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United States Department of Agriculture

Agricultural Research Service

Research Project: NOVEL TECHNOLOGIES FOR PRODUCING RENEWABLE CHEMICALS AND POLYMERS FROM CARBOHYDRATES DERIVED FROM AGRICULTURAL FEEDSTOCKS

Location: Renewable Product Technology Research Unit

Title: Poly (beta-L-malic acid) production by diverse phylogenetic clades of Aureobasidium pullulans

Authors
item Manitchotpisit, Pennapa -
item Skory, Christopher
item Peterson, Stephen
item Price, Neil
item Vermillion, Karl
item Leathers, Timothy

Submitted to: Journal of Industrial Microbiology and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 6, 2011
Publication Date: July 1, 2011
Repository URL: http://handle.nal.usda.gov/10113/54004
Citation: Manitchotpisit, P., Skory, C.D., Peterson, S.W., Price, N.P., Vermillion, K., Leathers, T.D. 2012. Poly (beta-L-malic acid) production by diverse phylogenetic clades of Aureobasidium pullulans. Journal of Industrial Microbiology and Biotechnology. 39(1):125-132. DOI: 10.1007/s10295-011-1007-7.

Interpretive Summary: Improved microbial germplasm is needed to enhance bioconversions of agricultural materials to high-value bioproducts. Genetically diverse strains of an industrially important fungus were examined for the production of a natural biopolymer that may have applications in the production of detergents, biodegradable plastics, or other biomaterials. Several genetic groups were identified that produce this polymer. This work will be of interest to researchers developing new uses and value-added products from agricultural commodities and byproducts.

Technical Abstract: Poly (beta-L-malic acid) (PMA) is a natural biopolyester that has pharmaceutical applications and other potential uses. Here we examine PMA production by genetically diverse phylogenetic clades of the fungus A. pullulans. Thirty-six strains of A. pullulans were isolated for this study from various locations in Iceland and Thailand. All strains from Iceland belonged to a newly recognized clade 13, while strains from Thailand were distributed among 8 other clades, including a novel clade 14. Thirty of these isolates and 26 previously described strains were examined for PMA production in medium containing 5% glucose. Most strains produced at least 4 g PMA/L, and several strains in clades 9, 11, and 13 made 9-11 g PMA/L. Strains also produced both pullulan and heavy oil, but PMA isolated by differential precipitation in ethanol exhibited up to 72% purity with no more than 12% contamination by pullulan. The molecular weight of PMA from A. pullulans ranged from 6.4 to 7.9 kDa.

Last Modified: 12/20/2014