Find in Library

Similar to animals, it has recently been proven that nitro-fatty acids such as nitro-linolenic acid and nitro-oleic acid (NO₂-OA) have relevant physiological roles as signalling molecules also in plants. Although NO₂-OA is of great therapeutic importance, its presence in plants as a free fatty acid has not been observed so far. Since <i>Brassica napus</i> (oilseed rape) is a crop with high oleic acid content, the abundance of NO₂-OA in its tissues can be assumed. Therefore, we quantified NO₂-OA in <i>B. napus</i> seeds and differently developed seedlings. In all samples, NO₂-OA was detectable at nanomolar concentrations. The seeds showed the highest NO₂-OA content, which decreased during germination. In contrast, nitric oxide (&#8226;NO) levels increased in the early stages of germination and seedling growth. Exogenous NO₂-OA treatment (100 &#181;M, 24 h) of <i>Brassica</i> seeds resulted in significantly increased &#8226;NO level and induced germination capacity compared to untreated seeds. The results of in vitro approaches (4-Amino-5-methylamino-2&#8242;,7&#8242;-difluorofluorescein (DAF-FM) fluorescence, &#8226;NO-sensitive electrode) supported the &#8226;NO liberating capacity of NO₂-OA. We observed for the first time that <i>Brassica</i> seeds and seedlings contain free NO₂-OA which may be involved in germination as an &#8226;NO donor as suggested both by the results of exogenous NO₂-OA treatment of seeds and in vitro approaches. Due to their high NO₂-OA content, <i>Brassica</i> sprouts can be considered as a good source of dietary NO₂-OA intake.