Phytosterols p-sitosterol

From a precursor spiking experiment involving addition to tobacco of aliphatic tobacco hydrocarbons, a phytosterol (P-sitosterol), or solanesol, it was noted that the increase in the chrysene yield in the CSC was much more pronounced with phytosterol-treated tobacco than with aliphatic hydrocarbon-or solanesol-treated tobacco (3251, 3269, 3291). Doubling the levels of solanesol, aliphatic tobacco hydrocarbons, and phytosterols by addition of each to a control tobacco blend resulted in increases in the B[a]P yields in the mainstream CSCs of 13%, 13%, and 16%, respectively. However, the chrysene yields were increased by 16%, 28%, and 183%, respectively. Tripling the addition levels increased the B[a]P levels in the mainstream CSCs by 18%, 20%, and 28%, respectively, and the chrysene levels by 22%, 50%, and 239%, respectively. 

There is an increasing interest in the lipid characteristics of nut oils as they seem to be an interesting source of bioactive constituents and functional ingredients [170,174,187]. Among tree nuts, hazelnut has many beneficial health attributes and is among three most popular and commonly consumed tree nuts in Europe [188] and other Western populations [179]. The benefits of hazelnut inclusion into the human diet is partly related to its fat components (around 60%), most of which are highly rich in MUEA (primarily oleic acid), tocols (a-tocopherol), phytosterols (p-sitosterol), polyphenols, and squalene [10,12,99,104,117,160,170,189]. 

In the Kf- range from 0.60 up to =0.80 appear with yellow brown colour linoleic acid (T3), oleic acid (T5) and the phytosterol P- sitosterol (T2). Saccharose was identified at iy=0.16 (T4). In the Rf- range Rf= 0.15 till Kf= 0.50 the three dark brown and pink brown spots might be identical with mono-, di- and triglycoside of sesaminol. 

Sterols are minor constituents of most fats. Those of animal origin contain cholesterol and traces of other sterols, whereas plants contain phytosterols, of which p-sitosterol is the most common. Sterols occur in the free form or, after esterification to fatty acids through the 3-OH group, as steryl esters. The presence of sterols in archaeological residues can be a useful indicator of a plant or animal origin or an indicator of both if cholesterol and phytosterols are detected in the same sample. That noted, cholesterol is a potential contaminant of all archaeological samples subjected to handling. 

P-Sitosterol-3-O-P-D- glucoside (phytosterol glycoside) Widespread Caryophyllus Jlos (Myrtaceae) PEP (48 pM) [118]... 

Canola oil contains a relatively high level of phytosterols (892 mg/100 g), about twice the level in soybean oil or sunflower oil (436 and 496 mg/100 g respectively) (Table 8). p-Sitosterol accounts for about 50%, campesterol 35%, and brassicasterol 14% of the total phytosterols in canola oil. Canola oil is the only common vegetable oil that contains brassicasterol. Plant sterols have been reported to lower plasma cholesterol level (107) by inhibiting the absorption of dietary cholesterol and the reabsorption of biliary cholesterol (108). 

Sterols or phytosterols are present in flax oils at a level lower than those in many vegetable oils, 2.3 mg/g in flaxseed oil versus 4.1 to 6.9 mg/g in other oils (Table 2). The composition of sterols was similar to other oils, where p-sitosterol was the main component followed by campesterol and A -avenasterol. Brassicasterol was found in trace amounts in flax oil. This phytosterol is characteristic to plants from the Brassica family and often is used as a marker for oil adulteration (Table 2). 

Phjdosterols and cholesterol have similar structures phytosterols are therefore competitors of cholesterol absorption. Consumption of phytosterol may lower blood cholesterol and thus protect from cardiovascular diseases (29). Phytosterol, especially, p-sitosterol, inhibits the growth of human colon cancer cell (30), prostate cancer cell (31), and breast cancer cell (32). 

The proximate composition of almond includes 50.6% lipid, 21.3% protein, 19.7% carbohydrate, 5.3% water, and 3.1% ash (w/w) (1). The most common method for producing almond oil is hexane extraction that affords high oil yields, however, cold pressing is another commercially used procedure for almond oil production (8). Shi et al. (8) assessed the fatty acid composition of almond oil oleic acid was major fatty acid present (68%), followed by hnoleic acid (25%), palmitic acid (4.7%), and small amounts (<2.3%) of palmitoleic, stearic, and ara-chidic acids (Table 1). Almond oil is also a rich source of a-tocopherol (around 390 mg/kg) and contains trace amounts of other tocopherol isomers as well as phyl-loquinone (70pg/kg) (1). Almond oil contains 2.6g/kg phytosterols, mainly p-sitosterol, with trace amounts of stigmasterol and campesterol (1). 

The fatty acid composition of hazelnut oil is as follows 78-83% oleic acid, 9-10% linoleic acid, 4—5% palmitic acid, and 2-3% stearic acid as well as other minor fatty acids (Table 3) (1, 22). Parcerisa et al. (23) examined lipid class composition of hazelnut oil, showing that triacylglycerols constituted 98.4% of total lipids, glycolipids comprised 1.4% of total hpids, and trace amounts (<0.2%) of phosphatidylcholine and phosphatidylinositol were also present. Hazelnut oil contains 1.2-1.14 g/kg of phytosterols primarily in the form of p-sitosterol and is a very good source of a-tocopherol (382-472 mg/kg) (1, 22). The main odorant in... 

Walnuts contain about 65% lipids, however, considerable differences exist among varieties (range 52-70%, w/w) (1,40). Walnuts also contain 15.8% protein, 13.7% carbohydrate, 4.1% water, and 1.8% ash (w/w) (1). The fatty acid composition of walnut oil is unique compared with other tree nut oils for two reasons walnut oil contains predominantly linoleic acid (49-63%) and a considerable amount of ot-linolenic acid (8-15.5%). Other fatty acids present include oleic acid (13.8-26.1%), palmitic acid (6.7-8.7%), and stearic acid (1.4—2.5%) (Table 5) (40). The tocopherol content of walnut oil varies among different cultivars and extraction procedures and ranges between 268 mg/kg and 436 mg/kg. The predominant tocol isomer is y-tocopherol (>90%), followed by a-tocopherol (6%), and then (3- and 8-tocopherols (41). Nonpolar lipids have been shown to constitute 96.9% of total lipids in walnut oil, whereas polar lipids account for 3.1%. The polar lipid fraction consisted of 73.4% sphingolipids (ceramides and galactosylcera-mides) and 26.6% phospholipids (predominantly phosphatidylethanolamine) (42). Walnut oil contains approximately 1.8g/kg phytosterols (1), primarily p-sitosterol (85%), followed by A-5-avenasterol (7.3%), campesterol (4.6%), and, finally, cholesterol (1.1%) (42). 

Presence of phytosterols in oat oil was first reported by Idler et al. in 1953 (128). Oat grain contains 35-60 mg phytosterols/100 g grain (127). Phytosterol content of oat oil varies between 0.19% to 0.32% (125). p-Sitosterol (40-70% of total sterols) is the major phytosterol in oats. A - and A -Avenasterol are the two other phytosterols that present in significant quantities in oats. Campesterol, stigmasterol, A -stigmasten-3p-ol, A -cholesten-3p-ol, and cholesterol were also present in oat grain. 

Tlie bioconversion of steroids, tire products of which are used in steroidal hormone pharmaceuticals, is carried out at a scale of more tlian 1000 tons/year- starting from natmal phytosterols from soya, conifers and from rape seed (P-sitosterol, campesterol, stigmas-terol, brassicasterol, and P-sitostanol). 

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