Preliminary Study of Fat Oxidation in Sorghum and Maize Brewing

Superoxide dismutase (SOD) activity in the white sorghum farafara and ICRISAT sorghum variety – ICSV 400 was at a high activity in the embryo at about 8 SOD units/tissue. This activity was almost completely destroyed at 80 °C. Totox index of the brewing grains were 366 for ICSV 400, 312 for farafara, 112 for maize grits and 90 for barley malt. Worts from sorghum/maize and sorghum/barley malt brews all had hydroperoxy linoleic acid (15–19 μM) which remained undetected after wort boiling. Sorghum/maize brews formed very little trub (wort proteinous sediments) in the whirlpool and trub increased in sorghum/barley brews with increased usage of barley malt. Sorghum/maize brews had free fatty acids (FFA) at 22 mg/l in pitching wort but in sorghum/barley brew (50/50) only 9 mg/l. This revised version was published online in July 2006 with corrections to the Cover Date.     

Phloem Transport of Amino Acids in Relation to their Cytosolic Levels in Barley Leaves

A comparison of barley (Hordeum vulgare L.) leaves was made between the cytosolic content of amino acids and sucrose as determined by subcellular fractionation and the corresponding concentration in phloem sap, which was collected continuously for up to 6 days from severed aphid stylets. Because amino acids were found to be almost absent from the vacuoles, and because the amino acid patterns in the stroma and cytosol are similar, whole leaf contents could be taken as a measure of cytosolic amino acid levels for a comparison of data during a diurnal cycle. The results show that the pattern of amino acids in the phloem sap was very similar to the pattern in the cytosol. Therefore, we concluded that the overall process of transfer of amino acids from the cytosol of the source cells into the sieve tubes, although carrier mediated, may be a passive process and that the translocation of amino acids via the sieve tubes requires the mass flow of sucrose driven by the active sucrose transport involved by the phloem loading.     

Modulation of Calmodulin mRNA and Protein Levels in Barley Aleurone

Changes in calmodulin (CaM) mRNA and protein were investigated in aleurone layers of barley (Hordeum vulgare L. cv Himalaya) incubated in the presence and absence of calcium, gibberellic acid (GA3), and abscisic acid (ABA). CaM mRNA levels increased rapidly and transiently following incubation of aleurone layers in H2O, CaCl2, or GA3. The increase in CaM mRNA was prevented by ABA. This increase in CaM mRNA was brought about by physical stimulation during removal of the starchy endosperm from the aleurone layer. CaM protein levels did not increase in response to physical stimulation. Only incubation in GA3 plus CaCl2 brought about a rapid increase in CaM protein levels in the aleurone cell. ABA reduced the level of CaM protein below that found at the beginning of the incubation period. The rise in CaM protein preceded increases in the synthesis and secretion of [alpha]-amylase. Immunocytochemistry with monoclonal antibodies to carrot and mung bean CaM was used to localize CaM in aleurone protoplasts. Monoclonal antibodies to tubulin and polyclonal antibodies to tonoplast intrinsic protein and malate synthase were used as controls. CaM was localized to the nucleus, the vacuolar membrane, and the cytosol, but was not associated with microtubules.     

Cation Effects on Chloride Fluxes and Accumulation Levels in Barley Roots

Accumulation of Cl^- by excised barley roots, as of K⁺, approaches a maximum level at which the ion influx and efflux rates become equal. The rate of Cl^- influx at this equilibrium is close to the initial rate while the efflux rate increases with time from zero to equality with influx. The Cl^- fluxes are independent of simultaneous exchange flux of the cations, but depend on the nature and concentration of the salt solutions from which they originate. The Cl^- content at equilibrium, however, is largely independent of the external concentrations. The approach to equilibrium reflects the presence of the cation. Cl^- flux equilibrium is attained more rapidly in KCl than in CsCl or CaCl₂. This is presumably an effect of much slower distribution of Cs⁺ and Ca⁺⁺ than of K⁺ within the roots. Accumulated Cs⁺ appears to form a barrier to ion movement primarily within the outermost cells, thereby reducing influx and ultimately efflux rates of both Cl^- and cations. Slow internal mixing and considerable self-exchange of the incoming ions suggest internal transport over a series of steps which can become rate-limiting to the accumulation of ions in roots.     

大麦花药培养中海藻酸钠作用的初步探讨

本试验以普通大麦（Hordeum vulgare L.）品种单核晚期的花药为材料,研究了他们在液体培养过程中海藻酸钠的作用。结果表明：在供试的4个海藻酸钠浓度（1、2、3、6%）中,以浓度为2-3%的效果最佳。当他们代替20-30%的Ficoll时,无论是用BAC3培养基,还是用MS培养基,培养基中加NAA,还是家2,4-D,都能诱导出愈伤组织,但以每升培养基加2mg NAA和1 mg 6-BA的效果最佳,在含这种激素的培养基上,一些基因型的出愈率相当高,供试基因型都在100%以上,而且有些花粉粒能直接发育成能正常发芽出苗的胚状体。Barley anthers at the late uninucleate stage were cultured in order to study the use of sodium alginate in liquidmedium.The results showed that, the effect of 2-3% (W/V) sodium alginate was best in 4 concentration studied (1%,2%,3%and 6%). When the 2-3% sodium alginate was substituted for 20-30% ficoll, the calli could be induced from anthers of all genotypes whether on BAC3 medium or MS medium and whether adding NAA or 2,4-Din medium.2mg/L NAA+1mg/L 6-BA added to medium could give better results and on the medium with these hormones the callus rate of all genotypes were above 100%. Some pollens could grow into embryoids directly.     

诱导突变高粱愈伤组织初探

本实验以突变体高粱的不同外植体 ,成熟种子、成熟胚、茎尖、和幼胚等为材料 ,诱导愈伤组织。经出愈率和生长状况观察 ,幼胚最好 ,成熟胚较好 ,成熟种子和茎尖略差。对于茎尖 ,2 ,4 D与KT搭配较好 ;成熟胚而言 ,不加细胞分裂素 ,加适量 2 ,4 D浓度效果较好 ,幼胚愈伤组织诱导和培养不需要细胞分裂素 ,加浓度为 2 .0mg/L2 ,4 D效果较好 ;若加KT ,同时要提高 2 ,4 D浓度 ;成熟种子培养 ,需要细胞分裂素     

高粱基因组学研究进展

高粱是世界上主要的谷物作物之一,是越来越重要的生物燃料作物,是恶性杂草约翰逊草的祖先,同时也是很多具有复杂基因组的热带禾本科植物的植物学模型.因此高粱成为植物基因组学研究的主要对象之一.高粱基因组学研究的丰富历史随着重要的自交系材料BT×623全基因组测序的完成而达到顶峰,这为更好研究高粱基因及其相关功能打下了基础.对甘蔗亚族谷类植物以外的植物的更进一步的基因组特征分析,将有利于发现基因组大小和结构进化的机制,水平和模式,为进一步研究甘蔗和其它重要的经济作物奠定基础.     

Adipokine Levels Are Altered by Shiftwork: A Preliminary Study

Shiftwork is often associated with metabolic diseases, and in the past few years, several cytokines have been postulated to contribute to various diseases, including insulin resistance. The aim of this study was to compare the concentrations of adiponectin, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in samples of young adult men exposed to a fixed (i) night shift (n?=?9), working from 22:00 to 06:00?h; (ii) early morning shift (n?=?6), working from 06:00 to 14:00?h; and (iii) day shift (n?=?7), working from 08:00 to 17:00?h. The fixed night-shift and early-morning-shift samples were considered collectively as a shiftworker group given their work times. Blood samples were collected during the regular working day at 4-h intervals over the course of 24?h, thus totaling six samples. Morphological and physical activity parameters did not differ between the three groups. Total energy intake was lowest on the early morning shifts (p?<?.03). Both shiftworker groups ingested a significantly higher percentage of fat (p?<?.003) and a lower percentage of carbohydrate (p?<?.0005) than the day group. The early morning group had a lower mean 24-h level of adiponectin than the other two groups (p?=?.016), and both the early morning and night groups exhibited higher mean 24-h levels of TNF-α than the day group (p?=?.0001). The 24-h mean levels of IL-6 did not differ significantly between the groups (p?=?.147). None of the groups exhibited a significant circadian effect on adiponectin (p?=?.829), TNF-α (p?=?.779), or IL-6 (p?=?.979) levels. These results indicate that individuals who are enrolled in shiftwork are susceptible to alterations in the secretion of cytokines that are involved in insulin resistance and cardiovascular disease, both of which are known to affect this population. (Author correspondence: tmello@demello.net.br)     

Sorghum phytochemicals and their potential impact on human health

Sorghum is a rich source of various phytochemicals including tannins, phenolic acids, anthocyanins, phytosterols and policosanols. These phytochemicals have potential to significantly impact human health. Sorghum fractions possess high antioxidant activity in vitro relative to other cereals or fruits. These fractions may offer similar health benefits commonly associated with fruits. Available epidemiological evidence suggests that sorghum consumption reduces the risk of certain types of cancer in humans compared to other cereals. The high concentration of phytochemicals in sorghum may be partly responsible. Sorghums containing tannins are widely reported to reduce caloric availability and hence weight gain in animals. This property is potentially useful in helping reduce obesity in humans. Sorghum phytochemicals also promote cardiovascular health in animals. Such properties have not been reported in humans and require investigation, since cardiovascular disease is currently the leading killer in the developed world. This paper reviews available information on sorghum phytochemicals, how the information relates to current phytonutrient research and how it has potential to combat common nutrition-related diseases including cancer, cardiovascular disease and obesity.     

Changes in Levels of alpha-Amylase Components in Barley Tissues during Germination and Early Seedling Growth

Kernels of Klages barley (Hordeum vulgare L.) were germinated for 1 to 4 days on moist sand at 18°C. Representative kernels from each time period were dissected to give the following fractions: scutellum, subscutellar endosperm, aleurone-scutellum interface, remaining aleurone, subaleurone endosperm, and core endosperm. These tissues were analyzed for α-amylase components by isoelectric focusing and rocket-line immunoelectrophoresis. Although aleurone and scutellar tissues appeared to synthesize the same α-amylase components, enzyme was detected first in the scutellum. A larger proportion of scutellar α-amylase was excreted into the endosperm compared to aleurone synthesized α-amylase. Aleurone cells appeared to synthesize appreciably more α-amylase than did scutellar tissue.     

Inhibition of Photosynthesis in Barley with Decreased Levels of Chloroplastic Glutamine Synthetase Activity

Mutant barley plants containing only 8%, 16% or 38% of the wildtype level of glutamine synthetase activity have been isolated.The level of glutamine synthetase activity in the roots of themutant containing only 8% leaf activity was not affected bythis mutation. The plants accumulated high levels of ammoniain leaves exposed to air and although they were able to carryout photosynthetic CO₂fixation normally at low levels of atmosphericO₂, they were unable to maintain wild type rates of CO₂fixationin air. The extent of this inhibition and the extent to whichammonia accumulated in the leaves was dependent on the photonfluence rate intercepted by the plant. When leaves from themutant plant were fed glutamine under non-photorespiratory conditionsfor 40 min before they were transferred to air, the plants exhibitedwild type rates of CO₂ fixation in air but the ammonia contentof the leaves increased to an even higher level. At least inthe short term, therefore, ammonia accumulation was not responsiblefor the dramatic decline in the fixation rate of these mutantsin air. The most probable explanation is that as the supplyof potential amino donors diminished on transfer to air, therewas a restriction on the return of glycerate to the Calvin cyclewithin the chloroplast. Key words: Ammonia toxicity, photorespiration, photosynthesis, GS-deficient barley     

Temperature-Dependent Water and Ion Transport Properties of Barley and Sorghum Roots : II. Effects of Abscisic Acid

Water flux through excised roots (J_v) is determined by root hydraulic conductance (L_p) and the ion flux to the xylem (J_i) that generates an osmotic gradient to drive water movement. These properties of roots are strongly temperature dependent. Abscisic acid (ABA) can influence J_v by altering L_p, J_i, or both. The effects of root temperature on responses to ABA were determined in two species differing in their temperature tolerances. In excised barley (Hordeum vulgare L.) roots, J_v was maximum at 25°C; 10 micromolar ABA enhanced J_v, primarily by increasing L_p, at all temperatures tested (15-40°C). In sorghum (Sorghum bicolor L.) roots, J_v peaked at 35°C; ABA reduced this optimum temperature for J_v to 25°C by increasing L_p at low temperatures and severely inhibiting J_i (dominated by fluxes of K⁺ and NO₃⁻) at warm temperatures. The inhibition of K⁺ flux by ABA at high temperature was mostly independent of external K⁺ availability, implying an effect of ABA on ion release into the xylem. In sorghum, ABA enhanced water flux through roots at nonchilling low temperatures but at the expense of tolerance of warm temperatures. These effects imply that ABA may shift the thermal tolerance range of roots of this heat-tolerant species toward cooler temperatures.     

Effects of Ring D-Modified Gibberellins on Gibberellin Levels and Development in Selected Sorghum bicolor Maturity Genotypes

Plants of early flowering mutant and wild type genotypes of Sorghum bicolor were treated with ring D-modified gibberellins (GAs), and the effects on endogenous GA levels were determined. The growth and timing of floral initiation in 58M plants grown under 18-h days (which significantly delays floral initiation in this short day plant) following treatment with these compounds, relative to GA₃ and GA₅ treatments, were also investigated. Application of the endo-isomer of C16,17-dihydro-GA₅ (endo-DiHGA₅), the exo-isomer of C16,17-dihydro-GA₅ (exo-DiHGA₅), and C16α,17-dichloromethanodihydro-GA₅ (DMDGA₅) altered GA levels in both genotypes. Each ring D-modified GA significantly inhibited shoot growth while significantly decreasing levels of GA₁ and increasing levels of its immediate precursor, GA₂₀. Gibberellin A₈ levels also decreased. Tillering was not affected by any treatment. For the early flowering genotype 58M, grown under noninductive long days, both dihydro-GA₅ isomers promoted floral initiation while shoot growth was strongly inhibited, and floral development was strongly advanced beyond floral stage 4. Gibberellin A₃ and GA₅, applied under the same conditions, promoted shoot growth slightly and gave ``floral-like' apical meristems that did not develop past floral stage 1. These results suggest that the reduced shoot growth of sorghum, which follows application of those ring D-modified GAs, is due to their inhibiting the 3β hydroxylation of GA₂₀ to GA₁, thereby reducing the GA₁ content. That floral initiation was hastened and floral development promoted in genotype 58M by application of both isomers of DiHGA₅ are in contrast to the effects of other GA biosynthesis inhibitors, which act earlier in the GA biosynthesis pathway, but are consistent with results seen for long day grasses. This suggests that endo-DiHGA₅ and exo-DiHGA₅ may be acting directly in promoting floral initiation and subsequent floral apex development of this short day plant under long day conditions. Received October 3, 1996; accepted January 22, 1997     

Levels of Betaine and Betaine Aldehyde Dehydrogenase Activity in the Green Leaves, and Etiolated Leaves and Roots of Barley

The accumulation of betaine and the induction of betaine aldehydedehydrogenase, which catalyzes the last step in the synthesisof betaine, were analyzed in salt-stressed barley leaves. Whenhydroponically grown barley plants were transferred to a mediumthat contained 200 mM NaCl, the levels of both betaine and thetotal extractable betaine aldehyde dehydrogenase activity inthe leaves increased approximately 7-fold and 3-fold when calculatedon the basis of total leaf protein, respectively, over the courseof 7 days. Betaine aldehyde dehydrogenase activity was alsodetected in either etiolated leaves or roots of barley plantsgrown under aseptic conditions. Betaine was detected in bothetiolated leaves and roots at levels that were about 20% ofthat in green leaves when calculated on a fresh weight basis. ¹ This research was supported financially by a research grantfrom the Ministry of Education, Science and Culture (63560080) (Received March 9, 1990; Accepted May 29, 1990)     

热带高梁外源DNA导入寒带高梁引起变异的研究

本文报道了高梁自花授粉后,利用其形成的花粉管通道,将热带高梁外源ＤＮＡ直接导人寒带高梁的结果。由实验结果看出：导入后代的变异主要表现在单穗粒重、茎粗、株高、穗型、壳色等方面。变异的Ｄ２代单株的过氧化物酶及酯酶同工酶酶谱显示了明显的差异。实验结果表明：外源ＤＮＡ片段直接导入受体植物卵细胞、合子或早期胚细胞,部分片段可以被受体细胞ＤＮＡ整合和表达。表明了利用花粉管通道途径来实现外源ＤＮＡ直接导入高梁,进行高梁的种质创新和品质改良是可能的。     

High Levels of Resistance in Agropyron Species to Barley Yellow Dwarf and Wheat Streak Mosaic Viruses

Several Agropyron species were tested for new sources of resistance to barley yellow dwarf virus (Bydv ) and wheat streak mosaic virus (WSMV). With BYDV strain PAV, 11 of the 17 Agropyron species showed no virus transmission when plants were given access feed by viruliferous Rhopalosiphum padi. Similar trials with BYDV strain RMV (vectored by R. maidis) indicated that all plants, except susceptible control plants, remained virus free. Virus status was confirmed by enzyme-linked immunosorbent assays. When plants were mechanically inoculated with WSMV, 11 Agropyron species failed to express symptoms, while five other species showed a segregating response or had some accessions segregating and some resistant. Test results suggest that resistance to BYDV and WSMV in Agropyron species does not appear to be correlated with any specific genome of Agropyron species although most of the Agropyron species containing S genome were resistant to BYDV and WSMV.     

潮霉素在大麦遗传转化中的应用研究

以‘B1202’、‘U202’和‘云引1号’3个大麦品种(系)为试材,研究了潮霉素对大麦愈伤组织生长、分化及成熟种子的影响。结果表明:潮霉素对抗性愈伤的适宜筛选浓度为60 mg/L,分化阶段的适宜筛选浓度为40 mg/L,对转基因后代种子筛选以80 mg/L较为适宜,而不同材料对潮霉素的敏感性存在一定程度的差异。通过PCR检测采用农杆菌介导法转化获得的T0和T1代潮霉素抗性苗,结果证实在大麦遗传转化中采用潮霉素进行筛选是可行的。     

Photoperiod Control of Gibberellin Levels and Flowering in Sorghum

Regulation of rhythmic peaks in levels of endogenous gibberellins (GAs) by photoperiod was studied in the short-day monocot sorghum (Sorghum bicolor [L.] Moench). Comparisons were made between three maturity (Ma) genotypes: 58M (Ma₁Ma₁, Ma₂Ma₂, phyB-1phyB-1, and Ma₄Ma₄ [a phytochrome B null mutant]); 90M (Ma₁Ma₁, Ma₂Ma₂, phyB-2phyB-2, and Ma₄Ma₄); and 100M (Ma₁Ma₁, Ma₂Ma₂, PHYBPHYB, and Ma₄Ma₄). Plants were grown for 14 d under 10-, 14-, 16-, 18-, and 20-h photoperiods, and GA levels were assayed by gas chromatography-mass spectrometry every 3 h for 24 h. Under inductive 10-h photoperiods, the peak of GA₂₀ and GA₁ levels in 90M and 100M was shifted from midday, observed earlier with 12-h photoperiods, to an early morning peak, and flowering was hastened. In addition, the early morning peaks in levels of GA₂₀ and GA₁ in 58M under conditions allowing early flowering (10-, 12-, and 14-h photoperiods) were shifted to midday by noninductive (18- and 20-h) photoperiods, and flowering was delayed. These results are consistent with the possibility that the diurnal rhythm of GA levels plays a role in floral initiation and may be one way by which the absence of phytochrome B causes early flowering in 58M under most photoperiods.     

The Uptake of Amino-Acids and their Incorporation into the Proteins of Excised Barley Embryos

Methods are described by which barley embryos may be excisedand grown under sterile conditions on a medium containing sucrose,minerals, and a complete mixture of amino-acids. Growth underthese conditions was comparable with that of intact seedlingsand the uptake of sugar and amino-acid could be studied withoutdisturbing the metabolic steady state. Purified preparationsof the embryo proteins have been made and the constituent amino-acidsseparated. ¹⁴C labelling in these amino-acids was determinedby a new gas-scintillation method. In an isotopic competitionexperiment embryos were grown in ¹⁴C-sucrose with nitrate oran amino-acid mixture as nitrogen source. The presence of exogenousamino-acids suppressed the incorporation of carbon from carbohydrateinto amino-acid residues of the embryo protein. The degree ofsuppression varied, being undetectable for glutamic acid butalmost complete for lysine and leucine; it appeared to be relatedto the length of the synthetic pathway from carbohydrate tothe amino-acid. The evidence suggested that amino-acids areprotein precursors, and this conclusion was confirmed in furtherexperiments in which ¹⁴C-aspartic acid, -glutamine, -proline,-leucine, or -lysine were supplied singly in a complete mixtureof amino-acids. The ¹⁴C was found predominantly in the amino-acidresidue of protein corresponding to the ¹⁴C-amino-acid supplied,with smaller amounts in other amino-acids of the same or relatedfamilies. Aspartic acid and glutamine yielded appreciable quantitiesof respiratory carbon dioxide, although the contribution wassmall compared to that of sucrose. Little carbon was lost ascarbon dioxide from leucine or lysine. The results are discussedin relation to the role of amino-acids in protein synthesis,and to the existence of feedback control in the amino-acid metabolismof higher plants.     

Salivary Nickel and Chromium Levels in Orthodontic Patients with and Without Periodontitis: a Preliminary Historical Cohort Study

Many periodontal patients may need orthodontic treatment. Alterations in oral environment particularly the reduction of pH in periodontal patients could affect metal ion release from orthodontic appliances. However, there is no study on metal ion release in periodontal patients. The aim of this preliminary study was to comparatively evaluate, for the first time, salivary levels of nickel and chromium in periodontal patients (versus healthy controls) under orthodontic treatment for 2 months. In this in vivo study, 40 subjects were evaluated. Patient selection and standardization of orthodontic treatment protocols were prospectively designed and performed. Two groups of n = 20 each (control: healthy orthodontic patients, cohort: orthodontic patients with periodontitis) underwent similar protocols of fixed orthodontic treatment for 2 months. After 2 months, salivary nickel and chromium concentrations of the case and cohort groups were measured using inductively coupled plasma mass spectrometry (ICP-MS). The values were compared between the two groups using t test. There were 10 men and 10 women in each group. The mean age of patients was 34.6 ± 3.6 years old. The salivary level of nickel was 338.2 ± 235.5 ng/ml and 182.8 ± 116.5 ng/ml in the cohort and control groups, respectively (P = 0.0118). The salivary level of chromium was 7.4 ± 3.15 ng/ml in the cohort and 6.35 ± 2.39 ng/ml in the control group (P = 0.2214). Salivary level of nickel might be considerably higher in periodontal patients undergoing 2 months of orthodontic treatment compared to orthodontic patients with healthy gingivae.