Optimization of Adventitious Root Culture Conditions and Airlift Bioreactor Scale-Up in Four Jeju Native Plants

Abstract

Jeju Island, a UNESCO World Natural Heritage Site, is rich in native plant diversity. However, many of these plants are underutilized due to propagation challenges and ecological sensitivity. In line with international biodiversity frameworks (CBD and ABS), this study aimed to establish an optimized in vitro adventitious root (AR) culture platform for the conservation and bioutilization of selected Jeju native plants. Extensive surveys and in vitro evaluations identified four high-performance candidates for AR induction, Calystegia soldanella (CAS), Hibiscus hamabo (HIH), Lycoris chejuensis (LYC), and Tetragonia tetragonoides (TET). We systematically optimized culture conditions, finding that Murashige and Skoog (MS) media and specific auxin treatments (IBA and NAA) enhanced rooting efficiency. The most responsive cultures were scaled up in 5 L airlift bioreactors. Biomass performance was quantified by various metrics, including growth index and relative growth rate. CAS and HIH showed superior proliferation, yielding over 30 g DW·batch-1 with a relative growth rate above 3.0. This study successfully optimized a bioreactor-based AR culture platform, demonstrating its technical and biological feasibility for both ex situ conservation and industrial-scale bioproduction. The platform provides a scalable, ESG-aligned model for the genetic preservation and sustainable valorization of Jeju’s unique botanical resources within the emerging bioeconomy.