Chang-Dae Lee, Sang-Yun Lee, Reyna Marie Therese Sanchez, Eunsol Ku, Neil Patrick Uy, Jonie Yee, Chung-Ho Choi, Sanghyun Lee
The transition from cotyledons to true leaves involves substantial metabolic changes. However, the stage-specific bioactive properties of native ornamental plants have not been thoroughly investigated. This study compared total phenolic and flavonoid contents together with preliminary biological activities of the cotyledon and true leaf stages in Lespedeza cyrtobotrya, Amorpha fruticosa, Flueggea suffruticosa, Ulmus parvifolia, Tripora divaricata, and Paulownia coreana seedlings to optimize their potential for horticultural applications. Total phenolic and flavonoid contents (TPC and TFC) of ethanol extracts were evaluated, and radical scavenging capacities were assessed using ABTS and DPPH assays. Preliminary antibacterial activities were also investigated against Staphylococcus aureus, Acinetobacter baumannii, while potential quorum sensing (QS) inhibition was tested against Chromobacterium violaceum. The transition to the true leaf stage was consistently associated with increased TPC and TFC levels, suggesting increased antioxidant potential in L. cyrtobotrya, A. fruticosa, F. suffruticosa, and U. parvifolia. In contrast, cotyledons of T. divaricata and P. coreana exhibited preliminary antibacterial and antioxidant potential that surpassed those of the true leaves. As the true leaves matured, pigment-suppression activity was observed in selected extracts, suggesting that the true leaf stage may possess potential QS inhibitory activity. These stage-dependent bioactivities provide essential baseline data for optimizing harvest timing and highlight the potential of specific seedling stages for applications in urban horticulture. © 2026 by the authors.
Chung-Ang University, Department of Plant Science and Technology, Anseong, 17546, South Korea; Department of Mathematics and Natural Sciences—Biology, Cebu Institute of Technology–University, Cebu, 6000, Philippines; Department of Biology, University of San Carlos, Cebu, 6000, Philippines; Tree Research Team, Gyeonggi-do Forestry Environment Research Center, Osan 18118, South Korea; Natural Product Institute of Science and Technology, Anseong, 17546, South Korea