Marine macroalgae analyzed by mass spectrometry are rich sources of polyunsaturated fatty acids.

Algae from cold water (Canada) and warm water (China) were analyzed for their total lipid content, and for their fatty acid (FA) composition and content. The major findings are that FA from Canadian algae are generally richer in polyunsaturated FA (PUFA), with a higher n-3/n-6 FA ratio, and a higher degree of total unsaturation. The 18 C, 4 double bonds FA (18 : 4 stearidonic acid, morotic acid as synonym) was detected in greater amounts in cold water samples. The high levels of total PUFA, and especially of n-3 FA in Canadian algae, suggests their possible utilizations for nutritional purposes.

Rapid evaluation of phenolic component profile and analysis of oleuropein aglycon in olive oil by atmospheric pressure chemical ionization-mass spectrometry (APCI-MS).

Epidemiological studies have linked the Mediterranean diet with a low incidence of cardiovascular diseases. Olive oil, the major fat component of this diet, is characterized by antioxidant properties related to their content in catecholic components, particularly oleuropein aglycon. Therefore quantification of these components in edible oils may be important in determining the quality, and consequently its commercial value. The present method allows us to obtain the profile of the phenolic components of the oil from the methanolic extracts of the crude olive oil. In particular tyrosol, hydroxytyrosol, elenolic acid, deacetoxyligstroside and deacetoxyoleuropein aglycons, ligstroside and oleuropein aglycons, and 10-hydroxy-oleuropein are clearly identified by atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). Moreover, oleuropein and its isomers present in the oil are quantified by APCI-MS/MS analysis of the extracts without preliminary separation from other phenolic compounds.

Marine macroalgae as sources of polyunsaturated fatty acids.

Algae from cold water (Canada) and warm water (China) were analysed for the total lipid content, and for their fatty acid (FA) composition and content. The major findings are that fatty acids (FA) from Canadian algae are generally richer in polyunsaturated FA (PUFA), with a higher n-3/n-6 FA ratio, and a higher degree of total unsaturation. The C 18:4 FA (stearidonic acid, morotic acid as synonym) was detected in greater amounts in cold water samples. The high levels of total PUFA, and especially of n-3 FA in Canadian algae, suggests possible utilization for nutritional purposes.

Bovine seminal plasma contains factors that enhance lymphocyte transformation in vitro.

The important immunosuppressive properties of seminal plasma have significant functions in the processes of reproduction. They mask the presence of an immunostimulating activity. From bovine seminal plasma two active factors have been isolated and characterized with marked enhancing activity for in vitro PHA-dependent lymphocyte transformation. They have inosine and hypoxanthine structures, as confirmed by UV absorption profiles, TLC, mass spectrometry, HPLC patterns, behavior to enzymatic treatments, and breaking of purine ring after acid treatment. Nevertheless, their biological activities are about two orders of magnitude higher than those of commercially available inosine and hypoxanthine standards. Biological activities became practically identical when these were processed (HPLC) in the same way as native molecules. A study to explain such a discrepancy is in progress.

Effect of virgin olive oil phenolic compounds on in vitro oxidation of human low density lipoproteins.

BACKGROUND AND AIM: Substantial evidence suggests that oxidative modifications of low density lipoproteins (LDL) critically contribute to the pathogenesis and progression of human atherosclerosis. Oxidized LDL (oxLDL) are present in atherosclerotic plaques and contain oxysterols that exhibit a variety of adverse biological activities. Antioxidants have also been shown to prevent LDL modification. We have therefore assessed the efficacy of virgin olive oil phenolic compounds in preventing oxidative modifications of human LDL oxidized by UV light. METHODS AND RESULTS: Cholesterol oxides formed during LDL photo-oxidation were determined by UV-HPLC in the presence of different concentrations of phenolic compounds and their pure components (tyrosol and oleuropein), and probucol, a widely used synthetic antioxidant. Electrophoretic mobility was also assayed. The results demonstrate that phenolic compounds are much more potent in preventing cholesterol oxide formation and apoproteic moiety modification than their pure components and probucol. CONCLUSIONS: The beneficial effects of a Mediterranean diet may be ascribable not only to the high unsaturated/saturated fatty acid ratio characteristic of olive oil, but also to the unique antioxidant properties of its phenolic compounds.

Analysis by high-performance liquid chromatography of teucrin A in beverages flavoured with an extract of Teucrium chamaedrys L.

Due to its liver toxicity, the medicinal use of germander (Teucrium chamaedrys L.) was banned in some countries. Nevertheless, alcoholic extracts are still permitted as flavour ingredients since they are fundamental in providing a bitter aromatic taste. Teucrin A represents the substance of major concern regarding the potential toxicity of germander. Hence, teucrin A represents the best analytical and toxicological marker of alcoholic extracts of T. chamaedrys. A sensitive high-performance liquid chromatography method to detect teucrin A in beverages is reported. Teucrin A was prepared by isolation from the plant extract using column chromatography and crystallization. The identity and purity (99%) were established by melting point, nuclear magnetic resonance and liquid chromatography-mass spectrometry. The high-performance liquid chromatography procedure was validated and its intra- and interday performance was established (relative standard deviation < or = 13% and error < or = 10%). In-house validation was carried out by analysing samples of beverages not containing T. chamaedrys spiked with a range of concentrations of teucrin A. The limit of detection was 0.1 ppm and the limit of quantification was 0.3 ppm. Teucrin A accounted for about 70% of the neo-clerodane diterpenoids found in the total extract of a specimen of T. chamaedrys. The content (+/- standard deviation) in 18 batches of different geographical origin was 2338 +/- 740 ppm, per cent coefficient of variation = 32, minimum-maximum = 999 - 3445 ppm. The mean level of teucrin A in 10 bottles of the same brand was 6.1 +/- 0.8 ppm, per cent coefficient of variation = 12. In 10 different brands found on the Italian market, the content of teucrin A ranged from not detectable to 10 ppm.

Pharmacokinetics and metabolism of oral diosmin in healthy volunteers.

Pharmacokinetic studies of diosmin were performed after an oral administration to healthy volunteers. Diosmin and its aglycone, diosmetin, were determined by HPLC and LC-MS techniques. At least, at the level of sensitivity of our method, no parent compound was present in the plasma but only its aglycone, diosmetin. Analysis of the pharmacokinetic parameters showed that the drug was rapidly absorbed. Diosmetin presents a long plasma elimination half-life ranging from 26 to 43 hours. Our data show the total absence of urinary elimination for both diosmin and its aglycone diosmetin, while its minor metabolites are eliminated in the urine, mainly as glucuronic acid conjugates. The presence of degradation products such as alkyl-phenolic acids confirms a metabolic pattern similar to other flavonoids.

Molecular models of acidic peptides from pea bud chromatin and seminal plasma. Divalent cations-mediated interaction with DNA.

Small acidic peptides have been isolated from biological fluids (blood and seminal plasma) and from chromatin of several tissues. Their biological activity is related to the control of cell growth and gene expression. This work is an approach to the study of peptide structure-function relationship. Purified fractions from seminal plasma and pea bud chromatin were subjected to fast ion bombardment mass spectrometry. The results obtained were analyzed according to biochemical characteristics of the peptides studied and some possible molecular models have been designed. Two of the proposed sequences were synthesized and their biological activity assayed in cells and cell-free systems. The results demonstrate that the synthetic peptides are able to bind to DNA in the presence of divalent cations (Mg2+, Fe2+, Cu2+) with consequent inhibition of DNA transcription.