Phytolacca americana
American Pokeweed (Phytolacca americana) is a large semi-succulent herbaceous perennial plant growing up to 10 feet (3 meters) in height. It is native to eastern North America, the Midwest, and the Gulf Coast, with more scattered populations in the far West. It is also known as Virginia poke,[1][2] American nightshade, cancer jalap, coakum, garget,[2] inkberry, pigeon berry,[1][2] pocan,[2] pokeroot,[1] pokeweed,[1] pokeberry,[1] redweed, scoke,[2] red ink plant and chui xu shang lu (in Chinese medicine).[1] Parts of this plant are highly toxic to livestock and humans, and it is considered a major pest by farmers. Nonetheless, some parts can be used as food, medicine or poison.
The plant has a large white taproot, green or red stems, and large, simple leaves. White flowers are followed by purple to almost black berries, which are a good food source for songbirds such as Gray Catbird, Northern Cardinal, Brown Thrasher, and Northern Mockingbird.
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Morphology
Plant Type: Perennial herbaceous plant which can reach a height of 10 feet, but is usually four to six feet. The stem is often red as the plant matures. Upright, erect central stem early in the season. Changes to a spreading, horizontal form later in the season with the weight of the berries. Plant dies back to roots each winter. Stem has chambered pith.[citation needed]
Leaves: The leaves are alternate with coarse texture with moderate porosity. Leaves can reach sixteen inches in length. Each leaf is entire. Leaves are medium green and smooth with what some characterize as an unpleasant odor.[citation needed]
Flowers: The flowers have 5 regular parts with upright stamens and are up to 0.2 inches wide. They have white petal-like sepals without true petals, on white pedicles and peduncles in an upright or drooping raceme, which darken as the plant fruits. Blooms first appear in early summer and continue into early fall.[citation needed]
Fruit: A shiny dark purple berry held in racemous clusters on pink pedicels with a pink peduncle. Pedicles without berries have a distinctive rounded five part calyx. Fruits are round with a flat indented top and bottom. Immature berries are green, turning white and then blackish purple.[citation needed]
Root: Thick central taproot which grows deep and spreads horizontally. Rapid growth. Tan cortex, white pulp, moderate number of rootlets. Transversely cut root slices show concentric rings. No nitrogen fixation ability.[3][1]
Habitat and range
Broadly distributed in fields and waste places, and usually found in edge habitats. The seeds do not require stratification and are dispersed by berry-feeding birds. Adapted to coarse or fine soils with moderate moisture, high calcium tolerance but low salinity tolerance, pH tolerance from 4.7-8. Grows well in sun or shade and readily survives fire due to its ability to resprout from the roots. In recent years the plant appears to have increased in populated places. Found in most of the United States except the Mountain States, Alaska and Hawaii.[1][4]
Known constituents
Triterpene saponins: Phytolaccoside A,B,C,D,E,F,G (esculentoside E), phytolaccagenin, jaligonic acid, esculentic acid, 3-oxo-30-carbomethoxy-23-norolean-12-en-28-oic acid, phytolaccagenic acid, oleanolic acid.[6]
Triterpene alcohols: alpha spinasterol, alpha spinasteryl-beta-D-glucoside, 6 palmityl-delta7-stigmasterol-delta-D-glucoside, 6 palmytityl-alpha-spinasteryl-6-D-glucoside.
Other: phytolaccatoxin, canthomicrol, astragalin, protein PAP-R, mitogen (Pokeweed mitogen, PMW, a series of glycoproteins), caryophyllene, lectins, tannin, starch.
Nutritional Information per 100 grams dry weight of shoots:[3]
- Protein: 31g; Fat: 4.8g; Carbohydrate: 44g; Fibre: 0g; Ash: 20.2g;
- Minerals - Calcium: 631 mg; Phosphorus: 524 mg; Iron: 20.2 mg; Magnesium: 0 mg; Sodium: 0 mg; Potassium: 0 mg; Zinc: 0 mg;
- Vitamins - A: 62 mg; Thiamine (B1): 0.95 mg; Riboflavin (B2): 3.93 mg; Niacin: 14.3 mg; B6: 0 mg; C: 1619 mg.
Standardization: Phytolacca is not generally standardized since it is not marketed to public and various properties are being considered for standardization for different uses. For example Phytolaccoside A,B, C et al. from leaves are being considered for antiviral use and Pokeweed antiviral protein, with subtypes taken from leaves in different seasons for AIDS. Oleanolic acid would be the constituent of choice for standardizing for the purposes of cancer since it is present in an ethanol root extract and has significant anticancer properties, for several types of carcinoma as well as leukemia.[7][8]
Toxicity
Pokeweed poisonings were common in eastern North America during the 19th century, especially from the use of tinctures as antirheumatic preparations and from ingestion of berries and roots that were mistaken for parsnip, Jerusalem artichoke, or horseradish.[9] Deaths are currently uncommon, although there are cases of emesis and catharsis, but at least one death of a child who consumed crushed seeds in a juice has occurred.[citation needed]
The toxic components of the plant are saponins based on the triterepene genins phytolaccagenin, jaligonic acid, phytolaccagenic acid (phytolaccinic acid), esculentic acid, and pokeberrygenin.[6] These include phytolaccosides A, B, D, E, and G, and phytolaccasaponins B, E, and G. Phytolaccigenin causes hemagglutination.[10][11]
Uses
Food uses
Although the seeds are highly toxic, the berries are often cooked into a jelly or pie, and seeds are strained out or pass through unless bitten. Cooking is believed to inactivate toxins in the berries by some and others attribute toxicity to the seeds within the berries. The leaves of young plants are sometimes collected as a spring green potherb and eaten after repeated blanchings. Shoots are also blanched with several changes of water and eaten as a substitute for asparagus. They become cathartic as they advance to maturity.[12] The cooked greens are sold commercially in the South, but any food use of the plant is controversial because of toxins in the plant.[citation needed]
All parts of pokeweed are toxic including the raw aboveground leaves sprouting in the early spring.[3] The poisonous principles are found in highest concentrations in the rootstock, less in the mature leaves and stems, and least in the fruits. (Green fruits are slightly more toxic) Young leaves, if collected before acquiring a red color, are edible if boiled for 5 minutes, rinsed, and reboiled. Berries are toxic when raw but cooked juice is edible (the seeds remain toxic after cooking). However, it may be difficult to identify exactly when leaves have no red color whatsoever; an incorrect picking may result in a poisoning. In a traditional Cherokee recipe for fried poke stalks, young stalks are harvested while still tender, peeled to remove most of the toxin, washed, then cut into pieces and fried like okra with cornmeal.
Young pokeweed leaves can be boiled three times to reduce the toxin, discarding the water after each boiling. The result is known as poke salit, or poke salad, and is occasionally available commercially.[4] Many authorities advise against eating pokeweed even after thrice boiling, as traces of the toxin may still remain. It should never be eaten uncooked. For many decades, poke salad has been a staple of southern U.S. cuisine, despite campaigns by doctors who believed pokeweed remained toxic even after being boiled. The lingering cultural significance of poke salad can be found in the 1969 hit song "Polk Salad Annie," written and performed by Tony Joe White, and famously covered by Elvis Presley, as well as other bands including the El Orbits of Houston, Texas. Pokeberry juice is added to other juices for jelly by those who believe it can relieve the pain of arthritis. There are currently four known poke sallet festivals held annually. They are in Gainesboro, Tennessee; Blanchard, Louisiana; Harlan, Kentucky; and, Arab, Alabama.
Since pioneer times, pokeweed has been used as a folk remedy to treat many ailments. It can be applied topically or taken internally. Topical treatments have been used for acne and other ailments. Internal treatments include tonsillitis, swollen glands and weight loss. Dried berries were ingested whole as a treatment for boils, taken 1 berry per day for 7 days. Grated pokeroot was used by Native Americans as a poultice to treat inflammations and rashes of the breast. Independent researchers are investigating phytolacca's use in treating AIDS and cancer patients. Especially to those who have not been properly trained in its use, pokeweed should be considered dangerous and possibly deadly.
Ingestion of poisonous parts of the plant may cause severe stomach cramping, nausea with persistent diarrhea and vomiting, sometimes bloody, slow and difficult breathing, weakness, spasms, hypertension, severe convulsions, and death. However, consuming fewer than 10 uncooked berries is generally harmless to adults. Several investigators have reported deaths in children following the ingestion of uncooked berries or pokeberry juice. Severe poisonings have been reported in adults who ingested mature pokeweed leaves and following the ingestion of tea brewed from one-half teaspoonful of powdered pokeroot.
Pokeweed berries yield a red ink or dye, which was once used by aboriginal Americans to decorate their horses. Many letters written home during the American Civil War were written in pokeberry ink; the writing in these surviving letters appears brown. The red juice has also been used to symbolize blood, as in the anti-slavery protest of Benjamin Lay. A rich brown dye can be made by soaking fabrics in fermenting berries in a hollowed-out pumpkin.
Some pokeweeds are also grown as ornamental plants, mainly for their attractive berries; a number of cultivars have been selected for larger fruit panicles.
Pokeweeds are used as food plants by the larvae of some Lepidoptera species including Giant Leopard Moth.
Other uses
A patent has been filed to use poke toxins to control zebra mussels.[13]
The berries can be used as a natural dye.
Gallery
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References
- ^ a b c d e f g h i "USDA GRIN taxonomy". http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?28252.
- ^ a b c d e Bailey, L.H.; Bailey, E.Z.; the staff of the Liberty Hyde Bailey Hortorium (1976). Hortus third: A concise dictionary of plants cultivated in the United States and Canada. New York: Macmillan. ISBN 978-0-02-505470-7.
- ^ a b Phytolacca americana - Plants For A Future database report
- ^ PLANTS Profile for Phytolacca americana (American pokeweed) | USDA PLANTS
- ^ Chinese Herbal Medicine, Materia Medica 3rd Edition. Bensky, Dan; Steven Clavey, Erich Stoger. Eastland Press, 2004.
- ^ a b Kang SS, Woo WS (1980). "Triterpenes from the berries of Phytolacca americana". J Nat Prod 43 (4): 510–3. doi:10.1021/np50010a013.
- ^ Barbieri L, Aron GM, Irvin JD, Stirpe F (April 1982). "Purification and partial characterization of another form of the antiviral protein from the seeds of Phytolacca americana L. (pokeweed)". Biochem. J. 203 (1): 55–9. PMC 1158192. PMID 7103950. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1158192/.
- ^ HerbalGram: The Journal of the American Botanical Council.
- ^ Lewis WH, Smith PR (December 1979). "Poke root herbal tea poisoning". JAMA 242 (25): 2759–60. doi:10.1001/jama.242.25.2759. PMID 501875.
- ^ Tang W, Eisenbrand G. Chinese Drugs of Plant Origin: Chemistry, Pharmacology, and Use in Traditional and Modern Medicine . New York, NY: Springer-Verlag; 1992:765
- ^ Suga Y, Maruyama Y, Kawanishi S, Shoji J (1978). "Studies on the constituents of phytolaccaceous plants. I. On the structures of phytolaccasaponin B, E and G from the roots of Phytolacca americana L.". Chem Pharm Bull 26: 520–5.
- ^ [1] Harvey Wickes Felter and John Uri Lloyd 1898. King's American Dispensatory.
- ^ US 5252330 Method of controling zebra mussels with extract of Phytolacca dodecandra
- Elvin-Lewis, Memory P. F.; Lewis, Walter Hepworth (2003). Medical botany: plants affecting human health (2nd ed.). Chichester: John Wiley & Sons. p. 82. ISBN 0-471-62882-4.
- "Complete Pokeweed Information" from Drugs.com professional
