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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.
J Agric Food Chem ; 68(20): 5596-5605, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32343573

RESUMEN

Vicilins are related to cowpea seed resistance toward Callosobruchus maculatus due to their ability to bind to chitinous structures lining larval midgut. However, this binding mechanism is not fully understood. Here, we identified chitin binding sites and investigated how in vitro and in silico chemical modifications interfere with vicilin chitin binding and insect toxicity. In vitro assays showed that unmodified vicilin strongly binds to chitin matrices, mainly with acetylated chitin. Chemical modifications of specific amino acids (tryptophan, lysine, tyrosine), as well as glutaraldehyde cross-linking, decreased the evaluated parameters. In silico analyses identified at least one chitin binding site in vicilin monomer, the region between Arg208 and Lys216, which bears the sequence REGIRELMK and forms an α helix, exposed in the 3D structure. In silico modifications of Lys223 (acetylated at its terminal nitrogen) and Trp316 (iodinated to 7-iodine-L-tryptophan or oxidized to ß-oxy-indolylalanine) decreased vicilin chitin binding affinity. Glucose, sucrose, and N-acetylglucosamine also interfered with vicilin chitin binding affinity.


Asunto(s)
Quitina/metabolismo , Escarabajos/metabolismo , Proteínas de Almacenamiento de Semillas/química , Proteínas de Almacenamiento de Semillas/farmacología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Quitina/química , Escarabajos/química , Escarabajos/efectos de los fármacos , Simulación por Computador , Larva/química , Larva/efectos de los fármacos , Larva/metabolismo , Unión Proteica , Proteínas de Almacenamiento de Semillas/genética , Proteínas de Almacenamiento de Semillas/metabolismo , Vigna/química , Vigna/genética , Vigna/metabolismo
3.
Food Chem ; 257: 252-258, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29622207

RESUMEN

The quality of zein (Z)- and zein-tannic acid (ZTA)-coated guavas was monitored throughout 12 days of storage. Coated fruit showed lower changes in terms of visual appearance, chlorophyll contents and color. Weight loss, softening, and changes in soluble solids were also decreased by the coatings. The respiration peak as well as H2O2 and superoxide dismutase activity peaks were delayed by the coatings, and the ethylene production was reduced. So, the results were consistent with a slowed down ripening of guavas by the coatings, which was probably related to lowered oxygen permeability of guava skin. ZTA coating was more effective than Z to reduce weight loss, softening, color changes, ethylene production, and oxidative stress. The higher efficiency of ZTA coating was ascribed to zein crosslinking, which probably resulted in decreased gas permeability, promoting lower respiration rates and lower ROS production, slowing down the ripening process, and extending guava stability.


Asunto(s)
Almacenamiento de Alimentos/métodos , Psidium/fisiología , Taninos/química , Zeína/química , Clorofila/metabolismo , Color , Reactivos de Enlaces Cruzados/química , Etilenos/metabolismo , Calidad de los Alimentos , Frutas/fisiología , Peróxido de Hidrógeno/metabolismo , Estrés Oxidativo , Superóxido Dismutasa/metabolismo , Temperatura
4.
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
5.
Exp Biol Med (Maywood) ; 240(12): 1648-55, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25819683

RESUMEN

Cashew apple is a tropical pseudofruit consumed as juice due to its excellent nutritional and sensory properties. In spite of being well known for its important antioxidant properties, the cashew apple has not been thoroughly investigated for its therapeutic potential. Thereby, this study evaluated the antioxidant capacity, anti-inflammatory, and wound-healing activities of cashew apple juice. Juices from ripe and immature cashew apples were analyzed for antioxidant, anti-inflammatory, and wound-healing properties. Those were evaluated in murine models of xylene-induced ear edema and wound excision. Swiss mice were treated with cashew juice by gavage. Edema thickness was measured and skin lesions were analyzed by planimetry and histology. Both antioxidant content and total antioxidant activity were higher in ripe cashew apple juice (RCAJ) than in unripe cashew apple juice (UNCAJ). The UNCAJ presented the main anti-inflammatory activity by a significant inhibition of ear edema (66.5%) when compared to RCAJ (10%). Moreover, UNCAJ also showed the best result for wound contraction (86.31%) compared to RCAJ (67.54%). Despite of higher antioxidant capacity, RCAJ did not promote better anti-inflammatory, and healing responses, which may be explained by the fact that treatment increased antioxidants level leading to a redox "imbalance" turning down the inflammatory response modulation exerted by reactive oxygen species (ROS). The results suggest that UNCAJ presents a greater therapeutic activity due to a synergistic effect of its phytochemical components, which improve the immunological mechanisms as well as an optimal balance between ROS and antioxidants leading to a better wound healing process.


Asunto(s)
Anacardium/química , Antiinflamatorios/uso terapéutico , Jugos de Frutas y Vegetales , Inflamación/tratamiento farmacológico , Fitoterapia/métodos , Cicatrización de Heridas/efectos de los fármacos , Animales , Frutas/química , Masculino , Ratones , Otitis/tratamiento farmacológico , Piel/efectos de los fármacos , Piel/patología
6.
PLoS One ; 8(2): e56354, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23437115

RESUMEN

This study was conducted with the objective of testing the hypothesis that tomato fruits from organic farming accumulate more nutritional compounds, such as phenolics and vitamin C as a consequence of the stressing conditions associated with farming system. Growth was reduced in fruits from organic farming while titratable acidity, the soluble solids content and the concentrations in vitamin C were respectively +29%, +57% and +55% higher at the stage of commercial maturity. At that time, the total phenolic content was +139% higher than in the fruits from conventional farming which seems consistent with the more than two times higher activity of phenylalanine ammonia lyase (PAL) we observed throughout fruit development in fruits from organic farming. Cell membrane lipid peroxidation (LPO) degree was 60% higher in organic tomatoes. SOD activity was also dramatically higher in the fruits from organic farming. Taken together, our observations suggest that tomato fruits from organic farming experienced stressing conditions that resulted in oxidative stress and the accumulation of higher concentrations of soluble solids as sugars and other compounds contributing to fruit nutritional quality such as vitamin C and phenolic compounds.


Asunto(s)
Frutas/crecimiento & desarrollo , Agricultura Orgánica , Estrés Oxidativo , Solanum lycopersicum/crecimiento & desarrollo , Clorofila/metabolismo , Frutas/metabolismo , Solanum lycopersicum/metabolismo , Modelos Biológicos , Fenoles/metabolismo
7.
Plant Physiol Biochem ; 45(10-11): 781-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17888673

RESUMEN

The laticifer fluid of Calotropis procera is rich in proteins and there is evidence that they are involved in the pharmacological properties of the latex. However, not much is known about how the latex-containing proteins are produced or their functions. In this study, laticifer proteins of C. procera were pooled and examined by 1D and 2D electrophoresis, masses spectrometry (MALDI-TOF) and characterized in respect of proteolytic activity and oxidative enzymes. Soluble laticifer proteins were predominantly composed of basic proteins (PI>6.0) with molecular masses varying between 5 and 95 kDa. Proteins with a molecular mass of approximately 26,000 Da were more evident. Strong anti-oxidative activity of superoxide dismutase (EC 1.15.1.1) (1007.74+/-91.89 Ug(-1)DM) and, to a lesser extent ascorbate peroxidase (EC 1.11.1.1) (0.117(d)+/-0.013 microMol H(2)O(2)g(-1)min(-1)), were detected. However, catalase (EC 1.11.1.6) was absent. The strong proteolytic activities of laticifer proteins from C. procera were shown to be shared by at least four distinct cysteine proteinases (EC 3.4.22.16) that were isolated by gel filtration chromatography. Serine and metaloproteinases were not detected and aspartic proteinase activities were barely visible. Chitinases (EC 3.2.1.14) were also isolated in a chitin column and their activities quantified. The presence of these enzymatic activities in latex from C. procera may confirm their involvement in resistance to phytopathogens and insects, mainly in its leaves where the latex circulates abundantly.


Asunto(s)
Calotropis/metabolismo , Látex/metabolismo , Proteínas de Plantas/metabolismo , Ascorbato Peroxidasas , Quitina/química , Quitina/metabolismo , Quitinasas/química , Quitinasas/metabolismo , Cromatografía de Afinidad , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/metabolismo , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Látex/química , Peso Molecular , Peroxidasas/química , Peroxidasas/metabolismo , Proteínas de Plantas/química , Protones , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Superóxido Dismutasa/química , Superóxido Dismutasa/metabolismo , Temperatura
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