Polymers in Medicine

Polim. Med.
Index Copernicus (ICV 2022) – 121.55
MEiN – 70
Average rejection rate – 39.13%
ISSN 0370-0747 (print)
ISSN 2451-2699 (online) 
Periodicity – biannual

Download PDF

Polymers in Medicine

2018, vol. 48, nr 2, July-December, p. 91–97

doi: 10.17219/pim/105555

Publication type: original article

Language: English

Download citation:

  • BIBTEX (JabRef, Mendeley)
  • RIS (Papers, Reference Manager, RefWorks, Zotero)

Creative Commons BY-NC-ND 3.0 Open Access

Effects of media components and agricultural by-products on γ-polyglutamic acid production by Bacillus toyonensis As8

Olubusola A. Odeniyi1,A,B,C,D,E,F, David S. Avoseh1,B,C,D,E,F

1 University of Ibadan, Nigeria

Abstract

Background. Poly-γ‑glutamic acid (γ‑PGA) provides an environmentally friendly alternative to plastic materials which have widely polluted the environment.
Objectives. The microbial production of γ‑PGA, an amino acid biopolymer with glutamic acid subunits, was investigated using renewable agricultural residues in an attempt to find cheaper substitutes for conventional synthetic media components.
Material and Methods. Bacteria which produce γ‑PGA were isolated through depolymerizing Coix lacryma-jobi, a cellulosic grass, and the effects of various carbon and nitrogen sources, temperature, inoculant load, incubation period, and pH on γ‑PGA yield were determined after submerged fermentation. Bacterial growth was measured turbidimetrically at 550 nm. The γ‑PGA produced was characterized using Fourier transform infrared (FT-IR) spectroscopy and the polymer shape was determined using scanning electron microscopy (SEM).
Results. The best γ‑PGA producer was molecularly identified as Bacillus toyonensis As8. The conditions which produced the highest γ‑PGA yield were glucose, ammonium sulfate, 25°C, a pH of 5.5, and an incubation period of 48 h. This bacterium yielded the most γ‑PGA (26.45 g/L) on cassava peels, while other agro-wastes (corn cob, sorghum leaves, Coix noir leaves, and rice bran) also supported bacterial growth with lower γ‑PGA yields than conventional carbon sources. The wrinkled γ‑PGA had absorbance peaks of hydroxyl, amide, carbonyl, and amine groups comparable with the ranges of those found in commercial γ‑PGA.
Conclusion. The use of agricultural by-products as fermentation substrates increased γ‑PGA yield and may therefore be used as substitute components in γ‑PGA production.

Key words

agricultural wastes, biopolymer synthesis, poly-γ‑glutamic acid characteristics, Bacillus toyonensis

References (26)

  1. Shih IL, Van YT. The production of poly (gamma‑glutamic acid) from microorganisms and its various applications. Bioresour Technol. 2001;79(3):207–225.
  2. Sung MH, Park C, Kim CJ, Poo H, Soda K, Ashiuchi M. Natural and edible biopolymer poly-γ‑glutamic acid: Synthesis, production, and applications. Chem Rec. 2005;5(6):352–366.
  3. Bajaj IB, Singhal RS. Poly (glutamic acid): An emerging biopolymer of commercial interest. Bioresour Technol. 2011;102(10):5551–5561.
  4. Sanda F, Fujiyama T, Endo T. Chemical synthesis of poly-gammaglutamic acid by polycondensation of gamma‑glutamic acid dimer: Synthesis and reaction of poly-gamma‑glutamic acid methyl ester. Polym Sci Chem. 2001;39(5):732–741.
  5. Ogunleye A, Bhat A, Irorere VU, Hill D, Williams C, Radecka I. Poly-γ‑glutamic acid: Production, properties and applications. Microbiology. 2015;161(Pt 1):1–17.
  6. Goto A, Kunioka M. Biosynthesis and hydrolysis of poly (γ‑glutamic acid) from Bacillus subtilis IFO3335. Biosci Biotechnol Biochem. 1992;56(7):1031–1035.
  7. Candela T, Moya M, Haustant M, Fouet A. Fusobacterium nucleatum, the first Gram-negative bacterium demonstrated to produce polyglutamate. Can J Microbiol. 2009;55(5):627–632.
  8. Sakai K, Sonoda C, Murase K, inventors; Bitterness relieving agent. 2000. JP Patent WO0021390.
  9. Bhat AR, Irorere VU, Bartlett T, et al. Improving survival of probiotic bacteria using bacterial poly-γ‑glutamic acid. Int J Food Microbiol. 2015;196:24–31.
  10. Luo Z, Guo Y, Liu J, et al. Microbial synthesis of poly-γ‑glutamic acid: Current progress, challenges, and future perspectives. Biotechnol Biofuels. 2016;9(134):1–12.
  11. Olutiola PO, Famurewa O, Sonntag HG. Introduction to General Microbiology: A Practical Approach. 2nd ed. Ikeja, Nigeria: Bolabay Publications; 2000.
  12. Nagai T, Koguchi K, Itoh Y. Chemical analysis of poly-γ‑glutamic acid produced by plasmid-free Bacillus subtilis (natto): Evidence that plasmids are not involved in poly-γ‑glutamic acid production. J Gen Appl Microbiol. 1997;43(3):139–143.
  13. Kunioka M, Goto A. Biosynthesis of poly (γ‑glutamic acid) from l‑glutamic acid, citric acid, and ammonium sulfate in Bacillus subtilis IFO3335. Appl Microbiol Biotechnol. 1994;40(6):867–872.
  14. Fawole MO, Oso BA. Characterization of Bacteria: Laboratory Manual of Microbiology. 4th ed. Ibadan, Nigeria: Spectrum Book Ltd; 2004.
  15. Seo JH, Kim CS, Lee SP. Physicochemical properties of poly-γ‑glutamic acid production by a novel Bacillus subtilis HA isolated from Cheonggukjang. J Food Sci Nutr. 2008;13(4):354–361.
  16. Tork SE, Aly MM, Alakilli SY, Al-Seeni MN. Purification and characterization of gamma poly glutamic acid from newly Bacillus licheniformis NRC20. Int J Biol Macromol. 2015;74:382–391.
  17. Ho GH, Ho TI, Hsieh KH, et al. γ-Polyglutamic acid produced by Bacillus subtilis (natto): Structural characteristics, chemical properties and biological functionalities. J Chinese Chem Soc Taipei. 2006;53(6):1363–1384.
  18. Kedia G, Hill D, Hill R, Radecka I. Production of poly‑glutamic acid by Bacillus subtilis and Bacillus licheniformis with different growth media. J Nanosci Nanotechnol. 2010;10(9):5926–5934.
  19. Ju WT, Song YS, Jung WJ, Park RD. Enhanced production of poly-γ- glutamic acid by a newly-isolated Bacillus subtilis. Biotechnol Lett. 2014;36(11):2319–2324.
  20. Peng Y, Zhang T, Mu W, Miao M, Jiang B. Intracellular synthesis of glutamic acid in Bacillus methylotrophicus SK19.001, a glutamate independent poly (γ‑glutamic acid)-producing strain. J Sci Food Agric. 2016;96(1):66–72.
  21. Du G, Yang G, Qu Y, Chen J, Lun S. Effects of glycerol on the production of poly (γ‑glutamic acid) by Bacillus licheniformis. Process Biochemistry. 2005;40(6):2143–2147.
  22. Shih IL, Van YT, Chang YN. Application of statistical experimental methods to optimize production of poly(γ‑glutamic acid) by Bacillus licheniformis CCRC 12826. Enzyme and Microbial Technology. 2002;31(3):213–220.
  23. Hezayen FF, Rehm BHA, Eberhardt R, Steinbuchel A. Polymer production by two newly isolated extremely halophilic Archaea: Application of a novel corrosion-resistant bioreactor. Appl Microbiol Biotechnol. 2000;54(3):319–325.
  24. Kimura K, Tran LSP, Uchida I, Itoh Y. Characterization of Bacillus subtilis γ-glutamyltransferase and its involvement in the degradation of capsule poly-γ-glutamate. Microbiology. 2004;150(Pt 12):4115–4123.
  25. Odeniyi OA, Adeola OJ. Production and characterization of polyhydroxyalkanoic acid from Bacillus thuringiensis using different carbon substrates. Int J Biol Macromol. 2017;104(Pt A):407–413.
  26. Bhat AR, Irorere VU, Bartlett T, et al. Bacillus subtilis natto: A non-toxic source of poly-γ‑glutamic acid that could be used as a cryoprotectant for probiotic bacteria. AMB Express. 2013;3(36):1–9.
© Wroclaw Medical University