Malcolm J. Thompson

Chemical composition of the culture form of Trypanosoma cruzi.

Abstract 1. 1. The culture form of T. cruzi contains considerably more lipids than carbohydrates. 2. 2. No glucose polysaccharide was found. A galactose-containing polysaccaride was observed but it could not be separated from nucleic acid derivatives. 3. 3. The nature of the nucleic acid derivatives indicated that T. cruzi contains both deoxyribonucleic acid and ribonucleic acid, the latter representing in part at least the volutin granules. 4. 4. A large part of the unsaponifiable fraction consists of cholesterol. The presence of a small amount of a 5,7-diene was indicated by ultraviolet spectroscopy.

Techniques for the isolation and identification of steroids in insects and algae

Analytical techniques, methods and instrumentation employed for the extraction, isolation separation, purification and identification of steroids from algae and insects are presented. The techniques include adsorption and argentation column chromatography and counter-current distribution for separating the individual steroids, and thin layer chromatography and gas liquid chromatography for monitoring the purification process. Double bond, steric and alkyl substituent separation factors and relative retention times are reported for a large number of sterols on 4 different column systems. Their use permits the tentative structural assignment of sterols. Ultraviolet, infrared, nuclear magnetic resonance (NMR) and mass spectral analyses are discussed in light of their significance in the isolation and identification of steroids from insects and algae. Numerous examples are presented, including the use of 220 MHz NMR spectrometry, which permits the differentiation and characterization of C-24 epimetric sterols and allows for a semiquantitative estimate of the 24α- and 24β-epimers present in a mixture.

Unsaponifiable lipids of Taenia taeniaeformis and Moniezia sp.

The experiments presented above show that in Taenia taeniaeformis and in Moniezia sp. cholesterol is by far the most prevalent unsaponifiable substance. In the former tapeworm it amounted to at least 98% of total unsaponifiable material, in the latter to approximately 85%. The fact that a search for friedelin in Taenia taeniaeformis was negative strengthens the assumption by Cmelik and Bartl, 1956 that the friedelin found in Taenia saginata did originate from cork stoppers. n nOur finding of 7-ketocholesterol in the Moniezia sample requires a comment. It is known that hot alkaline saponification of 7-ketocholesterol ester produces cholesta-3, 5-diene-7-one.3Milburn et al., 1956Mauthner and Suida, 1896. Since the latter compound was not present in our sample, it may be concluded that the 7-ketocholesterol was not originally present, but was formed during isolation and storage of the unsaponifiable material4 from the Moniezia sp. No trace of 7-ketocholesterol could be isolated from the unsaponifiable material of the Taenia taeniaeformis.