Callus induction of red ginger (Zingiber officinale var. rubrum) with 2,4-D and Kinetin combination to enhance total phenolic and flavonoid content

Plant tissue culture perform as in vitro technique which use any parts of plants under
environmental and nutritional control. Tissue culture provides a competitive systems for
effective secondary metabolites production, including in red ginger which has many functional
properties with high demand in health and pharmaceutical sectors. This study aims to develop
an appropriate procedure to cultivate red ginger with in vitro technique to enhance its phenolic
and flavonoid content. The rhizome buds were use as explants for callus induction by MS
medium with some combination of 2,4-D and kinetin (1:0; 1:1; 1:5; and 5:1). The 70% ethanol,
5,25% sodium hypochlorite, and 10% povidone iodine were used for surface sterilization of bud
explants. The result reveals that in 1:0 combination of 2,4-D and Kinetin, the compact callus
were initiated on day-16. The other three combinations showed shorter callus forming time in
day-14 and they were friable. The 1:1 combination showed the highest percentage (70%) of
callus formation compared to other three combinations. In this combination also indicated no
contamination occurs. From this in vitro tissue culture, the methanolic extract of callus obtained
highest total phenolic content (204,793 µg/mL) than rhizome (130.77 µg/mL). Though, the total
flavonoid content of callus extract (0,289 µg/mL) was lower than rhizome extract (6.74 µg/mL).
This study showed that the in vitro tissue culture was quite appropriate to enhance total phenolic
content in red ginger, although not at the flavonoid content.