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| Author(s): |
Janaína Artem Ataide
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Ciências Médicas |
| Defense date: | 2018-07-13 |
| Examining board members: |
Priscila Gava Mazzola;
João Ernesto de Carvalho;
Marlus Chorilli
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| Advisor: | Priscila Gava Mazzola; Laura de Oliveira Nascimento |
| Abstract | |
Bromelain, a complex of substances extracted mainly from pineapple (Ananas comosus L.), has recognized properties such as anti-inflammatory, antithrombotic and fibrinolytic effects, antitumor activity and immunomodulatory effect, which has attracted attention for its use in skin care. However, bromelain is usually unstable under stress conditions, which results in a decrease of enzymatic activity and limits its pharmacological and industrial applications. Encapsulation of bromelain in nanoparticles can increase its stability, efficacy and safety, besides modification of its release kinetics. The natural polymer chitosan forms nanostructures that can entrap the enzyme, maintaining the claims of biocompatibility, biodegradability and natural source of the whole formulation. Therefore, the present work had as objective to encapsulate bromelain in chitosan nanoparticles in order to increase the stability of this enzymatic complex. For this, chitosan-bromelain nanoparticles were produced by ionic crosslinking, resulting in spherical particles with 100.9 ± 0.5 nm and polydispersity index of 0.222 ± 0.012. Encapsulation efficiency was 87.4% of total protein concentration, corresponding to 80.7% of enzymatic activity. However, chitosan-bromelain nanoparticles did not show the desired stability when stored in aqueous suspension, and were lyophilized. Glycine or maltose were used as lyoprotectants, resulting in an elegant product with a short reconstitution time, altering nanoparticles size and increasing the encapsulation rate when compared to the liquid form. In addition, this work also aimed to evaluate the activity and in vitro toxicity of the nanoparticles produced. For this, antioxidant and antiproliferative activity assays were conducted with free and nanoencapsulated bromelain. After nanoencapsulation process, bromelain maintained its antioxidant and antiproliferative activity, however, a greater time or concentration were required so the same effect could be observed, suggesting that bromelain was efficiently encapsulated and that its release kinetics may have been modified. Another activity test conducted was the in vitro scratch test with keratinocytes, in which nanoencapsulation of bromelain with chitosan was also effective in increasing wound retraction in in vitro scratch assay with keratinocytes when compared to free bromelain. Obtained results obtained allow us to conclude that bromelain was encapsulated in chitosan nanoparticles with satisfactory efficiency. The final formulation was lyophilized with the addition of glycine or maltose as lyoprotectants, resulting in enhanced bromelain encapsulation efficiency, as well as greater stability. After encapsulation, bromelain maintained its antioxidant and antiproliferative activity, being dependent on a higher concentration. In addition, nanoencapsulation increased its activity in wound retraction in in vitro scratch assay (AU) | |
| FAPESP's process: | 15/15068-5 - DEVELOPMENT OF POLYMERIC PARTICLES AS CARRIER SYSTEMS FOR BIOACTIVE PRODUCTS |
| Grantee: | Janaína Artem Ataide |
| Support Opportunities: | Scholarships in Brazil - Master |