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1.
Curr Issues Mol Biol ; 46(2): 1164-1176, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38392192

RESUMO

Activin A belongs to the transforming growth factor (TGF) family member, which exhibits a wide range of biological activities, including the regulation of cellular proliferation and differentiation and the promotion of neuronal survival. The isolation of AA from natural sources can only produce limited quantities of this bioactive protein. In this study, the whole gene of the precursor form of recombinant human activin A (rhAA) contains a signal peptide, and a pro-region and a mature region were cloned into an expression vector under the control of the rice α-amylase 3D (RAmy3D) promoter. To obtain the mature (active) form of rhAA, an enterokinase cleavage site was inserted between the pro-region and mature region of rhAA. The rice seed (Oryza sativa L. cv. Dongjin) was transformed with recombinant vectors by the Agrobacterium-mediated method, and the integration of the target gene into the plant genome was confirmed by genomic PCR. The transcript expression of rhAA in transgenic rice calli was confirmed by a Northern blot analysis of mRNA. The production of rhAA was verified by Western blot analysis and ELISA. The accumulation of secreted rhAA in the culture medium was purified by Ni2+-NTA. The mature form of AA was released from the precursor form of rhAA after proteolytically processing with enterokinase. Western blot shows that the mature AA was split into monomer and homodimer with molecular weights of 14 kDa and 28 kDa under reducing and non-reducing conditions, respectively. These results suggest that the mature form of rhAA could be produced and purified using transgenic rice cell suspension culture.

2.
Support Care Cancer ; 32(1): 88, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185720

RESUMO

PURPOSE: Research suggests that cancer-related cognitive impairment (CRCI) can occur before breast cancer (BC) treatment. The limited extant evidence suggests the underlying mechanisms could be stress-related. Potential psychological and biological predictors of CRCI prior to any BC treatment were examined. METHODS: 112 treatment-naïve women with BC and 67 healthy controls (HC) completed a neuropsychological test battery to assess cognitive impairment and a self-report battery to assess cognitive complaints, cancer-related stress, depressive and anxiety symptoms. Morning and evening cortisol and α-amylase were collected from saliva. Multilinear regressions were conducted. RESULTS: Treatment-naïve BC patients were more frequently impaired in verbal memory and processing speed and reported more cognitive complaints (all p < .001) than HC. BC patients and HC did not differ in overall cognitive impairment (p = .21). Steeper α-amylase, lower cancer-related stress and younger age was associated with better overall cognitive function in treatment-naïve BC patients. Higher depressive symptoms predicted higher levels of cognitive complaints in BC patients. CONCLUSION: Overall, these findings suggest that stress plays a role in CRCI. This study is the first to associate α-amylase with cognitive function in cancer patients, informing future research. The findings on impairment in processing speed and verbal memory among treatment-naïve BC highlight the need to screen for such impairments among BC patients and indicate that future studies on CRCI should include baseline assessments prior to BC treatment. If replicated, these findings could inform the development and testing of appropriate interventions to decrease CRCI among cancer patients. CLINICAL TRIALS REGISTRATION NUMBER: NCT04418856, date of registration: 06.05.2020.


Assuntos
Neoplasias da Mama , Disfunção Cognitiva , Humanos , Feminino , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Cognição , Disfunção Cognitiva/etiologia , Hidrocortisona , alfa-Amilases
3.
Int J Mol Sci ; 23(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36362160

RESUMO

Six α-amylase/subtilisin inhibitor genes (MnASIs) were identified from mulberry (Morus notabilis). In this study, bioinformatics and expression pattern analysis of six MnASIs were performed to determine their roles in resistance to B. cinerea. The expression of all six MnASIs was significantly increased under Botrytis cinerea infection. MnASI1, which responded strongly to B. cinerea, was overexpressed in Arabidopsis and mulberry. The resistance of Arabidopsis and mulberry overexpressing MnASI1 gene to B. cinerea was significantly improved, the catalase (CAT) activity was increased, and the malondialdehyde (MDA) content was decreased after inoculation with B. cinerea. At the same time, H2O2 and O2- levels were reduced in MnASI1 transgenic Arabidopsis, reducing the damage of ROS accumulation to plants. In addition, MnASI1 transgenic Arabidopsis increased the expression of the salicylic acid (SA) pathway-related gene AtPR1. This study provides an important reference for further revealing the function of α-amylase/subtilisin inhibitors.


Assuntos
Arabidopsis , Morus , Arabidopsis/genética , Arabidopsis/metabolismo , Morus/genética , Morus/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Doenças das Plantas/genética , Botrytis/metabolismo , Subtilisinas/metabolismo , alfa-Amilases/genética , alfa-Amilases/metabolismo , Resistência à Doença/genética
4.
Medicines (Basel) ; 7(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121132

RESUMO

Background: Clausena indica fruit is commonly used for food ingredients and traditional medicines in tropical countries, however, information about its biological activities and chemical profiles has been inadequately reported. Methods: In this study, a bio-guided fractionation of antioxidants and α-amylase inhibitors from hexane (MH) and ethyl acetate (ME) extracts of C. indica fruit (pericarp and seed) was carried out. Eleven fractions from MH (D1-D11) and 17 fractions from ME (T1-T17) were obtained from column chromatography over silica gel, which were then examined for anti-radical capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, and pancreatic α-amylase inhibition, a key enzyme linked to type 2 diabetes. Results: Of isolated fractions, the fraction T4 revealed the most potent anti-DPPH activity (IC50 = 0.13 mg/mL), whereas T2 exhibits the strongest ABTS cation scavenging ability (IC50 = 0.31 mg/mL). In the enzymatic assay, the fractions D3 and T4 significantly inhibit the α-amylase reaction with IC50 values of 0.34 and 0.86 mg/mL, respectively. Remarkably, α-amylase suppression of T4 is close to acarbose and over four times stronger than palmitic acid, which are the well-known α-amylase inhibitors (IC50 = 0.07 and 1.52 mg/mL, respectively). The active constituents from fractions were identified by gas chromatography-mass spectrometry (GC-MS). The results show that the fraction D3 contains five major compounds, which are grouped in five classes consisting of fatty acids, phenols, benzodioxoles, alcohols, and sesquiterpenes. Among them, palmitic acid is the most dominant compound (32.64%), followed by 2R-acetoxymethyl-1,3,3-trimethyl-4t-(3-methyl-2-buten-1-yl)-1t-cyclohexanol (16.69%). Whilst, six major compounds belonging to fatty acid and coumarin classes are identified in the fraction T4. The most abundant compound in T4 is dentatin (47.32%), followed by palmitic acid (15.11%). Conclusions: This is the first finding that C. indica fruit can be a promising source for the development of natural antioxidant and antidiabetic agents. Additionally, the outcome reveals that dentatin, a known natural antineoplastic agent, can be feasibly exploited from C. indica fruit.

5.
Bioorg Med Chem ; 27(7): 1414-1420, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30808605

RESUMO

A cationic derivative of γ-cyclodextrin (GCD) modified with propylenediamine (PDA) was synthesized. It was shown that the derivative (GCD-PDA) is mucoadhesive and resistant to the digestion with ∝-amylase indicating that it may constitute an efficient oral delivery vehicle. GCD-PDA formed an inclusion complex with berberine (BBR), an alkaloid displaying a multitude of beneficial physiological effects. The complexed BBR penetrates a lipid membrane easier than the free one. Both uncomplexed BBR and that complexed with GCD-PDA was delivered to normal (NMuMG) and cancerous (4T1) murine mammary gland cells. In the normal cells both free and complexed BBR was homogeneously dispersed in the cytoplasm and was nontoxic up to 131 µM. In the cancerous cells uncomplexed BBR was also homogeneously dispersed but it was toxic to about 25% of cells at 131 µM, while the GCD-PDA/BBR complex was preferably localized in lysosomes and its toxicity doubled at this concentration compared to that of free BBR. Moreover, free BBR and GCD-PDA/BBR showed even more efficient inhibitory effect against murine melanoma (B16-F10) cells than against 4T1 cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , gama-Ciclodextrinas/química , gama-Ciclodextrinas/farmacologia , Animais , Antineoplásicos/síntese química , Cátions/síntese química , Cátions/química , Cátions/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , gama-Ciclodextrinas/síntese química
6.
Rev. Soc. Odontol. La Plata ; 28(55): 41-45, mayo 2018.
Artigo em Espanhol | LILACS | ID: biblio-912038

RESUMO

Los inhibidores selectivos de la α-amilasa salival y pancreática humana, son un medio eficaz para controlar los niveles de azúcar en la saliva y la sangre, durante el control de la caries y la diabetes. En la presente revisión, después de identificar las principales funciones de la enzima, se discutieron exponen algunas de las respuestas observadas después de la exposición de la α-amilasa a las plantas, en escala molecular y entera. Diferentes tipos de moléculas de plantas medicinales actúan como inhibidores de la α-amilasa, como una terapia alternativa o complementaria en el tratamiento de la diabetes en y en el control de uno de los factores de la formación la caries (dieta) (AU)


Selective inhibitors of human salivary and pancreatic α-amylase are an effective means of controlling saliva and blood sugar levels in the management of caries and diabetes. In the present review, after identifying the main functions of the enzyme, it was exposed some of the observed responses after exposure to α-amylase at the molecular and whole plants scale. Different types of medicinal plants molecules have been found to act as α-amylase inhibitors, as an alternative or complementary therapy in the management of diabetes and control to one of the predisposing factors to caries (diet) (AU)


Assuntos
Humanos , alfa-Amilases , Cárie Dentária , Diabetes Mellitus , Inibidores Enzimáticos , Plantas Medicinais , Terapias Complementares , Inibidores de Glicosídeo Hidrolases
7.
J Contemp Dent Pract ; 19(3): 253-256, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29603693

RESUMO

INTRODUCTION: One of the common practices observed in many parts of the world is smoking, of which tobacco forms an important constituent which is burned and inhaled. Smoking is known to have potential effect on body's immune system, antioxidants level, and salivary cotinine levels. Hence, we planned the present study to evaluate the impact of cigarette smoke on salivary anti-oxidant levels and cotinine levels in smokers and nonsmokers. MATERIALS AND METHODS: The present study included assessment of salivary parameters of smokers and nonsmokers. A total of 400 subjects were analyzed, of which 200 were active smokers and 200 were nonsmokers. Unstimulated salivary samples were taken and assessment of a-amylase levels was done using biochemical kit and spectrophotometer. Assessment of salivary catalase (CAT) activity was done using Luck method. For the determination of cotinine levels, Bioassay Technology Laboratory kit was used using enzyme-linked immunosorbent assay (ELISA) technique. After the assessment of levels of all the salivary parameters, all the data were recorded, compiled, and analyzed. RESULTS: a-Amylase in smokers and nonsmokers group was found to be 206.25 and 169.85 U/mL respectively. Nonsignificant results were obtained while comparing the salivary a-amylase levels among the two study groups. Nonsignificant results were obtained while comparing the salivary CAT levels among the smokers and nonsmokers group. We observed statistically significant results while comparing mean cotinine levels among smokers group and nonsmokers group. CONCLUSION: Alteration in cotinine levels occurs in smokers in comparison to nonsmokers. CLINICAL SIGNIFICANCE: Smoking can cause harmful effect on the oral mucous membrane by altering salivary defense components.


Assuntos
Catalase/análise , Cotinina/análise , Saliva/química , Fumar/efeitos adversos , alfa-Amilases/análise , Adulto , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/enzimologia , Fumar/metabolismo , Espectrofotometria
8.
Iran J Pharm Res ; 15(Suppl): 37-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28228802

RESUMO

The side effects associated with the usage of synthetic antidiabetic drugs make it imperative to search for alternative drugs from medicinal plants. Therefore, this study was aimed at evaluating the α-amylase and α-glucosidase inhibitory potential of Calotropis procera leaf, as well as its possible mode of inhibiting these enzymes. Acetone, aqueous and ethanolic extracts of C. procera leaf was subjected to standard enzymes' inhibitory assay in-vitro using porcine pancreatic α-amylase and rat intestinal α-glucosidase. Results obtained showed that out of all the extracts tested, ethanolic and aqueous extracts possessed the best inhibition of α-amylase (IC50 7.80 mg/mL) and α-glucosidase (3.25 mg/mL) respectively. The kinetic analysis of the mode of inhibition of these enzymes by the leaf extracts of C. procera, revealed that these extracts inhibited both enzymes in a non-competitive manner. It is speculated that the α-amylase and α-glucosidase inhibitory properties of leaf extracts of C. procera may be due to the presence of some phytochemicals such as flavonoids, tannins and saponins in the plant. It can be concluded from this study that the Calotropis procera extracts could serve as source of antidiabetic agents which may act through the inhibition of carbohydrate hydrolyzing enzymes, α-amylase and α-glucosidase.

9.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-628465

RESUMO

Introduction: Medicinal plants have been reported to play an important role in modulating glycemic responses; they are also known to have preventive and therapeutic implications in disorders of carbohydrate and lipid metabolism. This study reports the possible hypoglycemic effects of Morus indica (Mulberry) and Costus speciosus (Insulin plant) in an in vitro system. Methods: Glucose adsorption, diffusion and starch hydrolysis of Mulberry leaf powder (MLP) and Insulin plant powder (IPP) were studied using in vitro techniques that simulated gastrointestinal conditions and compared with commercial dietary fibre sources such as wheat bran (WB), acarbose (ACB) and guar gum (GG) at three different levels (2, 4, and 6 %). Results: The glucose binding capacity of both Morus indica.L (MLP) and Costus speciosus (IPP)increased with increased levels and was significantly high compared to wheat bran and acarbose. At higher levels (4 and 6 %), the diffusion rate of glucose was lower compared to wheat bran, acarbose and guar gum. The a-amylase inhibitory effect was significantly high in MLP (51%) and IPP (18%) compared to WB (8%). The effect of samples on glucose diffusion was also studied in a system comprising of starch-a-amylase sample. The glucose diffusion rate was significantly low in the systems where MLP (6%) and IPP (6%) were used compared to the positive control and to commercial sources of fibre (ACB and GG). Conclusion: The data reveals that the samples may lower the rate of glucose absorption and as a result, decrease postprandial hyperglycemia by these mechanisms.

10.
Braz. arch. biol. technol ; 53(2): 301-309, Mar.-Apr. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-546560

RESUMO

Production of á- amylase under solid state fermentation by Streptomyces erumpens MTCC 7317 was investigated using cassava fibrous residue, one of the major solid waste released during extraction of starch from cassava (Manihot esculenta Crantz). Response surface methodology (RSM) was used to evaluate the effect of the main variables, i.e., incubation period (60 h), moisture holding capacity (60 percent) and temperature (50(0)C) on enzyme production by applying a full factorial Central Composite Design. Varying the inoculum concentration (5-25 percent) of S. erumpens showed that 15 percent inoculum (v/w, 2.5 x 10(6) CFU/ml) was the optimum for á- amylase production. Among the different nitrogen sources supplemented, beef extract was most suitable for enzyme production. The application of S. erumpens enzyme in liquefaction of soluble starch and cassava starch was studied. The maximum hydrolysis of soluble starch (85 percent) and cassava starch (70 percent) was obtained with the application of 5 ml crude enzyme (17185 units) after 5 h of incubation.

11.
Rev. colomb. quím. (Bogotá) ; 38(3): 395-408, sep.-dic. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-636668

RESUMO

Almidón de yuca comercial (variedad MTAI8) se sometió a modificación física por sinéresis, extrusión, gelatinización y secado por rodillos. Al almidón nativo y a los almidones modificados se les determinó su morfología, cristalinidad, distribución molecular y susceptibilidad a la hidrólisis enzimática con una alfa amilasa porcina pancreática. En los almidones modificados físicamente se incrementó el grado de hidrólisis, en comparación con el almidón nativo. Sin embargo no se observaron diferencias estadísticamente significativas en el grado de hidrólisis entre los almidones modificados. El patrón de difracción de rayos X tipo A, presentado por el almidón de yuca nativo y su propiedad birrefringente se alteraron por los pretratamientos, presentándose difractogramas de estructuras amorfas y pérdida de la cruz de malta en los almidones modificados. La microscopía electrónica de barrido (MEB) demostró alteración en la apariencia y estructura del gránulo nativo, dando lugar a partículas de formas irregulares con superficies fragmentadas y rugosas como resultado del proceso de modificación. La cromatografía de exclusión sobre sepharosa 6B confirmó la desaparición de la fracción de alto peso molecular presente en el almidón nativo, con el consecuente incremento de las fracciones de bajo peso molecular en los almidones modificados.


Cassava starch (MTAI 8 variety) was subjected to syneresis, gelatinization, extrusion and processing by drum dryers. The morphology, crystallinity, molecular weight distribution and susceptibility to enzyme hydrolysis by porcine pancreatic a-amylase were determined before and after the physical treatments. The physically modified starches increased the extent of a-amylolysis, compared to the native one. However, there were not significant differences in the degree of amylolisis between the treatments during the procedure. Both the X-ray pattern type-A, presentedinthecassavastarch, and its birrefringent property, observed in polarized light, were altered by the treatments causing amorphous structures and the loss of the Maltese cross. When the modified starches were observed n scann ng electron micrographs (SEM), an alteration in the appearance and structure of the native granule was shown, where particles with irregular shape and fragmented and wrinkled surfaces could be seen as a result of the modification process. The profile of the size exclusion chromatography on sepharose 6B showed two characteristic fractions of high and low molecular weight in the native starch, while in modified starches only one peak was obtained showing low molecular weight. The data showed that the treatments modified the physical structure of the starch granule, allowing more accessibility for the enzyme to the amorphous and crystalline regions of starch.


Amido de mandioca comercial (variedade MTAI 8) foi submetido a modificação física por sinérese, extrusão, gelatinização e secado por tambor. Foram determinados para o amido nativo e os amidos modificados a sua morfologia, cristalinidade, distribuição molecular y susceptibilidade à hidrólise enzimática com uma alfa amilase porcina pancreática. Nos amidos modificados fisicamente foi verificado um aumento do nível de hidrólise, em comparação com o amido nativo. Porém, não se observaram diferenças estatisticamente significativas no nível de hidrólise entre os almidões modificados. O padrão de difracção de raios-X tipo A apresentado pelo amido de mandioca nativo e a sua propriedade birrefringente, foram alterados pelos prétratamentos, apresentando-se difractogramas de estruturas amorfas y perda da cruz de malta nos almidões modificados. A microscopia electrónica de barrido (MEB) demonstrou alteração na aparência e estrutura do granulo nativo, dando lugar a partículas de formas irregulares com superfícies fragmentadas e rugosas como resultado do processo de modificação. A cromatografia de exclusão sobre sepharosa 6B corroborou a desaparição da fracção de alto peso molecular presente no amido nativo, com o consequente aumento das fracções de baixo peso molecular nos almidões modificados.

12.
Rev. colomb. quím. (Bogotá) ; 38(2): 191-208, ago. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-636655

RESUMO

Este estudio reporta la purificación y caracterización parcial de una a-amilasa producida por Penicillium commune mediante fermentación en fase sólida, empleando yuca blanca colombiana (Manihot esculenta Crantz) como soporte. La enzima fue purificada por precipitación fraccionada con sulfato de amonio, cromatografía de intercambio aniónico (DEAE-Sephadex A-50), cromatografía de filtración por gel (Sephadex G-75) y cromatografía de intercambio catiónico (CM-Sephadex C-50) obteniendo una actividad específica final de 314,82 U/mg, un grado de purificación del orden de 62 y un rendimiento de 9%. La purificación hasta la homogeneidad fue confirmada por SDS-PAGE. El peso molecular estimado fue 35 kDa. La enzima mostró máxima actividad de hidrólisis de almidón soluble con pH 6,0, y estabilidad en un intervalo de pH de 5,0-7,0. La estabilidad térmica de la enzima se presentó en el intervalo de temperatura 0-50 °C y su temperatura óptima fue 70 °C. Los iones Ca2+,Ba2+ y Ag+ aumentaron significativamente la actividad de la enzima, siendo el ión Ca2+ el que tuvo el más alto poder activador. Cu2+ no alteró significativamente la actividad de la enzima, mientras que Li+ yFe3+ la disminuyeron ligeramente (13%), y Co2+ y Hg2+ la disminuyeron 25% y 40% respectivamente. Los valores de Km y Vmáx fueron calculados usando la linealización de Lineweaver-Burk, con el resultado Km = 0,48 mg/mL y Vmáx = 5,85 µmol glucosa/min. Entre los principales productos de hidrólisis del almidón de yuca se encuentran la maltosa y la glucosa, este resultado proporciona evidencia de que la enzima es capaz de romper los enlaces glicosídicos a-1,4 del almidón, comportamiento característico de una a-amilasa.


This study reports the purification and partial characterization of an a-amylase from Penicillium commune produced by solid state fermentation using colombian white tapioca (Manihot esculenta Crantz) as support. The enzyme was purified by ammonium sulphate precipitation, anion exchange chromatography (DEAE-Sep-hadex A-50), gel filtration chromatography (Sephadex G-75) and cation exchange chromatography (CM-Sephadex C-50). A purification factor of 62 with a 9% yield and final specific activity of 314.82 U/mg were recorded. Purification to homogeneity was confirmed by SDS PAGE. The molecular weight was estimated to be 35 kDa. The enzyme shows maximal activity in the soluble starch hydrolysis at pH 6.0, and is stable in a range of pH from 5.0 to 7.0. Thermal stability was in the range of temperature from 0 to 50 °C, and its optimal temperature was 70 °C. Ions Ca2+,Ba2+ and Ag+ significantly increase the activity of the enzyme, with ion Ca2+ as the highest activator. Cu2+ does not alter significantly the activity of the enzyme, whereas Li+ and Fe3+ decrease it slightly (13%) and Co2+ and Hg2+ decrease it 25% and 40% respectively. Km = 0.48 mg/mL and Vmax = 5.85 /xmol glucose/min were calculated using the linearization of Lineweaver-Burk. Among hydrolysis products of tapioca starch are maltose and glucose, this result provides evidence of the enzyme ability to hydrolyze the starch a-1,4 glucosidic linkages, a characteristic behavior of an a-amylase.


Este estudo reporta a purificação e caracterização parcial de uma a-amilasa produzida por Penicillium commune mediante fermentação em fase sólida usando mandioca branca colombiana (Manihot esculenta Crantz) como suporte. A enzima foi purificada por precipitação fraccionada com sulfato de amónio, cromato-grafia de intercambio aniónico (DEAE-Sephadex A-50), cromatografia de filtração por gel (Sephadex G-75) e croma-tografia de intercambio catiónico (CM-Sephadex C-50) obtendo una actividade específica final de 314.82 U/mg, um grau de purificação na ordem de 62 e um rendimento de 9%. A purificação até à homogeneidade foi confirmada por SDS-PAGE. O peso molecular estimado foi de 35 kDa. A enzima mostrou máxima acti-vidade de hidrólises de amido solúvel a pH 6.0, e estabilidade num intervalo de pH de 5.0-7.0. A enzima foi estável num intervalo de temperatura de 0-50 °C, e sua temperatura óptima de reacção foi de 70°C. Íons Ca2+,Ba2+ eAg+ aumentaram significativamente a actividade da enzima, sendo o ião Ca2+, o que teve o mais alto poder indutor. Cu2+ não alterou significativamente a actividade da enzima, enquanto que Li+ eFe3+ a diminuíram ligeiramente (13%), e Co2+ eHg2+ a diminuíram 25% e40% respectivamente. Os valores de Km eVmáx foram calculados usando a linearização de Lineweaver-Burk, obtendo Km = 0.48 mg/mL e Vmáx = 5.85 µmol glucosa/min. Entre os principais produtos de hidrólises do amido de mandioca encontram-se a maltosa e glucosa; este resultado proporciona evidencia de que a enzima é capaz de romper os enlaces glucosídicos a-1,4 do amido, comportamento característico de uma a-amilasa.

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