## 4 Conclusions  
In this study, WPMD conjugates acted as an emulsifier, as well as a coating agent, in eugenol encapsulation. The concentration of eugenol and chitosan had an effect on the properties of the emulsions and spray-dried powders, including particle size, zeta potential, encapsulation efficiency, and loading capacity. The spray-dried powder prepared using an emulsion of 2.0% _w/w_ eugenol and 0.33% _w/w_ chitosan had the highest eugenol loading of 16.8%. The eugenol loading of this formulation with chitosan was twice as much as the loading obtained without chitosan reported previously. The eugenol encapsulation using chitosan as the second layer turned out to be effective at stabilizing the emulsion, as revealed by the zeta potential value. The presence of chitosan also improved the thermal stability and prevented the decomposition of the encapsulation product. The differences in eugenol concentration affected the release profile, whereas chitosan concentration had a role in slowing eugenol release. Generally, the results of the study indicate that the eugenol-loaded formulation yielded a biocompatible product with potential applications as food additives and pharmaceuticals.  
The following are available online at [[http://www.mdpi.com/2076-3417/10/9/3205/s1](http://www.mdpi.com/2076-3417/10/9/3205/s1)]([http://www.mdpi.com/2076-3417/10/9/3205/s1](http://www.mdpi.com/2076-3417/10/9/3205/s1)), Figure S1: Encapsulation efficiency and loading capacity of eugenol microcapsules loading with various concentration of eugenol, Figure S2: DSC thermogram of chitosan powder, Table S1: IR band WPMD conjugate, eugenol, and chitosan obtained from the FTIR measurement of the research, Table S2: IR band and % transmittance of F1 samples, Table S3: IR band and % transmittance of F2 samples.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Samples** & **n** & **k** & **R\({}^{2}\)** \\ \hline F1 powder-Chi 0.0\% & 0.2350 & 0.2061 & 0.8243 \\ F1 powder-Chi 0.067\% & 0.2061 & 0.3729 & 0.8379 \\ F1 powder-Chi 0.2\% & 0.1926 & 0.3204 & 0.8683 \\ F1 powder-Chi 0.33\% & 0.2479 & 0.2688 & 0.8538 \\ F2 powder-Chi 0.0\% & 0.2667 & 0.1756 & 0.8619 \\ F2 powder-Chi 0.067\% & 0.2519 & 0.1590 & 0.8696 \\ F2 powder-Chi 0.2\% & 0.2264 & 0.1756 & 0.8765 \\ F2 powder-Chi 0.33\% & 0.2263 & 0.1635 & 0.8720 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Kinetic data of eugenol released from microcapsules using the Korsmeyer–Peppas kinetic model.  
**Author Contributions:** Conceptualization, I.A., K.M. and M.N.; methodology, I.A. and K.M.; formal analysis, I.A.; investigation, I.A.; data curation, I.A. and K.M.; writing--original draft preparation, I.A.; writing--review and editing, I.A., K.M. and M.N.; visualization, I.A.; supervision, K.M. and M.N.; project administration, I.A. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received funding for the experimental work (2017-2020) and the APC (2020) from the Indonesian Agency for Agricultural Research and Development.  
**Acknowledgments:** The authors thank the Indonesia Agency for Agricultural Research and Development, Ministry of Agricultural and Universitas Indonesia for the research funding.  
**Conflicts of Interest:** The authors declare no conflict of interest.