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http://dx.doi.org/10.4014/jmb.1105.05016

Poly(L-Lactide)-Degrading Enzyme Production by Actinomadura keratinilytica T16-1 in 3 L Airlift Bioreactor and Its Degradation Ability for Biological Recycle  

Sukkhum, Sukhumaporn (Faculty of Science, Srinakharinwirot University)
Tokuyama, Shinji (Faculty of Agriculture, Shizuoka University)
Kitpreechavanich, Vichien (Faculty of Science, Kasetsart University)
Publication Information
Journal of Microbiology and Biotechnology / v.22, no.1, 2012 , pp. 92-99 More about this Journal
Abstract
The optimal physical factors affecting enzyme production in an airlift fermenter have not been studied so far. Therefore, the physical parameters such as aeration rate, pH, and temperature affecting PLA-degrading enzyme production by Actinomadura keratinilytica strain T16-1 in a 3 l airlift fermenter were investigated. The response surface methodology (RSM) was used to optimize PLA-degrading enzyme production by implementing the central composite design. The optimal conditions for higher production of PLA-degrading enzyme were aeration rate of 0.43 vvm, pH of 6.85, and temperature at $46^{\circ}C$. Under these conditions, the model predicted a PLA-degrading activity of 254 U/ml. Verification of the optimization showed that PLA-degrading enzyme production of 257 U/ml was observed after 3 days cultivation under the optimal conditions in a 3 l airlift fermenter. The production under the optimized condition in the airlift fermenter was higher than un-optimized condition by 1.7 folds and 12 folds with un-optimized medium or condition in shake flasks. This is the first report on the optimization of environmental conditions for improvement of PLA-degrading enzyme production in a 3 l airlift fermenter by using a statistical analysis method. Moreover, the crude PLA-degrading enzyme could be adsorbed to the substrate and degraded PLA powder to produce lactic acid as degradation products. Therefore, this incident indicates that PLA-degrading enzyme produced by Actinomadura keratinilytica NBRC 104111 strain T16-1 has a potential to degrade PLA to lactic acid as a monomer and can be used for the recycle of PLA polymer.
Keywords
Actinomadura keratinilytica; airlift fermenter; biodegradation; central composite design; PLA-degrading enzyme;
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1 Sukkhum, S., S. Tokuyama, T. Tamura, and V. Kitpreechavanich. 2009. A novel poly(L-lactide) degrading actinomycetes isolated from Thai forest soils, phylogenic relationship and enzyme characterization. J. Gen. Appl. Microbiol. 55: 459-467.   DOI
2 Sukkhum, S., S. Tokuyama, and V. Kitpreechavanich. 2009. Development of fermentation process for PLA-degrading enzyme production by a new thermophilic Actinomadura sp. T16-1. Biotechnol. Bioprocess Eng. 14: 302-306.   DOI
3 Tanyildizi, M. S., D. Ozer, and M. Elibol. 2005. Optimization of $\alpha$-amylase production by Bacillus sp. using RSM. Process Biochem. 40: 2291-2296.   DOI
4 Tomita, K., Y. Kuroki, and K. Nakai. 1999. Isolation of thermophiles degrading poly(L-lactic acid). J. Biosci. Bioeng. 87: 752-755.   DOI
5 Tomita, K., T. Nakajima, Y. Kikuchi, and N. Miwa. 2004. Degradation of poly(L-lactic acid) by a newly isolated thermophile. Polym. Degrad. Stab. 84: 433-438.   DOI
6 Tsuji, H. and K. Nakahara. 2002. Poly(L-lactide) IX. Hydrolysis in acid media. J. Appl. Polym. Sci. 86: 186-194.   DOI
7 Anbu, P., S. C. B. Gopinath, A. Hilda, T. Lakshmipriya, and G. Annadurai. 2007. Optimization of extracellular keratinase production by poultry farm isolate Scopulariopsis brevicaulis. Bioresour. Technol. 98: 1298-1303.   DOI
8 Box, G. E. P. and K. B. Wilson. 1951. On the experimental attainment of optimum conditions. J. Roy. Stat. Soc. B 13: 1-45.
9 Jarerat, A. and Y. Tokiwa. 2001. Degradation of poly(L-lactide) by a fungus. Macromol. Biosci. 1: 136-140.   DOI
10 Jarerat, A., Y. Tokiwa, and H. Tanaka. 2004. Microbial poly(Llactide)- degrading enzyme induced by amino acids, peptides, and poly(L-amino acids). J. Polym. Eviron. 12: 139-146.   DOI
11 Jarerat, A., Y. Tokiwa, and H. Tanaka. 2006. Production of poly(L-lactide)-degrading enzyme by Amycolatopsis orientalis for biological recycling of poly(L-lactide). Appl. Microbiol. Biotechnol. 72: 726-731.   DOI
12 Kim, M. N., W. G. Kim, H. Y. Weon, and S. H. Lee. 2007. Poly(L-lactide)-degrading activity of a newly isolated bacterium. J. Appl. Polym. Sci. 109: 234-239.
13 Li, Y., F. Cui, Z. Liu, Y. Xu, and H. Zhao. 2007. Improvement of xylanase production by Penicillium oxalicum ZH-30 using response surface methodology. Enzyme Microb. Technol 40: 1381-1388.   DOI
14 Myers, R. H. and D. C. Montgomery. 2002. Response Surface Methodology: Process and Product Optimization Using Designed Experiments, 2nd Ed. John Wiley and Sons, Inc.
15 Naidu, K. S. B. and K. L. Devi. 2005. Optimization of thermostable alkaline protease production from species of Bacillus using rice bran. Afr. J. Biotechnol. 4: 724-726.   DOI
16 Qadar, S. A. U., E. Shireen, S. Iqbal, and A. Anwar. 2009. Optimization of protease production from newly isolated strain of Bacillus sp. PCSIR EA-3. Indian J. Biotechnol. 8: 286-290.
17 Sakai, K., H. Kawano, A. Iwami, M. Nakamura, and M. Moriguchi. 2001. Isolation of a thermophilic poly-L-lactide degrading bacterium from compost and its enzymatic characterization. J. Biosci. Bioeng. 92: 298-300.   DOI
18 Singh, R. S., B. S. Sooch, and M. Puri. 2007. Optimization of medium and process parameters for the production of inulinase from a newly isolated Kluyveromyces marxianus YS-1. Bioresour. Technol. 98: 2518-2525.   DOI