title: The structure, occurrence and biological activity of ellagitannins: a general review.
abstract: The present paper deals with the structure, occurrence and biological activity of ellagitannins. Ellagitannins belong to the class of hydrolysable tannins, they are esters of hexahydroxydiphenoic acid and monosaccharide (most commonly glucose). Ellagitannins are slowly hydrolysed in the digestive tract, releasing the ellagic acid molecule. Their chemical structure determines physical and chemical properties and biological activity. Ellagitannins occur naturally in some fruits (pomegranate, strawberry, blackberry, raspberry), nuts (walnuts, almonds), and seeds. They form a diverse group of bioactive polyphenols with anti-inflammatory, anticancer, antioxidant and antimicrobial (antibacterial, antifungal and antiviral) activity. Furthermore, they improve the health of blood vessels. The paper discusses the metabolism and bioavailability of ellagitannins and ellagic acid. Ellagitannins are metabolized in the gastrointestinal tract by intestinal microbiota. They are stable in the stomach and undergo neither hydrolysis to free ellagic acid nor degradation. In turn, ellagic acid can be absorbed in the stomach. This paper shows the role of cancer cell lines in the studies of ellagitannins and ellagic acid metabolism. The biological activity of these compounds is broad and thus the focus is on their antimicrobial, anti-inflammatory and antitumor properties. Ellagitannins exhibit antimicrobial activity against fungi, viruses, and importantly, bacteria, including antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus.
authors.affiliation: Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Poland.
authors.forename: Lidia
authors.initials: L
authors.lastname: Lipińska
authors.affiliation: Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Poland Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Klewicka
authors.affiliation: Institute of Chemical Technology of Food, LoLodz University of Technology, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Sójka
mesh_terms: D000890:Anti-Infective Agents / Q000378:metabolism; D000893:Anti-Inflammatory Agents / Q000378:metabolism; D000970:Antineoplastic Agents / Q000378:metabolism; D004610:Ellagic Acid / Q000737:chemistry / Q000378:metabolism; D005638:Fruit / Q000737:chemistry; D041981:Gastrointestinal Tract / Q000378:metabolism; D006801:Humans; D047348:Hydrolyzable Tannins / Q000737:chemistry / Q000378:metabolism; D009754:Nuts / Q000737:chemistry; D059808:Polyphenols / Q000737:chemistry / Q000378:metabolism
chemical_list: D000890:Anti-Infective Agents; D000893:Anti-Inflammatory Agents; D000970:Antineoplastic Agents; D047348:Hydrolyzable Tannins; D059808:Polyphenols; D004610:Ellagic Acid