Complex coacervation microcapsules by tannic acid crosslinking prolong the antifungal activity of cinnamaldehyde against Aspergillus brasiliensis

The antifungal activity and encapsulation properties of cinnamaldehyde-loaded microcapsules by tannic acid were investigated. The results showed that cinnamaldehyde exhibited a high in vitro antifungal effect against Aspergillus brasiliensis through altering the morphology of the hyphae, and its inhibition zone diameter (IZD) exceeded 15 mm with a minimum inhibitory concentration of 1.0 mg/mL. Cinnamaldehyde-loaded microcap-sules crosslinked with tannic acid have a high encapsulation efficiency (92.53 +/- 5.20%) and antifungal activity (37.82 +/- 0.63 mm), and the retention rate was 2.5 times of that of unencapsulated cinnamaldehyde after 30-d storage at 37 degrees C. Furthermore, the antifungal stability was enhanced (IZD 25.37 mm) after 60-d storage at 37 degrees C as compared with that of cinnamaldehyde (IZD 22.07 mm). The results of cell membrane integrity and the extracellular protein content also indicated that the microencapsulation could effectively protect cinnamalde-hyde, delay the decrease of antifungal effect and improve its long-term antifungal activity against A. brasiliensis by increasing the retention rate of cinnamaldehyde after storage.

Automated summary

The study investigated the antifungal activity and encapsulation properties of cinnamaldehyde-loaded microcapsules by tannic acid. The results showed that cinnamaldehyde had a high in vitro antifungal effect and the microencapsulation enhanced its stability and retention rate during storage, thus improving its long-term antifungal activity against A. brasiliensis.