Article

Antibacterial polyketides from the jellyfish-derived fungus Paecilomyces variotii.

College of Pharmacy, Pusan National University, Busan 609-735, Korea.
Journal of Natural Products (Impact Factor: 3.29). 07/2011; 74(8):1826-9. DOI:10.1021/np200350b
Source: PubMed

ABSTRACT Four new polyketides (1-4) were isolated from the fungus Paecilomyces variotii, which was derived from the jellyfish Nemopilema nomurai. The planar structures and relative configurations of these polyketides were elucidated on the basis of spectroscopic analyses, including 2D NMR experiments. The compounds showed inhibitory activity against pathogenic bacteria including methicillin-resistant Staphylococcus aureus 3089 and multi-drug-resistant Vibrio parahemolyticus 7001 with MIC values in the range 5-40 μg/mL.

0 0
 · 
0 Bookmarks
 · 
81 Views
  • [show abstract] [hide abstract]
    ABSTRACT: The asymmetric dihydroxylation (AD) of o-cyano cinnamates and styrene derivatives leads to efficient construction of chiral phthalide frameworks in high optical purities. This unique reaction is characterized by unusual synergism between CN and osmate groups resulting in rate enhancement of the AD process. The method is amply demonstrated by the synthesis and the structural/stereochemical assignment of the natural products.
    Organic & Biomolecular Chemistry 05/2012; 10(18):3655-61. · 3.57 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Fungi are some of the most important organisms in the production of bioactive secondary metabolites. This success is related to the advances in biotechnology and also to the possibility of working with techniques such as the "OSMAC" (one strain-many compounds) to achieve different fungal secondary metabolites profiles upon modifying the culturing conditions. Using this approach, the fungal species Paecilomyces lilacinus was cultivated in potato dextrose broth under 14 different fermentative conditions by adding the bacterium Salmonella typhimurium to the growing medium in order to provide biotic stress. S. typhimurium was added alive or after inactivation by autoclave or microwave irradiation in different stages of fungal growth. Extracts were prepared by liquid-liquid extraction using ethyl acetate, a medium polarity solvent in order to avoid extracting culturing media components. Production of fatty acids of relevance for the pharmaceutical and food industries was enhanced by the modified fermentative conditions and they were identified and quantified. The extracts were evaluated for acetylcholinesterase inhibition and the more active extract (91±2.91% inhibition) was prepared in large scale. From this active P. lilacinus extract, a novel pyridone alkaloid, named Paecilomide, was isolated and its structure was elucidated by modern nuclear magnetic resonance techniques and mass spectrometric analyses. Paecilomide (1) was also evaluated for acetylcholinesterase inhibition, presenting 57.5±5.50% of acetylcholinesterase inhibition.
    Microbiological Research 12/2012; · 1.99 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: In a palladium-catalyzed oxidative esterification, hydrosilane can serve as an activator of palladium catalyst with bismuth, thus leading to a novel ligand- and silver-free palladium catalyst system for facile oxidative esterification of a variety of benzylic alcohols in good yields.
    Chemical Communications 07/2012; 48(68):8592-4. · 6.38 Impact Factor

Full-text

View
0 Downloads
Available from