Polyphenolic compounds of xanthones

Xanthones, polyphenolic compounds, are one of the most important classes in natural products. About 200 xanthones have been discovered. They exhibit variety of pharmacological and health benefits, i.e., anti-obesity, antidiabetic, antioxidant, anti-Alzheimer, anti-inflammatory, and anticancer.

Xanthones are yellow pigments in flowers. Xanthones with the basic molecular formula C13H8O2 are flavonoids and are found in some fruit and bark of tree, but the highest concentration is found in the pericarp of the mangosteen fruit. Xanthones from mangosteen have been reported as antioxidant, antibacterial especially for Mycobacterium tuberculosis and anticancer.

Many are polyketide derived, although others are formed from combined shikimic acid pathways combined with acetate-malonate units.

Three units of malonate react with a hydroxybenzoic acid (C6-C1). Benzophenones may be converted by oxidative rings closure into xanthones.

Several xanthones that possess antidepressant activity inhibit monoamine oxidases. These compounds have in vitro cytotoxicity and in vivo antitumor activity. Xanthones kill microbes, improve depression, stimulate the production of urine and improve the function of the heart.

Xanthones isolated from natural sources are classified into six main groups, namely, simple xanthones, xanthone glycosides, prenylated xanthones, xanthonolignoids, bisxanthones, and miscellaneous xanthones.
Polyphenolic compounds of xanthones

Xanthones in mangosteen

Xanthones are natural polyphenols with the basic molecular formula C13H8O2 that are commonly found in lichens, fungi, and higher plants.

Xanthones can be found in higher plants that are used as food sources, for example, Garcinia mangostana L. (the queen of fruits, mangosteen), a tropical fruit with reddish-purple pericarp. Mangosteen is used as popular food in beverages and in other health products.

γ-Mangostin (γ-MG) is a xanthone derived from Garcinia mangostana, used in folk medicine for treatment of abdominal pain, diarrhea, dysentery, wound infections, and chronic ulcers. Mangosteen derived xanthones, viz., α- and β-mangostin predominantly found in roots, barks, edible fruits, and seeds.

At least 68 distinct xanthones have been identified in different parts of the G. mangostana plant with 50 being present in the fruit’s pericarp at higher concentrations than in the aril or edible portion of the fruit. The most abundant xanthones in the pericarp of mangosteen fruit are α- and γ-mangostin.

Xanthones from mangosteen have been reported as antioxidant, antibacterial especially for Mycobacterium tuberculosis and anticancer.
Xanthones in mangosteen

Antioxidants in mangosteen

The mangosteen is one of the world’s most delicious fruits. The mangosteen is an exotic fruit that comes from Asia. The fruit has many health benefits and has been nicknamed "the queen of fruits" due to its delicious taste.

Not content with its culinary virtues, many retailers are touting it as a ‘miracle fruit’, useful for treating major diseases including cancer, heart disease, stroke diabetes and arthritis and having antiviral, anti-aging, antihistamine, antibiotic and anti-inflammatory properties.

Mangosteen pericarp consists of an array of polyphenols including mostly xanthones and tannins which create astringency. Mangosteen contains an abundant amount of xanthones, which are very powerful antioxidants. There is a whole family of this antioxidant, and the most dynamic of these are found in the mangosteen. Xanthones are found in a few rain forest plants, but they are for the most part found in the mangosteen fruit, and over 40 have been identified.

The important xanthones in mangosteen are α-mangostin, β-mangostin, 3-isomangostin, 9-hydroxycalabaxanthone, gartanin and 8-desoxygartanin. These xanthones have been shown to have a variety of benefits, by supporting the immune system and are a natural antibiotic, antifungal, antiviral, antiallergic, and perhaps most importantly, anti-inflammatory.
Antioxidants in mangosteen

Xanthones in fruit

Xanthones are one of the biologically active compounds and are unique among the group of polyphenolic compounds. Xanthones are found mainly in the Gentianaceae and Guttiferae otherwise scattered sporadically throughout the plant kingdom as in the Moraceae and Polygalaceae.

Xanthones are a group of yellow pigments. One well-known member is mangiferin, which occurs as a glycoside in mangoes.

Mangosteen fruit is the richest known source of natural xanthone compounds, which have tremendous medicinal value. Fruit hulls contain five polyoxygenated xanthones, mangostin 4, B-mangostin, nor-mangostin, gartamin and 8-desoxy gartamin.

Xanthones are said to enhance the body’s immune system and also impart other human health benefits such as promoting healthy cardiovascular or respiratory systems, supporting cartilage and joint function. 

Xanthones are antioxidants being researched for their ability to improve immune systems and have anti-viral, antibacterial, and anti-fungal properties.

Xanthines have antioxidant properties and they do this by deactivating free radicals in the body. In this regard, they are said to be even more potent antioxidants than vitamin E and C.
Xanthones in fruit