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{{Short description|Extract derived from grapefruit seeds}}
{{distinguish|grape seed extract}} {{distinguish|grape seed extract}}
'''Grapefruit seed extract''' (GSE), also known as '''citrus seed extract''', is a liquid ] derived from the ]s, ], and ] of ].<ref name=Pharmazie/> GSE is prepared by grinding the grapefruit seed and juiceless pulp, then mixing with ].<ref name=Pharmazie/> Commercially available GSEs sold to consumers are made from the seed, pulp, and glycerin blended together.<ref name=Pharmazie/> GSE is sold as a ] and is used in ].<ref name=Preservatives/> '''Grapefruit seed extract''' (GSE), also known as '''citrus seed extract''', is a liquid ] derived from the ]s, ], and ] of ].<ref name=Pharmazie/> GSE is prepared by grinding the grapefruit seed and juiceless pulp, then mixing with ].<ref name=Pharmazie/> Commercially available GSEs sold to consumers are made from the seed, pulp, and glycerin blended together.<ref name=Pharmazie/> GSE is sold as a ] and is used in ].<ref name=Preservatives/>
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== Grapefruit history == == Grapefruit history ==


The grapefruit is a subtropical ] ] grown for its ] which was originally named the "]" of ].<ref name="Forbidden_Fruit">{{cite book |author1=Dowling, Curtis F. |author2=Morton, Julia Frances |title=Fruits of warm climates |publisher=J.F. Morton |location=Miami, Fla |year=1987 |pages=152–8 |isbn=978-0-9610184-1-2|url=http://www.hort.purdue.edu/newcrop/morton/grapefruit.html}}</ref> The fruit was first documented in 1750 by Rev. ] when describing specimens from Barbados.<ref name="Q_A:Grapefruit">Michael Quinion. . 2009.</ref> All parts of the fruit can be used. The fruit is mainly consumed for its tangy ].<ref name="Citrus_Juice">{{cite journal |vauthors=Fellers PJ, Nikdel S, Lee HS |title=Nutrient content and nutrition labeling of several processed Florida citrus juice products |journal=J Am Diet Assoc |volume=90 |issue=8 |pages=1079–84 |date=August 1990 |pmid=2380455 }}</ref> The peel can be processed into ] ]s<ref name=Valerie>{{cite book |author=Worwood, Valerie Ann |title=The complete book of essential oils and aromatherapy |publisher=New World Library |location=Novato, Calif |year=1991 |isbn=978-0-931432-82-8 |url-access=registration |url=https://archive.org/details/completebookofes00worw }}</ref> and is also a source of ].<ref name="Pectin_Benefits">{{cite journal |vauthors=Cerda JJ, Robbins FL, Burgin CW, Baumgartner TG, Rice RW |title=The effects of grapefruit pectin on patients at risk for coronary heart disease without altering diet or lifestyle |journal=Clin Cardiol |volume=11 |issue=9 |pages=589–94 |date=September 1988 |pmid=3229016 |doi=10.1002/clc.4960110902 |s2cid=45520617 }}</ref> The seed and pulp, as ]s of the juice industry, are retrieved for GSE processing<ref name="gravura">{{cite web|author1=Scott Gravura|date=10 March 2016|title=Not natural, not safe: Grapefruit seed extract|url=https://sciencebasedmedicine.org/not-natural-not-safe-grapefruit-seed-extract/|accessdate=17 November 2018|publisher=Science-based Medicine}}</ref> or sold as ].<ref name="Cattle_Feed">{{cite journal |vauthors=Arthington JD, Kunkle WE, Martin AM |title=Citrus pulp for cattle |journal=Vet. Clin. North Am. Food Anim. Pract. |volume=18 |issue=2 |pages=317–26, vii |date=July 2002 |pmid=12235663 |doi=10.1016/S0749-0720(02)00023-3 }}</ref> The grapefruit is a subtropical ] ] grown for its ] which was originally named the "]" of ].<ref name="Forbidden_Fruit">{{cite book |author1=Dowling, Curtis F. |author2=Morton, Julia Frances |title=Fruits of warm climates |publisher=J.F. Morton |location=Miami, Fla |year=1987 |pages=152–8 |isbn=978-0-9610184-1-2|url=http://www.hort.purdue.edu/newcrop/morton/grapefruit.html}}</ref> The fruit was first documented in 1750 by Rev. ] when describing specimens from Barbados.<ref name="Q_A:Grapefruit">Michael Quinion. . 2009.</ref> All parts of the fruit can be used. The fruit is mainly consumed for its tangy ].<ref name="Citrus_Juice">{{cite journal |vauthors=Fellers PJ, Nikdel S, Lee HS |title=Nutrient content and nutrition labeling of several processed Florida citrus juice products |journal=J Am Diet Assoc |volume=90 |issue=8 |pages=1079–84 |date=August 1990 |doi=10.1016/S0002-8223(21)01704-1 |pmid=2380455 |s2cid=25833812 }}</ref> The peel can be processed into ] ]s<ref name=Valerie>{{cite book |author=Worwood, Valerie Ann |title=The complete book of essential oils and aromatherapy |publisher=New World Library |location=Novato, Calif |year=1991 |isbn=978-0-931432-82-8 |url-access=registration |url=https://archive.org/details/completebookofes00worw }}</ref> and is also a source of ].<ref name="Pectin_Benefits">{{cite journal |vauthors=Cerda JJ, Robbins FL, Burgin CW, Baumgartner TG, Rice RW |title=The effects of grapefruit pectin on patients at risk for coronary heart disease without altering diet or lifestyle |journal=Clin Cardiol |volume=11 |issue=9 |pages=589–94 |date=September 1988 |pmid=3229016 |doi=10.1002/clc.4960110902 |s2cid=45520617 |doi-access=free }}</ref> The seed and pulp, as ]s of the juice industry, are retrieved for GSE processing<ref name="gravura">{{cite web|author1=Scott Gravura|date=10 March 2016|title=Not natural, not safe: Grapefruit seed extract|url=https://sciencebasedmedicine.org/not-natural-not-safe-grapefruit-seed-extract/|accessdate=17 November 2018|publisher=Science-based Medicine}}</ref> or sold as ].<ref name="Cattle_Feed">{{cite journal |vauthors=Arthington JD, Kunkle WE, Martin AM |title=Citrus pulp for cattle |journal=Vet. Clin. North Am. Food Anim. Pract. |volume=18 |issue=2 |pages=317–26, vii |date=July 2002 |pmid=12235663 |doi=10.1016/S0749-0720(02)00023-3 }}</ref>


== Efficacy == == Efficacy ==


Despite ] that GSE has ] effects,<ref name=EthanolGSE>{{cite journal |author=Cvetnić Z, Vladimir-Knezević S |title=Antimicrobial activity of grapefruit seed and pulp ethanolic extract |journal=Acta Pharm |volume=54 |issue=3 |pages=243–50 |date=September 2004 |pmid=15610620 }}</ref> there is no scientific evidence that GSE has such properties.<ref name="drugs">{{cite web|date=15 January 2018|title=Grapefruit|url=https://www.drugs.com/npp/grapefruit.html|accessdate=17 November 2018|publisher=Drugs.com}}</ref><ref name=gravura/> 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 ].<ref name=Pharmazie>{{cite journal |vauthors=von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD |title=Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained |journal=Pharmazie |volume=54 |issue=6 |pages=452–6 |date=June 1999 |pmid=10399191 }}</ref><ref name=Preservatives>{{cite journal |vauthors=Ganzera M, Aberham A, Stuppner H |title=Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract |journal=J. Agric. Food Chem. |volume=54 |issue=11 |pages=3768–72 |date=May 2006 |pmid=16719494 |doi=10.1021/jf060543d }}</ref><ref name=Adulteration>{{cite journal |vauthors=Takeoka GR, Dao LT, Wong RY, Harden LA |title=Identification of benzalkonium chloride in commercial grapefruit seed extracts |journal=J. Agric. Food Chem. |volume=53 |issue=19 |pages=7630–6 |date=September 2005 |pmid=16159196 |doi=10.1021/jf0514064 }}</ref> These chemicals were not present in grapefruit seed extracts prepared in the ], and GSE preparations without the contaminants were found to possess no detectable antimicrobial effect.<ref name=Pharmazie/> Although citrus seed extract is sold in ],<ref name=Adulteration/> there is no good evidence for any antimicrobial activity.<ref name=Pharmazie/> Despite ] that GSE has ] effects,<ref name=EthanolGSE>{{cite journal |author=Cvetnić Z, Vladimir-Knezević S |title=Antimicrobial activity of grapefruit seed and pulp ethanolic extract |journal=Acta Pharm |volume=54 |issue=3 |pages=243–50 |date=September 2004 |pmid=15610620 }}</ref> there is no scientific evidence that GSE has such properties.<ref name="drugs">{{cite web|date=15 January 2018|title=Grapefruit|url=https://www.drugs.com/npp/grapefruit.html|accessdate=17 November 2018|publisher=Drugs.com}}</ref><ref name=gravura/> 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 ].<ref name=Pharmazie>{{cite journal |vauthors=von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD |title=Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained |journal=Pharmazie |volume=54 |issue=6 |pages=452–6 |date=June 1999 |pmid=10399191 }}</ref><ref name=Preservatives>{{cite journal |vauthors=Ganzera M, Aberham A, Stuppner H |title=Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract |journal=J. Agric. Food Chem. |volume=54 |issue=11 |pages=3768–72 |date=May 2006 |pmid=16719494 |doi=10.1021/jf060543d }}</ref><ref name=Adulteration>{{cite journal |vauthors=Takeoka GR, Dao LT, Wong RY, Harden LA |title=Identification of benzalkonium chloride in commercial grapefruit seed extracts |journal=J. Agric. Food Chem. |volume=53 |issue=19 |pages=7630–6 |date=September 2005 |pmid=16159196 |doi=10.1021/jf0514064 }}</ref> These chemicals were not present in grapefruit seed extracts prepared in the ], and GSE preparations without the contaminants were found to possess no detectable antimicrobial effect.<ref name=Pharmazie/> Although citrus seed extract is sold in ],<ref name=Adulteration/> there is no good evidence for any antimicrobial activity.<ref name=Pharmazie/>

A study that examined possible ] properties of GSE found that it had no efficacy as a ] for ] and ].<ref name="Virucidal_Efficacy">{{cite journal |vauthors=Eleraky NZ, Potgieter LN, Kennedy MA |title=Virucidal efficacy of four new disinfectants |journal=J Am Anim Hosp Assoc |volume=38 |issue=3 |pages=231–4 |year=2002 |pmid=12022408 |doi=10.5326/0380231 }}</ref>


== Phytochemicals == == Phytochemicals ==


Analysis shows the ]s of the seed extract and pulp are ],<ref name=Drewnowski>{{cite journal |vauthors=Drewnowski A, Gomez-Carneors C |title=Bitter taste, phytonutrients, and consumer: a review |journal=Am. J. Clin. Nutr. |volume=72 |pages=1424–35 |year=2000 |pmid=11101467 |issue=6 |doi=10.1093/ajcn/72.6.1424 |doi-access=free }}</ref><ref name=Tirillini>{{cite journal |author=Tirillini B |title= Grapefruit: the last decade acquisitions |journal=Fitoterapia |volume=71 |pages=29–37 |year=2000 |doi=10.1016/S0367-326X(00)00176-3 |pmid=10930710}}</ref> ] (]), ]s, ], ]s,<ref name="Glucosides_Of_Acidic_Limonoids">{{cite journal |vauthors=Bennett RD, Hasegava S, Herman Z |title=Glucosides of acidic limonoids in citrus |journal=Phytochemistry |volume=28 |pages=2777–81 |year=1989 |doi=10.1016/S0031-9422(00)98087-7 |issue=10 |url=https://zenodo.org/record/1259689 }}</ref><ref name="Limonoide_Glucosides">{{cite journal |author=Ohta H, Fong CH, Berhow M, Hesegawa |title=Thin-layer and high-performance liquid chromatographic analyses of limonoids and limonoid glucosides in citrus seeds |journal=J. Chromatogr. |volume=639 |pages=295–302 |year=1993 |doi=10.1016/0021-9673(93)80266-B |issue=2 |url=https://zenodo.org/record/1253912 }}</ref> ], and ].<ref name=Tushiswilli>{{cite journal |vauthors=Tushiswili LS, Durmishidze SV, Sulaberidze KV |title=Sterols of grapefruit, orange, mandarin pulps (''Citrus paradisi, Citrus sinensis, Citrus unshiu'') |journal=Chemistry of Natural Compounds |volume=18 |pages=445–7 |year=1983 |doi=10.1007/BF00579640 |s2cid=4814220 }}</ref> Analysis shows the ]s of the seed extract and pulp are ],<ref name=Drewnowski>{{cite journal |vauthors=Drewnowski A, Gomez-Carneors C |title=Bitter taste, phytonutrients, and consumer: a review |journal=Am. J. Clin. Nutr. |volume=72 |pages=1424–35 |year=2000 |pmid=11101467 |issue=6 |doi=10.1093/ajcn/72.6.1424 |doi-access=free }}</ref><ref name=Tirillini>{{cite journal |author=Tirillini B |title= Grapefruit: the last decade acquisitions |journal=Fitoterapia |volume=71 |pages=29–37 |year=2000 |doi=10.1016/S0367-326X(00)00176-3 |pmid=10930710}}</ref> ] (]), ]s, ], ]s,<ref name="Glucosides_Of_Acidic_Limonoids">{{cite journal |vauthors=Bennett RD, Hasegava S, Herman Z |title=Glucosides of acidic limonoids in citrus |journal=Phytochemistry |volume=28 |pages=2777–81 |year=1989 |doi=10.1016/S0031-9422(00)98087-7 |issue=10 |bibcode=1989PChem..28.2777B |url=https://zenodo.org/record/1259689 }}</ref><ref name="Limonoide_Glucosides">{{cite journal |author=Ohta H, Fong CH, Berhow M, Hesegawa |title=Thin-layer and high-performance liquid chromatographic analyses of limonoids and limonoid glucosides in citrus seeds |journal=J. Chromatogr. |volume=639 |pages=295–302 |year=1993 |doi=10.1016/0021-9673(93)80266-B |issue=2 |url=https://zenodo.org/record/1253912 }}</ref> ], and ].<ref name=Tushiswilli>{{cite journal |vauthors=Tushiswili LS, Durmishidze SV, Sulaberidze KV |title=Sterols of grapefruit, orange, mandarin pulps (''Citrus paradisi, Citrus sinensis, Citrus unshiu'') |journal=Chemistry of Natural Compounds |volume=18 |pages=445–7 |year=1983 |doi=10.1007/BF00579640 |s2cid=4814220 }}</ref>


== Preparations == == Preparations ==
Line 22: Line 21:
==Health claims and safety concerns== ==Health claims and safety concerns==


Although various health claims for using GSE are marketed in the ] industry, there is no ] from high-quality ] that it has any health effects, as of 2018.<ref name=gravura/><ref name=drugs/> Phytochemicals in grapefruit seeds, particularly]s and flavonoids, may cause ] resulting from ] that influence the intended therapeutic effects of some 85 ]s.<ref name=drugs/><ref name="bailey">{{cite journal |last1=Bailey |first1=D. G. |last2=Dresser |first2=G. |last3=Arnold |first3=J. M. O. |title=Grapefruit-medication interactions: Forbidden fruit or avoidable consequences? |journal=Canadian Medical Association Journal |volume=185 |issue=4 |year=2012 |pages=309–316 |doi=10.1503/cmaj.120951 |pmid=23184849 |pmc=3589309}}</ref> The main safety concern about GSE is inhibition of the ] ], ], which controls liver ]; consequently, its inhibition by GSE unpredictably increases the blood concentrations of prescribed drugs.<ref name=bailey/> Although various health claims for using GSE are marketed in the ] industry, there is no ] from high-quality ] that it has any health effects, as of 2018.<ref name=gravura/><ref name=drugs/> Phytochemicals in grapefruit seeds, particularly ]s and flavonoids, may cause ] resulting from ] that influence the intended therapeutic effects of some 85 ]s.<ref name=drugs/><ref name="bailey">{{cite journal |last1=Bailey |first1=D. G. |last2=Dresser |first2=G. |last3=Arnold |first3=J. M. O. |title=Grapefruit-medication interactions: Forbidden fruit or avoidable consequences? |journal=Canadian Medical Association Journal |volume=185 |issue=4 |year=2012 |pages=309–316 |doi=10.1503/cmaj.120951 |pmid=23184849 |pmc=3589309}}</ref> The main safety concern about GSE is inhibition of the ] ], ], which controls liver ]; consequently, its inhibition by GSE unpredictably increases the blood concentrations of prescribed drugs.<ref name=bailey/>


== References == == References ==

Latest revision as of 18:53, 12 July 2024

Extract derived from grapefruit seeds Not to be confused with grape seed extract.

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

Grapefruit history

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

Efficacy

Despite claims that GSE has antimicrobial effects, there is no scientific evidence that GSE has such properties. 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. 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. Although citrus seed extract is sold in health food markets, there is no good evidence for any antimicrobial activity.

Phytochemicals

Analysis shows the phytochemicals of the seed extract and pulp are flavonoids, ascorbic acid (vitamin C), tocopherols, citric acid, limonoids, sterols, and minerals.

Preparations

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

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. 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. 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.

References

  1. ^ von Woedtke T, Schlüter B, Pflegel P, Lindequist U, Jülich WD (June 1999). "Aspects of the antimicrobial efficacy of grapefruit seed extract and its relation to preservative substances contained". Pharmazie. 54 (6): 452–6. PMID 10399191.
  2. ^ Ganzera M, Aberham A, Stuppner H (May 2006). "Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract". J. Agric. Food Chem. 54 (11): 3768–72. doi:10.1021/jf060543d. PMID 16719494.
  3. Dowling, Curtis F.; Morton, Julia Frances (1987). Fruits of warm climates. Miami, Fla: J.F. Morton. pp. 152–8. ISBN 978-0-9610184-1-2.
  4. Michael Quinion. World Wide Words: Questions & Answers; Grapefruit. 2009.
  5. Fellers PJ, Nikdel S, Lee HS (August 1990). "Nutrient content and nutrition labeling of several processed Florida citrus juice products". J Am Diet Assoc. 90 (8): 1079–84. doi:10.1016/S0002-8223(21)01704-1. PMID 2380455. S2CID 25833812.
  6. Worwood, Valerie Ann (1991). The complete book of essential oils and aromatherapy. Novato, Calif: New World Library. ISBN 978-0-931432-82-8.
  7. Cerda JJ, Robbins FL, Burgin CW, Baumgartner TG, Rice RW (September 1988). "The effects of grapefruit pectin on patients at risk for coronary heart disease without altering diet or lifestyle". Clin Cardiol. 11 (9): 589–94. doi:10.1002/clc.4960110902. PMID 3229016. S2CID 45520617.
  8. ^ Scott Gravura (10 March 2016). "Not natural, not safe: Grapefruit seed extract". Science-based Medicine. Retrieved 17 November 2018.
  9. Arthington JD, Kunkle WE, Martin AM (July 2002). "Citrus pulp for cattle". Vet. Clin. North Am. Food Anim. Pract. 18 (2): 317–26, vii. doi:10.1016/S0749-0720(02)00023-3. PMID 12235663.
  10. Cvetnić Z, Vladimir-Knezević S (September 2004). "Antimicrobial activity of grapefruit seed and pulp ethanolic extract". Acta Pharm. 54 (3): 243–50. PMID 15610620.
  11. ^ "Grapefruit". Drugs.com. 15 January 2018. Retrieved 17 November 2018.
  12. ^ Takeoka GR, Dao LT, Wong RY, Harden LA (September 2005). "Identification of benzalkonium chloride in commercial grapefruit seed extracts". J. Agric. Food Chem. 53 (19): 7630–6. doi:10.1021/jf0514064. PMID 16159196.
  13. Drewnowski A, Gomez-Carneors C (2000). "Bitter taste, phytonutrients, and consumer: a review". Am. J. Clin. Nutr. 72 (6): 1424–35. doi:10.1093/ajcn/72.6.1424. PMID 11101467.
  14. Tirillini B (2000). "Grapefruit: the last decade acquisitions". Fitoterapia. 71: 29–37. doi:10.1016/S0367-326X(00)00176-3. PMID 10930710.
  15. Bennett RD, Hasegava S, Herman Z (1989). "Glucosides of acidic limonoids in citrus". Phytochemistry. 28 (10): 2777–81. Bibcode:1989PChem..28.2777B. doi:10.1016/S0031-9422(00)98087-7.
  16. Ohta H, Fong CH, Berhow M, Hesegawa (1993). "Thin-layer and high-performance liquid chromatographic analyses of limonoids and limonoid glucosides in citrus seeds". J. Chromatogr. 639 (2): 295–302. doi:10.1016/0021-9673(93)80266-B.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  17. Tushiswili LS, Durmishidze SV, Sulaberidze KV (1983). "Sterols of grapefruit, orange, mandarin pulps (Citrus paradisi, Citrus sinensis, Citrus unshiu)". Chemistry of Natural Compounds. 18: 445–7. doi:10.1007/BF00579640. S2CID 4814220.
  18. ^ Bailey, D. G.; Dresser, G.; Arnold, J. M. O. (2012). "Grapefruit-medication interactions: Forbidden fruit or avoidable consequences?". Canadian Medical Association Journal. 185 (4): 309–316. doi:10.1503/cmaj.120951. PMC 3589309. PMID 23184849.
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