introduction of phytosterols and their health benefits. how it does help in promoting good cholestrol in body and preventing from CVD and other major diseases. How it should take in diet. recent researches at phytosterols.

1. PHYTOSTEROLS
SAIQA AMJAD
BS Food Science and Technogy
GCWUF

2. Phytosterols
Phytosterols is define as “Collective term of plant-derived sterols and stanols” derived from Greek
word “phyton” means plant and “stereos” means solid. Phytosterols are typically plant origin and
cannot be synthesized by human beings, therefore their source in human body originates only from
diet. The richest naturally occurring sources of phytosterols are vegetable oils and their products.
Nuts are rich in phytosterols, are often eaten in smaller amounts, but they have significant
contribution to total phytosterol intake. Sources of phytosterols also include fat-soluble fractions
of seeds, roots, stems, branches, leaves and blossoms. They are constituents of both edible and
ornamental plants, including herbs, shrubs and trees. Commercially, phytosterols are extracted
from vegetable oils, such as soybean oil, rapeseed (canola) oil, sunflower oil or corn oil, or from
so-called "tall oil", a by-product of the manufacture of wood pulp. Most commonly occurring
phytosterols in human diet are β-Sitosterol, Campesterol and Stigmasterol. Therefore, regular
consumption of plant sterols and stanols in natural foods should not exceeding 3 g/day is
considered healthy to man and animals. Phytosterol absorption by various species ranging rabbit
0% rat 4%Human being 6%. Phytosterols are structurally very similar to cholesterol except that
they always contain some substitutions at the C24 position on the sterol side chain. Phytostanol
and phytosterol esters are chemically stable, fat type materials and having comparable chemical
and physical properties to edible fats and oils. Phytosterols are insoluble in water but are soluble
in non-polar solvents, such as hexane, iso-octane and 2-propanol. Phytosterols and phytostanols
are nonnutritive. Phytosterol has same basic functions in plants as cholesterol in animals. The
biological activities of Phytosterols in animals/humans includes (1) reduction of cholesterol
levels with decreased risk of coronary heart diseases. They were first reported to play a regulatory
role in serum cholesterol concentration in 1951. Level of Plasma phytosterol in mammalian tissues
are normally very low due to poor absorption from the intestine and faster excretion from the liver
compared to cholesterol. It can be metabolized in the liver of mammals into C21 bile acids instead
of the normal C24 bile acids.

3. (2) Anti-inflammatory activities, Attenuate the inflammatory activity of immune cells, including
macrophages and neutrophils. (3) Anticancer effect Protect against certain types of cancer such
as colon, breast and prostate. Mechanisms involves such as inhibition of carcinogen production,
stimulation of apoptosis. (4) Alteration in cell membrane properties because cholesterol is
replaced with phytosterols it has been found that it alters the physical properties of cell membranes,
potentially affect signal transduction or membrane-bound enzyme activity. (5) Alteration in
testosterone metabolism by inhibiting 5-alpha-reductase that converts testosterone to dihydro-
testosterone. Instead of having beneficial effects on human health they have some drawbacks
such as Nutrient interaction it makes the fat-soluble vitamin unavailable to human body such
vitamin A, D, E and K, Carotenoids are fat soluble phytochemicals it reduces the level of
carotenoids in blood plasma. The food or food products that are fortified with phytosterols are not
given to pregnant women because of their safety has not been yet studied. Phyto or plant stanol
esters and sterols may be added to many food products fat spreads, milk products, milk based fruit
drinks, fermented milk products, cheese products, yoghurt products, spice sauces, salad dressings,
juices and nectars. According to recent news and researches it has been added in dark chocolate
to produce a cholesterol cutting products that are capable of FDA (Food and Drug Administration)
claims. Phytosterols (Phyto bake) are also introduced into microwave pizza. Phytosterols enriched
peanut butter has also been introduced recently. Patients having asthma or other respiratory
diseases should be careful because many supplements are made from soy can trigger outbreaks.
Food authorities of different countries has specified the fortification level of phytosterols in food
products. Plant sterol, stanols and their esters has been given GRAS status in United States.
Scientific committee on food of the EU concluded that plant sterols and stanols added to various
food products are safe for human.