●Year. Month. Day-Day Place, Country, Convention, Title

●1996.11.27-29 Bangkok, Thailand
NRCT-JSPS Core University system, The third joint seminar
"Current advances in natural product research"
Special Lecture: "Constituents of Philippine Boraginaceae Plants"(Abstract)

●1997.8.12-8.15 Kunming, China
International Symposium on Plant Glycosides
Plenary Lecture: "Non cyanogenic cyanoglucosides"(Abstract)

●1998.9.24-28 Hanoi, Vietnam
The ninth Asian symposium on medicinal plants, spices and other natureal products
Symposium Lecture: "Anti-tumor-promoting activity of majonoside-R2 - a triterpene saponin from Vietnamese Ginseng (Abstract)

●1999.12.1-2 Bangkok, Thailand
IOCD-International symposium as satellite meeting of The fourth Princess Chulabhorn Science Congress, Chemistry and pharmacology of Asian plants and validation of phytopharmaceuticals
Plenary lecture: "Bioactive saponin in Vietnamese ginseng, Panax vietnamensis"(Abstract)

●1999.12.6-.8 Quezon City, Philippines
Joint 4th Annual convention of the Natural Products society of the Philippines and 21st annal convention of the Philippine environmental mutagen society
Plenary lecture: "Antiallergic and antidiabetic compounds from some Philippine medicinal plants"(Abstract)

●2000.10.24-25 Selangor, Malaysia
16th National Seminar on Natural Products
"Interdisciplinary Approaches in Natural Products Research"
Plenary Lecture: "Phytochemical and biochemical study on bioactive saponins in Vietnamese ginseng, Panax vietnamensis"(Abstract)

●2001.6.5-7 Depoc, Indonesia
International Seminar on Natural Product Chemistry and Utilization of Natural Resources
Plenary lecture: "Activators of Glucose Transporter in Lagerstroemia speciosa
--Possible Hypoglycemic Constituents from Banaba--"

●2002.3.4 Bangkok, Thailand
Special Lecture at the Ministry of Public Health
Improvement of the sweetness of stevia glycosides (One of the slides)

●2002.11.29 Seoul, Korea
The 8th International Symposium on Ginseng
Invited Lecture: "Metabolism of Ginseng Saponins and its Significance" (Abstract)