Abstract
Kaentawan (Helianthus tuberosus L.) is an important tuberous crop accumulated high content of inulin and fructo-oligosaccharides (FOS) which are currently used as prebiotics in various food products. The aims of this research were to induce microtubers of Kaentawan under in vitro condition and study of photoperiod and storage temperature effects on inulin and FOS accumulation in obtained microtubers. The microtubers were induced on tuber induction medium with some modifications. Microtubers induced under long day photoperiod (16h light/ 8h dark (LD)) and darkness (D) condition gave higher fresh weight than those induced under short day photoperiod (8h light/ 16h dark (SD)). The different applied photoperiods had an effect to inulin and FOS production in microtubers. High amount of inulin was determined in LD induced microtubers while FOS (nystose and 1- kestose) was highly produced in microtobers induced under SD and D conditions. In addition, inulin content of LD induced microtubers storing in low temperature (4ºC) for 15 days was degraded into FOS and sucrose while the inulin and FOS contents of SD and D induced microtubers was unchanged. These results gave an advantage for inulin and FOS production by means of plant organ cultures.
