Enhancement of health-beneficial compounds of sunflower sprouts using selected elicitors

Abstract

Sunflower sprouts are an excellent source of beneficial health compounds. This study investigated improvement of the health-promoting properties of sunflower sprouts using stressor elicitors—sucrose (25 mM, 50 mM or 100 mM), NaCl (5 mM, 50 mM or 100 mM), chitosan (0.03 mM, 0.05 mM or 0.07 mM) and salicylic acid (0.36 mM, 0.72 mM or 1.44 mM). The experiment was conducted by spraying the sunflower sprouts (1 d after sowing) with 20 ml of each treatment solution per tray in the morning for 5 d while a control group was sprayed with distilled water. The results showed that none of the elicitors significantly changed the fresh weight of sunflower sprouts. Sucrose and NaCl improved the antioxidant property of the sprouts by increasing the phenolic compounds and ascorbic acid. The highest antioxidant activity and amounts of phenolic compounds and ascorbic acid (increases by 75.67%, 43.04% and 353.15%, respectively, compared to the control) were found in the treatment involving 100 mM NaCl. The increase in phenolic compounds might have resulted from an increase in the phenylalanine ammonia-lyase activity. The highest flavonoid and γ-aminobutyric acid contents (increases by 85.63% and 264.66%, respectively, compared to the control) were obtained following the 0.07 mM chitosan treatment. Salicylic acid had the most influence on the protein content in the sprouts (the content was up to 65.39% compared to the control). This research indicated that the pre-harvest application of selected elicitors could increase the nutritional value of sunflower sprouts while limiting yield losses.