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| | #REDIRECT [[Brazil nut]] | | #REDIRECT [[Brazil nut]] |
| − | {{Taxobox
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| − | | color = lightgreen
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| − | | name = Brazil Nut
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| − | | status = VU
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| − | | status_system = iucn2.3
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| − | | image = Brazil Nut fruit.jpg
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| − | | image_width = 250px
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| − | | image_caption = Brazil Nut fruit
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| − | | regnum = [[Plant]]ae
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| − | | divisio = [[Flowering plant|Magnoliophyta]]
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| − | | classis = [[Magnoliopsida]]
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| − | | ordo = [[Ericales]]
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| − | | familia = [[Lecythidaceae]]
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| − | | genus = '''''Bertholletia'''''
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| − | | species = '''''B. excelsa'''''
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| − | | binomial = ''Bertholletia excelsa''
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| − | | binomial_authority = [[Alexander von Humboldt|Humb.]] & [[Aimé Bonpland|Bonpl.]]
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| − | }}
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| − | The '''Brazil Nut''' is a [[South America]]n [[tree]] ''Bertholletia excelsa'' in the family [[Lecythidaceae]]. It is the only species in the genus ''Bertholletia''. It is native to the [[Guianas]], [[Venezuela]], [[Brazil]], eastern [[Colombia]], eastern [[Peru]] and eastern [[Bolivia]]. It occurs as scattered trees in large forests on the banks of the [[Amazon River|Amazon]], [[Rio Negro]], and the [[Orinoco]]. The genus is named after the [[France|French]] chemist [[Claude Louis Berthollet]].
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| − | It is a large tree, reaching 30–45 m tall and 1–2 m trunk diameter, among the largest of trees in the [[Amazon Rainforest]]s. It may live for 500 years or more. The stem is straight and commonly unbranched for well over half the tree's height, with a large emergent crown of long branches above the surrounding canopy of other trees. The bark is grayish and smooth.
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| − | The [[leaf|leaves]] are dry-season [[deciduous]], alternate, simple, entire or crenate, oblong, 20–35 cm long and 10–15 cm broad. The [[flower]]s are small, greenish-white, in panicles 5–10 cm long; each flower has a two-parted, deciduous calyx, six unequal cream-colored petals, and numerous stamens united into a broad, hood-shaped mass.
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| − | ==Reproduction==
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| − | Brazil nuts only produce fruit in [[virgin forests]] (forests not previously disturbed by human activity), as forests that are not virgin usually lack an [[orchid]] that is indirectly responsible for the pollination of the flowers. The orchids produce a scent that attracts small male long-tongued [[euglossini|orchid bees]] (''[[Euglossa]]'' spp), as the male bees need that scent to attract females. Without the orchid, the bees cannot mate, and therefore the lack of bees means the fruit do not get pollinated. The Brazil Nut tree's yellow flowers can only be pollinated by an insect strong enough to lift the coiled hood on the flower and with tongues long enough to negotiate the complex coiled flower. The large female long-tongued orchid bee pollinates the Brazil Nut tree. If both the orchids and the bees are present, the [[fruit]] takes 14 months to mature after pollination of the flowers, and is a large capsule 10–15 cm diameter resembling a [[coconut]] [[endocarp]] in size and weighing up to 2 kg. It has a hard, woody shell 8–12 mm thick, and inside contains 8–24 triangular seeds 4–5 cm long (Brazil nuts) packed like the segments of an [[citrus|orange]]; it is not a true [[nut (fruit)|nut]] in the botanical sense. The capsule contains a small hole at one end, which enables large [[rodent]]s like the [[Common Agouti|Agouti]] to gnaw open the capsule. They then eat some of the nuts inside while burying others for later use; some of these are able to germinate to produce new Brazil Nut trees. Most of the seeds are "planted" by the Agoutis in shady places, and the young [[sapling]]s may have to wait years, in a state of dormancy, for a tree to fall and sunlight to reach it. It is not until then that it starts growing again. [[Capuchin monkey]]s have been reported to open Brazil nuts using a stone as an anvil.
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| − | ==Nomenclature==
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| − | [[Image:Brazil nuts.jpg|left|thumb|shelled Brazil nuts]]
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| − | Despite their name, the most significant exporter of Brazil nuts is not [[Brazil]] but [[Bolivia]], where they are called ''almendras''. In Brazil these nuts are called ''castanhas-do-Pará'', literally "chestnuts from [[Pará]]", but [[Acre (state)|Acre]]ans call them ''castanhas-do-Acre'' instead. Indigenous names include ''juvia'' in the Orinoco area, and ''sapucaia'' in Brazil. Though the term has largely fallen into disuse since the latter 20th century because of its inflammatory nature, a common slang term for the nuts in some regions of the [[United States]] was "[[nigger]]-toes".
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| − | [[Image:Brazilnut.jpg|right|thumb|Brazil nut]]
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| − | [[Image:Brazil Nut - Project Gutenberg eBook 11662.jpg|thumb|Depiction of the Brazil Nut in ''[[Scientific American]] Supplement'', No. 598, June 18, 1887]]
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| − | The [[Brazil nut effect]], where large items mixed with other smaller items (e.g. Brazil nuts mixed with [[peanut]]s) tend to rise to the top, is named after the species' large nuts.
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| − | ==Uses==
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| − | Nutritionally, Brazil nuts are rich in [[selenium]], although the amount of selenium varies greatly.<ref>{{cite journal |quotes= |last=Chang |first=Jacqueline C. |authorlink= |coauthors=Walter H. Gutenmann, Charlotte M. Reid, Donald J. Lisk |year=1995 |month= |title=Selenium content of Brazil nuts from two geographic locations in Brazil |journal=Chemosphere |volume=30 |issue=4 |pages=801-802 |id=0045-6535 }}</ref> They are also a good source of [[magnesium]] and [[thiamine]]. The Brazil nut, in addition, is known as one of the world's most radioactive foods, due to the tree's accumulation of [[radium]] from the soil into the nut. It has been estimated that the concentration of radium in the Brazil nut is 1,000 times higher than in other foods.
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| − | Some research has suggested that selenium intake is correlated with a reduced risk of prostate cancer.<ref>Klein EA, Thompson IM, Lippman SM, Goodman PJ, Albanes D, Taylor PR, Coltman C., "SELECT: the next prostate cancer prevention trial. Selenum and Vitamin E Cancer Prevention Trial.", J Urol. 2001 Oct;166(4):1311-5. [PMID 11547064]</ref> This has led some commentators to recommend the consumption of brazil nuts as a protective measure.<ref>Cancer Decisions Newsletter Archive, ''Selenium, Brazil Nuts and Prostate Cancer'', [http://www.cancerdecisions.com/121001.html] last accessed 8 March 2007</ref>. Subsequent studies have shown that the effects of selenium on prostate cancer are inconclusive.<ref>Peters U, Foster CB, Chatterjee N, Schatzkin A, Reding D, Andriole GL, Crawford ED, Sturup S, Chanock SJ, Hayes RB. "Serum selenium and risk of prostate cancer-a nested case-control study." Am J Clin Nutr. 2007 Jan;85(1):209-17. [PMID 17209198]</ref>
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| − | Brazil nuts are 14% protein, 11% carbohydrates, and 67% fat. The fat breakdown is roughly 25% [[Saturated fat|saturated]], 41% [[Monounsaturated fat|monounsaturated]], and 34% [[Unsaturated fat|polyunsaturated]]. The saturated fat content of Brazil nuts is among the highest of all nuts, surpassing even [[macadamia nut]]s. Because of the resulting rich taste, Brazil nuts can often substitute for macadamia nuts or even [[coconut]]s in recipes. The high fat content of the nuts results in their not keeping well, and particularly, shelled Brazil nuts soon become rancid. The nuts are also pressed for oil; as well as for food use, Brazil nut oil is also used as a lubricant in [[clock]]s and for making [[artist|artists']] [[paint]]s.
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| − | ===Effects of harvesting===
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| − | Brazil nuts for international trade come entirely from wild collection rather than from farms. This has been touted as a model for generating income from a [[Tropical and subtropical moist broadleaf forests|tropical forest]] without destroying it.
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| − | Analysis of tree ages in areas that are harvested show that moderate and intense gathering takes so many seeds that not enough are left to replace older trees as they die. Sites with light gathering activities had many young trees, while sites with intense gathering practices had hardly any young trees.<ref>
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| − | http://dx.doi.org/10.1016/j.tree.2004.03.022</ref>
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| − | Statistical tests were done to determine what environmental factors could be contributing to the lack of younger trees. The most consistent effect was found to be the level of gathering activity at a particular site. A [[Computer simulation|computer model]] predicting the size of trees where people picked all the nuts matched the tree size data that was gathered from physical sites that had heavy harvesting.
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| − | ==See also==
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| − | *[[Offici
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| − | al list of endangered flora of Brazil]]
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| − | ==References and external links==
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| − | <div class="references-small">
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| − | <references />
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| − | </div>
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| − | * {{IUCN2006|assessors=Americas Regional Workshop (Conservation & Sustainable Management of Trees, Costa Rica, November 1996)|year=1998|id=32986|title=Bertholletia excelsa|downloaded=09 May 2006}} Listed as Vulnerable (VU A1acd+2cd v2.3)
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| − | * {{cite journal | author=Peres, C.A. et al. | title=Demographic threats to the sustainability of Brazil nut exploitation | journal=Science | volume=302 | issue=Dec. 19 | year=2003 | pages=2112-2114}}
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| − | * [http://www.bertholletia.org/bertholletia/ Brazil Nut homepage]
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| − | {{commons|Bertholletia excelsa}}
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| − | * [http://www.orau.org/PTP/collection/consumer%20products/brazilnuts.htm Radioactivity of Brazil nuts]
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| − | * [http://www.nybg.org/bsci/braznut/ New York Botanical Gardens Brazil Nuts Page]
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| − | * [http://news.bbc.co.uk/2/hi/science/nature/6298997.stm Aflotoxins in unshelled Brazil nuts]
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| − | [[Category:Crops originating from the Americas]]
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| − | [[Category:Edible nuts and seeds]]
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| − | [[Category:Lecythidaceae]]
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| − | [[Category:Trees of Brazil]]
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| − | [[Category:Trees of Bolivia]]
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| − | [[Category:Trees of Colombia]]
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| − | [[Category:Trees of Guyana]]
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| − | [[Category:Trees of Peru]]
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| − | [[Category:Trees of Venezuela]]
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| − | [[Category:Trees of the Amazon]]
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| − | [[Category:Tropical agriculture]]
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