Tribulus terrestris

Tribulus terrestris
Leaves and flower
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Zygophyllales
Family:	Zygophyllaceae
Genus:	Tribulus
Species:	T. terrestris
Binomial name
Tribulus terrestris L.[1]
Varieties
Tribulus terrestris var. bicornutus Tribulus terrestris var. inermis Tribulus terrestris var. robustus Tribulus terrestris var. terrestris

Tribulus terrestris is a flowering plant in the family Zygophyllaceae, native to warm temperate and tropical regions of the Old World in southern Europe, southern Asia, throughout Africa, and Australia.^[2] It can thrive even in desert climates and poor soil. Like many weedy species, this plant has many common names, including bindii,^[3] bullhead,^[4] burra gokharu, caltrop,^[1] cat's head,^[1][3] devil's eyelashes,^[5] devil's thorn,^[1][5] devil's weed,^[1] goathead,^[1] puncturevine,^[1] and tackweed.^[6]

Growth

"Goathead" fruit

Thumbtack-like Tribulus terrestris nutlets are a hazard to bicycle tires.

It is a taprooted herbaceous perennial plant that grows as a summer annual in colder climates. The stems radiate from the crown to a diameter of about 10 cm to over 1 m, often branching. They are usually prostrate, forming flat patches, though they may grow more upwards in shade or among taller plants. The leaves are pinnately compound with leaflets less than 6 mm (a quarter-inch) long. The flowers are 4–10 mm wide, with five lemon-yellow petals. A week after each flower blooms, it is followed by a fruit that easily falls apart into four or five single-seeded nutlets. The nutlets or "seeds" are hard and bear two to three sharp spines, 10 mm long and 4–6 mm broad point-to-point. These nutlets strikingly resemble goats' or bulls' heads; the "horns" are sharp enough to puncture bicycle tires and to cause painful injury to bare feet.^[7]

Etymology

The Latin name tribulus originally meant the caltrop (a spiky weapon), but in Classical times already the word meant this plant as well.^[8]

Cultivation and uses

The plant is widely naturalised in the Americas and also in Australia south of its native range. In some states in the United States, it is considered a noxious weed and an invasive species.^[1]

It has been reported that the seeds or nutlets have been used in homicidal weapons in southern Africa; murderers smear them with the poisonous juice of Acokanthera venenata and put them where victims are likely to step.^[7]

Dietary supplement

T. terrestris is now being promoted as a booster for the purpose of increasing sex drive. Its use for this purpose originated from a Bulgarian study conducted in the 1970s, which found effects on free testosterone and luteinizing hormone in men belonging to infertile couples.^{[citation needed]} A research review conducted in 2000 stated that the lack of data outside of this study prevents generalizing to healthy individuals. ^[9]

The extract is claimed to increase the body's natural testosterone levels and thereby improve male sexual performance and help build muscle. Its purported muscle-building potential was popularized by American IFBB bodybuilding champion Jeffrey Petermann in the early 1970s. However, T. terrestris has consistently failed to increase testosterone levels in controlled studies.^[10][11][12] It has also failed to demonstrate strength-enhancing properties.^[13]

Tribulus has been shown to enhance sexual behaviour in an animal model.^[14] It appears to do so by stimulating androgen receptors in the brain.

Some body builders use T. terrestris as post cycle therapy or "PCT".^{[citation needed]} After they have completed an anabolic-steroid cycle, they use it under the assumption that it will restore the body's natural testosterone levels.

Medicinal uses

In traditional Chinese medicine Tribulus terrestris is known under the name bai ji li (白蒺藜). According to Bensky and Clavey, 2004 (Materia medica 3rd edition, pp. 975–976) Tribulus terrestris is ci ji li (刺蒺藜). "Confusion with Astragali complanati Semen (sha yuan zi) originally known as white ji li (白蒺藜 bai ji li), led some writers to attribute tonifying properties to this herb..."

Tribulus terrestris has long been a constituent in tonics in Indian ayurveda practice, where it is known by its Sanskrit name, "gokshura/ sarrata"^[15] It is also used as an aphrodisiac, diuretic and nervine in Ayurveda, and in Unani, another medical system of India.

Animal studies in rats, rabbits and primates have demonstrated that administration of Tribulus terrestris extract can produce statistically significant increases in levels of testosterone, dihydrotestosterone and dehydroepiandrosterone,^[16] and produces effects suggestive of aphrodisiac activity.^[14] On the other hand, one recent study found that T. terrestris caused no increase in testosterone or LH in young men,^[17] and another found that a commercial supplement containing androstenedione and herbal extracts, including T. terrestris, was no more effective at raising testosterone levels than androstenedione alone.^[18]

The active chemical in T. terrestris is likely to be protodioscin (PTN).^[19] In a study with mice, Tribulus was shown to enhance mounting activity and erection better than testosterone cypionate,^{[citation needed]} However, testosterone cypionate is a synthetic ester of testosterone engineered for its longer activity, rather than an immediate effect. Testosterone cypionate has a half-life of 8 days and is administereed every 2–4 weeks in humans for testosterone replacement.^[20] The proerectile aphrodisiac properties were concluded to likely be due to the release of nitric oxide from the nerve endings innervating the corpus cavernosum penis.^{[citation needed]} Also, T. terrestris was shown to have strong inhibitory activity on COX-2.^[21]

Adverse effects from supplementation with Tribulus terrestris are rare and tend to be insignificant.^{[citation needed]} However, some users report an upset stomach, which can usually be counteracted by taking it with food.^[22] Another rare side effect which has been reported is gynaecomastia,^[23] which while potentially problematic does tend to support the purported androgenic-anabolic effects of this plant, if it really was T. terrestris that caused it and not androgens, as the source doesn't say that the product was tested in order to detect what chemicals it contained.

Eradication

Typical habit of Tribulus terrestris

Where this is a non-indigenous species, eradication methods are often sought after. There are both biological and herbicidal solutions to the problem, but neither of them provide a solution which is both quick and long-lasting, because T. terrestris seeds remain viable for up to 3–7 years on average.

Physical

In smaller areas, puncture vine is best controlled with manual removal using a hoe to cut the plant off at its taproot. While this is effective, removing the entire plant by gripping the taproot, stem or trunk and pulling upward to remove the taproot is far more effective. This requires monitoring the area and removing the weed throughout the preseeding time (late spring and early summer in many temperate areas). This will greatly reduce the prevalence of the weed the following year. Mowing is not an effective method of eradication, because the plant grows flat against the ground.

Another avenue of physical eradication is to crowd out the opportunistic weed by providing good competition from favorable plants. Aerating compacted sites and planting competitive desirable plants including broad-leaved grasses such as St Augustine can reduce the impact of puncture vine by reducing resources available to the weed.

Chemical

Chemical control is generally recommended for home control of puncture vine. There are few pre-emergent herbicides that are effective. Products containing oryzalin, benefin, or trifluralin will provide partial control of germinating seeds. These must be applied prior to germination (late winter to midspring).

After plants have emerged from the soil (postemergent), products containing 2,4-dichlorophenoxyacetic acid ("2,4-D"), glyphosate, and dicamba are effective on puncture vine. Like most postemergents they are more effectively maintained when caught small and young. Dicamba and 2,4-D will cause harm to most broad-leaved plants so the user should take care to avoid over-application. They can be applied to lawns without injuring the desired grass. Glyphosate will kill or injure most plants so it should only be used as spot treatments or on solid stands of the weed.

Another product from DuPont called Pastora is highly effective, but expensive and not for lawn use.

Biological

Two weevils, Microlarinus lareynii and M. lypriformis, native to India, France, and Italy, were introduced into the United States as biocontrol agents in 1961. Both species of weevils are available for purchase from biological suppliers, but purchase and release is not often recommended because weevils collected from other areas may not survive at the purchaser's location.

Microlarinus lareynii is a seed weevil that deposits its eggs in the young burr or flower bud. The larvae feed on and destroy the seeds before they pupate, emerge, disperse, and start the cycle over again. Its life cycle time is 19 to 24 days. Microlarinus lypriformis is a stem weevil that has a similar life cycle, excepting the location of the eggs, which includes the undersides of stems, branches, and the root crown. The larvae tunnel in the pith where they feed and pupate. Adults of both species overwinter in plant debris. Although the stem weevil is slightly more effective than the seed weevil when each is used alone, the weevils are most effective if used together and the puncture vine is moisture-stressed.

Phytochemistry

Two alkaloids that seem to cause limb paresis (staggers) in sheep that eat Tribulus terrestulis are the beta-carboline alkaloids harman (harmane) and norharman (norharmane).^[24] The alkaloid content of dried foliage is about 44 mg/kg.^[24]

References

1. ^ ^{a b c d e f g h} "Tribulus terrestris information from NPGS/GRIN". www.ars-grin.gov. http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?100965. Retrieved 2008-03-18. 
2. ^ "Zygophyllaceae". Council of Heads of Australasian Herbaria. http://www.chah.gov.au/chah/apc/interim/Zygophyllaceae.pdf. Retrieved 2010-03-13. 
3. ^ ^{a b} "Caltrop - Tribulus terrestris". Weeds Australia. National Weeds Management Facilitator. http://www.weeds.org.au/cgi-bin/weedident.cgi?tpl=plant.tpl&ibra=all&card=H64. Retrieved 2009-03-10. 
4. ^ USDA PLANTS database
5. ^ ^{a b} Hyde, M.A. & Wursten, B. (2011). Flora of Mozambique
6. ^ North Dakota Department of Agriculture (no date). "Puncturevine (Tribulus terrestris)". http://www.agdepartment.com/noxiousweeds/pdf/Puncturevine.pdf. Retrieved 2 sept 2011. 
7. ^ ^{a b} Tribulus terrestris in BoDD – Botanical Dermatology Database
8. ^ Charlton T. Lewis, Charles Short, A Latin Dictionary
9. ^ Bucci LR (2000). "Selected herbals and human exercise performance". The American journal of clinical nutrition 72 (2 Suppl): 624S–36S. PMID 10919969. 
10. ^ Brown GA, Vukovich MD, Reifenrath TA, Uhl NL, Parsons KA, Sharp RL, King DS (2000). "Effects of anabolic precursors on serum testosterone concentrations and adaptations to resistance training in young men". International Journal of Sport Nutrition and Exercise Metabolism 10 (3): 340–59. PMID 10997957. 
11. ^ Brown GA, Vukovich MD, Martini ER, Kohut ML, Franke WD, Jackson DA, King DS (2001). "Endocrine and lipid responses to chronic androstenediol-herbal supplementation in 30 to 58 year old men". J Am Coll Nutr 20 (5): 520–8. PMID 11601567. 
12. ^ Neychev VK, & Mitev VI. (2005). "The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men". Journal of Ethnopharmacology 101 (1-3): 319–23. doi:10.1016/j.jep.2005.05.017. PMID 15994038. 
13. ^ Rogerson S, Riches CJ, Jennings C, Weatherby RP, Meir RA, Marshall-Gradisnik SM. (2007). "The Effect of Five Weeks of Tribulus terrestris Supplementation on Muscle Strength and Body Composition During Preseason Training in Elite Rugby League Players". The Journal of Strength & Conditioning Research 21 (2): 348–53. doi:10.1519/R-18395.1. PMID 17530942. 
14. ^ ^{a b} Gauthaman K, Adaikan PG, Prasad RN. (2002). "Aphrodisiac properties of Tribulus Terrestris extract (Protodioscin) in normal and castrated rats". Life Sciences 71 (12): 1385–96. doi:10.1016/S0024-3205(02)01858-1. PMID 12127159. 
15. ^ (2001). The Ayurvedic Pharmacopoeia of India, Ministry of Health & Family Welfare, Government of India, Department of Indian System of Medicine & Homoeopathy. Vol 1, Part 1: 260.
16. ^ Gauthaman K, Ganesan AP (Jan 2008). "The hormonal effects of Tribulus terrestris and its role in the management of male erectile dysfunction—an evaluation using primates, rabbit and rat". Phytomedicine 15 (1-2): 44–54. doi:10.1016/j.phymed.2007.11.011. PMID 18068966. 
17. ^ Neychev VK, Mitev VI (Oct 2005). "The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men". Journal of Ethnopharmacology 101 (1-3): 319–23. doi:10.1016/j.jep.2005.05.017. PMID 15994038. 
18. ^ Brown GA, Vukovich MD, Reifenrath TA, et al. (Sep 2000). "Effects of anabolic precursors on serum testosterone concentrations and adaptations to resistance training in young men". International Journal of Sport Nutrition and Exercise Metabolism 10 (3): 340–59. PMID 10997957. 
19. ^ Gauthaman K, Ganesan AP, Prasad RN (2003). "Sexual effects of puncturevine (Tribulus terrestris) extract (protodioscin): an evaluation using a rat model". Journal of Alternative and Complementary Medicine 9 (2): 257–65. doi:10.1089/10755530360623374. PMID 12804079. 
20. ^ "National Institutes of Health". http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=2268. Retrieved April 24, 2010 
21. ^ Hong CH, Hur SK, Oh OJ, Kim SS, Nam KA, Lee SK (2002). "Evaluation of natural products on inhibition of inducible cyclooxygenase (COX-2) and nitric oxide synthase (iNOS) in cultured mouse macrophage cells.". J. Ethnopharmacol 83 (1-2): 153–159. 
22. ^ Tribulus Terrestris – Supplements, accessed May 17, 2006
23. ^ Jameel JK, Kneeshaw PJ, Rao VS, Drew PJ (Oct 2004). "Gynaecomastia and the plant product "Tribulis terrestris"". Breast 13 (5): 428–430. doi:10.1016/j.breast.2003.10.013. PMID 15454201. 
24. ^ ^{a b} Bourke CA, Stevens GR, Carrigan MJ (Jul 1992). "Locomotor effects in sheep of alkaloids identified in Australian Tribulus terrestris". Australian Veterinary Journal 69 (7): 163–165. doi:10.1111/j.1751-0813.1992.tb07502.x. PMID 1445080. 

External links

• Germplasm Resources Information Network: Tribulus terrestris
• Flora Europaea: native distribution in Europe
• Page on T. terrestris at the Global Compendium of Weeds
• Page from the U.S. Department of Agriculture's PLANTS database
• Tribulus terrestris List of Chemicals (Dr. Duke's Databases)