Production of poly-?-glutamic acid by <i>Bacillus licheniformis</i>: Synthesis and characterization

Authors

  • Nuttawut Konglom Department of Biotechnology, Kasetsart University and Center for Advanced Studies in Tropical Natural Resources, National Research University-Kasetsart University
  • Chaniga Chuensangjun Department of Biotechnology, Kasetsart University
  • Chiravoot Pechyen Department of Packaging and Materials Technology, Kasetsart University and Center for Advanced Studies in Agriculture and Food, KU Institute for Advanced Studies, Kasetsart University
  • Sarote Sirisansaneeyakul Department of Biotechnology, Kasetsart University and Center for Advanced Studies in Tropical Natural Resources, National Research University-Kasetsart University

Keywords:

Poly-γ-glutamic acid, L-glutamic acid, Bacillus licheniformis, Bio-polymer

Abstract

Poly-?-glutamic acid (?-PGA), one type of amino acid polymers, consists of D-and L-glutamic acids linked with amide bonding between ?-amino and ?-carboxylic acids. Naturally, ?-PGA could be biodegradable polymer and water-solubleapplied in various industries such as food, cosmetics, and pharmaceutical industries. Variation of initial L-glutamic acid concentration affecting on the production of ?-PGA by fermentation of Bacillus licheniformis was studied. The batch fermentation process consists of preparing the inoculum and expanding the culture of B. licheniformis into E medium (pH 6.5) for ?-PGA production. ?-PGA was recovered by using methanol precipitation together with lyophilization. For characterization, the molecular size of ?-PGA products was analyzed by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE), and that for characterization of ?-PGA with Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that initial concentrations of L-glutamic acid(0, 15 30, 45, 60, 75 g/L) affected on the production of ?-PGA significantly. In addition, the L-glutamic acid of 75 g/L could contribute the best production of 12.64 g/L ?-PGA, which higher than those concentrations of 45 and 60 g/L L-glutamic acid. Therefore, an increase of the L-glutamic acid concentration correlated well with an increased concentration of ?-PGA polymer. The observations gave an alternative for possible process development of the production of ?-PGA. This is directly applicable in industries, as well as enhancing academic progress in bio-polymer field.

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References

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Published

2012-12-20

How to Cite

[1]
N. . Konglom, C. . Chuensangjun, C. . Pechyen, and S. Sirisansaneeyakul, “Production of poly-?-glutamic acid by <i>Bacillus licheniformis</i>: Synthesis and characterization”, J Met Mater Miner, vol. 22, no. 2, Dec. 2012.

Issue

Vol. 22 No. 2 (2012)

Section

Original Research Articles

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Copyright (c) 2012 Journal of Metals, Materials and Minerals

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