Flavone C-glycosides, phenolic acids and nitrogen content in leaves of barley subject to organic fertilization treatments

Summary

From the leaves of barley, Hordeum vulgare, one new flavone C-glucoside and three known flavone glucosides were isolated and characterized by 1H, 13C NMR and MALDITOF-MS. The novel flavone C-glucoside was isovitexin 7-O-b-(6’’’-O-(E)-p-coumaroyl)glucoside and the known compounds were isovitexin 7-O-b-(6’’’-O-(E)-feruloyl)glucoside, isoorientin 7-O-b-(6’’’-O-(E)-feruloyl)glucoside and tricin 7-O-b-glucoside. The sum of all the flavone glycosides and soluble phenolic acids in the leaves decreased with increased rate of plant nutrients given in animal manure and with increased crop yield. All major phenylpropanoids showed the same general response to nutrient level. The concentration of nitrogen in the leaves was not directly related to nutrient application nor to contents of phenylpropanoids.