Helenin is a

phytochemical Phytochemicals are chemical compounds produced by plants, generally to help them resist fungi, bacteria and plant virus infections, and also consumption by insects and other animals. The name comes . Some phytochemicals have been used as poisons ...

mixture found in many plant species, including the '' Inula helenium'' (elecampane) 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 w ...

. It is a mixture of two

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

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

s, alantolactone and isoalantolactone. In 1895 the German scientists Julius Bredt and Wilhelm Posh extracted helenin from ''Inula helenium'' and determined its physical and chemical properties.

Natural sources

Alantolactone occurs in the roots of ''Inula helenium'' and other '' Inula'' species.

Properties

Helenin can be extracted from the roots of ''Inula helenium'' using alcohol or other non-polar solvents to produce a mixture with a composition of about 40% alantolactone and 60% isoalantolactone.

Biological activity

Alantolactone has a variety of ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

'' biochemical properties, including: * induces

apoptosis Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death. These changes incl ...

and

cell cycle The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells. These events include the duplication of its DNA (DNA replication) and some of its organelles, and subs ...

arrest in lung squamous cancer cells * suppresses STAT3 activation * has antiinflammatory effects by inhibiting

chemokine Chemokines (), or chemotactic cytokines, are a family of small cytokines or signaling proteins secreted by cells that induce directional movement of leukocytes, as well as other cell types, including endothelial and epithelial cells. In additio ...

production and STAT1

phosphorylation In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, wh ...

* anti-fungal * anti-microbial

Toxicity

Certain individuals have experienced contact dermatitis when exposed to alantolactone.

References

{{Reflist Sesquiterpene lactones Naphthofurans