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1.
Bioprocess Biosyst Eng ; 40(9): 1391-1398, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28624929

RESUMEN

Dehairing of crude leather is a critical stage performed at the beginning of its processing to obtain industrially useful pieces. Tanneries traditionally apply a chemical process based on sodium sulfide. Since this chemical reactive is environmentally toxic and inefficiently recycled, innovative protocols for reducing or eliminating its use in leather depilation are welcomed. Therefore, latex peptidases from Calotropis procera (CpLP) and Cryptostegia grandiflora (CgLP) were assayed for this purpose. Enzyme activity on substrates representative of skin such as hide powder azure (UHPA), elastin (UE), azocollagen (UAZOCOL), keratin (UK), and epidermis (UEP) was determined, while depilation activity was assayed on cow hide. Only CpLP was active against keratin (13.4 UK) and only CgLP was active against elastin (0.12 UE). CpLP (93.0 UHPA, 403.6 UAZOCOL, 36.3 UEP) showed higher activity against the other substrates than CgLP (47.6 UHPA, 261.5 UAZOCOL, 8.5 UEP). In pilot assays, CpLP (0.05% w/v with sodium sulfite 0.6% w/v as activator) released hairs from cow hide pieces. Macroscopic and microscopic analyses of the hide revealed that the dehairing process was complete and the leather structure was preserved. The proteolytic system of C. procera is a suitable bioresources to be exploited by tanneries.


Asunto(s)
Calotropis/enzimología , Látex , Péptido Hidrolasas/química , Proteínas de Plantas/química , Piel/química , Especificidad por Sustrato
2.
Blood Coagul Fibrinolysis ; 27(4): 441-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26886361

RESUMEN

Extracts rich in cysteine proteases obtained from fruits of Pseudananas macrodontes (Pm), Bromelia balansae (Bb), and B. hieronymi (Bh) have previously shown an anti-inflammatory effect on animal models. Given the close relationship between hemostasis and inflammation, it is attractive to investigate therapeutic agents capable of modulating both systems. The aim of this work was to study the effect of Pm, Bb, and Bh on fibrin(ogen) and blood coagulation compared with stem bromelain (Bro). Action on fibrinogen was electrophoretically and spectrophotometrically evaluated, fibrinolytic activity was measured both electrophoretically and by the fibrin plate assay, and the effect on blood coagulation was studied by conventional coagulation tests (PT and APPT). All extracts showed the same proteolytic preference for fibrinogen subunits, that is Aα > Bß, whereas γ was partially hydrolyzed by 100-fold concentration increase. Unlike Bro, cysteine proteases of Pm, Bb, and Bh increased absorbance at 540 nm of fibrinogen solution, suggesting thrombin-like activity, which was time-dependent and reached maximum values at lower concentration. All extracts showed the same proteolytic preference for fibrin subunits; however Pm, Bb, and Bh showed lower fibrinolytic activity than Bro at the assayed concentrations. Although Bb acted only as anticoagulant, Pm, Bh, and unexpectedly Bro showed dual action on blood coagulation: at low concentration showed procoagulant effect and at high concentration anticoagulant effect. Results reveal new plant species as potential sources of pharmacological agents for the treatment of a wide range of hemostatic disorders as well as to wound healing.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Bromelia/química , Bromeliaceae/química , Fibrina/química , Fibrinógeno/química , Fibrinolíticos/farmacología , Frutas/química , Células Sanguíneas/efectos de los fármacos , Pruebas de Coagulación Sanguínea , Bromelaínas/química , Electroforesis en Gel de Poliacrilamida , Productos de Degradación de Fibrina-Fibrinógeno/química , Fibrinolíticos/química , Fibrinolíticos/aislamiento & purificación , Hormesis , Humanos , Extractos Vegetales/química , Cultivo Primario de Células , Proteolisis
3.
Blood Coagul Fibrinolysis ; 24(4): 386-92, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23314383

RESUMEN

Latex proteins have drawn attention because they have shown several pharmacological activities. Herein, the fibrin(ogen)olytic activity of Cryptostegia grandiflora (CgLP) and Plumeria rubra (PrLP) latices were evaluated and characterized. Ion-exchange chromatography separated CgLP in proteolytic (CgLP PI) and nonproteolytic proteins (CgLP PII). CgLP and CgLP PI hydrolyzed azocasein in a dose-dependent manner, whereas CgLP PII and PrLP showed negligible activities. CgLP and CgLP PI accelerated plasmatic clot formation and digested all fibrinogen chains in a time/dose-dependent manner, though in a nonspecific way. CgLP and CgLP PI did not fully hydrolyze the subunits of the fibrin clot since fibrin α-chain showed resistance to proteolysis. No fibrinogenolytic activity was noticed after incubation of CgLP and CgLP PI with E-64. These results suggested that fibrinogenolytic and procoagulant activities of C. grandiflora were performed by cysteine proteases and confirm the activity of latex cysteine proteases as thrombin and plasmin-like proteins.


Asunto(s)
Apocynaceae/química , Fibrinógeno/química , Látex/química , Proteínas de Plantas/química , Electroforesis en Gel de Poliacrilamida , Fibrinolisina/química , Fibrinolisina/aislamiento & purificación , Fibrinólisis , Humanos , Proteínas de Plantas/aislamiento & purificación , Plasma , Polimerizacion , Proteolisis , Trombina/química , Trombina/aislamiento & purificación
4.
Naunyn Schmiedebergs Arch Pharmacol ; 385(5): 455-63, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22315016

RESUMEN

The proteins derived from the latex (LP) of Calotropis procera are well known for their anti-inflammatory property. In view of their protective effect reported in the sepsis model, they were evaluated for their efficacy in maintaining coagulation homeostasis in sepsis. Intraperitoneal injection of LP markedly reduced the procoagulation and thrombocytopenia observed in mice infected with Salmonella; while in normal mice, LP produced a procoagulant effect. In order to understand its mechanism of action, the LP was subjected to ion-exchange chromatography, and the three subfractions (LPPI, LPPII, and LPPIII) thus obtained were tested for their proteolytic effect and thrombin- and plasmin-like activities in vitro. Of the three subfractions tested, LPPII and LPPIII exhibited proteolytic effect on azocasein and exhibited procoagulant effect on human plasma in a concentration-dependent manner. Like trypsin and plasmin, these subfractions produced both fibrinogenolytic and fibrinolytic effects that were mediated through the hydrolysis of the Aα, Bß, and γ chains of fibrinogen and α-polymer and γ-dimer of fibrin clot, respectively. This study shows that the cysteine proteases present in the latex of C. procera exhibit thrombin- and plasmin-like activities and suggests that these proteins have therapeutic potential in various conditions associated with coagulation abnormalities.


Asunto(s)
Calotropis , Proteasas de Cisteína/farmacología , Proteínas de Plantas/farmacología , Infecciones por Salmonella/sangre , Sepsis/sangre , Animales , Coagulación Sanguínea/efectos de los fármacos , Proteasas de Cisteína/aislamiento & purificación , Fibrinógeno/metabolismo , Hemostasis/efectos de los fármacos , Humanos , Látex/química , Masculino , Ratones , Tiempo de Tromboplastina Parcial , Proteínas de Plantas/aislamiento & purificación , Recuento de Plaquetas , Tiempo de Protrombina , Salmonella typhimurium
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