Skip to main content

Preparation of Thymus vulgaris Essential Oil Microcapsules by Complex Coacervation and Direct Emulsion: Synthesis, Characterization and Controlled Release Properties

Abstract

This study examines the preparation and characterization of Thymus vulgaris (L.) essential oil (TEO) microcapsules obtained by complex coacervation and direct emulsion techniques. The extraction yield of TEO for this study was 1.64% with Thymol (56.38%) and carvacrol (23.84%) as dominant components. The synthesis protocol was conducted with different polymer/polysaccharide mass ratios, essential oils quantities and cross-linking agent. Optical microscopy images of the microcapsules show spherical shape for particles of different diameters ranging from 5 to 50 μm. SEM analysis shows that the best results were obtained with a polymers ratio of 7%:8% and formaldehyde as cross-linking agent. The encapsulation yield is 65.67 and 98% for complex coacervation and direct emulsion, respectively. The encapsulation efficiency reveals that the amount of oxygenated monoterpenes encapsulated represents 78.34–74.31% of the total coated amount. Monoterpenes hydrocarbons represent 16.03–19.77%, followed by sesquiterpenes hydrocarbons at 3.7–4.2% for complex coacervation and direct emulsion, respectively. This result confirms that encapsulation efficiency can be related to the polarity of each TEO component. All results support the success of TEO encapsulation in terms of storage, protection and release, with lower thermal stability and faster TEO release kinetic for direct emulsion encapsulation. This result contrasts with complex coacervation, which provides a slower release profile and better thermal stability.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

References

  1. Manion, C.R.; Widder, R.M.: Essentials of essential oils. Am. J. Health Syst. Pharm. 74, e153–e162 (2017). https://doi.org/10.2146/ajhp151043

    Article  Google Scholar 

  2. Bakkali, F.; Averbeck, S.; Averbeck, D.; Idaomar, M.: Biological effects of essential oils. Food Chem. Toxicol. 46, 446–475 (2008). https://doi.org/10.1016/j.fct.2007.09.106

    Article  Google Scholar 

  3. Batish, D.R.; Singh, H.P.; Kohli, R.K.; Kaur, S.: Eucalyptus essential oil as a natural pesticide. For. Ecol. Manag. 256, 2166–2174 (2008). https://doi.org/10.1016/j.foreco.2008.08.008

    Article  Google Scholar 

  4. Satchell, A.C.; Saurajen, A.; Bell, C.; Barnetson, R.S.C.: Treatment of dandruff with 5% tea tree oil shampoo. J. Am. Acad. Dermatol. 47, 852–855 (2002). https://doi.org/10.1067/mjd.2002.122734

    Article  Google Scholar 

  5. Zhao, G.; Etherton, T.D.; Martin, K.R.; West, S.G.; Gillies, P.J.; Kris-Etherton, P.M.: Dietary α-linolenic acid reduces inflammatory and lipid cardiovascular risk factors in hypercholesterolemic men and women. J. Nutr. 134, 2991–2997 (2004). https://doi.org/10.1093/jn/134.11.2991

    Article  Google Scholar 

  6. Russo, M.; Suraci, F.; Postorino, S.; Serra, D.; Roccotelli, A.; Agosteo, G.E.: Essential oil chemical composition and antifungal effects on Sclerotium cepivorum of Thymus capitatus wild populations from Calabria, southern Italy. Braz. J. Pharmacogn. 23, 239–248 (2013). https://doi.org/10.1590/S0102-695X2013005000017

    Article  Google Scholar 

  7. Nabavi, S.M.; Marchese, A.; Izadi, M.; Curti, V.; Daglia, M.; Nabavi, S.F.: Plants belonging to the genus Thymus as antibacterial agents: from farm to pharmacy. Food Chem. 173, 339–347 (2015). https://doi.org/10.1016/j.foodchem.2014.10.042

    Article  Google Scholar 

  8. Hazzit, M.; Baaliouamer, A.; Veríssimo, A.R.; Faleiro, M.L.; Miguel, M.G.: Chemical composition and biological activities of Algerian Thymus oils. Food Chem. 116, 714–721 (2009). https://doi.org/10.1016/j.foodchem.2009.03.018

    Article  Google Scholar 

  9. Abdelli, W.; Bahri, F.; Romane, A.; Höferl, M.; Wanner, J.; Schmidt, E.; Jirovetz, L.: Chemical composition and anti-inflammatory activity of Algerian Thymus vulgaris essential oil. Nat. Prod. Commun. 12, 611–614 (2017). https://doi.org/10.1177/1934578x1701200435

    Article  Google Scholar 

  10. Cheurfa, M.; Allem, R.; Sebaihia, M.; Belhireche, S.: Effet de l’huile essentielle de Thymus vulgaris sur les bactéries pathogènes responsables de gastroentérites. Phytotherapie 11, 154–160 (2013). https://doi.org/10.1007/s10298-013-0777-7

    Article  Google Scholar 

  11. Helander, I.M.; Alakomi, H.L.; Latva-Kala, K.; Mattila-Sandholm, T.; Pol, I.; Smid, E.J.; Gorris, L.G.M.; Von Wright, A.: Characterization of the action of selected essential oil components on gram-negative bacteria. J. Agric. Food Chem. 46, 3590–3595 (1998). https://doi.org/10.1021/jf980154m

    Article  Google Scholar 

  12. Šegvić Klarić, M.; Kosalec, I.; Mastelić, J.; Piecková, E.; Pepeljnak, S.: Antifungal activity of thyme (Thymus vulgaris L.) essential oil and thymol against moulds from damp dwellings. Lett. Appl. Microbiol. 44, 36–42 (2007). https://doi.org/10.1111/j.1472-765X.2006.02032.x

    Article  Google Scholar 

  13. Lee, S.J.; Umano, K.; Shibamoto, T.; Lee, K.G.: Identification of volatile components in basil (Ocimum basilicum L.) and thyme leaves (Thymus vulgaris L.) and their antioxidant properties. Food Chem. 91, 131–137 (2005). https://doi.org/10.1016/j.foodchem.2004.05.056

    Article  Google Scholar 

  14. Schwarz, K.; Ernst, H.; Ternes, W.: Evaluation of antioxidative constituents from thyme. J. Sci. Food Agric. 70, 217–223 (1996). https://doi.org/10.1002/(sici)1097-0010(199602)70:2%3c217:aid-jsfa488%3e3.0.co;2-y

    Article  Google Scholar 

  15. Timilsena, Y.P.; Akanbi, T.O.; Khalid, N.; Adhikari, B.; Barrow, C.J.: Complex coacervation: principles, mechanisms and applications in microencapsulation. Int. J. Biol. Macromol. 121, 1276–1286 (2019). https://doi.org/10.1016/j.ijbiomac.2018.10.144

    Article  Google Scholar 

  16. Bezerra, F.M.; Carmona, O.G.; Carmona, C.G.; Lis, M.J.; de Moraes, F.F.: Controlled release of microencapsulated citronella essential oil on cotton and polyester matrices. Cellulose 23, 1459–1470 (2016). https://doi.org/10.1007/s10570-016-0882-5

    Article  Google Scholar 

  17. Solomon, B.; Sahle, F.F.; Gebre-Mariam, T.; Asres, K.; Neubert, R.H.H.: Microencapsulation of citronella oil for mosquito-repellent application: formulation and in vitro permeation studies. Eur. J. Pharm. Biopharm. 80, 61–66 (2012). https://doi.org/10.1016/j.ejpb.2011.08.003

    Article  Google Scholar 

  18. Bhandari, B.R.; D’Arcy, B.R.; Padukka, I.: Encapsulation of lemon oil by paste method using β-cyclodextrin: encapsulation efficiency and profile of oil volatiles. J. Agric. Food Chem. 47, 5194–5197 (1999). https://doi.org/10.1021/jf9902503

    Article  Google Scholar 

  19. de Fernandes, R.V.B.; Borges, S.V.; Botrel, D.A.: Influence of spray drying operating conditions on microencapsulated rosemary essential oil properties. Food Sci. Technol. 33, 171–178 (2013). https://doi.org/10.1590/S0101-20612013000500025

    Article  Google Scholar 

  20. Ocak, B.; Gülümser, G.; Baloğlu, E.: Microencapsulation of melaleuca alternifolia (tea tree) oil by using simple coacervation Method. J. Essent. Oil Res. 23, 58–65 (2011). https://doi.org/10.1080/10412905.2011.9700470

    Article  Google Scholar 

  21. Xiao, Z.; Liu, W.; Zhu, G.; Zhou, R.; Niu, Y.: Production and characterization of multinuclear microcapsules encapsulating lavender oil by complex coacervation. Flavour Fragr. J. 29, 166–172 (2014). https://doi.org/10.1002/ffj.3192

    Article  Google Scholar 

  22. Chung, S.K.; Seo, J.Y.; Lim, J.H.; Park, H.H.; Yea, M.J.; Park, H.J.: Microencapsulation of essential oil for insect repellent in food packaging system. J. Food Sci. 78, 1–6 (2013). https://doi.org/10.1111/1750-3841.12111

    Article  Google Scholar 

  23. Martin, A.; Varona, S.; Navarrete, A.; Cocero, M.J.: Encapsulation and co-precipitation processes with supercritical fluids: applications with essential oils. Open Chem. Eng. J. 4, 31–41 (2010). https://doi.org/10.2174/1874123101004020031

    Article  Google Scholar 

  24. Gouin, S.: Microencapsulation: industrial appraisal of existing technologies and trends. Trends Food Sci. Technol. 15, 330–347 (2004). https://doi.org/10.1016/j.tifs.2003.10.005

    Article  Google Scholar 

  25. Council of Europe: European directorate for qualite of medicine. In: European Pharmacopeia, 6th edn. Council of Europe, Strasbourg (2007)

  26. Ortega-Ramirez, L.A.; Silva-Espinoza, B.A.; Vargas-Arispuro, I.; Gonzalez-Aguilar, G.A.; Cruz-Valenzuela, M.R.; Nazzaro, F.; Ayala-Zavala, J.F.: Combination of Cymbopogon citratus with Allium cepa essential oils increased antibacterial activity in leafy vegetables. J. Sci. Food Agric. 97, 2166–2173 (2017). https://doi.org/10.1002/jsfa.8025

    Article  Google Scholar 

  27. Garcia-Sotelo, D.; Silva-Espinoza, B.; Perez-Tello, M.; Olivas, I.; Alvarez-Parrilla, E.; González-Aguilar, G.A.; Ayala-Zavala, J.F.: Antimicrobial activity and thermal stability of rosemary essential oil:β-cyclodextrin capsules applied in tomato juice. LWT 111, 837–845 (2019). https://doi.org/10.1016/j.lwt.2019.05.061

    Article  Google Scholar 

  28. Adams, R.P.: Identification of essential oil components by gas chromatograpy/mass spectrometry. Allured Publishing Corporation, Carol Stream (2007)

    Google Scholar 

  29. Davies, N.W.: Gas chromatographic retention indices of monoterpenes and sesquiterpenes on methyl silicon and Carbowax 20 M phases. J. Chromatogr. A 503, 1–24 (1990). https://doi.org/10.1016/S0021-9673(01)81487-4

    Article  Google Scholar 

  30. Wang, B.; Adhikari, B.; Barrow, C.J.: Optimisation of the microencapsulation of tuna oil in gelatin-sodium hexametaphosphate using complex coacervation. Food Chem. 158, 358–365 (2014). https://doi.org/10.1016/j.foodchem.2014.02.135

    Article  Google Scholar 

  31. Fernandes, R.V.D.B.; Borges, S.V.; Botrel, D.A.: Gum arabic/starch/maltodextrin/inulin as wall materials on the microencapsulation of rosemary essential oil. Carbohydr. Polym. 101, 524–532 (2014). https://doi.org/10.1016/j.carbpol.2013.09.083

    Article  Google Scholar 

  32. Stott, P.W.; Williams, A.C.; Barry, B.W.: Characterization of complex coacervates of some tricyclic antidepressants and evaluation of their potential for enhancing transdermal flux. J. Control Rel. 41, 215–227 (1996). https://doi.org/10.1016/0168-3659(96)01328-4

    Article  Google Scholar 

  33. Devi, N.; Hazarika, D.; Deka, C.; Kakati, D.K.: Study of complex coacervation of gelatin a and sodium alginate for microencapsulation of olive oil. J. Macromol. Sci. Part A Pure Appl. Chem. 49, 936–945 (2012). https://doi.org/10.1080/10601325.2012.722854

    Article  Google Scholar 

  34. Hosseini, S.F.; Zandi, M.; Rezaei, M.; Farahmandghavi, F.: Two-step method for encapsulation of oregano essential oil in chitosan nanoparticles: preparation, characterization and in vitro release study. Carbohydr. Polym. 95, 50–56 (2013). https://doi.org/10.1016/j.carbpol.2013.02.031

    Article  Google Scholar 

  35. Martins, I.M.; Rodrigues, S.N.; Barreiro, F.; Rodrigues, A.E.: Microencapsulation of thyme oil by coacervation. J. Microencapsul. 26, 667–675 (2009). https://doi.org/10.3109/02652040802646599

    Article  Google Scholar 

  36. Shukla, P.G.; Rajagopalan, N.; Sivaram, S.: Starch urea-formaldehyde matrix encapsulation. IV. Influence of solubility and physical state of encapsulant on rate and mechanism of release. J. Appl. Polym. Sci. 48, 1209–1222 (1993). https://doi.org/10.1002/app.1993.070480709

    Article  Google Scholar 

  37. Omidbaigi, R.; Kazemi, S.; Daneshfar, E.: Harvest time effecting on the essential oil content and compositions of Thymus vulgaris. J. Essent. Oil-Bearing Plants 11, 162–167 (2008). https://doi.org/10.1080/0972060X.2008.10643613

    Article  Google Scholar 

  38. Fani, M.; Kohanteb, J.: In vitro antimicrobial activity of Thymus vulgaris essential oil against major oral pathogens. J. Evidence-Based Complement. Altern. Med. 22, 660–666 (2017). https://doi.org/10.1177/2156587217700772

    Article  Google Scholar 

  39. Atti-Santos, A.C.; Pansera, M.R.; Paroul, N.; Atti-Serafini, L.; Moyna, P.: Seasonal variation of essential oil yield and composition of Thymus vulgaris L. (Lamiaceae) from South Brazil. J. Essent. Oil Res. 16, 294–295 (2004). https://doi.org/10.1080/10412905.2004.9698724

    Article  Google Scholar 

  40. Borugă, O.; Jianu, C.; Mişcă, C.; Goleţ, I.; Gruia, A.T.; Horhat, F.G.: Thymus vulgaris essential oil: chemical composition and antimicrobial activity. J. Med. Life 7(3), 56–60 (2014)

    Google Scholar 

  41. Zantar, S.; Garrouj, D.; Pagán, R.; Chabi, M.; Laglaoui, A.; Bakkali, M.; Zerrouk, M.: Effect of harvest time on yield, chemical composition, antimicrobial and antioxidant activities of Thymus vulgaris and Mentha pulegium essential oils. Eur. J. Med. Plants 8, 69–77 (2015). https://doi.org/10.9734/ejmp/2015/17513

    Article  Google Scholar 

  42. Benchabane, O.; Hazzit, M.; Mouhouche, F.; Baaliouamer, A.: Influence of extraction duration on the chemical composition and biological activities of essential oil of Thymus pallescens de Noé. Arab. J. Sci. Eng. 40, 1855–1865 (2015). https://doi.org/10.1007/s13369-015-1694-x

    Article  Google Scholar 

  43. Adrar, N.; Oukil, N.; Bedjou, F.: Antioxidant and antibacterial activities of Thymus numidicus and Salvia officinalis essential oils alone or in combination. Ind. Crops Prod. 88, 112–119 (2016). https://doi.org/10.1016/j.indcrop.2015.12.007

    Article  Google Scholar 

  44. Dob, T.; Dahmane, D.; Benabdelkader, T.; Chelghoum, C.: Studies on the essential oil composition and antimicrobial activity of Thymus algeriensis Boiss. et Reut. Int. J. Aromather. 16, 95–100 (2006). https://doi.org/10.1016/j.ijat.2006.04.003

    Article  Google Scholar 

  45. Perry, N.B.; Anderson, R.E.; Brennan, N.J.; Douglas, M.H.; Heaney, A.J.; McGimpsey, J.A.; Smallfield, B.M.: Essential oils from Dalmatian sage (Salvia officinalis L.): variations among individuals, plant parts, seasons, and sites. J. Agric. Food Chem. 47, 2048–2054 (1999). https://doi.org/10.1021/jf981170m

    Article  Google Scholar 

  46. Król, B.; Kołodziej, B.; Kędzia, B.; Hołderna-Kędzia, E.; Sugier, D.; Luchowska, K.: Date of harvesting affects yields and quality of Origanum vulgare ssp. hirtum (Link) Ietswaart. J. Sci. Food Agric. 99, 5432–5443 (2019). https://doi.org/10.1002/jsfa.9805

    Article  Google Scholar 

  47. Smallfield, B.M.; Van Klink, J.W.; Perry, N.B.; Dodds, K.G.: Coriander spice oil: effects of fruit crushing and distillation time on yield and composition. J. Agric. Food Chem. 49, 118–123 (2001). https://doi.org/10.1021/jf001024s

    Article  Google Scholar 

  48. Ghasemi Pirbalouti, A.; Hashemi, M.; Ghahfarokhi, F.T.: Essential oil and chemical compositions of wild and cultivated Thymus daenensis Celak and Thymus vulgaris L. Ind. Crops Prod. 48, 43–48 (2013). https://doi.org/10.1016/j.indcrop.2013.04.004

    Article  Google Scholar 

  49. Jordán, M.J.; Martínez, R.M.; Goodner, K.L.; Baldwin, E.A.; Sotomayor, J.A.: Seasonal variation of Thymus hyemalis Lange and Spanish Thymus vulgaris L. essential oils composition. Ind. Crops Prod. 24, 253–263 (2006). https://doi.org/10.1016/j.indcrop.2006.06.011

    Article  Google Scholar 

  50. Rota, M.C.; Herrera, A.; Martínez, R.M.; Sotomayor, J.A.; Jordán, M.J.: Antimicrobial activity and chemical composition of Thymus vulgaris, Thymus zygis and Thymus hyemalis essential oils. Food Control 19, 681–687 (2008). https://doi.org/10.1016/j.foodcont.2007.07.007

    Article  Google Scholar 

  51. Kowalski, R.; Wawrzykowski, J.: Essential oils analysis in dried materials and granulates obtained from Thymus vulgaris L., Salvia officinalis L., Mentha piperita L. and Chamomilla recutita L. Flavour Fragr. J. 24, 31–35 (2009). https://doi.org/10.1002/ffj.1914

    Article  Google Scholar 

  52. De Lisi, A.; Tedone, L.; Montesano, V.; Sarli, G.; Negro, D.: Chemical characterisation of Thymus populations belonging from Southern Italy. Food Chem. 125, 1284–1286 (2011). https://doi.org/10.1016/j.foodchem.2010.10.011

    Article  Google Scholar 

  53. Peng, C.; Zhao, S.Q.; Zhang, J.; Huang, G.Y.; Chen, L.Y.; Zhao, F.Y.: Chemical composition, antimicrobial property and microencapsulation of Mustard (Sinapis alba) seed essential oil by complex coacervation. Food Chem. 165, 560–568 (2014). https://doi.org/10.1016/j.foodchem.2014.05.126

    Article  Google Scholar 

  54. Crotts, G.; Park, T.G.: Preparation of porous and nonporous biodegradable polymeric hollow microspheres. J. Control Rel. 35, 91–105 (1995). https://doi.org/10.1016/0168-3659(95)00010-6

    Article  Google Scholar 

  55. Banerjee, S.; Chattopadhyay, P.; Ghosh, A.; Goyary, D.; Karmakar, S.; Veer, V.: Influence of process variables on essential oil microcapsule properties by carbohydrate polymer-protein blends. Carbohydr. Polym. 93, 691–697 (2013). https://doi.org/10.1016/j.carbpol.2013.01.028

    Article  Google Scholar 

  56. Ribeiro, A.J.; Neufeld, R.J.; Arnaud, P.; Chaumeil, J.C.: Microencapsulation of lipophilic drugs in chitosan-coated alginate microspheres. Int. J. Pharm. 187, 115–123 (1999). https://doi.org/10.1016/S0378-5173(99)00173-8

    Article  Google Scholar 

  57. Lertsutthiwong, P.; Noomun, K.; Jongaroonngamsang, N.; Rojsitthisak, P.; Nimmannit, U.: Preparation of alginate nanocapsules containing turmeric oil. Carbohydr. Polym. 74, 209–214 (2008). https://doi.org/10.1016/j.carbpol.2008.02.009

    Article  Google Scholar 

  58. Enascuta, C.E.; Stepan, E.; Oprescu, E.E.; Radu, A.; Alexandrescu, E.; Stoica, R.; Epure, D.G.; Niculescu, M.D.: Microencapsulation of essential oils. Rev. Chim. 69, 1612–1615 (2018). https://doi.org/10.37358/rc.18.7.6381

    Article  Google Scholar 

  59. El Miz, M.; Salhi, S.; Chraibi, I.; El Bachiri, A.; Fauconnier, M.-L.; Tahani, A.: Characterization and adsorption study of thymol on pillared bentonite. Open J. Phys. Chem. 04, 98–116 (2014). https://doi.org/10.4236/ojpc.2014.43013

    Article  Google Scholar 

  60. Nguemtchouin, M.M.G.; Ngassoum, M.B.; Ngamo, L.S.T.; Mapongmetsem, P.M.; Sieliechi, J.; Malaisse, F.; Lognay, G.C.; Haubruge, E.; Hance, T.: Adsorption of essential oil components of Xylopia aethiopica (Annonaceae) by kaolin from Wak, Adamawa province (Cameroon). Appl. Clay Sci. 44, 1–6 (2009). https://doi.org/10.1016/j.clay.2008.10.010

    Article  Google Scholar 

  61. Martins, I.M.; Rodrigues, S.N.; Barreiro, M.F.; Rodrigues, A.E.: Release of thyme oil from polylactide microcapsules. Ind. Eng. Chem. Res. 50, 13752–13761 (2011). https://doi.org/10.1021/ie200791r

    Article  Google Scholar 

  62. Mohamed, F.C.F.; van der, W.: PLGA microcapsules with novel dimpled surfaces for pulmonary delivery of DNA. Int. J. Pharm. 311, 97–107 (2006). https://doi.org/10.1016/j.ijpharm.2005.12.016

    Article  Google Scholar 

  63. Mayya, K.S.; Bhattacharyya, A.; Argillier, J.F.: Micro-encapsulation by complex coacervation: influence of surfactant. Polym. Int. 52, 644–647 (2003). https://doi.org/10.1002/pi.1125

    Article  Google Scholar 

  64. Park, S.J.; Shin, Y.S.; Lee, J.R.: Preparation and characterization of microcapsules containing lemon oil. J. Colloid Interface Sci. 241, 502–508 (2001). https://doi.org/10.1006/jcis.2001.7727

    Article  Google Scholar 

  65. Torini, L.; Argillier, J.F.; Zydowicz, N.: Interfacial polycondensation encapsulation in miniemulsion. Macromolecules 38, 3225–3236 (2005). https://doi.org/10.1021/ma047808e

    Article  Google Scholar 

  66. Fei, X.; Zhao, H.; Zhang, B.; Cao, L.; Yu, M.; Zhou, J.; Yu, L.: Microencapsulation mechanism and size control of fragrance microcapsules with melamine resin shell. Colloids Surf. A Physicochem. Eng. Asp. 469, 300–306 (2015). https://doi.org/10.1016/j.colsurfa.2015.01.033

    Article  Google Scholar 

  67. Yang, Z.; Peng, Z.; Li, J.; Li, S.; Kong, L.; Li, P.; Wang, Q.: Development and evaluation of novel flavour microcapsules containing vanilla oil using complex coacervation approach. Food Chem. 145, 272–277 (2014). https://doi.org/10.1016/j.foodchem.2013.08.074

    Article  Google Scholar 

  68. Al-Shannaq, R.; Farid, M.; Al-Muhtaseb, S.; Kurdi, J.: Emulsion stability and cross-linking of PMMA microcapsules containing phase change materials. Sol. Energy Mater. Sol. Cells 132, 311–318 (2015). https://doi.org/10.1016/j.solmat.2014.08.036

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Samira Chaib.

Supplementary Information

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Chaib, S., Benali, N., Arhab, R. et al. Preparation of Thymus vulgaris Essential Oil Microcapsules by Complex Coacervation and Direct Emulsion: Synthesis, Characterization and Controlled Release Properties. Arab J Sci Eng 46, 5429–5446 (2021). https://doi.org/10.1007/s13369-020-05223-w

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s13369-020-05223-w

Keywords

  • Thymus vulgaris
  • Essential oils
  • Encapsulation
  • Physical characterization
  • Release kinetics