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Bioethanol Production from Gracilaria verrucosa Using Saccharomyces cerevisiae with Adaptive Evolution

Galactose에 순치한 Saccharomyces cerevisiae를 이용하여 꼬시래기(Gracilaria verrucosa)로부터 바이오에탄올 생산

  • Yang, Ji Won (Department of Biotechnology, Pukyong National University) ;
  • Park, Yu Rim (Department of Biotechnology, Pukyong National University) ;
  • Jeong, Gwi-Taek (Department of Biotechnology, Pukyong National University) ;
  • Kim, Sung-Koo (Department of Biotechnology, Pukyong National University)
  • 양지원 (부경대학교 생물공학과) ;
  • 박유림 (부경대학교 생물공학과) ;
  • 정귀택 (부경대학교 생물공학과) ;
  • 김성구 (부경대학교 생물공학과)
  • Received : 2020.09.09
  • Accepted : 2020.11.24
  • Published : 2021.03.28

Abstract

The seaweed, Gracilaria verrucosa (red seaweed) was fermented to produce bioethanol. Optimal thermal acid hydrolysis conditions were determined as 200 mM H2SO4 and 10% (w/v) seaweed slurry at 130℃ for 60 min yielding 47.5% of pretreatment efficiency (Ep). After the thermal acid hydrolysis, enzymatic saccharification was carried out with 16 U/ml Viscozyme L, Cellic CTec2 or mixture of Viscozyme L and Cellic CTec2 to G. verrucosa hydrolysates. Enzymatic saccharifications with Viscozyme, Cellic CTec2 or mixture of those yielded 7.3 g/l glucose with efficiency of saccharification, Es = 34.9%, 11.6 g/l glucose with Es = 64.4% and the mixture of those 9.6 g/l glucose with Es = 56.6%, respectively. Therefore, based on the Es value, Cellic CTec2 was selected for the optimal enzyme for enzymatic saccharification of G. verrucosa hydrolysate. The ethanol productions with non-adapted S. cerevisiae CEN-PK2 (wild type) and S. cerevisiae CEN-PK2 with adaptive evolution to galactose produced 8.5 g/l ethanol with YEtOH = 0.19 and 21.5 g/l ethanol with YEtOH = 0.50 at 144 h, respectively. From these results, the ethanol production by S. cerevisiae with adaptive evolution showed high concentration of ethanol production using G. verrucosa as a substrate.

해조류 중 홍조류인 꼬시래기(G. verrucosa)로부터 효모를 이용한 발효를 위해 열산가수분해, 효소당화 및 에탄올 발효수율 향상을 검토하고, 기존의 혼합당의 흡수효율을 높이기 위해 고농도 당 순치를 수행하였다. 열산가수분해는 200 mM 황산(H2SO4)을 이용하여 10% (w/v)의 꼬시래기(G. verrucosa)의 슬러리, 130℃의 온도에서 60분 동안 열산가수분해를 수행하였다. 또한 wild type 효모와 고농도 galactose에 순치(adaptive evolution)된 효모를 이용한 발효를 실시한 결과, wild type 효모의 경우 발효 144시간에 8.5 g/l 에탄올 발효로 에탄올수율계수 YEtOH = 0.19와 galactose에 순치된 효모의 경우 21.5 g/l 에탄올 발효로 에탄올수율계수 YEtOH = 0.50을 나타내었다. 이러한 연구결과는 해양 바이오매스인 해조류로부터 바이오 연료의 효율적인 생산방법을 제공할 수 있을 것으로 판단된다.

Keywords

Acknowledgement

This work was supported by a Research Grant of Pukyong National University (year 2019).

References

  1. Sabourin-Provost G, Hallenbeck PC. 2009. High yield conversion of a crude glycerol fraction from biodiesel production to hydrogen by photofermentation. Bioresour. Technol. 100: 3513-3517. https://doi.org/10.1016/j.biortech.2009.03.027
  2. Yazdani SS, Gonzalez R. 2007. Anaerobic fermentation of glycerol: a path to economic viability for the biofuels industry. Curr. Opin. Biotechnol. 18: 213-219. https://doi.org/10.1016/j.copbio.2007.05.002
  3. Cazetta ML, Celligoi MAPC, Buzato JB, Scarmino IS. 2007. Fermentation of molasses by Zymomonas mobilis: effects of temperature and sugar concentration on ethanol production. Bioresour. Technol. 98: 2824-2828. https://doi.org/10.1016/j.biortech.2006.08.026
  4. Bothast RJ, Schlicher MA. 2005. Biotechnological processes for conversion of corn into ethanol. Appl. Microbiol. Biotechnol. 67: 19-25. https://doi.org/10.1007/s00253-004-1819-8
  5. Daroch M, Geng S, Wang G. 2013. Recent advances in liquid biofuel production from algal feedstocks. Appl. Energy 102: 1371-1381. https://doi.org/10.1016/j.apenergy.2012.07.031
  6. Dias MOS, Esinas AV, Nebra SA, Filho RM, Rossel CEV, Maciel MRW. 2009. Production of bioethanol and other bio-based materials from sugarcane bagasse. Chem. Eng. Res. Des. 87: 1206-1216. https://doi.org/10.1016/j.cherd.2009.06.020
  7. Chiaramonti D, Prissi M, Ferrero S, Oriani L, Ottonello P, Torre P, et al. 2012. Review of pretreatment processes for lignocellulosic ethanol production. Biomass Bioenergy 46: 25-35. https://doi.org/10.1016/j.biombioe.2012.04.020
  8. Kim MJ, Kim SK. 2012. Ethanol production by separate hydrolysis and fermentation and simultaneous saccharification and fermentation using Saccharina japonica. KSBB J. 27: 86-90. https://doi.org/10.7841/ksbbj.2012.27.2.086
  9. Adamas JM, Gallagher JA, Donnison LS. 2009. Fermentation study on Saccharina latissimi for bioethanol production considering variable pre-treatments. J. Appl. Phycol. 21: 569. https://doi.org/10.1007/s10811-008-9384-7
  10. Agbor VB, Cicek N, Sparling R, Berlin A, Levin DB. 2011. Biomass pretreatment: fundamentals toward application. Biotechnol. Adv. 29: 675-685. https://doi.org/10.1016/j.biotechadv.2011.05.005
  11. Morimoto S, Murakami M. 1993. Biotransformation of furfural and 5-hydroxymethyl furfural by enteric bacteria. J. Ind. Microbiol. 11: 147-150. https://doi.org/10.1007/BF01583715
  12. Sanchez-Machado DI, Lopez-Cervantes J, Paseiro-Losada P, Lopez-Hernandez J. 2004. Fatty acids, total lipid, protein and ash contents of processed edible seaweeds. Food. Chem. 85: 439-444. https://doi.org/10.1016/j.foodchem.2003.08.001
  13. Cho Y, Ra CH, Kim SK. 2014. Ethanol production from the seaweed Gelidium amansii, using specific sugar acclimated yeasts. J. Microbiol. Biotechnol. 24: 264-269. https://doi.org/10.4014/jmb.1307.07054
  14. Cho Y, Kim H, Kim SK. 2013. Bioethanol production from brown seaweed, Undaria pinnatifida, using NaCl acclimated yeast. Bioprocess Biosyst. Eng. 36: 713-719. https://doi.org/10.1007/s00449-013-0895-5
  15. Qi L, Mui YF, Lo SW, Lui MY, Akien GR, Horvath IT. 2014. Catalytic conversion of fructose, glucose and sucrose to 5-(hydroxymethyl) furfural and levulinic and formic acids in γ-valerolactone as a green solvent. ACS. Catal. 4: 1470-1477. https://doi.org/10.1021/cs401160y
  16. Guo Z, Olsson L. 2014. Physiological response of Saccharomyces cerevisiae to weak acids present in lignocellulosic hydrolysate. FEMS Yeast. Res. 14: 1234-1248. https://doi.org/10.1111/1567-1364.12221
  17. Linihan P, Orozco A, O'Neill E, Ahmad MNM, Rooney DW, Walker GM. 2010. Dilute acid hydrolysis of lignocellulosic biomass. Chem. Eng. J. 156: 395-403. https://doi.org/10.1016/j.cej.2009.10.061
  18. Ra CH, Choi JG, Kang CH, Sunwoo IY, Jeong GT, Kim SK. 2015. Thermal acid hydrolysis pretreatment, enzymatic saccharification and ethanol fermentation from red seaweed, Gracilaria verrucosa. Microbiol. Biotechnol. Lett. 41: 9-15.