Obtenção de compostos fenólicos da casca do barbatimão (Stryphnodendron adstringens (Mart.) Coville) empregando a extração assistida por ultrassom
Data
2022-02-23
Autores
Ribeiro, Maurício Masaru de Souza 
Orientadores
Veggi, Priscilla Carvalho
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Diversos estudos vêm demonstrando as capacidades medicinais e terapêuticas do barbatimão (Stryphnodendron adstringens (Mart.) Coville) e associando suas propriedades aos compostos fenólicos obtidos principalmente a partir de sua casca. Contudo, são escassos para o barbatimão estudos voltados a compreender a influência dos processos de extração e de seus parâmetros na obtenção de compostos bioativos. Dentro deste contexto, o presente estudo teve como objetivo empregar a extração assistida por ultrassom (UAE) e avaliar a influência dos parâmetros de processo no rendimento global (X0), nos teores de fenólicos totais (TPC), taninos totais (TTC), flavonoides totais (TFC) e na capacidade antioxidante redutor férrico (FRAP). Foram avaliados também a atividade antioxidante celular e a citotoxicidade dos extratos. Para tanto, foram estudados os parâmetros amplitude (0, 20, 30 e 40%), razão entre massa de matéria-prima (RM) por massa de solvente (S/F de 5, 10, 15, 20 e 25) e tempo de processo (2, 4, 6, 8, 10 e 12 min). As melhores condições de processo para a obtenção de compostos fenólicos da casca do barbatimão por UAE foram com a amplitude de 30%, S/F de 20 e tempo de 8 min, obtendo X0 de 43,39%, TPC de 385,40 mg ETA (ácido tânico equivalente)/g dry RM, TTC de 501,25 mg EP (pirogalol equivalente)/g dry RM, TFC de 243,33 mg EQ (quercetina equivalente)/g dry RM, e FRAP de 472,09 mg ET (trolox equivalente)/g dry RM. A UAE foi comparada às técnicas convencionais de extração por soxhlet e agitação mecânica (MA) que apresentou maiores rendimentos do que o soxhlet. A UAE e MA foram criteriosamente comparadas a fim de verificar os mecanismos envolvidos na UAE, demonstrando que a extração de taninos foi potencializada devido aos efeitos proporcionados pela sonda ultrassônica. O extrato obtido via UAE apresentou 66,67% de atividade antioxidante celular na concentração de extrato de 0,02 mg/mL, concentração na qual não foi apresentado citotoxicidade, apresentando um resultado comparável ao resveratrol e N-acetilcisteína e apresentou viabilidade celular superior a 80%. Estes resultados indicam que a técnica de UAE é uma alternativa viável às técnicas convencionais de extração para a obtenção de compostos fenólicos da casca do barbatimão.
Several studies have demonstrated the medicinal and therapeutic capabilities of barbatimão (Stryphnodendron adstringens (Mart.) Coville) and associated its properties with the phenolic compounds obtained mainly from its bark. However, studies aimed at understanding the influence of the extraction process and its parameters in obtaining bioactive compounds are scarce for this species. Within this context, the present study aimed to employ ultrasound-assisted extraction (UAE) and evaluate the influence of process parameters on global (X0), total phenolics (TPC), total tannins (TTC) and total flavonoids (TFC) yield, and ferric reducing antioxidant potential (FRAP). Cellular antioxidant activity and cytotoxicity of the extracts were also evaluated. Therefore, the parameters amplitude (0, 20, 30, and 40%), the ratio between sample mass by mass of solvent (S/F of 5, 10, 15, 20, and 25), and process time (2, 4, 6, 8, 10, and 12 min) were studied. The best process conditions for obtaining phenolic compounds from barbatimão bark by UAE were with an amplitude of 30%, S/F of 20 and time of 8 min, obtaining X0 of 43.39%, TPC of 385.40 mg ETA/g dry RM, TTC of 501.25 mg EP/g dry RM, TFC of 243.33 mg EQ/g dry RM, and FRAP of 472.09 mg ET/g dry RM. The UAE was also compared to conventional extraction techniques, soxhlet and mechanical agitation (MA), and showed higher yields than soxhlet. UAE and MA were carefully compared to verify the mechanisms involved in UAE, demonstrating that tannin extraction was potentiated due to the effects provided by the ultrasonic probe. The extract obtained by UAE showed 66.67% of cellular antioxidant activity at the extract concentration of 0.02 mg/mL, in which cytotoxicity was not presented, exhibiting a result comparable to resveratrol and N-acetylcysteine and showed cell viability higher than 80%. These results indicate that the UAE technique is a viable alternative to conventional extraction techniques to obtain phenolic compounds from barbatimão bark.
Several studies have demonstrated the medicinal and therapeutic capabilities of barbatimão (Stryphnodendron adstringens (Mart.) Coville) and associated its properties with the phenolic compounds obtained mainly from its bark. However, studies aimed at understanding the influence of the extraction process and its parameters in obtaining bioactive compounds are scarce for this species. Within this context, the present study aimed to employ ultrasound-assisted extraction (UAE) and evaluate the influence of process parameters on global (X0), total phenolics (TPC), total tannins (TTC) and total flavonoids (TFC) yield, and ferric reducing antioxidant potential (FRAP). Cellular antioxidant activity and cytotoxicity of the extracts were also evaluated. Therefore, the parameters amplitude (0, 20, 30, and 40%), the ratio between sample mass by mass of solvent (S/F of 5, 10, 15, 20, and 25), and process time (2, 4, 6, 8, 10, and 12 min) were studied. The best process conditions for obtaining phenolic compounds from barbatimão bark by UAE were with an amplitude of 30%, S/F of 20 and time of 8 min, obtaining X0 of 43.39%, TPC of 385.40 mg ETA/g dry RM, TTC of 501.25 mg EP/g dry RM, TFC of 243.33 mg EQ/g dry RM, and FRAP of 472.09 mg ET/g dry RM. The UAE was also compared to conventional extraction techniques, soxhlet and mechanical agitation (MA), and showed higher yields than soxhlet. UAE and MA were carefully compared to verify the mechanisms involved in UAE, demonstrating that tannin extraction was potentiated due to the effects provided by the ultrasonic probe. The extract obtained by UAE showed 66.67% of cellular antioxidant activity at the extract concentration of 0.02 mg/mL, in which cytotoxicity was not presented, exhibiting a result comparable to resveratrol and N-acetylcysteine and showed cell viability higher than 80%. These results indicate that the UAE technique is a viable alternative to conventional extraction techniques to obtain phenolic compounds from barbatimão bark.