Isolation, antibacterial activity, and molecular identification of endophytic fungi from Pogostemon cablin

Abstract

Pogostemon cablin is the medicinal plants that produces patchouli essential oils as secondary metabolites which has multiple functions including antibacterial ability. The secondary metabolites in plants mostly associated with their endophytic fungi. In this study we isolated endophytic fungi from Pogostemon cablin’s leaves and examined antibacterial activity of the endophytic fungi against Escherichia coli and Staphylococcus aureus, as well as find out the identity of most potential isolate based on Internal Transcribe Spacer (ITS) region. The isolation of endophytic fungi was performed using surface sterilization method on Malt Extract Agar (MEA) medium. The antibacterial activity was tested using paper disc on Muller Hinton Agar (MHA) medium and molecular identification was amplified using ITS 4 and ITS 5 primers. The isolation process resulted in 5 isolates of endophytic fungi. The antibacterial assay indicated one potential isolate with the highest antibacterial activity when tested against E. coli and S. Aureus, exhibited 20.9 mm and 19 mm clear zone respectively. Molecular identification from ITS region database depicted that the potential isolate has high homology with Nigrospora sp. by 99% similarity. This result suggested that the antibacterial ability of essential oils from the Pogostemon cablin’s leaves might has high correlation with the occurrence of endophytic fungi.