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The ability to be used as an alternative solvent of a cis-rich pinane (cis/trans: 7/3), which was obtained for the first time at the multigram scale through an environmentally friendly catalytic hydrogenation of α/β-pinenes or turpentine oil under neat conditions over a Pd/C catalyst, was investigated and compared to n-hexane for the extraction of several bioactive compounds. Experimental evaluation as well as a simulation of the cis-rich pinane extraction capacity have been undertaken. The predictive approach was performed using the simulation software COSMO-RS (conductor like screening model for realistic solvents), which uses a statistical thermodynamics approach based on the result of quantum chemical calculation, for the understanding of dissolving mechanism. COSMO-RS simulation showed that the bio-based solvent is a good solvent to solubilize carotenoids, oil from rapeseed and aromas from caraway seeds. The experimental results indicated that the highest carotenoid yield was obtained with the cis-rich pinane with 95.4% of the maximum carotenoid content in carrots while n-hexane was only able to extract 78.1% of them. With respect to the extraction of oil from rapeseeds, both solvents showed similar extraction yields and no differences were observed in the fatty acid profiles. In relation to the aromas, the characterization of the essential oil extracted by the two solvents showed a similar composition, where carvone (64%) was the main component followed by limonene (34%). No selectivity of the solvents was observed for any of the two major compounds. The results indicate that the bio-based solvent could be a promising solvent for n-hexane substitution. [ABSTRACT FROM AUTHOR]

Astaxanthin (ASTX) is a keto carotenoid, which possesses a non-polar linear central conjugated chain and polar β-ionone rings with ketone and hydroxyl groups at the extreme ends. It is well known as a super anti-oxidant, and recent clinical studies have established its nutritional benefits. Although it occurs in several forms, including free molecule, crystalline, aggregates and various geometrical isomers, in nature it exists primarily in the form of esters. Marine animals accumulate ASTX from primary sources such as algae. Nordic shrimps (P. borealis), which are harvested widely in the Atlantic Ocean, form a major source of astaxanthin esters. “Astaxanthin-rich shrimp oil” was developed as a novel product in a shrimp processing plant in Eastern Canada. A compositional analysis of the shrimp oil was performed, with a view to possibly use it as a nutraceutical product for humans and animals. Astaxanthin-rich shrimp oil contains 50% MUFAs and 22% PUFAs, of which 20% are omega-3. In addition, the shrimp oil contains interesting amounts of EPA and DHA, with 10%/w and 8%/w, respectively. Astaxanthin concentrations varied between 400 and 1000 ppm, depending on the harvesting season of the shrimp. Astaxanthin and its esters were isolated from the oil and analysed by NMR, FTIR and Micro-Raman spectroscopy. Astaxanthin mono- and diesters were synthesized and used as standards for the analysis of astaxanthin-rich shrimp oil. NMR and vibrational spectroscopy techniques were successfully used for the rapid characterization of monoesters and diesters of astaxanthin. Raman spectroscopy provided important intermolecular interactions present in the esterified forms of astaxanthin molecules. Also discussed in this paper is the use of NMR, FTIR and Micro-Raman spectroscopy for the detection of astaxanthin esters in shrimp oil. [ABSTRACT FROM AUTHOR]

Several oligomannoside clusters having a hundred-fold increase in affinities toward E. coli were synthesized by Cu(I)-catalyzed [1,3]-dipolar cycloadditions using pentaerythritol scaffolds bearing either alkyne or azide functionalities.