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Bioactive Metabolites (bioactive + metabolite)
Selected AbstractsThe First Total Synthesis of a Bioactive Metabolite, a Spirobenzofuran Isolated from the Fungi Acremonium sp.CHEMINFORM, Issue 4 2006HKI 0230. No abstract is available for this article. [source] Enhancement of antibiotic and secondary metabolite detection from filamentous fungi by growth on nutritional arraysJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008G.F. Bills Abstract Aims:, We asked to what extent does the application of the OSMAC (one strain, many compounds) approach lead to enhanced detection of antibiotics and secondary metabolites in fungi? Protocols for bacterial microfermentations were adapted to grow fungi in nutritional arrays. Methods and Results:, Protocols for microfermentations of non-sporulating fungi were validated using known antifungal-producing fungi. Detection of antifungal activity was often medium dependent. The effects of medium arrays and numbers of strains on detection of antifungal signals were modelled by interpolation of rarefaction curves derived from matrices of positive and negative extracts. Increasing the number of fermentation media for any given strain increased the probability of detection of growth inhibition of Candida albicans. Increasing biodiversity increased detection of antifungal phenotypes, however, nutritional arrays could partly compensate for lost antibiotic phenotypes when biodiversity was limiting. Conclusions:, Growth and extraction in microtiter plates can enable a discovery strategy emphasizing low-cost medium arrays that can better exploit the metabolic potential of strains. Significance and Impact of the Study:, Increasing fermentation parameters raise the probability of detecting bioactive metabolites from strains. The protocols can be used to pre-select strains and their growth conditions for scale up that will most likely yield antibiotics and secondary metabolites. [source] Determination of the main bioactive metabolites of Radix Salvia miltiorrhizae in Compound Danshen Dripping Pills and the tissue distribution of Danshensu in rabbit by SPE-HPLC-MSnJOURNAL OF SEPARATION SCIENCE, JSS, Issue 6 2007Zheng Xiaohui Abstract A fast solid phase extraction-high performance liquid chromatography-ion trap mass spectrometry (SPE-HPLC-MSn) method is presented for quantitative determination of 3-(3,4-dihydroxyphenyl)-2-hydroxylpropionic acid (Danshensu, DSS) from Compound Danshen Dripping Pills (CDDP) in rabbits' heart, liver, kidney, and lung and for qualitative analysis of the bioactive metabolites of Radix Salvia miltiorrhizae (DS) from CDDP in these tissues. The proposed method was validated with a detection limit of 0.06 ng/mL and a linear range of 5.0,200 ng/mL for DSS. The main metabolites of DS were pyrocatechol, vanillic acid, isopropyl 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate, and 2-hydroxyl-3-(3,4-dihydroxyphenyl)propinonic sulfuric anhydride. In vitro pharmacological experiments demonstrated that isopropyl 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate had a distinct vasodilatating action. [source] Production of bioactive metabolites by Nocardia levis MK-VL_113LETTERS IN APPLIED MICROBIOLOGY, Issue 4 2009A. Kavitha Abstract Aims:, To isolate and identify the bioactive compounds produced by Nocardia levis MK-VL_113. Methods and Results:, Cultural characteristics of Noc. levis isolated from laterite soils of Guntur region were recorded on International Streptomyces Project media. Morphological studies of the strain through scanning electron microscopy revealed the clear pattern of its hyphal fragmentation into rod-shaped bacilli. Chemical examination of the secondary metabolites of the strain grown on sucrose,tryptone broth led to the isolation of three fractions active against Bacillus cereus. Further analysis of second fraction resulted in the isolation of two active subfractions. Two different phthalate esters, namely, bis-(2-ethylhexyl) phthalate and bis-(5-ethylheptyl) phthalate, were purified from the first active subfraction, and the structural elucidation of these compounds was confirmed on the basis of FT-IR, mass and NMR spectroscopy. The partially purified second subfraction subjected to Gas Chromatography,Mass spectroscopy contained nine components: decanedioic acid; 2,6-piperdione monooxime; 1-eicosanol; beta-1-arabinopyranoside, methyl; cyclopentaneundecanoic acid; hexadecanoic acid; silane, trichloro eicosyl; 1-hexacosanol; and 1,2-dodecanediol. The antimicrobial activity of the bioactive compounds produced by Noc. levis was expressed in terms of minimum inhibitory concentration. Conclusions:, The present study clearly revealed that the metabolites of Noc. levis act as bioactive compounds against Gram-positive and Gram-negative bacteria, yeast and filamentous fungi. It also supports the idea that there are a number of rare actinomycetes remained to be explored for new bioactive compounds. Significance and Impact of the Study:, Metabolites of Noc. levis exhibited antibacterial and antifungal activities. This is the first report of bis-(5-ethylheptyl) phthalate as well as the nine partially purified compounds from actinomycetes. In addition, this is also the first report of bis-(2-ethylhexyl) phthalate from the genus Nocardia. [source] Ex situ cultivation of Aplysinaaerophoba close to in situ conditions: ecological, biochemical and histological aspectsMARINE ECOLOGY, Issue 2 2008Anne Klöppel Abstract Sponges provide the largest number of biologically active natural products known from the marine environment and continue to be a very well studied phylum of marine fauna. The Mediterranean sponge Aplysina aerophoba accumulates brominated isoxazoline alkaloids such as Aplysinamisin-1, Aerophobin-2, Isofistularin-3 and the biotransformation product Aeroplysinin-1, which possesses, for example, antibiotic and cytotoxic properties. Until now, it is still being discussed which organisms , the sponge itself or associated microorganisms , are responsible for metabolite production. For cultivating Aplysina individuals under ex situ conditions, we surveyed relevant ecological factors in situ and controlled them in our aquarium system. We maintained A. aerophoba for more than 9 months and analysed changes of metabolite content and composition, microbial association as well as morphology in situ and ex situ under different light exposure. Although sponges showed slight reduction during maintenance, ex situ cultivation similar to in situ conditions provides a promising method to keep sponges and obtain their bioactive metabolites. [source] Antimicrobial and cytotoxic activities of Malaysian endophytesPHYTOTHERAPY RESEARCH, Issue 5 2010Kalavathy Ramasamy Abstract Endophytes, which are receiving increasing attention, have been found to be potential sources of bioactive metabolites following the discovery of paclitaxel producing endophytic fungi. In the present study, a total of 348 endophytes were isolated from different parts of 24 Malaysian medicinal plants. Three selected endophytes (HAB10R12, HAB11R3 and HAB21F25) were investigated for their antimicrobial and cytotoxic activities. For antimicrobial activity, HAB10R12 and HAB11R3 were found to be most active against bacteria and fungi, respectively. Their antimicrobial effects were comparable to, if not better than, a number of current commercial antibacterial and antifungal agents. Both HAB10R12 and HAB21F25 were found to be potential anticancer drug candidates, having potent activity against MCF-7 and HCT116 cell lines and warrant further investigation. Copyright © 2009 John Wiley & Sons, Ltd. [source] Improvement of ganoderic acid and Ganoderma polysaccharide biosynthesis by Ganoderma lucidum fermentation under the inducement of Cu2+BIOTECHNOLOGY PROGRESS, Issue 2 2010Ya-Jie Tang Abstract The cell growth and total accumulation of bioactive metabolites were significantly improved by Cu2+ addition during the submerged fermentation of medicinal mushroom Ganoderma lucidum. A mathematical model, constructed by response surface methodology combination with full factorial design, was applied to study the synergic effect of Cu2+ addition concentration and addition time. The optimal Cu2+ inducement strategy for the cell growth were different from those for the biosynthesis of ganoderic acid (GA) and Ganoderma polysaccharide. A multiple additions strategy of Cu2+ by adding each 1 mM Cu2+ on day 2, 6, 8 and 2 mM Cu2+ on day 4 was developed to enhance total accumulation of GA and extracellular polysaccharides. The highest GA content reached 3.0 ± 0.1 mg per 100 mg DW, which was increased by 76.5% and 33.9% compared with the control without Cu2+ addition and the peak value predicted by the constructed mathematical model, respectively. While, relatively higher addition concentration of Cu2+ (i.e., 5 mM) on the culture of day 4 led to higher content and total production of intracellular polysaccharides. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Biochemische Interaktionen in Marinen Biofilmen.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 3 2009Kampf, Kommunikation, Kooperation Abstract Marine Mikroorganismen sind als vielseitige Produzenten von Sekundärmetaboliten bekannt. Auch wenn das Meer tausende von bioaktiven Metaboliten in den letzten zwei Jahrzehnten hervorgebracht hat, so stehen wir erst am Anfang, die natürlichen Funktionen dieser Moleküle zu erforschen. Viele Mikroorganismen kommen in der Umwelt als mehrzellige Lebensgemeinschaften, so genannten Biofilmen, vor. Dabei stellt die chemische Kommunikation einen wichtigen Mechanismus dar, wie Biofilmpopulationen ihre Verhaltensweisen koordinieren und auf Umweltveränderungen reagieren. Aktuelle Untersuchungen bringen ein komplexes Netz biochemischer Wechselbeziehungen ans Licht, über das mikrobielle Symbiosen, Konkurrenz und Verteidigung gegenüber Fraßfeinden und Parasiten vermittelt wird. Das Verstehen der molekularen Grundlagen von Biofilminteraktionen in ihrem ökologischen Kontext birgt das Potential, die Suche nach wirkspezifischen Naturstoffen und die Entwicklung von Biofilm-basierter Biotechnologien zu verfeinern. Marine microorganisms are versatile producers of secondary metabolites. Although the sea has yielded thousands of bioactive metabolites over the past two decades, we are only beginning to explore the natural functions of these molecules. Many microorganisms exist in the environment as multicellular communities, so-called biofilms. Chemical communication is an essential part of the way in which biofilm populations coordinate their behavior and respond to environmental challenges. Recent research has been unravelling a complex web of chemical crosstalk mediating microbial symbiosis, competition and defense against predators and pathogens. Understanding the molecular basis of biofilm interactions in their ecological context bears the potential of refining natural product discovery and the development of biofilm-derived biotechnologies. [source] | |||||||||||||