Adenia is a genus of flowering plants in the passionflower family Passifloraceae. It is distributed in the Old World tropics and subtropics.[1] The centers of diversity are in Madagascar, eastern and western tropical Africa, and Southeast Asia.[2] The genus name Adenia comes from "aden",[3] reported as the Arabic name for the plant by Peter Forsskål, the author of the genus.[4]

Adenia
Adenia pechuelii
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Passifloraceae
Subfamily: Passifloroideae
Tribe: Passifloreae
Genus: Adenia
Forssk.
Species

about 100, see text

Synonyms

Description

edit

All Adenia are perennial plants, but there are many different forms, including herbs, vines, shrubs, and trees.[5] Many are succulents and some are pachycauls. Some have fibrous root systems and some have tubers.[5] Adenia can be found in a wide variety of habitat types, from dry African deserts to wet Southeast Asian rainforests.[5] There are about 100 species in the genus.[6]

Adenia have alternately arranged leaves borne on petioles. There are two glands located near the attachment of the leaf blade to the petiole.[1] Most species are dioecious.[5] Inflorescences of a few to many flowers occur in the leaf axils. There is a stipe below the flower.[clarification needed] The calyx has five lobes and the five petals are usually smaller than the sepals and may be whitish or greenish. The male flower has five stamens. In the female flower these are reduced to staminodes. There are three styles tipped with stigmas that may be long-hairy to very woolly. The fruit is a red capsule. Each black seed has a fleshy aril.[1]

Adenia species can be difficult to identify and distinguish as individuals of a species can be variable. One plant can have leaves of varying shapes and sizes, and young and old specimens can have different leaf types. Some taxa are poorly represented in herbarium collections, leaving few examples to compare with new specimens. Records of some taxa lack descriptions of both (i.e. male and female) flower types. Many species only flower for a few weeks, and during this time they may also lose their leaves. Succulent plants can be difficult to properly collect and preserve.[2]

Cytology

edit

The chromosome count of Adenia is 2n = 24 or 2n = 48.[7]

Uses

edit

Several species are used in traditional African medicine. Various parts of A. cissampeloides are used to treat many conditions, including gastrointestinal problems, inflammation, pain, fever, malaria, leprosy, scabies, cholera, anemia, bronchitis, sexually transmitted diseases, menorrhagia, and mental illness.[8] It is used both as an abortifacient and to prevent miscarriage.[8] A. dinklagei leaves are ingested to treat palpitations. The leaves of A. tricostata are used to treat fever. The leaves or leaf sap of A. bequaertii are taken to treat headache, mental illness, and possession.[8] A. lobata stems are applied to sites of Guinea worm infection during extraction of the worm. It is also used as an enema and an aphrodisiac.[9]

A. cissampeloides is used as a fish poison and arrow poison. The red-colored sap is used as a cosmetic. The stems can be made into rope. The crushed twigs or smoke from burning roots can be used to calm honeybees during honey harvest.[8]

The leaves of A. cissampeloides are eaten as a vegetable in parts of Africa.[8]

A. digitata is cultivated as an ornamental plant for its very large, distinctive aboveground tuber.[10]

Toxicity

edit

Many Adenia are poisonous. They contain lectins such as lanceolin, stenodactylin, and volkensin, which are toxic to cells. They cause apoptosis, hemagglutination, inhibition of protein synthesis, and depurination of ribosomes and DNA.[11] Mouse experiments with small doses of lanceolin and stenodactylin, from A. lanceolata and A. stenodactyla, respectively, revealed that they are "amongst the most potent toxins of plant origin".[12]

The fruit of A. digitata has been used in Africa to commit homicide and suicide.[10]

Species

edit
 
Adenia fruticosa
 
Adenia hondala

The following is a list of all 106 species in this genus that are accepted by Plants of the World Online as of 3 July 2023 [13]

References

edit
  1. ^ a b c Adenia. Flora of China.
  2. ^ a b Hearn, David J. (2007). "Novelties in Adenia (Passifloraceae): Four New Species, a New Combination, a Vegetative Key, and Diagnostic Characters for Known Madagascan Species". Brittonia. 59 (4): 308–27. doi:10.1663/0007-196X(2007)59[308:NIAPFN]2.0.CO;2. JSTOR 30218764. S2CID 40598157.
  3. ^ Eggli, U.; Newton, L.E. (2004). Etymological Dictionary of Succulent Plant Names. Springer Berlin Heidelberg. p. 3. ISBN 978-3-540-00489-9. Retrieved 25 September 2018.
  4. ^ Peter Forsskål. Flora Aegyptiaco-Arabica. 1775. page 77
  5. ^ a b c d Hearn, David J. (2006). "Adenia (Passifloraceae) and its adaptive radiation: phylogeny and growth form diversification". Systematic Botany. 31 (4): 805–21. doi:10.1600/036364406779695933. JSTOR 25064211. S2CID 86541538.
  6. ^ "Adenia — the Plant List".
  7. ^ Melo, N. F. D., & Guerra, M. (2021). "The karyotype of Adenia and the origin of the base number x= 12 in Passifloroideae (Passifloraceae)." Anais da Academia Brasileira de Ciências, 93.
  8. ^ a b c d e Grace, O. M. and D. Fowler. 2007. Adenia cissampeloides (Planch. ex Hook.) Harms. Archived 8 May 2012 at the Wayback Machine In: Schmelzer, G. H. and A. Gurib-Fakim (Eds.) Prota 11(1): Medicinal Plants/Plantes médicinales 1. PROTA, Wageningen, Netherlands.
  9. ^ Zimudzi, C. 2007. Adenia lobata (Jacq.) Engl. Archived 22 February 2014 at the Wayback Machine In: Schmelzer, G. H. and A. Gurib-Fakim (Eds.) Prota 11(1): Medicinal Plants/Plantes médicinales 1. PROTA, Wageningen, Netherlands.
  10. ^ a b de Ruijter, A. 2007. Adenia digitata (Harv.) Engl. In: Schmelzer, G. H. and A. Gurib-Fakim (Eds.) Prota 11(1): Medicinal Plants/Plantes médicinales 1. PROTA, Wageningen, Netherlands.
  11. ^ Mercatelli D, Bortolotti M, Andresen V, et al. (May 2020). "Early Response to the Plant Toxin Stenodactylin in Acute Myeloid Leukemia Cells Involves Inflammatory and Apoptotic Signaling". Front. Pharmacol. 11: 630. doi:10.3389/fphar.2020.00630. PMC 7226368. PMID 32457623.
  12. ^ Stirpe F, Bolognesi A, Bortolotti M, et al. (July 2007). "Characterization of highly toxic type 2 ribosome-inactivating proteins from Adenia lanceolata and Adenia stenodactyla (Passifloraceae)". Toxicon. 50 (1): 94–105. doi:10.1016/j.toxicon.2007.02.020. PMID 17434551.
  13. ^ "Adenia Forssk". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 3 July 2023.

Further reading

edit