Four samples of Brazilian propolis were investigated by GC/MS of different fractions. 32 volatile compounds, (10 of them new for propolis), as well as 12 more polar compounds (one of them new for propolis) were identified. Antibacterial activity was found in some propolis fractions.

There is no other naturally occurring defense agent against cancer that has a stronger effectthan paclitaxel, commonly known under the brand name of Taxol®. The major drawback for themore widespread use of paclitaxel and its precious precursor, 10-deacetylbaccatin III (10-DABIII), is that they require large-scale extraction from different parts of yew trees (Taxus species),cell cultures, taxane...

The methods used to facilitate the supercritical fluid extraction (SFE) of polar and ionic compounds are based on two general principles, either increasing the polarity of the supercritical fluid (SF) (usually CO,) used as extractant or reducing the polarity of the analytes to be leached from the solid matrices. Changes in the pressure and temperature of the SF, the use of SFs more polar than C...

Crystalline KTiOPO4 (KTP), an inorganic nonlinear optical material with a waveguide figure-of-merit that is twice that of other mixed-metal oxides, contains helical chains of TiO(4/2)O(2/2) octahedra in which a long, short Ti-O bond motif results in a net c-directed polarization. The alternating long and short Ti-O bonds that occur along these chains are the major contributors to the large nonl...

Chlorinated biphenyl compounds have become ubiquitous components of the global environment. They were first detected in species of Swedish wildlife (1, 2, 3) and were subsequently found in seals from the North Atlantic (4), in a bird of prey in Great Britain (5), in fish and birds from the Netherlands (6), and in both terrestrial and marine species of wildlife in western North America (7). In t...

Granular activated carbons (GACS) were developed from hard and soft lignocellulosic byproducts. Three activation strategies were evaluated which employed phosphoric acid, carbon dioxide or steam. A portion of these carbons were also subjected to air oxidation after activation. Uptake of both non-polar and polar, small organic compounds were followed as was the adsorption of copper. Our results ...

Aqueous infusions of the leaves of the shrub Albertisia delagoensis (Menispermaceae) are used in South Africa in traditional Zulu medicine to alleviate a variety of symptoms, including fever, and intestinal problems. We report the analysis of such an aqueous extract using the HPLC-NMR technique. A number of polar compounds were identified, including proto-quercitol, nicotinic acid, allantoic ac...