Anthocyanins: Chemistry and biological activity ; Antocijani - hemijska analiza i biološka aktivnost

Anthocyanins are a group of over 500 different compounds that cause red, purple and blue colours of many plants, especially fruits, vegetables and cereals. Anthocyanins structurally belong to flavones. Mainly fruit is considered the main source of anthocyanins, although they are present in vegetables, roots, bulbs, fruit pulps, pulses and cereals. Huge diversity of anthocyanins, which can be found in nature makes them very complex and interesting group. In plants anthocyanins are present in the form of heterosides. Aglycone anthocyanins are known as anthocyanins. In nature there is 6 well known anthocyanins: pelargonidin, cyanidin, peonidin, delphinidin, malvidin and petunidin. Pelargonidin as stable anthocyanins is the most frequent in nature. The glycoside derivatives of the most widespread in nature are 3-monoside, 3.5 and 3.7 biosides. Interest for anthocyanins is growing over the past few years due to their potential applications in the pharmaceutical industry, the food and cosmetic industries. Despite their great potential, their use is still limited because of their relative instability and the low percentage of extracting from the plant material. Anthocyanins are quite reactive and unstable compounds. They transform reversibly with pH changes. pH is defined as the greatest cause of instability of anthocyanins, and has the greatest impact on colour. Anthocyanins are polar molecules and the most efficient solvent for extraction are the mixture of polar solvent such as ethanol, methanol and acetone. Extraction methods for anthocyanins isolation are not selective because solvents extracted anthocyanins with ballast and the great number of substances such as sugars and organic acids. Because of that, it is necessary to implement a new purification techniques, such as solid phase extraction (SPE), liquid-liquid extraction (LLE), countercurrent chromatography (CCC), and high performance liquid chromatography (HPLC). Identification of anthocyanins play a key role in the taxonomy and evaluate the quality of ...