1. Hui-Jing GU IUFRODivision 5 Conference 5.07.00 D Forest Products / Energy and chemicals from forest biomass / Chemicals from wood

2. Hui-Jing GU, Sen-Sung CHENG, Hui-Ting CHANG and Shang-Tzen CHANG School of Forestry and Resource Conservation, National Taiwan University No. 1, Section 4, Roosevelt, Taipei, Taiwan, ROC Tel +886-2-3366-4614; Fax +886-2-3365-4520 Mosquito larvicidal activity of ethanolic extracts of Cryptomeria japonica

3. Larvicidal activity was evaluated after 24 h and 48 h treatments. Effectiveness were reported as LC50 and LC90. Aim of work and methods The purpose of this study is to determine the larvicidal activities of ethanolic extracts from leaves, wood and bark of Cryptomeria japonicaagainst fourth-instar larvae of the mosquitoes Aedes aegypti and Aedes albopictus. Plant material Mosquito larvae • Leaf • Bark • Wood Aedes aegypti Aedes albopictus Cryptomeria japonica

4. Results Cryptomeria japonica Extraction Wood extract A. aegypti（ LC50 ＝63.2 μg/mL ） A. albopictus（LC50＝93.8 μg/mL ） Bioassay Extracts Liquid-Liquid partition n-Hexane A. aegypti（ LC50 ＝ 36.5 μg/mL ） A. albopictus（LC50＝111.8 μg/mL ） Fractions Bioassay CC, TLC H5 A. aegypti（ 100% mortality ） A. albopictus （72.5% mortality ） Bioassay Subfractions HPLC epi-Cubebol Cubebol Bioassay Compounds IR, UV, MS, NMR

5. Conclusions This study demonstrated that the ethanolic extract of C. japonica wood and its major compounds have excellent mosquito larvicidal activities against both A. aegypti and A. albopictus. These result could be useful in the research for selecting newer, more selective, biodegradable and natural larvicidal agents. Thank You for Your Attention!