Grapefruit seed extract

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Grapefruit seed extract (GSE), also known as citrus seed extract, is a liquid extract derived from the seeds, pulp, and white membranes of grapefruit. [1] GSE is prepared by grinding the grapefruit seed and juiceless pulp, then mixing with glycerin. [1] Commercially available GSEs sold to consumers are made from the seed, pulp, and glycerin blended together. [1] GSE is sold as a dietary supplement and is used in cosmetics. [2]

Contents

Grapefruit history

The grapefruit is a subtropical citrus tree grown for its fruit which was originally named the "forbidden fruit" of Barbados. [3] The fruit was first documented in 1750 by Rev. Griffith Hughes when describing specimens from Barbados. [4] All parts of the fruit can be used. The fruit is mainly consumed for its tangy juice. [5] The peel can be processed into aromatherapy oils [6] and is also a source of dietary fiber. [7] The seed and pulp, as byproducts of the juice industry, are retrieved for GSE processing [8] or sold as cattle feed. [9]

Efficacy

Despite claims that GSE has antimicrobial effects, [10] there is no scientific evidence that GSE has such properties. [11] [8] Some evidence indicates that the suspected antimicrobial activity of GSE was due to the contamination or adulteration of commercial GSE preparations with synthetic antimicrobials or preservatives. [1] [2] [12] These chemicals were not present in grapefruit seed extracts prepared in the laboratory, and GSE preparations without the contaminants were found to possess no detectable antimicrobial effect. [1] Although citrus seed extract is sold in health food markets, [12] there is no good evidence for any antimicrobial activity. [1]

Phytochemicals

Analysis shows the phytochemicals of the seed extract and pulp are flavonoids, [13] [14] ascorbic acid (vitamin C), tocopherols, citric acid, limonoids, [15] [16] sterols, and minerals. [17]

Preparations

GSE is prepared by grinding the grapefruit seed and juiceless pulp, then mixing with glycerin. [1] Commercially available GSE is made from the seed, pulp, glycerin, and synthetic preservatives all blended together. [1]

Health claims and safety concerns

Although various health claims for using GSE are marketed in the dietary supplement industry, there is no scientific evidence from high-quality clinical research that it has any health effects, as of 2018. [8] [11] Phytochemicals in grapefruit seeds, particularly furanocoumarins and flavonoids, may cause adverse effects on health resulting from grapefruit–drug interactions that influence the intended therapeutic effects of some 85 prescription drugs. [11] [18] The main safety concern about GSE is inhibition of the liver enzyme, cytochrome P450, which controls liver metabolism of drugs; consequently, its inhibition by GSE unpredictably increases the blood concentrations of prescribed drugs. [18]

Related Research Articles

<i>Citrus</i> Genus of flowering plants in the Rutaceae family

Citrus is a genus of flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, lemons, grapefruits, pomelos, and limes. The genus Citrus is native to South Asia, East Asia, Southeast Asia, Melanesia, and Australia. Various citrus species have been used and domesticated by indigenous cultures in these areas since ancient times. From there its cultivation spread into Micronesia and Polynesia by the Austronesian expansion ; and to the Middle East and the Mediterranean via the incense trade route, and onwards to Europe and the Americas.

<span class="mw-page-title-main">Grapefruit</span> Citrus fruit

The grapefruit is a subtropical citrus tree known for its relatively large, sour to semi-sweet, somewhat bitter fruit. The interior flesh is segmented and varies in color from pale yellow to dark pink/red.

<span class="mw-page-title-main">Lime (fruit)</span> Citrus fruit

A lime is a citrus fruit, which is typically round, green in color, 3–6 centimetres (1.2–2.4 in) in diameter, and contains acidic juice vesicles.

<span class="mw-page-title-main">Flavonoid</span> Class of plant and fungus secondary metabolites

Flavonoids are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.

<span class="mw-page-title-main">Bitter orange</span> Hybrid citrus plant

Bitter orange, sour orange, Seville orange, bigarade orange, or marmalade orange is the citrus tree Citrus × aurantium and its fruit. It is native to Southeast Asia and has been spread by humans to many parts of the world. It is probably a cross between the pomelo, Citrus maxima, and the mandarin orange, Citrus reticulata.

<span class="mw-page-title-main">Pomelo</span> Citrus fruit from Southeast Asia

The pomelo, from the family Rutaceae, is the largest citrus fruit, and the principal ancestor of the grapefruit. It is a natural, non-hybrid, citrus fruit, native to Southeast Asia. Similar in taste to a sweet grapefruit, the pomelo is commonly consumed and used for festive occasions throughout Southeast Asia. As with the grapefruit, phytochemicals in the pomelo have the potential for drug interactions.

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Lovastatin, sold under the brand name Mevacor among others, is a statin medication, to treat high blood cholesterol and reduce the risk of cardiovascular disease. Its use is recommended together with lifestyle changes. It is taken by mouth.

<span class="mw-page-title-main">Juicing</span> Process of extracting juice from fruit or vegetables

Juicing is the process of extracting juice from plant tissues such as fruit or vegetables.

<i>Citrus depressa</i> Species of fruit and plant

Citrus depressa (Citrus × depressa, formerly C. pectinifera, Okinawan: シークヮーサー/シークァーサー, romanized: shiikwaasa, Japanese: ヒラミレモン, romanized: hirami remon or シークワーサー, shiikuwāsā, in English sometimes called shiikuwasha, shequasar, Taiwan tangerine, Okinawa lime, flat lemon, hirami lemon, or thin-skinned flat lemon, is a small citrus fruit often harvested and used when green, rich in flavonoids and native to East Asia.

<span class="mw-page-title-main">Grapefruit juice</span> Fruit juice from grapefruits

Grapefruit juice is the juice from grapefruits. It is rich in vitamin C and ranges from sweet-tart to very sour. Variations include white grapefruit, pink grapefruit and ruby red grapefruit juice.

<span class="mw-page-title-main">Naringenin</span> Chemical compound

Naringenin is a flavorless, colorless flavanone, a type of flavonoid. It is the predominant flavanone in grapefruit, and is found in a variety of fruits and herbs.

<span class="mw-page-title-main">Naringin</span> Chemical compound

Naringin is a flavanone-7-O-glycoside between the flavanone naringenin and the disaccharide neohesperidose. The flavonoid naringin occurs naturally in citrus fruits, especially in grapefruit, where naringin is responsible for the fruit's bitter taste. In commercial grapefruit juice production, the enzyme naringinase can be used to remove the bitterness created by naringin. In humans naringin is metabolized to the aglycone naringenin by naringinase present in the gut.

<span class="mw-page-title-main">Hesperidin</span> Chemical compound

Hesperidin is a flavanone glycoside found in citrus fruits. Its aglycone form is called hesperetin. Its name is derived from the word "hesperidium", for fruit produced by citrus trees.

<span class="mw-page-title-main">Grapefruit–drug interactions</span> Drug interactions with grapefruit juice

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<span class="mw-page-title-main">Sea buckthorn oil</span> Vegetable oil

Sea buckthorn oil is a red-orange oil derived from sea buckthorn plants. The most commonly used species for this purpose is Hippophae rhamnoides. Species belonging to this genus accumulate lipids in the mesocarp, so the oil can be extracted from either the seeds or the pulp.

<span class="mw-page-title-main">Flavonols</span> Class of plant and fungus secondary metabolites

Flavonols are a class of flavonoids that have the 3-hydroxyflavone backbone. Their diversity stems from the different positions of the phenolic –OH groups. They are distinct from flavanols such as catechin, another class of flavonoids.

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The phenolic content in wine refers to the phenolic compounds—natural phenol and polyphenols—in wine, which include a large group of several hundred chemical compounds that affect the taste, color and mouthfeel of wine. These compounds include phenolic acids, stilbenoids, flavonols, dihydroflavonols, anthocyanins, flavanol monomers (catechins) and flavanol polymers (proanthocyanidins). This large group of natural phenols can be broadly separated into two categories, flavonoids and non-flavonoids. Flavonoids include the anthocyanins and tannins which contribute to the color and mouthfeel of the wine. The non-flavonoids include the stilbenoids such as resveratrol and phenolic acids such as benzoic, caffeic and cinnamic acids.

<span class="mw-page-title-main">Juice vesicles</span> Component of citrus pulp

The juice vesicles, also known as citrus kernels, of a citrus fruit are the membranous content of the fruit's endocarp. All fruits from the Citranae subtribe, subfamily Aurantioideae, and family Rutaceae have juice vesicles. The vesicles contain the juice of the fruit and appear shiny and sacklike. Vesicles come in two shapes: the superior and inferior, and these are distinct. Citrus fruit with more vesicles generally weighs more than those with fewer vesicles. Fruits with many segments, such as the grapefruit or pomelo, have more vesicles per segment than fruits with fewer segments, such as the kumquat and mandarin. Each vesicle in a segment in citrus fruits has approximately the same shape, size, and weight. About 5% of the weight of an average orange is made up of the membranes of the juice vesicles.

<span class="mw-page-title-main">Lemon</span> Yellow citrus fruit

The lemon is a species of small evergreen tree in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar, or China.

<span class="mw-page-title-main">6',7'-Dihydroxybergamottin</span> Chemical compound

6',7'-Dihydroxybergamottin is a natural furanocoumarin found in pomelos, grapefruits, and sour oranges, in both the peel and the pulp. Along with the chemically related compound bergamottin, it is believed to be responsible for a number of grapefruit–drug interactions, in which the consumption of citrus containing one or both of these compounds affects the metabolism of a variety of pharmaceutical drugs.

References

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