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1.
Food Chem ; 324: 126874, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32353658

RESUMEN

Thermally-processed coconut water often develop a commercially-undesirable pink color, thus, NMR, UPLC-HRMS, GC-MS analyses combined with chemometrics approach were applied to evaluate chemical variations in comparison to tender water (control) that could explain such color change. Chemometrics on negative ionization mode dataset showed trimeric and A-type dimeric procyanidins, and caffeoylshikimic acid as main identified secondary metabolites induced by processing, while, control water presented mainly cytokinin trans-zeatin riboside, procyanidin dimer, caffeoylshikimic acid and trihydroxy-octadecenoic acid. Processing increased long-chain saturated palmitic and stearic fatty acids contents, meanwhile NMR analysis showed a decline in primary metabolites content as sugars fructose and glucose, and short-chain organic acids. Among the results observed for thermally processed coconut water, the increase in oligomeric procyanidins as A-type dimer and trimer may be associated with pink color development as these are precursors of anthocyanin pigment and/or by enhancing color stability of anthocyanin solutions.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cocos/química , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Antocianinas/análisis , Antocianinas/aislamiento & purificación , Cocos/metabolismo , Color , Citocininas/análisis , Citocininas/aislamiento & purificación , Fructosa/análisis , Fructosa/aislamiento & purificación , Análisis de Componente Principal , Proantocianidinas/análisis , Proantocianidinas/aislamiento & purificación , Extracción en Fase Sólida , Temperatura
2.
Artículo en Inglés | MEDLINE | ID: mdl-28285020

RESUMEN

Cashew immature and ripe peduncles (Anacardium occidentale L.) from orange- and red-colored clones CCP 76 and BRS 189, respectively, were prepared as juice or fibrous fraction and submitted to UPLC-MS analyses, while the soluble fraction was also submitted to enzymatic evaluation. Cinnamoyl glucoside was present in ripe juice samples from both cashew clones, while monogalloyl diglucoside and digalloyl glucoside were present in immature juice samples from both cashew clones. Four compounds were found at immature fiber of both clones, anacardic acids (1, 2, 3) and GA19. The phenolic biosynthetic pathway was evaluated in juice samples and phenylalanine ammonia-lyase activity decreased significantly during the development, although it was much higher in ripe CCP 76. UDP-glycosyltransferases activity differed between clones, however its product cinnamoyl glucoside was a possible chemical marker of ripe juice samples from both clones. Flavonol synthase showed the highest specific activity in both cashew clones and its product, flavonols were identified in cashew apple at immature and ripe stages.


Asunto(s)
Ácidos Anacárdicos/análisis , Anacardium/enzimología , Anacardium/crecimiento & desarrollo , Frutas/enzimología , Frutas/crecimiento & desarrollo , Glucósidos/análisis , Fenoles/análisis , Ácidos Anacárdicos/metabolismo , Anacardium/química , Anacardium/metabolismo , Vías Biosintéticas , Cromatografía Líquida de Alta Presión , Frutas/química , Frutas/metabolismo , Glucósidos/metabolismo , Glucuronosiltransferasa/metabolismo , Oxidorreductasas/metabolismo , Fenoles/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Proteínas de Plantas/metabolismo , Espectrometría de Masas en Tándem
3.
Appl Biochem Biotechnol ; 156(1-3): 133-45, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19037600

RESUMEN

Lipases are an enzyme class of a great importance as biocatalysts applied to organic chemistry. However, it is still necessary to search for new enzymes with special characteristics such as good stability towards high temperatures, organic solvents, and high stereoselectivity presence. The present work's aim was to immobilize the lipases pool produced by Penicillium simplissicimum, a filamentous fungi strain isolated from Brazilian babassu cake residue. P. simplissicimum lipases were separated into three different fractions using selective adsorption method on different hydrophobic supports (butyl-, phenyl-, and octyl-agarose) at low ionic strength. After immobilization, it was observed that these fractions' hyperactivation is in the range of 131% to 1133%. This phenomenon probably occurs due to enzyme open form stabilization when immobilized onto hydrophobic supports. Those fractions showed different thermal stability, specificity, and enantioselectivity towards some substrates. Enantiomeric ratio for the hydrolysis of (R,S) 2-O-butyryl-2-phenylacetic acid ranged from 1 to 7.9 for different immobilized P. simplissicimum lipase fractions. Asymmetry factor for diethyl 2-phenylmalonate hydrolysis ranged from 11.8 to 16.4 according to the immobilized P. simplissicimum lipase fractions. Those results showed that sequential adsorption methodology was an efficient strategy to obtain new biocatalysts with different enantioselectivity degrees, thermostability, and specificity prepared with a crude extract produced by a simple and low-cost technology.


Asunto(s)
Enzimas Inmovilizadas/metabolismo , Lipasa/aislamiento & purificación , Lipasa/metabolismo , Penicillium/metabolismo , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Estereoisomerismo
4.
Appl Biochem Biotechnol ; 146(1-3): 49-56, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18421586

RESUMEN

Lipase immobilization offers unique advantages in terms of better process control, enhanced stability, predictable decay rates and improved economics. This work evaluated the immobilization of a highly active Yarrowia lipolytica lipase (YLL) by physical adsorption and covalent attachment. The enzyme was adsorbed on octyl-agarose and octadecyl-sepabeads supports by hydrophobic adsorption at low ionic strength and on MANAE-agarose support by ionic adsorption. CNBr-agarose was used as support for the covalent attachment immobilization. Immobilization yields of 71, 90 and 97% were obtained when Y. lipolytica lipase was immobilized into octyl-agarose, octadecyl-sepabeads and MANAE-agarose, respectively. However, the activity retention was lower (34% for octyl-agarose, 50% for octadecyl-sepabeads and 61% for MANAE-agarose), indicating that the immobilized lipase lost activity during immobilization procedures. Furthermore, immobilization by covalent attachment led to complete enzyme inactivation. Thermal deactivation was studied at a temperature range from 25 to 45 degrees C and pH varying from 5.0 to 9.0 and revealed that the hydrophobic adsorption on octadecyl-sepabeads produced an appreciable stabilization of the biocatalyst. The octadecyl-sepabeads biocatalyst was almost tenfold more stable than free lipase, and its thermal deactivation profile was also modified. On the other hand, the Y. lipolytica lipase immobilized on octyl-agarose and MANAE-agarose supports presented low stability, even less than the free enzyme.


Asunto(s)
Lipasa/química , Yarrowia/enzimología , Adsorción , Sitios de Unión , Activación Enzimática , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Unión Proteica , Especificidad por Sustrato
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