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Trace sterols in the seeds of foxtail millet (Setaria italica Beauv.) were investigated by GC-MS. Eleven of these trace sterols, i.e., brassicasterol, episterol, 24-methyllathosterol, 24-ethyllathosterol, avenasterol, 24-methylenecholesterol, fucosterol, isofucosterol, 24-methyl-5α-cholest-24(28)-en-3β-ol, 24-ethyl-5α-cholest-24(28)Z-en-3β-ol, and 24-ethyldesmosterol, were identified, suggesting that the previously reported high content of sitostanol was possibly contaminated with a small amount of isofucosterol.

Today, consumers meet abundant supply of functional foods with plant stanol increments for serum cholesterol lowering purposes. However, efficacy and safety of plant stanols intake beyond 4 g/day have remained unexplored. We evaluated the effects of very high daily intake of plant stanols (8.8 g/day) as esters on cholesterol metabolism, and serum levels of plant sterols and stanols. In a randomized, double-blind, parallel study of 49 hypercholesterolemic subjects (mean age 62 years, range 41–73) consumed a test diet without (control, n = 24), and with added plant stanol esters (staest, n = 25) over 10 weeks followed by 4 weeks on home diet. Serum lipids, lipoprotein lipids, and non-cholesterol sterols were determined at baseline, during intervention, and 4 weeks afterwards. Cholesterol precursor sterol lathosterol reflected cholesterol synthesis, and serum plant sterols and cholestanol mirrored cholesterol absorption. When compared with controls, 8.8 g/day of plant stanols reduced serum and LDL cholesterol by 12 and 17% ( P < 0.01 for both). Synthesis marker lathosterol was increased by 30%, while absorption markers decreased up to 62% when compared with controls ( P < 0.001 for both). Serum plant stanols increased slightly, but significantly compared with controls (serum sitostanol during intervention, controls: 16 ± 1 μg/dL, staest: 37 ± 2 μg/dL, serum campestanol during intervention, controls: 0.5 ± 0 μg/dL, staest: 9 ± 1 μg/dL, P < 0.001 for both). Changes in serum cholesterol, non-cholesterol sterols, and plant stanols were normalized during post-treatment weeks. Serum plant stanol levels remained at comparable low levels as in studies with daily intake of 2–3 g, and were normalized in 4 weeks suggesting that daily intake of 8.8 g of plant stanols might not increase systemic availability of plant stanols, but reduces effectively serum cholesterol and plant sterol levels. [ABSTRACT FROM AUTHOR]

Oxidative degradation of cholesterol has been extensively researched, however, not all products formed have been established. When a phytosterols standard was heated at 60, 120 and 180 °C for different period of time the following groups of components were detected: oxidized phytosterols, fragmented phytosterol molecules, volatile compounds and oligomers. Taking into account all the components formed, we were able to balance the amounts of disappearing sterols with components formed. We established that the amount and type of products formed during thermo-oxidative degradation is affected by temperature and time. The amount of intact phytosterols decreased when temperature and time increase. The amount of oxidized phytosterols was at the highest level when a temperature of 120 °C was applied, whereas the lowest amounts were observed when a temperature of 60 °C was used. At a temperature of 180 °C the amount of oxidized sterols was lower than at 120 °C and it decreased when the heating time was increased. This indicates that oxidized sterols were the main precursors involved in the formation of other components during thermo-oxidative degradation. The amount and type of volatile compounds formed increased when time and temperature increased. We observed diversified groups of volatile compounds formed and most of them are defined as off-flavor compounds for rancid oils. [ABSTRACT FROM AUTHOR]

Plant sterol and stanol esters have been introduced as an additional dietary means to lower serum total and LDL cholesterol concentration. In short-term studies they lower LDL cholesterol by 10%, and according to a meta-analysis by Malcolm Law the incidence of coronary heart disease is considered to be reduced by over 20% in long-term use of these products. Plant stanol and sterol esters are not identical sterols; they have different metabolic effects and their long-term efficacy seems to be different. The present review deals with the differences of the sterols and discusses what is known of their role in preventing the cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effects of gender, apolipoprotein E phenotype and cholesterol absorption and synthesis (estimated as serum plant sterol and cholesterol precursor sterol concentrations) on the cholesterol-lowering effect of plant stanol esters in children.Methods: Eighty-one healthy, normocholesterolaemic 6-y-old children (45 boys) were recruited from the Special Turku Coronary Risk Factor Intervention Project (STRIP), a randomized prospective trial aiming at atherosclerosis prevention in childhood. This placebo-controlled, double-blind, cross-over study comprised two 3-mo study periods and a 6-wk wash-out period. During the study periods, 20 g of the children's daily dietary fat intake was replaced with plant stanol ester margarine or control margarine.Results: In boys, plant stanol esters reduced serum total and low-density lipoprotein cholesterol concentrations by 6% (0.09 to 0.42 mmol/L) and 9% (0.09 to 0.36 mmol/L), respectively (p < 0.01 for both). In girls, the decreases in concentrations were 4% (0.03 to 0.38 mmol/L) and 6% (0.02 to 0.32 mmol/l) (p < 0.05 for both). The response rate did not differ between the genders. Serum total and low-density lipoprotein cholesterol concentrations decreased by 6% and 8% (p < 0.01 for both), respectively, in both children with the apolipoprotein E 3/4 or 4/4 (apoE4+) phenotype and the apolipoprotein E 2/3 or 3/3 (apoE4-) phenotype. Cholesterol absorption decreased both in the apoE4+ children and in the apoE4- children, but cholesterol synthesis consistently increased in the apoE4+ children only.Conclusion: Plant stanol esters reduce serum cholesterol concentration in healthy children irrespective of their gender or apoE4 phenotype. [ABSTRACT FROM AUTHOR]