Sesquiterpene lactones (SLs) are a class of sesquiterpenoids that contain a lactone ring. They are most often found in plants of the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

(daisies, asters). Other plant families with SLs are Umbelliferae (celery, parsley, carrots) and

Magnoliaceae The Magnoliaceae () are a flowering plant family, the magnolia family, in the order Magnoliales. It consists of two genera: '' Magnolia'' and ''Liriodendron'' (tulip trees). Unlike most angiosperms, whose flower parts are in whorls (rings), ...

(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 Neurology (from , "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the nervous system, which comprises the brain, the s ...

problems in horses. Some are also found in corals of the order '' Alcyonacea''.

Types

Sesquiterpene lactones can be divided into several main classes including germacranolides, heliangolides, guaianolides, pseudoguaianolides, hypocretenolides, and eudesmanolides.

Examples

Artemisinin, a new, highly-effective anti-

malaria Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...

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 is also found in dandelion coffee. It has b ...

, desoxylactucin,

lactucopicrin Lactucopicrin (Intybin) is a bitter substance that has a sedative and analgesic effect, acting on the central nervous system. It is a sesquiterpene lactone, and is a component of lactucarium, derived from the plant ''Lactuca virosa'' (wild lettu ...

, 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 mostly grown as a leaf vegetable. The leaves are most often used raw in Green salad, green salads, although lettuce is also seen in other kinds of food, such as sandwiche ...

and

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

, 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 B or isoleukotoxin) is a long chain fatty acid that is monounsaturated and contains an epoxide. It is a ''cis'' epoxide derived from the C12–C13 alkene of linoleic acid. Vernolic acid was first definitively character ...

and other compounds in plants to reduce inflammation.

Sesquiterpene lactone-containing plants

Some plants containing these compounds include: * Artichoke *'' Eupatorium'' * Burdock *'' Calea ternifolia'' *

Chamomile Chamomile (American English) or camomile (British English; see spelling differences) ( or ) is the common name for several plants of the family Asteraceae. Two of the species, '' Matricaria chamomilla'' and '' Chamaemelum nobile'', are commo ...

*''

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

'' *'' Dandelion'' (Taraxacum sp.) * Cocklebur * Feverfew *'' Gaillardia'' *''

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

'' *'' Laurus nobilis'' *

Lettuce Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae mostly grown as a leaf vegetable. The leaves are most often used raw in Green salad, green salads, although lettuce is also seen in other kinds of food, such as sandwiche ...

('' Lactuca'') * Mugwort *'' Parthenium'' *'' Iva'' (marsh elders) * Pyrethrum * Ragweed *

Sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus ''Artemisia (plant), Artemisia''. The best-known sagebrush is the shrub ''Artemisia tridentata''. Sagebrush is native to the western half of North Amer ...

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

Star anise ''Illicium verum'' (star anise or badian, Chinese star anise, star anise seed, star aniseed and star of anise) is a medium-sized evergreen tree native to South China and northeast Vietnam. Its star-shaped pericarps harvested just before ripen ...

Sunflower The common sunflower (''Helianthus annuus'') is a species of large annual forb of the daisy family Asteraceae. The common sunflower is harvested for its edible oily seeds, which are often eaten as a snack food. They are also used in the pr ...

*'' Vernonia'' * Wormwood * Yellow star thistle 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