1. Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic.
2. Fermentation Biotechnology Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, Peoria, IL 61604. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable.
3. Current address: Wyatt Technology Corp., Santa Barbara, CA 93117.
4. Corresponding author. Phone: 309-681-6377. Fax: 309-681-6427. E-mail: leathetd@ncaur.usda.gov.
5. Office of International Programs, Agricultural Research Service, USDA, Beltsville, MD 20705.