Self-aggregating properties of inulin in a dilute solution

The creation of functional food products based on inulin-containing vegetable raw materials can provide the population with functional diabetic nutrition. In this regard, investigation of the technological parameters of obtaining inulin from Jerusalem artichoke tubers (Helianthus tuberosus L.) and determination of its quantitative characteristics seem highly relevant. This study aims to determine the qualitative characteristics of inulin obtained from Jerusalem artichoke tubers by both flash extraction and conventional methods. Jerusalem artichoke inulin samples were obtained by the flash extraction method at a high temperature of 105 °C during both shorter and longer periods of time and by the conventional method at a temperature of 75 °C in a neutral medium. The hydrodynamic properties and molecular weight of the samples demonstrated the self-aggregating properties of this biopolymer. Inulin obtained by the flash extraction method consists of two fractions: low-molecular weight inulin and high-molecular weight aggregate represented by a polysaccharide complex. These aggregates can be formed both by inter- and intramolecular interactions of various inulin fractions in the solution. As expected, their isolation using conventional methods appeared impossible: the method of concentration yielded a number of subfractions on the UV membrane and a large amount of aggregated water-insoluble microgel. At the same time, inulin obtained by the conventional method consists of one fraction, although having a high degree of polydispersity. In order to obtain high-quality inulin intended for nutritional and prophylactic purposes, it is preferable to use the flash extraction method over short periods of time.

1. Anderson-Dekkers I., Nouwens-Roest M., Brigitte P., Vaughan E. Inulin. In: Handbook of Hydrocolloids. Third ed. Chapter 17. Amsterdam: Woodhead Publishing Series in Food Science, Technology and Nutrition; 2021, p. 537-562. https://doi.org/10. 1016/B978-0-12-820104-6.00015-2.

2. Kontogiorgos V. Stabilisers. Inulin. In: Encyclopedia of Dairy Sciences. Third ed. NY: Academic Press; 2022, vol. 2, p. 689-694. https://doi.org/10.10 16/B978-0-12-818766-1.00321-4.

3. BeMiller J. N. Inulin and Konjac Glucomannan. In: Carbohydrate Chemistry for Food Scientists. Amsterdam: Elsevier Inc., AACC International; 2019, p. 253-259. https://doi.org/10.1016/B978-0- 12-812069-9.00010-8.

4. Kozhukhova M. A., Nazarenko M. N., Barkhatova T. V., Khripko I. A. Obtaining and identification of inulin from Jerusalem artichoke (Helianthus tuberosus) tubers. Foods and Raw Materials. 2015;3(2):13-22. https://doi.org/10.12737/13115.

5. Chiavaro E., Vittadini E., Corradini C. Physicochemical characterization and stability of inulin gels. European Food Research and Technology. 2007; 225:85-94. https://doi.org/10.1007/s00217-006-0385-y.

6. Mensink M. A., Frijlink H. W., van der Voort Maarschalk K., Hinrichs W. L. J. Inulin, a flexible oligosaccharide I: Review of its physicochemical characteristics. Carbohydrate Polymers. 2015;130:405-419. https://doi.org/10.1016/j.carbpol.2015.05.026.

7. Mudgil D., Barak S. Classification, Technological Properties, and Sustainable Sources. In: Dietary Fiber: Properties, Recovery, and Applications. Chapter 2. NY: Academic Press; 2019, p. 27-58. https://doi.org/ 10.1016/B978-0-12-816495-2.00002-2.

8. Manukyan L. S., Kochikyan V. T., Andreasyan N. A., Afyan K. B., Balayan A. M. Isolation of inulin from various plant materials. Biologicheskii zhurnal Armenii. 2014;(4):71-75. (In Russian).

9. Ma X. Y., Zhang L. H., Shao H. B., Xu G., Zhang F., Ni F. T., et al. Jerusalem artichoke (Helianthus tuberosus), a medicinal salt-resistant plant has high adaptability and multiple-use values. Journal of Medicinal Plants Research. 2011;5(8):1272-1279.

10. Ashurov A. I., Dzhonmurodov A. S., Mukhidinov Z. K., Usmanova S. R., Partoev K. The intensification of the process for the polysaccharides extraction from Jerusalem artichoke. Vestnik Tadzhikskogo natsional'nogo universiteta. Seriya estestvennykh nauk = Bulletin of the Tajik National University. Series of natural sciences. 2019;3:208- 214. (In Russian).

11. Shoaib M., Shehzada A., Omarc M., Rakha A., Raza H., Sharif H. R., et al. Inulin: properties, health benefits, and food applications. Carbohydrate Polymers. 2016;147:444-454. https://doi.org/10.1016/j. carbpol.2016.04.020.

12. Colwell J. A. Type II diabetes, pre-diabetes, and the metabolic syndrome. The Journal of the American Medical Association. 2011;306(2):215- 238. https://doi.org/10.1001/jama.2011.970.

13. Jackson P. P. J., Wijeyesekera A., Theis S., Harsselaar J., Rastall R. A. Food for thought! Inulintype fructans: does the food matrix matter? Journal of Functional Foods. 2022;90:104987. https://doi. org/10.1016/j.jff.2022.104987.

14. Shanenko E. F., Silaeva M. A., Ermolaeva G. A. Jerusalem artichoke – raw materials for preventive nutrition. Voprosy pitaniya = Problems of Nutrition. 2016;85(S2):219. (In Russian).

15. Amjadi S., Almasi H., Hamishehkar H., Khaledabad M. A., Lim L.-T. Cationic inulin as a new surface decoration hydrocolloid for improving the stability of liposomal nanocarriers. Colloids and Surfaces B: Biointerfaces. 2022;213:112401. https://doi. org/10.1016/j.colsurfb.2022.112401.

16. Franck A. Technological functionality of inulin and oligofructose. British Journal of Nutrition. 2002;87 (S2):287-291. https://doi.org/10.1079/BJN/2002550.

17. Barclay T., Ginic-Markovic M., Cooper P., Petrovsky N. Inulin – a versatile polysaccharide with multiple pharmaceutical and food chemical uses. Journal of Excipients and Food Chemicals. 2010;1(3):27-50.

18. Ronkart S. N., Deroanne C., Paquot M., Fougnies C., Blecker C. S. Impact of the crystallization pathway of inulin on its mono-hydrate to hemihydrate thermal transition. Food Chemistry. 2010; 119(1):317-322. https://doi.org/10.1016/j.foodchem. 2009.06.035.

19. Dan A., Ghosh S., Moulik S. P. Physicochemical studies on the biopolymer inulin: a critical evaluation of its self-aggregation, aggregationmorphology, interaction with water, and thermal stability. Biopolymers. 2009;91(9):687-699. https://doi. org/:10.1002/bip.21199.

20. Muhidinov Z. K., Teshaev Kh., Jonmurodov A., Khalikov D., Fishman M. Physico-chemical characterization of pectic polysaccharides from various sources obtained by steam assisted flash extraction (SAFE). Macromolecular Symposia. 2012;317-318(1):142-148. https://doi.org/10.1002/masy.201100108.

21. Muhidinov Z. K., Bobokalonov J. T., Ismoilov I. B., Strahan G. D., Chau H. K., Hotchkiss A. T., et al. Characterization of two types of polysaccharides from Eremurus hissaricus roots growing in Tajikistan. Food Hydrocolloids. 2020;105:105768. https:// doi.org/10.1016/j.foodhyd.2020.105768.

22. Li W., Zhang J., Yu C., Li Q., Dong F., Wang G., et al. Extraction, degree of polymerization determination and prebiotic effect evaluation of inulin from Jerusalem artichoke. Carbohydrate Polymers. 2015;121:315-319. https://doi.org/10.1016/j.carbpol.2014.12.055.

23. Lo ́pez-Molina D., Navarro-Mart ́ınez M. D., Melgarejo F. R., Hiner A. N. P., Chazarra S., Rodríguez-López J. N. Molecular properties and prebiotic effect of inulin obtained from artichoke (Cynara scolymus L.). Phytochemistry. 2005;66 (12):1476-1484. https://doi.org/10.1016/j.phytochem. 2005. 04.003.

24. Kitamura S., Hirano T., Takeo K., Mimura M., Kajiwara K., Stokke B. T., et al. Conformation of (2→1)-β-d-fructan in aqueous solution. International Journal of Biological Macromolecules. 1994;16(6):313- 317. https://doi.org/10.1016/0141-8130(94)90062-0.

25. Wolff D., Czapla S., Heyer A. G., Radosta S., Mischnick P., Springer J. Globular shape of high molar mass inulin revealed by static light scattering and viscometry. Polymer. 2000;41(22):8009-8016. https://doi.org/10.1016/S0032-3861(00)00168-3.

26. Podzimek S. Light scattering, size exclusion chromatography and asymmetric flow field flow fractionation powerful tools for the characterization of polymers, protein and nanoparticles. New Jersey: Hoboken Publisher; 2011, p. 333. https://doi.org/ 10.1002/9780470877975.

27. French A. D. Accessible conformations of the B-D-(2–1)-and-(2–6)-linked D-fructans inulin and levan. Carbohydrate Research. 1988;176(1):17-30.

28. Vereyken I. J., van Kuik J. A., Evers T. H., Rijken P. J., de Kruijff B. Structural requirements of the fructan–lipid interaction. Biophysical Journal. 2003;84(5):3147-3154. https://doi.org/10.1016/s0006- 3495(03)70039-3.

29. Timmermans J. W., Slaghek T. M., Iizuka M., Van den Ende W., De Roover J., van Laere A. Isolation and structural analysis of new fructans produced by chicory. Journal of Carbohydrate Chemistry. 2001; 20(5):375-395. https://doi.org/10.1081/CAR-100105711