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1.
Sci Rep ; 10(1): 21972, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319819

RESUMO

The effects of ultraviolet-C light (UVC) on vitamin C and phenolic compounds in acerola during postharvest storage were investigated in order to elucidate the mechanism inducing the antioxidant systems. The fruits, stored at 10 °C for 7 days after a hormetic UVC irradiation (two pulses of 0.3 J/cm2), showed significantly less degradation of vitamin C and phenolic compounds than the control without the UVC challenge. UVC activated the L-galactono-1,4-lactone dehydrogenase (GalDH), a key enzyme for vitamin C biosynthesis, and altered the composition of phenolic compounds, through phenolic biosynthesis, in acerola during postharvest storage. UVC also induced reactive oxygen species (ROS) productions at immediate (day 0) and late (day 7) times during postharvest storage through the mitochondrial electron transport chain and NADPH oxidase, respectively. Results suggest that UVC helps in the retention of vitamin C and phenolic content in acerola by altering ascorbic acid and phenolic metabolism through an increase in mitochondrial activity and a ROS-mediated mechanism. Data showed the beneficial effects of UVC on maintenance of nutraceutical quality in acerola during postharvest storage and supplied new insights into understanding the mechanism by which UVC irradiation enhance the antioxidant system in fruits.


Assuntos
Ácido Ascórbico/biossíntese , Malpighiaceae/metabolismo , Malpighiaceae/efeitos da radiação , Mitocôndrias/metabolismo , Fenóis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta , Ácido Ascórbico/metabolismo , Vias Biossintéticas , Catecol Oxidase/metabolismo , Flavonoides/análise , Regulação da Expressão Gênica/efeitos dos fármacos , Hidroxibenzoatos/análise , Mitocôndrias/efeitos da radiação , Modelos Biológicos , NADPH Oxidases/metabolismo , Oxirredutases/metabolismo , Fenilalanina Amônia-Liase/metabolismo
2.
Food Chem ; 324: 126874, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353658

RESUMO

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.


Assuntos
Cromatografia Líquida de Alta Pressão , Cocos/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Antocianinas/análise , Antocianinas/isolamento & purificação , Cocos/metabolismo , Cor , Citocininas/análise , Citocininas/isolamento & purificação , Frutose/análise , Frutose/isolamento & purificação , Análise de Componente Principal , Proantocianidinas/análise , Proantocianidinas/isolamento & purificação , Extração em Fase Sólida , Temperatura
3.
J Agric Food Chem ; 68(20): 5596-5605, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32343573

RESUMO

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.


Assuntos
Quitina/metabolismo , Besouros/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/farmacologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Quitina/química , Besouros/química , Besouros/efeitos dos fármacos , Simulação por Computador , Larva/química , Larva/efeitos dos fármacos , Larva/metabolismo , Ligação Proteica , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo , Vigna/química , Vigna/genética , Vigna/metabolismo
4.
Sci Rep ; 8(1): 15141, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310165

RESUMO

The Phyllanthus genus is widely distributed in tropical and subtropical areas of the world and present several pharmacological applications. Drought is a restrictive factor for crop development and production, and is becoming a severe problem in many regions of the world. The species Phyllanthus amarus and Phyllanthus niruri were subjected to drought stress for varying periods of time (0, 3, 5, 7, and 10 days), and afterwards, leaves were collected and evaluated for physiological and biochemical responses, such as oxidative stress markers and drought-associated defense mechanisms. Results show that P. amarus has an endogenously higher level of variables of the oxidative/antioxidant metabolism, and P. niruri presents the most significant changes in those variables when compared to control and stressed plants. For both Phyllanthus species, drought stress induces higher levels of organic acids such as malic, succinic, and citric acids, and amino acids such as proline, GABA, alanine, and valine. Moreover, P. niruri plants respond with greater glucose and corilagin contents. Therefore, considering the evaluated metabolic changes, P. amarus is better adapted to drought-stress, while P. niruri presents an acclimation strategy that increases the corilagin levels induced by short-term drought stress.


Assuntos
Adaptação Biológica , Secas , Phyllanthus/fisiologia , Estresse Fisiológico , Antioxidantes/metabolismo , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Estresse Oxidativo
5.
Foods ; 7(8)2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30061481

RESUMO

Plant extracts have the potential to be used as food additives; however, their use have been limited by causing undesirable changes in the sensory attributes of foods. We characterized the mango seed extract as a preserving agent for fresh-cut mangoes. We established the maximum concentration of extract that, while increasing the antioxidant activity, and limiting microbial contamination of the fruit, did not negatively affect fruit sensory acceptability. The extract contained 277.4 g gallic acid equivalent (GAE)/kg dw (dry weight) of polyphenols and 143.7 g quercetin equivalent (QE)/kg dw of flavonoids. Antioxidant capacity values were 2034.1 and 4205.7 µmol Trolox equivalent (TE)/g against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, respectively. Chromatographic analysis revealed the presence of gallic and chlorogenic acids. The extract (16 g/L) inhibited the growth of Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and Listeria monocytogenes. The highest concentration with sensory acceptability was 6.25 g/L. At such concentration, the extract preserved fresh-cut fruits, increasing polyphenols (0.427 g GAE/kg fw (fresh weight)), flavonoid content (0.234 g QE/kg fw) and antioxidant activity (DPPH = 2.814 and ABTS = 0.551 mol TE/kg fw). It also reduced inoculated bacteria (range: 5.50 × 10³ to 1.44 × 105 colony forming units (CFU)/g). These results showed the importance of considering consumer acceptability to determine the effective concentration of plant extracts as additives.

6.
Food Chem ; 257: 252-258, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622207

RESUMO

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.


Assuntos
Armazenamento de Alimentos/métodos , Psidium/fisiologia , Taninos/química , Zeína/química , Clorofila/metabolismo , Cor , Reagentes de Ligações Cruzadas/química , Etilenos/metabolismo , Qualidade dos Alimentos , Frutas/fisiologia , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Temperatura
7.
J Food Sci Technol ; 54(8): 2332-2340, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28740290

RESUMO

This study investigated the effect of pulsed light (PL) on the respiratory rate, quality (firmness, color and soluble solid content), bioactive compounds (ascorbate and carotenoid) and total antioxidant activity of fresh-cut "Tommy Atkins" mangoes. Fresh-cut mangoes were subjected to PL treatments: control (0P), 1 pulse (1P; 0.7 J cm-2), 4 successive pulses (4P; 2.80 J cm-2) and 1 pulse per day for 4 days (1P4D; 2.80 J cm-2) before storage for 7 days at 6 °C. The 1P and the 4P treatments reduced fresh mass loss during storage, while 4P-treated samples also showed a slower decline of yellow color, as shown by parameter b and overall better visual appearance. After 7 days of storage, total ascorbate content was 40% higher in the 1P4D treatment than in control, whereas total carotenoid content (0.894 mg g-1 FM) and total antioxidant activity (144 µmol trolox 100 g-1 FM) were the highest in the 4P-treated samples. Results suggest that PL mode of application is more important than the fluence or final dose received by fresh-cut mangoes; moreover, 4P is an effective method to preserve, or even improve quality of fresh-cut mangoes.

8.
Artigo em Inglês | MEDLINE | ID: mdl-28285020

RESUMO

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.


Assuntos
Ácidos Anacárdicos/análise , Anacardium/enzimologia , Anacardium/crescimento & desenvolvimento , Frutas/enzimologia , Frutas/crescimento & desenvolvimento , Glucosídeos/análise , Fenóis/análise , Ácidos Anacárdicos/metabolismo , Anacardium/química , Anacardium/metabolismo , Vias Biossintéticas , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Glucosídeos/metabolismo , Glucuronosiltransferase/metabolismo , Oxirredutases/metabolismo , Fenóis/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem
9.
Plant Physiol Biochem ; 105: 1-11, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27064192

RESUMO

There is an abundant literature about the biological and physiological effects of UV-B light and the signaling and metabolic pathways it triggers and influences. Much less is known about UV-C light even though it seems to have a lot of potential for being effective in less time than UV-B light. UV-C light is known since long to exert direct and indirect inhibitory and damaging effects on living cells and is therefore commonly used for disinfection purposes. More recent observations suggest that UV-C light can also be exploited to stimulate the production of health-promoting phytochemicals, to extent shelf life of fruits and vegetables and to stimulate mechanisms of adaptation to biotic and abiotic stresses. Clearly some of these effects may be related to the stimulating effect of UV-C light on the production of reactive oxygen species (ROS) and to the stimulation of antioxidant molecules and mechanisms, although UV-C light could also trigger and regulate signaling pathways independently from its effect on the production of ROS. Our review clearly underlines the high potential of UV-C light in agriculture and therefore advocates for more work to be done to improve its efficiency and also to increase our understanding of the way UV-C light is perceived and influences the physiology of plants.


Assuntos
Agricultura , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/efeitos da radiação , Fenômenos Fisiológicos Vegetais/efeitos da radiação , Raios Ultravioleta , Adaptação Fisiológica/efeitos da radiação , Células Vegetais/efeitos da radiação
10.
Ciênc. rural ; 45(11): 1946-1952, Nov. 2015. graf
Artigo em Português | LILACS | ID: lil-762946

RESUMO

Objetivou-se avaliar o efeito dos danos mecânicos provocados por impacto, corte e abrasão sobre a qualidade de banana 'Prata Catarina', submetida ao armazenamento refrigerado (14°C ±1ºC e 84% ±5% de UR durante 21 dias). Os frutos foram provenientes de um pomar comercial, localizado no município de Limoeiro do Norte-CE. O experimento foi instalado em delineamento inteiramente ao acaso, no esquema de parcelas subdivididas no tempo, tendo-se, nas parcelas, as amostragens ao longo do tempo e, nas subparcelas, os quatro tratamentos: testemunha ou ausência de dano mecânico (T1), impacto (T2), abrasão (T3) e corte (T4), com quatro repetições de dois frutos cada. Os danos por impacto e abrasão foram os que proporcionaram maior velocidade de amadurecimento, sendo que o dano por impacto proporcionou maior atividade da enzima polifenoloxidase. As bananas 'Prata Catarina' que não sofreram danos podem ser comercializadas por até 21 dias de armazenamento (14°C ± 1ºC e 84% ±5% UR), sem perda da qualidade.


The aim of this study was to evaluate the effect of mechanical damages caused by impact, cut and abrasion on the quality of 'Prata Catarina' banana subjected to cold storage (14°C±1°C and 84%±5% RH for 21 days). The fruits were from a commercial orchard in the city of Limoeiro do Norte-CE. The experiment was conducted in a completely randomized design in split plot in time, taking up the samples in portions over time and in the subplots the four treatments: control or absence of mechanical damage (T1), impact (T2), abrasion (T3) and cut (T4), with 4 replicates of 2 fruits. Damages by impact and abrasion were the ones which provided the highest speed of ripening, and the damage caused by impact provided greater polyphenoloxidase enzyme activity. 'Prata Catarina' bananas that suffered no damage can be marketed until 21 days of storage (14°C±1°C and RH 84%±5%), without loss of quality.

11.
Exp Biol Med (Maywood) ; 240(12): 1648-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25819683

RESUMO

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.


Assuntos
Anacardium/química , Anti-Inflamatórios/uso terapêutico , Sucos de Frutas e Vegetais , Inflamação/tratamento farmacológico , Fitoterapia/métodos , Cicatrização/efeitos dos fármacos , Animais , Frutas/química , Masculino , Camundongos , Otite/tratamento farmacológico , Pele/efeitos dos fármacos , Pele/patologia
12.
J Food Sci Technol ; 51(11): 3293-300, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396323

RESUMO

The effects of a clarifying process using pectinases and chitosan on the physicochemical characteristics, antioxidant capacity and quality attributes of açaí fruit (Euterpe oleracea Mart.) juice were evaluated. Clarification of acaí pulp resulted (P ≤ 0.05) in a 50 % loss of total anthocyanin (4.2730 mg/100 mL) and 29 % reduction in antioxidant capacity (33.60 µM FeSO4/g). A high association (P ≤ 0.05) was found between the decrease of antioxidant capacity and total anthocyanin loss. The use of pectinases associated with chitosan as an aid for clarification of açaí juice proved to be highly effective and resulted in a clear juice with a brighter purple to red color that was free of lipids, insoluble solids, and others substances that cause hazes. The obtained clarified açaí juice is a genuinely high-value anthocyanin-rich product that could be used as colorant and functional ingredient to fruit juices and soft drinks.

13.
PLoS One ; 8(2): e56354, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23437115

RESUMO

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.


Assuntos
Frutas/crescimento & desenvolvimento , Agricultura Orgânica , Estresse Oxidativo , Solanum lycopersicum/crescimento & desenvolvimento , Clorofila/metabolismo , Frutas/metabolismo , Solanum lycopersicum/metabolismo , Modelos Biológicos , Fenóis/metabolismo
14.
J Agric Food Chem ; 60(32): 7957-64, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22834960

RESUMO

The present research work describes the major changes in the antioxidant properties during development of acerola from five different clones. Ripening improved fruit physicochemical quality parameters; however, total vitamin C and total soluble phenols (TSP) contents declined during development, which resulted in a lower total antioxidant activity (TAA). Despite the decline in TSP, at ripening, the anthocyanin and yellow flavonoid content increased and was mainly constituted of cyanidin 3-rhamnoside and quercetin 3-rhamnoside, respectively. The activities of oxygen-scavenging enzymes also decreased with ripening; furthermore, the reduction in vitamin C was inversely correlated to membrane lipid peroxidation, indicating that acerola ripening is characterized by a progressive oxidative stress. Among the studied clones, II47/1, BRS 237, and BRS 236 presented outstanding results for vitamin C, phenols, and antioxidant enzyme activity. If antioxidants were to be used in the food supplement industry, immature green would be the most suitable harvest stage; for the consumer's market, fruit should be eaten ripe.


Assuntos
Antioxidantes/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Malpighiaceae , Antioxidantes/análise , Ácido Ascórbico/análise , Flavonoides/análise , Frutas/química , Peroxidação de Lipídeos , Estresse Oxidativo , Fenóis/análise
15.
J Agric Food Chem ; 57(17): 8056-61, 2009 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-19658384

RESUMO

Studies have shown that vicilins (7S storage proteins) from seeds were able to bind to the surface of the Callosobruchus maculatus larval midgut and to the peritrophic matrices of the midguts of Diatraea saccharalis and Tenebrio molitor , inhibiting larval development. Vicilins were also shown to inhibit yeast growth and bind to yeast cells through the association with chitin-containing structures. The present work studies the association of peptides from vicilins of genotypes of Vigna unguiculata (susceptible and resistant to bruchid) with acetylated chitin and the toxicity of vicilin fragments and chitin-binding vicilin fragments to C. maculatus and phytopathogenic fungi. Hydrolysis of vicilins with alpha-chymotrypsin results in a complex mixture of fragments that were separated by chitin-affinity chromatography. Chitin-binding peptides from both genotypes were toxic to C. maculatus larvae, and alpha-chymotrypsin-hydrolyzed vicilins were deleterious to the above insect and to Fusarium oxysporum , Colletotrichum musae , and Saccharomyces cerevisiae fungi.


Assuntos
Besouros , Fungicidas Industriais/farmacologia , Inseticidas , Proteínas de Armazenamento de Sementes/farmacologia , Sementes/química , Animais , Quitina/metabolismo , Quimotripsina/metabolismo , Colletotrichum/efeitos dos fármacos , Fabaceae/química , Fusarium/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas de Armazenamento de Sementes/metabolismo
16.
Plant Physiol Biochem ; 45(10-11): 781-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17888673

RESUMO

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.


Assuntos
Calotropis/metabolismo , Látex/metabolismo , Proteínas de Plantas/metabolismo , Ascorbato Peroxidases , Quitina/química , Quitina/metabolismo , Quitinases/química , Quitinases/metabolismo , Cromatografia de Afinidade , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Látex/química , Peso Molecular , Peroxidases/química , Peroxidases/metabolismo , Proteínas de Plantas/química , Prótons , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Temperatura
17.
Acta méd. costarric ; 47(1): 51-52, ene.-mar. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-401237

RESUMO

Se reporta el caso de una paciente de 36 años, con perforación uterina y del colon sigmoides con una Tcu colocada 14 años atrás, y que evolucionó en forma asintomática. El manejo requirió de histerectomía abdominal, con reparación de colon sigmoides y colostomía transversa temporal con evolución final satisfactoria. La perforación uterina por dispositivos intrauterinos (DIU), constituye una complicación poco frecuente, y puede acompañarse de perforación de otras víceras en el 15 por ciento, de los casos principalmente del intestino. Descriptores: DIU, perforación uterina, complicaciones


Assuntos
Humanos , Adulto , Feminino , Colo , Dispositivos Intrauterinos de Cobre , Perfuração Uterina/etiologia , Perfuração Uterina/terapia , Costa Rica
18.
Acta méd. costarric ; 46(4): 201-203, oct.-dic. 2004. ilus
Artigo em Espanhol | LILACS | ID: lil-403776

RESUMO

Se reporta el caso de una paciente de 63 años, con 6 años de evolución de alopecia, hirsutismo, voz ronca y clitorimegalia. Se le encontraron niveles altos de testosterona (263 ng/dl), el ultrasonido transvaginal demostró una lesión sólida en el ovario izquierdo. El manejo consistió en histerectomía abdominal y salpingooforectomía bilateral. La biopsia indicó un tumor benigno esteroidogénico tipo células de Leydig. La paciente evolucionó satisfactoriamente, con mejoría parcial de sus manifestaciones en el control postoperatorio de 4 meses. Descriptores: Hirsutismo, alopecia, clitorimegalia, tumor de células de Leydig.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Alopecia , Clitóris , Células Intersticiais do Testículo/patologia , Hirsutismo , Ovário , Costa Rica
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