Isolation and identification of a new hypocrellin A-producing strain Shiraia sp. SUPER-H168.

A new hypocrellin A-producing strain, Shiraia sp. SUPER-H168, was isolated from tissues of bamboo, Brachystachyum densiflorum. The morphology of this strain was characterized with a light microscope and a scanning electronic microscope. The mycelia, conidia, pycnidia of fungus were observed. Small pycnidia (10-20 microm in length) full of small conidia appeared on the mycelia, which were first reported in this study. The 18S rDNA region of this strain was amplified and sequenced. Then a neighbor-joining tree of 18S rDNA was constructed. According to the result of analysis, the strain SUPER-H168 was proved to belong to the genus Shiraia. Hypocrellin A was produced by solid-state fermentation, extracted by acetone, isolated by preparative RP-HPLC, and identified by RP-HPLC, ESI-MS and ultraviolet-visible absorbing scanning with diode array detection. The HA production could reach 2.02 mg/g dry solid substrate.