4863-54-1Relevant articles and documents
Oxyphytosterols as active ingredients in wheat bran suppress human colon cancer cell growth: Identification, chemical synthesis, and biological evaluation
Zhu, Yingdong,Soroka, Dominique,Sang, Shengmin
, p. 2267 - 2276 (2015)
Consumption of whole grains has been reported to be associated with a lower risk of colorectal cancer. Recent studies illustrated that phytochemicals in wheat bran (WB) may protect against colorectal cancer. There is a growing interest in the phytosterol contents of foods as either intrinsic or added components due to their beneficial health effects. However, little is known whether phytosterols in WB contribute the observed chemopreventative activity of the grain. In the present study, we directly purified and identified four oxyphytosterols 1-4 from sterol-enriched fraction of WB, and also successfully synthesized five sterol oxides 5-8 and 13. Using these nine compounds as references, we outlined a comprehensive profile of steroids in WB using tandem liquid chromatography mass spectrometry with electrospray ionization (LC-ESI/MSn, n = 2-3) techniques for the first time. Among them, three sterol oxides 13, 14, and 18 are novel compounds, and 14 compounds 3, 4, 6-11, 13, 14, 16, and 18-20 were reported in WB for the first time. Our results on the inhibitory effects of available sterol oxides 1-8 and 13 against the growth of human colon cancer cells HCT-116 and HT-29 showed that compounds 2-8 exerted significant antiproliferative effects, with oxysterol 8 being the most active one in both cells. We further demonstrated that four most active sterol oxides 5-8 could induce cell death through the apoptosis pathway. Our results showed that phytosterols, particularly oxyphytosterols, in WB possess significant antiproliferative properties, and thereby may greatly contribute the observed chemoprevention of the whole grain wheat.
Gram-scale chromatographic purification of β-sitosterol: Synthesis and characterization of β-sitosterol oxides
Zhang, Xin,Geoffroy, Philippe,Miesch, Michel,Julien-David, Diane,Raul, Francis,Aoude-Werner, Dalal,Marchioni, Eric
, p. 886 - 895 (2007/10/03)
An effective purification method for β-sitosterol was developed starting from a commercial source of a phytosterol mixture using preparative adsorption column chromatography. β-Sitosterol (≥95% purity) was obtained on a gram-scale. Thus, the synthesis of six β-sitosterol oxides, including 7α-hydroxy, 7β-hydroxy, 5,6α-epoxy, 5,6β-epoxy, 7-keto, and 5α,6β-dihydroxysitosterol, were successfully carried out. The spectral characteristics of all the synthetic intermediates and target compounds (～95% purity) were well-documented.
Mass spectrometry characterization of the 5α-, 7α-, and 7β-hydroxy derivatives of β-sitosterol, campesterol, stigmasterol, and brassicasterol
Bortolomeazzi, Renzo,De Zan, Michela,Pizzale, Lorena,Conte, Lanfranco S.
, p. 3069 - 3074 (2007/10/03)
The 5α-hydroperoxides of β-sitosterol, campesterol, stigmasterol, and brassicasterol were obtained by photooxidation of the respective sterols in pyridine in the presence of hematoporphyrine as sensitizer. The reduction of the hydroperoxides gives the corresponding 5α-hydroxy derivatives. The 7α- and 7β-hydroperoxides of the sterols were obtained by allowing an aliquot of the 5α-hydroperoxides to isomerize to 7α-hydroperoxides, which in turn epimerize to 7β-hydroperoxides. The reduction gave the corresponding 7α- and 7β-hydroxy derivatives. The 5α-, 7α-, and 7β-hydroxy derivatives of β-sitosterol, campesterol, stigmasterol, and brassicasterol were identified by comparing thin-layer chromatography mobilities, specific color reactions, and mass spectral data with those of the corresponding hydroxy derivatives of cholesterol, which were synthesized in the same manner. The phytosterols had the same behavior to photooxidation as cholesterol and, moreover, the different phytosterols photooxidized at about the same rate. The mass spectra of the trimethylsilyl ethers of the hydroxy derivatives of the phytosterols investigated and of the corresponding hydroxy derivatives of cholesterol have the same fragmentation patterns and similar relative ion abundances.
