(652c) Systematic Evaluation of Isoflavone Extraction from Soybean Meal

Resource sustainability concerns continue to increase as natural materials are used continuously without reclamation plans. Research efforts have been made toward finding sustainable chemical feedstocks to produce high-performance materials derived from biomass, with competitive economics and properties comparable to existing petroleum-based polymers [1]–[6]. The United States produces over 125 million metric tons of soybeans annually for animal feed, export, and human consumption [7]. Soybeans are rich in nutrients such as amino acids, proteins, and carbohydrates. There are also small quantities of underutilized chemicals, such as isoflavones, that can prove beneficial in the health and nutraceutical sector due to their anti-inflammatory and cancer inhibition effects in humans [8], [9]. Recent research progress has shown that isoflavones have been used to synthesize high-performance materials with high thermal stabilities [10], [11]. The extraction of isoflavone from soybean meal is a process that has been optimized at a lab-scale with little consideration for costs or the environment as they generally involve the usage of large quantities of hazardous organic solvents [12]–[14]. The commercialization of bio-based products can prove competitive against traditional petroleum-based products if the bio-based chemical extraction is designed to be economically viable and environmentally friendly at a larger scale. The isoflavone extraction methodology from soybean meal was represented as a mixed-integer non-linear programming (MINLP) problem. Alternative pathways were compared simultaneously using a superstructure-based approach and optimized in the General Algebraic Modeling Systems (GAMS) to determine the most economical path [15], [16]. The sustainable process index (SPI) was used to assess the environmental footprint of the recommended process. Each technology option is represented by mathematical models that include mass and energy balances, equipment design, and cost. We considered four essential stages of acquiring purified isoflavones from soybean meal, including pre-processing, extraction, acid hydrolysis, and purification.

Figure 1A displays the optimal pathway to extract and purify isoflavone from soybean meal at the commercial scale. The commercial-scale extraction of isoflavone from soybean meal presents a feasible solution by grinding (GRD), turbo-extraction (TE), filtration (FLT,1), drying (DRY,1), acid hydrolysis (AHY), neutralization (NT), filtration (FLT,2), organic solvent nanofiltration (OSN), and drying (DRY,2). The analysis of each model considered material and energy balances, utilities, design options, industrial constraints, and costs. Figure 1B and 1C presents a cost evaluation of the isoflavone extraction process under two scenarios with and without internal material recovery. The overall process cost can be minimized by reusing material when possible. By analyzing alternative options simultaneously, this study shows that commercial-scale extraction of soy isoflavones can be economically viable without detrimentally impacting the environment.

References

[1] E. D. Hernandez, A. W. Bassett, J. M. Sadler, J. J. La Scala, and J. F. Stanzione, “Synthesis and Characterization of Bio-based Epoxy Resins Derived from Vanillyl Alcohol,” ACS Sustain. Chem. Eng., vol. 4, no. 8, pp. 4328–4339, Aug. 2016, doi: 10.1021/acssuschemeng.6b00835.

[2] S. Curia et al., “Betulin-based thermoplastics and thermosets through sustainable and industrially viable approaches: new insights for the valorization of an underutilized resource,” ACS Sustain. Chem. Eng., Sep. 2019, doi: 10.1021/acssuschemeng.9b03471.

[3] E. A. Baroncini, “Bio-Based Thiol-ene Polymer Electrolytes,” Rowan University, NJ, 2019.

[4] A. W. Bassett et al., “Synthesis and characterization of molecularly hybrid bisphenols derived from lignin and CNSL: Application in thermosetting resins,” Eur. Polym. J., vol. 111, pp. 95–103, Feb. 2019, doi: 10.1016/j.eurpolymj.2018.12.015.

[5] J. R. Mauck et al., “Preparation and Characterization of Highly Bio-Based Epoxy Amine Thermosets Derived from Lignocellulosics,” Macromol. Chem. Phys., vol. 218, no. 14, p. 1700013, Jul. 2017, doi: 10.1002/macp.201700013.

[6] J. F. Stanzione III, J. M. Sadler, J. J. La Scala, K. H. Reno, and R. P. Wool, “Vanillin-based resin for use in composite applications,” Green Chem., vol. 14, no. 8, p. 2346, 2012, doi: 10.1039/c2gc35672d.

[7] National Agricultural Statistics Service (NASS), “Crop Production,” United States Department of Agriculture (USDA), 2018. Accessed: Oct. 04, 2019. [Online]. Available: https://www.nass.usda.gov/Publications/Todays_Reports/reports/crop0918.pdf.

[8] S. Joy et al., “The Isoflavone Equol Mediates Rapid Vascular Relaxation: Ca2+ -INDEPENDENT ACTIVATION OF ENDOTHELIAL NITRIC-OXIDE SYNTHASE/Hsp90 INVOLVING ERK1/2 AND Akt PHOSPHORYLATION IN HUMAN ENDOTHELIAL CELL,” J. Biol. Chem., vol. 281, no. 37, pp. 27335–27345, Sep. 2006, doi: 10.1074/jbc.M602803200.

[9] R. L. Birru et al., “The impact of equol-producing status in modifying the effect of soya isoflavones on risk factors for CHD: a systematic review of randomised controlled trials,” J. Nutr. Sci., vol. 5, 2016, doi: 10.1017/jns.2016.18.

[10] J. Dai et al., “High-Performing and Fire-Resistant Biobased Epoxy Resin from Renewable Sources,” ACS Sustain. Chem. Eng., vol. 6, no. 6, pp. 7589–7599, Jun. 2018, doi: 10.1021/acssuschemeng.8b00439.

[11] J. Dai, N. Teng, J. Liu, J. Feng, J. Zhu, and X. Liu, “Synthesis of bio-based fire-resistant epoxy without addition of flame retardant elements,” Compos. Part B Eng., vol. 179, p. 107523, Dec. 2019, doi: 10.1016/j.compositesb.2019.107523.

[12] L. Y. Yoshiara, T. B. Madeira, F. Delaroza, J. B. da Silva, and E. I. Ida, “Optimization of soy isoflavone extraction with different solvents using the simplex-centroid mixture design,” Int. J. Food Sci. Nutr., vol. 63, no. 8, pp. 978–986, Dec. 2012, doi: 10.3109/09637486.2012.690026.

[13] T. N. T. Tran et al., “Optimization of isoflavones extraction from soybeans using full factorial design,” J. Food Process. Preserv., vol. 43, no. 9, p. e14078, 2019, doi: 10.1111/jfpp.14078.

[14] S. H. Yuliani, M. R. Gani, E. P. Istyastono, and F. D. O. Riswanto, “Optimization of genistein and daidzein extraction,” J. Pharm. Pharmacogn. Res., vol. 4, pp. 231–241, 2018.

[15] J. Chea, A. Lehr, J. Stengel, M. J. Savelski, C. S. Slater, and K. Yenkie, “Evaluation of Solvent Recovery Options for Economic Feasibility through a Superstructure-Based Optimization Framework,” Ind. Eng. Chem. Res., Mar. 2020, doi: 10.1021/acs.iecr.9b06725.

[16] K. M. Yenkie, W. Wu, R. L. Clark, B. F. Pfleger, T. W. Root, and C. T. Maravelias, “A roadmap for the synthesis of separation networks for the recovery of bio-based chemicals: Matching biological and process feasibility,” Biotechnol. Adv., vol. 34, no. 8, pp. 1362–1383, Dec. 2016, doi: 10.1016/j.biotechadv.2016.10.003.