Seasonal variations in trans-2-hexenal and linolenic acid in homogenates of Thea sinensis leaves

The seasonal variations in the amounts of C₆-volatile components cis-3-hexenal trans-2-hexenal n-hexanal) and their precursors (linoleic and linolenic acid) in homogenates of Thea sinensis leaves were quantitatively analyzed throughout the year. Formation of trans-2-hexenal began in the middle of April and reached a maximum during July. Towards autumn the aldehyde gradually decreased and, in winter (December to March), was virtually absent. The levels of cis-3-hexenol remained constant during May–December. cis-3-Hexenal showed a similar variation pattern to that of trans-2-hexenal. The major fatty acids in the leaves were palmitic, palmitoleic, oleic, linoleic and linolenic acid, and occurred in non-ionic lipids and phospholipid fractions. The amounts of linoleic and linolenic acid did not show any marked variation except for a big peak in October.     

Expression of an inwardly rectifying K+ channel, Kir4.1, in satellite cells of rat cochlear ganglia

Satellite cellsare glial cells wrapped around somata of sensory and autonomic ganglionneurons. Neither their functional roles nor electrical properties havebeen fully clarified so far. Using immunohistochemistry, we found thatinwardly rectifying K⁺ channelsubunit Kir4.1 (also called Kir1.2 orK_AB-2) was expressed prominently in the satellite cells of cochlear ganglia. The Kir4.1 immunoreactivity was localized specifically at the myelin sheaths ofsatellite cells wrapping the somata of the ganglion neurons. Developmental expression of Kir4.1 in satellite cells paralleled development of the action potential in the auditory nerve. These results suggest that this channel in satellite cells may be responsible for the regulation of K⁺ extrudedfrom the ganglion neurons during excitation.

     

Green odor attenuates a cold pressor test-induced cardiovascular response in healthy adults

Background  

Green odor, a mixture of equal amounts of 2E-hexenal (leaf aldehyde) and 3Z-hexenol (leaf alcohol) has been demonstrated to have an anti-stress effect in rats. This study investigated whether or not green odor also has an anti-stress effect in humans.     

Evaluation of the conformational equilibrium of reduced hen egg lysozyme by antibodies to the native form

To evaluate the conformation of reduced HEL, the monoclonal antibodies HyC1 and HyC2, which recognize different conformational epitopes on native hen egg lysozyme (HEL), were used, and the kinetics of their interactions with native HEL, S-1,2-dicarboxyethylated HEL (DCE-HEL), and carboxymethylated Cys6 and Cys127 HEL (CM^6,127-HEL) were assessed using surface plasmon resonance. Although their association rate constants differed 10⁵-fold, their dissociation rate constants were essentially the same, suggesting that DCE-HEL and CM^6,127-HEL possess conformations similar to that of native HEL when they bind antibodies. We considered that the ratio of the association rate constant of reduced HEL to native HEL represents the proportion of the native format determinant in equilibrium. Reduction of the Cys6-Cys127 disulfide bond would transform the epitope recognized by HyC1 into a non-native conformation similar to that of DCE-HEL. We show that monoclonal antibodies provide a sensitive tool for evaluation of the structural and hydrodynamic changes of proteins.     

Photochemical Isomerization of Leaf Aldehyde

Isopimpinellin, bergapten, xanthotoxin, kokusagine, evoxine and japonin were isolated and identified in the leaves of Orixa japonica (Rutaceae) as feeding inhibitors against Spodoptera litura F. (Noctuidae). Isopimpinellin exhibited the most potent activity among above substances at the feeding inhibitory test. The isolated evoxine was the optical antipode of the previously reported one.