Displaying publications 61 - 80 of 126 in total

Abstract:
Sort:
  1. Lorrine OE, Rahman RNZRA, Joo Shun T, Salleh AB, Oslan SN
    Anal Biochem, 2023 May 01;668:115092.
    PMID: 36889624 DOI: 10.1016/j.ab.2023.115092
    In eukaryotes, serine proteases are cellular localized hydrolases reported to regulate essential biological reactions. Improved industrial applications of proteins are aided by prediction and analysis of their 3-dimensional structures (3D). A serine protease was identified from CTG-clade yeast Meyerozyma guilliermondii strain SO and its 3D structure as well as its catalytic attributes have not been fully understood yet, thus we seek to report on the catalytic mechanism of M. guilliermondii strain SO MgPRB1 using substrate PMSF via in silico docking as well as its stability by way of disulfide bonds formation. Herein, bioinformatics tools and techniques were used to predict, validate and analyze the possible changes of CUG ambiguity (if any) in strain SO using template PDB ID: 3F7O. Structural assessments confirmed the classic catalytic triad Asp305, His337, and Ser499. Superimposition of MgPRB1 and template 3F7O structures revealed the unlinked cysteine residues between Cys341, Cys440, Cys471 and Cys506 of MgPRB1 compared to template 3F7O with two disulfide bonds formation, which confers structural stability. In conclusion, serine protease structure from strain SO was successfully predicted and studies towards understanding at the molecular level may be undertaken for its potential applications in the degradation of peptide bonds.
    Matched MeSH terms: Serine Endopeptidases
  2. Low CF, Chong PP, Yong PV, Lim CS, Ahmad Z, Othman F
    J Appl Microbiol, 2008 Dec;105(6):2169-77.
    PMID: 19120662 DOI: 10.1111/j.1365-2672.2008.03912.x
    The aims of the present study were to determine whether Allium sativum (garlic) extract has any effect on the morphology transformation of Candida albicans, and to investigate whether it could alter the gene expression level of SIR2, a morphogenetic control gene and SAP4, a gene encoding secreted aspartyl proteinase.
    Matched MeSH terms: Aspartic Acid Endopeptidases/genetics; Aspartic Acid Endopeptidases/metabolism
  3. Lye SH, Chahil JK, Bagali P, Alex L, Vadivelu J, Ahmad WA, et al.
    PLoS One, 2013;8(4):e60729.
    PMID: 23593297 DOI: 10.1371/journal.pone.0060729
    Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by elevations in total cholesterol (TC) and low density lipoprotein cholesterol (LDLc). Development of FH can result in the increase of risk for premature cardiovascular diseases (CVD). FH is primarily caused by genetic variations in Low Density Lipoprotein Receptor (LDLR), Apolipoprotein B (APOB) or Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) genes. Although FH has been extensively studied in the Caucasian population, there are limited reports of FH mutations in the Asian population. We investigated the association of previously reported genetic variants that are involved in lipid regulation in our study cohort. A total of 1536 polymorphisms previously implicated in FH were evaluated in 141 consecutive patients with clinical FH (defined by the Dutch Lipid Clinic Network criteria) and 111 unrelated control subjects without FH using high throughput microarray genotyping platform. Fourteen Single Nucleotide Polymorphisms (SNPs) were found to be significantly associated with FH, eleven with increased FH risk and three with decreased FH risk. Of the eleven SNPs associated with an increased risk of FH, only one SNP was found in the LDLR gene, seven in the APOB gene and three in the PCSK9 gene. SNP rs12720762 in APOB gene is associated with the highest risk of FH (odds ratio 14.78, p<0.001). Amongst the FH cases, 108 out of 141 (76.60%) have had at least one significant risk-associated SNP. Our study adds new information and knowledge on the genetic polymorphisms amongst Asians with FH, which may serve as potential markers in risk prediction and disease management.
    Matched MeSH terms: Serine Endopeptidases/genetics*
  4. Ma TH, Benzie JA, He JG, Sun CB, Chan SF
    Dev Comp Immunol, 2014 May;44(1):163-72.
    PMID: 24345607 DOI: 10.1016/j.dci.2013.12.007
    One of the major steps in the innate immune response of shrimp includes the activation of serine proteinases of the pro-phenoloxidase pathway by the prophenoloxidase activation enzyme (PPAF). In this study, the cDNA encoding a serine proteinase homologue (SPH) with prophenoloxidase activating activity of Penaeus monodon (PmPPAF) was cloned and characterized. PmPPAF cDNA consists of 1444 nucleotides encoding a protein with 394 amino acid residues. The estimated molecular weight of PmPPAF is 43.5 kDa with an isoelectric point of 5.19. PmPPAF consists of a signal peptide, a CLIP domain and a carboxyl-terminal trypsin-like serine protease domain. It is highly similar to the masquerade-like protein 2A (61% similarity) of the crayfish Pacifastacus leniusculus, other serine proteases (42.9-67% identity) of P. monodon, and the PPAF of the crab (61% similarity). Unlike other SPH of P. monodon, which express mainly in the hemocytes, PmPPAF transcripts were detected in the hemocytes, eyestalk, hypodermis, gill, swimming leg and brain. Similar to the crab PPAF, PmPPAF transcript level is high in shrimp at the premolt stages and PmPPAF expression is up-regulated in shrimp infected with white spot syndrome virus (WSSV). Gene silencing of PmPPAF decreased expression of a prophenoloxidase-like gene and injection of Anti-PmPPAF antibody causes a decrease in PO activity. Taken together, these results provided evidence that PmPPAF is a serine proteinase homologue, and is involved in the pro-PO activation pathway of the shrimp innate immune system.
    Matched MeSH terms: Serine Endopeptidases/genetics; Serine Endopeptidases/metabolism*
  5. Mahmoodani F, Ghassem M, Babji AS, Yusop SM, Khosrokhavar R
    J Food Sci Technol, 2014 Sep;51(9):1847-56.
    PMID: 25190839 DOI: 10.1007/s13197-012-0742-8
    Skin and bone gelatins of pangasius catfish (Pangasius sutchi) were hydrolyzed with alcalase to isolate Angiotensin Converting Enzyme (ACE) inhibitory peptides. Samples with the highest degree of hydrolysis (DH) were separated into different fractions with molecular weight cut-off (MWCO) sizes of 10, 3 and 1 kDa, respectively and assayed for ACE inhibitory activity. Skin and bone gelatins had highest DH of 64.87 and 68.48 % after 2 and 1 h incubation, respectively. Results from this study indicated that by decreasing the molecular weight of fractions, ACE inhibitory activity was increased. Therefore, F3 permeates (MWCO 
    Matched MeSH terms: Endopeptidases
  6. Mai CW, Chung FF, Leong CO
    Curr Drug Targets, 2017;18(11):1259-1268.
    PMID: 27993111 DOI: 10.2174/1389450117666161216125344
    BACKGROUND: Recent reports indicate that the tumor microenvironment plays a pivotal role in cancer development and progression, leading to a paradigm shift in the way cancer is studied and targeted. In contrast to traditional approaches, where only tumor cells are targeted for the treatment, an emerging approach is to develop therapeutics which target the tumor microenvironment while complementing or enhancing current treatments. Legumain (LGMN) is a newly identified target which is highly expressed in the tumor microenvironment and in tumor cells, and holds potential both as a biomarker and as a therapeutic target.

    CONCLUSION: This review will be the first to summarize the expression of LGMN in common cancers, as well as its roles in tumorigenesis and metastasis. This review also discusses the current developments and future prospects of targeting LGMN through the development of DNA vaccines, azopeptides, small molecule inhibitors and LGMN activated prodrugs, highlighting the potential of LGMN as a target for cancer therapeutics.

    Matched MeSH terms: Cysteine Endopeptidases/metabolism*
  7. Mani V, Ramasamy K, Ahmad A, Parle M, Shah SA, Majeed AB
    Food Chem Toxicol, 2012 Mar;50(3-4):1036-44.
    PMID: 22142688 DOI: 10.1016/j.fct.2011.11.037
    Dementia is a syndrome of gradual onset and continuous decline of higher cognitive functioning. It is a common disorder in older persons and has become more prevalent today. The fresh leaves of Murraya koenigii are often added to various dishes in Asian countries due to the delicious taste and flavor that they impart. These leaves have also been proven to have health benefits. In the present study, the effect of total alkaloidal extract from M. koenigii leaves (MKA) on cognitive functions and brain cholinesterase activity in mice were determined. In vitro β-secretase 1 (BACE1) inhibitory activity was also evaluated. The total alkaloidal extract was administered orally in three doses (10, 20 and 30 mg/kg) for 15 days to different groups of young and aged mice. Elevated plus maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam-, scopolamine-, and ageing-induced amnesia served as the interoceptive behavioral models. MKA (20 and 30 mg/kg, p.o.) showed significant improvement in memory scores of young and aged mice. Furthermore, the same doses of MKA reversed the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Interestingly, the brain cholinesterase activity was also reduced significantly by total alkaloidal extract of M. koenigii leaves. The IC50 value of MKA against BACE1 was 1.7 μg/mL. In conclusion, this study indicates MKA to be a useful remedy in the management of Alzheimer's disease and dementia.
    Matched MeSH terms: Aspartic Acid Endopeptidases/antagonists & inhibitors
  8. Mat Amin N
    Trop Biomed, 2004 Dec;21(2):57-60.
    PMID: 16493399
    Naegleria fowleri is a free-living amoeba, known as a causative agent for a fatal disease of the central nervous system (CNS) in man such as Primary amoebic meningoencephalitis (PAM). Factors contributing to its pathogenicity and its distribution in the environment have been investigated by previous researchers. In case of its pathogenicity, several enzymes such as phospolipase A and sphingomyelinase, have been proposed to probably act as aggressors in promoting PAM but no study so far have been conducted to investigate the presence of proteinase enzyme in this amoeba although a 56kDa cystein proteinase enzyme has been identified in Entamoeba histolytica as an important contributing factor in the amoeba's virulence. In this preliminary study, a pathogenic amoeba, Naegleria fowleri (strain NF3) was examined for the presence of proteinases. Samples of enzymes in this amoeba were analysed by electrophoresis using SDS-PAGE-gelatin gels. The results showed that this amoeba possesses at least two high molecular weight proteinases on gelatin gels; their apparent molecular weights are approximately 128 kDa and approximately 170 kDa. Band of approximately 128 kDa enzyme is membrane-associated and its activity is higher at alkaline pH compared with lower pH; at lower pH, its activity is greatly stimulated by DTT. The approximately 170 kDa band enzyme appears to be inactivated at pH 8.0, at lower ph its activity is higher and DTT-dependance. The activity of this enzyme is partially inhibited by inhibitor E-64 but markedly inhibited to antipain suggesting it belongs to the cysteine proteinase group.
    Matched MeSH terms: Endopeptidases
  9. Mazlyzam AL, Aminuddin BS, Saim L, Ruszymah BH
    Med J Malaysia, 2008 Jul;63 Suppl A:32-3.
    PMID: 19024969
    The angiogenic potential of native skin (NS), keratinocytes single skin equivalent (SSE-K), fibroblasts single skin equivalent (SSE-F) and bilayered skin equivalent secreting angiogenic growth factors such as transforming growth factor beta1 (TGF-beta1), vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF) and basic fibroblast growth factor (bFGF) in the in vitro systems at 24, 48, 72 hours and 7 days was compared using Enzyme-Linked Immunosorbent Assay (ELISA). Bilayered skin equivalent exhibit highest release of growth factors within 24 hours to 7 days of culture compared to NS, SSE-K and SSE-F. This proved the potential of bilayered skin equivalent in producing and sustaining growth factors release to enhance angiogenesis, fibroblasts proliferation, matrix deposition, migration and growth of keratinocytes.
    Matched MeSH terms: Serine Endopeptidases
  10. Mechri S, Allala F, Bouacem K, Hasnaoui I, Gwaithan H, Chalbi TB, et al.
    Int J Biol Macromol, 2022 Dec 01;222(Pt A):1326-1342.
    PMID: 36242508 DOI: 10.1016/j.ijbiomac.2022.09.161
    We recently described the production of a detergent-biocompatible crude protease from Streptomyces mutabilis strain TN-X30. Here, we describe the purification, characterization, and immobilization of the serine alkaline protease (named SPSM), as well as the cloning, sequencing, and over-expression of its corresponding gene (spSM). Pure enzyme was obtained after ammonium sulphate precipitation followed by heat-treatment and Sephacryl® S-200 column purification. The sequence of the first 26 NH2-terminal residues of SPSM showed a high sequence identity to subtilisin-like serine proteases produced by actinobacteria. The spSM gene was heterologously expressed in Escherichia coli BL21(DE3)pLysS and E. coli BL21-AI™ strains using pTrc99A (rSPSM) and Gateway™ pDEST™ 17 [(His)6-tagged SPSM] vectors, respectively. Results obtained indicated that the (His)6-tagged SPSM showed the highest stability. The SPSM was immobilized using encapsulation and adsorption-encapsulation approaches and three different carriers. Features of SPSM in soluble and immobilized forms were analyzed by Fourier transform infrared (FTIR) spectroscopy in attenuated total reflection (ATR) mode, X-ray diffraction (XRD), zeta potential measurements, and field emission scanning electron microscopy (FE-SEM). The white clay and kaolin used in this study are eco-friendly binders to alginate-SPSM and show great potential for application of the immobilized SPSM in various industries. Molecular modeling and docking of N-succinyl-l-Phe-l-Ala-l-Ala-l-Phe-p-nitroanilide in the active site of SPSM revealed the involvement of 21 amino acids in substrate binding.
    Matched MeSH terms: Serine Endopeptidases/metabolism
  11. Mirsafian H, Mat Ripen A, Merican AF, Bin Mohamad S
    ScientificWorldJournal, 2014;2014:482463.
    PMID: 25254246 DOI: 10.1155/2014/482463
    Beta-amyloid precursor protein cleavage enzyme 1 (BACE1) and beta-amyloid precursor protein cleavage enzyme 2 (BACE2), members of aspartyl protease family, are close homologues and have high similarity in their protein crystal structures. However, their enzymatic properties differ leading to disparate clinical consequences. In order to identify the residues that are responsible for such differences, we used evolutionary trace (ET) method to compare the amino acid conservation patterns of BACE1 and BACE2 in several mammalian species. We found that, in BACE1 and BACE2 structures, most of the ligand binding sites are conserved which indicate their enzymatic property of aspartyl protease family members. The other conserved residues are more or less randomly localized in other parts of the structures. Four group-specific residues were identified at the ligand binding site of BACE1 and BACE2. We postulated that these residues would be essential for selectivity of BACE1 and BACE2 biological functions and could be sites of interest for the design of selective inhibitors targeting either BACE1 or BACE2.
    Matched MeSH terms: Aspartic Acid Endopeptidases/genetics*; Aspartic Acid Endopeptidases/metabolism; Aspartic Acid Endopeptidases/chemistry
  12. Mirza FJ, Zahid S, Amber S, Sumera, Jabeen H, Asim N, et al.
    Molecules, 2022 Oct 25;27(21).
    PMID: 36364071 DOI: 10.3390/molecules27217241
    Alzheimer's disease (AD) has been associated with the hallmark features of cholinergic dysfunction, amyloid beta (Aβ) aggregation and impaired synaptic transmission, which makes the associated proteins, such as β-site amyloid precursor protein cleaving enzyme 1 (BACE I), acetylcholine esterase (AChE) and synapsin I, II and III, major targets for therapeutic intervention. The present study investigated the therapeutic potential of three major phytochemicals of Rosmarinus officinalis, ursolic acid (UA), rosmarinic acid (RA) and carnosic acid (CA), based on their binding affinity with AD-associated proteins. Detailed docking studies were conducted using AutoDock vina followed by molecular dynamic (MD) simulations using Amber 20. The docking analysis of the selected molecules showed the binding energies of their interaction with the target proteins, while MD simulations comprising root mean square deviation (RMSD), root mean square fluctuation (RMSF) and molecular mechanics/generalized born surface area (MM/GBSA) binding free energy calculations were carried out to check the stability of bound complexes. The drug likeness and the pharmacokinetic properties of the selected molecules were also checked through the Lipinski filter and ADMETSAR analysis. All these bioactive compounds demonstrated strong binding affinity with AChE, BACE1 and synapsin I, II and III. The results showed UA and RA to be potential inhibitors of AChE and BACE1, exhibiting binding energies comparable to those of donepezil, used as a positive control. The drug likeness and pharmacokinetic properties of these compounds also demonstrated drug-like characteristics, indicating the need for further in vitro and in vivo investigations to ascertain their therapeutic potential for AD.
    Matched MeSH terms: Aspartic Acid Endopeptidases
  13. Mukhametov A, Newhouse EI, Aziz NA, Saito JA, Alam M
    J Mol Graph Model, 2014 Jul;52:103-13.
    PMID: 25023665 DOI: 10.1016/j.jmgm.2014.06.008
    The allosteric pocket of the Dengue virus (DENV2) NS2B/NS3 protease, which is proximal to its catalytic triad, represents a promising drug target (Othman et al., 2008). We have explored this binding site through large-scale virtual screening and molecular dynamics simulations followed by calculations of binding free energy. We propose two mechanisms for enzyme inhibition. A ligand may either destabilize electronic density or create steric effects relating to the catalytic triad residues NS3-HIS51, NS3-ASP75, and NS3-SER135. A ligand may also disrupt movement of the C-terminal of NS2B required for inter-conversion between the "open" and "closed" conformations. We found that chalcone and adenosine derivatives had the top potential for drug discovery hits, acting through both inhibitory mechanisms. Studying the molecular mechanisms of these compounds might be helpful in further investigations of the allosteric pocket and its potential for drug discovery.
    Matched MeSH terms: Serine Endopeptidases/metabolism*
  14. Nabil Fikri RM, Norlelawati AT, Nour El-Huda AR, Hanisah MN, Kartini A, Norsidah K, et al.
    J Psychiatr Res, 2017 05;88:28-37.
    PMID: 28086126 DOI: 10.1016/j.jpsychires.2016.12.020
    The epigenetic changes of RELN that are involved in the development of dopaminergic neurons may fit the developmental theory of schizophrenia. However, evidence regarding the association of RELN DNA methylation with schizophrenia is far from sufficient, as studies have only been conducted on a few limited brain samples. As DNA methylation in the peripheral blood may mirror the changes taking place in the brain, the use of peripheral blood for a DNA methylation study in schizophrenia is feasible due to the scarcity of brain samples. Therefore, the aim of our study was to examine the relationship of DNA methylation levels of RELN promoters with schizophrenia using genomic DNA derived from the peripheral blood of patients with the disorder. The case control studies consisted of 110 schizophrenia participants and 122 healthy controls who had been recruited from the same district. After bisufhite conversion, the methylation levels of the DNA samples were calculated based on their differences of the Cq values assayed using the highly sensitive real-time MethyLight TaqMan® procedure. A significantly higher level of methylation of the RELN promoter was found in patients with schizophrenia compared to controls (p = 0.005) and also in males compared with females (p = 0.004). Subsequently, the RELN expression of the methylated group was 25 fold less than that of the non-methylated group. Based upon the assumption of parallel methylation changes in the brain and peripheral blood, we concluded that RELN DNA methylation might contribute to the pathogenesis of schizophrenia. However, the definite effects of methylation on RELN function during development and also in adult life still require further elaboration.
    Matched MeSH terms: Serine Endopeptidases/blood*; Serine Endopeptidases/genetics*
  15. Nafi’, A., Foo, H.L., Jamilah, B., Ghazali. H.M.
    MyJurnal
    Proteases in ginger rhizome have the potentials in industrial applications. This study was conducted to extract and characterize the proteolytic enzyme from ginger (Zingiber officinale Roscoe). Ginger protease (GP) was extracted from ginger rhizome by homogenization with 100 mM potassium phosphate buffer pH 7.0 containing 10 mM cysteine and 5 mM EDTA which were found to be the most efficient extraction buffer and stabilizers. After centrifugation at 10,500 x g, protein in the crude extract was precipitated using 60% ammonium sulfate following which the precipitate was redissolved in 50 mM potassium phosphate buffer pH 7.0, dialyzed and then lyophilized. The extraction method yielded 0.94% (w/w of fresh weight) of GP with a specific activity of 27.6 ± 0.1 Unit/mg protein where 1 Unit is defined as the amount of protease causing an increase in absorbance by 1 unit per minute using azocasein as the substrate. Results show that the GP was completely inhibited by heavy metal cations i.e. Cu2+and Hg2+, and a thiol blocking agent or inhibitor, n-ethyl maleimide (NEM), indicating that GP is most probably a cysteine protease. The enzyme has an optimum temperature at 60⁰C and the optimum pH ranged between pH 6 to 8. Monovalent cations (K+ and Na+) have no significant effect on activity of GP, but divalent and trivalent cations showed moderate inhibitory effect. Detergents such as sodium dodecyl sulfate increased the activity of GP while Tween 80 and Tween 20 slightly reduced the activity.
    Matched MeSH terms: Endopeptidases
  16. Natarajan S
    Genet Mol Biol, 2010 Apr;33(2):214-9.
    PMID: 21637471 DOI: 10.1590/S1415-47572010000200002
    The development of novel therapeutic agents is essential for combating the increasing number of cases of dengue fever in endemic countries and among a large number of travelers from non-endemic countries. The dengue virus has three structural proteins and seven non-structural (NS) proteins. NS3 is a multifunctional protein with an N-terminal protease domain (NS3pro) that is responsible for proteolytic processing of the viral polyprotein, and a C-terminal region that contains an RNA triphosphatase, RNA helicase and RNA-stimulated NTPase domain that are essential for RNA replication. The serine protease domain of NS3 plays a central role in the replicative cycle of dengue virus. This review discusses the recent structural and biological studies on the NS2B-NS3 protease-helicase and considers the prospects for the development of small molecules as antiviral drugs to target this fascinating, multifunctional protein.
    Matched MeSH terms: Serine Endopeptidases
  17. Noorul Aini Sulaiman, Nur Zazarina Ramly, Shuhaila Mat-Sharani, Nor Muhammad Mahadi
    MyJurnal
    Protease is an enzyme that catalysed the hydrolysis of protein into peptide. Application of protease in industry has been linked with cost effective substrates and complex of enzyme-substrate stability. Molecular docking approach has identified casein as a preference substrates. However, lack of data on casein mode of binding to protease and enzyme stability represents a limitation for its production and structural optimization. In this study, we have used a molecular dynamic (MD) to examine the stability of complex enzyme-substrate of protease from Bacillus lehensis G1. The 3D structure of protease (BleG1_1979) was docked with substrate casein using AutoDock Vina. Structural analysis of the substrate-binding cleft revealed a binding site of casein was predominantly at the hydrophobic region of BleG1_1979. The MD of complex BleG1_1979-casein was tested with two temperatures; 298 K and 310 K using GROMACS v5.1.4. MD simulation showed a stable behaviour of BleG1_1979 over the 20 ns simulation period. The molecular docking and MD simulation suggested that the production of protease from B. lehensis G1 by utilization of casein and the stability of complex protease-casein could be a potential application to generate a cost effective enzyme to be develop for industrial use.
    Matched MeSH terms: Endopeptidases
  18. Nor, M. Z. M., Ramchandran, L., Duke, M., Vasiljevic, T.
    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: Endopeptidases
  19. Normah Ismail, Nurulain Abd Razak
    MyJurnal
    Protease was extracted from two maturity stages of noni fruits (Morinda citrifolia L.), unripe (stage 1) and ripe (stage 5). The crude extract was partially purified by acetone precipitation method followed by dialysis, gel filtration chromatography and freeze drying. Protein concentrations, proteolytic activity, molecular weight distribution, pH stability, temperature stability and storage efficiency of the resulting protease were evaluated. The unripe and ripe noni fruit contains 0.65 and 0.35% protein, respectively. Molecular weight of the proteases from both stages ranged approximately between 3 to 28 kDa based on the SDS-PAGE results. The optimum activity were at pH 7s and 6, temperatures of 40 and 50°C, respectively for proteases obtained from the unripe and ripe fruit. Analysis from the freeze dried protease indicated that protease from ripe noni fruits had higher protein concentration and specific activity compared to those from unripe fruit. However, it is more sensitive to pH and temperature and less stable during storage as it shows lower proteolytic activity compared to protease from unripe fruit. Based on its high proteolytic activity reaching up to 70.31 U/mg and storage stability (30% lost of activity), noni fruit could be an alternative source of plant protease.
    Matched MeSH terms: Endopeptidases
  20. Normah Ismail, Juliana Mahmod, Awatif Khairul Fatihin Mustafa Kamal
    MyJurnal
    In this study, Hydrolysate from angelwing clam (Pholas orientalis) was produced at 0, 1, 2 and 3 hrs and E/S ratio of 0.5 and 3% using alcalase where the pH and temperature were kept constant at pH 8.5 and 60°C, respectively. The hydrolysates were analysed for antioxidant and functional properties such as solubility, emulsifying properties and water and oil holding capacity. Degree of hydrolysis (DH), yield, functional and antioxidant properties were influenced by the hydrolysis time and E/S ratio. Higher enzyme concentration (E/S 3%) and longer hydrolysis time increased the DH. Yield was higher at E/S 3% but reduced with hydrolysis time. Longer hydrolysis time produced more soluble hydrolysate and higher metal chelating activity but lower in emulsifying properties and DPPH activity. Higher enzyme concentration resulted in increase only in solubility and metal chelating activity. This study revealed that enzymatic hydrolysis using alcalase should be performed at shorter hydrolysis time using intermediate concentration of enzyme (E/S between 0.5 to 3%) in order to produce angelwing clam hydrolysate with collectively good functional and antioxidant properties
    Matched MeSH terms: Endopeptidases
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links