FR198248, a new anti-influenza agent isolated from Apsergillus terreus No 13830. I. Taxomony, fermentation, isolation, physico-chemical properties and biological activities

A novel anti-influenza agent, FR198248, was isolated from the cultured broth of a fungal strain No.13830. The strain was identified as Aspergillus terreus from morphological characteristics. FR198248, a new type of hydroxyl benzaldehyde compound, showed antiinfluenza virus activity in Madin-Darby canine kidney (MDCK) cells in vitro. The mode of action of FR198248 against influenza virus A could be ascribed to an inhibitory effect on the stage of virus adsorption. Furthermore, FR198248 possessed potent in vivo anti-influenza activity in a murine model of respiratory tract infection.