bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of complement in neutralization of respiratory syncytial virus
Authors: Yoder Sandra M. , Zhu Yuwei , Ikizler Mine R. , Wright Peter F. 
Published: February 2004

AbstractSerum neutralizing antibody titers to respiratory syncytial virus (RSV) are higher when assayed with guinea pig complement. A number of different mechanisms have been suggested for enhancement of neutralization by complement. The most straightforward is that complement–antibody complexes present a greater steric hindrance to viral entry than with antibody alone. To define the implications of measuring serum neutralizing antibody with and without complement, sera from adults, young children, infants, and cord bloods were run in plaque neutralization assays with representative viruses of the RSV A and B subgroups. Although titers of neutralizing antibody were higher in the presence of complement, the addition of complement did not increase the ability to detect antibody rises after natural infection. Some of the complement effect may be attributable to an inhibition of RSV replication by complement alone. While these observations do not address the role for complement in the pathogenesis of RSV infection, they suggest that neutralization assays performed without complement may be most reflective of physiologic conditions in the respiratory tract. J. Med. Virol. 72:688–694, 2004. © 2004 Wiley‐Liss, Inc.
Reversal of toxigenic effects of aflatoxin B1on cockerels by alcoholic extract of African nutmeg,Monodora myristica
Authors: Oluwafemi Flora , Taiwo Victor O 
Published: February 2004

AbstractThe reversal of the toxigenic effects of crystalline aflatoxin B1(AFB1; fromAspergilus flavus) on cockerels using different concentrations of the ethanolic extract from the seeds of African nutmeg,Monodora myristica, was studied in 130 two‐week‐old cockerels, randomly divided into 13 groups (A–M) of ten birds each. Group A (controls) received 100 µl of phosphate‐buffered saline, while those in the test groups B, C and D received 690 ng, 1380 ng or 2010 ng of AFB1, respectively; groups E to M received the three doses of AFB1with either 0.1, 0.2 or 0.3 ml of the extract ofM myristica, respectively, 5 min after administration of AFB1. Jugular blood, collected on days 14 and 21 after administration, was analysed for haematology parameters, serum proteins, alanine aminotransaminase (ALT), aspartate aminotransaminase (AST) and γ‐glutamyl transferase (GGT) levels. The birds were observed daily for clinical signs and mortality for 21 days. Post‐mortem examination was carried out on the livers of dead birds and those sacrificed by exsanguination after the 21 days post‐administration. One hundred per cent mortality was recorded in cockerels that received high doses of only AFB1within 72 h (2010 ng per bird), and between 17 and 19 days (1380 ng). The cockerels developed leucocytosis and microcytic hypochromic anaemia. Dosing with 0.2 or 0.3 ml of the extract ofM myristicareversed these changes over time, while the lowest dose (0.1 ml) did not. While serum bilirubin levels rose significantly in test cockerels, no significant changes (P> 0.05) were observed in the levels of serum proteins of control and test cockerels, whether or not they received the extract ofM myristica. Aflatoxicosis caused significant decreases and increases (P< 0.05) in serum AST and GGT levels, respectively, while the administration of alcoholic extract ofM myristicareversed the GGT but not AST levels to normal. Livers from control cockerels and those given 2010 ng of AFB1showed no appreciable gross or histological lesions. The other groups showed mild to moderate hepatomegaly, paleness and friability, diffuse vacuolar degeneration and necrosis, Kupffer cell proliferation, presence of megalocytes and multinucleated hepatocytes. Cockerels that received 0.2 or 0.3 ml of extract ofM myristica, irrespective of the dose of AFB1showed the mildest hepatic lesions. The results of this study show that AFB1is highly toxigenic to cockerels and that this could be successfully reversed by the concurrent administration of alcoholic extract ofM myristica. It is therefore recommended that reduction of fungal growth on foods and subsequent toxicosis by aeration, cooling, modified atmospheres or by fungistats, is complemented with the use of extracts of spices fromM myristicaseed, a tree widely distributed along the west coast and central Africa. Copyright © 2004 Society of Chemical Industry
Copper bioavailability in rats fed unused palm olein and palm olein used in frying
Authors: Pérez‐Granados Ana M , Vaquero M Pilar , Navarro M Pilar 
Published: February 2004

AbstractThe influence of the consumption of unused and used (in repeated potato frying operations) palm olein on copper bioavailability was investigated. Three diets containing respectively 8% olive oil (O), palm olein (P) and palm olein from 80 repeated potato frying operation without turnover (PF), which nearly reached the limit of 25% polar compounds allowed by law, were given to rats for 28 days. No differences were found in food intake and body weight. The liver mass index was higher in PF than in P rats. No significant differences were observed in copper apparent absorption or in liver, skin, erythrocyte, serum and carcass copper contents. Therefore consumption of palm olein, whether unused or used in frying, does not alter copper bioavailability in growing rats. Copyright © 2004 Society of Chemical Industry
Changes in carotenoids and chlorophylls in fresh green asparagus (Asparagus officinalis L) stored under modified atmosphere packaging
Authors: Tenorio MD , Villanueva MJ , Sagardoy M 
Published: February 2004

AbstractAsparagus is a highly perishable product owing to its high respiratory rate, a reason why modified atmosphere packaging (MAP) has been used in order to increase the shelf‐life of fresh asparagus. Carotenoid and chlorophyll pigments are important compounds for the maintenance of both the nutritional and sensory quality of asparagus. In this study, green asparagus spears were stored under refrigeration at 2 °C for 14 days, under MAP at 2 °C for 26–33 days and under MAP at 10 °C for 20 days. Pigment profiles were determined using high‐performance liquid chromatography (HPLC), with three classes of compounds being detected, namely oxygenated carotenoids (xanthophylls), hydrocarbonated carotenoids (carotenes) and chlorophylls. The xanthophylls identified were neoxanthin, violaxanthin, lutein and zeaxanthin. Only β‐carotene was detected in the carotene fraction. In the chlorophyll pigments, three molecules were isolated, chlorophyll b, its epimer chlorophyll b′ and chlorophyll a. Also detected were the first degradation products of chlorophylls, pheophytins b and a respectively. Modified atmosphere packaging at 2 °C was found to be effective in extending the shelf‐life for up to 4 weeks and in preserving the colour of fresh asparagus. Copyright © 2004 Society of Chemical Industry
Bunker‐stored silage covered with biodegradable coating. Part I. Laboratory assay
Authors: Denoncourt Patrick , Caillet Stéphane , Lacroix Monique 
Published: February 2004

AbstractThe effect of a hydrophobic biodegradable coating on the conservation of silage was evaluated in comparison with unsealed silage and silage covered with a polyethylene (plastic). Silage samples were subjected to biochemical analysis (pH, dry matter, water‐soluble sugars, ammoniacal nitrogen, lactic acid) and microbiological analysis (total aerobes, lactic acid bacteria, moulds and yeasts) during 135 days of storage. Silage covered with the biodegradable coating had a constant pH value of 4.79 and was preserved against spoilage until day 120, whereas the pH of unsealed silage increased during the first 6 days to a value of 8.22. After 2 months of storage, silage covered with the biodegradable coating had a lower dry matter content, higher water‐soluble sugar content and higher lactic acid concentration than unsealed silage. During storage the population of total aerobes was lower in silage covered with the biodegradable coating than in silage covered with plastic. Furthermore, silage covered with the biodegradable coating had a stable content of aerobic micro‐organisms. The biodegradable‐coated silage showed a growth of lactic acid bacteria similar to that of silage covered with plastic. Only silage covered with the biodegradable coating had a low initial content of moulds and yeasts. Air infiltration was present throughout the storage period in the plastic and biodegradable coating treatments and was linked with the degradation of silage in both cases. However, the biodegradable coating significantly (P ≤ 0.05) increased the period of silage conservation compared with that of uncoated silage. Copyright © 2004 Society of Chemical Industry
Vitamin E levels, thiobarbituric acid test and sensory evaluation of breast muscles from broilers fed α‐tocopheryl acetate‐ and β‐carotene‐supplemented diets
Authors: Carreras Irene , Guerrero Luis , Guàrdia MD , Esteve‐Garcia Enric , García Regueiro JA , Sárraga Carmen 
Published: February 2004

AbstractThe objective of this study was to investigate the effect of dietary α‐tocopheryl acetate and β‐carotene supplementation on lipid oxidation of breast meat from broilers fed lard as the fat source. Supplementation of broilers with 100 mg kg−1 α‐tocopheryl acetate increased the vitamin E levels in raw breast samples significantly (p < 0.05), whereas the presence of 1.5 mg kg−1 dietary β‐carotene tended to decrease vitamin E deposition. The presence of vitamin E delayed lipid oxidation significantly, but thiobarbituric acid values of samples from broilers fed the β‐carotene‐supplemented diet did not differ from those of control samples. Vitamin E reduced sensory meat rancidity, whilst vitamin E, β‐carotene and their combination modified meat texture. The results show the effectiveness of dietary α‐tocopheryl acetate supplementation in protecting broiler meat against lipid oxidation. Copyright © 2004 Society of Chemical Industry
The Cannizzaro‐like metabolites of secoiridoid glucosides in some olive cultivars
Authors: Piperno Anna , Toscano Marirosa , Uccella Nicola A 
Published: February 2004

AbstractOleuropein (the most abundant bitter principle) and its analogue ligstroside, both secoiridoid biophenols, were extracted from Hojiblanca black olives and analysed by preparative flash chromatography and HPLC. During olive growth, maturation and processing, these compounds undergo biological and technological degradation to various metabolites, by enzymatic degradation through esterases, phenoloxidases and β‐glucosidases. An enzymatic system with regiospecific Cannizzaro‐like activity could be responsible for two novel metabolites, isolated and characterised by 1H‐ NMR, 12C NMR and FAB‐MS as hydroxycarboxylic and lactone derivatives of terpenoid origin from the precursor oleoside‐11‐methylester, formed from both secoiridoid biophenols. The occurrence of these two secoiridoid metabolites requires a thermodynamically controlled sequential process, via hydride rearrangements, through the complex metabolic pathway. The possible reaction sequence was interpreted by molecular calculations performed on competitive isomers. Copyright © 2004 Society of Chemical Industry
Condensed tannins in humid tropical fodder crops and their in vitro biological activity: Part 1
Authors: López Juan , Tejada Irma , Vásquez Carlos , Garza Juan de Dios , Shimada Armando 
Published: February 2004

AbstractA descriptive study was conducted in order to determine the tannin profiles of tropical fodder crops. The following types of condensed tannins (CT) were determined (expressed as g kg−1 of dry matter): free (FCT), bound to protein (CTP), bound to fibre (CTF) and total (TCT). High FCT levels were found in Desmodium ovalifolium (228.4), Flemigia macrophylla (181.9), Guazuma ulmyfolia (129.7) and Leucaena leucocephala (129.5). The highest concentrations of CTP were detected in Gliricidia sepium (61.0), F macrophylla (23.3), and G ulmyfolia (21.1). CTF levels were the highest in G ulmyfolia (55.1), F macrophylla (46.7) and G sepium (41.5). Analyzed samples cultivated in vertisol and fluvisol soils showed different contents of tannins. It has been reported that plants with more than 60 g kg−1 FCT are less palatable and digestible than forages with lower concentrations of this chemical class, although there is more protein to bypass the rumen and higher nitrogen retention. Graminaceous plants showed higher concentrations of FCT and TCT concentrations were generally lower than legumes and other forage crops. Copyright © 2004 Society of Chemical Industry
Examination of the sulfur dioxide–ascorbic acid anti‐oxidant system in a model white wine matrix
Authors: Bradshaw Mark P , Scollary Geoffrey R , Prenzler Paul D 
Published: February 2004

AbstractThe effectiveness of sulfur dioxide in inhibiting the ascorbic acid induced oxidation of (+)‐catechin in a matrix simulating white wine was investigated. At a sulfur dioxide:ascorbic acid mole ratio of 0.8:1.0, sulfur dioxide extended the delay prior to the onset of (+)‐catechin browning as measured by the increase in absorbance at 440 nm from 2 to 4 days post reaction initiation. The lengthening of the pre‐browning period was correlated with an increase in the time required to oxidise ascorbic acid completely, the sequence of events being loss of sulfur dioxide (day 3), loss of ascorbic acid (day 4) and on‐set of (+)‐catechin browning (day 4). Increasing the sulfur dioxide to ascorbic acid mole ratio to 3.0:1.0 inhibited the onset of (+)‐catechin browning over the 14‐day reaction period. This inhibition was achieved at considerable cost to the sulfur dioxide concentration, with the ratio of sulfur dioxide consumed to ascorbic acid oxidised being 1.7 compared with the expected fraction of 1.0. Reasons for the enhanced consumption of sulfur dioxide and the implications of this study for maintenance of quality in white wine production are discussed. Copyright © 2004 Society of Chemical Industry
Condensed tannins in tropical fodder crops and their in vitro biological activity: Part 2
Authors: López Juan , Tejada Irma , Vásquez Carlos , Garza Juan de Dios , Shimada Armando 
Published: February 2004

AbstractWith the aim to evaluate the biological activity of purified condensed tannins of tropical forages we conducted two in vitro experiments. In the first, using a radial diffusion technique, the protein precipitation of free condensed tannins (FCT) from Manihot esculenta, leucaena leucocephala, Arachis pintoi, Guazuma ulmyfolia, Gliricidia sepium and of tannic acid on bovine serum albumin (ASB), papain, pepsin and trypsin at pH 5.0 and 6.8 was evaluated with a three‐way analysis of variance. Significant effects (P ≤ 0.05) for the tannin type, protein source, pH and their interactions were observed. Pepsin showed the highest protein precipitation (PP) at a pH of 5.0 (82.9 µg) with FCT of G ulmyfolia and the lowest (0 and 0.2 µg) of BSA with G sepium and A pintoi at pH 6.8. Experiments were then conducted using completely randomized designs in order to observe the effect of adding 0, 1.25 or 2.50 mg of FCT from M esculenta and L leucocephala to the rumen fluid‐buffer in an in vitro dry matter digestibility test (IVDMD) of Medicago sativa and Brachiaria decumbens, The IVDMD value of M sativa (757 g kg−1) decreased with L leucocephala tannins, although with those of M esculenta it was increased (824 g kg−1 and 871 g kg−1, respectively) for 1.25 and 2.5 mg of FCT. The IVDMD value of B decumbens (774 g kg−1 without tannins) diminished with any tannin and any dose (P < 0.05). We conclude that there are differences in the FCT contents of fodder crops and in their biological activity measured as the capacity to precipitate proteins, which is modified by the type of tannin, the protein and the pH. The result of an IVDMD is regulated by the type of tannin and its dose. Copyright © 2004 Society of Chemical Industry
Kinetics of peptide fraction release during in vitro digestion of casein
Authors: Agudelo Rafael A , Gauthier Sylvie F , Pouliot Yves , Marin Johanne , Savoie Laurent 
Published: February 2004

AbstractThe charges and sizes of peptides released during in vitro casein digestion were investigated. Casein was hydrolysed sequentially by pepsin and pancreatin and, during hydrolysis, the products of digestion were removed by dialysis. The undigested residues were separated by ion‐exchange chromatography into basic–neutral (BN), lightly acid (LA) and acid (A) fractions. Each of these fractions was further resolved by sequential ultrafiltration (MWCO 10 and 1 kDa) into two retentates (>10 and 10–1 kDa) and one permeate (<1 kDa). The polypeptides (>10 kDa) produced by pepsin hydrolysis were degraded into small molecules during the first 2 h of pancreatin hydrolysis; less than 100 mg g−1 of the total N remained undigested. Most of the material produced was in the BN10‐1 (ie basic–neutral, 10–1 kDa) fraction, with three times as much N as the A10‐1 fractions. As digestion progressed a decrease in the proportion of N in the residues retained by the dialysis membrane was observed. This decrease was particularly rapid in the BN10‐1 fraction. Large proportions of leucine (Leu), lysine (Lys), arginine (Arg), phenylalanine (Phe) and tyrosine (Tyr) were found as peptides smaller than 1 kDa, both in the dialysates and retentates, while glutamine (Glu), threonine (Thr), serine (Ser) and asparagine (Asp) appeared mostly in the A10‐1 and A > 10 fractions. After 6 h of pancreatin hydrolysis most of the proline (Pro) content was in the BN10‐1 fractions. The mechanisms behind and the implications of these results are discussed. Copyright © 2004 Society of Chemical Industry
Irradiation of maize and bean flours: effects on starch physicochemical properties
Authors: Rombo George O , Taylor John RN , Minnaar Amanda 
Published: February 2004

AbstractIn an earlier study (Rombo GO et al, J Sci Food Agric 81: 497–502 (2001)) it was found that the in vitro starch digestibility of raw and cooked maize and bean flours was increased by irradiation of the flours at 2.5 kGy, but there was a reduction in starch digestibility at doses above 2.5 kGy. Experiments were performed to determine what effects irradiation had on the molecular properties of the starch in maize and bean flours. Increasing irradiation dose caused an increased proportion of β(1–3)‐ and β(1–4)‐bonded starch in bean and maize flours. Starch containing β‐bonds is only partially digestible by porcine pancreatic α‐amylase, and this may in part explain the reduction in starch digestibility at higher doses. Size exclusion–high‐performance liquid chromatography showed that higher irradiation doses led to a reduction in the molecular size of amylopectin in both bean and maize starches, which presumably involved debranching and an increase in the production of short, straight‐chain molecules. With increased irradiation dose there was an increase in the crystallinity of the amylopectin fraction of the bean starch as shown by differential scanning calorimetry, presumably at least in part due to β‐bonding and amylopectin depolymerisation. These two factors and their interrelated effects are probably responsible for the observed slight reduction in maize and bean porridge starch digestibility reported previously. Copyright © 2004 Society of Chemical Industry
Furosine is a useful indicator in pre‐baked breads
Authors: Cardenas Ruiz Jonathan , Guerra‐Hernandez Eduardo , García‐Villanova Belén 
Published: February 2004

AbstractThere is increasing demand for pre‐baked bread. Bakers can meet consumer requirements for breads of specific flavour and colour by pre‐baking an amount of bread in the morning and completing the baking process in the afternoon. This type of product is of special interest to sandwich bars, restaurants and large communities. In order to obtain an indicator of utility to monitor the processing of pre‐baked bread, the browning indicators furosine, hydroxymethylfurfural (HMF) and glucosylisomaltol were analysed in two independent assays of bread pre‐baked at 175 °C for between 5 and 30 min. No furosine was detected in raw or fermented dough. In the pre‐baking stage, furosine increased from 1.5‐ to 5‐fold between 5 and 30 min. The furosine values obtained in the two independent experiments were similar. HMF and glucosylisomaltol were only detected after 15 min, which is the time period commonly used for processing by the industry. Thus, among these indicators, furosine is the only one with utility for monitoring the pre‐baking process. On the other hand, a study of the baking of pre‐baked bread at 220 °C showed that HMF and glucosylisomaltol can be used to monitor the latter process. Copyright © 2004 Society of Chemical Industry
Effect of gluten content on recrystallisation kinetics and water mobility in wheat starch gels
Authors: Wang Xin , Choi Sung‐Gil , Kerr William L 
Published: February 2004

AbstractThe effect of gluten on starch retrogradation at 5 °C was studied using 1H NMR relaxometry. Gels were made from gluten and starch at 27.8 and 38.5% total solids and with gluten comprising either 10, 15 or 20% of the solids. Changes in the transverse relaxation time constant (T2) were related to water mobility. Mono‐exponential analysis of relaxation curves showed that, in general, gluten retarded starch retrogradation. T2 values in gluten gels also decreased during storage, but to a much lesser extent. Distributed exponential analysis showed that two distinct regions of T2 were observed in all samples. During aging, the peak values of both regions shifted to lower values for all gels. Starch gel samples showed the most significant shift, and gluten gels showed the least. The three levels of gluten addition in starch/gluten gels produced similar shifts. For all samples the signal intensity of the less mobile region decreased more dramatically than that of the more mobile region during storage. It was suggested that gluten retards water loss in the granule remnants. Copyright © 2004 Society of Chemical Industry
Colour characteristics of honeys as influenced by pollen grain content: a multivariate study
Authors: Terrab Anass , Escudero M Luisa , González‐Miret M Lourdes , Heredia Francisco J 
Published: February 2004

AbstractA chromatic analysis by tristimulus colorimetry and a pollen analysis (pollen grains contained in each honey sample, considering their volume and geometrical shape) were carried out on 33 Eucalyptus unifloral honeys; the colour of the pollen grains was also considered. Multiple linear regression (MLR) and partial least squares regression (PLSR) were used to establish equations relating the chromatic variables to the pollen data, ie number and morphology of the pollen grains, thus allowing the prediction of the ultimate colour from the botanical characteristics. The results obtained show that lightness (L*) is significantly (p < 0.05) related to the pollen type Olea europaea; on the other hand, the variable that better relates to the chroma $(C_{ab}^{*})$ is the Zea mays pollen type. Copyright © 2004 Society of Chemical Industry