Enhancement of flavonoid production of Gynura procumbens (Lour.) merr adventitious roots in baloon-type bubble bioreactor influenced by phenylalanine and tyrosine

Flavonoids are the most commonly found compounds in Gynura procumbens (Lour.) Merr. The biosynthesis of flavonoid is induced by several precursors. Phenylalanine and tyrosine are flavonoid precursors via the shikimate pathway before condensing with the malonic acetate pathway. The aim of this research is to enhance flavonoid production of G. procumbens adventitious roots influenced by phenylalanine and tyrosine. This research was conducted by planting the adventitious root explants in MS liquid medium supplemented with IBA 5 mg/L IBA and various concentration of phenylalanine (0.50, 100 and 200 mg/L) and tyrosine (0.50, 100, and 200 mg/L). Adventitious roots were cultured in a balloon-type bubble bioreactor (1L capacity and working volume 500 mL). The cultures were maintained for 28 days in the dark. Flavonoid compounds (kaempferol and quercetin) were detected by spectrophotometer. The results show that supplementation of phenylalanine 200 mg/L could increase kaempferol (2233.33 mgL^-1/g dry weight) and quercetin (6150.00 mgL^-1/g dry weight), while supplementation of tyrosine also could increase kaempferol (1866.67 mgL^-1/g dry weight) and quercetin (5050.00 mgL^-1/g dry weight). The results of this study can be used as a basis for determining strategies on a large scale.