No abstract

No abstract

Red amaranth (Amaranthus cruentus) and quinoa (Chenopodium quinoa) are pseudocereals with particularly highly regarded nutritional value. Because of the high biological significance of the flavonoids and phenolic acids in these plants, qualitative and quantitative analysis has been performed by HPLC. Extracts from the seeds of two amaranth varieties (A. cruentus v. Rawa and v. Aztek) and quinoa seeds, and their sprouts grown in natural conditions and in the dark were analyzed. The main phenolic acid found both in seeds and sprouts was gallic acid. p-Hydroxybenzoic acid, vanillic acid, p-coumaric acid, caffeic acid, and cinnamic acid were also found in the seeds and pcoumaric acid, syringic acid, and ferulic acid in the sprouts. The main flavonoid found in the sprouts was rutin. Vitexin, isovitexin, and morin were also detected in the sprouts, and orientin, vitexin, isovitexin, morin, and traces of hesperidin and neohesperidin in the seeds. Although sprouting conditions (daylight or darkness) had no effect on gallic acid content, light caused an increase in the amount of rutin and darkness resulted in increased amounts of isovitexin and vitexin.

This review is focused on the comparison of the biological and pharmacological activities of usnic acid enantiomers. Most of the available data refer to (?)-usnic acid, while the left-handed isomer has been less often significantly studied. Special attention was paid to the experiments comparing both (?)-and (-)-usnic acid at the same time, the results of which indicated interesting differences, however no tendency as to which enantiomer was more potent could be observed. Nevertheless, more studies, especially on (-)-usnic acid, are needed to give a final explanation for the similarities and differences between both usnic acid enantiomers. These should be especially directed to steric structure-activity relationship of the enantiomers, tested under the same experimental conditions, which may help to explain the possible mechanisms of their actions.

No abstract