bluuebunny/crossref_metadata_2025_split huggingface dataset:
The determination of acid‐soluble nucleotides in milk by improved enzymic methods: A comparison with the ion‐exchange column chromatography procedure
Authors: Hernández Angel Gil , Sánchez‐Medina Fermín 
Published: October 2006

AbstractEnzymic methods have been developed to measure adenosine, cytidine, guanosine, and uridine‐5′‐monophosphates and also total adenine, cytidine, guanine, and uridine nucleotides in cow, goat, sheep, and human milk. Uridine‐diphosphate glucose, uridine‐diphosphate galactose, and orotate have also been measured by specific enzymic methods. There were no significant differences between the values obtained by ion‐exchange column chromatography and enzymic methods. These last procedures were faster, simpler, and less time consuming to perform compared with conventional methods in use at present. Correlations have been established between the nucleotide contents in milk and the optical density of protein‐free milk extracts from different species. Simple mathematical formulae allow estimation, with an error < 5 %, of the nucleotide contents of cow, goat, sheep, and human milk samples, by measuring the optical density of the corresponding protein‐free milk extracts at 250, 260, and 280 nm.
Kinetics and equilibria of tea infusion: Kinetics of extraction of theaflavins, thearubigins and caffeine from Koonsong broken pekoe
Authors: Spiro Michael , Siddique Shama 
Published: October 2006

AbstractThe rates of infusion of theaflavins, thearubigins, and caffeine from Koonsong Broken Pekoe into water were measured at 79.5 and 94.0°C. The kinetic data have been interpreted in terms of a simple two‐phase model, and the rate constants of infusion and of re‐absorption were calculated. At low infusion times thearubigins were extracted faster than theaflavins, with the caffeine rate intermediate. However, the rate constants for the overall infusion process were quite similar for the three constituents. The corresponding activation energies are small as are those calculated from Long's data on the rate of extraction of all soluble material.
Colonisation and aflatoxin formation by Aspergillus spp. on brown rices differing in endosperm properties
Authors: Ilag Lina L. , Juliano Bienvenido O. 
Published: October 2006

AbstractAspergillus flavus Link and A. parasiticus Speare differed in sporulation and aflatoxin B1 formation on 15 brown rices differing in starch properties and protein content. There was no significant correlation between the degree of spore formation by the fungi and the amount of aflatoxin they produced in the rice samples. Differences in sporulation and aflatoxin production were not correlated with the dimensions (weight and hardness) of brown rice nor with the protein content, alkali spreading value, amylose content and gel viscosity of milled rice. Aflatoxin B1 was mainly concentrated in the bran layers. Histological examination revealed that the hyphae of A. flavus entered through cracks in the periderm and penetrated the endosperm.
Gel filtration chromatography of protein extracts from Lucerne (Alfalfa)
Authors: Knuckles Benny E. , de Fremery Donald , Kohler George O. 
Published: October 2006

AbstractSeveral gels used for gel filtration were compared for their effectiveness in separating protein from lucerne (alfalfa) extracts. Separations of protein and non‐protein components on Sephadex G‐50 and Bio‐Gel P‐10 were good at loading levels up to 35% of column volume. This separation was maintained upon concentrating the extract in an ultrafilter. The lyophilised protein concentrates were cream coloured, were very soluble, and had a good balance of amino acids.
An improved viscometric method for monitoring starch degradation
Authors: Dickinson Eric , McKay James E. , Thomas Verian D. , Warunek Catherine 
Published: October 2006

AbstractThe advantages of a commercial constant‐stress viscometer (the Deer Rheometer) for monitoring the kinetics of starch degradation are presented. The concentric cylinder arrangement is particularly appropriate for studying non‐Newtonian dispersions at the early stages of degradation. The rates of dissolution of wheat and ‘soluble’ starches in dimethylsulphoxide at 25°C are clearly distinguished, and the sensitivity of the extent of dissolution to the degree of agitation is demonstrated. The instrument provides a precise and convenient technique for following the hydrolysis of ‘soluble’ starch by α‐amylase. The reliability is confirmed by observing that the viscometrically determined optimum enzymic activity agrees with that found by chemical methods.
Egg weight and production responses of laying hens fed rice pollard
Authors: Balnave Derick 
Published: October 2006

AbstractConcentrations of rice pollard of 85 and 420 g kg−1 were included in iso‐energetic layer diets without any detrimental effect on production. Immediate improvements in egg weight and egg gradings were observed as a result of feeding rice pollard from point‐of‐lay; these presumably reflected increased dietary concentrations of linoleic acid. Varying responses to the two dietary rice pollard concentrations indicated strain differences in linoleic acid requirements during the early laying period. Rapid reductions in egg weight and egg gradings occurred when the rice pollard was removed at 48 weeks of age, the effect being most noticeable in birds previously fed the high concentration of rice pollard.
Studies on plant gums: Characterisation of neem (Azadirachta indica) gum protease as a glycoprotein
Authors: Nayak B. Ramakrishna , Pattabiraman Thillaisthanam N. 
Published: October 2006

AbstractA protease has been purified from neem gum by chromatography of the partially demetallised gum on TEAE‐cellulose and by affinity chromatography on concanavalin A‐Sepharose 4B. The protease was found to be homogeneous by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis and by chromatography on Sephadex G‐200 in the presence of 6M urea. The protease contained covalently bound carbohydrate to the extent of 19%. The monosaccharide units mannose, glucosamine, arabinose, galactose, fucose, xylose and glucose in an approximate molar ratio of 4:3:3:2:2:1:1, constituted the carbohydrate portion of the protease. The linkage between the carbohydrate and protein segments in the protease was found to be an N‐glycosidic bond involving glucosamine.
The effects of ascorbic acid and sorbic acid on N‐nitrosamine formation in a heterogeneous model system
Authors: Massey Robert C. , Forsythe Lynda , McWeeny David J. 
Published: October 2006

AbstractThe effects of competitive nitrosation by ascorbic acid and sorbic acid on N‐nitrosamine formation were studied in a heterogeneous protein‐based model system containing a 20% non‐aqueous phase. The reactions were examined at 37°C with an aqueous phase pH of 5.25. Under certain conditions ascorbic acid enhanced the nitrosation of secondary amines. The overall extent to which ascorbic acid affected N‐nitrosation was found to depend on the time‐scale of the reaction and also the phase in which N‐nitrosamine formation occurred. Sorbic acid reduced N‐nitrosation in both phases of the heterogeneous system.
The influence of dietary branched‐chain fatty acids on the fatty acid composition of tissue lipids of rats
Authors: Smith Alistair , Lough A. Kenneth , Earl Charles R. A. 
Published: October 2006

AbstractBranched‐chain fatty acids (BCFA) were prepared as a concentrate from the adiposetissue lipids of barley‐fed lambs. The BCFA was included in a stock Oxoid ration at levels of 2.5–15% by weight and these diets were given to appetite to female weanling rats for up to 14 days. The influence of the diets on inter alia growth‐rate and fatty acid composition of tissue lipids was compared with the effect of the same stock diet with inclusions at a level of 5% by weight of 3‐methylhexadecanoic acid (3‐MHD), 4‐methylhexadecanoic acid (4‐MHD), 3,7,11,15‐tetramethylhexadecanoic (phytanic) acid and n‐hexadecanoic (palmitic) acid which, with the stock ration, served as control. Rats receiving diets containing up to 7.5% BCFA grew almost as well as did those given palmitic acid whereas the animals offered the diets containing 3‐MHD, 4‐MHD or 10% BCFA barely subsisted. Rats given 10% BCFA or phytanic acid became moribund within 3 days. BCFA accumulated to widely varying degrees in the lipids of the main internal organs. The higher proportions of these acids constituted some 40–60% of the total fatty acids of the lipids of kidney, liver and heart and were associated with diets containing 10% and 15% BCFA and 5% 3‐MHD. The lower proportions of the branched acids in the lipids of these organs were in the range 15–25% of the total fatty acids and related to diets that included 2.5% BCFA and 5% 4‐MHD. In contrast to the changes in fatty acid composition of the lipids of the main internal organs, those of the central and peripheral nervous systems were only minor, the proportions of branched acids amounting to some 3% in brain tissue and up to 14% in sciatic nerve. Clearance of branched acids from tissue lipids of the main internal organs was almost complete after the animals were returned to the basal diet for 14 days but the loss of branched acids from nerve tissue was evidently less rapid.
Natural plant enzyme inhibitors. Protease inhibitors in millets
Authors: Chandrasekher Gudiseva , Raju D. Suryaprasad , Pattabiraman Thillaisthanam N. 
Published: October 2006

AbstractProtease inhibitory activities were screened in 12 varieties of pearl millet (Pennisetum typhoideum), 12 varieties of echinocloa (Echinocloa colona), 12 varieties of setaria (Setaria italica), 11 varieties of kodo (Paspalum scorbiculatum), 13 varieties of proso (Panicium miliaceum), 11 varieties of miliare (Panicium miliare), 29 varieties of sorghum (Sorghum bicolor) and four varieties of ragi (Eleusine coracana). Proso, miliare and kodo had no detectable inhibitory activity. Pearl millet, setaria and echinocloa millets displayed only antitryptic activity. Ragi had both antitryptic and antichymotryptic activity. Two varieties of sorghum had neither antitryptic nor antichymotryptic activity. In most other strains of sorghum, the antichymotryptic activity was more than the antitryptic activity. Pearl millet, setaria, sorghum and echinocloa extracts inhibited the proteolytic activity of both human and bovine pancreatic preparations.
Distribution of nitrapyrin [2‐chloro‐6‐(trichloromethyl)‐pyridine] and 2‐chloro‐6‐(dichloromethyl)‐pyridine in red beet treated with nitrapyrin
Authors: Kallio Heikki , Sandholm Jari 
Published: October 2006

AbstractIn red beet (Beta vulgaris L. var. conditiva) the main degradation product of added nitrapyrin [2‐chloro‐6‐(trichloromethyl)‐pyridine] has been shown to be 2‐chloro‐6‐(dichloromethyl)‐pyridine. The distribution of these two compounds in beet was also studied. The highest content of nitrapyrin residues (dry weight) was found in the root tips and the petioles; the peel contained more than the leaf laminae or other parts of the root. The higher the nitrapyrin content, the higher was the ratio of nitrapyrin to its dechloro form. No clear linear correlation was observed between the content of nitrapyrin and its dechloro form. The amounts of nitrapyrin residues in beet treated with Ca(NO3)2 were smaller than in the respective samples of beet fertilised with urea or NH4NO3.
A study of polyphenols in the seeds and leaves of guar (Cyamopsis tetragonoloba L. Taub)
Authors: Kaushal Gur P. , Bhatia Iqbal S. 
Published: October 2006

AbstractGallotannins, gallic acid, gallic acid derivatives, myricetin‐7‐glucoside‐3‐glycoside, kaempferol‐7‐glucoside‐3‐glycoside, kaempferol‐3‐rutinoside, kaempferol‐3‐glucoside, chlorogenic acid, caffeic acid and ellagic acid were derived from guar seeds and identified by chromatographic and spectral analysis. Myricetin‐7‐glucoside‐3‐glycoside, kaempferol‐7‐glucoside‐3‐glycoside, kaempferol‐3‐rutinoside, kaempferol‐3‐glucoside, quercetin‐3‐rutinoside, 2,3,4‐trihydroxybenzoic acid, texasin‐7‐O‐glucoside, daidzein‐7‐O‐glucoside, chlorogenic acid and p‐coumaryl quinic acid were found in guar leaves. The polyphenolic content of guar seeds depended on the stage of maturity varying from 1.26 to 0.69% total phenols; 0.49 to 0.12% gallic acid; 0.5 to 0.21% gallotannins; and 0.13 to 0.23% flavonols (all as percentage dry matter). The polyphenolic content of guar leaves varied from 0.74 to 1.24% total phenols; 0.18 to 0.84% flavonols; and 0.05 to 0.24% hydroxycinnamic acids in the dry matter of guar leaves.
The aerobic deterioration of grass silage and its effect on the water‐soluble carbohydrate and the associated heat production
Authors: Rees D. Victor H. 
Published: October 2006

AbstractExperiments are described which investigated the aerobic deterioration of silage under laboratory conditions. Relationships were established between: (i) dry matter (DM) loss and the temperature rise (t) of the silage (° C) (percentage DM loss = 0.17t−1.480; r=0.9646, significant at the 0.01% level); (ii) daily DM loss, depth and time (percentage daily DM loss = −0.1394–0.00633 × depth (mm) + 0.780 × day −0.059 × day2; r = 0.9576, significant at the 0.1 % level); and (iii) total DM loss and the final pH of the silage (pH = 3.79 + 0.13 percentage DM loss; r = 0.8355, significant at the 0.01% level). The indications were that most if not all of the DM loss was accounted for by the losses of water‐soluble carbohydrate. The field application of the work is discussed.
Evaluation of stabilised diazonium salts for the detection of phenolic constituents of plant cell walls
Authors: Harris Philip J. , Hartley Roy D. , Barton G. Edgar 
Published: October 2006

AbstractSections from laminae of perennial ryegrass and internodes of the annual ryegrass, Lolium termulentum, and red clover were treated with 11 stabilised diazonium salts at pH values between 5 and 9. The walls of cell types which fluoresced blue in ultraviolet radiation in the presence of NH3, and which gave red colorations with phloroglucinol‐HCl and Cl2‐Na2SO3 suggesting the presence of lignin, also gave colours with the diazonium salts. After treatment with the salts, lignified walls of grasses gave colours that were of longer wavelength than similar walls of red clover. The most distinct and most intense red colorations were given by p‐nitrobenzenediazonium tetrafluoroborate. Lignified walls were either undigested or only partially digested by rumen liquor. In contrast, unlignified walls gave little or no colour with the diazonium salts and were readily digested by the liquor.
Effect of water immersion on the microtopography of the skin of chicken carcasses
Authors: Thomas Connor J. , McMeekin Thomas A. 
Published: October 2006

AbstractWater‐immersion cleaning and chilling of poultry carcasses caused the skin to swell and exposed deep channels and crevices in the skin surface as a result of water uptake. These changes were demonstrated by electron microscopy and were shown to be dependent on the time of immersion and the temperature of the water. Addition of sodium chloride to the immersion medium and manipulation of the medium pH did not markedly affect or prevent these changes. The implications of these changes for microbial contamination during water‐immersion chilling are discussed.
A method for the detection and estimation of trace levels of theobromine in mixed horse feed
Authors: Taylor Philip W. 
Published: October 2006

AbstractA method for the detection and estimation of theobromine in compounded horse feed by high‐performance liquid chromatography (h.p.l.c.) is presented. The sample is extracted by refluxing with distilled water and clarified by the addition of Carrez reagents. The level of co‐extractives is reduced by precipitation by the addition of 4 vols of acetone, and a measured volume of the filtrate transferred on to a silica column for clean‐up. The theobromine is eluted with chloroform (85%)‐propan‐2‐ol (15%) and the eluate evaporated to dryness. The residue is dissolved in water and analysed by h.p.l.c. (using a reverse‐phase column and ultraviolet detection at 272 nm). The method has been tested on mixed horse feeds and their ingredients. Theobromine recoveries were in the range 78–86% and concentrations down to 2 mg kg−1 could be measured. Three ways to confirm positive results are presented.
Chemical composition of mature seeds from different cultivars and lines of Vicia faba L.
Authors: Barratt Daniel H. P. 
Published: October 2006

AbstractWhole mature seeds and cotyledons (testa and embryonic axes having been removed) from 30 cultivars or lines of Vicia faba were analysed for their chemical composition. Cultivars and lines showed variation in crude protein (26–38%, cotyledons; 26–39%, whole seeds), starch (41–58%, cotyledons; 35–53%, whole seeds), ethanol‐soluble sugars (5–9%, cotyledons; 6–11%, whole seeds), uncombined amino acids (0.73–1.5%, whole seeds) and uncombined arginine (0.34–1.34%, whole seeds). Crude protein and carbohydrate (i.e. starch plus ethanol‐soluble sugars) were inversely related. The large‐seeded cultivars and lines (above 700 mg fresh weight) had a lower concentration of starch but a higher concentration of ethanol‐soluble sugars than small‐seeded ones with an equivalent protein concentration. Significant correlations were found between the protein concentration and that of uncombined amino acids and of arginine.
Evaluation of the effect of formic acid and level of formaldehyde application before ensiling on silage protein degradability
Authors: Siddons Rodney C. , Beever David E. , Kaiser Alan G. 
Published: October 2006

AbstractThe effect of the application, before ensiling, of formic acid alone, and together with increasing levels of formaldehyde, on the degradability of the protein of ryegrass and red clover silages has been assessed on the basis of nitrogen solubility in mineral buffer; susceptibility of N to degradation during in‐vitro incubation with either rumen microorganisms, acid pepsin or neutral protease; and N disappearance when the silages were incubated in situ in Dacron bags in the rumen of sheep receiving dried grass. The relative effects of the additives were generally consistent for both crops and with all procedures: formic acid either had no effect or reduced degradability by only a small amount, whereas a mixture of formic acid and formaldehyde was more effective than formic acid alone in protecting protein from degradation, and degradability decreased in a curvilinear manner with increasing levels of formaldehyde application. Absolute values for protein degradability based on buffer solubility and in‐vitro degradation by rumen microorganisms were very similar but lower than those based on digestion with proteolytic enzymes which in turn were lower than those obtained with the rumen in situ procedure. Buffer solubility and in‐vitro incubation with rumen microorganisms also showed much bigger differences between the formic acid‐treated and the formaldehyde‐treated silages than the other methods.
The influence of growing season on the determination of protein in hard red spring wheat by the biuret reaction
Authors: Williams Philip C. , Butler Constance D. 
Published: October 2006

AbstractProtein was determined by a biuret procedure in three series of Hard Red Spring wheat samples, two of which represented different growing seasons, the third being drawn from randomised railcar lots. When calibrations were based on samples drawn from single individual seasons, differences in calibration slopes caused significant errors in the prediction of protein in samples drawn from different seasons. The analysis of the randomised lots of wheat using calibrations based on single individual seasons gave errors which were intermediate between those obtained for samples from individual seasons. However, these were closer to the results obtained using the calibration prepared from samples of the season, the wheat from which the randomised lots were mainly composed. The precision of the biuret test for all three series was superior to that of the Kjeldahl test.
Determination of tyrosine by a modified Millon's reaction and its application to potato tuber extracts
Authors: Samotus Boguslaw , Leja Maria , Scigalski Andrzej , Dulinski Jerzy , Siwanowicz Robert 
Published: October 2006

AbstractA method for determining tyrosine by a modified Millon's reaction and suitable for applying to potato tuber extracts is presented. The deproteinised extract is first treated with a high concentration of mercuric acetate and sodium carbonate. The complex of tyrosine formed with basic mercuric carbonate is then dissolved in sulphuric acid and the intensity of the colour determined photometrically after the formation of Millon's chromophores with sodium nitrite. High concentrations of mercuric and hydrogen ions were necessary in the preliminary purification to minimise their influence on the colour intensity after addition of sodium nitrite. Because of its simplicity the method can be used routinely for large number of samples and will be of use to potato breeders when examining new cultivars.
Proteolysates from slaughter‐house blood
Authors: Quaglia Giovan B. , Massacci Angelo 
Published: October 2006

AbstractPrevious studies have shown the anticlotting effect of papain on slaughter‐house blood to be due to its proteolytic activity on fibrin. This has suggested its possible use in a protein recovery process. Blood proteolysate has been obtained using microbial proteases or papain; the haemolysis of the cells was then effected and the haem extracted with acidified acetone to decolourise the product.
Ethanol denaturation of soya bean protein antigens
Authors: Sissons John W. , Nyrup Allan , Kilshaw Peter J. , Smith Roy H. 
Published: October 2006

AbstractGlycinin and β‐conglycinin, globular proteins present in soya bean meal, were denatured by extracting the meal with ethanol under several different conditions of alcohol concentration and temperature. Antigenic activities of these proteins in saline extracts of the processed meal were determined by haemagglutination inhibition assay and immunoelectrophoresis. Products extracted with low (< 30%) and high (>96%) concentrations of ethanol at 70–80°C retained antigenic activity, whereas samples prepared with 55–76% ethanol at 70–80°C contained very little extractable antigenic protein. Antigenic activities of glycinin and β‐conglycinin were relatively high in products extracted with concentrations of ethanol between 57–86% when the extraction temperature was <50°C.
Heat stability of fungal pectolytic enzymes
Authors: Harris Jane E. , Dennis Colin 
Published: October 2006

AbstractStudies on the endopolygalacturonases (endo‐PGs) produced by Rhizopus. and Mucor species showed a similar pattern of production of isoenzymes in both apricot and strawberry tissue, although the relative proportion of the isoenzymes varied between fruits. The endo‐PGs showed maximum activity between 40 and 60°C and all of the isoenzymes were able to macerate fruit tissue. The major isoenzymes were very heat‐stable, retaining activity after heating for 10 min at 100 and 120°C, and many showed a bimodal inactivation, being least stable at 50–60°C. Therefore, the presence of heat‐stable and heat‐labile isoenzymes did not account for the marked difference in the heat stability of endo‐PGs when heated in tissue of apricot and strawberry. This difference is considered to be due to the phenolics present in strawberry tissue, since the endo‐PGs showed similar heat stability to those produced in apricot, when strawberry tissue was treated with polyvinylpolypyrrolidone or polyamide (known phenol‐absorbing compounds) prior to heating. A similar effect could be obtained by treating strawberry extracts with apricot tissue prior to heating but the mechanism whereby this was achieved is not clear. The bimodal inactivation was maintained after purification of the endo‐PGs by ammonium sulphate precipitation, DEAE‐cellulose and Sephadex G‐100 chromatography which also removed any detectable protease activity. It is suggested, therefore, that inactivation at 50–60°C is not caused by proteolytic activity but is due to conformational changes known to occur in proteins at about 55 °C.