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971.
972.
Nutrient content of tropical edible seaweeds, Eucheuma cottonii, Caulerpa lentillifera and Sargassum polycystum 总被引:2,自引:0,他引:2
Patricia Matanjun Suhaila Mohamed Noordin M. Mustapha Kharidah Muhammad 《Journal of applied phycology》2009,21(1):75-80
The proximate composition, vitamin C, α-tocopherol, dietary fibers, minerals, fatty acid and amino acid profiles of three
tropical edible seaweeds, Eucheuma cottonii (Rhodophyta), Caulerpa lentillifera (Chlorophyta) and Sargassum polycystum (Phaeophyta) were studied. The seaweeds were high in ash (37.15–46.19%) and dietary fibers (25.05–39.67%) and low in lipid
content (0.29–1.11%) on dry weight (DW) basis. These seaweeds contained 12.01–15.53% macro-minerals (Na, K, Ca and Mg) and
7.53–71.53 mg.100 g−1 trace minerals (Fe, Zn, Cu, Se and I). The crude protein content of E. cottonii (9.76% DW) and C. lentillifera (10.41% DW) were higher than that of S. polycystum (5.4% DW), and protein chemical scores are between 20 and 67%. The PUFA content of E. cottonii was 51.55%, C. lentillifera 16.76% and S. polycystum 20.34%. Eicosapentaenoic acid (EPA), accounted for 24.98% of all fatty acids in E. cottonii. These seaweeds have significant vitamin C (∼35 mg.100 g−1) and α-tocopherol (5.85–11.29 mg.100 g−1) contents. 相似文献
973.
Khaliq S Akhtar K Afzal Ghauri M Iqbal R Mukhtar Khalid A Muddassar M 《Microbiological research》2009,164(4):469-477
Tylosin is a macrolide antibiotic used as veterinary drug and growth promoter. Attempts were made for hyper production of tylosin by a strain of Streptomyces fradiae NRRL-2702 through irradiation mutagenesis. Ultraviolet (UV) irradiation of wild-type strain caused development of six morphologically altered colony types on agar plates. After screening using Bacillus subtilis bioassay only morphological mutants indicated the production of tylosin. An increase of 2.7±0.22-fold in tylosin production (1500 mg/l) in case of mutant UV-2 in complex medium was achieved as compared to wild-type strain (550 mg/l). Gamma irradiation of mutant UV-2 using 60Co gave one morphologically altered colony type γ-1, which gave 2500 mg/l tylosin yield in complex medium. Chemically defined media promoted tylosin production upto 3800 mg/l. Maximum value of qp (3.34 mg/gh) was observed by mutant γ-1 as compared to wild strain (0.81 mg/gh). Moreover, UV irradiation associated changes were unstable with loss of tylosin activity whereas mutant γ-1 displayed high stability on subsequent culturing. 相似文献
974.
Ammar Saleem Brendan Walshe‐Roussel Cory Harris Muhammad Asim Carmen Tamayo Summer Sit John Thor Arnason 《Phytochemical analysis : PCA》2009,20(5):395-401
Introduction – Commercially available herbal mixture FE, a proprietary natural health product manufactured by Flora Manufacturing and Distributing Ltd (Flora), is a unique North American traditional herbal product. FE is a chemically complex mixture of eight herbs and has not been subjected to phytochemical analysis. Objective – To develop analytical methods to undertake detailed phytochemical analyses of FE, and its eight contributing herbs, including burdock (Arctium lappa L.), sheep sorrel (Rumex acetosella L.), Turkish rhubarb (Rheum palmatum L.), slippery elm Muhl. (Ulmus rubra), watercress (Nasturtium officinale R. Br.), red clover (Trifolium pratense L.), blessed thistle (Cnicus benedictus L.) and kelp (Laminaria digitata Lmx.). Methodology – The identification was undertaken by a combination of reversed phase high performance liquid chromatography–diode array detection–atmospheric pressure chemical ionisation–mass selective detection (RP‐HPLC‐DAD‐APCI‐MSD) analysis and phenolics metabolomic library matching. Results – New separation methods facilitated the identification of 43 markers in the individual herbs which constitute FE. Sixteen markers could be identified in FE originating from four contributing herbs including four caffeoyl quinic acids, three dicaffeoyl quinic acids and two caffeic acid derivatives from A. lappa, luteolin‐7‐O‐glucoside, luteolin, five apigenin glycosides and apigenin from R. acetocella and N. officinale and sissostrin from T. pretense. A validated method for quantitative determination of three markers is reported with good intraday, interday and interoperator repeatability using a reliable alcohol based extraction technique. Conclusion – FE and its contributing herbs predominantly contain phenolics. This methodology can be applied to further develop full‐scale validation of this product. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
975.
Extracellular Matrix Stiffness and Architecture Govern Intracellular Rheology in Cancer 总被引:2,自引:0,他引:2
Little is known about the complex interplay between the extracellular mechanical environment and the mechanical properties that characterize the dynamic intracellular environment. To elucidate this relationship in cancer, we probe the intracellular environment using particle-tracking microrheology. In three-dimensional (3D) matrices, intracellular effective creep compliance of prostate cancer cells is shown to increase with increasing extracellular matrix (ECM) stiffness, whereas modulating ECM stiffness does not significantly affect the intracellular mechanical state when cells are attached to two-dimensional (2D) matrices. Switching from 2D to 3D matrices induces an order-of-magnitude shift in intracellular effective creep compliance and apparent elastic modulus. However, for a given matrix stiffness, partial blocking of β1 integrins mitigates the shift in intracellular mechanical state that is invoked by switching from a 2D to 3D matrix architecture. This finding suggests that the increased cell-matrix engagement inherent to a 3D matrix architecture may contribute to differences observed in viscoelastic properties between cells attached to 2D matrices and cells embedded within 3D matrices. In total, our observations show that ECM stiffness and architecture can strongly influence the intracellular mechanical state of cancer cells. 相似文献
976.
A rapid, simple in vitro test system for high-throughput screening of peroxisome proliferator-activated receptor (PPAR) γ agonists would be of interest for testing new antidiabetic drugs, alternative medicine, or environmental samples. A yeast two-hybrid assay based on the ligand-dependent recruitment of the coactivator CBP (CREB-binding protein) was constructed. In this system PPARγ was constitutively activated and the signal was not further increased significantly by adding agonists. In yeast we identified oleic acid as a putative endogenous ligand. Furthermore yeasts seem to lack regulatory mechanisms present in mammalian cells. Mammalian systems are an alternative for screening PPARγ agonists. 相似文献
977.
An amperometric lactate biosensor was developed based on a conducting polymer, poly-5,2′-5′,2′′-terthiophene-3′-carboxylic acid (pTTCA), and multiwall carbon nanotube (MWNT) composite on a gold electrode. Lactate dehydrogenase (LDH) and the oxidized form of nicotinamide adenine dinucleotide (NAD+) were subsequently immobilized onto the pTTCA/MWNT composite film. The modified electrode was characterized by quartz crystal microbalance (QCM), scanning electron microscopy (SEM), and electrochemical experiments. The detection signal was amplified by the pTTCA/MWNT assembly onto which a sufficient amount of enzyme was immobilized and stabilized by the covalent bond formation between the amine groups of enzyme and the carboxylic acid groups of the pTTCA/MWNT film. Experimental parameters affecting the sensor responses, such as applied potential, pH, and temperature, were assessed and optimized. Analytical performances and dynamic ranges of the sensor were determined, and the results showed that the sensitivity, stability, and reproducibility of the sensor improved significantly using pTTCA/MWNT composite film. The calibration plot was linear (r2 = 0.9995) over the range of 5 to 90 μM. The sensitivity was approximately 0.0106 μA/μM, with a detection limit of 1 μM, based on a signal/noise ratio of 3. The applicability of the sensor for the analysis of l-lactate concentration in commercial milk and human serum samples was demonstrated successfully. 相似文献
978.
Evolution of geminiviruses and their satellites 总被引:1,自引:0,他引:1
Muhammad Shah Nawaz-ul-Rehman 《FEBS letters》2009,583(12):1825-113
Geminiviruses and their satellites have circular single stranded DNA genomes, infecting many crops and weeds across the globe. To successfully invade new hosts, break host resistance, move virus particles within and between plants, geminiviruses and their satellites have evolved a coordinated network of protein interactions, showing a possible evolutionary path. Humans have played an important role in the last century to promote the emergence of many geminivirus diseases, thereby impacting their evolution. The greatest molecular diversity of geminiviruses and their satellites resides in Southeast Asia revealing a possible center of origin. This minireview leads us to a possible general grand scheme of their evolution. 相似文献
979.
Kang SM Joo GJ Hamayun M Na CI Shin DH Kim HY Hong JK Lee IJ 《Biotechnology letters》2009,31(2):277-281
Plant growth-promoting rhizobacteria with gibberellins (GA)-producing potential were isolated from soil and screened for plant
growth promotion. A new strain, Acinetobacter calcoaceticus SE370, produced extracellular GA and also had phosphate solubilising potential. It produced 10 different gibberellins, including
the bioactive GA1, GA3 and GA4 which were at, respectively, 0.45, 6.2 and 2.8 ng/100 ml. The isolate solubilised tricalcium phosphate and lowered pH of
the medium during the process. Culture filtrates of the organism after growth on broth promoted growth of cucumber, Chinese
cabbage and crown daisy.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
980.
Khan SA Hamayun M Kim HY Yoon HJ Seo JC Choo YS Lee IJ Kim SD Rhee IK Kim JG 《Biotechnology letters》2009,31(2):283-287
Plant growth-promoting endophytic fungi with gibberellin-producing ability were isolated from the roots of Carex kobomugi Ohwi, a common sand-dune plant, and bioassayed for plant growth-promotion. A new strain, Arthrinium phaeospermum KACC43901, promoted growth of waito-c rice and Atriplex gemelinii. Analysis of its culture filtrate showed the presence of bioactive GA1 (0.5 ng/ml), GA3 (8.8 ng/ml), GA4 (4.7 ng/ml) and GA7 (2.2 ng/ml) along with physiologically inactive GA5 (0.4 ng/ml), GA9 (0.6 ng/ml), GA12 (0.4 ng/ml), GA15 (0.4 ng/ml), GA19 (0.9 ng/ml) and GA24 (1.8 ng/ml). The fungal isolate was identified through sequence homology and phylogenetic analysis of 18S rDNA (internal
transcribed region).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献