bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil nitrogen analyses and their relation to nitrogen responses in winter wheat
Authors: Eagle D. J. 
Published: November 2006

AbstractAnalyses for nitrate and ammonium were carried out periodically on surface soil samples, obtained at various times throughout the season, from a large number of nitrogen on winter wheat experimental sites.It was found that soil analyses for nitrate alone or nitrate plus ammonia were of no value for prediction of soil‐nitrogen status and nitrogen‐fertiliser responses in winter wheat.Responses of winter wheat to nitrogen fertiliser on freely drained soils where the nitrate nitrogen content of the soil was 15 ppm or more at sowing time were only reduced by this nitrate left over from the previous season when the November–February inclusive rainfall was less than 9 ins.
The lipids of wheat III.—Further studies of the lipids of flours from single wheat varieties of widely varying baking quality
Authors: Fisher N. , Bell Brenda M. , Rawlings Christine E. B. , Bennet Ruth 
Published: November 2006

AbstractThe work on flour lipids reported in Part II* of the series is extended to the lipids of wheats harvested in 1960‐1962 inclusive.The same lipid components were found in each of the varieties studied although English flours contained much larger amounts of unesterified sterols than U.S. varieties of the same crop year. Quantitative lipid analyses demonstrated substantial varietal, seasonal, regional and environmental differences in lipid content and composition of the samples, but tentative correlations previously reported between lipid data and baking performance of the 1960 crop flours were not sustained by 1961 and 1962 crop results. Evidence is presented suggesting that only in very special circumstances would the performance of a flour be limited by the level of unsaturated fat available for the lipoxidase/thiol oxidation mechanism.Application of three quantitative TLC methods to flour lipids is described.
Phospholipids of marine origin. III.—The pilchard (Sardina ocellata, Jenyns) with particular reference to oxidation in pilchard meal manufacture
Authors: De Koninc A. J. , McMullan K. B. 
Published: November 2006

AbstractThe progress of the oxidation of phospholipids and non‐phosphorylated lipids in the manufacturing process of pilchard meal was examined. It was shown that pilchard phospholipids were oxidised to a certain extent in the laboratory drying process, but a severe destruction of phospholipid and non‐phosphorylated lipid fatty acids took place on storage of the meal at room temperature. Phospholipid oxidation was determined by the drop in average unsaturation of the fatty acids and also by the drop in free amino‐nitrogen.In addition, the composition of pilchard phospholipids was determined.
Catechol oxidases, endogenous substrates and browning in developing apples
Authors: Harel E. , Mayer A. M. , Shain Y. 
Published: November 2006

AbstractThe content of o‐diphenols and catechol oxidase activity was followed in developing apples from fruit set to harvest time. Afterwards their level drops, apparently due to conversion to other compounds and cessation of synthesis. Catechol oxidase activity shows a peak after that occurring in content of o‐diphenols. As the fruit ripens, activity drops sharply in the particulate fractions. In the ripe apple a slight amount of soluble enzyme appears. These findings were correlated with the rate of browning of apple slices and the location of enzymes and their substrate in the fruit.Browning of slices could be prevented by dipping them into solutions of I mM‐2,3‐naphthalenediol or 2·5% N‐vinyl‐2‐pyrrolidone. Addition of 1 mM‐sodium ascorbate to the dipping medium improved the efficiency of prevention of browning.
The non‐volatile organic acids of the differently coloured areas of the walls of ‘blotchy’ ripened tomatoes
Authors: Davies J. N. 
Published: November 2006

AbstractA comparative study has been made of the individual non‐volatile organic acids in ethanolic extracts of the red and green areas of the walls of tomato fruit showing symptoms of ‘blotchy’ ripening. The titratable and total acidites of the green areas were lower, and the combined acidity higher than those of the red areas. Potassium concentrations in the differently coloured areas did not differ significantly.Concentrations of the dicarboxylic amino‐acids, pyrrolidonecarboxylic, malic and citric acids in the green areas were all significantly lower than in the corresponding red areas. Citric acid concentrations were much lower and glutamic acid concentrations higher than those found previously in the walls of uniformly ripened fruit of similar colours. The malic/citric acid ratio in the green areas was approximately double that in the red areas. In both cases values were greater than those normally encountered in evenly ripening fruit.The proportions of the total acidity present as malic acid in the differently coloured areas was strikingly similar to that found in the walls of normally ripened fruit of the same colour and variety. On the other hand the proportion of citric acid was markedly reduced in the ‘blotchy’ fruit walls.It is suggested that low citric acid concentrations combined with the persistence of high polyphenol‐oxidase activity may be conducive to ‘blotchy’ ripening of tomato fruit.
Ascorbic acid levels in Ghanaian yams
Authors: Coursey D. G. , Aidoo A. 
Published: November 2006

AbstractThe ascorbic acid (vitamin C) levels of several Ghanaian varieties of yam (Dioscorea spp.) have been investigated. The distribution of the vitamin within the tuber and the effects of different conditions of growth, of length of post‐harvest storage and of different cooking methods have also been studied.Natural vitamin C levels in fresh material are found to vary greatly between varieties, but little with the district where the crop was grown. Most varieties studied contained between 6.5 and 11 mg of ascorbic acid/100g, but some contain as little as 4.5 or as much as 21.5 mg/100g. Losses during storage up to 4 months are comparatively slight in sound tubers, but severe if the tubers are damaged or bruised before storage. The retention of the vitamin during cooking varies from 65 to 95%, with different cooking techniques.Even allowing for these losses in storage and on cooking, the quantities of yam consumed in West African diets should normally be adequate to supply the entire vitamin C requirements of the consumer.
Amino‐acid composition of maturing wheat
Authors: Pomeranz Y. , Finney K. F. , Hoseney R. C. 
Published: November 2006

AbstractAmino‐acids were determined in hydrolysates of two wheat varieties harvested at various stages of maturity, and in flours milled from the wheat samples. During maturation, the concentration in protein of lysine, aspartic acid, glycine. alanine and valine decreased; and concentrations of glutamic acid and proline increased. Milling of wheat into flour reduced the concentrations of lysine, arginine, aspartic acid, threonine, glycine and alanine. Concentrations of glutaniic acid and proline were higher in flour than in wheat proteins. Concentrations of cationic side‐chains in amino‐acids were higher in wheat than in flour, and in both decreased with maturity. Total carboxyl and amide groups were higher in flour than in wheat, and their concentrations increased as the wheat matured. About 84% of the dicarboxylic acids were in amide form. Small changes were observed in concentrations of amino‐acid residues with hydroxylic or hydrophobic groups, and in cystine.
Residues in herbage and silage and feeding experiments following the use of diquat as a desiccant
Authors: Black W. J. M. , Calderbank A. , Douglas G. , McKenna R. H. 
Published: November 2006

AbstractDiquat has been used as a desiccant in silage production. Results of analyses show that diquat disappears rapidly from sprayed herbage so that residues in the silage are at an acceptably low level. No toxic symptoms were observed in long‐term experiments feeding the silage to sheep and cattle and no residues of diquat could be detected in the animal tissues or milk. Of the diquat ingested by sheep 40‐45% is excreted and less than 10% of this is excreted in the urine. The large proportion of diquat unaccounted for may be degraded in the digestive system of the animal.
Stability of agricultural chemicals. I.—Hydrolytic and thermal stabilities of phosphorylated crotonamides
Authors: Brown N. P. H. , Forster A. S. , Furmidge C. G. L. 
Published: November 2006

AbstractThe chemical stability of organo‐phosphorus insecticides is important in determining both the shelf life of their formulations and their rates of decay after application. In common with most organic esters, they are liable to hydrolyse and their stability is considerably impaired by increase in temperature.The hydrolysis of 3‐(dimethoxyphosphinyloxy)‐N, N‐dimethyl‐cis‐crotonamide (‘Bidrid’*) and the corresponding N‐monomethyl derivative (‘Azodrin’*) has been examined at various temperatures and under various pH conditions. Rate constants have been calculated and indicate that the alkaline hydrolysis occurs much more rapidly (approximately 17 times) than acidic hydrolysis. The breakdown mechanism differs between the two cases; acidic hydrolysis produces as its main decomposition products methylphosphoric acid and N‐mono‐ or N, N‐di‐methylacetoacetamide while alkaline hydrolysis produces dimethyl phosphate, methyl alcohol and acetone.Both materials are highly susceptible to increase in temperature and the rates for this decomposition and their significance have been studied. Both the nature of the decomposition products and the rate of thermal breakdown are affected considerably by small quantities of water and free acid in the insecticide.The results are discussed in relation to the existing literature on the decomposition of organo‐phosphorus insecticides and a mechanism of thermal breakdown for both materials is suggested.
The interaction of proteins during gel electrophoresis
Authors: Ewart J. A. D. 
Published: November 2006

AbstractReversible polymerisation and A + B ⇌ C type reactions among proteins during zone electrophoresis may give rise to tailing, extra bands and mobility changes. One or more of these signs are likely to appear with the milder type of interaction, i.e. equilibrium constant in the range 102–108, whether the time to equilibrium is measured in hours or less. Two‐dimensional electrophoresis is more useful for diagnosing interactions. No definite evidence has been obtained for protein‐protein interactions among the slow‐moving gliadins of Bison and Cappelle varieties and the total number of bands probably represents the minimum number of molecular species present.The electrophoretic pattern of a given variety does not appear to alter qualitatively when the year or place of growth is changed. It is estimated that a wheat protein concentration needs to be above ∼0·1 mg/ml to be observable on a starch gel.
Comparison of antioxidants in primary and secondary oxidations
Authors: Shearer G. , Blain J. A. 
Published: November 2006

AbstractThe relative efficacies of a number of antioxidants including mono‐ and bis‐phenols were compared in gel emulsion systems containing linoleate and β‐carotene and subjected to autoxidation and to oxidation by lipoxidase and haemoglobin. They were also tested in liquid emulsions against oxidation of linoleate and vitamin A by lipoxidase. Information on the specificity of antioxidants towards particular systems was obtained.
Polysaccharides of the cocoa pod husk
Authors: Blakemore W. R. , Dewar E. T. , Hodge R. A. 
Published: November 2006

AbstractCocoa pod husk from Ghana was extracted successively with hot water, hot 0·5% anmonium oxalate, cold 10% potassium hydroxide, and hot 20% sodium hydroxide, and the various polysaccharide fractions isolated after dialysis. The hot‐water‐soluble fraction was examined by hydrolysis with 50% formic acid, quantitative determination of the component sugars, and characterisation of the sugars by preparation of crystalline derivatives. The major part of this fraction is a pectic material containing D‐galacturonic acid, D‐galactose, L‐rhamnose and L‐arabinose, but is contaminated with several other polysaccharides, notably a glucan and a mannan. The ammonium oxalate fraction is also a pectin but in a depolymerised form, while the main component sugar of the alkaline extracts is xylose. The insoluble husk residue is probably chiefly cellulose.
Pesticide residues in foodstuffs in Great Britain. II.—Persistent organochlorine pesticide residues in selected foods
Authors: Egan H. , Holmes D. C. , Roburn J. , Tatton J. O'G. 
Published: November 2006

AbstractResidue measurements for persistent organochlorine pesticides in milk, butter, corned beef, beef fat and mutton fat, produced in or imported into Britain in 1963 and 1964 are reported. The levels in mutton fat are compared with levels found earlier; only very low residues are found in most other produce examined though some butter samples contain up to 0·1 ppm of DDT and 0·4 ppm of total DDT equivalent. Levels in the fat of grass and store‐fed animals were indistinguishable; results for milk suggest that the diet of cows in Britain contains very little γ‐BHC or dieldrin.
Pesticide residues in foodstuffs in Great Britain. III.—Arsenic and lead residues in imported apples
Authors: Pocklington W. D. , Tatton J. O'G. 
Published: November 2006

AbstractArsenic and lead residue results are given for apples imported into the U.K. from Australia, Canada, Italy, New Zealand and South Africa in 1962‐1965. The recommended intervals between final application and harvest for lead arsenate treatment against codling moth and other pests in the countries concerned are compared with practice in the U.K. and related to the residues that may occur in the fruit.
A possible contribution of phenolic components to boar odour
Authors: Patterson R. L. S. 
Published: November 2006

AbstractThe odorous phenolic fraction of boar preputial fluid has been analysed by gas‐liquid chromatography. Five of the six phenols detected have been identified by retention data on two stationary phases of differing polarity, and were found to be guaiacol, phenol, p‐cresol, p‐ethylphenol and m‐methoxyphenol. Quantitative data for the five phenols are presented and the contribution of these compounds to the odout of the boar is discussed.
Changes in organic acid composition during incubation of aseptically‐grown grass
Authors: Playne M. J. , Stirling Anna C. , McDonald P. 
Published: November 2006

AbstractThe organic acid composition of aseptically‐grown timothy grass (Phleum pratense) was examined. Changes in organic acids of the grass during incubation in small test tubes with and without the addition of lactic acid bacteria were studied. Malic acid, a major acid of the grass, was broken down during incubation mainly by the activity of bacterial enzymes. The amount of succinic acid was increased by the action of both plant and bacterial enzymes. Citric acid was not detected in the aseptically‐grown timothy grass but two unidentified acids formed a major part of the total organic acid fraction.
The in vitro hydrolysis of leaf proteins. I.—The action of papain on protein extracted from the leaves of Zea mays
Authors: Byers M. 
Published: November 2006

AbstractMaize leaf protein is not digested by papain at 37°, under conditions in which casein is hydrolysed. An increase in temperature has more effect on both the initial rate of reaction, and the final amount of hydrolysis, than an increase in enzyme concentration. Maximum digestion is observed at pH 6‐6 and 70° using KCN‐activated papain: 70% of the substrate N is hydrolysed to non‐protein N. De‐fatting of the protein by neutral solvent mixtures results in only a slight increase in digestion.Soluble N‐containing fractions precipitable by TCA occur at all pH values, but most at pH 7.5 and above. Digestion leads to almost complete solution of the leaf protein at pH 8.6 but the percentage of hydrolysis never exceeds that at pH 6.6. These soluble fractions resemble those found in similar digests of seed proteins.Though in vivo experiments show that protein made from mature wheat leaves has a higher nutritive value than protein from young leaves, there is no corresponding increase in the in vitro digestibility of protein extracted from maize leaves of increasing maturity.
The in vitro hydrolysis of leaf proteins. II.—The action of papain on protein concentrates extracted from leaves of different species
Authors: Byers M. 
Published: November 2006

AbstractThe in vitro digestion by papain of protein concentrates extracted from 14 different species of leaves is described. The extent of hydrolysis varies with species and is probably influenced by preparative technique. The effect of leaf age is less certain: most proteins made by the current standard procedure from any one species, at all stages of growth, have similar digestibilities, but the digestibility of some preparations from mature leaves is less in vitro, but more in vivo, than of preparations from young leaves.The hydrolysis of some fractionated proteins, prepared by controlled heating of leaf extracts, is also described. For all the species examined the ‘chloroplastic’ fraction is digested less, and the ‘cytoplasmic’ fraction more, than the corresponding whole protein: these results agree with those previously obtained in vivo. Differences in the N contents and in vitro digestibility of laboratory‐prepared fractions and those made on a large scale are discussed. Simulated whole protein, made by combining ‘chloroplastic’ and ‘cytoplasmic’ fractions in the correct proportions, is not hydrolysed to the same extent as the corresponding whole concentrate.The percentages of ‘chloroplastic’ and ‘cytoplasmic’ protein, made by the method described here, varies with species, but the ratio seems not to alter as the leaf matures; this could explain the consistent in vitro results usually obtained with recent preparations, irrespective of leaf age. It is suggested that protein digestibility could be assessed rapidly by the method described here as a preliminary to the more thorough, but slower, in vivo tests.
Effect of moisture content during incubation of soil treated with organic materials on changes in sulphate and sulphide levels
Authors: Chaudhry I. A. , Cornfield A. H. 
Published: November 2006

AbstractWater‐soluble sulphate and total sulphide levels were determined during 0, 3, 6 and 12 weeks' incubation (30°) of soil at varying moisture contents (0–133% mwhc) with and without addition of 1 % organic materials (cellulose, compost and dwarf peas, all in a finely ground state). With added peas, conditions were apparently anaerobic at all moisture contents, since immobilisation of sulphate and accumulation of sulphide occurred. Where cellulose or compost were added, sulphide accumulated only at 80% mwhc and higher moisture contents, and increased with moisture content. In unamended soil and soil + compost only sulphate accumulated at 20–60 % mwhc and accumulation increased with moisture content in this range. Where cellulose was added sulphate immobilisation occurred and was less at 20–60% mwhc than at higher moisture levels. At 80% mwhc or more anaerobic effects were predominent. The optimum moisture contents for the accumulation of sulphate and sulphide were 60% and 133% mwhc respectively.
The differential determination of lysine in heated milk. I.—In vitro methods
Authors: Bujard E. , Handwerck V. , Mauron J. 
Published: November 2006

AbstractLysine content and availability were determined in a set of milk samples which had sustained increasing heat treatments. Lysine content was measured after acid hydrolysis of the sample (TLV or x‐value), lysine availability by an enzymic digestion procedure (ALV‐e or y‐value) and by two modifications of the fluorodinitrobenzene method: the direct method (ALV‐f I or z‐value) and Carpenter's corrected straight acid procedure (ALV‐f II or v‐value). The four procedures gave strongly correlated, but numerically quite different results. The enzymic procedure and Carpenter's chemical method produced very similar results for lysine availability. In all heated samples, lysine content was much higher than lysine availability.The direct fluorodinitrobenzene method yielded values intermediate between those for lysine content and ‘true’ lysine availability. A nomograph is presented which accounts for the different conditions of lysine in heated milk and allows the interconversion of the x, y, z and v‐values.
The differential determination of lysine in heated milk II.—Comparison of the in vitro methods with the biological evaluation
Authors: Mottu F. , Mauron J. 
Published: November 2006

AbstractHaving secured the values for lysine content and availability in a set of milk samples by four in vitro methods, we checked the results with those obtained by the in vivo procedure. The biological determination of lysine availability was performed in young rats using a gluten‐zein basal diet supplemented with the appropriate amino acids. The live‐weight gain was used as a measure of the available lysine content of the samples. The results procured by the biological evaluation correlated best with those of the enzymic determination (ALV‐e) and the corrected FDNB method (ALV‐f II). The absolute figures were identical within the 5% confidence limits. All the data presented are in conformity with the working hypothesis that in heated milk the reaction at the epsilon amino group of lysine controls biological lysine availability by transforming this amino acid into an enzyme‐resistant inactivated form.
Adsorption of disulfoton by soil
Authors: Graham‐Bryce I. J. 
Published: November 2006

AbstractAdsorption of the systemic insecticide disulfoton (diethyl S‐[2‐(ethylthio) ethyl] phosphorothiolothionate) by soil was studied using a wet slurry technique. Extraction of soils and solutions after equilibration showed that more disulfoton was lost from solution than could be extracted from soil, principally because of microbial alteration and adsorption by glass. In two contrasting soils equilibration was complete by 3 h and air‐dry soils in the laboratory adsorbed similarly to the moist field soils from which they were derived. Adsorption was fully reversible if desorption took place immediately after uptake when soils were still wet, but the release was modified when the soils were allowed to dry thoroughly between adsorption and desorption. The empirical Freundlich isotherm fitted adsorption results for 17 different soils well. The isotherms had different curvatures but deviations from linearity were small so that linear isotherms provide good approximations. Comparison of the slopes of the best‐fitting linear relationships showed that adsorption was closely related to the amount of organic matter in the soil.