“…In many cases, antimicrobial effects of various plant extracts have been attributed to their flavonoid contents (Tsao et al, 1982;Cafarchia et al, 1999). Flavonoid derivatives have also been reported to possess antiviral activity against a wide range of viruses such as HSV, HIV, Coxsackie B virus, coronavirus, cytomegalovirus, poliomyelitis virus, rhinovirus, rotavirus, poliovirus, sindbis virus, and rabies virus (De Bruyne et al, 1999;Evers et al, 2005;Chávez et al, 2006;Nowakowska, 2007). In a study by Chiang et al (2002), Plantago major, which has been used in the treatment of viral hepatitis in Chinese traditional medicine, showed a strong anti-herpes activity against HSV-1 and antiviral activity of the aqueous extract of this species mainly attributed to its rich phenolic content, caffeic acid, in particular, which is consistent with our data (Table 1).…”