Boerhavia diffusa
Introduction '''''Boerhavia diffusa''''' is a species of flowering plant in the four o'clock family which is commonly known as '''punarnava''' (meaning that which rejuvenates or renews the body in Ayurveda), '''red spiderling''', '''spreading hogweed''', or '''tarvine'''. It is taken in herbal medicine for pain relief and other uses. The leaves of ''Boerhavia diffusa'' are often used as a green vegetable in many parts of India.
Description Fruit of ''B. diffusa'' stuck to face of juvenile sooty tern ''Boerhavia diffusa'' is widely dispersed, occurring throughout India, the Pacific, and southern United States. Flowers are small, around 5 mm in diameter. Pollens are round, roughly 65 microns in diameter. Pollen This wide range is explained by its small fruit, which are very sticky and grow a few inches off the ground, ideally placed to latch on to small migratory birds as they walk by. '''Habit'''A creeping, perennial, much-branched herb with stout fusi form roots. '''Stem'''Branches divaricate, stem purplish, thickened at nodes. '''Leaves'''Opposite, oblique, ovate or sub orbicular, rounded, entire, margins slightly pinkish, wavy, lower surface with small, white scales, base rounded. '''Inflorescence'''Small umbels forming Corymbose, axillary and terminal panicle. '''Flowers'''*Bracteoles, acute. Perianth -tube constricted above the ovary, limb funnel-shaped, dark-pink, with 5 vertical bands outside. *Stamens 2 or 3, slightly exserted, unequal. *Ovary superior, oblique, ovule 1, erect, stigma. '''Fruit'''Achene rounded, 6-ribbed. '''Seed'''Minute, albuminous with endosperm. Embryo curved.
Distribution A true and accurate accounting of the native range of ''Boerhavia diffusa'' has not been determined. However, it is very widespread, and has become naturalized in many places. It is believed to be a native plant to the following places in:*'''Africa''' —Botswana, Egypt, Eswatini, Ghana, Kenya, Liberia, Malawi, Mozambique, Namibia, Nigeria, Rwanda, Senegal, Sierra Leone, Somalia, South Africa (Eastern Cape, Gauteng, KwaZulu-Natal, Limpopo, Mpumalanga, Northern Cape provinces), Tanzania, Togo, Uganda, Zambia, and Zimbabwe. *'''Asia''' —Bangladesh, Sri Lanka, Burma, Cambodia, China (Fujian, Guangdong, Guangxi, Guizhou, Hainan, Sichuan, and Yunnan provinces), India, Indonesia, Japan (Ryukyu Islands), Laos, Malaysia, Nepal, Pakistan (Punjab, Sind, Balochistan, Gilgit Baltistan), the Philippines, Southern Taiwan, Thailand, and Vietnam. Also, on the Arabian Peninsula in Oman, Saudi Arabia, and the United Arab Emirates, and Yemen (Socotra). *'''North America''' —Mexico, and the U.S. (in the states of Florida, Georgia, and South Carolina). *'''Caribbean''' — Anguilla, the Bahamas, the Cayman Islands, Cuba, Dominica, Grenada, Hispaniola (Dominican Republic and Haiti), Jamaica, Montserrat, the Netherlands Antilles (Saba), Puerto Rico, Saint Lucia, Saint Vincent and the Grenadines, and both the British and the U.S. Virgin Islands. *'''South America''' —Argentina, Belize, Bolivia, Chile, Costa Rica, Ecuador, French Guiana, Guatemala, Guyana, Nicaragua, Panama, Paraguay, Peru, Suriname, Uruguay, and Venezuela. *'''South Pacific''' —Fiji, and New Caledonia.
Economic importance ''B. diffusa'' is widely used as a green leafy vegetable in many Asian and African countries. ''B. diffusa'' can be used as a fodder for livestock, but has the potential for contaminating seed stocks, and may harbor pathogens for certain crops, such as eggplants.
Chemistry Boerhavia G and Boerhavia H are two rotenoids isolated from ''B. diffusa''. A quinolone alkaloid, lunamarine, isolated from ''B. diffusa'' has shown some ''in vitro'' anticancer, antiestrogenic, immunomodulatory, and anti-amoebic activity (particularly against ''Entamoeba histolytica'').The plant contains a protein called BDP-30, presumably a ribosome-inactivating protein.
References
External links * Tropical Plant Database* Boerhavia diffusa on ibiblio* Contains a detailed monograph on ''Boerhavia diffusa'' (Punarnava) as well as a discussion of health benefits and usage in clinical practice. Available online at https://web.archive.org/web/20110616192944/http://www.toddcaldecott.com/index.php/herbs/learning-herbs/323-punarnava