phytosterols and cyclolaudenol

The leaves of Tillandsia fasciculata afforded four tetracyclic triterpenoids of the cycloartane type, two new compounds identified as cyclolaudenyl formate (2) and the (24S)-24-isopropenyl cycloartanone, which we named tillandsinone (1), and the known cyclolaudenone (3) and cyclolaudenol (4).

Topics: Gas Chromatography-Mass Spectrometry; Magnetic Resonance Spectroscopy; Mexico; Phytosterols; Plant Leaves; Plants, Medicinal; Triterpenes

To study the petroleum ether extract of Rhizoma Drynariae.. Solvent extraction silica gel column isolation, and structure elucidation by physico-chemical evidence and spectral analysis.. Three compounds were isolated and elucidated as fern-9(11)-ene, hop-22(29)-ene and cyclolaudenol.. All the three compounds are triterpenoids.

Topics: Drugs, Chinese Herbal; Phytosterols; Plants, Medicinal; Polypodiaceae; Rhizome; Triterpenes

The tetracyclic sterol precursors, cyclolaudenol, cycloartenol and lanosterol, inhibit efficiently the tetrahymanol biosynthesis in the ciliate Tetrahymena pyriformis, as reported earlier for cholesterol and other sterols. The prokaryotic bacteriohopanetetrols have little effect, and diplopterol, another hopanoid, as well as the carotenoid, canthaxanthin, have no effect. In the presence of triparanol, a hypocholesterolemic drug inhibiting the squalene cyclase of T. pyriformis and modifying the fatty acid metabolism, the cells do not grow further, but growth can be restored by the addition to the culture medium of suitable polyterpenoids. Thus, growth in presence of triparanol (13 microM) is almost normal after addition of a sterol such as sitosterol and cyclolaudenol, and longer lag times and lower absorbances than those of untreated cultures are observed in presence of cyclartenol, lanosterol, euphenol (a lanosterol isomer), bacteriohopanetetrols and three carotenoids. No growth at all is observed in the presence of tetrahymanol and diplopterol, although these triterpenoids are the normal reinforcers of the ciliate, probably because of a poor bioavailability. Thus, structurally different polyterpenoids are (at least partially) functionally equivalent and capable of replacing tetrahymanol or sterols and might act as membrane reinforcers in T. pyriformis cells.

Topics: Animals; Cholesterol; Lanosterol; Phytosterols; Polymers; Sitosterols; Squalene; Tetrahymena pyriformis; Triparanol; Triterpenes

Topics: Aerobiosis; Anaerobiosis; Cholesterol; Kinetics; Lanosterol; Phytosterols; Saccharomyces cerevisiae; Structure-Activity Relationship; Triterpenes