Environmental differences between Japan and Indonesia provide endophyte diversity associated with Artemisia plant and variety of artemisinin derivatives in microbial conversion.

We compared the endophytic compositions of Artemisia plant from different environments (Japan and Indonesia) to demonstrate that the endophytic filamentous fungi in both species differed based on their environments. To prove that the species were identical, both Artemisia plants were identified by comparing the scanning electron micrographs of their pollens, as well as the nucleotide sequences (ribosomal internal transcribed spacer and mitochondrial maturase K) of the two gene regions. After isolating the endophytic filamentous fungi from each plant, we observed that those from Japan and Indonesia comprised 14 and 6 genera, respectively. We assumed that the genera, Arthrinium and Colletotrichum, which exist in both Artemisia species, were species-specific filamentous fungi, while the other genera were environment-dependent. In the microbial-conversion reaction with artemisinin as a substrate using Colletotrichum sp., the peroxy bridge of artemisinin, which is an active site for achieving antimalarial effect, was converted into an ether bond. However, the reaction using the environment-dependent endophyte did not eliminate the peroxy bridge. These endophytic reactions indicated the different roles of endophytes within Artemisia plants.