Hiroshi Goto1, Toyonobu Usuki. 1. Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, Chiyoda-ku, Tokyo, 102-8554, Japan.
Abstract
INTRODUCTION: Terpene trilactones (TTLs), unique components of Ginkgo biloba extracts, are believed to play important roles in the biological activity of these materials. The investigation of seasonal and gender-related variations in the natural content of TTLs in the leaves is a challenging problem that must be addressed in order to establish more efficient extraction/isolation protocols for TTLs. OBJECTIVE: The aims of this work were (i) to modify the extraction/isolation protocols of TTLs from G. biloba leaves by means of boiling and filtration procedures, and (ii) to investigate seasonal and gender-related variations in the TTL content of the leaves via (1) H-NMR analysis. METHODOLOGY: When extracting TTLs from G. biloba leaves, procedures for boiling and filtration were improved in this work. Moreover, quantitative (1) H-NMR analysis using DMF as a reference was performed and correlated to the colour (green/yellow) and gender (male/female) variations in the natural compositions of TTLs in the leaves. RESULTS: Extraction procedures were modified to include boiling in ethyl acetate and filtration was achieved with celite. (1) H-NMR analysis of TTLs suggested that green female leaves contained the largest amount of TTLs, while no TTLs were present in yellow male leaves. CONCLUSION: The present results provide a method for quickly supplying laboratory-scale quantities of TTLs from natural sources to enable the study of their structure-activity relationships.
INTRODUCTION:Terpene trilactones (TTLs), unique components of Ginkgo biloba extracts, are believed to play important roles in the biological activity of these materials. The investigation of seasonal and gender-related variations in the natural content of TTLs in the leaves is a challenging problem that must be addressed in order to establish more efficient extraction/isolation protocols for TTLs. OBJECTIVE: The aims of this work were (i) to modify the extraction/isolation protocols of TTLs from G. biloba leaves by means of boiling and filtration procedures, and (ii) to investigate seasonal and gender-related variations in the TTL content of the leaves via (1) H-NMR analysis. METHODOLOGY: When extracting TTLs from G. biloba leaves, procedures for boiling and filtration were improved in this work. Moreover, quantitative (1) H-NMR analysis using DMF as a reference was performed and correlated to the colour (green/yellow) and gender (male/female) variations in the natural compositions of TTLs in the leaves. RESULTS: Extraction procedures were modified to include boiling in ethyl acetate and filtration was achieved with celite. (1) H-NMR analysis of TTLs suggested that green female leaves contained the largest amount of TTLs, while no TTLs were present in yellow male leaves. CONCLUSION: The present results provide a method for quickly supplying laboratory-scale quantities of TTLs from natural sources to enable the study of their structure-activity relationships.
Authors: Kwang Ho Lee; Jung Kyu Kim; Jae Sik Yu; Se Yun Jeong; Jin Hee Choi; Jin-Chul Kim; Yoon-Joo Ko; Seon-Hee Kim; Ki Hyun Kim Journal: Arch Pharm Res Date: 2021-04-30 Impact factor: 4.946