity. Taken together, the results clearly show that the combined use of hull-less barley flour and a xylanase active during bread making, lead to palatable breads with high total and soluble AX and (1→3,1→4)-β-D-glucan contents. The sum of total AX and (1→3,1→4)-β-D-glucan was 1.70% for WF bread and 3.06% for CF bread, while the sum of soluble AX and (1→3,1→4)-β-D-glucan was 0.49 and 1.41% for control WF and CF xylanase supplemented breads, respectively.  相似文献   

7.
The fatty acid profiles and tocopherol and phytosterol contents of crude oils of cress (Lepidium sativum L.) and field pennycress (Thlaspi arvense L.) are reported, along with yields from the corresponding seeds. The physical properties of these oils were also determined, which included oxidative stability, kinematic viscosity, viscosity index, low temperature fluidity, specific gravity, acid value, lubricity, and iodine value. The oil content of dried cress and field pennycress seeds was 22.7 and 29.0 wt%, respectively. The primary fatty acids found in cress oil were oleic (30.6 wt%) and linolenic acids (29.3 wt%), whereas field pennycress oil was principally composed of erucic (32.8 wt%) and linoleic (22.4 wt%) acids. Cress oil contained high concentrations of γ- (1422 ppm) and δ- (356 ppm) tocopherols, whereas α-tocopherol (714 ppm) was the primary tocopherol discovered in field pennycress oil. The overall tocopherol concentrations of cress and field pennycress oils were 1799 and 851 ppm, respectively. The primary phytosterols elucidated in cress and field pennycress oils were sitosterol and campesterol, with avenasterol also present in significant quantity in cress oil. The total phytosterol concentration in cress oil (14.41 mg/g) was greater than that in field pennycress (8.55 mg/g) oil. Field pennycress oil exhibited excellent low temperature fluidity, whereas cress oil was more stable to oxidation and over a range of temperatures displayed lower kinematic viscosities as well as a higher viscosity index. The acid and iodine values of field pennycress oil were lower than those for cress oil, but both oils had excellent lubrication properties.  相似文献   

8.
Eight field experiments were conducted at four sites in the UK in 2003 and 2004 to investigate the effects of sulphur (S) application on yield and malting quality of barley. Significant yield responses to S additions were obtained in five out of the eight experiments, with yield increases ranging from 0.2 to 1.2 t/ha (4.7–22.5%). At the two most S-deficient sites, S application significantly increased malt diastatic power, alpha-amylase activity, friability and homogeneity, and decreased (1→3,1→4)-β-glucan concentration in the wort, indicating an improved endosperm modification during malting. Sulphur applications also significantly increased the concentration of S-methylmethionine (the precursor of dimethylsulphide) in kilned malt, which could impact on beer flavour. When the supply of N was limiting, S applications decreased grain N concentration due to a dilution effect as a result of increased grain yield. In some cases, S applications resulted in decreased grain size. At sites non-deficient or marginally deficient in S, applications of S had little effect on grain or malting quality parameters. The need to maintain an adequate S supply to barley for both yield and malting quality was demonstrated.  相似文献   

9.
The essential oils obtained by hydrodistillation from the aerial parts of Tunisian native Hypericum perfoliatum L. (sect. Drosocarpium Spach.) and Hypericum tomentosum (sect. Adenosepalum Spach.) were analyzed by GC and GC–MS. Thirty-two compounds were identified in the essential oils of H. perfoliatum with α-pinene (13.1%), allo-aromadendrene (11.4%), germacrene-D (10.6%), n-octane (7.3%), α-selinene (6.5%) and β-selinene (5.5%) as main constituents. Sixty-seven components were identified in the oil of H. tomentosum with menthone (17.0%), n-octane (9.9%), β-caryophyllene (5.3%), α-pinene (5.2%), lauric acid (4.1%) and β-pinene (3.7%) as the most abundant components. Both oils were characterized by the presence of many components which could have numerous applications in food, pharmaceutical and perfume industries.  相似文献   

10.
Various populations of hemicellulosic material were solubilised from water-unextractable cell wall material (WUS) of sorghum (Sorghum vulgarecv. Fara Fara) by sequential extractions with alkali. Saturated Ba(OH)2-solutions, followed by distilled water, 1 KOH, 4 KOH and 4 KOH containing 4% (w/v) H3BO3 were used to extract primarily glucuronoarabinoxylans (GAX) from sorghum WUS. Cellulose remained in the residue. In total over 90% of all GAX originally present in the WUS were recovered, particularly in the saturated Ba(OH)2, 1 KOH and 4 KOH extracts. Saturated Ba(OH)2 was found to be the most selective of the extractants tested for GAX. (1→3), (1→4)-β- -glucans were found predominantly in the fraction obtained by washing with water after the extraction with saturated Ba(OH)2. All extracted arabinoxylans were highly substituted (arabinose/xylose>1) and contained, besides -arabinose and -xylose, the acidic sugars -glucuronic, 4-O-methyl- -glucuronic and -galacturonic acid. The average molecular weight ranged from 210 000–1 300 000, which corresponds with DPs ofc. 1500 to 9300. The selectivity of the extractant was apparently enhanced by the presence of a bivalent cation.  相似文献   

11.
Near infrared spectroscopic (NIR; 1100–2500 nm), chemical and genetic data were combined to study the pleiotropic secondary effects of mutant genes on milled samples in a barley seed model. NIR and chemical data were both effective in classifying gene and gene combinations by Principal Component Analysis (PCA). Risø mutants R-13, R-29 high (1→3, 1→4)-β-glucan, low starch and R-1508 (high lysine, reduced starch), near isogeneic controls and normal lines and recombinants were studied. Based on proteome analysis results, six anti-microbial proteins were followed during endosperm development revealing pleiotropic gene effects in expression timing that supporting the gene classification. To verify that NIR spectroscopy data represents a physio–chemical fingerprint of the barley seed, physical and chemical spectral components were partially separated by Multiple Scatter Correction and their genetic classification ability verified. Wavelength bands with known water binding and (1→3, 1→4)-β-glucan assignments were successfully predicted by partial least squares regression giving insight into how NIR-data works in classification. Highly reproducible gene-specific, covariate, pleiotropic classification patterns from NIR and chemical data were demonstrated in PCAs and by visual inspection of NIR spectra. Thus PCA classification of NIR-data gives the classical genetic concept, ‘pleiotropy’, a new operational definition as a fingerprint from a spectroscopic representation of the phenome carrying genetic, physical and chemical information. It is concluded that barley seed phenotyping by NIR and chemometrics is a new, reliable tool for characterising the pleiotropic effects of mutant gene combinations and other genotypes in selecting barley for quality in plant breeding.  相似文献   

12.
Using a PCR-based strategy, four new 75K γ-secalin genes were isolated from Secale cereale, Secale vavilovii, Secale sylvestre, and Secale strictum in genus Secale (rye). Based on amino acid sequences, the primary structure of the 75K γ-secalin subunits was demonstrated, which was composed of four main structural regions: (a) a conservative 19 amino acids signal peptide, (b) a steady short N-terminal region of 12 amino acids containing a cysteine residue, (c) a repetitive domain, which began with the conservative tetrapeptides PQ3 and was rich in glutamine and proline. PFPQ1−2(PQQ)1−2 was the core repeat motif in the repetitive region. Besides amino acid substitutions, this region showed variations in length due to the insertion and deletion events. In the repetitive region of EF432549 (Secale strictum), there were two octapeptides (PFPQQPQQ and PVPQQSQQ) insertions. On the contrary, deletion events of two residues (QT) took place in EF432546 (Secale sylvestre). Accounting for the amino acid replacement, an extra cysteine residue appeared in the repetitive region of EF432546, which did not exist in other genes, and (d) a conserved 143 amino acids C-terminal domain including eight cysteine residues. The implications of the results for quality improvement are discussed.  相似文献   

13.
Dried flowers and leaves of four different Achillea species grown wild in several provinces of Iran, including one species collected from three different locations of Isfahan province were analyzed for the headspace volatile components, total phenolics (TP) and tartaric esters (TE). Capillary gas chromatography/mass spectrometry (GC/MS) combined with a purge and trap method was used for quantification of aroma components. Over 70 compounds were determined in the samples. Flower samples from all species contained 2-methyl butanal, α-pinene, α-thujene, camphene, hexanal, β-pinene and 1,8-cineole; however, the major constituents of the aerial parts were determined as α-pinene, camphene, DL-limonene and 1,8-cineole. The largest number of aroma components were found in Achillea tenuifolia Lam. and Achillea millefolium L. In all species, except A. millefolium, the leaves contained more TP and TE than flowers. However, A. wilhelmsii from Semirom in Isfahan province showed the highest values for TP and TE.  相似文献   

14.
Barley alpha-amylase isozymes 1 (AMY1) and 2 (AMY2) have 80% sequence identity but possess different physico-chemical properties. By incubation in the range 37–85 °C T50 is 75.2 °C of AMY1 and 79.2 °C of AMY2. While AMY2 is also most stable in urea at pH 6.7, [urea]50 being 8.2 M compared to 7.9 M for AMY1, AMY1 has highest stability in urea below pH 6 or in the presence of NaCl. Moreover AMY1 is most stable in guanidinium chloride. Charge screening thus destabilises AMY2 but stabilises AMY1. Isozyme sequence comparison suggests that AMY1 lacks four of the 20 salt-bridges identified in the crystal structure of AMY2. The four residues that differ comprise Lys67AMY2 and Asp267AMY2, forming salt-bridges on the surface of the catalytic (β/α)8-barrel (domain A), and Glu96AMY2 and His344AMY2 that participate in charged networks between domain A and the small domain B and the C-terminal domain, respectively. Four corresponding AMY2 mimics A68K; D97E; Q269D; N346H were made in AMY1 by site-directed mutagenesis. While D97E and Q269D have slightly improved stability compared to AMY1 wild-type, N346H and, under certain conditions, A68K are destabilised. The four mutants show 22–176% activity (kcat/Km) toward 2-chloro-4-nitrophenol β- -maltoheptaoside and amylose DP17 and 43–117% activity for insoluble starch.  相似文献   

15.
Grain characteristics and groat composition have been evaluated in 35 genotypes from nine taxonomic species of Avena, including three species (A. agadiriana, A. atlantica, A. damascena) for which no previous data are available. There was substantial interspecific and intraspecific variation for all characteristics measured. The proportion of groat in the grain ranged from 32·7–62·1%, and mean groat weight from 2·4–37·4 mg. Groat protein concentrations ranged from 13·9–41·3%, and exceeded 32% in one A. atlantica, two A. damascena and one A. murphyi genotype. Groat β-glucan concentration showed very wide variation (2·2–11·3%) are there were substantial interspecific and intraspecific differences. The highest β-glucan concentrations were found in genotypes of A. atlantica. Although there were interspecific and intraspecific variations in groat oil concentration (4·2–10·6%), and in fatty acid composition, data were within previously reported ranges for A. sativa. Overall these data indicate that some of the genotypes of the wild species studied may be of value for breeding oats with improved levels of β-glucan and protein, and that further studies are warranted into both interspecific and intraspecific variations in grain quality factors in wild oat species.  相似文献   

16.
Three different fucoidan fractions were isolated and purified from the brown alga, Sargassum mcclurei. The SmF1 and SmF2 fucoidans are sulfated heteropolysaccharides that contain fucose, galactose, mannose, xylose and glucose. The SmF3 fucoidan is highly sulfated (35%) galactofucan, and the main chain of the polysaccharide contains a →3)-α-l-Fucp(2,4SO3)-(1→3)-α-l-Fucp(2,4SO3)-(1→ motif with 1,4-linked 3-sulfated α-l-Fucp inserts and 6-linked galactose on reducing end. Possible branching points include the 1,2,6- or 1,3,6-linked galactose and/or 1,3,4-linked fucose residues that could be glycosylated with terminal β-d-Galp residues or chains of alternating sulfated 1,3-linked α-l-Fucp and 1,4-linked β-d-Galp residues, which have been identified in galactofucans for the first time. Both α-l-Fucp and β-d-Galp residues are sulfated at C-2 and/or C-4 (and some C-6 of β-d-Galp) and potentially the C-3 of terminal β-d-Galp, 1,4-linked β-d-Galp and 1,4-linked α-l-Fucp residues. All fucoidans fractions were less cytotoxic and displayed colony formation inhibition in colon cancer DLD-1 cells. Therefore, these fucoidan fractions are potential antitumor agents.  相似文献   

17.
The chemical composition of essential oils isolated from aerial parts of native populations of Origanum vulgare L. from northwestern Himalaya was investigated by enantioselective gas chromatography (enantio-GC), capillary-gas chromatography (capillary-GC) and GC–MS. Seventy compounds, which accounted for 84.9–97% of the oil composition, have been identified. The oils were allotted to two main groups; the first group had a high percentage of components belonging to the thymol/carvacrol biosynthetic pathway and the second was characterized by a different sesquiterpene composition and a high linalool and bornyl acetate percentage. Essential oils of O. vulgare populations from Rilkot and Dhanachuli areas in northwestern Himalaya were characterized by high monoterpenoids proportions as compared to Nainital and Bhowali populations, which were dominated by sesquiterpenoids. High proportions of thymol (29.2–82%) were found only in two populations. Composition of the samples collected from Dhanachuli area differed from Nainital and Bhowali collections by a unique presence of carvacrol. Notably, there were significant differences in the concentration of rest of the terpenes in all the collections. On enantio-GC, enantiomeric excess for (3R) (−)- and (3S) (+)-linalool, (S) (+)- and (R) (−)-terpinen-4-ol, (S) (−)- and (R) (+)-α-terpineol, (1S) (−)-bornyl acetate and (1S) (−)-borneol were established in populations from Bhowali and Dhanachuli area. Moreover, linalool type oregano may be useful in promoting wider commercial utilization of the biodiversity of this species.  相似文献   

18.
The relative abundance of isoprenoids and other volatile components in the aerial parts of Artemisia annua Linn. (Asteraceae) after different nutritional treatments was analyzed by GC and GC/MS. Hydro-distillation of untreated (control) plants yielded 0.28 ± 0.04% essential oil on fresh weight basis. Monoterpenes were predominant in the essential oil of which cis-limonene-1,2-epoxide (22.1%), artemisia ketone (11.5%), iso-pinocamphone (11.4%), thujyl alcohol (9.9%) and camphor (8.4%) were the major components. The essential oil distilled from A. annua treated with Azospirillum (2 ml/plant) amounted to 0.30 ± 0.03% of fresh weight and consisted mainly of neral (31.1%), β-caryophyllene (25.1%), artemisia ketone (10.0%), thujyl alcohol (9.4%), trans-bergamotene (8.5%) and spathulenol (4.8%). The essential oil from plants treated with basal N, P, K and S application (in the form of urea P2O5, K2O and gypsum at a rate of 120, 50, 100 and 50 kg/ha, respectively) amounted to 0.32 ± 0.03% of fresh weight and consisted mainly of thujyl alcohol (33.3%), β-caryophyllene (15.5%), cis-undec-5-ene (14.4%), artemisia ketone (6.0%), trans-nerolidol (5.8%) and undec-4-ene (4.6%). The hydrodistillation of A. annua treated with Glomus (Mycorrhizal soil 50 g/plant) yielded 0.50 ± 0.02% essential oil on fresh weight basis. The sesquiterpenes were predominant in this essential oil and consisted of β-caryophyllene (51.2%), trans-bergamotene (15.4%), α-gurjunene (14.3%), germacrene D (5.1%) and ledol (4.5%) as major components. The only monoterpenes in the essential oil were neral, nerol and pulegone (each less than 1%). These findings suggest that A. annua treated with Glomus lacks glandular trichomes—the primary sites of synthesis of monoterpenes.  相似文献   

19.
Associations between RVA pasting properties and three single nucleotide polymorphism (SNP) sites in the Waxy gene intron 1, exon 6, and exon 10 were determined using rice genotypes of diverse geographic origin. A total of four SNP-haplotypes (combination of SNP alleles) were identified that explained high proportions of the variation in RVA pasting properties (R2 = 0.574–0.704). A haplotype containing DNA sequence variation in exon 10 (exon 10 cytosine nucleotide) was exclusively found in high-apparent amylose content (AAC) genotypes with a higher RVA viscosity profile compared to the high AAC genotypes with a different haplotype. The exon 10 SNP explained variances in coolpaste and setback (coolpaste–hotpaste) to 0.642 and 0.499, respectively. Across three haplotypes, which contained exon 10 adenine nucleotide, AAC was correlated with peak, hotpaste, breakdown and setback (coolpaste–hotpaste) at r = −0.85, −0.75, −0.79, and 0.49, respectively. Therefore, the exon 10 SNP differentiates high AAC types with a strong RVA profile and thus can be used by molecular breeding programs focused on quality improvement. Additionally, characterizing genotypes by their functional SNPs allowed us to better understand the relationship between the Waxy gene, its chemical product (i.e., AAC) and the functionality created by the product (i.e., pasting properties).  相似文献   

20.
Two new 9,11-secosteroids, 22α-acetoxy-24-methylene-3β,6α,11-trihydroxy-9,11-seco-cholest-7-en-9-one (1) and 11-acetoxy-24-methylene-1β,3β,6α-trihydroxy-9,11-seco-cholest-7-en-9-one (2), as well as two known norcembranoids, 5-epi-sinuleptolide (3) and sinuleptolide (4), were isolated from the soft coral Sinularia nanolobata. The structures of these metabolites were elucidated on the basis of extensive spectroscopic analysis. The anti-HCMV (human cytomegalovirus) activity of 1–4 and its cytotoxicity against selected cell lines were evaluated.  相似文献   

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