Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.32 (bromelain)
 1,025 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adsorption and desorption isotherms of two commercial enzyme preparations of papain and bromelain were determined with a Dynamic Vapor System. The Guggenheim-Anderson-deBoer (GAB) modeling of the obtained sorption isotherms allowed the definition of different levels of hydration of those samples. Afterward, these enzyme preparations were used as biocatalysts in water and solvent-free esterification and alcoholysis reactions. The evolution of the obtained fatty acid ester level as a function of the initial hydration level of the biocatalyst, i.e., thermodynamic water activity (a(w)) and water content, was studied. The results show an important correlation between the initial hydration level of the biocatalyst and its catalytic activity during the lipase-catalyzed synthesis reactions. Thus, the Carica papaya lipase (crude papain preparation) catalytic activity is highly dependent on the biocatalyst hydration state. The optimized synthesis reaction yield is obtained when the a(w) value of the enzyme preparation is stabilized at 0.22, which corresponds to 2% water content. This optimal level of hydration occurs on the linear part of the biocatalyst's sorption isotherm, where the water molecules can form a mono- or multiple layer with the protein network. The synthesis reaction yield decreases when the a(w) of the preparation is higher than 0.22, because the excess water molecules modify the system equilibrium leading to the reverse and competitive reaction, i.e., hydrolysis. These results show also that an optimal storage condition for the highly hydrophilic crude papain preparation is a relative humidity strictly lower than 70% to avoid an irreversible structural transition leading to a useless biocatalyst. Concerning the bromelain preparation, no effect of the hydration level on the catalytic activity during esterification reactions was observed. This biocatalyst has too weak a catalytic activity which makes it difficult to observe any differences. Furthermore, the bromelain preparation is far more hydrophobic as it adsorbs only 18 g of water per 100 g of dry material at a(w) around 0.90. No deliquescence of this enzymatic preparation is observed at this a(w) value.
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PMID:Plant lipases: biocatalyst aqueous environment in relation to optimal catalytic activity in lipase-catalyzed synthesis reactions. 1180 65

Ileus continues to be a common consequence of abdominal surgery, causing significant patient discomfort and often leading to more serious problems. The therapy available is limited, hence, ileus remains an important clinical problem. Activation of inducible nitric oxide synthase (iNOS) directly modulates intestinal dysmotility after bowel manipulation and plays an essential role in initiating intestinal inflammation. Nuclear factor (NF)-kappaB is known to be a critical component of iNOS gene transcriptional activation in response to inflammatory stimuli. Bromelain is a crude extract from the pineapple stem, which is sold as a nutritional supplement to "promote digestive health" and as an anti-inflammatory medication in some developed countries. Here, we have found that oral administration of bromelain improves decrease in defecation in abdominal postoperative rats. Results showed that bromelain increased the wet weight, dry weight, water content and number of fecal pellets in laparotomized plus mechanically manipulated rats, suggesting improvement of postoperative ileus. Furthermore, bromelain treatment inhibited overexpressed iNOS mRNA and restored down-regulated inhibitor kappaBalpha mRNA in the colon of the postoperative rats. From the in vitro experiments, bromelain inhibits lipopolysaccharide (LPS)-induced nitrite overproduction in macrophage cell lines and LPS-induced NF-kappaB luciferase reporter gene expression in RAW264.7 macrophages transfected with NF-kappaB luciferase reporter gene. Thus, our findings suggest that bromelain improves decrease in defecation in postoperative rats, at least in part, by inhibiting colonic iNOS overexpression via NF-kappaB pathway. Our data indicates that bromelain may benefit patients with postoperative ileus.
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PMID:Bromelain improves decrease in defecation in postoperative rats: modulation of colonic gene expression of inducible nitric oxide synthase. 1613 11

Previous work demonstrated that a commercial formulation of piperonyl butoxide (PBO) did inhibit the activity of some plant proteolytic enzymes. In this paper, the effect of pure PBO and nine pure PBO homologues (PBOH) appropriately synthesized toward bromelain and papain was studied in hydrocarbon solution using the bis(2-ethylhexyl)sodium sulfosuccinate (AOT) reverse micellar system. This study establishes that the majority of these compounds show, in vitro, interesting protease inhibition activities. The benzodioxole and dihydrobenzofuran structures, in particular, 5-[2-(2-butoxyethoxy)ethoxymethyl]-benzo[1,3]dioxole (EN 1-40) and 6-[2-(2-butoxyethoxy)ethoxymethyl]-5-propyl-2,3-dihydrobenzofuran (EN 16-5), respectively, appear to be responsible for protease inhibition. Measures of octanol/water partition coefficients on PBO and PBOH have demonstrated that water solubility plays a fundamental role in the expression of protease inhibition activity.
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PMID:Benzodioxole derivatives as negative effectors of plant proteases. 1615 78

This paper described a novel assay of enzyme based on the measurement of enhanced resonance light-scattering (RLS) signals resulting from the electrostatic and coordination interaction of functionalized CdTe nanoparticles with enzyme. The CdTe nanoparticles which were modified with 3-mercaptocarboxylic acid (MPA) have abundant carboxylic groups (COOH). So the nanoparticles are water-soluble, stable and biocompatible. At pH 8.3 phosphate buffered saline (PBS), the RLS signals of functionalized nano-CdTe are greatly enhanced by bromelain and papain in the region of 220-800 nm characterized by the peak around 318-314 nm, respectively. The optimization conditions of the reaction were also examined and selected. Under the selected conditions, the enhanced RLS intensity is linearly proportional to the concentration of bromelain and papain. The liner range is (0.09-0.9) x 10(-6)mol/L for bromelain and (0.048-0.702) x 10(-6)mol/L for papain. The influences of some foreign substances were also examined. This method can be applied to the determination of enzyme.
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PMID:Resonance light-scattering spectrometric study of interaction between enzyme and MPA-modified CdTe nanoparticles. 1785 Nov 21

The main purpose of this research was to investigate the antitumor and antimicrobial activities of the chitooligosaccharides containing hydrolyzates obtained from the hydrolysis of chitinous materials (such as chitin, chitosan, and squid pen) by bromelain. The optimum preparations were gained in the hydrolysates of squid pen powder hydrolyzed at pH 5, 37 degrees C for 2 days by 0.1% bromelain. The hydrolysates had an 80% inhibitory activity on phyto-pathogenic mold Fusarium oxysporum. Chitooligosaccharides were recovered from the hydrolysates and were used for tumor cell surviving test. Surviving rate of the human leukemic U937 cells was reduced to 69% by the chitooligosaccharides. The solution of 0.1% of water-soluble chitosan was also hydrolyzed for 1 day at pH 5, 37 degrees C by bromelain. The resultant hydrolysates contained the highest chitooligosaccharides, which had inhibitory effect on Bacillus subtilis and also had 40% inhibitory activity on human pathogenic mold Aspergillus fumigatus. Surviving rate of mouse CT26 colorectal adenocarcinoma cells was reduced to 57% by the chitooligosaccharides. This is the first publication of enzymatic reclamation of squid pen (fishery processing waste) for the preparation of antitumor and antimicrobial materials.
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PMID:Reclamation of chitinous materials by bromelain for the preparation of antitumor and antifungal materials. 1792 Feb 62

Rice bran protein was extracted by using defatted rice bran and water at 1:6 (w/w) and 6% of bromelain at pH 9.0, 50 degrees C, 500 rpm for 15 and 30 mins. The degree of hydrolysis (DH) of rice bran protein extract (RBPE) was 19 and 36.5%, respectively, and their nitrogen solubility was higher than the controls. Rice bran protein concentrate (RBPC) was prepared by spray drying. Emulsion activity of RBPC produced from 19% DH RBPE was increased while emulsion stability index was not significantly different from the control. Foam capacity and rehydration ability of RBPC were greater than the control.
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PMID:Preparation and some functional properties of rice bran protein concentrate at different degree of hydrolysis using bromelain and alkaline extraction. 1929 80

Deep burns are associated with the formation of an eschar, which delays healing and increases the risk of infection. Surgical debridement of the eschar is, at present, the fastest means to achieve an eschar-free bed, but the process can not differentiate between the viable tissue and the eschar and follow the minute irregularities of the interface between the two. We evaluated the efficacy and selectivity of a novel enzymatic bromelain-based debriding agent, Debrase Gel Dressing (Debrase), in a porcine comb burn model. We hypothesized that Debrase would result in rapid debridement of the eschar without adverse effects on the surrounding uninjured skin. This is a prospective, controlled, animal experiment. Five domestic pigs (20-25 kg) were used in this study. Sixteen burns were created on each animal's dorsum using a brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds, resulting in four rectangular 10 x 20 mm full-thickness burns and separated by three 5 x 20 mm unburned interspaces representing the zone of stasis. The burned keratin layer (blisters) was removed, and the burns were treated with a single, topical, Debrase or control vehicle application for 4 hours. The Debrase/control was then wiped off using a metal forceps handle, and the burns were treated with a topical silver sulfadiazine (SSD). The wounds were observed, and full-thickness biopsies were obtained at 4 and 48 hours for evidence of dermal thickness, vascular thrombosis, and burn depth, both within the comb burns and the unburned interspaces in between them. Chi-square and t tests are used for data analysis. A single 4-hour topical application of Debrase resulted in rapid and complete eschar dissolution of all the burns in which the keratin layer was removed. The remaining dermis was thinner (1.1 +/- 0.7 mm) than in the control burns (2.1 +/- 0.3 mm; difference 0.9 mm [95% confidence interval: 0.3-1.4]) and was viable with no injury to the normal surrounding skin or to the unburned interspaces between the burns, which represents the zone of stasis. In control burns, the entire thickness of the dermis was necrotic. At 48 hours, Debrase-treated areas were found partially desiccated under SSD treatment. The unburned interspaces demonstrated partial-thickness necrosis in two third and full-thickness necrosis in one third of wounds. In contrast, full-thickness necrosis was noted in all control interspaces (P = .05). In a porcine comb burn model, a single, 4-hour topical application of Debrase resulted in rapid removal of the necrotic layer of the dermis with preservation of unburned tissues. At 48 hours, SSD treatment resulted in superficial tissue damage and partial preservation of the unburned interspaces.
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PMID:Rapid and selective enzymatic debridement of porcine comb burns with bromelain-derived Debrase: acute-phase preservation of noninjured tissue and zone of stasis. 2018 76

Exogenous enzymes tenderize meat through proteolysis. Triceps brachii and Supraspinatus were randomly assigned to the seven enzyme treatments, papain, ficin, bromelain, homogenized fresh ginger, Bacillus subtilis protease, and two Aspergillus oryzae proteases or control to determine the extent of tenderization (Warner-Bratzler shear and sensory evaluation) and mode of action (myofibrillar or collagen degradation). Sensory evaluation showed improvement (P<0.0009) for tenderness and connective tissue component and all except ginger had a lower shear force than the control (P<0.003). Ginger produced more off-flavor than all other treatments (P<0.0001). Only papain increased soluble collagen (P<0.0001). Control samples were only significantly less than ficin for water soluble (P=0.0002) and A. oryzae concentrate for salt soluble proteins (P=0.0148). All enzyme treatments can increase tenderness via myofibrillar and collagenous protein degradation with no difference among high and low-connective tissue muscles.
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PMID:Application of exogenous enzymes to beef muscle of high and low-connective tissue. 2041 88

Reepithelialization of deep burns requires spontaneous or active removal or debridement of the necrotic eschar, as recently defined by the American Burn Association. Debrase is a bromelain-derived enzymatic preparation that has been shown to result in rapid and selective debridement of human and animal burns. The authors hypothesized that rapid debridement of deep dermal burns with Debrase would result in earlier reepithelialization of the remaining dermis in a porcine model. Eighty deep dermal contact burns measuring 10 by 20 mm were created on the back and flanks of anesthetized domestic pigs (25 kg) using a brass template preheated in boiling water (100 degrees C) that was applied to the skin for a period of 30 seconds. The template was applied using a spring-loaded device designed to control the amount of pressure applied to the skin by the template. Burns were randomized to a 4-hour topical application of Debrase (lyophilized dry enzyme dissolved and activated in a hydrating vehicle) (n = 40) or its hydrating vehicle (n = 40) followed by daily application of a petrolatum-based antibiotic ointment. Wounds were visually assessed and photographed daily. Four-millimeter full-thickness punch biopsies were obtained for histological analysis using hematoxylin and eosin staining by a board-certified dermatopathologist masked to burn therapy at 7, 11, 13, and 15 days after injury. The primary outcome was the percentage of the burns that were completely reepithelialized at each time point. Secondary outcomes were time to complete reepithelialization and the mean percentage of reepithelialization on microscopic analysis. A sample of 40 burns in each group had 80% power to detect a 20% difference in the percentage of completely reepithelialized burns (two tailed, P < .05). The percentage of completely reepithelialized burns was higher for Debrase than control burns at days 11 (40.9% vs 3.1%; P = .002), 13 (87.5% vs 50%; P = .007), and 15 (97.5% vs 77.5%, P = .018). The mean (SD) percentage reepithelialization of Debrase-treated burns at 7 days was higher than of control burns (47.6% [3.2] vs 0% [0]; P < .001). A larger number of cells in the epidermis and dermis of debrided burns stained positive for the proliferation antigen Ki-67. There was no evidence of any adverse events in the normal skin adjacent to the Debrase-treated burns. Rapid enzymatic debridement of deep partial-thickness burns with Debrase results in earlier reepithelialization and cellular proliferation in swine, when compared with carrier and topical antibiotic dressings alone.
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PMID:The effects of rapid enzymatic debridement of deep partial-thickness burns with Debrase on wound reepithelialization in swine. 2066 Nov 48

Enzymatic synthesis of oligopeptides from l-phenylalanine ethyl ester hydrochloride (l-Phe-Et.HCl) and other l-form hydrophobic amino acid ester hydrochlorides in water miscible organic cosolvents was studied. Different proteases, water miscible cosolvents, and effect of different ratios of water miscible cosolvents for protease-catalyzed oligo-phenylalanine [oligo(l-Phe)] were compared. The importance of the use of water miscible cosolvents in transforming reactions from heterogeneous to homogeneous conditions as a potent medium engineering tool for protease-catalyzed oligopeptide synthesis is highlighted. For example, at 0.125 M l-Phe-Et.HCl, 20% (v/v) methanol, 18.6 mg/mL bromelain, in phosphate buffer (0.25M, pH 8), 40 degrees C, for 3 h, oligo(l-Phe) precipitated from the solution to yield 45 +/- 5%, in contrast, in the absence of cosolvent oligo(l-Phe) yield of 29 +/- 5% was obtained. The following reaction conditions were optimized for bromelain catalyzed oligo(l-Phe) synthesis: pH, temperature, substrate, enzyme, and cosolvent concentrations. DP(avg) and chain length distribution in the product peptides were investigated by (1)H NMR and MALDI-TOF.
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PMID:Protease-catalyzed oligomerization of hydrophobic amino acid ethyl esters in homogeneous reaction media using l-phenylalanine as a model system. 2069 Jul 22


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