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81.
Marit Espe Raja Mansingh Rathore Zhen-Yu Du Bjørn Liaset Adel El-Mowafi 《Amino acids》2010,39(2):449-460
The current experiment aimed to study whether interactions with lipid metabolism possibly might explain the relative increased
liver weight obtained in fish fed sub-optimal methionine levels. A basal diet based on a blend of plant proteins which is
low in methionine (1.6 g Met/16 g N) was compared to a methionine adequate diet (2.2 g Met/16 g N) prepared by adding dl-methionine (2.4 g/kg) to the basal diet in the expense of wheat grain. Fish oil was used as the lipid source. The diets were
balanced in all nutrients except methionine. The diets were fed to Atlantic salmon (500 g BW) for a period of 3 months. Feed
intake did not differ, rendering the intake of all nutrients except methionine equal. Fish fed the low methionine diet had
an increased liver size relative to body weight, indicating fat deposition in the liver. Fish given the sub-optimal methionine
diet showed about six times higher fatty acid synthase (FAS) activity as compared to the fish fed the adequate methionine
diet, indicating a higher de novo lipogenesis. A significant rise in the liver 18:1 to 18:0 fatty acid ratios also supported
storage of lipids over fatty acid oxidation. Indeed, methionine limitation resulted in significantly higher TAG concentrations
in the liver. Sub-optimal dietary methionine also resulted in lower hepatic taurine concentrations and the total bile acids
concentrations were reduced in faeces and tended to be reduced in plasma. Taken together, our data show that salmon fed sub-optimal
methionine levels had increased relative liver weight and developed signs commonly described in the early stage of non-alcoholic
fatty liver disease in rodent models (increased FAS activity, changed fatty acid ratios and TAG accumulation). 相似文献
82.
Amylase inhibitor producing actinobacteria were isolated and characterized from terrestrial environment and there is no much
report found from marine environment, hence in the present study, 17 strains isolated from the rhizosphere sediments of mangroves
were tested for their amylase inhibition ability. Seawater requirement test for the growth of actinobacteria found that the
strains SSR-3, SSR-12 and SSR-16 requires at least 50% and SSR-6 requires at least 25% seawater for their growth. The inhibition
activity of both prokaryotic and eukaryotic amylase was tested by using Bacillus subtilis and Aspergillus niger. The maximum amylase activity (40mm) produced by the A. niger was taken as positive control, when the test actinobacteria strains grown in the medium they inhibited amylase activity and
was evidenced by the reduction in inhibition zone (14–37 mm) similarly the amylase produced by the Bacillus subtilis was also recorded maximum (35 mm) amylase activity and was taken as positive control, and the test atinobacterial strains
reduced enzyme action(12–33 mm) it varied levals. This indicates that the actinobacteria strains were controlled amylase enzyme
activity in both the cases. The strain SSR-10 was highly effective and SSR-8 was less effective in inhibiting eukaryotic amylase
produced by A. niger. The strain SSR-2 was effective and SSR-6 showed very less effect in inhibiting the prokaryotic amylase produced by the B subtilis. 相似文献
83.
84.
Brian Sheng Xian Teo Mahiran Basri Mohd Rezuwan Shah Zakaria Abu Bakar Salleh Raja Noor Zaliha Raja Abdul Rahman Mohd Basyaruddin Abdul Rahman 《Journal of nanobiotechnology》2010,8(1):4
Background
Cosmeceuticals are cosmetic-pharmaceutical hybrids intended to enhance health and beauty of the skin. Nanocosmeceuticals use nano-sized system for the delivery of active ingredients to the targeted cells for better penetration. In this work, nanoemulsion from palm oil esters was developed as a delivery system to produce nanocosmeceuticals. The stability of the resulting formulation was tested using various methods. In addition, the effect of components i.e. Vitamin E and Pluronic F-68 on the formulation was also studied. 相似文献85.
Raja Brauner Anu Bashamboo Sébastien Rouget Marie Goulet Pascal Philibert Hélène Sarda-Thibault Christine Trivin Micheline Misrahi Charles Sultan Ken McElreavey 《PloS one》2010,5(6)
Background
The cause of isolated gonadotropin-independent precocious puberty (PP) with an ovarian cyst is unknown in the majority of cases. Here, we describe 11 new cases of peripheral PP and, based on phenotypes observed in mouse models, we tested the hypothesis that mutations in the GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX may be associated with this phenotype.Methodology/Principal Findings
11 girls with gonadotropin-independent PP were included in this study. Three girls were seen for a history of prenatal ovarian cyst, 6 girls for breast development, and 2 girls for vaginal bleeding. With one exception, all girls were seen before 8 years of age. In 8 cases, an ovarian cyst was detected, and in one case, suspected. One other case has polycystic ovaries, and the remaining case was referred for vaginal bleeding. Four patients had a familial history of ovarian anomalies and/or infertility. Mutations in the coding sequences of the candidate genes GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX were not observed.Conclusions/Significance
Ovarian PP shows markedly different clinical features from central PP. Our data suggest that mutations in the GNAS1, NR5A1, LHCGR, FSHR StAR, DMRT4 and NOBOX genes are not responsible for ovarian PP. Further research, including the identification of familial cases, is needed to understand the etiology of ovarian PP. 相似文献86.
Claude Vallet Raja Sa?&#x;d Claude Rabiller Maryvonne L. Martin 《Bioorganic chemistry》1996,24(4):319-330
Site-specific natural isotope fractionation studied by nuclear magnetic resonance (SNIF-NMR) provides isotopic criteria that characterize a biochemical transformation such as fermentation and enable isotopic ratios measured in end products to be correlated with those of their precursors. In principle, a given set of transfer coefficients applies only to bioconversions performed under strictly identical conditions, a situation that is hardly fulfilled in most usual fermentation processes. In particular, natural raw materials such as fruits frequently involve complex mixtures of various yeast strains present at different concentrations. Series of experiments performed with different yeasts, different concentrations of car- bohydrates, and different yields of the transformation have shown that, although glycolysis is associated with overall hydrogen fractionation effects that may exceed 40 ppm, the range of variation in the isotopic ratios of the fermentation products, ethanol and water, does not exceed a few parts per million. Provided that the yield in ethanol reaches values higher than 70%, the nature of the yeast strain has minimal influence on the isotopic ratio of the methyl site of ethanol (D/H)I. In contrast, the isotope ratio of the methylene site, (D/H)II, may exhibit significant enhancements, in particular when ethanol is left in contact for a long time with poorly alcohologenic yeasts. These behaviors are consistent with hydrogen transfers from the aqueous medium to the methylene site, and partly to the methyl site, occurring with relatively high kinetic isotope effects. Since water acts as an open pool of hydrogens, however, only small isotopic variations are produced in the course of the fermentation reaction. Moreover, the partial connection between hydrogens from the methyl site of ethanol and hydrogens from glucose operates with relatively small secondary isotopic effects. No significant changes in the percentages of intra- and inter-molecular transfers of hydrogen to the methyl site are observed as a function of the nature of the yeast. These results support the use of the methyl isotopic ratio of ethanol as a probe of the isotopic behavior of carbohydrate precursors, whatever the yeast strains present in natural fermentation media. 相似文献
87.
Carol A. Shearer Enrique Descals Brigitte Kohlmeyer Jan Kohlmeyer Ludmila Marvanová David Padgett David Porter Huzefa A. Raja John P. Schmit Holly A. Thorton Hermann Voglymayr 《Biodiversity and Conservation》2007,16(1):49-67
Fungal biodiversity in freshwater, brackish and marine habitats was estimated based on reports in the literature. The taxonomic
groups treated were those with species commonly found on submerged substrates in aquatic habitats: Ascomycetes (exclusive of yeasts), Basidiomycetes, Chytridiomycetes, and the non-fungal Saprolegniales in the Class Oomycetes. Based on presence/absence data for a large number and variety of aquatic habitats, about 3,000 fungal species and 138 saprolegnialean
species have been reported from aquatic habitats. The greatest number of taxa comprise the Ascomycetes, including mitosporic taxa, and Chytridiomycetes. Taxa of Basidiomycetes are, for the most part, excluded from aquatic habitats. The greatest biodiversity for all groups occurs in temperate areas,
followed by Asian tropical areas. This pattern may be an artifact of the location of most of the sampling effort. The least
sampled geographic areas include Africa, Australia, China, South America and boreal and tropical regions worldwide. Some species
overlap occurs among terrestrial and freshwater taxa but little species overlap occurs among freshwater and marine taxa. We
predict that many species remain to be discovered in aquatic habitats given the few taxonomic specialists studying these fungi,
the few substrate types studied intensively, and the vast geographical area not yet sampled. 相似文献
88.
A new organic solvent tolerant protease from <Emphasis Type="Italic">Bacillus pumilus</Emphasis> 115b 总被引:3,自引:0,他引:3
Rahman RN Mahamad S Salleh AB Basri M 《Journal of industrial microbiology & biotechnology》2007,34(7):509-517
Five out of the nine benzene–toulene–ethylbenzene-xylene (BTEX) tolerant bacteria that demonstrated high protease activity
on skim milk agar were isolated. Among them, isolate 115b identified as Bacillus pumilus exhibited the highest protease production. The protease produced was stable in 25% (v/v) benzene and toluene and it was activated
1.7 and 2.5- fold by n-dodecane and n-tetradecane, respectively. The gene encoding the organic solvent tolerant protease was cloned and its nucleotide sequence
determined. Sequence analysis revealed an open reading frame (ORF) of 1,149 bp that encoded a polypeptide of 383 amino acid
residues. The polypeptide composed of 29 residues of signal peptide, a propeptide of 79 residues and a mature protein of 275
amino acids with a calculated molecular mass of 27,846 Da. This is the only report available to date on organic solvent tolerant
protease from B. pumilus. 相似文献
89.
Raja Noor Zaliha Raja Abd Rahman Thean Chor Leow Abu Bakar Salleh Mahiran Basri 《BMC microbiology》2007,7(1):77
Background
Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0) as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%). Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification. 相似文献90.