We have shown Xanthium strumarium exhibit two distinct leaf movement rhythms with one occurring in continuous light and presumably related to an endogenous rhythm initiated by the "light-on" signal and the other occurring in continuous dark and presumably related to an endogenous rhythm initiated by the "light-off" signal. Characteristic of the light-on rhythm is a sudden and rapid downward mov...

RXR is a nuclear receptor that plays a central role in cell signaling by pairing with a host of other receptors. Previously, 9-cis-retinoic acid (9cRA) was defined as a potent RXR activator. Here we describe a unique RXR effector identified from organic extracts of bovine serum by following RXR-dependent transcriptional activity. Structural analyses of material in active fractions pointed to th...

Investigation of the chemical composition of the essential oils from subterranean organs (S) of Nephrolepis cordifolia (NC) and Nephrolepis exaltata (NE) (F. Lomariopsidaceae) grown in Egypt was carried out. Gas Chromatography/mass Spectrometry (GC/MS) analysis of the hydro-distilled NCS and NES oils revealed that oxygenated compounds were abundant, being 55.35% and 33.85%, respectively. Ethyl ...

Liverworts belonging to the Class Hepaticae of the Division Bryophyta, are an excellent source of lower terpenoids. They possess intracellular oil bodies which are composed of lipophilic terpenoids and aromatic compounds. In this study, an attempt was made to identify the prenyllipid component that is localized to the chloroplasts of the liverwort, Heteroscyphus planus (Mitt.) Shiffner. The pre...

PURPOSE The aim of this work was to identify the chemical composition of the essential oils obtained from the flowers and leaves of Elaeagnus angostifolia (Elaeagnaceae) along with evaluate the radical scavenging and general toxicity activities. METHODS A combination of GC-MS and GC-FID were utilized for analyzing the chemical profile of the essential oils extracted by hydro-distillation from...

Chlorophyll degradation is vital during leaf senescence and fruit ripening, as it allows for recycling of nitrogen and other nutrients and for protection from buildup of phototoxic chlorophyll intermediates (Hörtensteiner, 2006). The first steps in chlorophyll breakdown are the removal of the phytol tail (dephytylation) and the central Mg atom. It has been thought that dephytylation typically o...