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1.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1863(9): 1006-1015, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29859246

RESUMO

Talaromyces thermophilus lipase (TTL) was found to hydrolyze monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG) substrates presented in various forms to the enzyme. Different assay techniques were used for each substrate: pHstat with dioctanoyl galactolipid-bile salt mixed micelles, barostat with dilauroyl galactolipid monomolecular films spread at the air-water interface, and UV absorption using a novel MGDG substrate containing α-eleostearic acid as chromophore and coated on microtiter plates. The kinetic properties of TTL were compared to those of the homologous lipase from Thermomyces lanuginosus (TLL), guinea pig pancreatic lipase-related protein 2 and Fusarium solani cutinase. TTL was found to be the most active galactolipase, with a higher activity on micelles than on monomolecular films or surface-coated MGDG. Nevertheless, the UV absorption assay with coated MGDG was highly sensitive and allowed measuring significant activities with about 10 ng of enzymes, against 100 ng to 10 µg with the pHstat. TTL showed longer lag times than TLL for reaching steady state kinetics of hydrolysis with monomolecular films or surface-coated MGDG. These findings and 3D-modelling of TTL based on the known structure of TLL pointed out to two phenylalanine to leucine substitutions in TTL, that could be responsible for its slower adsorption at lipid-water interface. TTL was found to be more active on MGDG than on DGDG using both galactolipid-bile salt mixed micelles and galactolipid monomolecular films. These later experiments suggest that the second galactose on galactolipid polar head impairs the enzyme adsorption on its aggregated substrate.


Assuntos
Proteínas Fúngicas/química , Galactolipídeos/química , Lipase/química , Talaromyces/química , Ar/análise , Animais , Ácidos e Sais Biliares/química , Hidrolases de Éster Carboxílico/química , Ensaios Enzimáticos , Fusarium/química , Fusarium/enzimologia , Cobaias , Hidrólise , Cinética , Ácidos Linolênicos/química , Micelas , Modelos Moleculares , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Especificidade por Substrato , Propriedades de Superfície , Talaromyces/enzimologia , Raios Ultravioleta , Água/química
2.
Lipids Health Dis ; 16(1): 238, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29221452

RESUMO

BACKGROUND: Nutritional fact study has prime importance to make the species edible and commercially viable to the food consumers. This is the first report that indicates the chemical characterization, functional, antioxidant and antihypertensive properties of Cymodocea nodosa to evaluate its nutritional status. METHODS: Physico-chemical determination was determined by colorimetric and spectroscopic analysis. The functional and texture properties were evaluated since a desirable texture should be retained. Bioactive substances were determined by liquid chromatography-high resolution electrospray ionization mass spectrometry HPLC-DAD-ESI/MS2 analysis. Health benefit of this plant was highlighting by the antioxidant and antihypertensive potentials. RESULTS: Results showed that the seagrass powder was characterized by a high content of fibers (56.4%), the fatty acids profile was dominated by the oleic acid, which represents about 62.0% of the total fatty acids and the functional properties proved important values of swelling capacity (6.71 ± 0.2) and water holding capacity (12.26 ± 0.25), that were comparable to those of some foodstuffs. Finally, the physico-chemical analysis shows the wealth in phenolic compounds, that could be explained by the high antioxidant and antihypertensive ability which was concentration dependent. CONCLUSION: The results from this study suggested that this marine plant could be utilized as a healthy food item for human consumption.


Assuntos
Alismatales/química , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Anti-Hipertensivos/isolamento & purificação , Antioxidantes/isolamento & purificação , Ácidos Graxos/isolamento & purificação , Alimento Funcional/análise , Fenóis/isolamento & purificação , Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/química , Antioxidantes/química , Organismos Aquáticos , Compostos de Bifenilo/antagonistas & inibidores , Ácidos Graxos/química , Humanos , Peptidil Dipeptidase A/química , Fenóis/química , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Soluções
3.
Bioprocess Biosyst Eng ; 40(4): 559-571, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27988803

RESUMO

An extracellular ß-glucosidase from Fusaruim solani cultivated on wheat bran was purified by only two chromatographic steps. The purified enzyme exhibited optimal temperature and pH at 60 °C and pH 5, respectively. The purified ß-glucosidase behaves as a very large protein due to its high degree of glycosylation. More interestingly, the endoglycosidase H (Endo H) treatment led to 97.55% loss of its initial activity after 24 h of treatment. Besides, the addition of Tunicamycin (nucleoside antibiotic blocking the N-glycosylation first step) during the culture of the fungus affected seriously the glycosylation of the enzyme. Both treatments (endo H and Tunicamycin) strengthened the idea that the hyperglycosylation is involved in the ß-glucosidase activity and thermostability. This enzyme was also shown to belong to class III of ß-glucosidases (multi-specific) since it was able to act on either cellobiose, gentiobiose or sophorose which are disaccharide composed of two units of D-glucose connected by ß1-4, ß1-6 and ß1-2 linkage, respectively. The ß-glucosidase activity was strongly enhanced by ferrous ion (Fe2+) and high ionic strength (1 M KCl). The purified enzyme exhibited an efficient transglycosylation capacity allowing the synthesis of cellotriose and cellotetraose using cellobiose as donor.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Fusarium/enzimologia , beta-Glucosidase/química , beta-Glucosidase/isolamento & purificação , Proteínas Fúngicas/biossíntese , Glicosilação , beta-Glucosidase/biossíntese
4.
Prep Biochem Biotechnol ; 47(4): 414-423, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27824279

RESUMO

In the present study, we investigated a potent extracellular ß-glucosidases secreted by the thermophilic fungal strain AX4 of Talaromyces thermophilus, isolated from Tunisian soil samples. This strain was selected referring to the highest thermostability of its ß-glucosidases compared to the other fungal isolates. The ß-glucosidase production was investigated by submerged fermentation. The optimal temperature and initial pH for maximum ß-glucosidase production were 50°C and 7.0, respectively. Several carbon sources were assayed for their effects on ß-glucosidase production, significant yields were obtained in media containing lactose 1% (3.0 ± 0.36 U/ml) and wheat bran 2% (4.0 ± 0.4 U/ml). The combination of wheat bran at 2% and lactose at 0.8% as carbon source enhanced ß-glucosidase production, which reached 8.5 ± 0.28 U/ml. Furthermore, the ß-glucosidase-rich enzymatic juice of T. thermophilus exhibited significant synergism with Trichoderma reesei (Rut C30) cellulases for pretreated waste paper (PWP) hydrolysis. Interestingly, the use of this optimal enzymatic cocktail increased 4.23 fold the glucose yield after saccharification of waste paper. A maximum sugar yield (94%) was reached when using low substrate (2%) and enzyme loading (EC1).


Assuntos
Microbiologia Industrial/métodos , Papel , Eliminação de Resíduos/métodos , Talaromyces/enzimologia , beta-Glucosidase/metabolismo , Fibras na Dieta/metabolismo , Estabilidade Enzimática , Fermentação , Concentração de Íons de Hidrogênio , Hidrólise , Lactose/metabolismo , Microbiologia do Solo , Talaromyces/metabolismo , Temperatura
5.
Prep Biochem Biotechnol ; 47(2): 185-191, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-27340756

RESUMO

Fungal ß-glucosidases were extensively studied regarding their various potential biotechnology applications. Here, we report the selection of Fusarium solani strain producing high yield of ß-glucosidase activity. The effect of some factors on ß-glucosidase production was studied including: Initial pH, medium composition, concentration of carbon and nitrogen sources, and particle size of raw substrates. The optimal enzyme production was obtained with 4 units of pH. The highest ß-glucosidase activity was produced on 4% wheat bran (WB) as raw carbon sources, reaching 5 U/mL. A positive correlation between WB particle size and the ß-glucosidase production level was settled. The last one was enhanced to 13.60 U/mL in the presence of 0.5% (w/v) of ammonium sulfate. Interestingly, the activated charcoal was used as an inexpensive reagent enabling a rapid and efficient purification prior step that improved the enzyme-specific activity. Eventually, F. solani ß-glucosidase acts efficiently during the bioconversion process of oleuropein. Indeed, 82.5% of oleuropein was deglycosylated after 1 hr at 40°C. Altogether, our data showed that the ß-glucosidase of F. solani has a potential application to convert oleuropein to ameliorate food quality.


Assuntos
Carvão Vegetal/química , Fusarium/enzimologia , Iridoides/metabolismo , beta-Glucosidase/isolamento & purificação , Meios de Cultura , Concentração de Íons de Hidrogênio , Glucosídeos Iridoides , beta-Glucosidase/metabolismo
6.
J Ind Microbiol Biotechnol ; 43(7): 901-14, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27114386

RESUMO

Microbial lipids have drawn increasing attention in recent years as promising raw materials for biodiesel and added-value compounds production. To this end, new oleaginous yeast, Candida viswanathii Y-E4 was isolated, characterized and used for single cell oil (SCO) production. Physiologic and nutritional parameters optimization was carried out for improved biomass and lipid production. Y-E4 strain was able to use a wide range of substrates, especially C5 and C6 sugars as well as glycerol and hydrophobic substrates. The fatty acid profile analysis showed that oleic acid was the main component produced using different substrates. Batch and fed-bath fermentation were conducted using glucose as carbon source. Lipid production rate is twice higher in fed-batch culture providing a lipid content of 50 % (w/w). To minimize the SCO production cost, C. viswanathii Y-E4 was evaluated for its capacity to use different agro-industrial by-products for microbial oil production and changes in the fatty acid profile were monitored.


Assuntos
Candida/metabolismo , Lipídeos/biossíntese , Análise de Célula Única , Técnicas de Cultura Celular por Lotes , Biomassa , Reatores Biológicos/microbiologia , Candida/classificação , Candida/isolamento & purificação , Meios de Cultura/química , DNA Fúngico/isolamento & purificação , Ácidos Graxos/análise , Fermentação , Microbiologia Industrial , Ácido Oleico/análise , Filogenia
7.
Mar Drugs ; 11(12): 4724-40, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24287956

RESUMO

Severe toxicity was detected in mussels from Bizerte Lagoon (Northern Tunisia) using routine mouse bioassays for detecting diarrheic and paralytic toxins not associated to classical phytoplankton blooming. The atypical toxicity was characterized by rapid mouse death. The aim of the present work was to understand the basis of such toxicity. Bioassay-guided chromatographic separation and mass spectrometry were used to detect and characterize the fraction responsible for mussels' toxicity. Only a C17-sphinganine analog mycotoxin (C17-SAMT), with a molecular mass of 287.289 Da, was found in contaminated shellfish. The doses of C17-SAMT that were lethal to 50% of mice were 750 and 150 µg/kg following intraperitoneal and intracerebroventricular injections, respectively, and 900 µg/kg following oral administration. The macroscopic general aspect of cultures and the morphological characteristics of the strains isolated from mussels revealed that the toxicity episodes were associated to the presence of marine microfungi (Fusarium sp., Aspergillus sp. and Trichoderma sp.) in contaminated samples. The major in vivo effect of C17-SAMT on the mouse neuromuscular system was a dose- and time-dependent decrease of compound muscle action potential amplitude and an increased excitability threshold. In vitro, C17-SAMT caused a dose- and time-dependent block of directly- and indirectly-elicited isometric contraction of isolated mouse hemidiaphragms.


Assuntos
Bivalves/química , Toxinas Marinhas/química , Micotoxinas/química , Micotoxinas/toxicidade , Paralisia/induzido quimicamente , Esfingosina/análogos & derivados , Animais , Bioensaio/métodos , Camundongos , Frutos do Mar , Intoxicação por Frutos do Mar , Esfingosina/química , Esfingosina/toxicidade , Tunísia
8.
Appl Biochem Biotechnol ; 194(6): 2700-2719, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35244858

RESUMO

Talaromyces thermophilus galactolipase (TTL) was found to produce alcohol sugar fatty acid diesters. The modulation of the solvent composition was used for the esterification reaction screening of diesters from xylitol and various fatty acids using the immobilized Talaromyces thermophilus galactolipase. The reactions were assessed by LC-MS analysis. The antimicrobial activity assay showed that both xylitol dicaprylate and xylitol dilaurate esters had more ability to inhibit the growth of several bacteria involved in surface contamination in the food industry. The xylitol dilaurate ester has the highest activity against Gram-positive strains with the lowest MIC values of 0.0016 and 0.005 mg mL-1 against Bacillus licheniformis and Staphylococcus aureus, respectively. Xylitol dicaprylate ester is more active against Gram-negative ones with significantly low MIC values of 0.25 and 0.4 mg mL-1 against Escherichia coli and Pseudomonas aeruginosa, respectively. The highest antifungal activity of the xylitol dicaprylate ester has been also proven, with a MIC value of 0.02 mg mL-1 against Penicillium occitanis and Fusarium solani. A better reduction in critical micelle concentrations and air-water surface tension were observed with these diesters compared to their corresponding monoesters in addition to their efficient emulsifying properties. The stability of these diesters in a liquid detergent formula after one year of storage was tested by a positive oil spreading assay and a retained antimicrobial activity. They exhibit a typical surfactant behavior with a two-in-one effect that can act as a detergent and a disinfectant with potential use in different cleaning processes.


Assuntos
Desinfetantes , Ésteres , Hidrolases de Éster Carboxílico , Detergentes , Eurotiales , Ácidos Graxos , Testes de Sensibilidade Microbiana , Tensoativos/farmacologia , Xilitol
9.
Acta Chim Slov ; 68(3): 575-586, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34897543

RESUMO

This work mainly focused on the production of an efficient, economical, and eco-friendly lipase (AKL29) from Actinomadura keratinilytica strain Cpt29 isolated from poultry compost in north east of Algeria, for use in detergent industries. AKL29 shows a significant lipase activity (45 U/mL) towards hydrolyzed triacylglycerols, indicating that it is a true lipase. For maximum lipase production the modeling and optimization of potential culture parameters such as incubation temperature, cultivation time, and Tween 80 (v/v) were built using RSM and ANN approaches. The results show that both the two models provided good quality predictions, yet the ANN showed a clear superiority over RSM for both data fitting and estimation capabilities. A 4.1-fold increase in lipase production was recorded under the following optimal condition: incubation temperature (37.9 °C), cultivation time (111 h), and Tween 80 (3.27%, v/v). Furthermore, the partially purified lipase showed good stability, high compatibility, and significant wash performance with various commercial laundry detergents, making this novel lipase a promising potential candidate for detergent industries.


Assuntos
Actinomadura/enzimologia , Proteínas de Bactérias/química , Detergentes/química , Lipase/química , Proteínas de Bactérias/isolamento & purificação , Estabilidade Enzimática , Proteínas Fúngicas/química , Cinética , Lipase/isolamento & purificação , Redes Neurais de Computação , Saccharomycetales/enzimologia , Triglicerídeos/química
10.
Appl Microbiol Biotechnol ; 85(5): 1361-72, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19697020

RESUMO

This study is an application of an experimental design methodology for the optimization of the culture conditions of alpha-L: -arabinofuranosidase production by Talaromyces thermophilus. Wheat bran and yeast extract were first selected as the best carbon and nitrogen sources, respectively, for enzyme production. A Plackett-Burman design was then used to evaluate the effects of eight variables. Statistical analyses showed that while pH had a negative effect on alpha-L: -arabinofuranosidase production, wheat bran and MgSO(4) had a significantly positive effect. The values of the latter three parameters were further optimised using a central composite design and a response surface methodology. The experimental results were fitted to a second-order polynomial model that yielded a determination coefficient of R(2) = 0.91. The statistical output showed that the linear and quadric terms of the three variables had significant effects. Using optimal conditions, the experimental value of alpha-L: -arabinofuranosidase activity produced was very close to the model-predicted value. The optimal temperature and pH of enzyme activity were 55 degrees C and 7.0, respectively. This enzyme was very stable over a considerable pH range from 4 to 9. The crude enzyme of T. thermophilus rich in alpha-L: -arabinofuranosidase was also used for saccharification of lignocellulosic materials and arabinose production.


Assuntos
Glicosídeo Hidrolases/biossíntese , Microbiologia Industrial/métodos , Talaromyces/enzimologia , Arabinose/metabolismo , Reatores Biológicos , Carbono/metabolismo , Meios de Cultura/química , Fibras na Dieta , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Fermentação , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Sulfato de Magnésio/metabolismo , Modelos Biológicos , Modelos Estatísticos , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Polissacarídeos/metabolismo , Temperatura
11.
Waste Manag Res ; 28(9): 828-37, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20022900

RESUMO

Actinomycetes with the ability to degrade natural polysaccharides were isolated during a screening programme from soil, farmyard manure and municipal solid waste compost. One of the most potent isolates was identified as Streptomyces sp. MSWC1 using morphological and biochemical properties along with 16S rDNA partial sequence analysis. The highest enzyme production by Streptomyces was observed for the xylanase and chitinase activity on different carbon sources with an optimum of 12,100 IU ml(-1) and 110 IU ml(-1) at 3 days' culture on 1% of xylan and chitin, respectively. To meet the demand of industry, low-cost medium is required for the production of hydrolases by Streptomyces sp. Strain MSWC1 grown on manure, compost, and a natural carbon source was used to evaluate the re-utilisation of biological wastes for the production of value-added products. Despite the presence of a high amount of toxic heavy metals in the compost, Streptomyces produced interesting enzymes that have been biochemically characterized.


Assuntos
Hidrolases/biossíntese , Eliminação de Resíduos/métodos , Streptomyces/metabolismo , Sequência de Bases , Biodegradação Ambiental , Cidades , Dados de Sequência Molecular , Streptomyces/genética , Streptomyces/isolamento & purificação
12.
Biomed Res Int ; 2019: 3213521, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31915687

RESUMO

The lignocellulosic hydrolysate was used as the fermentation feedstock of Rhodotorula mucilaginosa Y-MG1 for the production of microbial lipids as the potential raw material for biodiesel synthesis. On synthetic media and under nitrogen-limiting condition, the Y-MG1 strain produces 2.13 g/L of lipids corresponding to 32.7% of lipid content. This strain was able to assimilate a wide range of substrates, especially C5 and C6 sugars as well as glycerol and sucrose. Fatty acid composition shows a divergence depending on the nature of used carbon source with a predominance of oleic acid or linoleic acid. An effective hydrolysis process, based on diluted acid treatment, was established for providing the maximum of fermentable sugars from different characterized lignocellulosic wastes. The highest yield of reducing sugars (56.6 g/L) could be achieved when wheat bran was used as the raw material. Hydrolysate detoxification step was not required in this study since the Y-MG1 strain was shown to grow and produce lipids in the presence of inhibitors and without the addition of external elements. Operating by controlled fed-batch fermentation yielded a dry biomass and oil yield of up to 11 g/L and 38.7% (w/w), respectively. The relative fatty acid composition showed the presence of increased levels of monounsaturated (66.8%) and saturated (23.4%) fatty acids in lipids of Y-MG1 grown on wheat bran. The predictive determination of biodiesel properties suggests that this oil may effectively be used for biodiesel production.


Assuntos
Biocombustíveis , Fibras na Dieta/metabolismo , Ácidos Graxos/análise , Lipídeos/biossíntese , Rhodotorula/metabolismo , Biomassa , Fermentação , Glicerol/metabolismo , Hidrólise , Ácido Linoleico/metabolismo , Ácido Oleico/metabolismo , Sacarose/metabolismo
13.
Bioresour Technol ; 273: 326-334, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30448685

RESUMO

The newly isolated oleaginous yeast, Rhodotorula babjevae Y-SL7, was shown to accumulate high intracellular content of microbial oil (mainly triacylglycerols) and to secret, under the same culture conditions, an atypical glycolipid. This unusual behavior was induced when the strain was subjected to nitrogen limitation and high amount of carbon. A series of analytical methods was adopted in order to structurally characterize the secreted glycolipid. The latter consists of a mixture of 9 molecules formed by a polyol head group, bound through the carboxyl end of an acetylated 3-hydroxy fatty acid with C18 or C16 chain length. In addition of their physicochemical properties such as emulsifying activity on hydrophobic substrates, Y-SL7 glycolipids have shown a therapeutically promising cytotoxic effect against different cancer cell lines. In fact, Y-SL7 strain can be used for the production of triacylglycerols as energetic molecules and for the secretion of a biosurfactant of therapeutic and environmental interest.


Assuntos
Glicolipídeos/metabolismo , Rhodotorula/metabolismo , Triglicerídeos/biossíntese , Biotecnologia , Ácidos Graxos/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Nitrogênio/metabolismo
14.
Appl Biochem Biotechnol ; 150(3): 267-79, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18592411

RESUMO

When grown on wheat bran as the only carbon source, the filamentous fungus Talaromyces thermophilus produces large amounts of beta-xylosidase activity. The presence of glucose drastically decreases the beta-xylosidase production level. The beta-xylosidase of T. thermophilus was purified by ammonium sulfate precipitation, DEAE-cellulose chromatography, and gel filtration (high-performance liquid chromatography). The molecular mass of the enzyme was estimated to be 97 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration. The enzyme activity was optimum at 50 degrees C and pH 7. The apparent Michaelis constant K(m) of the beta-xylosidase was 2.37 mM for p-nitrophenyl-beta-D-xylopyranoside, with a V(max) of 0.049 micromol min(-1) per milligram protein. Enzyme activity was inhibited by Cu(2+), Hg(2+), and Zn(2+) and activated by Ca(2+), Mn(2+), and Co(+) at a concentration of 5 mM. At high xylose concentration, this enzyme catalyses the condensation reaction leading to xylobiose production.


Assuntos
Dissacarídeos/biossíntese , Proteínas Fúngicas/metabolismo , Talaromyces/enzimologia , Xilosidases/metabolismo , Cálcio/farmacologia , Cromatografia , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cobalto/farmacologia , Cobre/farmacologia , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática/efeitos dos fármacos , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Manganês/farmacologia , Mercúrio/farmacologia , Peso Molecular , Talaromyces/efeitos dos fármacos , Temperatura , Xilosidases/química , Xilosidases/isolamento & purificação , Zinco/farmacologia
15.
Data Brief ; 16: 386-391, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29234697

RESUMO

The data presented in this article are related to the research article titled "Immobilization nd topochemical mechanism of a new ß-amylase extracted from Pergularia tomentosa" (Lahmar et al., 2017) [1]. This article documented information on the determination of the molecular weight of the ß-amylase, the method of its immobilization and a comparison of the kinetic mechanism between the free and the immobilized forms by a mathematical method. Fresh Pergularia tomentosa was collected from Tunisia and a special method for ß-amylase extraction was followed (Yotova et al., 2000) [2]. Public dissemination of this dataset will allow further analyses of the data.

16.
Biomed Res Int ; 2017: 6903817, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28409159

RESUMO

Crude extracts from a medicinal Tunisian plant, Pergularia tomentosa L., were the investigated natural material. Butanolic extract of roots analyzed with IR spectra revealed the presence of hydroxyl, alcoholic, and carboxylic groups and sugars units. Analysis of some secondary metabolites, total phenolic, flavonoids, flavonols, and procyanidins, was performed using different solvents following the increased gradient of polarity. Fruits and leaves contained the highest amounts of all these compounds. Antioxidant properties were evaluated by the determination of free radical scavenging activity and the reducing power of methanolic extracts. Fruits and leaf extracts were the most powerful antioxidants for the two-assay in vitro system. Stems and fruits extracts exhibit an antifungal activity against Fusarium oxysporum f. sp. lycopersici which could become an alternative to synthetic fungicide to control Solanum species fungal diseases.


Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Fusariose/tratamento farmacológico , Extratos Vegetais/farmacologia , Antifúngicos/química , Antioxidantes/química , Apocynaceae/química , Fusariose/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/patogenicidade , Humanos , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Plantas Medicinais/química , Solventes/química
17.
Int J Biol Macromol ; 103: 543-553, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28527996

RESUMO

This work aims at realizing an optimal hydrolysis of pretreated Alfa fibers (Stipa tenacissima) through the use of enzymes produced from Talaromyces thermophilus AX4, namely ß-d-glucosidase and xylanase, by a solid state fermentation process of an agro-industrial waste (wheat bran supplemented with lactose). The carbon source was firstly selected and the optimal values of three other parameters were determined: substrate loading (10g), moisture content (85%) and production time (10days); which led to an optimized enzymatic juice. The outcome was then supplemented with cellulases of T. reesei and used to optimize the enzymatic saccharification of alkali-pretreated Alfa fibers (PAF). The maximum saccharification yield of 83.23% was achieved under optimized conditions (substrate concentration 3.7% (w/v), time 144h and enzyme loading of 0.8 FPU, 15U CMCase, 60U ß-d-glucosidase and 125U xylanase).The structural modification of PAF due to enzymatic saccharification was supported by the changes of morphologic and chemical composition observed through macroscopic representation, FTIR and X-Ray analysis.


Assuntos
Biotecnologia , Endo-1,4-beta-Xilanases/metabolismo , Fermentação , Poaceae/química , Talaromyces/enzimologia , beta-Glucosidase/metabolismo , Fibras na Dieta/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Resíduos Industriais , Cinética , Lactose/metabolismo
18.
Biomed Res Int ; 2017: 6712742, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29392138

RESUMO

A continuous research is attempted to fulfil the highest industrial demands of natural amylases presenting special properties. New α-amylases extracted from stems and leaves of Pergularia tomentosa, which is widespread and growing spontaneously in Tunisia, were studied by the means of their activities optimization and purification. Some similarities were recorded for the two identified enzymes: (i) the highest amylase activity showed a promoted thermal stability at 50°C; (ii) the starch substrate at 1% enhanced the enzyme activity; (iii) the two α-amylases seem to be calcium-independent; (iv) Zn2+, Cu2+, and Ag2+ were considered as important inhibitors of the enzyme activity. Following the increased gradient of elution on Mono Q-Sepharose column, an increase in the specific activity of 11.82-fold and 10.92-fold was recorded, respectively, for leaves and stems with the presence of different peaks on the purification profiles. Pergularia amylases activities were stable and compatible with the tested commercial detergents. The combination of plant amylase and detergent allowed us to enhance the wash performance with an increase of 35.24 and 42.56%, respectively, for stems and leaves amylases. Characterized amylases were reported to have a promoted potential for their implication notably in detergent industry as well as biotechnological sector.


Assuntos
Apocynaceae/enzimologia , Inibidores Enzimáticos/química , alfa-Amilases/química , alfa-Amilases/isolamento & purificação , Apocynaceae/química , Cálcio/química , Cobre/química , Detergentes/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Folhas de Planta/enzimologia , Caules de Planta/enzimologia , Prata/química , Amido/química , Temperatura , Zinco/química , alfa-Amilases/antagonistas & inibidores
19.
Arch Physiol Biochem ; 123(1): 31-42, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27855503

RESUMO

The present study investigated the effect of the Cystoseira crinita sulfated polysaccharide (CCSP) on key enzymes activities related to diabetes in vitro and in diabetic rats. We found that CCSP inhibited pancreatic α-amylase with IC50 = 39.16 µg/ml and angiotensin I-converting enzyme (ACE) activity with IC50 = 58.35 µg/ml in vitro. In diabetic rats, the administration of CCSP reduced the activity of α-amylase in serum, pancreas, and intestine by 23%, 44.38%, and 45%, respectively as compared to untreated diabetic rats. Moreover, the administration of CCSP to surviving diabetic rats protects pancreas ß cells from death and damage, which leads to insulin levels. The decrease in α-amylase and the increase in insulin level lead to a decrease in glucose rate by 56% as compared to untreated diabetic rats. The inhibitory action of α-amylase activity and hypoglycemic effect of CCSP were confirmed by oral glucose tolerance test (OGTT). In addition, the administration of CCSP to surviving diabetic rats normalizes lipid profile, stimulates antioxidant capacity, and prevents liver-kidney toxicities, evidenced by decrease in serum indices of liver and kidney toxicity and confirmed by histological analysis. The overall findings presented in this study demonstrate that the administration of CCSP to diabetic rats can make it a potentially strong candidate for industrial application as a pharmacological agent for the treatment of hyperglycemia, hyperlipidemia, and liver-kidney dysfunctions.


Assuntos
Anti-Hipertensivos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Phaeophyceae/química , Polissacarídeos/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Anti-Hipertensivos/química , Anti-Hipertensivos/isolamento & purificação , Anti-Hipertensivos/metabolismo , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/metabolismo , Hipertensão/metabolismo , Hipertensão/patologia , Hipertensão/fisiopatologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/enzimologia , Intestino Delgado/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Masculino , Mar Mediterrâneo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , alfa-Amilases Pancreáticas/antagonistas & inibidores , alfa-Amilases Pancreáticas/sangue , alfa-Amilases Pancreáticas/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Phaeophyceae/crescimento & desenvolvimento , Polissacarídeos/química
20.
Biomed Pharmacother ; 85: 517-526, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27903424

RESUMO

The objective of this current study was to investigate the possible hyperlipidemic and antioxidative effects of Cystoseira crinita sulfated polysaccharide (CCSP) in rats fed with a high-fat diet, exhibited an inhibitory activity on pancreatic lipase in vitro. In vivo administration of this extract to HFD-rats lowered body weight and potentially inhibited key enzymes of lipid metabolism and absorption as lipase activity in both plasma and small intestine, which led to a notable decrease of blood LDL- cholesterol (LDL-Ch) and triglycerides (TG) levels, and an increase in HDL-cholesterol (HDL-Ch) levels in HFD-rats. CCSP was also observed to protect the liver-kidney functions efficiently, by decreasing of aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH) and Creatine phosphokinase (CPK) activities and creatinine, albumin, T-bilirubin, uric acid, and urea rates in plasma. The histological analysis of liver and kidney tissues further established the positive effect of CCSP.


Assuntos
Gorduras na Dieta/farmacologia , Hiperlipidemias/tratamento farmacológico , Phaeophyceae/química , Extratos Vegetais/química , Polissacarídeos/farmacologia , Animais , Gorduras na Dieta/administração & dosagem , Digestão/efeitos dos fármacos , Digestão/fisiologia , Relação Dose-Resposta a Droga , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Polissacarídeos/administração & dosagem , Ratos , Ratos Wistar
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