Economic Consideration of Poly(3-hydroxybutyrate) Production by Fed-batch Culture of Ralstonia eutropha KHB 8862

Ralstonia eutropha의 유가식 발효에 의한 Poly(3-hydroxybutyrate) 생산의 경제성 분석

  • Published : 2001.03.01

Abstract

High-cell-density cultivation of Ralstonia eutopha KHB 8862 by fed-batch fermentation in a 200 l pilot plant was carried out for the mass production of poly(3-hydroxybutyrate) (PHB). After 80 h of cultivation, the dry cell weight (DCW), PHB concentration, and PHB yield from fructose syrup reached 168 g/l, 74%DCW, and 0.27 (w/w), respectively, resulting in a productivity of 1.6 g of PHB/L/h. Based on these results, the PHB production cost from bacterial fermentation was analyzed and economic evaluation was performed. In the case of new investment being implemented or not, the production cost of PHB was US$ 3.15/kg and US$ 2.41/kg, respectively. PHB productivity and PHB yield on a carbon substrate were both important factors to be optimized. The increase of PHB yield on a carbon sources significantly decreased the PHB production cost but the increase in productivity had a relatively slight effect on the decrease in PHB production cost because the cost of carbon sources (37%) for PHB was larger in proportion to total cost than the depreciation cost (17%). These results suggest that the increased PHB yield from carbon sources and the development of new cheaper substrates would be more effective in decreasing PHB production cost than the increase in productivity. It was demonstrated that PHB is not in competition with consumable plastics such as PET in present market. Therefore, it is essential to lower production cost to be used as a bulk product and desirable to develop new application fields for PHB such as biomedical and cosmeceuticals.

Pi1ot plant (200 l)에서의 유가식 배양에 의한 Ralstonia eutopha KHB 8862의 고농도 배 양을 통하여 Poly(3-hydroxybutyrate) (PHB)의 대량생산을 모색하였다. 그 결과 배양 80시간 후 168 g/l의 건체량과 건체량의 74%에 달하는 PHB를 생산할 수 있었으며, 이때의 고과당 시럽으로부터의 PHB 전환수율 및 PHB 생산성은 각각 0.27 (w/w) 및 1.6 $gl^{-1}$ $h^{-1}$ /이었다. 이를 토대로 본 연구에서는 미생물 발효에 의한 PHB 생산 cost 및 그 경제성을 분석하였다. 신규설비투자를 고려하지 않은 경우의 PHB의 생산 cost는 US$2.41/kg으로 산출된 반면에 신규 설비투자를 고려한 경우에는 US$3.15/kg으로 상승되었다. 탄소원의 PHB로의 전환수율과 발효 생산성 모두 PHB 생산비를 결정하는 중요요인이지만 전체 생산비의 37%를 차지하는 탄소원 원료비의 비중이 설비투자의 감가상각비 비중 (17%)에 비해 높기 때문에 생산성을 높이는 노력보다는 전환수율을 개선하는 것이 PHB 생산비용 절감의 핵심이 되는 것으로 나타났다. PHB chip으로의 제조시 PHB 생산 cost는 US$4.0/kg의 수준으로 현재로서는 범용 합성플라스틱에 비하여 경쟁력을 확보하지 못한다. 따라서 생산비 절감을 통한 범용수지로써 경쟁력 제고와 함께 바이오의약 분야 등의 고부가가치 영역에서의 새로운 용도 개발 등이 적극 요구된다.

Keywords

References

  1. Polymer International v.47 A review of biodegradable polymers: use, current developments in the synthesis and characterization of biodegradable polyesters, blends of biodegradable polymers and recent advances in biodegradation sutdies Amass, W.;A. Amass;B. Tighe
  2. Microbiol. Rev. v.54 Occurrence, metabolism, metabolic role, and industrial use of bacterial polyhydroxyal-kanoates Anderson, A.J.;E.A. Dawes
  3. Eur. J. Appl. Microbiol. Biotechnol. v.6 A rapid method for the determination of poly-ß-hydroxybutyric acid in microbial biomass Braunegg, G.;B. Sconnleitner;R.M. Lafferty
  4. FEMS Micrbiol. Rev. v.103 Production of poly-ß-hydroxybutyrate : poly-ß-hydroxyvalerate copolymers Byrom, D.
  5. Bioprocess Eng. v.17 Process analysis and economic evaluation for poly(3-hydroxybutyrate) production by fermentation Choi, J.;S.Y. Lee
  6. Appl. Microbiol. Biotechnol. v.51 Factors affecting the economics of polyhydroxyalkanoate production by bacterial fermentation Choi, J.;S.Y. Lee
  7. Biotechnol. Bioeng. v.62 Efficient and economical recovery of poly(3-hydroxybutyrate) from recombinant Escherichia coli by simple digestion with chemicals Choi, J.;S.Y. Lee
  8. Appl. Microbiol. Biotechnol. v.53 Economic considerations in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by bacterial fermentation Choi, J.;S.Y. Lee
  9. J. Biomed. Mater. Res. v.27 Tissue response and in vivo degradation of selected polyhydroxyacids: Ploylactides (PLS), poly(3-hydroxybutyrate) (PHB), and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB/VA) Gogolewski, S.;M. Jovanovic;S.M. Perre;J.G. Dillon;M. K. Hughes
  10. Appl. Microbiol. Biotechnol. v.48 Efficient production of medium-chain length poly(3-hydroxyalkanoates) from octane by pseudomonas oleovoran: economic considerations Hazenberg, W.;B. Witholt
  11. Single cell protein Product outlook and technical feasibility of SCP Humphrey, A.E.;Tannenbaum, S.R.(ed.);Wang D.I.C.(ed.)
  12. Int. J. Biol. Macromol. v.28 Evaluation of various carbon substrates for the biosynthesis of polyhydroxyalkanoates bearing functional groups by Pseudomonas oleovorans Kim, D.Y.;Y.B. Kim;Y.H. Rhee
  13. Biotechnol. Lett. v.22 Preparation and characterization of native poly(3-hydroxybutyrate) microspheres from Ralstonia eutropha Kim, G.J.;K.H. Bang;Y.B. Kim;Y.H. Rhee
  14. Continuous culture 6. Application and new field Single cell protein from starch MacLennan, D.G.;Dean A.C.R.(ed.);Ellwood, D.C.(ed.);Evans, C.G.T.(ed.);Melling, J.(ed.)
  15. Microbiol. Mol. Biol. Rev. v.63 Metabolic engineering of poly(3-hydroxyalkanoates): from DNA to plastic Madison, L.L.;G.W. Huisman
  16. Proc. Biochem. v.14 SCP from methanol: The norprotein process Mogren, H.
  17. Ann. Rep. Ferm. Processes v.1 Economic status of fermentation processes Nyiri, L.K.;M. Charles
  18. Appl. Environ. Microbiol. v.59 Growth of Azotobacter vinelandii UWD in fish peptone medium and simplified extraction of poly-ß-hydroxybutyrate Page, W.J.;A. Comish
  19. Principles of fermentation technology Stanbury, P.F.;A. Whitaker
  20. Polymer v.35 Polymer review: polymer blends containing poly(3-hydroxyalkanoate)s Verhoogt, H.;B.A. Ramsay;B.D. Favis
  21. Biotechnol. Bioeng. v.41 Yield of poly D(-)-3hydroxybutyrate from various carbon sources: a theoretical study Yamane, T.
  22. J. Ferment. Bioeng. v.80 Effects of amino acid additions on molar fraction of 3-hydroxyvalerate in copolyester of 3-hydroxybutyrate and 3-hydroxyvalerate synthesized by Alcaligenes sp. SH-69 Yoon, J.S.;J.Y. Kim;Y.H. Rhee