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Effect of heating on oxidation stability and fatty acid composition of microwave roasted groundnut seed oil

Abbas Ali M, Anowarul Islam M, Othman NH, Noor AM

J Food Sci Technol, 2017 Dec;54(13):4335-4343.
PMID: 29184239 DOI: 10.1007/s13197-017-2904-1

The oxidative stability and fatty acid composition of groundnut seed oil (GSO) exposed to microwaves were evaluated during heating at 170 °C. During heating, the oxidative indices such as free fatty acid, peroxide value, p-anisidine value, TOTOX, thiobarbituric acid value, specific extinctions, and color value were increased. The increments were found to be higher in unroasted seed oils compared to roasted ones indicating lower release of lipid oxidation products in roasted GSO. After 9 h heating, the relative content of polyunsaturated fatty acid (PUFA) decreased to 89.53% and that of saturated fatty acid (SFA) increased to 117.46% in unroasted sample. The relative content of PUFA decreased to 92.05% and that of SFA increased to 105.76% in 7.5 min roasted sample after 9 h of heating. However, the roasting process slowed down the oxidative deterioration of PUFA. With increased heating times, an appreciable loss was more apparent in the triacylglycerol species OLL and OOL in unroasted samples compared to roasted ones. In FTIR, the peak intensities in unroasted samples were markedly changed in comparison with roasted samples during heating. The roasting of groundnut seed prior to the oil extraction reduced the oxidative degradation of oil samples; thereby increasing heat stability.
Microleakage assessment of a repaired, nano-filled, resin-based fissure sealant

Qadri GW, Noor SN, Mohamad D

Pediatr Dent, 2009 Sep-Oct;31(5):389-94.
PMID: 19947133

The purpose of this study was to evaluate the effects of different repairing techniques of a fractured sealant on microleakage in vitro.
Fulltext Utilization of dental general anaesthesia for children

Karim ZA, Musa N, Noor SN

Malays J Med Sci, 2008 Jul;15(3):31-9.
PMID: 22570587 MyJurnal

Dental treatment under general anaesthesia may be needed for some children and adolescents due to medical or behaviour problem. The objective of the study is to identify the type of treatment that has been carried out under GA in Hospital Universiti Sains Malaysia (HUSM). A retrospective record review study from hospital records of dental patients (under 18 years old) receiving dental treatment under GA from 2003 until 2007 were retrieved from the database. Information such as the reason for GA, and the type of treatment provided was recorded in data sheet. The data were analyzed using SPSS 12.0.1 for Windows. It was checked and verified for errors. A total of 349 cases were treated of which 43.6% had medical problems. Patients were mostly diagnosed to have rampant caries (77.1%) and some of them have behavioural problems (34.4%). Treatment pattern in deciduous dentition revealed more extraction (97.8%) as compared to restoration (75.7%) whereas in permanent dentition more restoration was done (24.3%) as compared to extraction (2.2%). Majority of the restorations were done using Glass Ionomer Cements (47.5%). Biopsy (4.3%) contributed mainly to the surgery (24.1%) done during GA. General anesthesia is necessary when dental disease is interfering with health and general well-being of patient and it can facilitated dental treatment allowing dentists to benefit from improved treatment conditions and provide a higher quality of care.
Characteristics of ABO Antibodies in Group O Malaysian Blood Donors

Saidin NIS, Noor NHM, Yusoff SM, Sauli MS

Malays J Med Sci, 2023 Aug;30(4):61-70.
PMID: 37655148 DOI: 10.21315/mjms2023.30.4.6

BACKGROUND: Haemolytic transfusion reactions (HTRs) due to anti-A and anti-B antibodies in Group O blood products are rare but potentially fatal. This study aimed to identify the prevalence of high ABO antibody titre and the immunoglobulin (Ig) classes (IgM only or with IgG) and the prevalence of haemolysin antibodies in Group O blood donors.
METHODS: Plasma from Group O blood donors was tested by using antibody titration at room temperature. Titres ≥ 64 were considered high. The plasma was treated with 0.01 M dithiothreitol (DTT) to determine the presence of IgG antibodies and titre. IgG titres ≥ 64 were considered high. Tests for haemolysis were conducted by mixing the plasma with 3% fresh A1 and B cell suspensions and incubating at 37 °C. The haemolysis was observed macroscopically.
RESULTS: Of 311 donors, 238 (76.5%) showed high anti-A and/or anti-B antibody titres. The highest antibody titre obtained was 256. Female and younger donors (< 40 years old) had higher anti-A and anti-B titres. The anti-B titre showed an association with gender (P < 0.001), and was high in female donors (77.8%). Males aged over 50 years old were found to have low mean titre antibodies. Most donors had both IgM and IgG ABO antibodies. The prevalence of haemolysins in our population was 3.5%.
CONCLUSION: Most of our O blood donors had a high ABO antibody titre but a low prevalence of haemolysins. Males aged over 50 years old are the best O donors for preventing HTRs, particularly when mismatch transfusion is required. We recommend a transfusion unit screen for ABO antibody titre in younger female donors (< 40 years old), to prevent the transfusion of high titre O blood products into non-O recipients.
Fulltext Dual Activity BLEG-1 from Bacillus lehensis G1 Revealed Structural Resemblance to B3 Metallo-β-Lactamase and Glyoxalase II: An Insight into Its Enzyme Promiscuity and Evolutionary Divergence

Au SX, Dzulkifly NS, Muhd Noor ND, Matsumura H, Raja Abdul Rahman RNZ, Normi YM

Int J Mol Sci, 2021 Aug 29;22(17).
PMID: 34502284 DOI: 10.3390/ijms22179377

Metallo-β-lactamases (MBLs) are class B β-lactamases from the metallo-hydrolase-like MBL-fold superfamily which act on a broad range of β-lactam antibiotics. A previous study on BLEG-1 (formerly called Bleg1_2437), a hypothetical protein from Bacillus lehensis G1, revealed sequence similarity and activity to B3 subclass MBLs, despite its evolutionary divergence from these enzymes. Its relatedness to glyoxalase II (GLXII) raises the possibility of its enzymatic promiscuity and unique structural features compared to other MBLs and GLXIIs. This present study highlights that BLEG-1 possessed both MBL and GLXII activities with similar catalytic efficiencies. Its crystal structure revealed highly similar active site configuration to YcbL and GloB GLXIIs from Salmonella enterica, and L1 B3 MBL from Stenotrophomonas maltophilia. However, different from GLXIIs, BLEG-1 has an insertion of an active-site loop, forming a binding cavity similar to B3 MBL at the N-terminal region. We propose that BLEG-1 could possibly have evolved from GLXII and adopted MBL activity through this insertion.
Versatility of subtilisin: A review on structure, characteristics, and applications

Azrin NAM, Ali MSM, Rahman RNZRA, Oslan SN, Noor NDM

Biotechnol Appl Biochem, 2022 Dec;69(6):2599-2616.
PMID: 35019178 DOI: 10.1002/bab.2309

Due to its thermostability and high pH compatibility, subtilisin is most known for its role as an additive for detergents in which it is categorized as a serine protease according to MEROPS database. Subtilisin is typically isolated from various bacterial species of the Bacillus genus such as Bacillus subtilis, B. amyloliquefaciens, B. licheniformis, and various other organisms. It is composed of 268-275 amino acid residues and is initially secreted in the precursor form, preprosubtilisin, which is composed of 29-residues signal peptide, 77-residues propeptide, and 275-residues active subtilisin. Subtilisin is known for the presence of high and low affinity calcium binding sites in its structure. Native subtilisin has general properties of thermostability, tolerance to neutral to high pH, broad specificity, and calcium-dependent stability, which contribute to the versatility of subtilisin applicability. Through protein engineering and immobilization technologies, many variants of subtilisin have been generated, which increase the applicability of subtilisin in various industries including detergent, food processing and packaging, synthesis of inhibitory peptides, therapeutic, and waste management applications.
Fulltext Probing the substrate binding modes and catalytic mechanisms of BLEG-1, a promiscuous B3 metallo-β-lactamase with glyoxalase II properties

Au SX, Mohd Padzil A, Muhd Noor ND, Matsumura H, Raja Abdul Rahman RNZ, Normi YM

PLoS One, 2023;18(9):e0291012.
PMID: 37672512 DOI: 10.1371/journal.pone.0291012

BLEG-1 from Bacillus lehensis G1 is an evolutionary divergent B3 metallo-β-lactamase (MBL) that exhibited both β-lactamase and glyoxalase II (GLXII) activities. Sequence, phylogeny, biochemical and structural relatedness of BLEG-1 to B3 MBL and GLXII suggested BLEG-1 might be an intermediate in the evolutionary path of B3 MBL from GLXII. The unique active site cavity of BLEG-1 that recognizes both β-lactam antibiotics and S-D-lactoylglutathione (SLG) had been postulated as the key factor for its dual activity. In this study, dynamic ensembles of BLEG-1 and its substrate complexes divulged conformational plasticity and binding modes of structurally distinct substrates to the enzyme, providing better insights into its structure-to-function relationship and enzymatic promiscuity. Our results highlight the flexible nature of the active site pocket of BLEG-1, which is governed by concerted loop motions involving loop7+α3+loop8 and loop12 around the catalytic core, thereby moulding the binding pocket and facilitate interactions of BLEG-1 with both ampicillin and SLG. The distribution of (i) predominantly hydrophobic amino acids in the N-terminal domain, and (ii) flexible amino acids with polar and/or charged side chains in both N- and C-termini provide additional advantages to BLEG-1 in confining the aromatic group of ampicillin, and polar groups of SLG, respectively. The importance of these residues for substrates binding was further confirmed by the reduction in MBL and GLXII activities upon alanine substitutions of Ile-10, Phe-57, Arg-94, Leu-95, and Arg-159. Based on molecular dynamics simulation, mutational, and biochemical data presented herein, the catalytic mechanisms of BLEG-1 toward the hydrolysis of β-lactams and SLG were proposed.
Worldwide trend discovery of structural and functional relationship of metallo-β-lactamase for structure-based drug design: A bibliometric evaluation and patent analysis

Azman AA, Leow ATC, Noor NDM, Noor SAM, Latip W, Ali MSM

Int J Biol Macromol, 2024 Jan;256(Pt 2):128230.
PMID: 38013072 DOI: 10.1016/j.ijbiomac.2023.128230

Metallo-β-lactamase (MBL) is an enzyme produced by clinically important bacteria that can inactivate many commonly used antibiotics, making them a significant concern in treating bacterial infections and the risk of having high antibiotic resistance issues among the community. This review presents a bibliometric and patent analysis of MBL worldwide research trend based on the Scopus and World Intellectual Property Organization databases in 2013-2022. Based on the keywords related to MBL in the article title, abstract, and keywords, 592 research articles were retrieved for further analysis using various tools such as Microsoft Excel to determine the frequency analysis, VOSviewer for bibliometric networks visualization, and Harzing's Publish or Perish for citation metrics analysis. Standard bibliometric parameters were analysed to evaluate the field's research trend, such as the growth of publications, topographical distribution, top subject area, most relevant journal, top cited documents, most relevant authors, and keyword trend analysis. Within 10 years, MBL discovery has shown a steady and continuous growth of interest among the community of researchers. United States of America, China, and the United Kingdom are the top 3 countries contribute high productivity to the field. The patent analysis also shows several impactful filed patents, indicating the significance of development research on the structural and functional relationship of MBL for an effective structure-based drug design (SBDD). Developing new MBL inhibitors using SBDD could help address the research gap and provide new successful therapeutic options for treating MBL-producing bacterial infections.
Exploring the Antarctic aminopeptidase P from Pseudomonas sp. strain AMS3 through structural analysis and molecular dynamics simulation

Omar MN, Rahman RNZRA, Noor NDM, Latip W, Knight VF, Ali MSM

J Biomol Struct Dyn, 2024 Mar 31.
PMID: 38555730 DOI: 10.1080/07391102.2024.2331093

Aminopeptidase P (APPro) is a crucial metalloaminopeptidase involved in amino acid cleavage from peptide N-termini, playing essential roles as versatile biocatalysts with applications ranging from pharmaceuticals to industrial processes. Despite acknowledging its potential for catalysis in lower temperatures, detailed molecular basis and biotechnological implications in cold environments are yet to be explored. Therefore, this research aims to investigate the molecular mechanisms underlying the cold-adapted characteristics of APPro from Pseudomonas sp. strain AMS3 (AMS3-APPro) through a detailed analysis of its structure and dynamics. In this study, structure analysis and molecular dynamics (MD) simulation of a predicted model of AMS3-APPro has been performed at different temperatures to assess structural flexibility and thermostability across a temperature range of 0-60 °C over 100 ns. The MD simulation results revealed that the structure were able to remain stable at low temperatures. Increased temperatures present a potential threat to the overall stability of AMS3-APPro by disrupting the intricate hydrogen bond networks crucial for maintaining structural integrity, thereby increasing the likelihood of protein unfolding. While the metal binding site at the catalytic core exhibits resilience at higher temperatures, highlighting its local structural integrity, the overall enzyme structure undergoes fluctuations and potential denaturation. This extensive structural instability surpasses the localized stability observed at the metal binding site. Consequently, these assessments offer in-depth understanding of the cold-adapted characteristics of AMS3-APPro, highlighting its capability to uphold its native conformation and stability in low-temperature environments. In summary, this research provides valuable insights into the cold-adapted features of AMS3-APPro, suggesting its efficient operation in low thermal conditions, particularly relevant for potential biotechnological applications in cold environments.Communicated by Ramaswamy H. Sarma.
Fulltext Acute myocardial infarction as Eosinophilic granulomatosis with polyangiitis (formerly Churg Strauss syndrome) initial presentation. [Infarto agudo do miocárdio como apresentação inicial de granulomatose eosinofílica com poliangiite (anteriormente, síndrome de Churg Strauss)]

Sulaiman W, Ong PS, Mohd Noor S

Rev Bras Reumatol Engl Ed, 2014 Sep-Oct;54(5):393-6.
PMID: 25627304 DOI: 10.1016/j.rbr.2013.03.002

Eosinophilic granulomatosis with polyangiitis is a rare primary vasculitic disease characterized by hypereosinophilia, late onset asthma and extravascular eosinophil granulomas. We report a case presented initially with acute myocardial infarction which later only proceed with asthma, skin manifestations and peripheral neuropathy. Laboratory parameters showed hypereosinohpilia with negative perinuclear pattern of antineutrophil cytoplasmic autoantibodies (p-ANCA). Skin biopsy showed leucocytoclastic vasculitis with eosinophilic infiltration while coronary angiography was normal. The patient's symptoms improved with IV methylprednisolone, pulse cyclophosphamide and azathioprine.
Cruciferous vegetables: dietary phytochemicals for cancer prevention

Abdull Razis AF, Noor NM

Asian Pac J Cancer Prev, 2013;14(3):1565-70.
PMID: 23679237

Relationships between diet and health have attracted attention for centuries; but links between diet and cancer have been a focus only in recent decades. The consumption of diet-containing carcinogens, including polycyclic aromatic hydrocarbons and heterocyclic amines is most closely correlated with increasing cancer risk. Epidemiological evidence strongly suggests that consumption of dietary phytochemicals found in vegetables and fruit can decrease cancer incidence. Among the various vegetables, broccoli and other cruciferous species appear most closely associated with reduced cancer risk in organs such as the colorectum, lung, prostate and breast. The protecting effects against cancer risk have been attributed, at least partly, due to their comparatively high amounts of glucosinolates, which differentiate them from other vegetables. Glucosinolates, a class of sulphur- containing glycosides, present at substantial amounts in cruciferous vegetables, and their breakdown products such as the isothiocyanates, are believed to be responsible for their health benefits. However, the underlying mechanisms responsible for the chemopreventive effect of these compounds are likely to be manifold, possibly concerning very complex interactions, and thus difficult to fully understand. Therefore, this article provides a brief overview about the mechanism of such compounds involved in modulation of carcinogen metabolising enzyme systems.
Fulltext Metabolic profiling of Lactococcus lactis under different culture conditions

Azizan KA, Baharum SN, Mohd Noor N

Molecules, 2012 Jul 03;17(7):8022-36.
PMID: 22759915 DOI: 10.3390/molecules17078022

Gas chromatography mass spectrometry (GC-MS) and headspace gas chromatography mass spectrometry (HS/GC-MS) were used to study metabolites produced by Lactococcus lactis subsp. cremoris MG1363 grown at a temperature of 30 °C with and without agitation at 150 rpm, and at 37 °C without agitation. It was observed that L. lactis produced more organic acids under agitation. Primary alcohols, aldehydes, ketones and polyols were identified as the corresponding trimethylsilyl (TMS) derivatives, whereas amino acids and organic acids, including fatty acids, were detected through methyl chloroformate derivatization. HS analysis indicated that branched-chain methyl aldehydes, including 2-methylbutanal, 3-methylbutanal, and 2-methylpropanal are degdradation products of isoleucine, leucine or valine. Multivariate analysis (MVA) using partial least squares discriminant analysis (PLS-DA) revealed the major differences between treatments were due to changes of amino acids and fermentation products.
Fulltext Development of a voice activity controlled noise canceller

Abid Noor AO, Samad SA, Hussain A

Sensors (Basel), 2012;12(5):6727-45.
PMID: 22778667 DOI: 10.3390/s120506727

In this paper, a variable threshold voice activity detector (VAD) is developed to control the operation of a two-sensor adaptive noise canceller (ANC). The VAD prohibits the reference input of the ANC from containing some strength of actual speech signal during adaptation periods. The novelty of this approach resides in using the residual output from the noise canceller to control the decisions made by the VAD. Thresholds of full-band energy and zero-crossing features are adjusted according to the residual output of the adaptive filter. Performance evaluation of the proposed approach is quoted in terms of signal to noise ratio improvements as well mean square error (MSE) convergence of the ANC. The new approach showed an improved noise cancellation performance when tested under several types of environmental noise. Furthermore, the computational power of the adaptive process is reduced since the output of the adaptive filter is efficiently calculated only during non-speech periods.
Identification of thioketone analogues of sildenfil using gas chromatography-mass spectrometry

Man CN, Noor NM, Lajis R

J Chromatogr A, 2011 Sep 28;1218(39):7055-60.
PMID: 21872876 DOI: 10.1016/j.chroma.2011.08.037

Sildenafil analogues have been found adulterated in herbal preparations and food products that claim to have natural aphrodisiacs. In this study, a gas chromatography-mass spectrometry (GC-MS) assay was developed for the screening and identification of thioketone analogues of sildenafil. Thiopyrazolopyrimidine, a precursor or a cleavage product of thioketone analogue, exhibited characteristic fragment ions of m/z 328 and m/z 299 was found to be the best marker to screen the presence of general thioketone analogues. Identification by GC-MS assay was rapid and specific as all the studied thioketones showed characteristic mass fragmentations including their intact molecular ions. The developed GC-MS assay had successfully identified thiosildenafil, thiohomosildenafil and thiodimethylsildenafil in herbal preparation and food products.
Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production

Sabiha-Hanim S, Noor MA, Rosma A

Bioresour Technol, 2011 Jan;102(2):1234-9.
PMID: 20797853 DOI: 10.1016/j.biortech.2010.08.017

Oil palm (Elaeis guineensis Jacq.) is one of the most important commercial crops for the production of palm oil, which generates 10.88 tons of oil palm fronds per hectare of plantation as a by-product. In this study, oil palm frond fibres were subjected to an autohydrolysis treatment using an autoclave, operated at 121 °C for 20-80 min, to facilitate the separation of hemicelluloses. The hemicellulose-rich solution (autohydrolysate) was subjected to further hydrolysis with 4-16 U of mixed Trichoderma viride endo-(1,4)-β-xylanases (EC 3.2.1.8) per 100 mg of autohydrolysate. Autoclaving of palm fronds at 121°C for 60 min (a severity factor of 2.40) recovered 75% of the solid residue, containing 57.9% cellulose and 18% Klason lignin, and an autohydrolysate containing 14.94% hemicellulose, with a fractionation efficiency of 49.20%. Subsequent enzymatic hydrolysis of the autohydrolysate with 8 U of endoxylanase at 40 °C for 24 h produced a solution containing 17.5% xylooligosaccharides and 25.6% xylose. The results clearly indicate the potential utilization of oil palm frond, an abundantly available lignocellulosic biomass for the production of xylose and xylooligosaccharides which can serve as functional food ingredients.
Blood pressure variability in patients with diabetes mellitus

Mokhtar RH, Ayob A, Mohd Noor N

Asian Cardiovasc Thorac Ann, 2010 Aug;18(4):344-8.
PMID: 20719784 DOI: 10.1177/0218492310375723

Reduced arterial compliance in patients with diabetes mellitus has been shown in several studies, but it has not been significantly associated with either atherosclerosis or vessel wall thickness. Blood pressure variability is still poorly explored in diabetic patients. The aim of this study was to compare blood pressure variability and arterial compliance in patients with type 2 diabetes mellitus and controls matched for sex, age, and weight. Arterial compliance was measured and noninvasive 24-h ambulatory blood pressure monitoring was performed in 18 diabetic patients and 18 controls. There was significantly higher 24-h systolic blood pressure variability (17.7 +/- 6.8 vs. 14.6 +/- 2.6 mm Hg), diastolic blood pressure variability (15.6 +/- 7.1 vs. 11.4 +/- 3.1 mm Hg), and mean arterial blood pressure variability (14.8 +/- 7.0 vs. 11.1 +/- 2.9) in diabetic patients. Systolic, diastolic, and mean arterial blood pressure variability was significantly higher during daytime but not night time in diabetic patients compared to controls. Diabetic patients also had significantly reduced small artery compliance, but no differences in large artery compliance, cardiac output, or systemic vascular resistance. The findings suggest that hyperglycemia may affect the compliance of the vascular system, resulting in high blood pressure fluctuations.
Fulltext Response Ant Colony Optimization of end milling surface roughness

Kadirgama K, Noor MM, Abd Alla AN

Sensors (Basel), 2010;10(3):2054-63.
PMID: 22294914 DOI: 10.3390/s100302054

Metal cutting processes are important due to increased consumer demands for quality metal cutting related products (more precise tolerances and better product surface roughness) that has driven the metal cutting industry to continuously improve quality control of metal cutting processes. This paper presents optimum surface roughness by using milling mould aluminium alloys (AA6061-T6) with Response Ant Colony Optimization (RACO). The approach is based on Response Surface Method (RSM) and Ant Colony Optimization (ACO). The main objectives to find the optimized parameters and the most dominant variables (cutting speed, feedrate, axial depth and radial depth). The first order model indicates that the feedrate is the most significant factor affecting surface roughness.
Physicochemical and functional properties of peeled and unpeeled pumpkin flour

Noor Aziah AA, Komathi CA

J Food Sci, 2009 Sep;74(7):S328-33.
PMID: 19895499 DOI: 10.1111/j.1750-3841.2009.01298.x

This study was intended to investigate the potential of peeled and unpeeled pumpkin pulp as a raw material for the production of flour that could be used in composite blend with wheat flour or as a functional ingredient in food products. The peeled and unpeeled pumpkin pulp were soaked in sodium metabisulphite solution, sliced and dried overnight in a hot air oven, followed by milling into peeled pumpkin pulp flour (PPPF) and unpeeled pumpkin pulp flour (UPPF), respectively. The flours were then evaluated for physicochemical attributes (color, proximate compositions, and water activity) and functional properties (water holding capacity and oil holding capacity), in comparison to the commercial wheat flour. PPPF and UPPF were observed to be more attractive in terms of color than wheat flour, as indicated by the significantly higher results (P or= 0.05) was shown in water holding capacity of PPPF and wheat flour. However, the oil holding capacity of PPPF and UPPF was shown to be significantly higher (P
Naturally-Occurring Glucosinolates, Glucoraphanin and Glucoerucin, are Antagonists to Aryl Hydrocarbon Receptor as Their Chemopreventive Potency

Abdull Razis AF, Noor NM

Asian Pac J Cancer Prev, 2015;16(14):5801-5.
PMID: 26320454

As a cytosolic transcription factor, the aryl hydrocarbon (Ah) receptor is involved in several patho- physiological events leading to immunosuppression and cancer; hence antagonists of the Ah receptor may possess chemoprevention properties. It is known to modulate carcinogen-metabolising enzymes, for instance the CYP1 family of cytochromes P450 and quinone reductase, both important in the biotransformation of many chemical carcinogens via regulating phase I and phase II enzyme systems. Utilising chemically-activated luciferase expression (CALUX) assay it was revealed that intact glucosinolates, glucoraphanin and glucoerucin, isolated from Brassica oleracea L. var. acephala sabellica and Eruca sativa ripe seeds, respectively, are such antagonists. Both glucosinolates were poor ligands for the Ah receptor; however, they effectively antagonised activation of the receptor by the avid ligand benzo[a]pyrene. Indeed, intact glucosinolate glucoraphanin was a more potent antagonist to the receptor than glucoerucin. It can be concluded that both glucosinolates effectively act as antagonists for the Ah receptor, and this may contribute to their established chemoprevention potency.
Thermophysical effects of water driven copper nanoparticles on MHD axisymmetric permeable shrinking sheet: Dual-nature study

Ul Haq R, Rajotia D, Noor NF

Eur Phys J E Soft Matter, 2016 Mar;39(3):33.
PMID: 27006069 DOI: 10.1140/epje/i2016-16033-6

The present study is dedicated to analyze the dual-nature solutions of the axisymmetric flow of a magneto-hydrodynamics (MHD) nanofluid over a permeable shrinking sheet. In those phenomena where the fluid flow is due to the shrinking surface, some reverse behaviors of the flow arise because of vorticity effects. Despite of heat transfer analysis, the main purpose of the present study is to attain the solutions of the complex nature problem that appear in reverse flow phenomena. Thermophysical properties of both base fluid (water) and nanoparticles (copper) are also taken into account. By means of similarity transformation, partial differential equations are converted into a system of coupled nonlinear ordinary differential equations and then solved via the Runge-Kutta method. These results are divided separately into two cases: the first one is the unidirectional shrinking along the surface (m = 1) and the other one is for axisymmetric shrinking phenomena (m = 2) . To enhance the thermal conductivity of base fluid, nanoparticle volume fractions ([Formula: see text]) are incorporated within the base fluid. The numerical investigation explores the condition of existence, non-existence and the duality of similarity solution depends upon the range of suction parameter (S) and Hartmann number (M). The reduced skin friction coefficient and local Nusselt number are plotted to analyze the fluid flow and heat transfer at the surface of the shrinking sheet. Streamlines and isotherms are also plotted against the engineering control parameters to analyze the flow behavior and heat transfer within the whole domain. Throughout this analysis it is found that both nanoparticle volume fraction and Hartmann number are increasing functions of both skin friction coefficient and Nusselt number.

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