Sesquiterpene lactones (SLs) are a class of sesquiterpenoids that contain a

lactone Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the co ...

ring. They are most often found in plants of the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae ...

(daisies, asters). Other plant families with SLs are Umbelliferae (celery, parsley, carrots) and Magnoliaceae (magnolias). A collection of colorless, lipophilic solids, SLs are a rich source of drugs. They can be allergenic and toxic in grazing livestock causing severe neurological problems in horses. Some are also found in corals such as ''

Maasella edwardsi ''Maasella'' is a genus of soft coral in the family Paralcyoniidae. It is monotypic, with only a single species, ''Maasella edwardsi''. Usually of greenish brown or golden brown color, each polyp has eight pinnate tentacles. This soft coral is ...

''.

Types

Sesquiterpene lactones can be divided into several main classes including

germacranolide Germacranolides are a group of natural chemical compounds classified as sesquiterpene lactone Sesquiterpene lactones (SLs) are a class of sesquiterpenoids that contain a lactone ring. They are most often found in plants of the family Asteraceae ( ...

s, heliangolides, guaianolides, pseudoguaianolides, hypocretenolides, and eudesmanolides.

Examples

Artemisinin, a new, highly-effective anti-

malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or deat ...

l compound, is a sesquiterpene lactone found in '' Artemisia annua''.

Lactucin Lactucin is a bitter substance that forms a white crystalline solid and belongs to the group of sesquiterpene lactones. It is found in some varieties of lettuce and is an ingredient of lactucarium. It has been shown to have analgesic and sedativ ...

, desoxylactucin, lactucopicrin, lactucin-15-oxalate, lactucopicrin-15-oxalate are some of the most prominent found in

lettuce Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of foo ...

and

spinach Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to central and western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common edible vegetable consumed eith ...

, giving most of the bitter taste to these crops. One eudesmanolide, 3-oxo-5αH,8βH-eudesma-1,4(15),7(11)-trien-8,12-olide, can work with

vernolic acid Vernolic acid (leukotoxin) is a long chain fatty acid that is monounsaturated and contains an epoxide. It is the R,R-''cis'' epoxide derived from the C12–C13 alkene of linoleic acid. Vernolic acid was first definitively characterized in 1954. I ...

and other compounds in plants to reduce inflammation.

Sesquiterpene lactone-containing plants

Some plants containing these compounds include: *

Artichoke The globe artichoke ('' Cynara cardunculus'' var. ''scolymus'' ),Rottenberg, A., and D. Zohary, 1996: "The wild ancestry of the cultivated artichoke." Genet. Res. Crop Evol. 43, 53–58. also known by the names French artichoke and green artich ...

*Boneset Eupatorium perfoliatum * Burdock *'' Calea ternifolia'' * Chamomile *''

Chrysanthemum Chrysanthemums (), sometimes called mums or chrysanths, are flowering plants of the genus ''Chrysanthemum'' in the family Asteraceae. They are native to East Asia and northeastern Europe. Most species originate from East Asia and the center ...

'' * Cocklebur * Feverfew *'' Gaillardia'' *''

Ginkgo biloba ''Ginkgo biloba'', commonly known as ginkgo or gingko ( ), also known as the maidenhair tree, is a species of tree native to China. It is the last living species in the order Ginkgoales, which first appeared over 290 million years ago. Fossils ...

'' *''

Laurus nobilis ''Laurus nobilis'' is an aromatic evergreen tree or large shrub with green, glabrous (smooth) leaves. It is in the flowering plant family Lauraceae. It is native to the Mediterranean region and is used as bay leaf for seasoning in cookin ...

'' *

Lettuce Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of foo ...

('' Lactuca'') *

Marsh elder ''Iva'' is a genus of wind-pollinated plants in the family Asteraceae, described as a genus by Linnaeus in 1753. Plants of this genus are known generally as marsh elders. The genus is native to North America. ; Accepted species * ''Iva angustifo ...

Mugwort Mugwort is a common name for several species of aromatic flowering plants in the genus ''Artemisia.'' In Europe, mugwort most often refers to the species ''Artemisia vulgaris'', or common mugwort. In East Asia the species ''Artemisia argyi'' is ...

*'' Parthenium'' * Poverty weed * Pyrethrum * Ragweed *

Sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus '' Artemisia''. The best known sagebrush is the shrub '' Artemisia tridentata''. Sagebrushes are native to the North American west. Following is an al ...

* Sneezeweed *

Spinach Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to central and western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common edible vegetable consumed eith ...

* Star anise * Sunflower * Ironweed *

Wormwood Wormwood may refer to: Biology * Several plants of the genus ''Artemisia'': ** ''Artemisia abrotanum'', southern wormwood ** '' Artemisia absinthium'', common wormwood, grande wormwood or absinthe wormwood ** ''Artemisia annua'', sweet wormwood o ...

Yellow star thistle ''Centaurea solstitialis'', the yellow star-thistle, is a species of thorny plant in the genus '' Centaurea'', which is part of the family Asteraceae. A winter annual, it is native to the Mediterranean Basin region and invasive in many other p ...

* bitter leaf Quorum sensing inhibitors Sesquiterpene lactones have been found to possess the ability to inhibit quorum sensing in bacteria.

References

External links

* {{Commons category-inline, Sesquiterpene lactones