Journal of Metals, Materials and Minerals
Publication Date
2012-12-01
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.
First Page
7
Last Page
11
Recommended Citation
Konglom, N.; Chuensangjun, C.; Pechyen, C.; and Sirisansaneeyakul, S.
(2012)
"Production of poly-?-glutamic acid by Bacillus licheniformis: Synthesis and characterization,"
Journal of Metals, Materials and Minerals: Vol. 22:
No.
2, Article 2.
Available at:
https://digital.car.chula.ac.th/jmmm/vol22/iss2/2