Occurrence of 28‐ and 27‐Carbon ecdysteroids and sterols in developing worker pupae of the leaf‐cutting ant <i>acromyrmex octospinosus</i> (reich) (hymenoptera, formicidae: Attini)

Abstract

Abstract The major ecdysteroids in large worker pupae of the leaf‐cutting ant Acromyrmex octospinosus were characterized at the peak ecdysteroid concentration by using high‐performance liquid chromatography, enzyme immunoassay, and mass spectrometry. In decreasing amounts, they were determined to be makisterone A, an unidentified C 28 ecdysteroid bearing a molecular weight of 494, 20‐hydroxyecdysone (ratio of 1 to 6 as compared to makisterone A), and putative but negligible ecdysone. The presence of both C 28 and C 27 ecdysteroids is discussed in relation to the content of 4‐desmethylsterols determined by gas chromatography and mass spectrometry to be ergosta‐5,7,24 (28)‐trien‐3β‐ol, ergosterol, ergosta‐5,7‐dien‐3β‐ol and ergosta‐7,24(28)‐dien‐3β‐ol for the main sterols, and with a small amount of cholesterol.