Effect of elicitation with sodium silicate and iron chelate on the composition and quality of fatty acids in buckwheat sprouts

In laboratory experiments, the impact of elicitation with a mixture of sodium silicate and iron chelate or sodium silicate alone on fatty acid composition in sprouts of common buckwheat (Fagopyrum esculentum Moench) has been examined. Buckwheat seeds and then sprouts were soaked for 0.5 h each day over six days in an aqueous solution of the mentioned elicitors. The sprouts were grown in the light regime of 16/8 h, day/night. After seven days of germination (sprouting), the composition of fatty acids in freeze-dried and powdered sprout tissues was analyzed by gas chromatography. The results showed significant changes in the composition of fatty acids in sprouts in comparison to buckwheat seeds. The results indicate that the germination of buckwheat seeds leads to an increase in myristic (C14:0), palmitic (C16:0), stearic (C18:0) and behenic (C20:0) acid in sprouts, although the use of the elicitors, especially sodium silicate, inhibited this tendency. The sprouts of common buckwheat contained almost twice as much α-linolenic acid (C18:3) as the seeds did, and slightly less linoleic acid (C18:2). Moreover, the use of elicitors favored an increased accumulation of α-C18:3. As a result, germination drastically reduced the C18:2/a-C18:3 ratio by about 4 times, which may have a positive health effect. The buckwheat sprouts contained traces of eicosatrienoic (C20:3), eicosatetraenoic (C20:4), docosaenoic (C22:1) and docosadienoic (C22:2) acids, while their content in the seeds was between 0.6 and 2.4%. The buckwheat sprouts had a higher atherogenic (AI) and thrombogenic index (TI) and a lower health index (HI) than seeds did, but the use of elicitors inhibited this tendency.