Bioupgrading of the aqueous phase of pyrolysis oil from lignocellulosic biomass: a platform for renewable chemicals and fuels from the whole fraction of biomass

Abstract

Pyrolysis, a thermal decomposition without oxygen, is a promising technology for transportable liquids from whole fractions of lignocellulosic biomass. However, due to the hydrophilic products of pyrolysis, the liquid oils have undesirable physicochemical characteristics, thus requiring an additional upgrading process. Biological upgrading methods could address the drawbacks of pyrolysis by utilizing various hydrophilic compounds as carbon sources under mild conditions with low carbon footprints. Versatile chemicals, such as lipids, ethanol, and organic acids, could be produced through microbial assimilation of anhydrous sugars, organic acids, aldehydes, and phenolics in the hydrophilic fractions. The presence of various toxic compounds and the complex composition of the aqueous phase are the main challenges. In this review, the potential of bioconversion routes for upgrading the aqueous phase of pyrolysis oil is investigated with critical challenges and perspectives.

Keywords

Lignocellulosic biomass / Pyrolysis oil / Aqueous phase / Biological conversion / Toxicity mitigation

References

[1] Acosta AM, Cosovanu D, López PC, . Co-cultivation of a novel Fusarium striatum strain and a xylose consuming Saccharomyces cerevisiae yields an efficient process for simultaneous detoxification and fermentation of lignocellulosic hydrolysates. Chem Eng J, 2021, 426: 131575.

[2] Ahamed TS, Anto S, Mathimani T, Brindhadevi K, Pugazhendhi A. Upgrading of bio-oil from thermochemical conversion of various biomass - mechanism, challenges and opportunities. Fuel, 2021, 287: 119329.

[3] Ahmad AA, Zawawi NA, Kasim FH, Inayat A, Khasri A. Assessing the gasification performance of biomass: A review on biomass gasification process conditions, optimization and economic evaluation. Renew Sust Energ Rev, 2016, 53: 1333-1347.

[4] Arnold S, Moss K, Henkel M, Hausmann R. Biotechnological perspectives of pyrolysis oil for a bio-based economy. Trends Biotechnol, 2017, 35: 925-936.

[5] Arnold S, Henkel M, Wanger J, Wittgens A, Rosenau F, Hausmann R. Heterologous rhamnolipid biosynthesis by P. putida KT2440 on bio-oil derived small organic acids and fractions. AMB Expr, 2019, 9: 80.

[6] Arnold S, Moss K, Dahmen N, Henkel M, Hausmann R. Pretreatment strategies for microbial valorization of bio-oil fractions produced by fast pyrolysis of ash-rich lignocellulosic biomass. GCB Bioenergy, 2019, 11: 181-190.

[7] Attia M, Farag S, Chaouki J. Upgrading of oils from biomass and waste: catalytic hydrodeoxygenation. Catal, 2020, 10: 1381.

[8] Badger PC. Janick J, Whipkey A. Ethanol from cellulose: A general review. Trends in new crops and new uses, 2002, Alexandria: ASHS Press, 17-20.

[9] Baloch HA, Nizamuddina S, Siddiqui MTH, Riaz S, Jatoi AS, Dumbre DK, Mubarak NM, Srinivasan MP, Griffin GJ. Recent advances in production and upgrading of bio-oil from biomass: a critical review. J Environ Chem Eng, 2018, 6: 5101-5118.

[10] Bang J, Lee SY. Assimilation of formic acid and CO₂ by engineered Escherichia coli equipped with reconstructed one-carbon assimilation pathways. Proc Natl Acad Sci USA, 2018, 115: E9271-E9279.

[11] Basaglia M, Favaro L, Torri C, Casella S. Is pyrolysis bio-oil prone to microbial conversion into added-value products?. Renew Energy, 2021, 163: 783-791.

[12] Bennett NM (2006) Fermentable sugars from pyrolysis oil: extraction and hydrolysis of levoglucosan. Dissertation, University of British Columbia

[13] Bertero M, de la Puente G, Sedran U. Fuels from bio-oils: bio-oil production from different residual sources, characterization and thermal conditioning. Fuel, 2012, 95: 263-271.

[14] Bhatia SK, Gurav R, Choi TR, . Bioconversion of plant biomass hydrolysate into bioplastic (polyhydroxyalkanoates) using Ralstoniaeutropha 5119. Bioresour Technol, 2019, 271: 306-315.

[15] Bridgwater AV. Review of fast pyrolysis of biomass and product upgrading. Biomass Bioenergy, 2012, 38: 68-94.

[16] Bridgwater AV. Rabaçal M, Ferreira A, Silva C, Costa M. Biomass conversion technologies: fast pyrolysis liquids from biomass: quality and upgrading. Biorefineries, 2017, Cham: Springer, 55-98. 10.1007/978-3-319-48288-0_3

[17] Bridgwater AV, Peacocke GVC. Fast pyrolysis processes for biomass. Renew Sust Energy Rev, 2000, 1: 1-73.

[18] Brown RC. Hybrid thermochemical/biological processing: putting the cart before the horse?. Appl Biochem Biotechnol, 2007, 137: 947-956.

[19] Chan YH, Loh SK, Chin BLF, Yiin CL, How BS, Cheah KW, Wong MK, Loy ACM, Gwee YL, Lo SLY, Yusup S, Lam SS. Fractionation and extraction of bio-oil for production of greener fuel and value-added chemicals: recent advances and future prospects. Chem Eng J, 2020, 397: 125406.

[20] Chang D, Wang C, Ndayisenga F, Yu Z. Mutations in adaptively envolved Esherichia coli LGE2 facilitated the cost-effective upgrading of undetoxified bio-oil to bioethanol fuel. Bioresour Bioprocess, 2021, 8: 105.

[21] Clark DP, Cronan J. Neidhardt FC, Curtiss R. Two-carbon compounds and fatty acids as carbon sources. Escherichia coli and Salmonella : cellular and molecular biology, 1996, 2, Washington: ASM press, 343-357.

[22] Czernik S, Bridgwater AV. Overview of applications of biomass fast pyrolysis oil. Energy Fuels, 2004, 18: 590-598.

[23] Demirbas A. Combustion characteristics of different biomass fuels. Prog Energy Combust Sci, 2004, 30: 219-230.

[24] Demirbas A. Biorefineries: current activities and future developments. Energy Convers Manag, 2009, 50: 2782-2801.

[25] Dhyani V, Bhaskar T. A comprehensive review on the pyrolysis of lignocellulosic biomass. Renew Energy, 2018, 129: 695-716.

[26] Di Blasi C, Signorelli G, Di Russo C, Rea G. Product distribution from pyrolysis of wood and agricultural residues. Ind Eng Chem Res, 1999, 38: 2216-2224.

[27] Doddapaneni TRKC, Kikas T. Fang Z, Smith RL Jr, Xu L. Integrating biomass pyrolysis with microbial conversion processes to produce biofuels and biochemicals. Production of biofuels and chemicals with pyrolysis biofuels and biorefineries, 2020, Singapore: Springer, 235-263.

[28] Habe H, Sato Y, Kirimura J. Microbial and enzymatic conversion of levulinic acid, an alternative building block to fermentable sugars from cellulosic biomass. Appl Microbiol Biotechnol, 2020, 104: 7767-7775.

[29] Hasan SA, Jabeen S. Degradation kinetics and pathway of phenol by Pseudomonas and Bacillus species. Biotechnol Biotechnol Equip, 2015, 29: 45-53.

[30] Henson WR, Meyers AW, Jayakody LN, . Biological upgrading of pyrolysis-derived wastewater: engineering Pseudomonas putida for alkylphenol, furfural, and acetone catabolism and (methyl)muconic acid production. Metab Eng, 2021, 68: 14-25.

[31] Hu X, Li C, Xu Y, Wang Q, Zhu X. On the thermal oxidation stability of pyrolysis biomass oil. Int J Renew Energy Technol, 2011, 2: 155.

[32] Huang X, Liu J, Lu L, Peng K, Yang G, Liu J. Culture strategies for lipid production using acetic acid as sole carbon source by Rhodosporidiumtoruloides. Bioresour Technol, 2016, 206: 141-149.

[33] Ioannidou O, Zabaniotou A, Antonakou EV, Papazisi KM, Lappas AA, Athanassiou C. Investigating the potential for energy, fuel, materials and chemicals production from corn residues (cobs and stalks) by non-catalytic and catalytic pyrolysis in two reactor configurations. Renew Sustain Energy Rev, 2009, 13: 750-762.

[34] Islam ZU, Zhisheng Y, Hassan EB, Dongdong C, Hongxun Z. Microbial conversion of pyrolytic products to biofuels: a novel and sustainable approach toward second-generation biofuels. J Ind Microbiol Biotechnol, 2015, 42: 1557-1579.

[35] Islam ZU, Klykov SP, Yu Z, Chang D, Hassan EB, Zhang H. Fermentation of detoxified acid-hydrolyzed pyrolytic anhydrosugars into bioethanol with Saccharomyces cerevisiae 2.399. Appl Biochem Microbiol, 2018, 54: 58-70.

[36] Jayakody LN, Ferdouse J, Hayashi N, Kitagaki H. Identification and detoxification of glycolaldehyde, an unattended bioethanol fermentation inhibitor. Crit Rev Biotechnol, 2017, 37: 177-189.

[37] Jayakody LN, Turner TL, Yun EJ, . Expression of Gre2p improves tolerance of engineered xylose-fermenting Saccharomyces cerevisiae to glycolaldehyde under xylose metabolism. Appl Microbiol Biotechnol, 2018, 102: 8121-8133.

[38] Jena U, Das KC. Comparative evaluation of thermochemical liquefaction and pyrolysis for bio-oil production from microalgae. Energy Fuels, 2011, 25: 5472-5482.

[39] Jiménez-Bonilla P, Zhang J, Wang Y, Blersch D, . Enhancing the tolerance of Clostridium saccharoperbutylacetonicum to lignocellulosic-biomass-derived inhibitors for efficient biobutanol production by overexpressing efflux pumps genes from Pseudomonas putida. Bioresour Technol, 2020, 312: 123532.

[40] Junior II, Do Nascimento MA, De Souza ROMA, Dufour A, Wojcieszak R. Levoglucosan: a promising platform molecule?. Green Chem, 2020, 22: 5859.

[41] Kanhounnon WG, Kuevi UA, Kpotin GA, Koudjina S, Houngue AK, Atohoun GYS, Mensah JB, Badawi M. Quantum mechanistic study of furan and 2-methylfuran hydrodeoxygenation on molybdenum and tungsten sulfide clusters. J Mol Model, 2019, 25: 237.

[42] Kim SY, Yang YH, Choi KY. Bioconversion of plant hydrolysate biomass into biofuels using an engineered Bacillus subtilis and Escherichia coli mixed-whole cell biotransformation. Biotechnol Bioproc Eng, 2020, 25: 477-484.

[43] Kubisch C, Ochsenreither K. Valorization of a pyrolytic aqueous condensate and its main components for L-malic acid production with Aspergillus oryzae DSM 1863. Ferment, 2022, 8: 107.

[44] Kumari G, Karmee SK. Sahay S. Thermochemical routes applying biomass: a critical assessment. Handbook of biofuels, 2022, San Diego: Academic Press, 435-451. 10.1016/B978-0-12-822810-4.00022-1

[45] Lange J, Müller F, Bernecker K, . Valorization of pyrolysis water: a biorefinery side stream, for 1,2-propanediol production with engineered Corynebacterium glutamicum. Biotechnol Biofuels, 2017, 10: 277.

[46] Layton DS, Ajjarapu A, Choi DW, Jarboe LR. Engineering ethanologenic Escherichia coli for levoglucosan utilization. Bioresour Technol, 2011, 102: 8318-8322.

[47] Lee SY, Kim YH, Min J. Conversion of phenol to glutamate and proline in Corynebacterium glutamicum is regulated by transcriptional regulator ArgR. Appl Microbiol Biotechnol, 2010, 85: 713-720.

[48] Lee SA, Wrona LJ, . Isolation and characterization of bacteria that use furans as the sole carbon source. Appl Biochem Biotechnol, 2016, 178: 76-90.

[49] Lee SY, Sankaran R, Chew KW, Tan CH, Krishnamoorthy R, Chu DT, Show PL. Waste to bioenergy: a review on the recent conversion technologies. BMC Energy, 2019, 1: 4.

[50] Lee S, Sohn J, Bae J, Kim S, Sung BH. Current status of Pseudomonas putida engineering for lignin valorization. Biotechnol Bioproc Eng, 2020, 25: 862-871.

[51] Lian J, Chen S, Zhou S, Wang Z, O’Fallon J, Li C-Z, Garcia-Perez M. Separation, hydrolysis and fermentation of pyrolytic sugars to produce ethanol and lipids. Bioresour Technol, 2010, 101: 9688-9699.

[52] Lian J, Garcia-Perez M, Coates R, Wu H, Chen S. Yeast fermentation of carboxylic acids obtained from pyrolytic aqueous phases for lipid production. Bioresour Technol, 2012, 118: 177-186.

[53] Lian J, Garcia-Perez M, Chen S. Fermentation of levoglucosan with oleaginous yeasts for lipid production. Bioresour Technol, 2013, 133: 183-189.

[54] Lian J, Mckenna R, Rover MR, Nielsen DR, Wen Z, Jarboe LR. Production of biorenewable styrene: utilization of biomass-derived sugars and insights into toxicity. J Ind Microbiol Biotechnol, 2016, 43: 595-604.

[55] Lian X, Xue Y, Xu G, Han S, Yu H. Progress on upgrading methods of bio-oil: A review. Int J Energy Res, 2017, 41: 1798-1816.

[56] Liang Y, Zhao X, Chi Z, Rover M, Johnston P, Brown R, . Utilization of acetic acid-rich pyrolytic bio-oil by microalga Chlamydomonas reinhardtii: reducing bio-oil toxicity and enhancing algal toxicity tolerance. Bioresour Technol, 2013, 133: 500-506.

[57] Liang J, Qian Y, . Span80/Tween80 stabilized bio-oil-in-diesel microemulsion: formation and combustion. Renew Energy, 2018, 126: 774-782.

[58] Linger JG, Vardon DR, Guarnieri MT, Karp EM, Hunsinger GB, Franden MA, . Lignin valorization through integrated biological funneling and chemical catalysis. Proc Natl Acad Sci USA, 2014, 111: 12013-12018.

[59] Lu X, Liu Y, Yang Y, . Constructing a synthetic pathway for acetyl-coenzyme A from one-carbon through enzyme design. Nat Commun, 2019, 10: 1378.

[60] Luo H, Gao L, Liu Z, Shi Y, Xie F, Bilal M, Yang R, Taherzadeh MJ. Prediction of phenolic compounds and glucose content from dilute inorganic acid pretreatment of lignocellulosic biomass using artificial neural network modelling. Bioresour Bioprocess, 2021, 8: 134.

[61] Luque L, Orr VCA, Chen S, Westerhof R, Oudenhoven S, van Rossum G, Kersten S, Berruti F, Rehmann L. Lipid accumulation from pinewood pyrolysates by Rhodosporidiumdiobovatum and Chlorellavulgaris for biodiesel production. Bioresour Technol, 2016, 214: 660-669.

[62] Luthfi N, Ohkoshi T, Tamaru Y, Fukushima T, Takisawa K. Investigation into the combustion kinetics and spontaneous ignition of sweet sorghum as energy resource. Bioresour Bioprocess, 2022, 9: 49.

[63] McKendry P. Energy production from biomass (part 2): overview of biomass. Bioresour Technol, 2002, 83: 37-46.

[64] Meier D. Wagemann K, Tippkötter N. Pyrolysis oil biorefinery. Biorefineries. Advances in biochemical engineering/biotechnology, 2017, Cham: Springer, 301-337 10.1007/10_2016_68

[65] Meier D, van de Beld B, Bridgwater AV, Elliott DC, Oasmaa A, Preto F. State-of-the-art of fast pyrolysis in IEA bio-energy member countries. Renew Sustain Energy Rev, 2013, 20: 619-641.

[66] Miller EN, Jarboe LR, Yomano LP, York SW, Shanmugam KT, Ingram LO. Silencing of NADPH-dependent oxidoreductase genes (yqhD and dkgA) in furfural-resistant ethanologenic Escherichia coli. Appl Environ Microbiol, 2009, 75: 4315-4323.

[67] Milne T, Agblevor F, Davis M, Deutch S, Johnson D. Bridgwater AV, Boocock DGB. A review of the chemical composition of fast-pyrolysis oils from biomass. Developments in thermochemical biomass conversion, 1997, Dordrecht: Springer, 409-424. 10.1007/978-94-009-1559-6_32

[68] Mohan D, Pittman CU Jr, Steele PH. Pyrolysis of wood/biomass for bio-oil: a critical review. Energy Fuels, 2006, 20: 848-889.

[69] Monlau F, Sambusiti C, Barakat A, Quemeneur M, Trably E, Steyer JP, Carrèrea H. Do furanic and phenolic compounds of lignocellulosic and algae biomass hydrolysate inhibit anaerobic mixed cultures? A comprehensive review. Biotechnol Adv, 2014, 32: 934-951.

[70] Moradian JM, Fang Z, Yong YC. Recent advances on biomass-fueled microbial fuel cell. Bioresour Bioprocess, 2021, 8: 14.

[71] Mortensen PM, Grunwaldt JD, Jensen PA, Knudsen KG, Jensen AD. A review of catalytic upgrading of bio-oil to engine fuels. Appl Catal A Gen, 2011, 407: 1-19.

[72] Nakagawa M, Sakai Y, Yasui T. Itaconic acid fermentation of levoglucosan. J Ferment Technol, 1984, 62: 201-203.

[73] Neumann A, Dörsam S, Oswald F, Ochsenreither K. Xian M. Microbial production of value-added chemicals from pyrolysis oil and syngas. Sustainable production of bulk chemicals, 2016, Dordrecht: Springer, 69-105. 10.1007/978-94-017-7475-8_4

[74] Nguyen TY, Cai CM, Kumar R, Wyman CE. Overcoming factors limiting high-solids fermentation of lignocellulosic biomass to ethanol. Proc Natl Acad Sci USA, 2017, 114: 11673-11678.

[75] Oasmaa A, Czernik S. Fuel oil quality of biomass pyrolysis oils- state of the art for the end-users. Energy Fuels, 1999, 13: 914-921.

[76] Palazzolo MA, Garcia-Perez M. Microbial lipid biosynthesis from lignocellulosic biomass pyrolysis products. Biotechnol Adv, 2021, 54: 107791.

[77] Palmqvist E, Hahn-Hagerdal B. Fermentation of lignocellulosic hydrolysates. II: inhibitors and mechanisms of inhibition. Bioresour Technol, 2000, 74: 25-33.

[78] Park H, Jeon BS, Sang B. Efficient, simple production of corresponding alcohols from supplemented C2–C8 carboxylic acids in Escherichiacoli using acyl-coA transferase from Megasphaerahexanoica. Biotechnol Bioproc Eng, 2020, 25: 599-606.

[79] Schmollack M, Werner F, Huber J, Kiefer D, Merkel M, Hausmann R, Siebert D, Blombach B. Metabolic engineering of Corynebacterium glutamicum for acetate-based itaconic acid production. Biotechnol Biofuels Bioprod, 2022, 15: 139.

[80] Singh B, Verma A, Pooja MPK, Datta S. A biotechnological approach for degradation of inhibitory compounds present in lignocellulosic biomass hydrolysate liquor usingBordetellasp. BTIITR Chem Eng J, 2017, 328: 519-526.

[81] Song QH, Nie JQ, Ren MG, Guo QX. Effective phase separation of biomass pyrolysis oils by adding aqueous salt solutions. Energy Fuels, 2009, 23: 3307-3312.

[82] Staš M, Kubička D, Chudoba J, Pospĺšil M. Overview of analytical methods used for chemical characterization of pyrolysis bio-oil. Energy Fuels, 2014, 28: 385-402.

[83] Sukhbaatar B, Li Q, Wan C, Yu F, Hassan E-B, Steele P. Inhibitors removal from bio-oil aqueous fraction for increased ethanol production. Bioresour Technol, 2014, 161: 379-384.

[84] Torri C, Fabbri D. Biochar enables anaerobic digestion of aqueous phase from intermediate pyrolysis of biomass. Bioresour Technol, 2014, 172: 335-341.

[85] Tu P, Zhang G, Wei G, Li J, Li Y, Deng L, Yuan H. Influence of pyrolysis temperature on the physicochemical properties of biochars obtained from herbaceous and woody plants. Bioresour Bioprocess, 2022, 9: 131.

[86] Valle B, Remiro A, Garcia-Gomez N, Gayubo AG, Bilbao J. Recent research progress on bio-oil conversion into bio-fuels and raw chemicals: a review. J Chem Technol Biotechnol, 2019, 94: 670-689.

[87] Vardon DR, Franden MA, Johnson CW, Karp EM, Guarnieri MT, Linger JG, . Adipic acid production from lignin. Energy Environ Sci, 2015, 8: 617-628.

[88] Vitasari CR, Meindersma GW, de Haan AB. Water extraction of pyrolysis oil: the first step for the recovery of renewable chemicals. Bioresour Technol, 2011, 102: 7204-7210.

[89] Waisman H, Bataille C, Winkler H, . A pathway design framework for national low greenhouse gas emission development strategies. Nat Clim Chang, 2019, 9: 261-268.

[90] Wang X, Miller EN, Yomano LP, Zhang X, Shanmugam KT, Ingram LO. Increased furfural tolerance due to overexpression of NADH-dependent oxidoreductase FucO in Escherichia coli strains engineered for the production of ethanol and lactate. Appl Environ Microbiol, 2011, 77: 5132-5140.

[91] Wang C, Thygesen A, Liu Y, . Bio-oil based biorefinery strategy for the production of succinic acid. Biotechnol Biofuels, 2013, 6: 74.

[92] Xie HJ, Zhuang XL, . Screening and identification of the levoglucosan kinase gene (lgk) from Aspergillus niger by LC-ESI-MS/MS and RT-PCR. FEMS Microbiol Lett, 2005, 251: 313-319.

[93] Xu L, Jiang L, Zhang H, Fang Z, Smith RL Jr. Fang Z, Smith RL Jr, Xu L. Introduction to pyrolysis as a thermo-chemical conversion technology. Production of Biofuels and Chemicals with pyrolysis. Biofuels and biorefineries, 2020, Singapore: Springer, 3-30 10.1007/978-981-15-2732-6_1

[94] Yang Z, Bai Z, Sun H, . Biomass pyrolysis liquid to citric acid via 2-step bioconversion. Microb Cell Fact, 2014, 13: 182.

[95] Yerrayya A, Natarajan U, Vinu R. Fang Z, Smith RL, Xu L. Production of valuable chemicals and fuel molecules from lignin via fast pyrolysis: experimental and theoretical studies using model compounds. Production of biofuels and chemicals with pyrolysis biofuels and biorefineries, 2020, Singapore: Springer, 77-111 10.1007/978-981-15-2732-6_9

[96] Zhang Q, Chang J, Wang T, Xu Y. Review of biomass pyrolysis oil properties and upgrading research. Energy Convers Manag, 2007, 48: 87-92.

[97] Zhang L, Liu R, Yin R, Mei Y. Upgrading of bio-oil from biomass fast pyrolysis in China: a review. Renew Sustain Energ Rev, 2013, 24: 66-72.

[98] Zhang S, Yang X, Zhang H, Chu C, Zheng K, Ju M. Liquefaction of biomass and upgrading of bio-oil: a review. Molecules, 2019, 24: 2250.

[99] Zhao X, Davis K, Brown R, Jarboe L, Wen Z. Alkaline treatment for detoxification of acetic acid-rich pyrolytic bio-oil for microalgae fermentation: effects of alkaline species and the detoxification mechanisms. Biomass Bioenergy, 2015, 80: 203-212.

[100] Zheng H, Wang X, Yomano LP, Shanmugam KT, Ingram LO. Increase in furfural tolerance in ethanologenic Escherichia coli LY180 by plasmid-based expression of thyA. Appl Environ Microbiol, 2012, 78: 4346-4352.

[101] Zheng D, Bao J, Lu J, Lv Q. Biodegradation of furfural by Bacillus subtilis strain DS3. J Environ Biol, 2015, 36: 727-732.

[102] Zheng A, Chen T, Sun J, Jiang L, Wu J, Zhao Z, Huang Z, Zhao K, Wei G, He F, Li H. Toward fast pyrolysis-based biorefinery: selective production of platform chemicals from biomass by organosolv fractionation coupled with fast pyrolysis. ACS Sustain Chem Eng, 2017, 8: 6507-6516.

[103] Zhuang XL, Zhang HX, Yang JZ, Qi HY. Preparation of levoglucosan by pyrolysis of cellulose and its citric acid fermentation. Bioresour Technol, 2001, 79: 63-66.

Funding

Korea Institute of Energy Technology Evaluation and Planning(20214000000500)

National Research Foundation of Korea(NRF-2020R1A5A1019631)