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1.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38543170

RESUMEN

Ammodaucus leucotrichus exhibits promising pharmacological activity, hinting at anti-inflammatory and anti-arthritic effects. This study investigated seed extracts from Ammodaucus leucotrichus using methanol and n-hexane, focusing on anti-inflammatory and anti-arthritic properties. The methanol extract outperformed the n-hexane extract and diclofenac, a reference anti-inflammatory drug, in trypsin inhibition (85% vs. 30% and 64.67% at 125 µg/mL). For trypsin inhibition, the IC50 values were 82.97 µg/mL (methanol), 202.70 µg/mL (n-hexane), and 97.04 µg/mL (diclofenac). Additionally, the n-hexane extract surpassed the methanol extract and diclofenac in BSA (bovine serum albumin) denaturation inhibition (90.4% vs. 22.0% and 51.4% at 62.5 µg/mL). The BSA denaturation IC50 values were 14.30 µg/mL (n-hexane), 5408 µg/mL (methanol), and 42.30 µg/mL (diclofenac). Gas chromatography-mass spectrometry (GC-MS) revealed 59 and 58 secondary metabolites in the methanol and n-hexane extracts, respectively. The higher therapeutic activity of the methanol extract was attributed to hydroxyacetic acid hydrazide, absent in the n-hexane extract. In silico docking studies identified 28 compounds with negative binding energies, indicating potential trypsin inhibition. The 2-hydroxyacetohydrazide displayed superior inhibitory effects compared to diclofenac. Further mechanistic studies are crucial to validate 2-hydroxyacetohydrazide as a potential drug candidate for rheumatoid arthritis treatment.

2.
Biol Trace Elem Res ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38060173

RESUMEN

Modification of catalytic expression of enzymes and regulating their in vivo activity are the goals of novel treatment strategies. A green synthetic nanostructured silver with potent trypsin inhibitory properties has not yet been developed, despite the fact that silver nanoparticles possess unique properties that allow them to efficiently block enzymes. The present study demonstrates for the first time a facile, safe, economic, and eco-friendly synthetic route for silver nanoparticles using an aqueous extract of Holigarna arnottiana bark engineered to interact with trypsin and hinder its activity effectively. The studies carried out to examine the interaction between these biofabricated AgNPs (HaAgNPs) and trypsin by UV-visible spectrophotometry and FTIR spectroscopy suggest that the formation of trypsin-HaAgNP complex is responsible for diminishing the catalytic efficiency of trypsin. In vivo studies on Aedes aegypti larval serum support these instrumental results of HaAgNP-induced trypsin inhibition and proves its application as a biopesticide. It is noteworthy that the bioengineered HaAgNPs were also found to have good inhibition potential against pepsin and urease as well. A variety of methods have been employed to characterize the synthesized biocompatible HaAgNPs and it possesses a characteristic absorption maximum of 420 nm. Their shelf life of above 7 years is noticeable, since none of the reported green synthesized AgNPs possess a shelf life of more than 1 year. Altogether, this work demonstrates that biofabricated HaAgNPs are multifunctional and cost-resilient biological tools that can be used as enzyme regulators possessing antioxidant, antimicrobial, and insecticidal features.

3.
J Econ Entomol ; 116(6): 2146-2153, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37816687

RESUMEN

Lepidopteran pests have been successfully managed by the adoption of insect resistant transgenic plants expressing Cry and/or Vip insecticidal proteins derived from Bacillus thuringiensis (Bt plants). Among such pests, Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) is highlighted for its destructive potential in maize crops and for cases of field-evolved resistance to Bt plants. Cry insecticidal proteins expressed in Bt plants are known for their interaction with insect midgut receptors and subsequent midgut cell disruption that leads to target pest death. In the midgut of lepidopteran larval pests such as S. frugiperda, serine proteases are important in dietary protein digestion and activation or degradation of insecticidal proteins. This work was conducted to evaluate if the use of a soybean trypsin inhibitor (SBTI) could disrupt the development of a Bt-susceptible and a Bt-resistant population of S. frugiperda ingesting Bt (expressing Cry1F, Cry1A.105, and Cry2Ab2 Cry proteins) and non-Bt maize plants. The SBTI was produced and purified using recombinant expression in E. coli followed by purification in Ni-Sepharose. Bioassays using non-Bt maize leaves indicated that the development of susceptible and resistant populations of S. frugiperda was not influenced by the ingestion of SBTI. However, when the resistant population consumed Bt maize plants amended with SBTI, high mortality along with a reduction in larval weight and reduced activity of digestive trypsins were observed. Although the mode of action was not elucidated, it is possible that the consumption of SBTI increased susceptibility to Bt maize in the resistant population of S. frugiperda.


Asunto(s)
Bacillus thuringiensis , Insecticidas , Animales , Spodoptera , Zea mays , Inhibidores de Tripsina/farmacología , Glycine max/genética , Endotoxinas/farmacología , Escherichia coli/metabolismo , Toxinas de Bacillus thuringiensis , Resistencia a los Insecticidas , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/genética , Insecticidas/farmacología , Bacillus thuringiensis/genética , Larva/fisiología , Plantas Modificadas Genéticamente/genética
4.
Int J Biol Macromol ; 253(Pt 8): 127581, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37884242

RESUMEN

Massa Medicata Fermentata (MMF) is a traditional Chinese medicine widely used in feed additives and human medicine. In this study, two neutral polysaccharides (SMMFP-1 and CMMFP-1) were isolated from two forms of MMF (sheng and chao MMF), and their structural characteristics and bioactivities were studied. The results showed that CMMFP-1 had higher average Mw compared with that of SMMFP-1. SMMFP-1 had a lower proportion of Ara, Xyl, GalA, and GlcA, but higher levels of Fuc, Gal, Man, and GulA. Compared with CMMFP-1, SMMFP-1 had a triple helix structure. SMMFP-1 had a layered structure, whereas CMMFP-1 had a curly layered structure. More glycosidic linkage types were found in SMMFP-1 than in CMMFP-1, and SMMFP-1 had a greater number of side chains. More importantly, SMMFP-1 showed better trypsin inhibition activity in vitro, liver-protective activity in vivo, and stronger antioxidant activity in vivo than CMMFP-1. Thus, arabinoxylans may be one of the active substances for different efficacies between MMF and its processed product. The results of this study facilitate the exploration of the correlation between the structural characteristics and biological functionalities of MMF arabinoxylans. Moreover, a theoretical basis is established for further study of the unique properties of arabinoxylans and their applications.


Asunto(s)
Antioxidantes , Hígado , Masculino , Humanos , Antioxidantes/farmacología , Tripsina , Fermentación , Polisacáridos
5.
Heliyon ; 8(10): e10878, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36247161

RESUMEN

Soybean (Glycine max) is a superior plant food known as the miracle golden bean due to its treasure trove of inexpensive and superior protein to high-priced meat protein. Tofu is typically thought of as a salt or acid-coagulated water-based gel containing soy lipids and proteins trapped within its gel networks. Sprouted tofu is easier to digest and contains more nutrients than regular tofu. The purpose of this study was to evaluate the nutritional and sensory quality of tofu. The study was concerned with the preparation of tofu from non-germinated and germinated soybeans of 0 (T0), 2 (T1), 4 (T2) and 6 (T3) days. The length of the radicle was 0.8, 1.5, and 2 inches for T1, T2, and T3, respectively. Lipoxygenase activity, phytate inhibitory activity, urease activity, trypsin inhibitory activity, protein solubility, nutritional, and sensory quality of prepared tofu were all assessed. Longer sprouting times reduced phytate, urease, trypsin, and lipoxygenase activity while increasing protein solubility. Tofu prepared from T3 showed significantly better physicochemical properties than others. Protein, ash, and fat contents were significantly higher in T3. The level of nutrient content for tofu samples was in the rank of T3>T2>T1>T0. The L∗, a∗ and b∗ values were followed the same ranked as nutrient content (T3>T2>T1>T0). Sensory characteristics indicated that T3 was significantly more acceptable to the panelist. This study concludes that tofu made from 6 day sprouted soybeans with a height of 2 inches can be a good source of nutrition for consumers.

6.
J Microbiol ; 60(1): 89-99, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34964945

RESUMEN

The poor stability of peptides against trypsin largely limits their development as potential antibacterial agents. Here, to obtain a peptide with increased trypsin stability and potent antibacterial activity, TICbf-14 derived from the cationic peptide Cbf-14 was designed by the addition of disulfide-bridged hendecapeptide (CWTKSIPPKPC) loop. Subsequently, the trypsin stability and antimicrobial and antibiofilm activities of this peptide were evaluated. The possible mechanisms underlying its mode of action were also clarified. The results showed that TICbf-14 exhibited elevated trypsin inhibitory activity and effectively mitigated lung histopathological damage in bacteria-infected mice by reducing the bacterial counts, further inhibiting the systemic dissemination of bacteria and host inflammation. Additionally, TICbf-14 significantly repressed bacterial swimming motility and notably inhibited biofilm formation. Considering the mode of action, we observed that TICbf-14 exhibited a potent membrane-disruptive mechanism, which was attributable to its destructive effect on ionic bridges between divalent cations and LPS of the bacterial membrane. Overall, TICbf-14, a bifunctional peptide with both antimicrobial and trypsin inhibitory activity, is highly likely to become an ideal candidate for drug development against bacteria.


Asunto(s)
Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/enzimología , Proteínas Bacterianas/antagonistas & inhibidores , Biopelículas/efectos de los fármacos , Inhibidores de Tripsina/farmacología , Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/química , Proteínas Bacterianas/metabolismo , Diseño de Fármacos , Pruebas de Sensibilidad Microbiana , Tripsina/química , Tripsina/metabolismo , Inhibidores de Tripsina/química
7.
J Basic Microbiol ; 61(8): 709-720, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34228389

RESUMEN

Trypsin is a protein-digesting enzyme that is essential for the growth and regeneration of bone, muscle, cartilage, skin, and blood. The trypsin inhibitors have various role in diseases such as inflammation, Alzheimer's disease, pancreatitis, rheumatoid arthritis, cancer prognosis, metastasis and so forth. From 10 endophytic fungi isolated, we were able to screen only one strain with the required activity. The fungus with activity was obtained as an endophyte from Dendrophthoe falcata and was later identified as Nigrospora sphaerica. The activity was checked by enzyme assays using trypsin. The fungus was fermented and the metabolites were extracted and further purified by bioassay-guided chromatographic methods and the compound isolated was identified using gas chromatography-mass spectrometry. The compound was identified as quercetin. Docking studies were employed to study the interaction. The absorption, distribution, metabolism, and excretion analysis showed satisfactory results and the compound has no AMES and hepatotoxicity. This study reveals the ability of N. sphaerica to produce bioactive compound quercetin has been identified as a potential candidate for trypsin inhibition. The present communication describes the first report claiming that N. sphaerica strain AVA-1 can produce quercetin and it can be considered as a sustainable source of trypsin active-site inhibitors.


Asunto(s)
Ascomicetos/metabolismo , Inhibidores de Tripsina/química , Inhibidores de Tripsina/aislamiento & purificación , Tripsina/metabolismo , Antioxidantes , Endófitos/metabolismo , Fermentación , Loranthaceae , Simulación del Acoplamiento Molecular , Inhibidores de Tripsina/metabolismo , Inhibidores de Tripsina/farmacología
8.
BMC Plant Biol ; 21(1): 113, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33627080

RESUMEN

BACKGROUND: Recent studies indicate that amylase-trypsin inhibitors (ATIs) and certain carbohydrates referred to as FODMAPs (fermentable oligo-, di-, monosaccharides and polyols) play an important role in promoting wheat sensitivity. Hitherto, no study has investigated the accumulation of ATIs during the development of the wheat caryopsis. We collected caryopses of common wheat cv. 'Arnold' at eight different grain developmental stages to study compositional changes in ATI and FODMAP content. RESULTS: The harvested caryopses were analysed for their size, protein and carbohydrate concentrations. ATIs were further characterized by MALDI-TOF MS, and their trypsin inhibition was evaluated by an enzymatic assay. The results showed that ATI accumulation started about 1 week after anthesis and subsequently increased steadily until physiological maturity. However, the biological activity of ATIs in terms of enzyme inhibition was not detectable before about 4 weeks after anthesis. Carbohydrate analysis revealed the abundance of short-chain fructans in early stages of grain development, whereas non-water-soluble carbohydrates increased during later developmental stages. CONCLUSIONS: The results provide new insights into the complex metabolisms during grain filling and maturation, with particular emphasis on the ATI content as well as the inhibitory potential towards trypsin. The time lag between ATI accumulation and development of their biological activity is possibly attributed to the assembling of ATIs to dimers and tetramers, which seems to be crucial for their inhibitory potential.


Asunto(s)
Amilasas/metabolismo , Grano Comestible/crecimiento & desarrollo , Inhibidores Enzimáticos/metabolismo , Semillas/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Inhibidores de Tripsina/metabolismo , Tripsina/metabolismo , Austria , Metabolismo de los Hidratos de Carbono
9.
Recent Pat Food Nutr Agric ; 10(1): 57-61, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29984666

RESUMEN

BACKGROUND: Recent patents reveal that vegetable ingredients have several applications in novel food formulations. Many so-called antinutritional components (e.g. tannins, saponins, lectins and protease inhibitors) have nutraceutical as well as pharmaceutical significance. Seeds of two wild legumes of the genus Canavalia inhabitants of the coastal sand dunes of Southwest India are known for a variety of bioactive principles (e.g. phenolics, tannins, canavanine, concanavalin and phytohemagglutinins). OBJECTIVE: This study evaluates the impact of Electron Beam (EB) irradiation on the bioactive components of seeds of two coastal sand dune wild legumes Canavalia cathartica and C. maritima. METHODS: The dry seeds of C. cathartica and C. maritima were EB irradiated with different doses (2.5, 5, 10 and 15 kGy) to follow changes in six bioactive principles (total phenolics, orthodihydric phenols, tannins, canavanine, trypsin inhibitors and phytohemagglutinins) in comparison to control seeds. One-way ANOVA was employed to follow the variation in bioactive components of seeds in control and different doses of irradiation. RESULTS: Seeds of both legumes were devoid of orthodihydric phenols and trypsin inhibitors. In C. cathartica, the total phenolics showed significant dose-dependent increase up to 5 kGy and decreased thereafter. Tannin content was not altered up to 10 kGy followed by significant decrease at 15 kGy. There was no significant change in canavanine content and the phytohemagglutinin activity against human erythrocytes was not altered. Seeds of C. maritima did not show significant changes in total phenolics as well as tannin contents. The content of canavanine showed significant dose-dependent increase up to 5 kGy followed by significant decrease. There was no variation in phytohemagglutinin activity against erythrocytes A, B and O, while against AB, the activity decreased at 2.5 kGy and further decrease was constant at higher doses. CONCLUSION: The EB irradiation doses employed have selectively altered the bioactive principles of Canavalia seeds and such treatments may facilitate to maneuver desired medicinal, nutritional, functional and cooking properties. Besides selective changes in bioactive components the seeds have extended shelf life.


Asunto(s)
Canavalia/efectos de la radiación , Tubo de Rayos Catódicos , Tecnología de Alimentos/métodos , Semillas/efectos de la radiación
10.
Fish Shellfish Immunol ; 83: 308-313, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30219384

RESUMEN

The present study investigated the effects of 25 and 50% dietary inclusion of yellow mealworm, Tenebrio molitor (TM), larvae on the intestinal antioxidant enzymes, lipid peroxidation and immune system of rainbow trout, Oncorhynchus mykiss. Fish were fed for 90 days with a control diet (TM0) or with 2 test diets (TM25 and TM50) where 35 and 67% of the fishmeal was replaced by TM larvae meal respectively. At the end of the growth trial, humoral immune parameters were assessed in the sera of the fish and the activities of antioxidant enzymes were measured in intestine homogenates. The present results show a strong increase of the activity of the antioxidant intestinal enzymes and reduction of lipid peroxidation. Increased trypsin inhibition and faster antibacterial activity of the serum were also detected. These evidences could be due to the physiological similarities between the exoskeleton of parasites and insects. The present findings reinforce the previous results which revealed a positive effect of the dietary TM on rainbow trout growth and further confirm its adequacy for fishmeal partial replacement in aquafeed.


Asunto(s)
Suplementos Dietéticos , Larva , Oncorhynchus mykiss/inmunología , Tenebrio , Animales , Dieta/veterinaria , Proteínas de Peces/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Inmunidad Innata , Intestinos/enzimología , Oncorhynchus mykiss/metabolismo , Superóxido Dismutasa/metabolismo
11.
Planta ; 245(2): 343-353, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27778107

RESUMEN

MAIN CONCLUSION: A new BBI-type protease inhibitor with remarkable structural characteristics was purified, cloned, and sequenced from seeds of Maclura pomifera , a dicotyledonous plant belonging to the Moraceae family. In this work, we report a Bowman-Birk inhibitor (BBI) isolated, purified, cloned, and characterized from Maclura pomifera seeds (MpBBI), the first of this type from a species belonging to Moraceae family. MpBBI was purified to homogeneity by RP-HPLC, total RNA was extracted from seeds of M. pomifera, and the 3'RACE-PCR method was applied to obtain the cDNA, which was cloned and sequenced. Peptide mass fingerprinting (PMF) analysis showed correspondence between the in silico-translated protein and MpBBI, confirming that it corresponds to a new plant protease inhibitor. The obtained cDNA encoded a polypeptide of 65 residues and possesses 10 cysteine residues, with molecular mass of 7379.27, pI 6.10, and extinction molar coefficient of 9105 M-1 cm-1. MpBBI inhibits strongly trypsin with K i in the 10-10 M range and was stable in a wide array of pH and extreme temperatures. MpBBI comparative modeling was applied to gain insight into its 3D structure and highlighted some distinguishing features: (1) two non-identical loops, (2) loop 1 (CEEESRC) is completely different from any known BBI, and (3) the amount of disulphide bonds is also different from any reported BBI from dicot plants.


Asunto(s)
Maclura/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Semillas/química , Inhibidores de Tripsina/metabolismo , Clonación Molecular , Modelos Moleculares , Mapeo Peptídico , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Conformación Proteica , Homología de Secuencia de Aminoácido , Tripsina/metabolismo , Inhibidor de la Tripsina de Soja de Bowman-Birk , Inhibidores de Tripsina/química , Inhibidores de Tripsina/aislamiento & purificación
12.
J Microencapsul ; 33(5): 487-496, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27400260

RESUMEN

The regularities of release of therapeutic antioxidant enzyme superoxide dismutase (SOD) from various alginate-based delivery systems (DS) into simulated gastric and intestinal fluids were determined. The following systems were used: Ca-alginate granules (AG) prepared by various methods, porous carbonate cores with multilayer polyelectrolyte coating as well as the new two-level DS (Ca-AG containing carbonate cores loaded with proteins). The influence of the method of granule preparation, composition of gelation bath and ionic composition of the simulated fluids on release profiles of the protein from different DS was revealed. SEM images demonstrated changes in DS structures in various simulated fluids. The correlation between these changes and in vitro protein release was shown. The comparison of enzymatic activity of SOD encapsulated in DS of various configurations (including the systems containing different peptidase inhibitors) was made. The efficiency of protection of SOD activity in simulated intestinal fluid with trypsin was demonstrated.

13.
Fish Shellfish Immunol ; 37(2): 215-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24560682

RESUMEN

Shi drum is a new fish species recently cultivated in Greek fish farms. Its feeding requirements and health status must be determined in order to optimize its culture conditions. The present study looked at the effects of different dietary protein levels (47 or 52%) in combination with 3 lipid levels (10, 15 or 20%) on the immune system of juvenile shi drums. Most immune parameters assessed were affected by the dietary treatment. The ceruloplasmin activity, the whole blood respiratory burst activity, the serum myeloperoxidase activity, the antibacterial activity of serum lysozyme and the serum antiprotease activity all varied with the dietary protein/lipid ratio. In view of these results, the lowest dietary lipid level tested (10%) was optimal for the immune system of shi drum but a clear determination of the optimal dietary protein levels was not obtained as 47% reduced stress but also increased the ceruloplasmin response of the fish. A dietary lipid level of 10% lipids was recommended for optimal immune status of the fish. Dietary protein level of 47% seemed to give better immune responses but further study is needed to refine protein requirements.


Asunto(s)
Dieta/veterinaria , Grasas de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , Inmunidad Innata/inmunología , Perciformes/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Análisis Químico de la Sangre/veterinaria , Relación Dosis-Respuesta a Droga , Explotaciones Pesqueras , Perciformes/inmunología
14.
Clin Chim Acta ; 425: 48-53, 2013 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-23867953

RESUMEN

BACKGROUND: The functions of proteins can be retained following separation by non-denaturing two-dimensional electrophoresis (2-DE). The trypsin inhibition activities can then be examined following the separation and immobilization of the proteins under non-denaturing conditions. METHODS: Human plasma proteins were separated using 2-DE and transferred onto a polyvinylidene difluoride membrane and stained using Ponceau S. The trypsin inhibition activity of the membrane-bound proteins was qualitatively examined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The activities were also quantitatively examined by analyzing the release of the azo-chromophore when azocasein was the substrate. RESULTS: Trypsin activity was inhibited by the haptoglobin and α2-macroglobulin spots located on the membrane, whereas the protease activity was retained for the spots containing albumin and transferrin. The inhibition activities of the α2-macroglobulin and haptoglobin spots were 4.81- and 4.83-fold higher, respectively, when compared with the inhibition activity of the albumin spot. An axis of the relative activities of trypsin inhibition was added to the 2-DE pattern of human plasma proteins to construct a non-denaturing 3-D map of human plasma proteins. CONCLUSION: This 3-D map should represent a suitable diagnostic tool for the qualitative and quantitative analyses of the trypsin inhibition activities of proteins.


Asunto(s)
Electroforesis en Gel Bidimensional , Haptoglobinas/química , Inhibidores de Tripsina/química , Tripsina/química , alfa-Macroglobulinas/química , Compuestos Azo , Caseínas/química , Fraccionamiento Químico , Haptoglobinas/aislamiento & purificación , Humanos , Membranas Artificiales , Mapeo Peptídico , Polivinilos , Albúmina Sérica/química , Albúmina Sérica/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Transferrina/química , Transferrina/aislamiento & purificación , Inhibidores de Tripsina/aislamiento & purificación , alfa-Macroglobulinas/aislamiento & purificación
15.
Ciênc. agrotec., (Impr.) ; 34(2): 361-366, mar.-abr. 2010. ilus
Artículo en Portugués | LILACS | ID: lil-546663

RESUMEN

Inibidores de tripsina representam uma estratégia de controle de insetos e, por isso, a identificação e caracterização desses inibidores são etapas muito importantes para que novas formas de controle de pragas sejam desenvolvidas. Os inibidores de tripsina atuam na digestão primária de proteínas e comprometem o processo digestivo por completo, reduzindo a disponibilidade de aminoácidos ao inseto. A incorporação de inibidores de tripsina na dieta de insetos-praga é uma forma de controle cuja eficácia foi verificada por diferentes autores. Este projeto foi conduzido a fim de se observar a eficiência de extratos de folhas de mamona na inibição "in vitro" de proteinases do tipo tripsina do bicho-mineiro do cafeeiro. Após testes realizados com os extratos de folhas de mamona não-fervidos e fervidos com e sem a adição de β-mercaptoetanol 0,2 por cento (v/v) e mediante precipitações com acetona, verificou-se que o inibidor é uma molécula termoresistente e não-protéica. Desta forma, iniciou-se um processo de purificação da molécula inibidora por meio de cromatografia de adsorção com posterior análise em espectrômetro de massas. Os resultados dos testes de inibição indicaram a presença de um inibidor de tripsina eficaz contra o bicho-mineiro do cafeeiro nos extratos de folhas de mamona capaz de inibir 2,48 + 0,15 UTI, o que representa aproximadamente 40 por cento de inibição. Em testes realizados com tripsina bovina observou-se que o extrato de folhas de mamona não apresenta poder de inibição sobre essa enzima.


Trypsin inhibitors stand for a strategy of insect control and, therefore, the identification and characterization of these inhibitors are very important steps for new forms of pest control to be developed. Trypsin inhibitors act in the primary digestion of proteins and endanger the digestive process wholly, reducing the availability of aminoacids to the insect. The incorporation of trypsin inhibitors in the diet of pest insects is a control form whose efficacy was verified by different authors. In order to observe the efficiency of castor bean leaf extracts in inhibiting trypsin-like enzymes of the coffee leaf miner, an experiment was carried out with the purpose of observing an "in vitro" inhibition phenomenon. The results of the trypsin inhibition tests with normal and boiled with and without β-mercaptoethanol 0.2 percent (v/v) castor bean leaf extracts and the results of the acetone precipitation process indicated that the inhibitor is a heat-resistant molecule and it is not a protein. This way, the purification process was made by adsorption chromatography with later analysis in mass spectrometer. The reached results indicated that the presence of a trypsin inhibitor of the coffee leaf miner in the castor bean leaf extracts is capable of inhibiting 2.48 + 0.15 UTI, which stands for about 40 percent of inhibition. Tests performed with bovine trypsin indicated that the castor bean leaf extract have no inhibiting power on this enzyme.

16.
ACS Med Chem Lett ; 1(9): 499-503, 2010 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-24900238

RESUMEN

Molecular graph theory was used to design a unique and diverse, high-efficiency fragment screening collection. A data set retrieved from the annotated database AurSCOPE GPS was used as the reference set, and the GDB-13 database, a virtual library of enumerated organic molecules, was used as a source for the fragment selection. The data graph collection of Discngine as implemented in PipelinePilot was applied to perform the graph pharmacophore similarity matching between the reference and the GDB-13 data sets, leading to the ultimate fragment screening library. The relevance of this unique fragment collection was demonstrated by means of a virtual screening exercise using human trypsin as a test case. Several novel entities with high similarity to known trypsin inhibitors were identified in the in silico exercise. The application of this unique, high fragment efficiency collection to other protein targets in the framework of fragment-based drug discovery is warranted.

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