Displaying publications 61 - 80 of 223 in total

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  1. Actions of three clostridial IgA proteases on distinct forms of immunoglobulin A molecules
    Hashim OH, Hassan H
    Immunology, 1991 Jun;73(2):235-8.
    PMID: 2071167
    Three bacterial species of Clostridium (septicum, tertium and sporogenes) were identified to produce extracellular proteases cleaving IgA to Fab and Fc fragments, as demonstrated by SDS-PAGE and immunoelectrophoretic procedures. These enzymes acted on monometric IgA1 paraproteins and normal serum IgA1 but had no activity on IgA2 paraproteins and intact secretory IgA1 from human colostrum. Their action on polyclonal serum IgA1 suggested the absence of neutralizing anti-clostridial IgA protease activity. Although the enzymes were shown not to act on secretory IgA1, they were, however, able to digest free alpha-heavy chains of the dimeric IgA molecules. Susceptibility of the alpha-heavy chain to the proteases was more likely due to the change to a more accessible conformation than because of the absence of neutralizing anti-enzymic activity.
    Matched MeSH terms: Peptide Hydrolases/metabolism; Peptide Hydrolases/physiology*
  2. A comparative study of the biological properties of Australian elapid venoms
    Tan NH, Ponnudurai G
    Comp Biochem Physiol C Comp Pharmacol Toxicol, 1990;97(1):99-106.
    PMID: 1981349
    1. The hemorrhagic, procoagulant, anticoagulant, protease, phosphodiesterase, alkaline phosphomonoesterase, L-amino acid oxidase, acetylcholinesterase, arginine ester hydrolase, phospholipase A, 5'-nucleotidase and hyaluronidase activities of 39 samples of venoms from 13 species (15 taxa) of Australian elapids were determined and the Sephadex G-75 gel filtration patterns for some of the venoms were also examined. 2. The results indicate that Australian elapid venoms can be divided into two groups: procoagulant Australian venoms (including N. scutatus, N. ater, O. scutellatus, O. microlepidotus, P. porphyriacus, T. carinatus, H. stephensii and P. textilis) and non-procoagulant Australian venoms (including A. superbus, P. colletti, P. australis, P. guttatus and A. antarcticus). 3. The non-procoagulant Australian venoms exhibited biological properties similar to other elapid venoms, while the procoagulant Australian venoms exhibited some properties characteristic of viperid venoms. 4. The data show that information on venom biological properties can be used for differentiation of many species of Australian elapids. 5. Particularly useful for this purpose are the hyaluronidase, alkaline phosphomonoesterase, acetylcholinesterase, and the procoagulant activities and the Sephadex G-75 gel filtration patterns of the venoms.
    Matched MeSH terms: Hydrolases/isolation & purification; Hydrolases/metabolism
  3. Simultaneous lactic acidification and coagulation by using recombinant Lactococcus lactis strain
    Raftari M, Ghafourian S, Abu Bakar F
    J Appl Microbiol, 2017 Apr;122(4):1009-1019.
    PMID: 28028882 DOI: 10.1111/jam.13388
    AIMS: This study was an attempt to create a novel milk clotting procedure using a recombinant bacterium capable of milk coagulation.

    METHODS AND RESULTS: The Rhizomucor pusillus proteinase (RPP) gene was sub-cloned into a pALF expression vector. The recombinant pALF-RPP vector was then electro-transferred into Lactococcus lactis. Finally, the milk coagulation ability of recombinant L. lactis carrying a RPP gene was evaluated. Nucleotide sequencing of DNA insertion from the clone revealed that the RPP activity corresponded to an open reading frame consisting of 1218 bp coding for a 43·45 kDa RPP protein. The RPP protein assay results indicated that the highest RPP enzyme expression with 870 Soxhlet units (SU) per ml and 7914 SU/OD were obtained for cultures which were incubated at pH 5·5 and 30°C. Interestingly, milk coagulation was observed after 205 min of inoculating milk with recombinant L. lactis carrying the RPP gene.

    CONCLUSION: The recombinant L. lactis carrying RPP gene has the ability to function as a starter culture for acidifying and subsequently coagulating milk by producing RPP as a milk coagulant agent.

    SIGNIFICANCE AND IMPACT OF THE STUDY: Creating a recombinant starter culture bacterium that is able to coagulate milk. It is significant because the recombinant L. lactis has the ability to work as a starter culture and milk coagulation agent.

    Matched MeSH terms: Peptide Hydrolases/genetics*; Peptide Hydrolases/metabolism
  4. Docking of noncompetitive inhibitors into dengue virus type 2 protease: understanding the interactions with allosteric binding sites
    Othman R, Kiat TS, Khalid N, Yusof R, Newhouse EI, Newhouse JS, et al.
    J Chem Inf Model, 2008 Aug;48(8):1582-91.
    PMID: 18656912 DOI: 10.1021/ci700388k
    A group of flavanones and their chalcones, isolated from Boesenbergia rotunda L., were previously reported to show varying degrees of noncompetitive inhibitory activities toward Dengue virus type 2 (Den2) protease. Results obtained from automated docking studies are in agreement with experimental data in which the ligands were shown to bind to sites other than the active site of the protease. The calculated K(i) values are very small, indicating that the ligands bind quite well to the allosteric binding site. Greater inhibition by pinostrobin, compared to the other compounds, can be explained by H-bonding interaction with the backbone carbonyl of Lys74, which is bonded to Asp75 (one of the catalytic triad residues). In addition, structure-activity relationship analysis yields structural information that may be useful for designing more effective therapeutic drugs against dengue virus infections.
    Matched MeSH terms: Peptide Hydrolases/metabolism*; Peptide Hydrolases/chemistry*
  5. Draft genome sequence of Vitellibacter vladivostokensis KMM 3516(T): a protease-producing bacterium
    Thevarajoo S, Selvaratnam C, Chan KG, Goh KM, Chong CS
    Mar Genomics, 2015 Oct;23:49-50.
    PMID: 25957696 DOI: 10.1016/j.margen.2015.04.009
    Type strain Vitellibacter vladivostokensis KMM 3516(T) (=NBRC 16718(T)) belongs to the phylum Cytophaga-Flavobacterium-Bacteroides. To date, no genomes of the Vitellibacter spp. have been reported, and their metabolic pathways are unknown. This study reports the draft genome sequence of V. vladivostokensis. Moreover, mining of genes associated with proteolytic enzymes was performed to provide insights for further enzyme characterization.
    Matched MeSH terms: Peptide Hydrolases/genetics; Peptide Hydrolases/metabolism*
  6. Fulltext Amoebic forms of Blastocystis spp. - evidence for a pathogenic role
    Rajamanikam A, Govind SK
    Parasit Vectors, 2013;6(1):295.
    PMID: 24499467 DOI: 10.1186/1756-3305-6-295
    Blastocystis spp. are one of the most prevalent parasites isolated from patients suffering from diarrhea, flatulence, constipation and vomiting. It's pathogenicity and pathophysiology remains controversial to date. Protease activity and amoebic forms have been reported previously in symptomatic isolates but there has been no conclusive evidence provided to correlate the protease activity and any specific life cycle stage of the parasite thus far.
    Matched MeSH terms: Peptide Hydrolases/secretion*; Peptide Hydrolases/chemistry
  7. Fulltext Effect of C/N ratio and media optimization through response surface methodology on simultaneous productions of intra- and extracellular inulinase and invertase from Aspergillus niger ATCC 20611
    Dinarvand M, Rezaee M, Masomian M, Jazayeri SD, Zareian M, Abbasi S, et al.
    Biomed Res Int, 2013;2013:508968.
    PMID: 24151605 DOI: 10.1155/2013/508968
    The study is to identify the extraction of intracellular inulinase (exo- and endoinulinase) and invertase as well as optimization medium composition for maximum productions of intra- and extracellular enzymes from Aspergillus niger ATCC 20611. From two different methods for extraction of intracellular enzymes, ultrasonic method was found more effective. Response surface methodology (RSM) with a five-variable and three-level central composite design (CCD) was employed to optimize the medium composition. The effect of five main reaction parameters including sucrose, yeast extract, NaNO₃, Zn⁺², and Triton X-100 on the production of enzymes was analyzed. A modified quadratic model was fitted to the data with a coefficient of determination (R²) more than 0.90 for all responses. The intra-extracellular inulinase and invertase productions increased in the range from 16 to 8.4 times in the optimized medium (10% (w/v) sucrose, 2.5% (w/v) yeast extract, 2% (w/v) NaNO₃, 1.5 mM (v/v) Zn⁺², and 1% (v/v) Triton X-100) by RSM and from around 1.2 to 1.3 times greater than in the medium optimized by one-factor-at-a-time, respectively. The results of bioprocesses optimization can be useful in the scale-up fermentation and food industry.
    Matched MeSH terms: Glycoside Hydrolases/isolation & purification*; Glycoside Hydrolases/chemistry
  8. Porphyromonas gingivalis peptidylarginine deiminase substrate specificity
    Abdullah SN, Farmer EA, Spargo L, Logan R, Gully N
    Anaerobe, 2013 Oct;23:102-8.
    PMID: 23856045 DOI: 10.1016/j.anaerobe.2013.07.001
    While a group of oral commensals have been implicated in the aetiology of chronic periodontitis; the asaccharolytic Gram negative anaerobe Porphyromonas gingivalis is most commonly reported to be associated with severe forms of the disease. Although a variety of human tissues can produce a number of peptidylarginine deiminase (PAD), enzymes that convert peptide bound arginine residues to citrulline, P. gingivalis is one of the few prokaryotes known to express PAD. Protein and peptide citrullination are important in the development of rheumatoid arthritis and in recent years a number of authors have suggested a possible link between periodontitis and rheumatoid arthritis (RA). Indeed, some have linked P. gingivalis directly to RA via the action of PAD. Accordingly, the prime purpose of this study was to further characterise PAD in P. gingivalis cells particular emphasis on substrate specificity, using arginine containing peptides and RA relevant proteins.
    Matched MeSH terms: Hydrolases/metabolism*; Hydrolases/chemistry
  9. Fulltext Genome wide comprehensive analysis and web resource development on cell wall degrading enzymes from phyto-parasitic nematodes
    Rai KM, Balasubramanian VK, Welker CM, Pang M, Hii MM, Mendu V
    BMC Plant Biol, 2015;15:187.
    PMID: 26232118 DOI: 10.1186/s12870-015-0576-4
    The plant cell wall serves as a primary barrier against pathogen invasion. The success of a plant pathogen largely depends on its ability to overcome this barrier. During the infection process, plant parasitic nematodes secrete cell wall degrading enzymes (CWDEs) apart from piercing with their stylet, a sharp and hard mouthpart used for successful infection. CWDEs typically consist of cellulases, hemicellulases, and pectinases, which help the nematode to infect and establish the feeding structure or form a cyst. The study of nematode cell wall degrading enzymes not only enhance our understanding of the interaction between nematodes and their host, but also provides information on a novel source of enzymes for their potential use in biomass based biofuel/bioproduct industries. Although there is comprehensive information available on genome wide analysis of CWDEs for bacteria, fungi, termites and plants, but no comprehensive information available for plant pathogenic nematodes. Herein we have performed a genome wide analysis of CWDEs from the genome sequenced phyto pathogenic nematode species and developed a comprehensive publicly available database.
    Matched MeSH terms: Glycoside Hydrolases/genetics; Glycoside Hydrolases/metabolism
  10. Fulltext Dehalogenases: From Improved Performance to Potential Microbial Dehalogenation Applications
    Ang TF, Maiangwa J, Salleh AB, Normi YM, Leow TC
    Molecules, 2018 05 07;23(5).
    PMID: 29735886 DOI: 10.3390/molecules23051100
    The variety of halogenated substances and their derivatives widely used as pesticides, herbicides and other industrial products is of great concern due to the hazardous nature of these compounds owing to their toxicity, and persistent environmental pollution. Therefore, from the viewpoint of environmental technology, the need for environmentally relevant enzymes involved in biodegradation of these pollutants has received a great boost. One result of this great deal of attention has been the identification of environmentally relevant bacteria that produce hydrolytic dehalogenases—key enzymes which are considered cost-effective and eco-friendly in the removal and detoxification of these pollutants. These group of enzymes catalyzing the cleavage of the carbon-halogen bond of organohalogen compounds have potential applications in the chemical industry and bioremediation. The dehalogenases make use of fundamentally different strategies with a common mechanism to cleave carbon-halogen bonds whereby, an active-site carboxylate group attacks the substrate C atom bound to the halogen atom to form an ester intermediate and a halide ion with subsequent hydrolysis of the intermediate. Structurally, these dehalogenases have been characterized and shown to use substitution mechanisms that proceed via a covalent aspartyl intermediate. More so, the widest dehalogenation spectrum of electron acceptors tested with bacterial strains which could dehalogenate recalcitrant organohalides has further proven the versatility of bacterial dehalogenators to be considered when determining the fate of halogenated organics at contaminated sites. In this review, the general features of most widely studied bacterial dehalogenases, their structural properties, basis of the degradation of organohalides and their derivatives and how they have been improved for various applications is discussed.
    Matched MeSH terms: Hydrolases/metabolism; Hydrolases/chemistry*
  11. Characterization of quorum sensing genes and N-acyl homoserine lactones in Citrobacter amalonaticus strain YG6
    Kher HL, Krishnan T, Letchumanan V, Hong KW, How KY, Lee LH, et al.
    Gene, 2019 Feb 05;684:58-69.
    PMID: 30321658 DOI: 10.1016/j.gene.2018.10.031
    In the phylum of Proteobacteria, quorum sensing (QS) system is widely driven by synthesis and response of N-acyl homoserine lactone (AHL) signalling molecules. AHL is synthesized by LuxI homologue and sensed by LuxR homologue. Once the AHL concentration achieves a threshold level, it triggers the regulation of target genes. In this study, QS activity of Citrobacter amalonaticus strain YG6 which was isolated from clams was investigated. In order to characterise luxI/R homologues, the genome of C. amalonaticus strain YG6 (4.95 Mbp in size) was sequenced using Illumina MiSeq sequencer. Through in silico analysis, a pair of canonical luxI/R homologues and an orphan luxR homologue were identified and designated as camI, camR, and camR2, respectively. A putative lux box was identified at the upstream of camI. The camI gene was cloned and overexpressed in E. coli BL21 (DE3)pLysS. High-resolution triple quadrupole liquid chromatography mass spectrometry (LC-MS/MS) analysis verified that the CamI is a functional AHL synthase which produced multiple AHL species, namely N‑butyryl‑l‑homoserine lactone (C4-HSL), N‑hexanoyl‑l‑homoserine lactone (C6-HSL), N‑octanoyl‑l‑homoserine lactone (C8-HSL), N‑tetradecanoyl‑l‑homoserine lactone (C14-HSL) and N‑hexadecanoyl‑l‑homoserine lactone (C16-HSL) in C. amalonaticus strain YG6 and camI gene in recombinant E. coli BL21(DE3)pLysS. To our best knowledge, this is the first functional study report of camI as well as the first report describing the production of C14-HSL by C. amalonaticus.
    Matched MeSH terms: Carboxylic Ester Hydrolases/genetics; Carboxylic Ester Hydrolases/metabolism*
  12. Genetic studies of water buffalo blood markers. II. Carbonic anhydrase, esterase D, malate dehydrogenase, and malic enzyme
    Sreetharan K, Mukherjee TK, Tan SG, Selvaraj OS, Barker JS
    Biochem Genet, 1994 Feb;32(1-2):35-8.
    PMID: 8031293
    Matched MeSH terms: Carboxylic Ester Hydrolases/blood; Carboxylic Ester Hydrolases/genetics
  13. Fulltext AidP, a novel N-Acyl homoserine lactonase gene from Antarctic Planococcus sp
    See-Too WS, Ee R, Lim YL, Convey P, Pearce DA, Yin WF, et al.
    Sci Rep, 2017 02 22;7:42968.
    PMID: 28225085 DOI: 10.1038/srep42968
    Planococcus is a Gram-positive halotolerant bacterial genus in the phylum Firmicutes, commonly found in various habitats in Antarctica. Quorum quenching (QQ) is the disruption of bacterial cell-to-cell communication (known as quorum sensing), which has previously been described in mesophilic bacteria. This study demonstrated the QQ activity of a psychrotolerant strain, Planococcus versutus strain L10.15T, isolated from a soil sample obtained near an elephant seal wallow in Antarctica. Whole genome analysis of this bacterial strain revealed the presence of an N-acyl homoserine lactonase, an enzyme that hydrolyzes the ester bond of the homoserine lactone of N-acyl homoserine lactone (AHLs). Heterologous gene expression in E. coli confirmed its functions for hydrolysis of AHLs, and the gene was designated as aidP (autoinducer degrading gene from Planococcus sp.). The low temperature activity of this enzyme suggested that it is a novel and uncharacterized class of AHL lactonase. This study is the first report on QQ activity of bacteria isolated from the polar regions.
    Matched MeSH terms: Carboxylic Ester Hydrolases/classification; Carboxylic Ester Hydrolases/genetics*
  14. Response Surface Methodology Modelling of an Aqueous Two-Phase System for Purification of Protease from Penicillium candidum (PCA 1/TT031) under Solid State Fermentation and Its Biochemical Characterization
    Alhelli AM, Abdul Manap MY, Mohammed AS, Mirhosseini H, Suliman E, Shad Z, et al.
    Int J Mol Sci, 2016 Nov 11;17(11).
    PMID: 27845736
    Penicillium candidum (PCA 1/TT031) synthesizes different types of extracellular proteases. The objective of this study is to optimize polyethylene glycol (PEG)/citrate based on an aqueous two-phase system (ATPS) and Response Surface Methodology (RSM) to purify protease from Penicillium candidum (PCA 1/TT031). The effects of different PEG molecular weights (1500-10,000 g/mol), PEG concentration (9%-20%), concentrations of NaCl (0%-10%) and the citrate buffer (8%-16%) on protease were also studied. The best protease purification could be achieved under the conditions of 9.0% (w/w) PEG 8000, 5.2% NaCl, and 15.9% sodium citrate concentration, which resulted in a one-sided protease partitioning for the bottom phase with a partition coefficient of 0.2, a 6.8-fold protease purification factor, and a yield of 93%. The response surface models displayed a significant (p ≤ 0.05) response which was fit for the variables that were studied as well as a high coefficient of determination (R²). Similarly, the predicted and observed values displayed no significant (p > 0.05) differences. In addition, our enzyme characterization study revealed that Penicillium candidum (PCA 1/TT031) produced a slight neutral protease with a molecular weight between 100 and 140 kDa. The optimal activity of the purified enzyme occurred at a pH of 6.0 and at a temperature of 50 °C. The stability between different pH and temperature ranges along with the effect of chemical metal ions and inhibitors were also studied. Our results reveal that the purified enzyme could be used in the dairy industry such as in accelerated cheese ripening.
    Matched MeSH terms: Peptide Hydrolases/isolation & purification*; Peptide Hydrolases/chemistry
  15. Fulltext Optimizing culture conditions for production of intra and extracellular inulinase and invertase from Aspergillus niger ATCC 20611 by response surface methodology (RSM)
    Dinarvand M, Rezaee M, Foroughi M
    Braz J Microbiol, 2017 Jul-Sep;48(3):427-441.
    PMID: 28359854 DOI: 10.1016/j.bjm.2016.10.026
    The aim of this study was obtain a model that maximizes growth and production of inulinase and invertase by Aspergillus niger ATCC 20611, employing response surface methodology (RSM). The RSM with a five-variable and three-level central composite design (CCD) was employed to optimize the medium composition. Results showed that the experimental data could be appropriately fitted into a second-order polynomial model with a coefficient of determination (R2) more than 0.90 for all responses. This model adequately explained the data variation and represented the actual relationships between the parameters and responses. The pH and temperature value of the cultivation medium were the most significant variables and the effects of inoculum size and agitation speed were slightly lower. The intra-extracellular inulinase, invertase production and biomass content increased 10-32 fold in the optimized medium condition (pH 6.5, temperature 30°C, 6% (v/v), inoculum size and 150rpm agitation speed) by RSM compared with medium optimized through the one-factor-at-a-time method. The process development and intensification for simultaneous production of intra-extracellular inulinase (exo and endo inulinase) and invertase from A. niger could be used for industrial applications.
    Matched MeSH terms: Glycoside Hydrolases/biosynthesis*; Glycoside Hydrolases/genetics
  16. Neutralization of Burkholderia pseudomallei protease by Fabs generated through phage display
    Nathan S, Rader C, Barbas CF
    Biosci Biotechnol Biochem, 2005 Dec;69(12):2302-11.
    PMID: 16377887
    The isolation of therapeutic and functional protease inhibitors in vitro via combinatorial chemistry and phage display technology has been described previously. Here we report the construction of a combinatorial mouse-human chimeric antibody fragment (Fab) antibody library targeted against the protease of the tropical pathogen, Burkholderia pseudomallei. The resulting library was biopanned against the protease, and selected clones were analyzed for their ability to function as protease inhibitors. Three families of Fabs were identified by restriction fingerprinting, all of which demonstrated high specificity towards the protease of B. pseudomallei. Purified Fabs also demonstrated the capacity to inhibit B. pseudomallei protease activity in vitro, and this inhibitory property was exclusive to the pathogenic protease. Thus these recombinant antibodies are candidates for immunotherapy and tools to aid in further elucidation of the mechanism of action of the B. pseudomallei protease.
    Matched MeSH terms: Peptide Hydrolases/immunology; Peptide Hydrolases/chemistry*
  17. ProLysED: an integrated database and meta-server of bacterial protease systems
    Firdaus Raih M, Ahmad HA, Sharum MY, Azizi N, Mohamed R
    Appl. Bioinformatics, 2005;4(2):147-50.
    PMID: 16128617
    Bacterial proteases are an important group of enzymes that have very diverse biochemical and cellular functions. Proteases from prokaryotic sources also have a wide range of uses, either in medicine as pathogenic factors or in industry and therapeutics. ProLysED (Prokaryotic Lysis Enzymes Database), our meta-server integrated database of bacterial proteases, is a useful, albeit very niche, resource. The features include protease classification browsing and searching, organism-specific protease browsing, molecular information and visualisation of protease structures from the Protein Data Bank (PDB) as well as predicted protease structures.
    Matched MeSH terms: Peptide Hydrolases/classification; Peptide Hydrolases/chemistry*
  18. Fulltext The characterisation of an alkali-stable maltogenic amylase from Bacillus lehensis G1 and improved malto-oligosaccharide production by hydrolysis suppression
    Abdul Manas NH, Pachelles S, Mahadi NM, Illias RM
    PLoS One, 2014;9(9):e106481.
    PMID: 25221964 DOI: 10.1371/journal.pone.0106481
    A maltogenic amylase (MAG1) from alkaliphilic Bacillus lehensis G1 was cloned, expressed in Escherichia coli, purified and characterised for its hydrolysis and transglycosylation properties. The enzyme exhibited high stability at pH values from 7.0 to 10.0. The hydrolysis of β-cyclodextrin (β-CD) produced malto-oligosaccharides of various lengths. In addition to hydrolysis, MAG1 also demonstrated transglycosylation activity for the synthesis of longer malto-oligosaccharides. The thermodynamic equilibrium of the multiple reactions was shifted towards synthesis when the reaction conditions were optimised and the water activity was suppressed, which resulted in a yield of 38% transglycosylation products consisting of malto-oligosaccharides of various lengths. Thin layer chromatography and high-performance liquid chromatography analyses revealed the presence of malto-oligosaccharides with a higher degree of polymerisation than maltoheptaose, which has never been reported for other maltogenic amylases. The addition of organic solvents into the reaction further suppressed the water activity. The increase in the transglycosylation-to-hydrolysis ratio from 1.29 to 2.15 and the increased specificity toward maltopentaose production demonstrated the enhanced synthetic property of the enzyme. The high transglycosylation activity of maltogenic amylase offers a great advantage for synthesising malto-oligosaccharides and rare carbohydrates.
    Matched MeSH terms: Glycoside Hydrolases/metabolism; Glycoside Hydrolases/chemistry*
  19. Fulltext Application of membrane-based technology for purification of bromelain
    Nor, M. Z. M., Ramchandran, L., Duke, M., Vasiljevic, T.
    International Food Research Journal, 2017;24(4):1685-1696.
    MyJurnal
    About 60% of world’s commercial enzyme products are proteases, giving promising opportunity
    to derive such enzymes sustainably from waste sources. Bromelain is a crude protease occurring
    naturally in pineapple, and it possesses properties of benefit for pharmaceutical, medical and food products. The production of bromelain involves a purification stage, normally performed by small-scale conventional operations which lead to high operating cost and low product recovery, while being difficult to scale up and produce polluting by-products. Membrane-based technology offers an alternative to produce high quality purified bromelain in a more efficient and sustainable process. This review identified the current state and future needs for utilising membrane processes for sustainable bromelain production at larger scales. It was found that declining membrane flux due to fouling have been reported, but may be effectively overcome with more appropriate (and advanced) membrane types and/or processing conditions. For example, interactions between macromolecules present in the pineapple derived bromelain mixture (particularly polysaccharides) and the membrane may cause performance limiting fouling, but can be overcome by enzymatic pre-treatment. Membrane fouling can be further reduced by the employment of ceramic membrane filters operating at optimised trans-membrane pressure, cross-flow velocity, feed pH and temperature. Two-stage ultrafiltration together with diafiltration or gas sparging was suggested as a means to reduce fouling and improve enzyme purity. Despite these promising technical findings, the review identified the need for a valid economic assessment to properly guide further work towards purifying bromelain from pineapple waste for sustainable production of commercial proteases.
    Matched MeSH terms: Peptide Hydrolases
  20. Fulltext Near real-time biomonitoring of copper from an industrial complex effluent discharge site using a plant protease inhibitive assay
    Halmi, M.I.E., Khayat, M.E., Rahman, M.F.A., Gunasekaran, B., Masdor, N.A.
    Bioremediation Science and Technology Research, 2016;4(1):10-13.
    MyJurnal
    In this work, a temporal monitoring work for heavy metals from an effluent discharge point in
    the Juru Industrial Estate was carried out using the protease extracted from garlic (Allium
    sativum) as the principal bioassay system. casein-Coomassie-dye binding assay method has
    utilized this purpose. The periodic sampling results for one day of a location in the Juru
    Industrial Estate showed temporal variation of copper concentration coinciding with garlic
    protease inhibition with the highest concentrations of copper occurring between 12.00 and 16.00
    hours of between 3 and 3.5 mg/L copper. The crude proteases extracted from Allium sativum
    successfully detect temporal variation of copper form this location. In conclusion, this assay
    method has the potential to be a rapid, sensitive, and economic inhibitive assay for the largescale
    biomonitoring works for the heavy metal copper from this area.
    Matched MeSH terms: Peptide Hydrolases
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