Table 1. Summary of alkaloids detected in collections of Choresine beetles
Collection type (no. analyzed) BTX-A 418 BTX-A O-acetate (rearranged) 460 BTX-A O-crotonate 486 BTX 539 h-BTX 553 Other BTXs
I (29) ++-+++ +++ ++-+++ nd-++ nd-+ 514 (+-++) (2), 500 (+), 525 (+-+++), 583 (+), and others
II (5) +++ +++ +++ nd-+++ nd-+ 500 (+-++), 514 (++), 565 (+), 583 (+), 597 (+)
III (3) +++ +++ +++ 565
IV (1) ++ nd +++ +++ + 525 (++), 514 (++), 436/438 (++)
V (1) + + +++ nd nd
VI* (1) +++ +++ ++ ++ + 500 (+), 514 (+)
  • The protonated molecular ion is shown in bold. nd, not detectable; +, trace (detected with single ion profiling); ++, minor; +++, major. Contents ranged widely in different collections listed in I, II, and IV. For example, in the 29 collections reported as type I, BTX-A and BTX-A O-crotonates ranged from minor to major, BTX-A ranged from nd to minor, and h-BTX ranged from nd to trace.

  • * This collection in ethanol (17 beetles, not identified as to species) was sonicated in fresh ethanol for a 30-min period at room temperature after the initial extract had been decanted. The original and sonicated extracts were combined for analysis. The sonication step added little to the BTXs extracted.