Antimicrobial activity of flavonoids

• Published in: International journal of antimicrobial agents Vol. 26; no. 5; pp. 343 - 356
• Main Authors: Cushnie, T.P. Tim, Lamb, Andrew J.
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 01.11.2005; Amsterdam Elsevier; New York, NY Elsevier B.V. and the International Society of Chemotherapy
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; Anti-Infective Agents - chemistry; Anti-Infective Agents - pharmacology; Antibacterial; Antibiotics. Antiinfectious agents. Antiparasitic agents; Antifungal; Antifungal Agents - chemistry; Antifungal Agents - pharmacology; Antiviral; Antiviral Agents - chemistry; Antiviral Agents - pharmacology; Bacteriology; Biochemistry; Biochemistry, Molecular Biology; Biological and medical sciences; Biotechnology; Chemical Sciences; Energy Metabolism - drug effects; Flavonoids; Flavonoids - chemistry; Flavonoids - pharmacology; Human health and pathology; Humans; Infectious diseases; Life Sciences; Mechanism of action; Medical sciences; Medicinal Chemistry; Microbiology and Parasitology; Mycology; Nucleic Acid Synthesis Inhibitors - chemistry; Nucleic Acid Synthesis Inhibitors - pharmacology; Organic chemistry; Pharmaceutical sciences; Pharmacology; Pharmacology. Drug treatments; Quantitative Methods; Review; Structure-Activity Relationship; Structure–activity; Terminology as Topic; Toxicology; Virology; Structure–activity; Antiviral; Flavonoids; Antifungal; Antibacterial; Mechanism of action; Antifungal: Antiviral; Flavonoid; Biological activity; Antimicrobial agent; Polyphenol; Antifungal agent; Structure-activity; Structure activity relation; Phenols; Antibacterial agent
• ISSN: 0924-8579; 1872-7913; 0924-8579
• DOI: 10.1016/j.ijantimicag.2005.09.002

Flavonoids are ubiquitous in photosynthesising cells and are commonly found in fruit, vegetables, nuts, seeds, stems, flowers, tea, wine, propolis and honey. For centuries, preparations containing these compounds as the principal physiologically active constituents have been used to treat human diseases. Increasingly, this class of natural products is becoming the subject of anti-infective research, and many groups have isolated and identified the structures of flavonoids possessing antifungal, antiviral and antibacterial activity. Moreover, several groups have demonstrated synergy between active flavonoids as well as between flavonoids and existing chemotherapeutics. Reports of activity in the field of antibacterial flavonoid research are widely conflicting, probably owing to inter- and intra-assay variation in susceptibility testing. However, several high-quality investigations have examined the relationship between flavonoid structure and antibacterial activity and these are in close agreement. In addition, numerous research groups have sought to elucidate the antibacterial mechanisms of action of selected flavonoids. The activity of quercetin, for example, has been at least partially attributed to inhibition of DNA gyrase. It has also been proposed that sophoraflavone G and (−)-epigallocatechin gallate inhibit cytoplasmic membrane function, and that licochalcones A and C inhibit energy metabolism. Other flavonoids whose mechanisms of action have been investigated include robinetin, myricetin, apigenin, rutin, galangin, 2,4,2′-trihydroxy-5′-methylchalcone and lonchocarpol A. These compounds represent novel leads, and future studies may allow the development of a pharmacologically acceptable antimicrobial agent or class of agents.