Centaurea is a large genus belonging to the sunflower family (Asteraceae). This is one of the largest plant families with 1000 genera and 15000 species. The Centaurea genus in particular comprises 400-700 species, is distributed all over the world, and is used in folk-medicine for its therapeutic and curative properties. They are native to Eurasia and their appearance in North America dates back to the late 1800’s and early 1900’s.

Centaurea extracts have been used for their effects as stimulants, diuretics, anti- rheumatics, anti-microbial, anti-inflammatory, anti-tumor and anti-diabetics. This has led scientists to investigate their efficacy in the lab. Many species have been the subject of extensive chemical investigations, with each country taking an interest in its own Centaurea; particularly those in South America, Europe and the Mediterranean.

One of the interesting Centaurea species that was extensively researched by IBSAR members at the AUB is Centaurea ainetensis. This species is endemic to Lebanon. It can only be found growing wild in particular areas in Lebanon. The stem is short and erect. It is 1-2 headed with the heads being small, oblong, rounded at the base, and not truncated. It grows in stony, sterile, or bushy places, but not in rocky habitats. It flowers from May to June.

The biological activities of this plant are attributed to a type of Sesquiterpene Lactone molecule known as Salograviolide A. It was found to exert a multitude of important biological activities confirming some of its uses in folkloric medicine.

Experiments on the crude extract and bioactive molecule in human and mouse cells have revealed promising anti-microbial, anti-inflammatory and anti-cancer properties of Centaurea ainetensis. The flower extract of this plant was shown to have about 90% anti-microbial efficacy against bacteria such as E. coli, Salmonella and Candida. The purified bioactive molecule exerts the same effect as the crude extract at much lower concentrations, proving the attribution of these biological effects to the isolated molecule; Salograviolide A. In a manner similar to that typically targeted by anti-inflammatory drugs on the market, Salograviolide A reverses the inflammatory process in an animal model by reducing the levels of inflammatory secreted proteins.

Furthermore, Salograviolide A is interesting in that it can reprogram cancer cells by activating their death and/or cell cycle arrest signaling proteins. Doses as low as 3-16 micrograms (almost one grain of sand) inhibit the growth of leukemic, epidermal (including skin), epithelial and colon cancer cells, and reduces invasiveness by 50% due to complete inhibition of a factor normally secreted to stimulate tumor growth. Our most interesting finding is that Salograviolide A kills cancer cells at concentrations that are not toxic to normal cells.
 

Related Publications:

• Anti-colon cancer effects of Salograviolide A isolated from Centaurea ainetensis: View Abstract

• Anti-inflammatory bio-activities in water extract of Centaurea ainetensis: View Abstract

• Anti-inflammatory properties of Salograviolide A purified from Lebanese plant Centaurea ainetensis: View Abstract

• Anti-tumor activities of extracts from indigenous Lebanese plants using a murine in vitro model of squamous cell carcinogenesis: View Abstract

• Bio-guided fractionation, Isolation & structure identification of an anti-inflammatory guaianolids from Centaurea ainetensis: View Abstract

• Comparative Antitumor Effects of Extracts from Selected Indigenous Plants of Lebanon against Colon Cancer using in vitro and in vivo Models: View Abstract

• Extracts from indigenous Lebanese plants as a source of inhibitors of cancer metastasis:View Abstract

• Purified salograviolide A isolated from Centaurea ainetensis causes growth inhibition and apoptosis in neoplastic epidermal cells: View Abstract

• PCR Use in Epidemiological Study of Avian Mycoplasmosis and Control of Gumboro by Herbal Extracts: View Abstract

• Screening of selected indigenous plants of Lebanon for antimicrobial activity: View Abstract
  
  
• The way to a Natural Bioactive Compound Extracted from an Endemic Lebanese Plant: View Abstract