A comparison of three fibre methods for predicting the metabolizable energy content of sorghum grain for poultry

An apparatus designed to simplify analytical procedures for determining fibre in food was used to measure fibre of similar composition to crude fibre, acid-detergent fibre and neutral-detergent fibre in 27 samples of sorghum grain. The metabolizable energy content of these grains for poultry was predicted from the three fibre methods with precision, respectively, of ± 0.49, ± 0.62 and ± 0.53 MJ/kg dry matter. These values corresponded to coefficients of variation of ± 3.0, ± 3.8 and ± 3.3%.The three fibre fractions were highly correlated with each other, and so a simple method that can measure a part of the total fibre is suitable for predicting the energy value of sorghum grain for poultry.     

A simple method for discriminating between full and partial inhibitors

A method is described which provides a more straightforward and reliable discrimination between full and partial inhibitors than do other available procedures. Its advantages are demonstrated by analysis of actual inhibition data. The proposed method proves in certain cases convenient also for the determination of inhibition constants.     

A rapid single-step multiplex method for discriminating between Trichogramma (Hymenoptera: Trichogrammatidae) species in Australia

Inaccurate species identification confounds insect ecological studies. Examining aspects of Trichogramma ecology pertinent to the novel insect resistance management strategy for future transgenic cotton, Gossypium hirsutum L., production in the Ord River Irrigation Area (ORIA) of Western Australia required accurate differentiation between morphologically similar Trichogramma species. Established molecular diagnostic methods for Trichogramma identification use species-specific sequence difference in the internal transcribed spacer (ITS)-2 chromosomal region; yet, difficulties arise discerning polymerase chain reaction (PCR) fragments of similar base pair length by gel electrophoresis. This necessitates the restriction enzyme digestion of PCR-amplified ITS-2 fragments to readily differentiate Trichogramma australicum Girault and Trichogramma pretiosum Riley. To overcome the time and expense associated with a two-step diagnostic procedure, we developed a "one-step" multiplex PCR technique using species-specific primers designed to the ITS-2 region. This approach allowed for a high-throughput analysis of samples as part of ongoing ecological studies examining Trichogramma biological control potential in the ORIA where these two species occur in sympatry.     

A simple method for discriminating between cell membrane and cytosolic proteins

* Transgenic plants expressing either green fluorescent protein (GFP)-genomic DNA or GFP-cDNA fusions have been used as powerful tools to define the subcellular localization of many proteins. Because most plant cells are highly vacuolated, the cytosol is confined to a thin layer at the periphery of the cells, making it very difficult to distinguish among cell wall, cell membrane and cytosolic GFP-fusion proteins. * Plasmolysis tests inform about cell-wall localization of GFP-tagged proteins, but they do not discriminate between its cell membrane and/or cytoplasmic localization. By observing the GFP signal in transgenic protoplasts placed at a hypotonic solution, it was possible to distinguish between cell membrane and cytosolic GFP-tagged proteins. * The osmotic disruption of the protoplast vacuole in the hypotonic solution allows the diffusion of the GFP signal from the cell periphery to the central part of the cell volume when the GFP is fused to a soluble protein. By contrast, such diffusion does not occur when the protein under study is attached to the cell membrane. * The present method is easier, faster and cheaper than subcellular fractionating studies and/or immunoelectron microscopy, which have been traditionally used to discern between cell membrane and cytosolic proteins.     

A rapid autolytic method for the preparation of protein hydrolysate from poultry viscera

Protein hydrolysate was prepared from poultry viscera by a procedure involving autolysis for 6h at pH 2.8 and 55 degrees C followed by heat inactivation, filtration and drying. Recovery of nitrogen in the product was 87%. The process reduced the viable count of bacteria by 5-6logcfu/g. The product contained 84% protein, 6.5% ash and 8.8% moisture. Peptide analysis by gel filtration chromatography showed size in the range of 0.5-5kDa. RPHPLC exhibited the presence of hydrophilic peptides in higher concentration than that in trypsin digest of casein. Protein hydrolysate exhibited presence of all essential amino acids in comparison with reference protein except for methionine and threonine. The product possesses excellent solubility (>93%) over a pH range of 1-12. Efficacy of the product as a bacteriological media or feed supplement is discussed.     

A rapid method for selecting fermentative yeasts at high temperatures

A rapid and efficient method for isolating and selecting thermotolerant and sugar-fermenting yeasts was developed. Several samples from sugar cane by-products could be analyzed at the same time. Yeast cultures could be isolated in about 3 d, in contrast to the conventional methods, and its fermentative ability was qualitatively maintained at the desired temperature. A broad spectrum of temperatures can be tested. Yeasts of generaSaccharomyces andKluyveromyces were easily identified.     

A sensitive and rapid method for identification and characterization of low abundance receptors

An improved method for detection of low intensity radioligand-receptor complexes resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) is described. [3H]Azidopine-labeled 1,4-dihydropyridine (DHP) receptor from skeletal muscle resolved by SDS-PAGE was transferred to nitrocellulose and cut into strips and individual slices were analyzed for radioincorporation by liquid scintillation counting. [3H]Azidopine-labeled DHP binding subunit migrated as a single entity with a mass of 170 kDa and was confirmed using conventional methods. Results were obtained within 4 h after resolution by SDS-PAGE compared to 3-40 days using conventional methods. In addition, detection of extremely low signals (less than 50 cpm/lane), otherwise overwhelmed by background noise using conventional methods, was possible due to removal of free ligand during electro-transfer to nitrocellulose. This technique offers a rapid sensitive, cost effective alternative to fluorography or other conventional gel slice analysis methods for detecting low intensity radiolabeled complexes resolved by SDS-PAGE.     

Relationships between tristimulus colour values and digestibility of grain sorghum by swine

Fourteen grain sorghum cultivars were used to study the degree of relationship between energy and protein digestion coefficients and tristimulus colour values of grain sorghum. Colour values from whole grain, ground dry and ground blended samples of each cultivar were used. Colour values of the ground blended samples were more highly associated with digestibility and nitrogen retention than were colour values of either whole grain or ground dry grain sorghum. Although close relationships were shown by simple correlation coefficients, valid prediction equations could not be developed (P < 0.05) from combinations of these three colour observations. These data indicate that colour difference meter values can be used to develop linear regression equations that would assist in screening grain sorghum cultivars for nutritive value in swine.     

A rapid method for determining the relationship between cDNA clones

We describe a technique for rapidly screening the inserts of plasmids for homology to each other by using DNA fragments isolated in agarose gels to probe Southern blots of DNA prepared by the "miniprep" alkaline lysis method. The procedure includes a technique for labeling DNA fragments in agarose gel slices without further purification. The protocol results in a significant savings in time and expense and a considerable increase in fragment yield over methods involving fragment purification from polyacrylamide or agarose gels.     

A multivariate analysis method for discriminating protein secondary structural segments

Using discriminant analysis, three types of protein secondary structure segments--helices, beta-strands and coils--are discriminated by amino acid sequence information alone. A variable in the discriminant analysis is defined by the amino acid index used to represent the sequence data and by the calculation method used to extract a feature in this representation. Thus, the three types of secondary structure segments derived from a set of non-homologous proteins from the Protein Data Bank are analyzed by 888 variables, which correspond to the mean, standard deviation, 3.6-residue periodicity and 2-residue periodicity for the numerical profiles determined from 222 published amino acid indices. These variables are combined to obtain best discrimination of the three types of segments. When up to three variables are combined, the best discrimination rate was 75%. The variables selected consist of the mean of alpha propensity (or turn propensity), the mean of beta propensity, and the 3.6-residue periodicity of hydrophobicity. This variable selection procedure can also be applied to other types of discrimination problem, once groups of sequence data are properly organized.     

A method for the rapid preparation of 5-vinyluracil in high yield

A method for the rapid preparation of the thymineanalogue, 5-vinyluracil, in 83% yield from 5-(1-hydroxyethyl)uracil via the methanesulphonyl ester is reported.     

A simple and reliable method for discriminating between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae)

Abstract The cotton bollworm Helicoverpa armigera and the oriental tobacco budworm H. assulta are sibling species, both being important agricultural pests. Morphologically, the two insects are almost indistinguishable at the egg, larval and pupal stages. One of the big challenges in the study of these insects, in particular in integrated pest management, is a timely and dependable identification of these insects at their early stages of development. Here, we report a H. armigera‐specific nuclear DNA marker, and demonstrate that it can be employed to reliably discriminate between H. armigera and H. assulta by simple polymerase chain reaction amplification experiment.     

A simple model for selection and rapid advancement of transgenic progeny in sorghum

To select agronomically useful transgenic plants, a large number of transgenic events are initially produced, gene transfer confirmed, and advanced to obtain homozygous lines for testing in field trials. Direct in planta assays for identifying the transgene carriers in the segregating progeny are based on the activity of selectable marker gene and are easy, simple and inexpensive. For this purpose, expression of bar gene as measured by tolerance to damage by glufosinate ammonium, the active ingredient in the herbicide BASTA, was investigated. Dose damage curves were generated by leaf paint tests with BASTA on four genotypes of sorghum. Transgenic plants were characterized in terms of sensitivity to the concentration of glufosinate ammonium. In transgenics, symptoms of BASTA swab tests at different growth stages and PCR analysis for cry1B were carried out and correlated. Germination tests could not be employed for large scale evaluation of transgenic progeny because of mortality of tolerant seedlings after transplantation to soil. Based on the above findings, a simple, inexpensive, time-saving, two-step scheme for effective evaluation of transgenics and their progeny containing bar gene as selection marker using BASTA swab tests is described.     

Protein,nucleic acids and enzyme levels during development in a high lysine sorghum grain

Dry wt, protein, free amino-N, RNA, DNA and the levels of hydrolytic enzymes have been measured in high lysine and normal sorghum grain during development. Dry wt was higher in CSV-5 throughout development. Protein accumulation/grain was lower in the later stages of development of IS 11 758 than in CSV-5. The lower rate of protein accumulation in IS 11758 is not due to a limitation of free amino-N. CSV-5 had a higher proportion of prolamine. A major part of the prolamine in CSV-5 was deposited in a relatively short period from day 24 to 31. In this period much less prolamine was synthesized in IS 11758. RNA content was higher in IS 11758. DNA content, however, was higher in CSV-5 than IS 11758 during early stages of development. RNase activity at maturity was lower in IS 11758. Amylase activity/grain in both was similar, however, on a fr. wt basis it was higher in CSV-5. Protease level/grain was higher in IS 11758.     

A high throughput method and culture medium for rapid screening of phosphate accumulating microorganisms

A novel PA Medium (PAM) for efficient screening of phosphate-accumulating organisms (PAOs) was developed taking Serratia marcescens NBRI1213 as model organism. The defined National Botanical Research Institute’s growth medium (NBRI) supplemented with 0.1% maltose, designed for quantitative estimation of phosphate accumulation was designated as PAM. Our work suggested usage of PAM for efficient qualitative screening and as a microbiological medium for preferential selection of PAOs on Petri-plates. For qualitative screening of PAOs, Toluidine blue-O dye (TBO) was supplemented in PAM, designated as PAM-TBO. Qualitative analysis of phosphate accumulated by various groups correlated well with grouping based upon quantitative analysis of PAOs, effect of carbon, nitrogen, salts, and phosphate accumulation-defective transposon mutants. For significantly increasing sample throughput, efficiency of screening PAOs was further enhanced by adaptation of PAM-TBO assay to microtiter plate based method. It is envisaged that usage of this medium will be salutary for quick screening of PAOs from environment.     

Cofermentation of sweet sorghum juice and grain for production of fuel ethanol and distillers' wet grain

In an attempt to reduce the costs associated with fuel ethanol production from grain, the authors used sweet sorghum juice as a partial or complete replacement for tap-water in mash preparation and fermentation. This juice, which was an unutilized by-product of sweet sorghum silage preservation by the Ag-Bag method, contained 6·5–7·6% (wt/wt) reducing sugar and produced up to 3·51% (v/v) ethanol beers after fermentation. Varying amounts of this juice were mixed with water and corn or wheat, either before or after liquefaction (front-end or back-end loading, respectively). When over 60% juice replacement was used in front-end loading trials, salt buildup, due to required pH adjustments during cooking, inhibited yeast metabolism and thereby reduced yields. This inhibition was not observed during back-end loading trials since acid and base usage during cooking were reduced. However, in all trials we noted yeast inhibition by some factor(s) present in juice from sweet sorghum variety NK 8368. This inhibition was not observed with variety NK 405. If sweet sorghum juice is used to replace 40% of the water and either 12·5% of the corn or 12% of the wheat in mash preparation, production costs can be reduced by $0.032/liter ($0.12/US gallon) for corn and $0.040/liter ($0.15/US gallon) for wheat.     

Response of no-till and conventionally planted grain sorghum to weed control method and row spacing

Grain sorghum can substitute for corn as a full season crop and replace soybeans in double cropping systems with wheat in the southeastern United States. Relatively few studies have been conducted to measure the response of grain sorghum to tillage, weed control method, and row spacing. These experiments were designed to determine the effects of weed control method and row spacing on no-till planted grain sorghum (Sorghum bicolor L. Moench G1516-BR) after wheat (Triticum aestivum L. Coker 68–15) and crimson clover (Trifolium incarnatum L. Bigbee) grown for winter forage in comparison to sorghum planted on a conventionally prepared seedbed. The experiment included 45, 60, and 90 cm row spacings and three weed control regimes: none, mechanical, and chemical. Grain sorghum planted no-till in crimson clover or wheat sod yielded considerably more grain than conventionally planted sorghum. Grain sorghum produced significantly higher yields in 45-cm rows than in 60-and 90-cm row spacings with all three planting methods. Effects of chemical weed control on weed population with all tillage methods and on grain yield with conventional tillage were significant. There were no significant differences in grain protein content due to row spacing or weed control method.