Sesquiterpene lactones bioassays

Quantitative analysis of feverfew with regards to sesquiterpene lactone content has been carried out by TLC [72,73] and HPLC [71,74,75] and H-NMR spectroscopy [75]. Measurements of parthenolide by HPLC correlated well with measurements by bioassays based on 5HT-secretion from platelets [75]. The availability of several techniques for quantitation of parthenolide levels in feverfew, makes some standardization of commercial preparations possible. 

Figure 3. Sesquiterpene lactones used in the insect bioassays.

Bioassay-guided fractionation of the antimicrobial dichloromethane extract from Xanthium spinosum L. yielded xanthatin, Fig. (22) [194]. This compound was active against Colletotrichum gloesporoides, Trichotecium roseum. Bacillus cereus and Staphylococcus aureus. These compounds together with another sesquiterpene lactone xanthinin, Fig. (23) were also isolated from Xanthium italicum Moretti [195]. 

Following a report that male P. hybneri were attractive to both sexes [99], males were found to produce a mixture containing the sesquiterpene 6-sesquiphellandrene, (R)- 15-hexadecanolide 114, and methyl (Z)-8-hexade-cenoate [100]. Odors from live males were attractive to adults of both sexes, with males also becoming sexually stimulated. Each component alone had some slight activity, with the 3-component blend being the best attractant in laboratory bioassays. The (S)-enantiomer of the macrolide lactone component was not inhibitory. 

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