ABSTRACT
A compound of unusual structure was isolated from red beetroot (Beta vulgaris) peel extract and identified as 5,5',6,6'-tetrahydroxy-3,3'-biindolyl based on the combination of NMR and MS studies.
Subject(s)
Beta vulgaris/chemistry , Indoles/chemistry , Plant Extracts/chemistry , Acetylation , Chromatography, High Pressure Liquid , Indoles/isolation & purification , Mass Spectrometry , Molecular Conformation , Molecular Structure , Plant Extracts/isolation & purification , Plant Stems/chemistry , Spectrometry, Mass, Electrospray IonizationABSTRACT
An antibiotic produced by the symbiotic actinomycete Frankia strain AiPs1 was isolated from culture broth using optimized thin-layer chromatography and high-performance liquid chromatography (HPLC) methods. The novel compound that was isolated, dubbed frankiamide, displayed antimicrobial activity against all 14 Gram-positive bacterial strains and six pathogenic fungal strains tested. The pathogenic actinomycete Clavibacter michiganensis and the oomycete Phytophthora were especially susceptible. In addition to displaying antimicrobial activity, frankiamide also strongly inhibited 45Ca(2+) fluxes in clonal rat pituitary GH4C1 tumor cells and was comparable to a frequently used calcium antagonist, verapamil hydrochloride. The results of HPLC analysis, supported by both nuclear magnetic resonance and mass spectroscopy studies, showed that frankiamide has a high affinity for Na(+) ions.
Subject(s)
Amides/isolation & purification , Amides/pharmacology , Calcium/antagonists & inhibitors , Fungi/drug effects , Gram-Positive Bacteria/drug effects , Heterocyclic Compounds/isolation & purification , Heterocyclic Compounds/pharmacology , Imides/isolation & purification , Imides/pharmacology , Actinomycetales/growth & development , Actinomycetales/metabolism , Amides/chemistry , Animals , Calcium/metabolism , Cells, Cultured , Heterocyclic Compounds/chemistry , Imides/chemistry , Microbial Sensitivity Tests , Pituitary Gland/cytology , RatsSubject(s)
Actinomycetales/chemistry , Amides/chemistry , Anti-Bacterial Agents/chemistry , Heterocyclic Compounds/chemistry , Imides/chemistry , Amides/isolation & purification , Anti-Bacterial Agents/isolation & purification , Heterocyclic Compounds/isolation & purification , Imides/isolation & purification , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Fast Atom BombardmentABSTRACT
The distribution of total phenolics and main betacyanins in red beetroot (Beta vulgaris) root was determined. Also, the subsequent effects of cold storage on the content of total phenolics, main betacyanins (betanin and isobetanin), and the main known ferulic acid ester (beta-D-fructofuranosyl-alpha-D-(6-O-(E)-feruloylglucopyranoside) were determined in the peel, which is the root part containing the largest amount of total phenolics. The content of total phenolics in the red beetroot water extracts was determined according to a modification of the Folin-Ciocalteu method and expressed as gallic acid equivalents (GAE). The compounds of interest were identified by HPLC-ESI-MS and NMR techniques, and the contents of compounds were determined by HLPC analyses. The total phenolic contents in various root parts were found to decrease in the order peel, crown, flesh. Significant differences in the contents of total phenolics and individual compounds were found when the effect of cold storage (5 degrees C, 0-196 days) on the constituents of the peel from intact roots was examined. In addition to the betacyanins of red beetroot peel found in our earlier study, tentative identifications of betanidin and feruloylamaranthin were made.
Subject(s)
Chenopodiaceae/chemistry , Food Preservation , Phenols/analysis , Vegetables/chemistry , Chromatography, High Pressure Liquid , Cold Temperature , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Conformation , Phenols/chemistry , Plant Roots/chemistry , Spectrometry, Mass, Electrospray IonizationABSTRACT
The genetic engineering of antibiotic-producing Streptomyces strains is an approach that is emerging and ready to become established as a successful methodology in developing analogues of the original, pharmaceutically important, natural products obtained from the organisms. The current report highlights this succes by demonstrating the high-level production of novel anthracyclines. The biosynthetic pathways of the nogalamycin-producing Streptomyces nogalater and the aclacinomycin-producing S. galilaeus were combined by transferring the genes of S. nogalater polyketide synthetase into a nonproducing S. galilaeus mutant. The resulting anthracycline antibiotics that were produced possessed structural features characteristic of compounds from both of the undoctored Streptomycesstrains.
Subject(s)
Antibiotics, Antineoplastic/biosynthesis , Streptomyces/genetics , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/isolation & purification , Carbohydrate Sequence , Fermentation , Genetic Engineering , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Mutation/genetics , Spectrophotometry, Ultraviolet , Streptomyces/chemistryABSTRACT
Compounds produced by the polyketide ketoreductase deficient Streptomyces mutants HO61 and P67 are described. The structures of the compounds indicate that ketoreductase activity is required for correct condensation of the polyketide chain in the biosynthesis of aromatic polyketides.
