Characterization and induction of phenolic acid decarboxylase from Aspergillus luchuensis.

Awamori is a traditional distilled liquor in the Ryukyu Islands, made from steamed rice by the action of the black-koji mold Aspergillus luchuensis and awamori yeast Saccharomyces cerevisiae. One of the specific flavors in aged awamori kusu is vanillin, which is derived from ferulic acid (FA) in rice grains. FA is released from the cell wall material in the rice grain by ferulic acid esterase produced by A. luchuensis. Through decarboxylation of FA, 4-vinylguaiacol (4-VG) is produced, which is transferred to the distilled liquor, and converted to vanillin by natural oxidization during the aging process. However, the actual mechanism for conversion of FA to 4-VG in the awamori brewing process is unknown. A genetic sequence having homology to the phenolic acid decarboxylase (PAD)-encoding region from bacteria and the yeast Candida guilliermondii has been identified in A. luchuensis mut. kawachii. In the present study, recombinant PAD from A. luchuensis, designated as AlPAD, expressed as a homodimer, catalyzed the conversion of FA to 4-VG, displayed optimal catalytic activity at pH 5.7 and 40°C, and was stable up to 50°C. Both rice bran and FA could induce the bioconversion of FA to 4-VG and the expression of AlPAD in A. luchuensis. The amount of AlPAD determined using western blotting correlated with the level of FA decarboxylase activity during koji production. In awamori brewing process, AlPAD might be responsible for a part of the conversion of FA to 4-VG.

Successful treatment of adult-type granulosa cell tumor of the ovary by palliative radiotherapy.

A 76-year-old woman underwent laparotomy at another hospital because of acute abdomen. Owing to strong attachment and dissemination of the tumor, it was unresectable. Adult-type granulosa cell tumor (AGCT) was diagnosed based on pathological examination. Considering her poor condition, she was advised to receive total supportive care. However, she was lost to follow-up after a few months. Subsequently, she visited our hospital with abdominal distension. A large abdominal tumor and liver metastasis was observed on abdominal computed tomography (CT). We selected palliative radiotherapy to relieve her of the symptoms. External beam radiotherapy was delivered to the affected data. No acute adverse effects were observed. We observed reduction in tumor size on postoperative abdominal CT. She is still alive with no signs of tumor progression for 30 months. Palliative radiotherapy is effective for patients with advanced-stage AGCT and abdominal complaints.