Castor oil

Castor oil is a vegetable oil obtained from the castor bean (technically "castor seed" as the castor plant, "Ricinus communis", is not a member of the bean family). Castor oil (CAS number 8001-79-4) is a colorless to very pale yellow liquid with mild or no odor or taste. Its boiling point is convert|313|C|F and its density is 961 "kg·m^-3". [Aldrich Handbook of Fine Chemicals and Laboratory Equipment, Sigma-Aldrich, 2003.] It is a triglyceride in which approximately ninety percent of fatty acid chains are ricinoleic acid. Oleic and linoleic acids are the other significant components. [cite web
url=http://www.nnfcc.co.uk/crops/info/castor.pdf
title=Castor
publisher=The National Non-Food Crops Centre
accessdate=2007-07-06]

The structure of the major component of castor oil is shown below:

Background

Ricinoleic acid, a monounsaturated, 18-carbon fatty acid, is unusual in that it has a hydroxyl functional group on the twelfth carbon. This functional group causes ricinoleic acid (and castor oil) to be unusually polar, and also allows chemical derivatization that is not practical with most other seed oils. It is the hydroxyl group which makes castor oil and ricinoleic acid valuable as chemical feedstocks. Compared to other seed oils which lack the hydroxyl group, castor oil demands a higher price. As an example, in July 2007 Indian castor oil sold for about US$0.90 per kilogram (US$0.41 per pound) [cite web|url=http://www.castorworld.com/market.asp|title= July 2007 commodity price for Indian castor oil|accessdate=2008-08-10] while US soybean, sunflower and canola oil sold for about US$0.30 per kilogram (US$0.14 per pound) [cite web|url=http://www.fas.usda.gov/oilseeds/circular/2007/July/oilseedsfull0707.pdf|title=Seed oil prices from US Dept. of Agriculture, see page 31|accessdate=2008-08-10]

Castor oil and its derivatives have applications in the manufacturing of soaps, lubricants, hydraulic and brake fluids, paints, dyes, coatings, inks, cold resistant plastics, waxes and polishes, nylon, pharmaceuticals and perfumes.

Sulfonated castor oil, also called Sulfonated (sulfated) castor oil, or Turkey Red Oil, is the only oil that completely disperses in water. It is made by adding sulfuric acid to pure castor oil [ [http://www.porwal.net/turkeyredoil.htm Turkey Red Oil - A defoaming & wetting agent, manure, lubricant ] ] . This allows easy use for making bath oil products. It was the first synthetic detergent after ordinary soap. It is used in formulating lubricants, softeners, and dyeing assistants [CastorOil.in – Home of Castor Oil Online [http://www.castoroil.in/reference/glossary/turkey_red_oil.html] ] .

The castor seed contains ricin, a toxic protein removed by cold pressing and filtering. [cite web | url=http://www.icoa.org/toxic.htm | title=Castor Oil is non-toxic | publisher=ICOA | accessdate=2006-12-28] However, harvesting castor beans is not without risk, [cite journal
last =Auld
first =Dick L.
authorlink =
coauthors = Pinkerton,Scott D.; Rolfe, Rial; Ghetie, Victor and Lauterbach, Brenda F.
title = Selection of Castor for Divergent Concentrations of Ricin and Ricinus communis Agglutinin and references therein
journal =Crop Science
volume =39
issue =MARCH–APRIL
pages =353–357
date= 1999
url =http://crop.scijournals.org/cgi/reprint/39/2/353.pdf
doi =
id =
accessdate =2007-07-31 ] Allergenic compounds found on the plant surface can cause permanent nerve damage, making the harvest of castor beans a human health risk. India, Brazil and China are the major crop producers and the workers suffer harmful side effects from working with these plants. [cite web|url=http://www.linnaeus.net/problem_with_castor.htm|title=Hazards of harvesting castor plants|accessdate=2007-07-31] These health issues, in addition to concerns about the toxic byproduct (ricin) from castor oil production, have encouraged the quest for alternative, domestic sources for hydroxy fatty acids. [cite web | last=Dierig | first=David A. | title=Lesquerella | work=New Crop FactSHEET | publisher=Center for New Crops & Plant Products, at Purdue University | date=1995 | url=http://www.hort.purdue.edu/newcrop/cropfactsheets/Lesquerella.html | accessdate=2007-08-01 ] [cite web | last=Dierig | first=David A. | title=Lesquerella | work= | publisher=The National Non-Food Crops Centre | date=2002 | url=http://www.nnfcc.co.uk/crops/info/lesquerella.pdf | format= | doi= | accessdate=2007-08-01] Alternatively, some researchers are trying to genetically modify the castor plant to prevent the synthesis of ricin. [cite journal | last=Wood | first=M. | title=High-Tech Castor Plants May Open Door to Domestic Production | journal=Agricultural Research Magazine | volume=49 | issue=1 | pages= | date=2001 | url=http://www.ars.usda.gov/is/AR/archive/jan01/plant0101.htm | doi= | id= | accessdate=2007-08-02]

Castor oil fatty acids

Uses

Castor oil in food

In the food industry, castor oil (food grade) is used in food additives, [ [http://www.kristinasoil.com/fyi.html#food Castor Oil Facts ] ] flavorings, candy (i.e., chocolate), [cite web | title=Overview of the preparation, use and biological studies on polyglycerol polyricinoleate (PGPR) | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=9737417&query_hl=1&itool=pubmed_docsum | format=| publisher=PubMed | accessdate=2007-01-26] as a mold inhibitor, and in packaging. Polyoxyethylated castor oil (eg. Cremophor EL) [cite web |title=BASF Technical data sheet on Cremophor EL®|url=http://www.basf-korea.co.kr/.../04_finechemicals/document/cosmetic/tech/surfactants/down.asp?file=cremophorel.pdf |accessdate=2007-08-01] is also used in the foodstuff industries. [cite web | title=Cremophor EL® stimulates mitotic recombination in uvsH//uvsH diploid strain of Aspergillus nidulans. | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=15048194 | format=| publisher=PubMed | accessdate=2007-01-26]

Medicinal use of castor oil

The United States Food and Drug Administration (FDA) has categorized castor oil as "generally recognized as safe and effective" (GRASE) for over-the-counter use as a laxative, with its major site of action the small intestine. [cite web | url=http://www.fda.gov/cder/Offices/OTC/Ingredient_List_A-C.pdf | title=Ingredient List A-C | publisher=FDA (see page 52 of this link)| accessdate=2006-12-28] However, it is not a preferred treatment for constipation. [ Castor Oil. DRUGDEX® System. n.d. Thomson Micromedex. Retrieved February 19, 2007 [http://www.thomsonhc.com] ] Undecylenic acid, a castor oil derivative, is also FDA-approved for over-the-counter use on skin disorders or skin problems. [cite web | url=http://www.fda.gov/cder/Offices/OTC/Ingredient_List_P-Z.pdf | title=Ingredient List P-Z | publisher=FDA (see page 65 of this link)| accessdate=2006-12-28]
Castor oil penetrates deep into the skin thanks to its Molecular Weight. At 298 u., research on transdermal absorption indicates castor oil will penetrate the stratum corneum since it is below the 500 u. required to do so [http://www.evcforum.net/cgi-bin/dm.cgi?action=msg&f=14&t=1700&m=31] .

Ricinoleic acid is the main component of castor oil and it exerts anti-inflammatory effects. [cite web | title=Effect of ricinoleic acid in acute and subchronic experimental models of inflammation | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=search&term=11200362 | format=| publisher=PubMed | accessdate=2007-01-06]

One study has found that castor oil decreased pain more than ultrasound gel or Vaseline during extracorporeal shock wave application. [cite web | title=Castor oil decreases pain during extracorporeal shockwave application | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=10613232 | format=| publisher=PubMed | accessdate=2007-01-15]

Therapeutically, modern drugs are rarely given in a pure chemical state, so most active ingredients are combined with excipients or additives. Castor oil, or a castor oil derivative such as Cremophor EL (polyethoxylated castor oil, a nonionic surfactant), is added to many modern drugs, including:
*Miconazole, an anti-fungal agent; [cite web | title=Reversible Thrombocytosis and Anemia Due to Miconazole Therapy | url=http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=429768&blobtype=pdf | format=pdf| publisher=PubMed | accessdate=2007-01-06 See page 1, Methods and Materials.] [cite web | title=Overview of medically important antifungal azole derivatives | url=http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=358042&blobtype=pdf | format=pdf| publisher=PubMed | accessdate=2007-01-06 See page 6, /192, Clinical studies]
*Paclitaxel, a mitotic inhibitor used in cancer chemotherapy; [cite web | title=Abraxane in the treatment of ovarian cancer: the absence of hypersensitivity reactions | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16226797&query_hl=22&itool=pubmed_docsum | format=| publisher=PubMed | accessdate=2007-01-06]
*Sandimmune (cyclosporine injection, USP), an immunosuppressant drug widely used in connection with organ transplant to reduce the activity of the patient's immune system; [cite web | title=Sandimmune ingredients | url = http://dailymed.nlm.nih.gov/dailymed/search.cfm?startswith=sandimmune&x=10&y=6 |publisher=DailyMed | accessdate=2007-01-06]
*Nelfinavir mesylate, an HIV protease inhibitor; [cite web | title=Circulating Metabolites of the Human Immunodeficiency Virus Protease Inhibitor Nelfinavir in Humans: Structural Identification, Levels in Plasma, and Antiviral Activities | url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=90428 | format= | publisher=PubMed | accessdate=2007-01-06]
*Saperconazole, a triazole antifungal agent (contains Emulphor EL -719P, a castor oil derivative); [cite web | title=Saperconazole Therapy of Murine Disseminated Candidiasis: | url=http://www.pubmedcentral.nih.gov/pagerender.fcgi?tool=pmcentrez&pageindex=1&artid=284460 | format=| publisher=PubMed | accessdate=2007-01-06]
*Prograf, an immunosuppressive drug (contains HCO-60, polyoxyl 60 hydrogenated Castor oil);Fact|date=August 2007
*Xenaderm ointment, a topical treatment for skin ulcers is a combination of Balsam Peru, Castor oil, and trypsin; [cite web| url=http://www.healthpoint.com/divisions/tm/prodXenaderm.cfm |title=Product Information: XENADERM(TM) topical ointment, balsam peru, castor oil and trypsin topical ointment. Healthpoint,Ltd., San Antonio, TX, 2002|accessdate=2007-10-11] [cite web | title=Heparin - induced thrombocytopenia syndrome bullous lesions treated with trypsin - balsam of peru - castor oil ointment: a case study | url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16014993&query_hl=8&itool=pubmed_docsum | format=| publisher=PubMed | accessdate=2007-01-06]
*Aci-Jel, a gel used to create or maintain the acidity of the vagina (comprises acetic acid/oxyquinoline/ricinoleic acid - vaginal) [cite web | title=Aci-Jel (Vaginal Jelly) drug description - prescription drugs and medications at RxList | url=http://www.rxlist.com/cgi/generic/acijel.htm | format= | publisher=RxList | accessdate=2007-10-26]

Traditional or folk medicines

The use of cold pressed castor oil in folk medicine predates government regulations. Cold pressed castor oil is tasteless and odorless when pure. Uses include skin problems, burns, sunburns, skin disorders, skin cuts, and abrasions. Castor oil can also be used to draw out styes in the eye by pouring a small amount into the eye and allowing it to circulate around the inside of the eyelid. The oil is also used as a rub or pack for various ailments, including abdominal complaints, headaches, muscle pains, inflammatory conditions, skin eruptions, lesions, and sinusitis. A castor oil pack is made by soaking a piece of flannel in castor oil, then putting it on the area of complaint and placing a heat source, such as a hot water bottle, on top of it. This remedy was often suggested by the American Healing Psychic, Edgar Cayce, given in many healing readings in the early mid-1900s. [ [http://edgarcayce.org/health/database/aboutCastorOil.html What is Castor Oil?] . "Edgar Cayce's Association for Research Enlightenment, Inc."] Castor has been used to induce childbirth, but does not always work, and whether it works at all is disputed. While some women have used it effectively in this way for overdue pregnancies, others have used it without subsequently going into labor. The reason it does sometimes work to induce labor is that castor oil triggers cramping in the bowel (hence it being an effective laxative). Sometimes this cramping spreads to the uterus, and in an overdue pregnancy in which the mother's cervix is already effacing and partially dialated, this cramping can become labor contractions. Castor oil induced labor, however can be stressful on the mother and fetus as the cramping can be quite severe, causing irregularly spaced, very painful contractions, which can cause fetal distress. It also leaves the laboring woman quite dehydrated as a result of the vomiting and diarreah that are also effects of taking the recommended dose of castor oil for labor induction ( 2 oz, or about 8 tbsps). This leaves her without access to the energy she could otherwise derive from food or drink throughout her labor proccess. While these effects are by no means pleasant some women prefer this more natural method, to a chemical induction in a hospital. Using castor oil for induction is not recommended without consulting a medical practitioner and is not recommended in a complex pregnancy.

Industrial castor oil

Castor oil has numerous applications in transportation, cosmetics and pharmaceutical, and manufacturing industries, for example: adhesives, brake fluids [ cite web|url=http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0737879|title= Castor oil as a component of brake fluid|accessdate=2007-08-03] , caulks, dyes, electrical liquid dielectrics, humectants,cite web|url=http://whc-oils.com/castor-oil.html|title= Multiple uses of castor oil|accessdate=2007-08-02] hydraulic fluids, inks, lacquers, leather treatments, lubricating greases, machining oils, paints, pigments, polyurethane adhesives [cite journal| last=Azambuja | first =Maximiliano dos Anjos | coauthors =Dias, Antonio Alves | title =Use of castor oil-based polyurethane adhesive in the production of glued laminated timber beams| journal =Mat. Res. [online] | date= 2006, vol. 9, no. 3 | pages =287–291 | url =http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392006000300008&lng=en&nrm=iso | accessdate =2007-08-02] , refrigeration lubricants, rubbers, sealants, textiles, washing powders, and waxes.

Vegetable oils, due to their good lubricity and biodegradability are attractive alternatives to petroleum-derived lubricants, but oxidative stability and low temperature performance limit their widespread use. [cite web|url=http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=166442|title= Chemical modification to improve vegetable oil lubricants|accessdate=2007-08-02] Castor oil has better low temperature viscosity properties and high temperature lubrication than most vegetable oils, making it useful as a lubricant in jet, diesel, and race-car engines. [cite web | last =McGuire | first =Nancy
title =Taming the Bean | publisher =The American Chemical Society | date= 2004 | url =http://www.chemistry.org/portal/a/c/s/1/feature_pro.html?id=c373e9faf603d46b8f6a4fd8fe800100 | accessdate =2007-08-02 ] However, castor oil tends to form gums in a short time, and its use is therefore restricted to engines that are regularly rebuilt, such as motorcycle race engines. Biodegradability results in decreased persistence in the environment (relative to petroleum-based lubricants [cite web | url=http://www.eia.doe.gov/kids/energyfacts/sources/non-renewable/oil.html#Environment | title=Petroleum Oil and the Environment | publisher=DOE | accessdate=2006-12-28] ) in case of an accidental release. The lubricants company Castrol took its name from castor oil.

Since it is has a relatively high dielectric constant (4.7), highly refined and dried castor oil is sometimes used as a dielectric fluid within high performance high voltage capacitors.

Castor oil is the raw material for the production of a number of chemicals, notably sebacic acid, undecylenic acid, nylon-11. A review listing numerous chemicals derived from castor oil is available. [cite journal |last=Ogunniyi |first=D.S. |authorlink= |coauthors= |year=2006 |month= June|title=Castor oil: A vital industrial raw material |journal=Bioresource Technology |volume=97 |issue=9 |pages= 1086–1091|id= |url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V24-4G7NSTG-3&_user=432163&_coverDate=06%2F30%2F2006&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000020718&_version=1&_urlVersion=0&_userid=432163&md5=fb81fe7480f87cd089cc1ff182a001fb |accessdate=2008-08-10 |quote=|doi=10.1016/j.biortech.2005.03.028 ]

Castor oil is the preferred lubricant for bicycle pumps, most likely because it doesn't dissolve natural-rubber seals. ["Here's a good tip: Instead of lubricating your pump with petroleum oil, which will rot the pump's rubber parts, use castor oil, available at your local drugstore." Jules Older, "Backroad and Offroad Biking" (Stackpole Books (August 2000)), ISBN 0811731502, ISBN 978-0811731508, at p. 37; viewable via Google Book Search [http://books.google.com/books?id=INNM7b2bQzkC&pg=PA35&dq=%22Jules+Older%22+%22Backroad+and+Offroad+Biking%22&sig=2u6-HyT5x1ON0ab8juHLYhguMw4 here] ]

Uses in early aviation and aeromodelling

Castor oil was the preferred lubricant for the early aviation powerplant design known as the rotary engine, such as the Gnome engines used in pre-World War I "pioneer aircraft", after that engine's widespread adoption for aviation in Europe in 1909, and was used almost universally by the rotary engines in World War I Allied aircraft.

The methanol-fuelled glow plug engines used for aeromodelling purposes, since their adoption in the model airplane hobby in 1948, have used castor oil as a dependable lubricant that is highly resistant to degradation when the engine has its fuel-air mixture "leaned out" for maximum engine speed. The aforementioned gummy residue problem can still be troublesome for aeromodelling powerplants lubricated with castor oil, however, usually resulting in eventual ball bearing replacement when the residue builds up too much within the engine's bearing races.

Castor biofuel farming started in 2008 in Ethiopia. Families in the Waletia and Goma Gofa regions of Ethiopia began by seeding castor beans for use in biodiesel. The initiative is run by energy company Global Energy Ethiopia, who are also conducting a research and development programme to create new varieties of castor with better yields. (Sub-Saharan Africa gateway, Science and Development Network website, 2008)

Use as a means of intimidation in Fascist Italy

In Fascist Italy under the regime of Benito Mussolini, castor oil was one of the tools of the blackshirts. [cite encyclopedia
title =Italy The rise of Mussolini
encyclopedia =Encyclopædia Britannica Online
volume =
pages =
publisher =Encyclopædia Britannica
date= 2007
url =http://www.britannica.com/eb/article-27762/Italy
accessdate =2007-08-03 ] [cite news
last =
first =
coauthors =
title =Benito's Birthday
work =
pages =
language =
publisher =Time, in partnership with CNN
date =Monday, Aug. 06, 1923
url =http://www.time.com/time/magazine/article/0,9171,716284,00.html?iid=chix-sphere
accessdate =2007-08-03 ] [cite book
last =Bosworth
first =R. J. B.
authorlink =
coauthors =
title =Mussolini
publisher =Arnold/Oxford Univ. Press
date= 2002
location =New York
pages =
url =
doi =
id =
isbn =0340731443 ] Political dissidents were force-fed large quantities of castor oil by Fascist paramilitary groups. This technique was said to have been originated by Gabriele D'Annunzio. Victims of this treatment would experience severe diarrhea and dehydration, often resulting in death. [ [http://www.straightdope.com/classics/a4_028.html The Straight Dope: Did Mussolini use castor oil as an instrument of torture? ] ]

Sometimes when the blackshirts wished to make sure that the victim would die rather than simply be badly disabled, they would mix gasoline with the castor oil.Fact|date=March 2008

It is said that Mussolini's power was backed by "the bludgeon and castor oil". In lesser quantities, castor oil was also used as an instrument of intimidation, for example to discourage civilians or soldiers who would call in sick either in the factory or in the military. Since its healing properties were widely exaggerated, abuse could be easily masked under pretense of a doctor's prescription. It took decades after Mussolini's death before the myth of castor oil as a panacea for a wide range of diseases and medical conditions was totally demystified, as it was also widely administered to pregnant women, elderly or mentally-ill patients in hospitals in the false belief that it had no negative side effects.

Linguistic connotations

Today the Italian terms "manganello" and "olio di ricino", even used separately, still carry strong political connotations. These words are still used to satirize patronizing politicians, or the authors of unpopular legislation. They should be used with caution in common conversation. The terms "Usare l'olio di ricino", ("to use castor oil") and "usare il manganello" ("use the bludgeon") mean "to coerce or abuse," and can be misunderstood in the absence of proper context.

See also

* Castor plant
* Castor wax

References

External links

*ICSC|1452|14

[http://www.scidev.net/en/sub-suharan-africa/news/sub-saharan-africa-news-in-brief-25-march-9-april.html Castor biofuel farming starts in Ethiopia]