Particle size and root diameter effects on the extraction of glycyrrhizic acid from licorice using ultrasonic: Full factorial experimental design and response surface methodology

Document Type : Full Research Paper

Author

• Zarrin Nasri

https://doi.org/10.22067/ifstrj.2021.67074.0

Abstract

Introduction: Licorice is one of the most important medicinal plants in the world. This plant has been used in the world for more than 2000 years and is applied in various industries including pharmaceutical, food and tobacco industries. Iran is one of the best regions in the world in terms of medicinal plants. The roots of the licorice plant are widely used in the food and pharmaceutical industries. These roots are strong natural sweeteners, about 50-170 times sweeter than sucrose. The value of this plant is related to its chemical components. Glycyrrhizin is the most abundant component of this plant and is present in licorice in the form of potassium or calcium salt of glycyrrhizic acid and is considered as an indicator of licorice quality. In recent years, novel extraction methods with different energy sources have been proposed for improving extraction efficiency. Higher extraction efficiencies can be achieved by using microwave, ultrasonic and high pressure methods. In the ultrasonic extraction method, the extraction rate increases due to the presence of cavitation. The cavities formed in the solvent grow and then collapse rapidly, releasing a large amount of energy that increases the local temperature and pressure. Therefore, the solvent penetrates more into the plant cell material and the contents of the plant cells are released into the solvent medium. Also, physical effects such as liquid circulation and turbulence produced by cavitation help to increase the contact surface between the solvent and the plant particles and lead to more solvent penetration into the plant matrix.
 
Materials and Methods: The aim of this study is to statistically investigate the effect of particle size and licorice root diameter on the rate of glycyrrhizic acid extraction using ultrasonic. The full factorial experimental design method and response surface methodology have been used to determine the levels of the parameters and to model the responses, respectively. Independent variables included particle size of licorice root at three levels (35-60, 60-120, ≥ 120 mesh) and licorice root diameter is at three levels (1-2, 2-3, ≥3 cm). Total extract and glycyrrhizinic acid yield are considered as response variables. The solvent used was ammonia and the analysis of glycyrrhizic acid in the extract was performed by HPLC method. The licorice root used in this research was from Bojnourd region. Monoammonium glycyrrhizic acid (99.5%) was purchased as an HPLC standard from Sigma and ammonia from Merck. The method of glycyrrhizic acid extraction from licorice root was based on the British Pharmacopoeia method in this research.
 
Result and Discussion: The results showed that regarding the response glycyrrhizic acid yield, the parameter licorice root diameter had a significant effect on the response, but the particle size parameter had no significant effect. Also, two parameters had interaction. Based on the modeling results of the extraction process, the optimal conditions for obtaining the maximum total extract of licorice root included particle size, 125 μm (120 mesh) and licorice root diameter, 3.28 cm, which leaded to 68.16 wt% total extract. The optimal response conditions for glycyrrhizic acid yield from licorice root included particle size, (120 mesh) and licorice root diameter, 2.72 cm, which leaded to the extraction of 6.02 wt%glycyrrhizic acid from the root. Also, a comparison was performed between glycyrrhizic acid extraction from licorice in ultrasonic bath and ultrasonic probe. The results showed that the amount of glycyrrhizic acid extraction 
was similar and was equal to 5.5 wt%. The effect of particle size distribution has also been investigated. According to the results in ultrasonic extraction, particle size distribution had a positive effect on extraction.According to the results of this research, the parameter of licorice root diameter had a significant effect on the response of glycyrrhizic acid yield and with decreasing licorice root diameter, the amount of glycyrrhizic acid extraction increased. Also, the efficiency obtained by extraction method in ultrasonic bath is compared with ultrasonic probe. It can be concluded that glycyrrhizic acid extraction from licorice with using ultrasonic is an effective method for extraction

Keywords

• Licorice
• Ultrasonic
• Glycyrrhizic acid
• Response Surface Methodology

References

1. Ahmadi Hosseini, S. M., Souri, M.K., Farhadi, N., Moghaddam, M., Omidbaigi, R. (2014). Changes in glycyrrhizin content of Iranian licorice (Glycyrrhiza glabra L.) affected by different root diameter and ecological conditions. Agrcultural Communications, 2(4), 27-33.
2. Ahmadian, H., Mirahmadi, F., Rashidzadeh, B., (2018). Effects of ultrasound on extraction of glycyrrhizin from Glycyrrhiza glabra L. in comparison with modified Rosen's method. Iranian Journal of Medicinal and Aromatic Plants. 33(6), 961-974. (In Persian). DOI: 22092/IJMAPR.2018.108293.1885
3. Bolouri Moghaddam, E., Hemmati, Kh., Bashirisadr, Z., and Mashayekhi, K. (2009). Effect of harvest time and root diameter on Glycyrrhizin content in Glycyrrhiza glabra. Journal of Plant Production, 16(2), 29-45. (in Persian)
4. British Pharmacopoeia, (2009). Medicines and Healthcare products Regulatory Agency,
5. Charpe, T.W., Rathod, V.K. (2012). Extraction of glycyrrhizic acid from licorice root using ultrasound: Process intensification studies. Chemical Engineering and Processing, 54, 37– 41. https://doi.org/10.1016/j.cep.2012.01.002
6. Charpe, T.W., Rathod, V.K. (2014). Effect of ethanol concentration in ultrasound assisted extraction of glycyrrhizic acid from licorice root, Iranian Journal of Chemical Engineering, 11(4), 21-30.
7. Douglas, J.A., Douglas, M. H., Lauren, D. R., Martin, R. J., Deo, B., Follett, J. M.,  Jensen, D. J. (2004).  Effect of plant density and depth of harvest on the production and quality of licorice (Glycyrrhiza glabra) root harvested over 3 years, New Zealand Journal of Crop and Horticultural Science, 32, 363-373. https://doi.org/10.1080/01140671.2004.9514317
8. Hemati, Kh., Hemati, N., Ghaedi, A., (2015). The effect of habtat, root diameter, and type of tissue on some secondary metabolites content of licorice (glycerrhiza glabra) in Khorasan Razavi (Ghoochan), Journal of Plant Evvironmental Physiology, 10(3) 1-10. (In Persian).
9. Hennell, J. R., Lee, S., Khoo, C. S., Gray, M. J., Bensoussan, A. (2008). The determination of glycyrrhizic acid in Glycyrrhiza uralensis Fisch. ExDC. (Zhi Gan Cao) root and the dried aqueous extract by LC– DAD, Journal of Pharmaceutical and Biomedical Analysis. 47, 494-500. https://doi.org/10.1016/j.jpba.2008.01.037
10. Keyhani, V., Mortazavi, S.A., Karimi, M., Karazhiyan, H., Sheikholeslami, Z., (2016). Ultrasound-assisted extraction of saponins from chubak plant (Acanthophyllum Glandulosum) root based on their emulsification and foaming properties, Research and Innovation in Food Science and Technology, 4(4), 325-342. (in Persian). DOI:22101/JRIFST.2016.01.30.444
11. Khanahmadi, M., Gaffarzadegan, R., Khalighi-Sigaroodi, F., Naghdi Badi, H., Mehrafarin, A., Hajiaghaee, R. (2018). Optimization of the glycyrrhizic acid extraction from licorice by response surface methodology, Iranian Journal of Chemistry and Chemal Enineering, 37 (1), 121-129 .
12. Liao, J., Qu, B., Zheng, N., (2016). Extraction of glycyrrhizic acid from glycyrrhiza uralensis using ultrasound and Its process extraction model, Applied Sciences, https://doi.org/10.3390/app6110319
13. Mareshige, K., Hayashi, S., Shibata, T., Yamamoto, Y., Sekizaki, H. (2011). Variation of glycyrrhizin and liquiritin contents within a population of 5-year-old licorice (Glycyrrhiza uralensis) plants cultivated under the same conditions, Biological and Pharmaceutical Bulletin. 34, 1334-1337. https://doi.org/10.1248/bpb.34.1334
14. Ming, O. S. (2007). Comparative study on optimization of continuous countercurrent extraction for licorice (MSc thesis), Department of Pharmacy. National University of Singapore, Singapore.
15. Mukhopadhyay, M., Panja, P., (2008). A novel process for extraction of natural sweetener from licorice (Glycyrrhiza glabra) roots. Separation and Purification Technology, 63, 539–545. https://doi.org/10.1016/j.seppur.2008.06.013
16. Noori, W. O., Waisi, B.I, Alhassani, M.H. (2018). Extraction of glycyrrhizin from licorice (Glycyrrhiza Glabra L.) by bulk liquid membrane. Environmental Technology & Innovation 12, 180–188. https://doi.org/10.1016/j.eti.2018.08.010
17. Pan, X., Liu, H., Jia, G., and Shu, Y. Y. (2000). Microwave-assisted extraction of glycyrrhizic acid from licorice Biochemical Engineering Journal, 5, 173–177. https://doi.org/10.1016/S1369-703X(00)00057-7
18. Shabkhiz, M.A., Eikani, M.H., Golmohammad, F., Bashiri Sadr, Z., (2015). Optimized Pressurized hot water extraction of glycyrrhizic acid from Licorice roots, Innovative Food Technologies, 2(4), 11-21. (In Persian). DOI:22104/JIFT.2015.200
19. Usai, M., Vincenzo, P., Domenico, A. (1995). Glycyrrhizin variability in subterranean organs of Sardinian Glycyrrhiza glabra subspecies glabra var. glabra. Journal of Natural Products, 58, 1727-1729. https://doi.org/10.1021/np50125a013

Yeop, A., Sandanasamy, J., Pang, S. F., Abdullah, S., Yusoff, M.M., Gimbun, J. (2017).The effect of particle size and solvent type on the gallic acid yield obtained from Labisia pumila by ultrasonic extraction, MATEC Web of Conferences 111, 02008 (2017) FluidsChE 2017, https://doi.org/10.1051/matecconf/201711102008