A study on tansy chemotypes

Area of Science:

• Plant chemistry
• Chemical ecology
• Organic chemistry

Background:

• Chemotypes, or chemical races, can be defined by a single main component or the entire chromatogram profile.
• Previous research has shown distinct chemotypes, such as camphor and thujone, can be further subdivided (e.g., thujone A and B).

Purpose of the Study:

• To investigate the chemotype distribution in the progeny of artificial crosses of tansy (TANACETUM VULGARE L.).
• To identify and characterize the main chemical components defining these chemotypes.
• To report the first identification of germacrene-D in tansy essential oil.

Main Methods:

• Artificial crosses were performed using tansy (TANACETUM VULGARE L.).
• Essential oils from the progeny were analyzed using gas chromatography to determine peak distribution and identify main components.
• Chemotypes were classified based on the concentration of the main component and overall chromatogram profiles.

Main Results:

• Eighty percent of the progeny exhibited "well-defined chemotypes" with main component concentrations ranging from 41-99%.
• These "well-defined chemotypes" were categorized into eight main groups: sabinene, thujone, umbellulone, camphor, bornyl acetate, alpha-pinene, 1,8-cineole, and germacrene-D.
• Germacrene-D, a sesquiterpene, was identified in tansy essential oil for the first time.
• Most "well-defined chemotypes" were further divided into subgroups A and B.
• Twenty percent of the progeny presented as "mixed chemotypes".

Conclusions:

• Artificial crosses of tansy yield a high proportion of progeny with well-defined chemotypes, indicating genetic control over essential oil composition.
• The identification of germacrene-D expands the known chemical diversity of tansy essential oil.
• The subdivision of chemotypes into subgroups suggests complex genetic regulation of secondary metabolite production in tansy.