118 research outputs found
Chemical Composition of Corallina mediterranea Areschoug and Corallina granifera Ell. et Soland
Abstract
The composition of sterols, volatiles and some polar compounds from three Corallina samples (C. granifera and C. mediterranea from the Black Sea and C. mediterranea from the Mediterranean Sea) was established. The sterol composition of the Black Sea samples was similar but it differs from that of the Mediterranean sample. The composition of the volatiles was very complex. The main groups of constituent were hydrocarbons, alcohols, carbonyl compounds, acids and their esters, terpenes. The composition of the polar components, soluble in n-butanol, was also established. There were some differences in the chemical composition of the two Black Sea species, which may be due to the biodiversity between them, while the differences in the composition of the two C. mediterranea samples could be due to the differences in the environment (salinity, temperature, pollution, etc.)
The specific chemical profile of Mediterranean propolis from Malta
Seventeen Maltese propolis samples were studied by GC–MS after silylation. They exhibited the typical
Mediterranean chemical profile, rich in diterpene compounds (18–92% of TIC, GC–MS): 32 individual
diterpenes were identified; 22 of them were present in each specimen. The other abundant compound
group was that of sugars and sugar derivatives. In some samples, however, another compound group
was observed (0–12% of TIC, GC–MS); the corresponding mass spectra were consistent with monoand
sesquiterpenyl esters of substituted benzoic acids. Two new propolis constituents of this group, daucane
diterpene esters of hydroxybenzoic acids, were isolated. Their origin is suggested to be Ferula communis,
as they are taxonomic markers for this species. All propolis samples were active against
Staphylococcus aureus but only those with high concentrations of terpenyl esters showed antifungal activity
against Candida albicans. The present results confirm that Mediterranean propolis is a valuable natural
product with potential to improve human health.peer-reviewe
Chemical composition and biological activities of the Black Sea algae Polysiphonia denudata (Dillw.) Kutz. and Polysiphonia denudata f. fragilis (Sperk) Woronich.
Abstract
The two investigated algae had almost identical sterol composition, but there were significant differences in the com position of the polar components and especially in the composition of the volatiles. P. denudata f. fragilis extracts possessed a stronger biological activity (antibacterial, antifungal and toxicity against Artemia salina). Despite the minute morphological differences between the two algae, we recommend P. denudata f. fragilis to be regarded as P. denudata subsp. fragilis
Chemical composition of the brown alga Padina pavonia (L.) Gaill. from the adriatic sea
The chemical composition of the brown alga Padina pavonia (L.) Gaill. from the southern Adriatic Sea was investigated. Twelve sterols were identified in the sterol fraction, the main ones being cholesterol and fucosterol. The main fatty acids in the lipids were also identified.The most abundant fatty acid was palmitic acid, followed by oleic and myristic acids.The concentration of polyunsaturated fatty acids was unusually low for a marine alga. By GC/MS analysis of the volatile and polar fractions, 40 compounds were identified. Some of them probably possess defensive functions. In the volatile fraction free fatty acids, aromatic esters, benzyl alcohol and benzaldehyde predominated. Low concentrations of terpenoids, phenols and sulfur containing compounds were also identified.The nbutanol extract contained mainly fatty acids and polyols. Some of the extracts had an antibacterial activity
Antibacterial mono- and sesquiterpene esters of benzoic acids from Iranian propolis
<p>Abstract</p> <p>Background</p> <p>Propolis (bee glue) has been used as a remedy since ancient times. Propolis from unexplored regions attracts the attention of scientists in the search for new bioactive molecules.</p> <p>Results</p> <p>From Iranian propolis from the Isfahan province, five individual components were isolated: the prenylated coumarin suberosin <b>1</b>, and four terpene esters: tschimgin (bornyl <it>p</it>-hydroxybenzoate) <b>2</b>, tschimganin (bornyl vanillate) <b>3</b>, ferutinin (ferutinol <it>p</it>-hydroxybenzoate) <b>4, </b>and tefernin (ferutinol vanillate) <b>5</b>. All of them were found for the first time in propolis. Compounds <b>2 </b>- <b>5 </b>demonstrated activity against <it>Staphylococcus aureus</it>.</p> <p>Conclusions</p> <p>The results of the present study are consistent with the idea that propolis from unexplored regions is a promising source of biologically active compounds.</p
Food-borne infections caused by enteropathogenic Yersinia - incidence, surveillance, microbiological and epidemiological aspects
Yersinia enterocolitica and Y. pseudotuberculоsis are the causative agents of foodborne zoonosis called yersiniosis. In 2011 it was the forth most commonly reported zoonosis in EU, nevertheless the tendancy of decreasing five-year trend (2007-2011). Yersiniosis is reported анд десцрибед in different animal species, e.g. wild animals and birds. Both enteropathogenic bacterial agents are ubiquitous and easily adaptable to the environment, what is an important precondition for infection of a wide variety of animals and contamination of water, soil, feed, vegetables, etc. Concidering the growing public health concern for human pathogenic biotypes and serotypes of Yersinia, as well as the role of slaughter pigs as major reservoir for the foodborne transmission of Y. enterocolitica, essential microbiological experimental findings and epidemiological data are presented. Molecular approaches for detection and identification are discussed too
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