Integrated utilization of guava (Psidium guajava L.): antioxidant activity of phenolic extracts obtained from guava seeds with supercritical CO2-ethanol

Abstract

Neste trabalho, explorou-se a possibilidade de obter extratos fenólicos com atividade antioxidante (AA) a partir de sementes de goiaba Colombiana (Psidium guajava L.) usando dióxido de carbono supercrítico adicionado com etanol como cosolvente (SC CO 2 /EtOH). Extratos brutos foram obtidos através de planejamentos de etapas de extração em função da pressão (10, 15 e 20 MPa) e temperatura (313, 323 e 333 K) (com quatro diferentes planejamentos de etapas de extração). Em cada um dos extratos, determinou-se o conteúdo de fenólico total (TPC) e AA (métodos de clareamento do β-caroteno e DPPH (2,2-difenil-1-picrilhidrazila) de eliminação). Este trabalho permitiu obter um extrato fenólico mais eficaz, com atividade antioxidante mais potente comparada com outros trabalhos. O extrato mais ativo foi fracionado utilizando coluna cromatográfica rápida (FCC), cujo processo foi monitorado por coluna cromatográfica de camada fina (TLC), sendo obtidas quatro frações. A fração mais ativa e o melhor extrato bruto foram testados como antioxidantes de óleos vegetais (as variáveis de resposta foram valor de peróxido (PV) e dieno conjugados (CD)). Observou-se que a fração IV teve um bom desempenho na prevenção da formação de peróxidos, enquanto que o melhor extrato bruto inibiu a degradação de dienos conjugados. Semente de goiaba é uma promissora fonte de antioxidantes que podem ser extraídos usando SC CO 2 /EtOH a partir de planejamento especial de etapas de extração, estes compostos podem ser utilizados como conservantes em alimentos como óleos.In this work, it was explored the possibility of obtaining phenolic extracts with antioxidant activity (AA) from Colombian guava seeds (Psidium guajava L.) using supercritical carbon dioxide adding ethanol as cosolvent (SC CO 2 /EtOH). The crude extracts were obtained by block extraction designs step to step (four steps) as function of pressure (10, 15 and 20 MPa) and temperature (313, 323 and 333 K) (with four different extraction step designs). In each one of the extracts, the total phenolic content (TPC) and AA were determined (β-carotene bleaching and scavenging DPPH (2,2-diphenyl-1-picrylhydrazyl) methods). This work allowed to obtain a most effective phenolic extract, that presented a most potent antioxidant activity compared toward previous works. The most active extract was subjected to flash chromatography column (FCC), whose process was monitored by thin layer chromatography (TLC), being obtained four fractions. The most active fraction and the best crude extract were tested as potential antioxidant in edible oil (the response variables were the peroxide value (PV) and the conjugated dienes (CD)). It was observed that the fraction IV showed a good performance in preventing the formation of peroxides, while the best crude extract inhibited the degradation of conjugated dienes. The guava seeds are a promising source of antioxidants which can be extracted using SC CO 2 /EtOH by special extraction step design, these compounds can be used as preservatives in foods such as edible oils....

Valorization of agroindustrial wastes: Identification by LC‐MS and NMR of benzylglucosinolate from papaya (Carica papaya L.) seeds, a protective agent against lipid oxidation in edible oils

“…The protective effect against lipid oxidation or antioxidant activity (AA) of crude extract, SPE fractions and BG was evaluated in EO and compared to the AA of the synthetic antioxidants (BHT and TBHQ) and the natural antioxidant (GA) .…”

Effect of industrial processing for obtaining guava paste on the antioxidant compounds of guava (Psidium guajava l.) ‘Paluma’ cv.

“…Sousa et al (2011a) found that acerola and guava had the highest concentration of total phenolics when compared to other tropical fruits (such as pineapple, bacuri, cupuaçu and graviola). An interest in quantifying these compounds even in parts such as guava seeds (HERNÁNDEZ-ACOSTA et al, 2011), and guava leaves (SEO et al, 2014;ZAHIN et al, 2016) and other by-products (ARAÚJO et al, 2014) was also observed, aiming at their use as input in other industries. Zahin et al (2016) reported that guava is a promising fruit to be exploited, due to its high amount of phenolic compounds, which according to the authors, would be responsible for a large part of the antioxidant properties of guava.…”

Applications of Supercritical Fluids in Latin America: Past, Present and Future Trends

“…Extraction of phenolic fraction from guava seeds (Psidium guajava L.) using supercritical carbon dioxide and co-solvents 2010 [180] Extraction of pesticides from soil using supercritical carbon dioxide added with methanol as co-solvent 2012 [181] Design and analysis of antioxidant compounds from Andes Berry fruits (Rubus glaucus Benth) using an enhanced-fluidity liquid extraction process with CO 2 and ethanol 2012 [182] Extraction of oil from chia seeds with supercritical CO 2 2011 [183] Guava (Psidium guajava L.) seed oil obtained with a homemade supercritical fluid extraction system using supercritical CO 2 and co-solvent 2011 [184] Lippia origanoides chemotype differentiation based on essential oil GC-MS and principal component analysis 2011 [185] Integrated utilization of guava (Psidium guajava l.): antioxidant activity of phenolic extracts obtained from guava seeds with supercritical CO 2 -ethanol 2011 [186] Extraction of phenolic fraction from guava seeds (Psidium guajava L.) using supercritical carbon dioxide and co-solvents 2010 [180] Separation of fractions from vacuum residue by supercritical extraction 2010 [187] Reacting flow simulations of supercritical water oxidation of PCB-contaminated transformer oil in a pilot plant reactor 2011 [188] Reactions in supercritical fluids Biodiesel fuels through a continuous flow process of chicken fat supercritical transesterification 2010 [189] On the center of mass velocity in molecular dynamics simulations 2012 [190] [192] Solubility of mesquite gum in supercritical carbon dioxide 2011 [193] New apparatus for solubility measurements of solids in carbon dioxide 2011 [194] Loci of extrema of thermodynamic response functions for the Lennard-Jones fluid 2011 [195] Solubility and density measurements of palmitic acid in supercritical carbon dioxide plus alcohol mixtures 2010 [196] Material and micronization applications…”