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Selected AbstractsStudies on thermoplastic polyurethanes based on new diphenylethane-derivative diols.JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008Abstract Two series of poly(ether urethane)s and one series of poly(ester urethane)s were synthesized, containing, respectively, poly(oxytetramethylene) diol (PTMO) of Mn = 1000 and 2000 and poly(,-caprolactone) diol of Mn = 2000 as soft segments. In each series the same hard segment, i.e., 4,4,-(ethane-1,2-diyl)bis(benzenethiohexanol)/hexane-1,6-diyl diisocyanate, with different content (, 14,72 wt %) was used. The polymers were prepared by a one-step melt polymerization in the presence of dibutyltin dilaurate as a catalyst, at the molar ratio of NCO/OH = 1 (in the case of the polymers from PTMO of Mn = 1000 also at 1.05). For all polymers structures (by FTIR and X-ray diffraction analysis) and physicochemical, thermal (by differential scanning calorimetry and thermogravimetric analysis), and tensile properties as well as Shore A/D hardness were determined. The resulting polymers were thermoplastic materials with partially crystalline structures (except the polymer with the highest content of PTMO of Mn = 2000). It was found that the poly(ether urethane)s showed lower crystallinity, glass-transition temperature (Tg), and hardness as well as better thermal stability than the poly(ester urethane)s. Poly(ether urethane)s also exhibited higher tensile strength (up to 23.5 MPa vs. 20.3 MPa) and elongation at break (up to , 1950% vs. 1200%) in comparison with the corresponding poly(ester urethane)s. Among the poly(ether urethane)s an increase in soft-segment length was accompanied by an increase in thermal stability, tensile strength, and elongation at break, as well as a decrease in Tg, crystallinity, and hardness. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Influence of oxidative stress and grains on sclerotial biomass and carotenoid yield of Penicillium sp.JOURNAL OF BASIC MICROBIOLOGY, Issue 4 2010Abstract Oxidative stress and grains were evaluated for carotenoid production by solid-state fermentation using Penicillium sp. PT95. When the fungus was grown at high oxidative stress, its sclerotial biomass and carotenoid content in sclerotia increased significantly with respect to low oxidative stress (P < 0.01). High oxidative stress also caused a statistically significant increase in carotenoid yield as compared with low oxidative stress (P < 0.01). Both the sclerotial biomass and the amount of carotenoid accumulated in sclerotia of strain PT95 were strongly dependent on the grain medium used. Among the grain media tested under high oxidative stress, buckwheat medium gave the highest content of carotenoid in sclerotia (828 ,g/g dry sclerotia), millet medium gave respectively the highest sclerotial biomass (12.69 g/100 g grain) and carotenoid yield (10.152 mg/100 g grain). (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Radical Scavenging Activity and Phenolic Compounds in Persimmon (Diospyros kaki L. cv. Mopan)JOURNAL OF FOOD SCIENCE, Issue 1 2008X.N. Chen ABSTRACT:, The Mopan persimmon (Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 ,m trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly (P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations (R2= 0.993, P < 0.05, ABTS radical; R2= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated (R2= 0.831, P < 0.05, ABTS radical; R2= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato. [source] Chemical Characterization of Liver Lipid and Protein from Cold-Water Fish SpeciesJOURNAL OF FOOD SCIENCE, Issue 6 2006Peter J. Bechtel ABSTRACT:, The largest US harvests of marine fish for human consumption are from Alaska waters. Livers from these fish are combined with other fish offal and made into fish meal and oil or discarded. The purpose of this study was to characterize liver lipids and proteins from important commercial species including walleye pollock (WP), pink salmon (PS), Pacific halibut (PH), flat head sole (FS), and spiny head rock fish (RF), and underutilized species including arrow tooth flounder (AF) and big mouth sculpin (BS). Liver lipid content ranged from 50.3% in WP to 3.3% in PS. Protein content ranged from 7.7% in WP to 18.4% in BS. PS livers had the highest content of ,-3 fatty acids at 336 mg/g of oil and AF had the lowest content at 110 mg/g of oil. There were significant differences in the content of 9 amino acids with methionine and lysine values ranging from 2.66% to 3.43% and 7.19% to 9.45% of the total amino acids, respectively. Protein from the cold water marine fish livers was of high quality and the oils contained substantial quantities of ,-3 fatty acids. Fish livers had distinct chemical properties and can be used for the development of unique food ingredients. [source] Changes in Progesterone Receptor Isoforms Content in the Rat Brain During the Oestrous Cycle and After Oestradiol and Progesterone TreatmentsJOURNAL OF NEUROENDOCRINOLOGY, Issue 10 2003C. Guerra-Araiza Abstract We studied the effects of oestradiol and progesterone on progesterone receptor (PR) isoform content in the brain of ovariectomized rats and in intact rats during the oestrous cycle by Western blot analysis. In the hypothalamus and the preoptic area of ovariectomized rats, PR-A and PR-B content was increased by oestradiol, whereas progesterone significantly diminished the content of both PR isoforms after 3 h of treatment in the hypothalamus, but not in the preoptic area. In the hippocampus, only PR-A content was significantly increased by oestradiol while progesterone significantly diminished it after 12 h of treatment. In the frontal cortex, no treatment significantly modified PR isoform content. During the oestrous cycle, the lowest content of PR isoforms in the hypothalamus was observed on diestrus day and, by contrast, in the preoptic area, the highest content of both PR isoforms was observed on diestrus day. We observed no changes in PR isoform content in the hippocampus during the oestrous cycle. These results indicate that the expression of PR isoforms is differentially regulated by sex steroid hormones in a regionally specific manner. [source] Expression of DPC4/Smad4 gene in stone-containing intrahepatic bile ductJOURNAL OF SURGICAL ONCOLOGY, Issue 4 2006King-Teh Lee MD Abstract Background and Objectives Hepatolithiasis is etiologically related to cholangiocarcinoma. We underwent this study with an attempt to examine the expression of DPC4/Smad4 gene in stone-containing intrahepatic bile ducts (IHD) and intrahepatic cholangiocarcinoma (ICC). Patients and Methods The immunohistochemical method and RT-PCR analysis were used to study the expression of DPC4/Smad4 gene in normal IHD, stone-containing IHD, and ICC. All the specimens were from hepatic resection. Results The immunohistochemical study showed that all specimens from 24 normal IHD had marked expression of DPC4/Smad4 gene, while there was 4.4% (2/46) and 33.3% (3/9) loss of DPC4/Smad4 expression in stone-containing IHD and ICC, respectively. Among the specimens of stone-containing IHD, all the hyperplastic epithelial cells showed normal expression of DPC4/Smad4 gene while dysplastic epithelial cells showed 20% (2/10) loss expression of DPC4/Smad4. The RT-PCR analysis showed that the normal IHD had the highest content of DPC4/Smad4 mRNA, which was threefold and sixfold higher than that of stone-containing IHD and ICC, respectively. Conclusion Loss expression of DPC4/Smad4 gene was found both in stone-containing IHD and ICC. Dysplastic epithelium of stone-containing IHD had higher potential for malignant transformation. J. Surg. Oncol. 2006;94:338,343. © 2006 Wiley-Liss, Inc. [source] Antioxidant compounds in green and red peppers as affected by irrigation frequency, salinity and nutrient solution compositionJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2009Alicia Marín Abstract BACKGROUND: There is a need to encourage more sustainable agricultural practices, reducing inputs of water and fertilisers while minimising any negative impact on fruit quality. The effect of irrigation frequency, salinity and potassium and calcium fertilisation on the content of bioactive compounds and quality attributes of green and red peppers grown with and without substrate was evaluated. RESULTS: Low irrigation frequency and salinity improved the quality attributes (dry matter, soluble solids content and titratable acidity) of pepper. Low irrigation frequency increased vitamin C content by 23% in green peppers, while in red fruits it was not affected. In contrast, total carotenoids and provitamin A only increased in red fruits by 30% and 15%, respectively, as a consequence of low irrigation frequency. When the effect of potassium and calcium doses was investigated, it was shown that a high proportion of potassium increased the vitamin C, provitamin A and total phenolic content of red and green peppers, whereas pepper grown at low calcium doses, presented the highest content in carotenoids and provitamin A. CONCLUSION: Low irrigation frequency and fertilisation with high potassium and low calcium doses improved pepper quality increasing the content of bioactive compounds. Copyright © 2009 Society of Chemical Industry [source] Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Mateja Colaric Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source] Superoxide dismutase content and fatty acid composition in subsets of human spermatozoa from normozoospermic, asthenozoospermic, and polyzoospermic semen samplesMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2003J. Calamera Abstract Human ejaculated sperm comprised discrete subsets of spermatozoa, with different degrees of maturation. These subpopulations can be isolated through density gradient centrifugation. Sperm from the lowest density layer show the highest content of docosahexaenoic acid and sterols, and produce the highest levels of reactive oxygen species. The main objective of this study was to determine the superoxide dismutase (SOD) content and fatty acid composition of subsets of spermatozoa isolated from normozoospermic, asthenozoospermic, and polyzoospermic semen samples. Four sperm fractions (1,4) were obtained using ISolate gradient centrifugation. Morphology, motion parameters, SOD content, and fatty acid composition were assessed in the original samples and their fractions. Overall, sperm from normozoospermic samples had higher SOD content than those of asthenozoospermic or polyzoospermic samples. Once fractionated in subsets, the sperm SOD content decreased significantly (P,<,0.0001) from fraction 1 (top) to 4 (bottom) in all three groups of samples. Fatty acid content as well as the oxidation coefficient followed the same pattern, decreasing from fraction 1 to 4 (F1,F4). Normo- and polyzoospermic samples showed similar amounts of fatty acids, while asthenozoospermic samples mostly revealed increased levels. Normozoospermic samples displayed the lowest unsaturated fatty acid (UFA)/SOD ratio. Spermatozoa from astheno- and polyzoospermic samples, two common seminal pathologies, showed higher UFA and lower SOD content than normal sperm, therefore exhibiting a higher susceptibility to peroxidative damage. F4 from all groups, containing the most mature spermatozoa, displayed the lowest polyunsaturated fatty acid and SOD content of all subsets, suggesting that excessive SOD activity as well as abundant peroxidative targets may both be deleterious to sperm function. Mol. Reprod. Dev. 66: 422,430, 2003. © 2003 Wiley-Liss, Inc. [source] Free IAA in stigmas and styles during pollen germination and pollen tube growth of Nicotiana tabacumPHYSIOLOGIA PLANTARUM, Issue 1 2008Dan Chen Although many studies have emphasized the importance of auxin in plant growth and development, the thorough understanding of its effect on pollen,pistil interactions is largely unknown. In this study, we investigated the role of free IAA in pollen,pistil interactions during pollen germination and tube growth in Nicotiana tabacum L. through using histo and subcellular immunolocalization with auxin monoclonal antibodies, quantification by HPLC and ELISA together with GUS staining in DR5::GUS -transformed plants. The results showed that free IAA in unpollinated styles was higher in the apical part and basal part than in the middle part, and it was more abundant in the transmitting tissue (TT). At the stage of pollen germination, IAA reached its highest content in the stigma and was mainly distributed in TT. After the pollen tubes entered the styles, the signal increased in the part where pollen tubes would enter and then rapidly declined in the part where pollen tubes had penetrated. Subcellular localization confirmed the presence of IAA in TT cells of stigmas and styles. Accordingly, a schematic diagram summarizes the changing pattern of free IAA level during flowering, pollination and pollen tube growth. Furthermore, we presented evidence that low concentration of exogenous IAA could, to a certain extent, facilitate in vitro pollen tube growth. These results suggest that IAA may be directly or indirectly involved in the pollen,pistil interactions. Additionally, some improvements of the IAA immunolocalization technique were made. [source] Simultaneous determination of main taxoids in Taxus needles extracts by solid-phase extraction-high-performance liquid chromatography with pentafluorophenyl columnBIOMEDICAL CHROMATOGRAPHY, Issue 1 2009Yu-Jie Fu Abstract A simple and accurate RP-HPLC method with pentafluorophenyl (PFP) column was developed for the simultaneous determination of six taxoids, i.e. paclitaxel, 10-deacetylbaccatin III (10-DAB III), 7-xylosyl-10-deacetyltaxol (7-xyl-10-DAT), 10-deacetyltaxol (10-DAT), cephalomannine and 7-epi-10-deacetyltaxol (7-epi-10-DAT), in the extracts from the needles of three Taxus species. The mobile phase consisted of acetonitrile (A) and water (B), and the extracts were separated using gradient elution program: 30% A at the first 7 min, and then ramped to 42% A at 8 min, held until 38 min. The developed method was validated with satisfactory precision (RSD < 2.61%), repeatability (RSD < 2.92%) and recovery (95.19,104.47%). The above taxoids in the extracts of Taxus cuspidata, T. chinensis and T. media were analyzed with the developed RP-HPLC method, and the results showed that the contents of different taxoids in three mentioned species were distinct. Maximal amounts of 10-DAB III, 7-xyl-10-DAT and 7-epi-10-DAT appeared in T. chinensis, while T. media possessed the highest content of 10-DAT, cephalomannine and paclitaxel. The developed method is accurate and efficient. It can be reliably used in the improved determination of taxoids for the quality control of Taxus species. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effect of packaging conditions on the growth of micro-organisms and the quality characteristics of fresh mushrooms (Agaricus bisporus) stored at inadequate temperaturesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2000E. González-Fandos Mushrooms were packed in two polymeric films (perforated and non-perforated PVC) and stored at 17 °C and 25 °C. The carbon dioxide and oxygen content inside the packages, aerobic mesophiles, Pseudomonas spp., faecal coliforms, Escherichia coli, anaerobic spores and major sensory factors (colour, texture, development stage and presence of moulds) were determined. The non-perforated packages had the highest contents of CO2 (6,7%), the lowest contents of O2 (0·013,0·17%) and the most desirable quality parameters (texture, development stage and absence of moulds). Pseudomonas spp. counts were around 1 logarithmic unit lower in mushrooms packaged in non-perforated film as the O2 concentrations were lower than in perforated film. The mushrooms themselves were inoculated with an enterotoxin A-producing strain of Staphylococcus aureus, packaged in overwrapped trays and stored at 17 and 25 °C. Staphylococcus aureus did not grow in the samples stored at 17 °C. Only slight growth was observed in mushrooms packaged with non-perforated film after 1 day at 25 °C. No enterotoxin was detected in any package. Faecal coliform counts were <2 log cfu g,1. Escherichia coli was not isolated in any of the samples. At 25 °C, counts of anaerobic spores of around 2 log cfu g,1 were detected in those mushrooms packaged in non-perforated film. [source] Distribution and metabolism of D/L -, L - and D -glufosinate in transgenic, glufosinate-tolerant crops of maize (Zea mays L ssp mays) and oilseed rape (Brassica napus L var napus),PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2004Monika Ruhland Abstract The aim of the present study was to determine whether post-emergence application of glufosinate to transgenic crops could lead to an increase in residues or to the formation of new, hitherto unknown metabolites. Transgenic oilseed rape and maize plants were treated separately with L -glufosinate, D -glufosinate or the racemic mixture. Whereas about 90% of the applied D -glufosinate was washed off by rain and only 5,6% was metabolised, 13,35% of the applied L -glufosinate remained in the form of metabolites and unchanged herbicide in both transgenic maize and oilseed rape. The main metabolite was N -acetyl- L -glufosinate with total residues of 91% in oilseed rape and 67% in maize, together with small amounts, of 5% in oilseed rape and 28% in maize, of different methylphosphinyl fatty acids. These metabolites were probably formed from L -glufosinate by deamination and subsequent decarboxylation. The residues were distributed in all fractions of the plants, with the highest contents in treated leaves and the lowest in the grains (0.07,0.3% in maize and 0.4,0.6% in oilseed rape). There was no indication of an accumulation of total residues or of residue levels above the official tolerances for glufosinate. Copyright © 2004 Society of Chemical Industry [source] Effects of varying dietary fatty acid profile on growth performance, fatty acid, body and tissue composition of juvenile pike perch (Sander lucioperca)AQUACULTURE NUTRITION, Issue 6 2005C. SCHULZ Abstract Pike perch (Sander lucioperca) has been identified as specie destined to diverse European inland aquaculture, but knowledge on the nutritional requirements is weak. Therefore, we investigated the effect of varying dietary fatty acid (FA) profile by partial replacement of fish oil (FO) with vegetable oils on growth, FA and body composition of juvenile pike perch. An extruded basal diet containing 59 g kg,1 crude lipids (FO) was added with 60 g kg,1 FO, 60 g kg,1 linseed oil (LO) or 60 g kg,1 soybean oil (SO). The resulting dietary FA composition differed mainly in the triglyceride fraction and was characterized by highest amounts of linolenic acid (18:3 n-3) in the LO diet and linoleic acid in the SO diet. Diet enriched with FO contained highest contents of highly unsaturated FA 20:5 n-3 (eicosapentaenic acid) and 22:6 n-3 (docosahexaenic acid). Pike perch were held in a recirculation system and each feeding group (in triplicate) was fed with experimental diets at a daily rate of 35 g kg,1 of biomass for 57 days by automatic feeders. Weight gain and specific growth rate of experimental feeding groups ranged between 18.47 and 19.58 g and 1.37,1.45% day,1 and was not affected by the dietary composition indicating that FO can be replaced by vegetable oils without negative impact on growth performance. In contrast to the whole body and muscle composition, liver tissue was affected by the varying diets. Liver tissues of fish fed diets enriched with vegetable oils showed significantly increased lipid contents of 162 (LO) and 147 (SO) g kg,1 and indicate decreased lipid utilization compared with fish fed FO diet (liver lipid content 112 g kg,1). Nevertheless, hepatosomatic index of pike perch was not influenced by dietary lipid composition. The FA profile of pike perch was generally determined by the dietary FAs. [source] | ||||||||||||||||