resumo
Betulinic, oleanolic and ursolic acids are naturally occurring triterpenic acids that have attracted considerable interest due to their nutraceutical and pharmacological properties. These compounds can be extracted from natural sources, however, their simultaneous occurrence and very similar structures make their separation a challenging task. In this work we designed a simulated moving bed (SMB) unit for the separation of a representative natural extract containing betulinic, oleanolic and ursolic acids into high purity compounds using a two-step process: firstly, betulinic acid was isolated from oleanolic and ursolic acids, and secondly oleanolic and ursolic acids were fractionated. Preliminary HPLC experiments were conducted to select appropriate mobile and stationary phases. Equilibrium and mass transport parameters were determined through breakthrough experiments with pure compounds in a single column. Subsequently this information was successfully applied in the simulation of a ternary mixture separation, whose results were validated with ternary breakthrough measurements. Finally, the SMB was designed and optimized using a Design of Experiments approach combined with Response Surface Methodology (DoE-RSM), and simulated using a phenomenological rigorous model. It was concluded that using the designed SMB unit it is possible to produce betulinic, oleanolic and ursolic acids with purities of at least 99.4%, 99.1%, and 99.4% (all mass fraction), from a feed mixture containing 20%, 25%, and 55% of each acid, respectively.
palavras-chave
ULTRASOUND-ASSISTED EXTRACTION; SUPERCRITICAL-FLUID EXTRACTION; THIN-LAYER-CHROMATOGRAPHY; EUCALYPTUS-GLOBULUS BARK; TRITERPENIC ACIDS; NATURAL-PRODUCTS; ANTIINFLAMMATORY ACTIVITY; DRUG DISCOVERY; OUTER BARKS; DERIVATIVES
categoria
Engineering
autores
Aniceto, JPS; Azenha, IS; Domingues, FMJ; Mendes, A; Silva, CM
nossos autores
Carlos Manuel Silva
Professor associado
Ivo Samuel Caniceiro Azenha
Estudante de doutoramento
José P. S. Aniceto
Investigador Júnioragradecimentos
This work was developed in the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. Jose P.S. Aniceto thanks FCT for PhD grant SFRH/BD/91231/2012. Ivo S. Azenha thanks financial support of Project POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy - LEPABE funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). The authors would also like to thank Paralab, S.A. for providing the HPLC column and Monica Valega (University of Aveiro) for the valuable help in the setup of the HPLC unit.