Senna obtusifolia

''Senna obtusifolia'', known by the common names Chinese senna, American sicklepod, sicklepod, etc., is a plant in the genus '' Senna'', sometimes separated in the monotypic genus ''Diallobus''. It grows wild in North, Central, and South America, Asia, Africa, and Oceania, and is considered a particularly serious weed in many places. It has a long-standing history of confusion with ''Senna tora'' and that taxon in many sources actually refers to the present species.

In the traditional medicine of Eastern Asia, the seeds are called in Chinese ( simplified: ; traditional: ), ''gyeolmyeongja'' in Korean, and ''ketsumeishi'' in Japanese.

The green leaves of the plant are fermented to produce a high-protein food product called "kawal" which is eaten by many people in Sudan as a meat substitute. Its leaves, seeds, and root are also used in folk medicine, primarily in Asia. It is believed to possess a laxative effect, as well as to be beneficial for the eyes. As a folk remedy, the seeds are often roasted, then boiled in water to produce a tea. The plant's seeds are a commercial source of cassia gum, a food additive usually used as a thickener and named for the Chinese Senna's former placement in the genus '' Cassia''. Roasted and ground, the seeds have also been used as a substitute for coffee. In ''vitro'' cultures of ''S. obtusifolia'' such as hairy roots may be a source of valuable secondary metabolites with medical applications.

Names, taxonomy and identifier

''S. obtusifolia'' is known by a number of common names. Apart from "sicklepod", sickle-pod senna, rarely "Chinese senna" or even "American sicklepod", it is also called arsenic weed, foetid cassia, or wild senna.

It is also known locally by common names such as "coffee weed" (coffeeweed) or "java bean" (in Australia) or "coffee pod" (in the American South or West), although the terms "coffee weed" or "coffee pod" are ambiguous as they also apply to ''S. tora''. It may be called by the Hindi name "chakunda" in India, but this is also one of the names for ''S. tora''.

The scientific name means "blunt-leaved senna", with ''obtusifolia'' coming from Latin ''obtusus'' ("dull", "blunt") + ''folium'' ("leaf").

Names in its native range are also:
* Chinese: pinyin: (), though this could loosely apply to seeds of the ''Senna'' genus generally.
* Japanese: ("'' Ebisu'' grass": エビスグサ; 胡草; 恵比須草)
* Korean: (hangul: ; hanja: )
* Vietnamese: (from Hán tự: 決明子)
* Portuguese: (also used for '' Senna macranthera'' and others)
* Hindi:

Synonyms

Chinese senna has been treated under a wide range of scientific names. Some are synonyms of ''Senna obtusifolia'', others are names that have been applied to it in error. In addition, several of these names may also refer to related plants. In particular, the distinction between this species and ''Senna tora'' was fraught with errors and misunderstandings:
* ''Cassia humilis'' Collad.
:''Cassia humilis'' Steud. is a synonym of ''Chamaecrista kunthiana''
:''Cassia numilis'' Collad. is apparently a misprint and refers to ''Senna tora''
* ''Cassia obtusifolia'' L.
* ''Cassia tora'' auct. ''non'' L.
:''Cassia tora'' L. is a synonym of ''Senna tora''
* ''Cassia tora'' L. var. ''b'' Wight & Arn.
* ''Cassia tora'' L. var. ''humilis'' (Collad.) Collad.
* ''Cassia tora'' L. var. ''obtusifolia'' (L.) Haines
* ''Cassia toroides'' Raf.
* ''Cassia toroides'' Roxb.
* ''Diallobus falcatus'' Raf.
* ''Diallobus uniflorus'' Raf.
* ''Senna toroides'' Roxb.

Traditional Eastern medicine

The materia medica name for the seeds in Chinese is ( simplified: ; traditional: ). The medicinal seeds are also known by the equivalent Korean name ''gyeolmyeongja'' () in traditional Korean medicine, and by the Japanese name in ''kampō'' medicine.

The ''jue ming zi'' is used widely in Asia, including Southeast Asian countries such as Thailand, and its herbal tea is drunk instead of regular tea as a preventative for hypertension. It is also purported to have the ability to clear the eye. In Korea also, medicinal ''gyeolmyeongja'' is usually prepared as tea (''gyeolmyeongja-cha''. ‘sickle pod tea’).

''Senna tora'' (''Cassia tora'') is used similarly, and though distinguished in the Chinese market as the "little/lesser" variety or ''shao jue ming'' ) the Japanese government's harmacopoeia(''Nihon yakkyokuhō'') officially acknowledges both ''S. obtusifolia'' and ''S. tora'' to be commerced as ''ketsumeishi''.

The Japanese beverage , as the name suggests, was originally brewed from the seeds of the ''habusō'' or '' S. occidentalis'', but currently marketed ''habu-cha'' uses ''S. obtusifolia'' as substitute, since it is a higher-yielding crop.

Meat substitute

Kawal, a protein-rich meat substitute eaten in Sudan, is produced by crushing the leaves of the plant into a paste which is then traditionally fermented in an earthenware jar, buried in a cool place. The jar is dug up every three days and the contents mixed. After two weeks, the paste is removed and rolled into balls which are left to dry in the sun. They are usually cooked in stews with onions and okra.

See also

* Sicklepod tea
* ''Chamaecrista nomame'' - ''Chamaecrista'' sp. (Japanese: ''kawaraketsumei'' lit. ‘riverside sicklepod’)

References

Bibliography

* International Legume Database & Information Service (ILDIS) (2005)
Genera ''Cassia'' and ''Senna''
Version 10.01, November 2005. Retrieved 2007-12-17.
*

External links

Cassia Seed page
from ENaturalHealthCenter.com site


from Missouriplants.com site

{{Taxonbar, from=Q1378803

obtusifolia
Flora of North America
Flora of South America
Dietary supplements
Medicinal plants
Herbs
Plants described in 1753
Taxa named by Carl Linnaeus