SPORE AND GEOSMIN PRODUCTION BY STREPTOMYCES-TENDAE ON SEVERAL MEDIA

Geosmin (1,10-trans-dimethyl-trans-9-decalol) is produced by several microbial taxa and can impart musty/earthy off-flavors to food, potable water, and aquaculture-raised fish. The bacterium Streptomyces tendae (ATCC 31160) was grown on Hickey-Tresner (HT), Streptomyces (STR), Actinomyces (ACT), and American Type Culture Collection sporulation agar (ATCC). The greatest fresh biomass occurred on ATCC and the least on HT media. Sporulation occurred on ATCC and HT but not on STR and ACT media. Cultures produced geosmin on each media. However, sporulating cultures contained more geosmin than nonsporulating cultures. Cultures grown on ACT medium did not produce geosmin prior to 48 h after inoculation, and neither basic, acidic, nor enzymatic hydrolysis released geosmin, indicating that changes in geosmin content were due to de novo biosynthesis rather than release of bound metabolite.