Antibacterial activity of the endophytic fungi from a traditional Chinese herb Paris polyphylla var. chinensis

Abstract

A total of 29 endophytic fungal isolates were separated from the healthy rhizomes of Paris polyphylla var. chinensis (Trilliaceae), which is a traditional medicinal herb mainly distributed in central China. Eight distinct isolates (that is, Papochf01-Papochf08) were selected for further taxonomical identification by morphological traits and internal transcribed spacer (ITS) rRNA gene sequence analysis. The results based on morphological characters revealed six genera namely Bionectria (Papochf04), Fusarium(Papochf05), Leptodontidium (Papochf07), Neonectria (Papochf02), Setophoma(Papochf08) and Trichocladium (Papochf01). Isolates Papochf01, Papochf02, Papochf03, Papochf06 and Papochf08 have not been previously reported as the endophytic fungi. The filtrate and mycelia n-butanol extracts obtained from the isolates Papochf05 and Papochf08 exhibited strong inhibition on all the test bacteria including Agrobacterium tumefaciens, Bacillus subtilis, Escherichia coli, Pseudomonas lachrymans,Staphylococcus aureus, Staphylococcus haemolyticus, Salmonella typhimurium, andXanthomonas vesicatoria. This finding shows that endophytic fungi from P. polyphylla var.chinensis could be an alternative source for producing antimicrobial agents. Key words: Paris polyphylla var. chinensis, endophytic fungi, n-butanol extract, TLC-bioautography assay, antibacterial activity