β-Sitosterol is one of several phytosterol

Phytosterol

Phytosterols, which encompass plant sterols and stanols, are steroid compounds similar to cholesterol which occur in plants and vary only in carbon side chains and/or presence or absence of a double bond. Stanols are saturated sterols, having no double bonds in the sterol ring structure. More than...

s (plant sterols) with chemical structure

Chemical structure

A chemical structure includes molecular geometry, electronic structure and crystal structure of molecules. Molecular geometry refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together. Molecular geometry can range from the very simple, such as...

s similar to that of cholesterol

Cholesterol

Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...

. Sitosterols are white, waxy powders with a characteristic odor. They are hydrophobic and soluble in alcohols.
It is widely distributed in the plant kingdom and found in Nigella sativa

Nigella sativa

Nigella sativa is an annual flowering plant, native to south and southwest Asia. It grows to tall, with finely divided, linear leaves. The flowers are delicate, and usually coloured pale blue and white, with five to ten petals. The fruit is a large and inflated capsule composed of three to seven...

, pecan

Pecan

The pecan , Carya illinoinensis, is a species of hickory, native to south-central North America, in Mexico from Coahuila south to Jalisco and Veracruz, in the United States from southern Iowa, Illinois, Missouri, and Indiana east to western Kentucky, southwestern Ohio, North Carolina, South...

s, Serenoa repens

Saw Palmetto

Serenoa repens, commonly known as saw palmetto, is the sole species currently classified in the genus Serenoa. It has been known by a number of synonyms, including Sabal serrulatum, under which name it still often appears in alternative medicine. It is a small palm, normally reaching a height of...

(saw palmetto), avocados, Cucurbita pepo

Cucurbita pepo

The species Cucurbita pepo is a cultivated plant of the genus Cucurbita. It includes varieties of squash, gourd, and pumpkin.*Acorn squash*Delicata squash*Dodi marrow, grown in South Asia*Gem squash*Heart of gold squash*Pattypan squash...

(pumpkin seed), Pygeum africanum, cashew

Cashew

The cashew is a tree in the family Anacardiaceae. Its English name derives from the Portuguese name for the fruit of the cashew tree, caju, which in turn derives from the indigenous Tupi name, acajú. It is now widely grown in tropical climates for its cashew nuts and cashew apples.-Etymology:The...

 fruit, rice bran, wheat germ, corn oil

Corn oil

Corn oil is oil extracted from the germ of corn . Its main use is in cooking, where its high smoke point makes refined corn oil a valuable frying oil. It is also a key ingredient in some margarines. Corn oil is generally less expensive than most other types of vegetable oils. One bushel of corn...

s, soybean

Soybean

The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...

s, sea-buckthorn

Sea-buckthorn

The sea-buckthorns are deciduous shrubs in the genus Hippophae, family Elaeagnaceae. The name sea-buckthorn is hyphenated here to avoid confusion with the buckthorns...

, wolfberries

Wolfberry

Wolfberry, commercially called goji berry, is the common name for the fruit of two very closely related species: Lycium barbarum and L. chinense , two species of boxthorn in the family Solanaceae...

, and Wrightia tinctoria

Wrightia tinctoria

Wrightia tinctoria, Pala indigo plant or dyers’s oleander, is a flowering plant species in the genus Wrightia found in India.The plant contains wrightial, a triterpenoid chemical, along with cycloartenone, cycloeucalenol, β-amyrin, and β-sitosterol isolated from the MeOH extract of the immature...

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Alone and in combination with similar phytosterols, β-sitosterol reduces blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

 levels of cholesterol

Cholesterol

Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...

, and is sometimes used in treating hypercholesterolemia

Hypercholesterolemia

Hypercholesterolemia is the presence of high levels of cholesterol in the blood. It is not a disease but a metabolic derangement that can be caused by many diseases, notably cardiovascular disease...

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