Antiviral activity, proanthocyanidins

Keywords Antibacterial activity Antimycotic activity Antiprotozoal activity Antiviral activity Cathechins Proanthocyanidins... 

Catechins and proanthocyanidins have a documented antiviral activity. Catechins from an extract of Cocos nucifera husk fibre exhibited a strong inhibitory activity against acyclovir-resistant herpes simplex virus type 1 (HSV-l-ACVr) [62]. The use of 10 to 20ngml of ECG and EGCG has been reported to cause 50% inhibition of human immunodeficiency virus reverse transcriptase [89], while Kara and Nakayama [90] reported that a patented chewing gum containing tea catechins is claimed to prevent viral infections against influenza and to inhibit dissemination of this virus. 

SAR studies were carried out by de Bruyne et al. [92] on a series of dimeric procyanidins, considered as model compounds for antiviral therapies. On the whole, proanthocyanidins containing EC dimers exhibited more pronounced activity against herpes simplex virus (HSV) and human immunodeficiency virus (HIV), while the presence of ortho-trihydroxyl groups in the B-ring appeared to be essential in all proanthocyanidins exhibiting anti-HSV effects. Galloylation and polymerization reinforced the antiviral activities markedly. 

Documented effects This species is used to treat infectious diseases, hemorrhagic diathesis, gastritis (particularly with low acidity), and is used as a tonic to treat the cardio-vascular system (Akopov 1990). An extract of the fruits has shown antiviral activity against herpes and influenza A and B viruses (Knox et al. 2001,2003 Suzutani et al. 2003). Proanthocyanidins isolated from the leaves exhibit anti-inflanunatory effects in rats (Garbacki et al. 2004). 

The proanthocyanidins are widely distributed in nature and often represent the active compounds of medicinal plants or plants showing human health beneficial effects. Reports of several in vitro assays demonstrate potentially significant antiviral, antibacterial, molluscicidal, enzyme-inhibiting, antioxidant, and radical-scavenging properties. " Their potential to interact with biological systems rests, at least in part, on the ability to form complexes with other biomolecules, thus emphasizing the necessity to accurately define... 

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