Antifungal activity of plant extracts against Arthrinium sacchari and Chaetomium funicola

Various plant extracts were examined for antifungal activity with the objec tive of improving the commercial sterility of aseptically filled tea bevera ge products in PET bottles. When the hot water extract and the methanol ext ract of 29 samples were measured for their antifungal activity against Arth rinium sacchari M001 and Chaetomium funicola M002 strains, five samples, Ac er nikoense, Glycyrrhiza glabra, Lagerstroemia speciosa, Psidium guajava an d Thea sinensis, showed high activity. Of these, the extracts from A. nikoe nse, G. glabra and T. sinensis were fractionated by extraction with CHCl3, and the CHCl3-soluble fractions from G. glabra showed antifungal activity w ith minimum inhibitory concentrations (MICs) between 62.5 and 125 mug/ml ag ainst the above-mentioned two fungi. When the EtOAc-soluble fraction of A. nikoense was used, the MIC against A. sacchari M001 was 62.5 mug/ml. Howeve r, none of the fractions from A. nikoense or T. sinensis showed high activi ty against C. funicola M002 and their MICs were greater than 500 mug/ml. A licorice preparation made from the commercially available oh-based extract of G. glabra showed a low MIC of 25 mug/ml against five tested strains of f ilamentous fungi, but not against Aspergillus fumigatus M008, in a blended tea. Consequently, the possibility of adding a licorice preparation made fr om the oh-based extract of G. glabra to tea beverages (aseptically filled i nto PET bottles) was suggested.