A new flavonol from the kino of Eucalyptus citriodora.

A new flavonol, 6-[1-(p-hydroxyphenyl)ethyl]rhamnocitrin (3) together with two known compounds, kaempferol (4) and 7-O-methyl aromadendrin (5) were isolated from the kino of Eucalyptus citriodora and their structures were elucidated on the basis of spectroscopic methods including 2D NMR spectra. Rhamnocitrin (1), 6-[1-(p-hydroxyphenyl)ethyl]-7-O-methyl aromadendrin (2), previously isolated from this plant and compounds 3-5 were tested for inhibitory activity against 15-lipoxygenase. All compounds exhibited moderate to strong inhibitory activities, of which compounds 2, 3 and 5 showed stronger inhibitory activity (IC 19.

Antioxidant and antityrosinase activity of mulberry (Morus alba L.) twigs and root bark.

The antioxidant and antityrosinase activities of the ethanolic extract of mulberry twigs (EEMT) were investigated. The results showed that EEMT exhibited radical scavenging and reducing activity, as well as ferrous ion-chelating activity. In addition, EEMT also protected phospholipids against free radicals, indicating that EEMT could protect biomolecules from oxidative damage.

Antioxidative characteristics and inhibition of alpha-melanocyte-stimulating hormone-stimulated melanogenesis of vanillin and vanillic acid from Origanum vulgare.

The antioxidant activities of vanillin and vanillic acid isolated from Origanum vulgare are investigated. These compounds may serve as agents for antimelanogenesis. Vanillic acid is a stronger antioxidant than vanillin, in terms of free radical scavenging activity, reducing power and inhibition of lipid peroxidation.

The characteristics and transfection efficiency of cationic poly (ester-co-urethane) - short chain PEI conjugates self-assembled with DNA.

To improve the transfection efficiency of polycations with DNA, we synthesized poly(ester-co-urethane)(PEU-g-PEI800) with short chain PEI800 in the side chain, and poly(ester-co-urethane)(PEU) without short chain PEI800. Both PEU-g-PEI800 and PEU, readily self-assembled with plasmid DNA (pCMV-betagal) in a HEPES buffer, were characterized by dynamic light scattering and zeta-potential. The results reveal that PEU-g-PEI800 and PEU were able to self-assemble particles with DNA and yield nano-sized complexes (<200nm) with positive charge at N/P ratios of 20/1 and 120/1, respectively.