bluuebunny/crossref_metadata_2025_split huggingface dataset:
The use of palm oil in aquaculture feeds for salmonid species
Authors: Ng Wing‐Keong , Tocher Douglas R. , Bell J. Gordon 
Published: March 2007

AbstractIn this overview, our current knowledge and research being conducted on the use of palm oil in the commercial feeds for cold‐water salmonid species such as Atlantic salmon and rainbow trout will be highlighted. Salmonid diets have a high lipid content to provide a source of easily available energy and also n‐3 polyunsaturated fatty acids (PUFA) which is used to maintain membrane fluidity in a cold‐water environment. The culture of salmonid fishes has traditionally depended on marine fish oils for this purpose, but with limited supplies and the rapid increase in salmon production, alternatives to fish oils must be investigated. Research has shown that crude palm oil can be used to replace 100% of added fish oils in salmonid diets without compromising growth performance and feed utilization efficiency, despite reductions in lipid and fatty acid digestibilities that occur during low water temperatures over the winter rearing period. Fatty acid desaturation and elongation activities increased with increasing dietary palm oil and, to a certain extent, decreasing water temperatures. The effects of palm oil on fish health requires further research, but the use of this more saturated vegetable oil may reduce oxidative stress in fish, thereby reducing pathological conditions associated with this physiological state. It is generally known that the fish fillet fatty acid composition directly reflects that of the dietary oil used. Extrapolating from work done with other vegetable oils, the supply of beneficial n‐3 PUFA in salmon fillets to the human consumer can be maintained by using a finishing diet strategy just prior to harvesting, despite significant reductions in these fatty acids when high levels of dietary palm oil are used in grower feeds. Compared to vegetable oils such as soybean or rapeseed oil, palm oil has several advantages in terms of high oil productivity, lower cost, less deposition of undesirable fatty acids such as 18:2(n‐6), superior energy source in the form of saturated and monounsaturated fatty acids, and a high content of natural antioxidants (carotenes and vitamin E). Fillet texture and color were not affected by feeding salmon palm oil‐based diets.
Future prospects for oil palm in the 21st century: Biological and related challenges
Authors: Murphy Denis J. 
Published: March 2007

AbstractOil palm is currently at a historic crossroads as regards its future prospects as a versatile global oil crop. In 2005, oil palm became the world's leading commercial source of vegetable oil, and the continued expansion of Asian economies augers well for further growth in production. There are several significant challenges that face the oil palm industry, both biological and non‐biological. The major biological and managerial challenge will be to tackle the stagnating yield that has characterised average plantation output over the past decade. Yield can be enhanced by developing and efficiently propagating/distributing improved germplasm for both large plantations and smallholders. Improved biocontrol of major pests and diseases, such as Ganoderma and rhinoceros beetle, will also have a significant impact. Oil quality can be improved by diversifying fatty acid composition to produce high‐oleate varieties for mainstream edible/oleochemical use, as well as other useful acyl compositions, including nutraceutical components and enhanced vitamin A and E contents for higher‐value niche markets. The whole spectrum of breeding approaches, from DNA marker‐assisted selection to genetic engineering, is being deployed to meet these objectives. One of the potential threats to the future growth of oil palm as a source of high‐quality foods and oleochemicals is the rapid emergence of biodiesel, which might destabilise the industry in the short term and adversely impact on its image and attractiveness for longer‐term investment.
Evaluation of virgin olive oil bitterness by total phenol content analysis
Authors: Beltrán Gabriel , Ruano María T. , Jiménez Antonio , Uceda Marino , Aguilera María P. 
Published: March 2007

AbstractBitterness is an important sensory attribute of virgin olive oil (VOO). It is usually assessed by tasting, which is a time‐consuming method and needs trained tasters. Bitterness is related to the phenolic compounds and can be estimated by the measurement of the specific absorbance at 225 nm (K225). This paper proposes to evaluate oil bitterness intensity as estimated from the K225 values measuring the phenol content. A significant relationship between phenol content and K225 as well as a prediction model for bitterness intensity estimation from the phenol content was obtained. Classification of oil bitterness was based on the phenol content. Furthermore, when 12 VOO samples were classified by their bitterness intensities as estimated by the prediction model and by sensory analysis, more than 92% of the oil samples were correctly classified. Therefore, by measuring the phenol content, the bitterness intensity can be estimated and oils can be classified by their bitterness. This model may represent an easy method to evaluate the bitterness intensity without any sensory assessment.
Liquid‐liquid phase separation in acetone solutions of palm olein: Implications for solvent fractionation
Authors: Smith Kevin W. , Cain Fred W. , Favre Loek , Talbot Geoff 
Published: March 2007

AbstractThe quality of palm mid fractions (PMF) obtained by dry fractionation has increased, but the best‐quality PMF for application in many confectionery fats are still produced by solvent fractionation. In the present study, liquid‐liquid phase separation has been observed in acetone solutions both for pure triacylglycerols and for palm olein. The temperature at which phase separation occurs increases as the oil concentration is increased and linearly as the water content of the system is increased. The triacylglycerol compositions of the two liquid phases that form do not differ. However, the oil‐rich phase is depleted with respect to the polar components. The temperature at which liquid‐liquid phase separation occurs is reduced by about 0.2 and 0.4 °C per percent of free fatty acids and diacylglycerols, respectively. When oil‐rich droplets appear, crystallisation occurs within them rather than in the oil‐depleted phase, due to the higher oil concentration. Thus, liquid‐liquid phase separation prior to crystallisation raises the nucleation temperature but may lead to a greater concentration of entrained olein in the filter cake, leading to a poorer‐quality PMF.
Thermal and structural behaviour of crude palm oil: Crystallisation at very slow cooling rate
Authors: Chong Chiew Let , Kamarudin Zukarinah , Lesieur Pierre , Marangoni Alejandro , Bourgaux Claudie , Ollivon Michel 
Published: March 2007

AbstractThe crystallisation behaviour of crude palm oil (CPO) has been examined with a new instrument coupling time‐resolved synchrotron X‐ray diffraction with high‐sensitivity differential scanning calorimetry at cooling rates of 0.1 and 0.4 °C/min from melt temperature to –20 °C, in order to determine the triacylglycerol (TAG) organisations formed as a function of temperature and thermal treatment. At slow cooling rate, CPO TAG sequentially crystallise in apparently two different lamellar structures with double‐chain length of 41.9 Å and a triple‐chain length of 62.8Å stackings of β' type, which are correlated to two main exothermic peaks at 26 and 8 °C, respectively. While a time‐dependent slow β'→β irreversible transition is observed even at low temperature, it only affects a few percent of the TAG population. Subsequent heating at 1 °C/min showed no structural rearrangements of the crystalline forms observed before final melting, indicating that the main moiety of the system is close to equilibrium. Crystallisation at 0.4 °C/min has shown the formation of many additional structures, some of which are evanescent. An unexpected finding was the vicinity of the two lines corresponding to the two 2L (bilayered) structures and the isosbestic point located at 4.42 Å. Only careful analysis allowed the separation of both lines, the coexistence of which was related to the epitaxy/eutectic phenomenon, as evidenced by the simultaneous appearance of the 3L (trilayered) stackings at the same time of the second burst of the 2L stacking and the observation of the isosbestic point. The coexistence of β and β' forms even at high temperature demonstrates that the whole system is not in a two‐phase domain but rather in a three‐phase one (β + β' + liquid) in which all TAG molecules could not fit into a single β' structure. This is likely related with the granular phase separations observed in margarine.
CIEF with hydrodynamic and chemical mobilization for the separation of forms of α‐1‐acid glycoprotein
Authors: Lacunza Izaskun , Diez‐Masa Jose C. , de Frutos Mercedes 
Published: March 2007

Abstractα‐1‐Acid glycoprotein (AGP) is a protein that exists in different forms, which is due to variations in the amino acid sequence and/or in the glycosidic part of the protein. These differences confer to these forms, among other characteristics, diverse pIs. Changes in these forms of AGP have been correlated to modifications of the pathophysiological conditions of the individuals. One of the analytical techniques employed for their study has been IEF performed in slab gels. CIEF method with hydrodynamic and chemical mobilization, involving an isotachophoretic process, is developed in this work to separate up to 12 bands of forms of standard AGP, which is proposed as a more reproducible, quantitative, less sample‐consuming, and more automated one than conventional IEF. The challenge of this work has been the development of a CIEF method for the separation of bands of a very acidic protein (pI range: 1.8–3.8) in a capillary. Intraday RSD values ≤ 1.7% have been achieved for the relative migration time of the AGP bands to that of an internal standard. For intraday area precision, RSD (%) in the range of 2.70–22.71% for AGP zones accounting for more than 10% of total area of AGP sample has been obtained. As a proof of the potential of the methodology proposed, an AGP sample purified from a pool of sera of patients suffering from ovary cancer is analyzed by CIEF.
Electrophoretic separation of environmentally important phenolic compounds using montomorillonite‐coated fused‐silica capillaries
Authors: Mora Maria F. , García Carlos D. 
Published: March 2007

AbstractThis paper reports a simple procedure for coating fused‐silica capillaries with poly(diallyldimethyl ammonium chloride) and montmorillonite. The coated capillaries were characterized by performing EOF measurements as a function of buffer pH, number of layers of coating, and number of runs (stability). The coated capillaries showed a highly stable μEOF (run‐to‐run RSD less than 1.5%, n = 20), allowing continuous use for several days without conditioning. The coated capillaries were then used for the effective separation of nine environmentally important phenolic compounds showing a significant improvement in the resolution, when compared to bare fused‐silica capillaries. The EOF of the coated capillaries was constant in alkaline solutions (pH ≥ 7), allowing the optimization of the separation conditions of phenolic compounds without significantly affecting the μEOF.
A sheathless poly(methyl methacrylate) chip‐CE/MS interface fabricated using a wire‐assisted epoxy‐fixing method
Authors: Li Fu‐An , Wang Chih‐Hung , Her Guor‐Rong 
Published: March 2007

AbstractUsing a wire‐assisted epoxy‐fixing method, a sheathless CE/MS interface on a poly‐(methyl methacrylate) (PMMA) CE chip has been developed. The sheathless chip‐CE/MS interface utilized a tapered fused‐silica tip and the electrical connection was achieved through a layered coating of conductive rubber. The wire‐assisted method provided facile alignment of channels between the PMMA CE chip and an external capillary sprayer without the need for micromachining. Because the wire was in the channel during fixing, the risk of channel blockage by the epoxy was avoided. This chip CE device has minimal dead volume because the interstitial spaces were filled by a fast‐fixing epoxy resin. The performance of the chip‐CE‐ESI‐MS device was demonstrated with the analysis of peptide mixtures.
Parallel separation of multiple samples with negative pressure sample injection on a 3‐D microfluidic array chip
Authors: Zhang Lei , Yin Xuefeng 
Published: March 2007

AbstractA simple and powerful microfluidic array chip‐based electrophoresis system, which is composed of a 3‐D microfluidic array chip, a microvacuum pump‐based negative pressure sampling device, a high‐voltage supply and an LIF detector, was developed. The 3‐D microfluidic array chip was fabricated with three glass plates, in which a common sample waste bus (SWbus) was etched in the bottom layer plate to avoid intersecting with the separation channel array. The negative pressure sampling device consists of a microvacuum air pump, a buffer vessel, a 3‐way electromagnet valve, and a vacuum gauge. In the sample loading step, all the six samples and buffer solutions were drawn from their reservoirs across the injection intersections through the SWbus toward the common sample waste reservoir (SWT) by negative pressure. Only 0.5 s was required to obtain six pinched sample plugs at the channel crossings. By switching the three‐way electromagnetic valve to release the vacuum in the reservoir SWT, six sample plugs were simultaneously injected into the separation channels by EOF and electrophoretic separation was activated. Parallel separations of different analytes are presented on the 3‐D array chip by using the newly developed sampling device.
Separation of fluorescent phosphatidyl inositol phosphates by CE
Authors: Mwongela Simon M. , Lee Katherine , Sims Christopher E. , Allbritton Nancy L. 
Published: March 2007

AbstractPhosphatidyl inositol 4,5‐bisphosphate (PIP2) and phosphatidyl inositol 3,4,5‐trisphosphate (PIP3) labeled with 4,4‐difluoro‐5,7‐dimethyl‐4‐bora‐3a,4a‐diaza‐s‐indacene‐3‐propionic acid (BODIPY FL) on the acyl chain or a phosphatidyl ethanolamine head group were separated by CE with LIF detection. Several methods and capillary‐coating procedures were tested for the separation of these phosphatidyl inositol phosphates (PIPs) at 20°C. Separation of the PIPs in less than 20 min with excellent resolution was achieved using a buffer containing sodium deoxycholate (SDC), 1‐propanol, MgCl2 and the polymer coating reagent, EOTrol™ LR. The efficiency of the optimized method was as high as 1.3×105 plates. The dependence of the separation on the concentration of 1‐propanol, SDC, and MgCl2 was determined. The separation of PIP2 and PIP3 was primarily due to differential binding of the lipids to Mg2+ rather than to different solubilities in the micellar phase. The role of the SDC was to prevent adsorption of the hydrophobic lipids to the capillary wall and thus enhance the efficiency. The fluorescent PIPs are of value for both in vitro and in vivo assays of phospholipid metabolism. In particular, the use of these lipids with the optimized capillary‐based separation will be of utility for drug screening as well as cell‐based assays.
3′‐azido‐3′‐deoxythymidine induces deletions in L5178Y mouse lymphoma cells
Authors: Wang Jianyong , Chen Tao , Honma Masamitsu , Chen Ling , Moore Martha M. 
Published: March 2007

Abstract3′‐Azido‐3′‐deoxythymidine (AZT), a nucleoside analogue used for the treatment of acquired immunodeficiency syndrome (AIDS), induced a significant dose‐related increase in the thymidine kinase (Tk) mutant frequency (MF) in L5178Y/Tk+/− 3.7.2C mouse lymphoma cells. Treatment with 1 mg/ml (3,742 μM) AZT for 24 hr resulted in a MF of 407 × 10−6 compared to a control MF of 84 × 10−6. The MFs of the large and small colony mutants resulting from AZT exposure were 142 × 10−6 and 265 × 10−6, respectively. One hundred and fifty mutants from the 1 mg/ml (3,742 μM) AZT‐treated culture and sixty‐nine mutants from independent untreated cultures were isolated and analyzed. LOH analysis using a heteromorphic microsatellite locus located in the Tk gene was performed to determine the presence or absence of the Tk+ allele. Eight other microsatellite markers spanning the entire mouse chromosome 11 also were examined for heterozygosity to determine the extent of LOH. In addition, Tk gene dosage analysis was conducted using Real‐Time PCR in those mutants showing LOH at the Tk locus. The presence of only one Tk allele based on Real‐Time PCR indicated that the mutant resulted from deletion while the presence of two alleles was consistent with a recombination event. More mutants from the AZT‐treated culture showed Tk LOH than did independent mutants from the untreated cultures (91% vs. 64%) and the induced mutants also showed distinct chromosome 11 LOH patterns. The mutation spectrum of mutants from AZT‐treated cells was also significantly different from that of spontaneous mutants. More deletions and fewer intragenic mutations were observed in the mutants from the AZT‐treated culture than independent mutants from the untreated control. Our data indicate that AZT primarily induced LOH mutations in L5178Y mouse lymphoma cells and a large number of LOH mutations resulted from deletions. Environ. Mol. Mutagen., 2007. Published 2007 Wiley‐Liss, Inc.
Mutagenicity of zidovudine, lamivudine, and abacavir following in vitro exposure of human lymphoblastoid cells or in utero exposure of CD‐1 mice to single agents or drug combinations
Authors: Torres Salina M. , Walker Dale M. , Carter Meghan M. , Cook Dennis L. , McCash Consuelo L. , Cordova Edmund M. , Olivero Ofelia A. , Poirier Miriam C. , Walker Vernon E. 
Published: March 2007

AbstractExperiments were performed to investigate the impact of zidovudine (AZT), lamivudine (3TC), and abacavir (ABC) on cell survival and mutagenicity in two reporter genes, hypoxanthine‐guanine phosphoribosyltransferase (HPRT) and thymidine kinase (TK), using cell cloning assays for assessing the effects of individual drugs/drug combinations in (1) TK6 human lymphoblastoid cells exposed in vitro and (2) splenic lymphocytes from male CD‐1 mice exposed transplacentally on days 12–18 of gestation. In TK6 cells, dose‐related increases in HPRT and TK mutant frequencies were found following 3 days of exposure to AZT or 3TC alone (33, 100, or 300 μM), or to equimolar amounts of AZT‐3TC. Compared with single drug exposures, AZT‐3TC coexposures generally yielded enhanced elevations in HPRT and TK mutant frequencies. Mutagenicity experiments with ABC alone, or in combination with AZT‐3TC, were complicated by the extreme cytotoxicity of ABC. Exposure of cells either to relatively high levels of AZT‐3TC short‐term (100 μM, 3 days), or to peak plasma‐equivalent levels of AZT‐3TC for an extended period (10 μM, 30 days), resulted in similar drug‐induced mutagenic responses. Among sets of mice necropsied on days 13, 15, or 21 postpartum, Hprt mutant frequencies in T‐cells were significantly elevated in the AZT‐only (200 mg/kg bw/day) and AZT‐3TC (200 mg AZT + 100 mg 3TC/kg bw/day) groups at 13 days of age. These results suggest that the mutagenicity by these nucleoside analogs is driven by cumulative dose, and raises the question of whether AZT‐3TC has greater mutagenic effects than AZT alone in perinatally exposed children. Environ. Mol. Mutagen. © 2007 Wiley‐Liss, Inc.
Frequency of Hprt mutant lymphocytes and micronucleated erythrocytes in p53‐haplodeficient mice treated perinatally with AZT and AZT in combination with 3TC
Authors: Dobrovolsky Vasily N. , Shaddock Joseph G. , Mittelstaedt Roberta A. , Bishop Michelle E. , Lewis Sherry M. , Lee Fei W. , Aidoo Anane , Leakey Julian E.A. , Dunnick June K. , Heflich Robert H. 
Published: March 2007

AbstractAzidothymidine (AZT) is a nucleoside reverse transcriptase inhibitor (NRTI) that is used for reducing mother‐to‐child transmission of human immunodeficiency virus I. Combinations of AZT and 3′‐thiacytidine (3TC) are even more effective than AZT alone. AZT, however, is a mutagen and carcinogen in rodent models and 3TC can increase the genotoxicity of AZT. Since p53 plays a key role in human and mouse tumorigenesis, p53‐haplodeficient mice are currently being evaluated as a model for assessing the carcinogenicity of perinatal exposure to NRTIs. In the present study, male C57BL/6 p53+/+ and p53−/− mice were mated with C3H p53+/+ females; the pregnant females were treated on gestation day 12 through parturition with 40, 80, and 160 mg/kg of AZT or a combination of 160 mg/kg AZT and 100 mg/kg 3TC (AZT‐3TC); the p53+/+ and p53+/− offspring were treated daily after birth through postnatal day (PND) 28. The frequencies of micronucleated reticulocytes (MN‐RETs) and micronucleated normochromatic erythrocytes (MN‐NCEs) were determined on PND1, PND10, and PND28; the frequency of Hprt mutant lymphocytes was measured on PND28. The frequencies of MN‐RETs and MN‐NCEs were increased in treated animals at all time points; there were no differences in the responses of p53+/+ and p53+/− animals treated with identical doses of NRTIs. After correction for clonal expansion, both AZT and AZT‐3TC treatments induced small but significant increases in the frequency of Hprt mutant lymphocytes in p53+/− mice, but not in p53+/+ mice. The data indicate that p53 haplodeficiency affects the genotoxicity of NRTIs; thus, p53+/− mice may be a sensitive model for evaluating the carcinogenicity of perinatal exposure to NRTIs. Environ. Mol. Mutagen., 2007. Published 2007 Wiley‐Liss, Inc.
Relative mutagenic potencies of several nucleoside analogs, alone or in drug pairs, at the HPRT and TK loci of human TK6 lymphoblastoid cells
Authors: Carter Meghan M. , Torres Salina M. , Cook Dennis L. , McCash Consuelo L. , Yu Mia , Walker Vernon E. , Walker Dale M. 
Published: March 2007

AbstractExperiments were performed to investigate the impact of didanosine (ddI), lamivudine (3TC), and stavudine (d4T) on cell survival and mutagenicity in two reporter genes, hypoxanthine‐guanine phosphoribosyltransferase (HPRT) and thymidine kinase (TK), using a cell cloning assay for assessing the effects of individual nucleoside analogs (NRTIs)/drug combinations in human TK6 B‐lymphoblastoid cells. Three‐day treatments with 0, 33, 100, or 300 μM ddI, 3TC, or ddI‐3TC produced positive trends for increased HPRT and TK mutant frequencies. While dose‐related trends were too small to reach significance after treatments with d4T or d4T‐3TC, pairwise comparisons with control cells indicated that exposure to 100 μM d4T or d4T‐3TC caused significant elevations in HPRT mutants. Measurements of mutagenicity in cells exposed to d4T (or d4T‐3TC) were complicated by the cytotoxicity of this NRTI. Enhanced increases in mutagenic responses to combined NRTI treatments, compared with single drug treatments, occurred as additive to synergistic effects in the HPRT gene of cells exposed to 100 μM ddI‐3TC or 100 μM d4T‐3TC, and in the TK gene of cells exposed to 100 or 300 μM ddI‐3TC. Comparisons of these data to mutagenicity studies of other NRTIs in the same system (Meng Q et al. [2000c]: Proc Natl Acad Sci USA 97:12667–126671; Torres SM et al. [2007]: Environ Mol Mutagen) indicate that the relative mutagenic potencies for all drugs tested to date are: AZT‐ddI > ddI‐3TC > AZT‐3TC ≅ AZT‐3TC‐ABC (abacavir) > AZT ≥ddI > d4T‐3TC > 3TC > d4T ≥ ABC. These collective data suggest that all NRTIs with antiviral activity against HIV‐1 may cause host cell DNA damage and mutations, and impose a cancer risk. Environ. Mol. Mutagen., 2007. © 2007 Wiley‐Liss, Inc.