Onion

Onion:
Caution:
None
Part used: Fresh or a dried powdered and granulated bulb.

Therapeutic action:
Onion has been suggested to be effective in treating a broad range of disorders, including:
asthma,
inflammatory disorders,
dysentery,
wounds,
scars,
keloids and pain.

In addition, different studies have demonstrated that onion possesses numerous pharma-cological properties, including:
anti-cancer,
anti-diabetic and anti-platelet properties as well as the effect on bone,
cardiovascular,
gastrointestinal,
nervous,
respiratory, and
urogenital systems effects such as anti-osteoporosis,
anti-hypertensive,
antispasmodic,
anti-diarrheal,
neuro-protective,
anti-asthmatic
and diuretic effects.

Discription:
Additional article information

Abstract Onion or Allium cepa (A. cepa) is one of the most important condiment plants grown and consumed all over the world. This plant has various therapeutic effects attributed to its constituents, such as quercetin, thiosulphinates and phenolic acids. In the present article, various pharmacological and therapeutic effects of A. cepa were reviewed. Different online databases using keywords such as onion, A. cepa, therapeutic effects, and pharmacological effects until the end of December 2019 were searched for this purpose.

The present review provides detailed the various pharma-cological properties of onion and its constituents and possible underlying mechanisms. The results of multiple studies suggested the therapeutic effect of onion on a wide range of disorders.

Introduction
Allium cepa (A. cepa) is a bulbous perennial or biennial monocot plant belonging to the family Liliaceae and the genus Allium, which includes over 250 genera and 3700 species (1-4). It is believed that the origin of A. cepa is central Asia, possibly the regions of Iran and Pakistan. However, it has now been distributed all over the world, such as Europe, North America and Africa (2, 5). A. cepa has several vernacular names like Onion in English, Cyvannulli in Malayalam, Pyaj in Hindi, Miruli in Kannada and Piaz in Farsi. The flowers of onion are small and usually purple or white. The root system of this plant is superficial and the stem at its base is very short flattened which increases in diameter as growth continues. The leaves of onion are long, linear, hollow and cylindrical. When the plant reaches a certain stage of growth, the leaf bases become thick and form a bulb (5). Onion is categorized based on their color into yellow, red and white and based on their taste as sweet and non-sweet (6, 7). This plant is used in many forms, including raw bulbs, fresh juice, fried and roasted (8-11).

Medicinal uses:
Onion has been known that possesses various medicinal properties from ancient times (12). The plant is traditionally used to treat different diseases such as cough due to bronchitis,
asthma,
inflammatory disorders,
dysentery,
ulcer wounds,
scars,
keloids,
pain and swelling after bee or wasp stings (13).

Experimental researches have also shown numerous pharmacological effects for onion, including: decreases blood levels of cholesterol,
triglycerides and thromboxanes (substances involved in the development of cardiovascular disease),
inhibits platelet aggregation and platelet-mediated thrombosis (a process resulting in heart attacks and strokes),
functions as a hypogly neuroprotective,
anti-convulsant,
anti-hypertensive,
anti-depressant and diuretic agent,
as well as the release of histamine associated with asthma,
stimulates the immune system and decreases osteoporosis (14-32). Moreover,
onion is one of the strongest anti-carcinogenic components because it suppresses the growth of carcinogenic cells (33).

This article reviews the pharmacological properties of onion and its constituents along with possible mechanisms in various fields.

Iranian Journal of
Pharmaceutical Research:
IJPR. - Brieflands."

Master Herbalist.