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Bromelain, papain, and ficin are studied the most for meat tenderization, but have limited application due to their short lifetime. The aim of this work is to identify the adsorption mechanisms of these cysteine proteases on chito...
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Bromelain, papain, and ficin are studied the most for meat tenderization, but have limited application due to their short lifetime. The aim of this work is to identify the adsorption mechanisms of these cysteine proteases on chitosan to improve the enzymes' stability. It is known that immobilization can lead to a significant loss of enzyme activity, which we observed during the sorption of bromelain (protease activity compared to soluble enzyme is 49% for medium and 64% for high molecular weight chitosan), papain (34 and 28% respectively) and ficin (69 and 70% respectively). Immobilization on the chitosan matrix leads to a partial destruction of protein helical structure (from 5 to 19%). Using computer modelling, we have shown that the sorption of cysteine proteases on chitosan is carried out by molecule regions located on the border of domains L and R, including active cites of the enzymes, which explains the decrease in their catalytic activity upon immobilization. The immobilization on chitosan does not shift the optimal range of pH (7.5) and temperature values (60 degrees C for bromelain and papain, 37 & ndash;60 degrees C for ficin), but significantly increases the stability of biocatalysts (from 5.8 times for bromelain to 7.6 times for papain).
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The fig's ficin is a cysteine endoproteolytic enzyme, which plays fundamental roles in many plant physiological processes, and has many applications in different industries such as pharmaceutical and food. In this work, we report ...
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The fig's ficin is a cysteine endoproteolytic enzyme, which plays fundamental roles in many plant physiological processes, and has many applications in different industries such as pharmaceutical and food. In this work, we report the inhibition and activation of autolysis and structural changes associated with reaction of ficin with iodoacetamide and tetrathionate using high-performance liquid chromatography (HPLC), ultra filtration membrane, and dynamic light scattering (DLS) methods. The ficin structural changes were also determined using UV-absorption, circular dichroism (CD), fluorescence spectroscopy, and differential scanning calorimetry (DSC) techniques. These techniques demonstrated that iodoacetamide completely inhibited ficin autolysis, which was irreversible. However, tetrathionate partially and reversibility inhibited its autolysis. The ficin structural changes with two synthetic inhibitors were associated with secondary structural changes related to decreased alpha-helix and increased beta sheet and random coil conformations, contributing to its aggregation. (C) 2015 Elsevier B.V. All rights reserved.
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The content and enzymatic activity of ficin in leaves of fig cultivars grown in Absheron were studied at various stages of development. The effects of EDTA and mercaptoethanol on its activity was studied. The best sources of ficin...
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The content and enzymatic activity of ficin in leaves of fig cultivars grown in Absheron were studied at various stages of development. The effects of EDTA and mercaptoethanol on its activity was studied. The best sources of ficin are leaves taken from the cultivar Buzovburnu in the first period of fruiting (June-July) and Sary Apsheron in the second period (July-August).
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This study investigates the features of interactions between cysteine proteases (bromelain, ficin, and papain) and a graft copolymer of carboxymethyl cellulose sodium salt with N-vinylimidazole. The objective is to understand the ...
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This study investigates the features of interactions between cysteine proteases (bromelain, ficin, and papain) and a graft copolymer of carboxymethyl cellulose sodium salt with N-vinylimidazole. The objective is to understand the influence of this interactions on the proteolytic activity and stability of the enzymes. The enzymes were immobilized through complexation with the carrier. The interaction mechanism was examined using Fourier-transform infrared spectroscopy and flexible molecular docking simulations. The findings reveal that the enzymes interact with the functional groups of the carrier via amino acid residues, resulting in the formation of secondary structure elements and enzyme's active sites. These interactions induce modulation of active site of the enzymes, leading to an enhancement in their proteolytic activity. Furthermore, the immobilized enzymes demonstrate superior stability compared to their native counterparts. Notably, during a 21-day incubation period, no protein release from the conjugates was observed. These results suggest that the complexation of the enzymes with the graft copolymer has the potential to improve their performance as biocatalysts, with applications in various fields such as biomedicine, pharmaceutics, and biotechnology.
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? 2022 Elsevier LtdEnzymatic whey proteins concentrates (WPC) hydrolysis under optimal conditions of ficin crude extract (FCE) in two ratios E/S (0.5 and 1%) was studied, assessing the impact of hydrolysis on WPC by determination ...
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? 2022 Elsevier LtdEnzymatic whey proteins concentrates (WPC) hydrolysis under optimal conditions of ficin crude extract (FCE) in two ratios E/S (0.5 and 1%) was studied, assessing the impact of hydrolysis on WPC by determination degree of hydrolysis (DH), Fast proteins liquid chromatography (FPLC), Tricine SDS-PAGE, antioxidant activity at sampling time beside, and technological properties (solubility, emulsifying activity index (EAI) and foaming activity (FA)) at the best condition (maximum DH and antioxidant activity) other side. Results showed, in the first 30 min, DH reached 22.76% at E/S (1%) with a total degradation of α-lactalbumin (α-La) and almost of β-lactoglobulin (β-Lg). A significant increase in antioxidant activity and solubility was observed, while not for EAI, and FA. These results indicate for the first time that β-Lg is susceptible to hydrolyse by FCE that rarely found for other enzymes. Ficin hydrolysates showed very relevant performance, and suggest that could be appropriate production of functional ingredients.
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In this work, ficin extract (3.4.22.3, >1.0 u/mg) was immobilized for the first time in poly (vinyl alcohol) (PVA) electrospun nanofibers in order to preserve its tridimensional molecular structure. The analysis of the morphology ...
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In this work, ficin extract (3.4.22.3, >1.0 u/mg) was immobilized for the first time in poly (vinyl alcohol) (PVA) electrospun nanofibers in order to preserve its tridimensional molecular structure. The analysis of the morphology of the electrospun nanofibers was carried out using scanning electron microscopy (SEM) showing a diameter in the range of 124-194 nm. The interaction of the ficin extract with the nanofibers structure was analyzed by infrared spectroscopy (FTIR) analysis. The immobilization step was achieved through crosslinking involving the exposure to glutaraldehyde (GA) vapor. The enzyme catalytic behavior was followed by ultraviolet spectroscopy (UV) using the Earlanger method using N-alpha-benzoyl-L-arginine-4-nitroanilide hydrochloride (BAPA) as substrate. The maximum catalytic activity was reached with 1 h of crosslinking, 20% of enzyme loading and pH 8. The immobilized ficin extract showed 92% of the enzyme activity of the crude ficin extract. The enzymatic activity of the immobilized ficin extract was conserved after a total of nine reuse cycles and maintained after being stored for 25 days. Finally, both the glass transition (T-g) and heat of fusion (H-f) were affected by number of enzyme molecules inside the polymeric nanofibers matrix according to the study of the thermal properties by differential scanning calorimetry (DSC). 2018 Elsevier B.V. All rights reserved.
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The peroxidase-like activity of ficin is relatively low, which limits its application. It was found that thiol groups of ficin could inhibit its peroxidase-like activity. So, two procedures, i.e., direct blocking with N-ethylmalei...
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The peroxidase-like activity of ficin is relatively low, which limits its application. It was found that thiol groups of ficin could inhibit its peroxidase-like activity. So, two procedures, i.e., direct blocking with N-ethylmaleimide (NEM), or using tris (2-carboxyethyl) phosphine hydrochloride (TCEP) to interrupt disulfide bonds then blocking thiol groups with NEM, were applied to block thiol groups of ficin, ficin-NEM (ficin-N) and ficin-TCEP-NEM (ficin-TN) were produced, respectively. The blocking of thiol groups accelerated the peroxidase activity dramatically. The peroxidase catalytic activity of ficin-N and ficin-TN toward the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) oxidation by H2O2 was about 2.5-fold and 5-fold increase compared with ficin, respectively, which accompanied a color change from colorless to blue and followed classic Michaelis-Menten model. The kinetic parameters indicated that higher affinity of ficin-N (K-m = 0.31) and ficin-TN (K-m = 0.39) to H2O2 compared with ficin (K-m = 0.58), and ficin-TN had the highest K-cat which increased by 6.5 times and 4.5 times for TMB and H2O2, respectively. According to these findings, a colorimetric method with high sensitivity for the detection of biothiols was developed due to sulfhydryl compounds inhibited the peroxidase activity of ficin. Comparing with ficin and ficin-N, ficin-TN had the widest detection range (0.01-16 mu M) and the lowest detection limit (3 nM). The practical applications of ficin-TN for biothiol determination in human serum samples have been demonstrated with satisfactory results. Ficin-N and ficin-TN are promising to apply to the bioanalysis.
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The latex of the common fig (Ficus carica) contains a mixture of at least five cysteine proteases commonly known as ficins (EC 3.4.22.3). Four of these proteases were purified to homogeneity and crystals were obtained in a variety...
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The latex of the common fig (Ficus carica) contains a mixture of at least five cysteine proteases commonly known as ficins (EC 3.4.22.3). Four of these proteases were purified to homogeneity and crystals were obtained in a variety of conditions. The four ficin (iso)forms appear in ten different crystal forms. All diffracted to better than 2.10 angstrom resolution and for each form at least one crystal form diffracted to 1.60 angstrom resolution or higher. Ficin (iso) forms B and C share a common crystal form, suggesting close sequence and structural similarity. The latter diffracted to a resolution of 1.20 angstrom and belonged to space group P3(1)21 or P3(2)21, with unit-cell parameters a = b = 88.9, c = 55.9 angstrom.
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A Surface Plasmon Resonance Imaging (SPRI) sensor based on bromelain or chymopapain or ficin has been developed for specific cystatin determination. Cystatin was captured from a solution by immobilized bromelain or chymopapain or ...
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A Surface Plasmon Resonance Imaging (SPRI) sensor based on bromelain or chymopapain or ficin has been developed for specific cystatin determination. Cystatin was captured from a solution by immobilized bromelain or chymopapain or ficin due to the formation of an enzyme-inhibitor complex on the biosensor surface. The influence of bromelain, chymopapain or ficin concentration, as well as the pH of the interaction on the SPRI signal, was investigated and optimized. Sensor dynamic response range is between 0-0.6 mg/ml and the detection limit is equal to 0.1 mg/ml. In order to demonstrate the sensor potential, cystatin was determined in blood plasma, urine and saliva, showing good agreement with the data reported in the literature.
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Ficin is actively used in the food industry like as brewing, baking, in the manufacture of meat and fish products, has potential properties for effective use in medicine and pharmacology, so a deeper study of the structure of the ...
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Ficin is actively used in the food industry like as brewing, baking, in the manufacture of meat and fish products, has potential properties for effective use in medicine and pharmacology, so a deeper study of the structure of the enzyme molecule is needed. Knowledge of the spatial structure of the enzyme makes it possible to understand and predict the behavior of the biocatalyst in various technological processes. Reconstruction of the spatial structure of the plant protease ficin (EC 3.4.22.3) from Pisum sativum (GenBank: AAB41816.1) was performed using high-performance computer modeling. The molecular structure of papain from Carica papaya (PDB ID: 9PAP) was used as a model for a similar homologous protein from which the reconstruction was carried out. The reconstructed enzyme model was compared with the deposited ficin structure (PDB ID: 4YYU). The search for ficin homologs (EC 3.4.22.3) from Pisum sativum (GenBank: AAB41816.1) was performed using the FASTA and PSI-BLAST servers in the PDB protein structure database. Multiple alignment was performed using the CLUSTALW server. Alignment calculations and visualization were performed using the UGENE 1.25 bioinformatics package. After processing the initial data, the resulting structure was optimized and relaxed in the AMBER96 force field for 100 picoseconds. The protocol of the method for obtaining a model is given in detail, which can be used both for scientific and educational purposes.
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