Browse publications by year: 2018

  1. Roslinda Shamsudin, Syed Nuzul Fadzli Syed Adam, Azlin Fazlina Osman
    Sains Malaysiana, 2018;47:1303-1310.
    Composite fabricated from the combination of biodegradable polymer and bioactive filler is beneficial for bone tissue
    engineering if the biomaterial can perform similar characteristics of the natural inorganic-organic structures of bone.
    In this study, we have investigated the thermoplastic starch (TPS)/sol-gel derived bioglass composite as new biomaterial
    for bone tissue engineering. The composites were produced using selected TPS/bioglass mass ratio of 100/0, 95/5, 90/10,
    85/15 and 80/20 by a combination of solvent casting and salt leaching techniques. Tensile test results showed the addition
    of bioglass increased the tensile strength and Young’s modulus, but reduced the elongation at break of the samples. The
    modulus of all samples were higher than the requirement for cancellous bone (10-20 MPa). The SEM imaging showed
    the presence of porous structure on the surface of all samples. XRD results confirmed the formation of hydroxycarbonate
    apatite (HCA) layer on the surface of bioglass containing samples; indicating the occurrence of surface reactions when
    the samples were immersed in Simulated Body Fluid (SBF). Furthermore, the presence of P-O stretch band in FTIR
    spectrum between 1000 and 1150 cm-1 and Si-O-Si stretch band at 1000 cm-1 also proved the bioactivity of TPS/bioglass
    composite. The in vitro biodegradability analysis shows the biodegradability of TPS/bioglass composite decreases with
    increasing mass ratio of the bioglass.
  2. Norliza Ismail AJ, Azman Jalar, Maria Abu Bakar, Roslina Ismail
    Sains Malaysiana, 2018;47:1585-1590.
    Kesan tiubnano karbon (CNT) terhadap pertumbuhan lapisan sebatian antara logam (IMC) bagi sistem pateri bebas
    plumbum 96.5Sn-3.0Ag-0.5Cu/substrat Cu telah dikaji. Serbuk aloi Sn-Ag-Cu (SAC305) dicampurkan dengan 0.02 peratus
    berat CNT untuk menghasilkan pes pateri SAC305-CNT. Kedua-dua pes pateri SAC305 dan SAC305-CNT dicetak secara
    manual di atas permukaan papan litar bercetak (PCB) dengan kemasan kuprum (Cu) menggunakan kaedah percetakan
    stensil. Sampel yang telah dicetak dikenakan proses pematerian aliran semula pada suhu 260°C. Sampel yang sudah
    terpateri dikenakan ujian penuaan terma selama 200, 400, 600, 800 dan 1000 jam menggunakan ketuhar penyimpanan
    suhu tinggi (HTS) pada suhu malar iaitu 150°C. Ketebalan lapisan sebatian antara logam (IMC) diukur menggunakan
    alat Pengukuran Fokus Tak Terhingga (IFM®). Keputusan kajian mendapati kadar pertumbuhan lapisan IMC bagi sistem
    SAC305/Cu-CNT adalah 25% lebih rendah berbanding dengan sistem SAC/Cu. Maka, dicadangkan bahawa penambahan
    CNT boleh merencatkan pertumbuhan lapisan IMC sebanyak 25% akibat penuaan terma.
  3. Syed Nuzul Fadzli Syed Adam, Roslinda Shamsudin, Firuz Zainuddin, Mohd Reusmaazran Yusof
    Sains Malaysiana, 2018;47:1293-1302.
    Kajian ini bertujuan untuk mengkaji kesan kandungan fosfat berbeza (X = 10, 15 dan 20% mol) terhadap pembentukan
    morfologi permukaan, ikatan kimia, penghabluran, fasa dan kekuatan mampatan kaca sol-gel tersinter. Serbuk kaca
    gel dengan komposisi 50SiO2
    .(50-X).CaO.XP2
    O5 (dalam peratusan mol) disediakan melalui kaedah sol-gel, dimampat
    membentuk pelet dan disinter pada suhu 1200°C selama 3 jam. Didapati bahawa dengan peningkatan kandungan fosfat,
    mikrostruktur kaca tersinter yang lebih padat terhasil disebabkan peningkatan pemadatan jasad, pengurangan keliangan
    ketara dan pembentukan butiran dan sempadan butiran berhablur yang lebih besar. Peningkatan sebanyak 20% mol
    kandungan fosfat meningkatkan vitrifikasi (fasa kekaca) pada permukaan kaca tersinter yang mana meningkatkan
    pemadatan jasad kepada 83.56%, kekuatan mampatan pada 113 MPa dan penurunan peratusan penghabluran pada
    sekitar 66%. Analisis EDS menunjukkan peningkatan kandungan fosfat menyebabkan peningkatan unsur Si-O pada fasa
    amorfus dan unsur P-O pada fasa berhablur. Analisis FTIR menunjukkan berlaku pemisahan fasa kaya fosfat dan fasa
    kaya silikat dan pada masa sama meningkatkan rangkaian tetrahedra silikat (Si-O-Si) dan fosfat (P-O-P) kaca tersinter.
    Peningkatan kandungan fosfat meningkatkan kumpulan berfungsi berkaitan fosfat hablur dan mengurangkan kumpulan
    berfungsi berkaitan silikat hablur. Ini menyebabkan peningkatan pembentukan fasa silikokarnotit, Ca5 (PO4)2 (SiO4)
    dalam matriks kaca tersinter dengan peningkatan kandungan fosfat yang ditunjukkan melalui analisis XRD.
  4. Muhammad aizat K, Abd shukor R
    Sains Malaysiana, 2018;47:1579-1583.
    Information on semiconductor/superconductor interface is important in fabricating devices of such hybrid systems. In
    this paper the electrical properties and AC susceptibility of Tl2
    Ba2
    CaCu2
    O8
    (Tl-2212) superconductor added with CdTe
    semiconductor are reported. Samples with nominal starting composition Tl2
    Ba2
    CaCu2
    O8
    (CdTe)x with x = 0 to 0.20 weight
    percent (wt. %) have been prepared by the solid-state reaction method. X-ray diffraction patterns showed essentially
    the Tl-2212 phase with presence of impurities (CuO and Tl2
    Ba2
    CuO6
    ) for x ≥ 0.05 wt. % but did not change the Tl-2212
    structure which is tetragonal with lattice parameter a = b ≠ c. The critical onset temperature, Tc-onset for all samples was
    between 104 and 108 K while the critical zero resistance temperature, Tc-zero was from 93 to 95 K. The superconducting
    transition determined by AC susceptibility measurement showed Tcχ’ between 101 and 103 K. The peak temperature, Tp
    of
    the imaginary part of the susceptibility χ” decreased for x = 0.05 and then increased for x > 0.05. This indicated that the
    superconducting grains were strongly coupled for x > 0.05 as a result of CdTe addition. The intergrain critical current
    density, Jc
    at Tp
    for the x = 0.2 sample Jc (Tp
    = 95 K) = 23 A cm-2was the highest among all samples. This sample also
    showed the highest Tp
    indicating CdTe improved the flux pinning of the Tl-2212 phase. This result can be useful in the
    fabrication of semiconductor/superconductor (Tl-2212) hybrid devices.
  5. Samat S, Yasir M, Yusof M, Rosli M
    Sains Malaysiana, 2018;47:1277-1283.
    Bioaccumulation of toxic metals in fish causes serious threats to human when they are consumed. Thus, the detection of
    toxic element concentration levels in aquatic component is important. The accumulation of some heavy metals such as
    Cd, Cu, Fe, Mn, Pb and Zn in fish were determined. Ten species (Selaroides leptolepis, Decapterus maraudsi, Epinephelus
    lanceolatus, Priacanthus tayenus, Rastrelliger, Megalaspis cordyla, Nibea soldado, Pristipomoides filamentosus, Bramidae
    and Siganus canaliculatus) were collected from Terengganu coastal area, Malaysia. The analysis was done using
    inductive coupled plasma-mass spectrometer (ICP-MS) technique. In general, the concentration levels of heavy metals in
    fish samples are lower than the previous study in various locations. The highest average level of heavy metal recorded in
    fish is Fe followed by Zn, Mn, Cu, Cd and Pb. The metal concentration found in this study was lower than the national
    and international recommended dietary allowance (RDA) for human consumption except Fe (52.33 × 10-2 ± 6.39 × 10-2
    mg kg-1) which exceeded the limit of 0.3 mg kg-1. Long term monitoring system of metal bioaccumulation in fishes need
    to be done to provide useful information for the assessment of the potential health risks of metals in Malaysia.
  6. Waqas Ahmad, Muhammad Tahir, Riaz Ahmad, Rashid Ahmad
    Sains Malaysiana, 2018;47:1269-1276.
    Zinc (Zn) deficient soil prevails throughout the world and it has become the bottleneck in achieving production potential
    and quality of crops. The negligible use of micronutrients along with irregular use of macronutrients is practised for
    fodder production in Pakistan. Varying levels of zinc (0, 5, 10 and 15 kg ha-1) and nitrogen (0, 60, 120 and 180 kg ha-1)
    were evaluated for their effect on yield, quality and zinc uptake on fodder sorghum (variety Hegari) in a field experiment
    for two consecutive years (2014 and 2015). Data were analysed by using Fishers’ analysis of variance (at p<0.05) and
    response surface methodology (RSM). Correlation between different parameters was also studied. Application of zinc
    and nitrogen improved the plant height, leaf area plant-1, green fodder yield, dry matter yield, crude protein percentage
    and zinc content of plant but decreased the neutral detergent fiber, acid detergent fiber and ash percentage. Values for
    different parameters recorded at second and third levels of zinc and nitrogen were remained at par with each other.
    Application of 10 kg ha-1 zinc and 120 kg ha-1 nitrogen showed an average increase of 7.3 and 18.6% in green fodder
    yield while 12.1 and 15.8% in dry matter yield, respectively. Similarly 6.1 and 7.5% increase in crude protein was noted
    over control. Correlation between NDF and ADF was negative with rest of the studied parameters. In conclusion, Zn2
    and
    N2
    gave the best results in term of yield and quality of fodder sorghum.
  7. Noradira Suhaime, Masniza Sairi, Nur Biha Mohamed Nafis, Suriati Paiman, Tity Nazleen Mohamed, Zulkifly Abbas, et al.
    Sains Malaysiana, 2018;47:1571-1578.
    The maturity of mango is usually assessed by the determination of its moisture content (m.c.), soluble solid content (SSC)
    and pH. However, these techniques are either time consuming, tedious or destructive. In this research, we extend the
    application of the open-ended coaxial probe technique to determine m.c. and pH of Chok Anan mango from its dielectric
    properties from week 5 to week 17 after anthesis. The effects of frequency and m.c. on the values of the dielectric constant
    and loss factor were also investigated. The critical frequency separating the different polarizations was found to be
    inversely proportional to m.c. Also, in this research we proposed a new classification of fruit ripeness related to the number
    of weeks after anthesis. The actual dielectric properties, m.c., SSC and pH of Chok Anan mango were measured using
    standard methods. Relationships were established between the dielectric constant, loss factor, critical frequency, pH and
    m.c. The accuracy for the determination of m.c. and pH using the coaxial probe was within 1.7% and 3.0%, respectively.
    MeSH terms: Choline Kinase; Fruit; Mangifera; Imidazolidines
  8. Rosmawati Dora, Hasnah Haron, Muhamad Fikri Mohd Fauzi, Suzana Shahar, Chong CP, Mohd Fairulnizal Md Noh
    Sains Malaysiana, 2018;47:1557-1562.
    This study was conducted to determine the content of macronutrients and sugar in 30 types of food selected from three
    zones in Peninsular Malaysia. The food samples consisted of 14 types of processed foods and beverages, 8 types of
    fruits and 10 types ready to eat food. Each type of food and drink were purchased from selected restaurants, stores and
    supermarkets from three different zones which were North zone (Perak), Central zone (Selangor) and South Zone (Johor).
    Methods used for proximate analysis were based on the standard methods of AOAC (1997) while the total carbohydrate
    was calculated by difference method. Total calories were calculated using Atwater method. Total sugar content were
    analysed using high performace liquid chromatography (HPLC). Dietary fibre contents were determined by using a
    combination of enzyme-gravimetric methods (AOAC 985.29 and AACC 32-05). The results showed that peanut butter has
    the highest value of fat (44.75 ± 7.59 g/100 g), total calorie (611 ± 38 kcal /100 g) and dietary fibre contents (8.07 ± 0.98
    g/100 g). Highest protein content (21.98 ± 2.57 g/100 g) was found in low-fat milk powder. The highest carbohydrate
    (97.48 ± 1.47 g/100 g) and total sugar (86.7 ± 2.9 g/100 g) contents were found in palm sugar. The results of this study
    will update and add up to the data for the Malaysian Food Composition Table and can provide useful information in
    choosing healthy foods based on the nutrient contents of the food.
  9. Marhaini Mostapha, Noorhasmiera Abu Jahar, Sarani Zakaria, Sharifah Nabihah Syed Jaafar, Kamalrul Azlan Azizan, Wan Mohd Aizat
    Sains Malaysiana, 2018;47:1259-1268.
    Oil palm is the major crop grown and cultivated in various Asian countries such as Malaysia, Indonesia and Thailand.
    The core of oil palm trunk (COPT) consists of high sugar content, hence suitable for synthesis of fine chemicals and
    biofuels. Increase of sugar content was reported previously during prolonged COPT storage. However, until now, there
    has been no report on protein profiles during storage. Therefore, in this study, protein expression of the COPT during the
    storage period of one to six weeks was investigated using sodium dodecyl sulphate polyacrylamide gel electrophoresis
    (SDS-PAGE) coupled with optical density quantification and multivariate analyses for measuring differentially expressed
    proteins. Accordingly, protein bands were subjected to tryptic digestion followed by tandem mass spectrometry (nanoLCMS/MS)
    protein identification. The results from SDS-PAGE showed consistent protein bands appearing across the biological
    replicates ranging from 10.455 to 202.92 kDa molecular weight (MW) regions. The findings from the principal component
    analysis (PCA) plot illustrated the separation pattern of the proteins at weeks 4 and 5 of storage, which was influenced
    mainly by the molecular weights of 14.283, 25.543, 29.757, 30.549, 31.511, 34.585 and 84.395 kDa, respectively. The
    majority of these proteins are identified as those involved in stress- and defense-related, disease resistance, as well
    as gene/protein expression processes. Indeed, these proteins were mostly upregulated during the later storage period
    suggesting that long-term storage may influence the molecular regulation of COPT sap.
    MeSH terms: Electrophoresis, Polyacrylamide Gel; Indonesia; Malaysia; Molecular Weight; Proteins; Sodium Dodecyl Sulfate; Thailand; Transcriptional Activation; Up-Regulation; Multivariate Analysis; Proteomics; Tandem Mass Spectrometry; Biofuels; Disease Resistance
  10. Siti Zubaidah Hasan, Zuhailie Zakaria, Mohamed Rozali Othman, Muhammad Rahimi Yusop
    Sains Malaysiana, 2018;47:1547-1556.
    Mangan oksida (MnO2
    ) poros nano yang mempunyai morfologi lapisan nipis telah disintesis dan diaplikasikan sebagai
    penjerap pewarna sintetik komersial (remazol merah, eriokrom hitam dan metilena biru). Permukaan bahan silika
    alumina yang telah diubah suai dengan 3-aminopropiltrietoksisilana (APTES) digunakan dalam proses sonokimia pada
    suhu bilik dengan kehadiran 0.1 M kalium permanganat (KMnO4
    ) untuk menghasilkan komposit silika alumina-MnO2
    .
    Penyingkiran templat dijalankan untuk mendapatkan MnO2
    tulen bersaiz nano. Spektrum FTIR menunjukkan kehadiran
    getaran MnO2
    dalam julat 400 - 600 cm-1 dan corak XRD menunjukkan kehadiran birnesit jenis MnO2
    . Isoterma jerapnyahjerap
    N2
    menunjukkan MnO2
    tulen memiliki liang yang bersifat mesoporos iaitu 34.8 Å (± 0.4), manakala luas
    permukaan MnO2
    ialah 252.8 m2
    /g. Penjerap MnO2
    lapisan nipis yang diperoleh menunjukkan kebolehan menjerap
    pewarna eriokrom hitam dan metilena biru masing-masingnya sehingga 54% dan 99% serta kapasiti penjerapan masingmasing
    ialah 0.0024 dan 0.0077 mmol/g. Kedua-dua isoterma penjerapan eriokrom hitam dan metilena biru oleh MnO2
    masing-masing menepati ciri-ciri Langmuir dan Temkin. Sementara itu data kinetik penjerapan eriokrom hitam dan
    metilena biru kedua-duanya memenuhi tertib pertama pseudo.
  11. Azman Jalar, Norinsan Kamil Othman, Emee Marina Salleh, Zaifol Samsu
    Sains Malaysiana, 2018;47:1251-1257.
    Keluli karbon amat mudah terkakis dalam pelbagai persekitaran terutamanya dalam keadaan berudara lembap dan suhu tinggi. Oleh sebab itu, permukaan keluli karbon perlu dilindungi dengan bahan atau logam yang mampu menangani serangan kakisan yang agresif dengan membentuk lapisan oksida dan lapisan antara logam yang bersifat pelindung. Kajian ini dijalankan untuk menentukan mikrostruktur permukaan dan kekerasan salutan aluminium (Al) tulen yang telah dihasilkan melalui teknik celupan panas. Celupan panas dalam leburan Al tulen dilakukan pada suhu berbeza untuk mendapatkan lapisan salutan yang optimum. Keputusan teknik celupan panas menunjukkan dua lapisan utama terhasil iaitu lapisan luar Al dan lapisan dalam aluminit (Fe-Al). Manakala lapisan dalam aluminida terdiri daripada dua lapisan yang berbeza iaitu lapisan nipis luar FeAl3 dan lapisan tebal dalam Fe2Al5. Keputusan daripada ujian mikrokekerasan Vickers menunjukkan bahawa nilai kekerasan lapisan aluminida meningkat dengan peningkatan suhu leburan Al manakala lapisan Al tidak menunjukkan sebarang perubahan yang ketara.
    MeSH terms: Aluminum; Diabetic Neuropathies; Naltrexone; Fenofibrate
  12. Naili Nahar, Nor Ainy Mahyudin
    Sains Malaysiana, 2018;47:1541-1545.
    Food borne diseases increase worldwide and contamination of food contact surfaces serves as one of the reasons for their occurrence. The aim of this study was to determine the microbiological quality of spoons at selected restaurants in Klang Valley, Malaysia. Five restaurants were selected therein for the study. They were respectively labelled A, B, C, D and E. A total of 150 cleaned spoons (30 spoons from each restaurants) that were ready to be used by customers at the restaurants were examined. Total plate counts (CFU/cm2) of the spoons were determined; the presumptive and confirmatory tests for the presence of Escherichia coli on the spoons were also conducted. The samples were collected by surface swabbing. The result showed that restaurant C and B had the highest and lowest total plate counts (TPC), respectively. Samples from 3 of the 5 selected restaurants (restaurants C, D and E) showed positive results for the presence of E. coli mainly due to poor dishware cleansing. On the contrary, negative results for the presence of E. coli at restaurant A and B were associated with the advance cleaning procedure, which used more hygienic method with dishwashers.
    MeSH terms: Escherichia coli; Food; Foodborne Diseases; Hygiene; Malaysia; Restaurants
  13. Israa Abdulqasim Mohammed Ali, Zamri Zainal Abidin, Chorng-Yuan Hwang, Adele Laurie Plunkett
    Sains Malaysiana, 2018;47:1241-1249.
    We investigated the central mass distribution of the luminous infrared galaxy NGC 3256 at a distance of 35 Mpc by using
    CO(1-0) observations of the Atacama Large Millimeter and sub-millimeter Array (ALMA) and near-IR data of the Two
    Micron Sky Survey (2MASS). We found that there is a huge amount of invisible dynamical mass (4.48 × 1010 ) in the
    central region of the galaxy. The invisible mass is likely caused by some dark matter, which might have a cuspy dark
    matter profile. We note that this dark matter is difficult to explain with the conventional Modified Newtonian Dynamics
    (MOND) model, which is only applicable at a low acceleration regime, whereas the acceleration at the central region
    of the galaxy is relatively strong. Therefore, this discovery might pose a challenge to the conventional MOND models.
  14. Safiyyah Shahimi, Wan Sakeenah Wan Nazri, Aminah Abdullah, Norrakiah Abdullah Sani, Sahilah Abd. Mutalib
    Sains Malaysiana, 2018;47:1535-1540.
    Genomic DNA of 13 fish (n=13) species consist of four freshwater which were catfish (Clarias gariepinus), shark catfish (Pangasius larnaudii), tilapia (Oreochromis mossambicus), perch (Lates calcarifer) and nine marine species which were black pomfret (Parastromateus niger), anchovy (Stolephorus commersonii), mabong (Rastrelliger kanagurta), red snapper (Lutjanus erythropterus), herring (Chirocentrus dorab), ray fish (Himantura gerrardii), sardine (Decapterus macrosoma), mackerel (Euthynnus affinis) and tuna (Thunnus tuna) were differentiated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Seven endonucleases of AluI, BsaJI, HaeIII, HindIII, HinfI, MboI and MboII were examined for the ability to digest cyt b amplicon from each species. Genomic DNA of pork (Sus scrofa domestica) were differentiated from fishes by comparing the digestion patterns produced by similar amplified region and enzymes used. In the present study, it was demonstrated that fishes and pork DNA genome were successfully differentiated using all endonucleases except for HindIII. Thus, PCR-RFLP analysis was found useful for future pork DNA detection in fish products.
    MeSH terms: Red Meat; Animals; Catfishes; DNA; Endonucleases; Fish Products; Fresh Water; Niger; Perches; Polymorphism, Restriction Fragment Length; Sharks; Swine; Tuna; Polymerase Chain Reaction; Tilapia; Seafood; Genomics; Sus scrofa; Cytochromes b
  15. Liyana Mohd Ali Napia, Faizal Mohamed, Hur Munawar Kabir Mohd, Intan Syakeela Ahmad Bastamam, Shamellia Sharin, Norsyahidah Mohd Hidzir, et al.
    Sains Malaysiana, 2018;47:1235-1240.
    Unilamellar liposomes composed of dipalmitoylphosphatidylcholine (DPPC) were prepared by the reverse-phase
    evaporation method and extrusion through a polycarbonate membrane filter. Liposomes at 0.7 mg/mL lipid concentration
    in deionized water were exposed to gamma irradiation at a dose in the range 0.5 to 25 kGy. Gamma irradiation of
    liposomes resulted in the degradation of DPPC lipids into free fatty acids, lysophosphatidylcholine and 1,2-palmitoylphosphatidic
    acid (DPPA). The effect of gamma irradiation towards the physical stability of liposomes was investigated
    by means of dynamic light scattering (DLS), transmission electron microscopy (TEM) and zeta potential analysis. From
    the DLS analysis, no significant changes were observed in the hydrodynamic size of liposomes. TEM images indicate that
    the liposomes surface became smoother and rounder as higher irradiation doses were applied. Zeta potential analysis
    showed that gamma irradiation of DPPC liposomes at radiation doses as low as 0.5 kGy resulted in a drastic rise in the
    magnitude of the zeta potential. The results also demonstrate that gamma irradiation of liposomes suspension enhanced
    the overall stability of liposomes. Hence, it can be concluded that gamma irradiation on DPPC liposomes may potentially
    produce liposomes with higher stability.
    MeSH terms: Dynamic Light Scattering; Fatty Acids, Nonesterified; Lysophosphatidylcholines; Polycarboxylate Cement; Radiation Dosage; Suspensions; Water; 1,2-Dipalmitoylphosphatidylcholine; Microscopy, Electron, Transmission; Unilamellar Liposomes; Hydrodynamics
  16. Siti Nurul Ain Saipullizan, Razalee Sedek, Sahilah Abd. Mutalib
    Sains Malaysiana, 2018;47:1527-1533.
    This study aimed to evaluate the level of knowledge, attitude and practice (KAP) amongst food handlers in food utensils
    hygiene and presence of bacterial contamination on food utensils. There were two approaches used in this study. In the
    first approach, 134 of food handlers from 75 food premises were interviewed via questionnaires to assess their knowledge,
    attitude and practice. In the second approach, the presence of Staphylococcus aureus, Escherichia coli and total coliform
    of 225 utensils (knives (75), chopping boards (75) and dish plates (75)) was examined. The result showed that the food
    handlers had sufficient level of knowledge (80.5%), attitude (87.4%) and practice (90.1%). Highest contamination was
    found on the chopping boards for the presence of S. aureus (82.8%), E. coli (9.7%) and total coliform (73.9%). Logistic
    regression analysis showed that knowledge contributes to the presence of E. coli on the dish plates; and total coliform
    on the knives. Thus, ongoing training that focused on food utensils hygiene must be emphasized to improve knowledge,
    attitude and practice amongst the food handlers.
    MeSH terms: Escherichia coli; Food Handling; Hygiene; Surveys and Questionnaires; Regression Analysis; Staphylococcal Infections; Staphylococcus aureus
  17. Malina Jasamai, Nurul Hanis Samsudin, Norazrina Azmi, Endang Kumolosasi
    Sains Malaysiana, 2018;47:1221-1226.
    Durian or scientifically known as Durio zibethinus is one of the most well-known seasonal fruits in the Southeast Asia
    region. However, its safe consumption in individuals with hypertension is still controversial. This study was conducted
    to investigate the effect of durian on blood pressure of spontaneously hypertensive rat model. Four groups of rats (n=5)
    were fed with either a low dose durian (26 g/kg), a high dose durian (52 g/kg), sugar solution (8 mL/kg) which has
    similar sugar composition in the durian as placebo control, and distilled water as vehicle control (8 mL/kg) for 14 days.
    The durian doses for rats were obtained by converting from human doses. Baseline reading of blood pressure and heart
    rate were recorded before the first oral administration of durian. The blood pressure and heart rate were also measured
    1 h after the durian oral administration on day 1, 3, 7 and 14 of the experiment. In conclusion, durian fruit possessed
    an acute effect on the blood pressure of hypertensive rats but heart rate was unaffected. High dose administration of
    durian led to significant elevation of blood pressure after 1 h of consumption. Meanwhile, low dose of durian (26 g/kg)
    caused an insignificant reduction in systolic and diastolic blood pressure. Tolerance to the durian fruit was observed after
    three to seven days of the oral administration and low dose consumption of durian fruit was safe in the hypertensive rat.
    MeSH terms: Administration, Oral; Animals; Asia, Southeastern; Blood Pressure; Blood Pressure Determination; Fruit; Heart; Heart Rate; Humans; Hypertension; Rats, Inbred SHR; Reading; Seasons; Systole; Bombacaceae; Rats
  18. Aina Aqila Arman Alim, Rizafizah Othaman
    Sains Malaysiana, 2018;47:1517-1525.
    Epoxidized natural rubber/polyvinyl chloride/microcrystalline cellulose (ENR/PVC/MCC) composite membranes were
    prepared and used to treat palm oil mill effluent (POME). The loadings of MCC were varied at 0, 5, 10 and 15 w/w%. The
    increment of MCC loads has intensified the hydroxyl peak of the membranes in FTIR spectrum, indicating the increase
    in membrane hydrophilicity. MCC acted as a pore forming agent since the ENR/PVC/10% MCC gave the highest water
    flux and well-distributed pores. After first treatment of POME, the levels of chemical oxygen demand (COD), biochemical
    oxygen demand (BOD) and total suspended solid (TSS) were reduced to 99.9%, 70.3%, and 16.9%, respectively. These
    data showed that ENR/PVC/MCC membrane has the potential to treat POME.
    MeSH terms: Cellulose; Membranes; Oxygen; Polyvinyl Chloride; Rubber; Water; Spectroscopy, Fourier Transform Infrared; Hydroxyl Radical; Biological Oxygen Demand Analysis; Hydrophobic and Hydrophilic Interactions
  19. Wun FML, Chong YY, Law KP, Ishak Ahmad, Mohammad Kassim
    Sains Malaysiana, 2018;47:1491-1499.
    The Re(I) complex, [Re(PyPzH)(CO)3
    Cl] where PyPzH = 2-(1H-pyrazol-3-yl)pyridine, was successfully synthesised
    and characterised with an infrared (IR), ultraviolet-visible (UV-Vis), 1
    H and 13C nuclear magnetic resonance (NMR)
    spectroscopies and X-ray crystallography. The IR spectrum featured three n(C≡O), n(N-H), n(C=N) and n(C=C) signals
    at (1860-2020), 3137, 1614 and 1513 cm-1, respectively. The UV-Vis spectrum of the complex exhibited ligand-centred
    (π®>*) electronic excitations [λmax = 227 nm, ε = 1.942 x 104 M-1cm-1; lmax = 292 nm, ε = 0.853 x 104 M-1cm-1] and
    a metal-to-ligand charge transfer (MLCT) band [lmax = 331 nm, ε = 0.467 x 104 M-1cm-1]. The 13C and 1
    H-NMR spectra
    exhibited the characteristic signals of the three C≡O (189.0 – 199.0 ppm) and NH (14.84 ppm), respectively. The X-ray
    structure of [Re(PyPzH)(CO)3
    Cl] showed the crystal adopted a monoclinic system with a C2/c space group [unit cell
    dimensions: a = 27.7422(14) Å, b = 11.1456(5) Å, c = 9.2461(4) Å with α = γ = 90º and β = 92.552(2)º]. Density
    functional theory (DFT) and time-dependent (TD) DFT calculations were performed to investigate the optimised structural
    geometry and electronic properties of the title complex. The results showed that the highest-occupied molecular orbital
    (HOMO) was predominantly found on the dπ-orbitals of Re(I), Cl and CO. While the lowest-unoccupied molecular orbital
    (LUMO) was located on the PyPzH moiety. The structural and photophysical properties of the [Re(PyPzH)(CO)3
    Cl] were
    established and the reaction enthalpies for the dissociation of Cl atom in the formation of [Re(PyPzH)(CO)3
    ]•
    were
    discussed in view of its potential application for photocatalytic CO2
    reduction.
  20. Imran Fakhar, Bohari Muhammad Yamin, Sahilah Abdul Mutalib, Siti Aishah Hasbullah
    Sains Malaysiana, 2018;47:1199-1208.
    The two new symmetrical bis-thiourea compounds, 2,2’-[{(terephthaloylbis(azanediyl)bis (carbonothioyl)bis(azanediyl)}
    bis(4-methylpentanoicacid)] 1A and 2,2’-[{(isophthaloylbis (azanediyl)bis(carbonothioyl)bis(azanediyl)}bis(4-
    methylpentanoic acid)] 1B have been synthesized by reacting terephthaloyl/isophthaloyl chloride and L-leucine in high
    yields. Newly synthesized bis-thiourea derivatives were characterized using FTIR, 1D NMR, 2D NMR, MS spectrometry and
    Elemental analysis. Their binding properties with various cations were also carried out using UV-vis titration experiments.
    Both isomers exhibited effective binding against Ag+, Cu2+, Ni2+, Hg2+, Pb2+, Fe2+, and Fe3+ in the presence of other cations,
    such as Na+, Co2+, Cd2+, Zn2+, Mn2+, Mg2+, Ca2+, Sn2+, and Al3+. Stoichiometries of the host-guest complexation for both
    isomers were found to be 1:4 by plotting molar-ratio curves. Pearson Product moment correlation coefficient was in the
    range of 0.83-0.99 and nonlinear regression equation was used to calculate dissociation constant (Kd
    ). Both compounds
    displayed weak antibacterial activities against gram-positive and gram negative bacteria. Cytotoxicity testing on CCD841
    Normal human colon epithelial cell line showed that both compounds are non-toxic, with an IC50 value of 1.50 mg/mL.
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