Optimization of alkali-catalyzed organosolv treatment of spent coffee grounds for obtaining polysaccharides
Main Article Content
Abstract
The coffee industry is growing rapidly and generating increasing amounts of spent coffee grounds annually. Spent coffee grounds contain high levels of polysaccharide, which needs in-depth research to obtain and transform into value-added products. This study was carried out to optimize the alkali-catalyzed organosolv treatment of spent coffee grounds to enrich the polysaccharide content. A three-factor central composite design of the response surface model was used to optimize the treatment variables including reflux time, NaOH, and acetone concentration to yield the highest polysaccharide level. As a result, the maximum polysaccharide content was 73.13% obtained at a reflux time of 4.5 h, 62% acetone with 0.91% NaOH. The polysaccharide-rich material from spent coffee ground was composed of 39.37% mannan, 10.40% glucan, and 9.33% galactan. Partial removal of lignin and protein was observed during the treatment. Enzymatic hydrolysis of the spent coffee polysaccharides released the highest reducing sugars of 5583 mg/L using an enzyme cocktail containing 4% of cellulase and 1% of mannanase after 96 h. The enzymatic hydrolysate contained 3190 mg/L mannose and 1790 mg/L glucose, showing a feasible transformation of spent coffee polysaccharides.
Article Details
References
Asano, I., Hamaguchi, K., Fujii, S., & Iino, H. (2003). In vitro digestibility and fermentation of mannooligosaccharides from coffee mannan. Food Science and Technology Research 9(1), 62-66. https://doi.org/10.3136/fstr.9.62.
Ballesteros, L. F., Cerqueira, M. A., Teixeira, J. A., & Mussatto, S. I. (2015). Characterization of polysaccharides extracted from spent coffee grounds by alkali pretreatment. Carbohydrate Polymers127, 347-354. https://doi.org/10.1016/j.carbpol.2015.03.047.
Caetano, N. S., Silva, V. F., & Mata, T. M. (2012). Valorization of coffee grounds for biodiesel production. Chemical Engineering Transactions 26. http://dx.doi.org/10.3303/CET1226045.
Chen, H. T., O’hara, J. F., Azad, A. K., Taylor, A. J., Averitt, R. D., Shrekenhamer, D. B., & Padilla, W. J. (2008). Experimental demonstration of frequency-agile terahertz metamaterials. Nature Photonics 2(5), 295-298. http://dx.doi.org/10.1038/nphoton.2008.52.
Fiol, N., Escudero, C., & Villaescusa, I. (2008). Chromium sorption and Cr(VI) reduction to Cr(III) by grape stalks and yohimbe bark. Bioresource Technology 99(11), 5030-5036. https://doi.org/10.1016/j.biortech.2007.09.007.
Garlock, R. J., Balan, V., & Dale, B. E. (2012). Optimization of AFEX™ pretreatment conditions and enzyme mixtures to maximize sugar release from upland and lowland switchgrass. Bioresource Technology 104, 757-768. https://doi.org/10.1016/j.biortech.2011.11.034.
Gniechwitz, D., Reichardt, N., Blaut, M., Steinhart, H., & Bunzel, M. (2007). Dietary fiber from coffee beverage: degradation by human fecal microbiota. Journal of Agricultural and Food Chemistry 55(17), 6989-6996. https://doi.org/10.1021/jf070646b.
Harun, S., & Geok, S. K. (2016). Effect of sodium hydroxide pretreatment on rice straw composition. Indian Journal of Science and Technology 9(21), 1-9. https://dx.doi.org/10.17485/ijst/2016/v9i21/95245.
Jooste, T., García-Aparicio, M. P., Brienzo, M., van Zyl, W. H., & Görgens, J. F. (2013). Enzymatic hydrolysis of spent coffee ground. Applied Biochemistry and Biotechnology 169(8), 2248-2262. https://doi.org/10.1007/s12010-013-0134-1.
Liao, H., Li, S., Zheng, H., Wei, Z., Liu, D., Raza, W., Shen, Q., & Xu, Y. (2014). A new acidophilic thermostable endo-1,4-β-mannanase from Penicillium oxalicum GZ-2: Cloning, characterization and functional expression in Pichia pastoris. BMC Biotechnology 14, 90. http://dx.doi.org/10.1186/s12896-014-0090-z.
Miller, G. L. (1959). Use of dinitrosalicylic acid reagent for determination of reducing sugar. Analytical Chemistry 31(3), 426-428. https://doi.org/10.1021/ac60147a030.
Mussatto, S. I., Machado, E. M. S., Martins, S., & Teixeira, J. A. (2011). Production, composition, and application of coffee and its industrial residues. Food and Bioprocess Technology 4(5), 661-672. http://dx.doi.org/10.1007/s11947-011-0565-z.
Nguyen, A. Q., Cho E. J., Trinh T. P. L., Jeong J. S., & Bae H. J. (2017). Development of an integrated process to produce d-mannose and bioethanol from coffee residue waste. Bioresource Technology 244 (Part 1), 1039-1048. https://doi.org/10.1016/j.biortech.2017.07.169.
Preethu, D., Bhanu Prakash, B., Srinivasamurthy, C., & Vasanthi, B. (2007). Composting and co composting of coffee husk and pulp with source-separated municipal solid waste: a breakthrough in valorization of coffee waste. In Joseph, K., Nagendran, R., & Thanasekaran, K. (Eds.), Proceedings of International Conference on Sustainable Solid Waste Management (270-275). Chennai, India: Centre for Environmental Studies, Department of Civil Engineering, Anna University.
Roy, R., Rahman, M. S., & Raynie, D. E. (2020). Recent advances of greener pretreatment technologies of lignocellulose. Current Research in Green and Sustainable Chemistry 3, 100035. https://doi.org/10.1016/j.crgsc.2020.100035.
Simões, J., Madureira, P., Nunes, F. M., do Rosário Domingues, M., Vilanova, M., & Coimbra, M. A. (2009). Immunostimulatory properties of coffee mannans. Molecular Nutrition and Food Research 53(8), 1036-1043. https://doi.org/10.1002/mnfr.200800385.
Sluiter, A., Hames, B., Ruiz, R., Scarlata, C., Sluiter, J., Templeton, D., & Crocker, D. (2008). Determination of structural carbohydrates and lignin in biomass. Laboratory Analytical Procedure 1617, 1-16.
Tang, S., Cao, Y., Xu, C., Wu, Y., Li, L., Ye, P., Luo, Y., Gao, Y., Liao, Y., Yan, Q., & Cheng, X. (2020). One-step or two-step acid/alkaline pretreatments to improve enzymatic hydrolysis and sugar recovery from Arundo Donax L. Energies 13(4), 948. https://doi.org/10.3390/en13040948.
Trinh, L. T. P., Nguyen, T. V., Nguyen, A. T. V., & Nguyen, A. Q. (2022). Two-step pretreatment for improving enzymatic hydrolysis of spent coffee grounds. The Journal of Agriculture and Development 21(3), 44-52. https://doi.org/10.52997/jad.6.03.2022.
Trinh, L. T. P., Choi, Y.-S., & Bae, H. J. (2018). Production of phenolic compounds and biosugars from flower resources via several extraction processes. Industrial Crops and Products 125, 261-268. https://doi.org/10.1016/j.indcrop.2018.09.008.
VS (Vietnam Standards). (2015). Standard No. TCVN 10791:2015 dated on June 17, 2015. Malt - Determination of the nitrogen content and calculation of the crude protein content - Kjeldahl method. Retrieved May 20, 2023, from https://tieuchuan.vsqi.gov.vn/tieuchuan/view?sohieu=TCVN+10791%3A2015.
VS (Vietnam Standards). (2009). Standard No. TCVN 8124:2009 (ISO 2171:2007) dated on January 01, 2009. Cereals, pulses and byproducts - Determination of ash yield by incineration. Retrieved July 15, 2023, from https://tieuchuan.vsqi.gov.vn/tieuchuan/view?sohieu=TCVN+8124%3A2009.
Yin, X., Wei, L., Pan, X., Liu, C., Jiang, J., & Wang, K. (2021). The pretreatment of Lignocelluloses with green solvent as biorefinery preprocess: A minor review. Frontiers in Plant Science 12, 670061. https://doi.org/10.3389/fpls.2021.670061.