Food for thought: dietary changes in essential fatty acid ratios and the increase in autism spectrum disorders.

The last decades have shown a spectacular and partially unexplained rise in the prevalence of autism spectrum disorders (ASD). This rise in ASD seems to parallel changes in the dietary composition of fatty acids. This change is marked by the replacement of cholesterol by omega-6 (n-6) fatty acids in many of our food products, resulting in a drastically increased ratio of omega-6/omega-3 (n-6/n-3).

New dihydroalkylhexenones from Lannea edulis.

Activity-guided isolation of radical-scavenging compounds from the dichloromethane extract of the root bark of Lannea edulis led to isolation of two known bioactive alkylphenols [cardonol 7 (1) and cardonol 13 (2)], and three new dihydroalkylhexenones were also isolated (3-5). Their structures were elucidated by spectroscopic and chemical methods. The absolute configuration of 4 was determined by the Mosher ester method.

Taxiphyllin from Henriettella fascicularis.

(2R)-alpha-(beta-D-Glucopyranosyloxy)-4-hydroxybenzeneacetonitrile (taxiphyllin) dihydrate, C(14)H(17)NO(7) x 2H(2)O, is a naturally occurring cyanogenetic glycoside which has been isolated from Henriettella fascicularis (Sw.) C. Wright (Melastomataceae).

Isolation and structure elucidation of an isoflavone and a sesterterpenoic acid from Henriettella fascicularis.

A new isoflavone, 4',5,7-trihydroxy-6,8-dimethylisoflavone (1), and a new sesterterpenoic acid (2), together with five known compounds, lichexanthone (3), (-)-pinoresinol (4), betulinic acid, palmitic acid, and beta-sitosterol, were isolated from a dichloromethane extract of the branches of Henriettella fascicularis. Their structures were established by extensive spectroscopic methods. An attempt to determine the absolute stereochemistry of (2E,6S)-6-[(1R,5Z,3aS,9R,10Z,12aR)-1,2,3,3a,4,7,8,9,12,12a-decahydro-9-hydroxy-3a,6,10-trimethylcyclopentanocycloundecen-1-yl]-2-methylhept-2-enoic acid (2) was performed by single-crystal X-ray analysis, using Cu Kalpha radiation.

Complete LC/MS analysis of a Tinnevelli senna pod extract and subsequent isolation and identification of two new benzophenone glucosides.

The hydroalcoholic extract of Tinnevelli senna is widely used as a laxative phytomedicine. In order to improve the knowledge of the chemical composition of this extract, LC/MS and LC/MS(n) studies were performed, allowing the on-line identification of most of the known constituents, i. e.

Prenylated isoflavonoids from the root bark of Erythrina vogelii.

Four new prenylated isoflavonoids, vogelins D-G (1-4), were isolated from the CH2Cl2 extract of Erythrina vogelii root bark in addition to the known compounds isolupalbigenin (5), ficuisoflavone (6), ulexone (7), isochandalon (8), and isoderrone (9). The structures 1-4 were elucidated by spectroscopic and chemical methods. The absolute configuration of compound 1 was determined on the basis of its CD spectrum.