Germination of tartary buckwheat at various light strengths to enhance flavonoid content and scale-up of the process using smart-farm systems

Abstract

This study evaluated the relationship between light strength and bioactive compounds in Tartary buckwheat sprouts during germination and growth to establish smart-farm conditions for the mass production of sprouts. Tartary buckwheat (Fagopyrum tataricum Gaertner) was used in this study because of its high bioactive compound content. Tartary buckwheat sprouts were germinated and grown under different light intensities. The contents of rutin and other flavonoids increased at light intensities up to 6,000 lux. The total flavonoid and polyphenol contents and antioxidant activity were highest at 10,000 lux. However, the anti-glycemic and anti-cholesterol activities displayed different trends to that of the flavonoid content. Nevertheless, 6,000 lux was determined to be the optimal condition for flavonoid content. However, the light intensity of the smart-farm system is much lower, and the humidity is not controlled. Therefore, a 6,000 lux light intensity is not feasible at the industrial scale. The optimal germination conditions that did not affect the flavonoid contents were re-established for the scale-up of Tartary buckwheat sprout production using the smart-farm system considering the yield, productivity, and prevention of fungal contamination. These were 600 g Tartary buckwheat per germination plate, a 5° slope, and no chlorine sterilization at 200 lux light intensity.