Growth, phytochemical properties, and antioxidant activity of in vitro-gamma irradiated Tacca leontopetaloides (L.) Kuntze

Tacca leontopetaloides (L.) Kuntze, is a tuberous plant having high starch content similar to potatoes. This plant is now still under-utilized, grows limited only in some coastal area in Indonesia. In addition to their use as source of carbohydrate, secondary products of this plant are useful as anticancer. Genetic improvements of plants can be done by mutation with Gamma irradiation. In vitro shoots of Tacca have been developed after irradiation with Gamma ray. The aim of this research was to investigate growth, phytochemical properties and antioxidant activity of Tacca plantlets after Gamma irradiation treatment. Shoots were irradiated with 5, 20 and 30 Gy, then they were grown on MS medium containing 0.5 mg/l BAP or 0.5 mg/l kinetin. Growth was recorded every week from week-1 to week-8 of culture. After 8 weeks of culture, biomass production of plantlets, phytochemical properties as well as antioxidant activity were determined. The results showed that irradiated plants had slightly lower in growth compared to the control plants. However, IC50 of irradiated plants was lower than control plant. This indicated that irradiated plants had higher antioxidant activity. Addition of kinetin and BAP affected IC50 value. Irradiated Tacca has similar phytochemical properties of control plants based of alkaloid, flavonoid, steroid, saponin and tannin detection. This study showed new opportunities to produce a new superior type of T. leontopetaloides with higher antioxidant activity induced by Gamma irradiation mutation.