The inheritance of β-amylases in developing barley grain

Three types of -amylase isozyme pattern (Sd^d, Sd^e, and Sd^f) were observed in the doughy endosperm stage of ripening barley grains. From crosses between Sd^d and Sd^f types, it was concluded that these phenotypes are controlled by a pair of codominant alleles. Preliminary studies on the distribution of these -amylase zymotypes indicated that this polymorphism in developing grain is related to a -amylase polymorphism in barley malt.     

The effects of ‘gibberellin-insensitive’ dwarfing alleles in wheat on grain weight and protein content

Summary Three series of near-isogenic wheat lines differing in dwarfing alleles, in the varietal backgrounds of Maris Huntsman, Maris Widgeon and Bersee, and the F₂ grain on intravarietal F₁ hybrids, produced with a chemical hybridising agent, were examined for grain size and protein content. Individual F₂ grains from Rht1/rht, Rht2/rht and Rht3/rht F₁ spikes were classified for Rht genotype by assaying embryo half grains in a gibberellic acid seedling response test, while the remaining half was used for protein determination. Mean grain weight and protein percentage were lower in all homozygous isogenic lines and the Rht/rht F₁ hybrids than in the respective tall lines, in an allele dose-dependent manner. In all the hybrids, the Rht genotype of individual F₂ grains, which segregated within the spikes of F₁ plants, had no significant effects on grain weight or protein. Consequently, the pleiotropic effects of the Rht alleles on these yield and quality components must be attributed to their presence in maternal plant tissues rather than in the endosperm or embryo tissues of individual grains.     

Partial replacement of barley grain for corn grain: Associative effects on lambs’ growth performance

Our objective was to study the positive effects of partial replacement of barley grain for corn in high concentrate diets on growth performance of growing lambs, and to determine the minimum amount of corn needed to produce such effects. Thirty-three male Awassi lambs weaned at 60 days of age were divided into three groups of 11 according to their live weight and offered three isonitrogenous diets. The control diet (B) contained 81 and 14% barley grain and wheat straw, respectively (DM basis). Corn grain replaced barley grain at 10 and 20% of dietary DM for low (LC) and high (HC) corn diets, respectively. Barley had a higher (P < 0.05) rate of digestion (11.5%/h) compared with corn (8.3%/h). The in vitro 30-h digestion extent was also higher (P < 0.05) for barley. The digestion rate for the B diet was higher (P < 0.05) compared with the HC diet, whereas the value for the LC diet was intermediate. Lambs fed LC and HC diets consumed more (P > 0.05) DM (average = 855 g/day) compared with lambs fed B diet (757 g/day). DM and CP digestibilities were similar among diets and averaged 67.0 and 64.2%, respectively. Final BW, BW change and average daily gain (ADG) for lambs fed HC were higher (P < 0.05) compared with B and LC. Moreover, lambs that consumed LC tended (P = 0.12) to grow faster than lambs fed B. Feed to gain ratio was lower (P < 0.05) for lambs fed HC (4.6) compared with B and LC (5.2). In summary, positive associative effects of partial replacement of barley with corn in high concentrate diets for fattening sheep were detected. However, a minimum of 20% replacement of dietary DM from barley with corn was needed to positively improve both performance and feed efficiency.     

The potential of brewer's spent grain to improve the production of α-amylase by Bacillus sp. KR-8104 in submerged fermentation system

Brewer's spent grain (BSG) was used as a solid substrate for the production of α-amylase by Bacillus sp. KR-8104 in a submerged fermentation system. The production of α-amylase was maximized through statistical optimization of the BSG concentration and incubation time using the Doehlert experimental design. The highest tested amount of BSG (5%, w/v) in the optimization process resulted in a 5.1-fold enhancement of the response. Subsequently, we studied the role of the water-soluble and -insoluble fractions of BSG in the production of α-amylase. The results revealed that whole BSG had a greater effect on the production of α-amylase than each fraction had separately. Finally, when we examined the potential of BSG to replace the constituents of a medium formula, we observed that simultaneously adding BSG, omitting dextrin, and reducing the other ingredients concentration in the culture medium improved the production of α-amylase and made the production process more economical.     

A hemicellulosic β-D-glucan from the endosperm of sorghum grain

A hemicellulosic β-D-glucan of $\text{d.p.}$ ≈26 has been isolated from the endosperm of sorghum grain. Methylation analysis, partial hydrolysis with acid, and periodateoxidation studies showed that the glucan is linear and has both (1 → 3)- and (1 → 4)-linked D-glucopyranose residues in the ratio of 3:2. The low, positive, specific rotation and chromium trioxide oxidation studies indicated that the D-glucose residues are β-linked.     

Bifunctional inhibitor of α-amylase/trypsin from wheat grain

A trypsin inhibitor, isolated from whole-wheat grain (Triticum aestivum L.) by the method of biospecific chromatography on trypsin-Sepharose, was potent in inhibiting human salivary α-amylase. The bifunctional α-amylase/trypsin inhibitor was characterized by a narrow specificity for other α-amylases and proteinases. The high thermostability of the inhibitor was lost in the presence of SH group-reducing agents. The inhibitor-trypsin complex retained its activity against α-amylase. The inhibitor—α-amylase complex was active against trypsin. Studies of the enzyme kinetics demonstrated that the inhibition of α-amylase and trypsin was noncompetitive. Our results suggest the existence of two independent active sites responsible for the interaction with the enzymes.     

Effect of environment on multi-element grain composition of pigeonpea cultivars under farmers’ conditions

Pigeonpea (Cajanus cajan L. Millsp.) is often intercropped with maize (Zea mays L.) in eastern and southern Africa. The studies aimed at determining how different genotypes of pigeonpea responded in terms of grain element composition under farmers’ cropping conditions. Approx. 78 farmers participated. They came from four study sites in Tanzania (Babati and Gairo) and Malawi (Nyambi and Ntonda) that differed in terms of tradition for using pigeonpea as well as in environmental conditions. The individual grain weight of the pigeonpea crops from Malawi were 21% (P < 0.05) higher than those from Tanzania. However, only B, Cu, Mo, N, Ni, P and S were affected by grain weight (P < 0.05). Weak (r ² < 0.10) negative correlations existed between grain yield and the grains’ proportion of Ca, Mg, P, and Zn. The proportion of every element, with the exception of Cr, in the grain differed between sites (P < 0.05) but not between varieties (P > 0.05). The amounts of K, Mg, S and Fe accumulated per grain were slightly lower (P < 0.11) in ICEAP00040 compared to the more traditional varieties. Variations in DTPA-exchangeable Zn and Fe in the soil were not reflected in grain concentrations but grain P had a curvi-linear relation (r ² = 0.44) to the soil NaHCO₃^–-exchangeable P indicating P deficiency for several soils. The P and Zn content were correlated (r ² > 0.41) as the only two grain elements. Unique fingerprinting by multivariate statistics was possible for each site when using the element proportion of the grain dry matter with or without soil characteristics. In all cases, different elements contributed with varying weight to the discrimination between the sites. However, it was not possible to distinguish between the varieties when considering all four environments. Reducing the models to include Fe, K, Mg, P, S and Zn only, did however allow some distinction between the two genotypes, which indicates that genotypic variability is expressed in a fairly limited number of elements. In the cases of Gairo and Nyambi, it was possible to distinguish between varieties. In the case of Gairo, the models distinguished between ICEAP00068 and the others, i.e. ICEAP00040 and Babati White where ICEAP00068 was associated with a higher proportion of Fe, P, S, and Zn in the grain. In the case of Nyambi, the models distinguished between ICEAP00040 and ICP9145 where ICEAP00040 was associated with a lower proportion of Ca, Cu, Fe, Mn, Ni, P, S, and Zn and a higher proportion of Cr and Na in the grain. It is thus possible in some cases to separate varieties based on multi-element grain content across a relatively narrow environmental gradient but not generally across all environments. These findings should be included in breeding programmes focusing on the improvement of the nutritional value of our food crops.     

Bioactivities of extracts from Acorus gramineus on four stored grain pests

1 INTRODUCTIONControl of the stored product insects around theworldis primarily dependent upon insecticides such asorganophosphates and pyrethroids , and gaseousinsecticides such as methyl bromide and phosphine .Although effective ,their repeated use for …     

The Badge of Jiuzhai

1. The background is a maple leaf, whose vein is the transformation of the first letter of "Jiu", that is J. In the front, there is a waterfall, which is the transformati on of Z, the first letter of Zhai. This makes "Jiuzhai" obvious. The first letter of China, "C", is transformed into a globe, symbol-     

Determination of correction factors of 3H-β-self-absorption for quantitative evaluation of grain number in autoradiographic studies

Summary Deparaffinized and Feulgen-stained sagittal sections of the mouse brain were studied interferometrically in order to measure optical path differences of euchromatin and heterochromatin of various cell types. Furthermore, the ratio eu-: heterochromatin of each cell type was determined. From these data mass densities of karyoplasm and, finally, correction factors of ³H--self-absorption were calculated for comparing grain numbers of different cell types in quantitative autoradiographic studies after application of tritium-labelled substances. Remarkable differences of correction factors up to a factor of 2.18 were found. Furthermore, the actual section thickness was determined interferometrically. A reduction to about 0.60 of the microtome setting was measured in two different areas of the brain. Using mass densities together with actual section thickness correction factors for a thickness of 1 m were calculated. This was done also for cell types outside the brain the data of which were taken from literature. Thus, differences in correction factors up to about a factor of 4 were found pointing out the importance of considering ³H--self-absorption in quantitative autoradiographic studies.Dedicated to the sixtieth birthday of Prof. Dr. Brigitte Maurer-Schultze, Würzburg.     

Internodes of grain legumes — New location for xylem parenchyma transfer cells

Summary Xylem parenchyma transfer cells were observed in the primary and secondary vascular tissue of stem internodes of 21 in 28 species of grain legumes. Their structural features were similar to those of other transfer cells. The relationships of these cells to transfer cells at nodes were investigated. Non-nodulated seedlings ofPhaseolus vulgaris L. formed internode transfer cells if provided mineral nutrients through their roots, but not if grown in distilled water or fed nutrients entirely through their leaves. Wall ingrowths formed in parenchyma of primary xylem ofPhaseolus just before full extension of an internode. The significance of this new location for transfer cells was discussed.     

The Ascent of Man?

Anyone who cares about the moral and social implications of genomics, genetic engineering and biotechnology should read Michael J. Sandel's article, 'The Case Against Perfection', in the April 2004 issue of The Atlantic Monthly.     

The message of ‘The Other North Sea’

This paper explains the objectives of organising the symposium ‘The Other North Sea’. A major goal is the submission of the conclusions and content of this symposium to the North Sea Task Force, an initiative of the Second Conference on the Protection of the North Sea (London, 1987) which is responsible for preparing a Quality Status Report on the North Sea by mid-1993. The conclusions and recommendations of the symposium are summarised and presented to the North Sea Task Force in connection with the preparations for the 1993 Quality Status Report. The paper stresses the need to subdivide the North Sea into areas of ecological entity and underlines the advantages of using diatom and meiofauna assemblages as indicators for present and past environmental actors in sediment conditions. A plea is also made for the promotion of research to improve understanding of disturbance of sensory perception and behaviour as an ecologically relevant early warning signal. The major role of fisheries in inducing changes of seabird and harbour porpoise populations is highlighted.     

The animal origin of SARS-CoV

The first case of severe acute respiratory syndrome(SARS)in Guangdong province was reported on2Jan2003,whileretrospective survey has datedthe first index case on16Nov2002.In months that followed,pandemic of SARS widelyspread over the world until July2003,infecting8454people and claiming908deathsin39countries andregions global-ly.On16Dec2003,a32years old photographerlivinginsuburban Guangzhou presented withsymptoms of SARSinfec-tion.There were3other ensuing cases betweenthe end of2003and…     

The Bioarchaeology of Mummies评介

<正>木乃伊(Mummy)一词源自波斯语Mumiai,是指在物理或化学机制下软组织得以保存的生物遗骸。作为考古学研究的一大主题,木乃伊已被证明含有大量生物医学和生物人类学信息,研究人员可以利用生物学、医学手段从遗骸中将其恢复,具有独特的研究价值。     

The stereospecificity of α-chymotrypsin

1. The rates of deacylation of acyl-alpha-chymotrypsins in which the hydrogen-bonding capacity of the acylamino group of the substrate has been systematically removed were measured. 2. The ratio of deacylation rates of l- and d-acyl-enzymes is found to depend largely on the existence in the substrate of an amido -NH- group. 3. The data presented agree with the postulate that the stereospecificity of alpha-chymotrypsin is exercised in catalytic rather than binding steps, and that the active site of the enzyme presents three loci to the substrate: the site containing the catalytic functionalities (including serine-195), the hydrophobic area for amino acid side-chain binding, and a hydrogen-bond acceptor site for acylamino group binding. 4. It is noted that, though the hydrogen-bonding site is crucial for the stereospecificity, the free energy of binding of substrates and inhibitors is dominated by the hydrophobic interaction. 5. It is tentatively proposed that alpha-chymotrypsin selects a high-energy conformation of the substrate when the latter binds at the enzyme's active site.