Malaysian Journal of Science https://mjs.um.edu.my/index.php/MJS <p style="text-align: justify;">Malaysian Journal of Science (MJS), launched in 1972, is the official peer-reviewed open access journal of the&nbsp;<a href="https://fs.um.edu.my/">Faculty of Science, University of Malaya</a>.&nbsp;Effective from&nbsp;year 2020 onwards, the frequency of regular issues publication is&nbsp;three&nbsp;times a&nbsp;year; on&nbsp;every February, June and October. MJS is indexed in Scopus, EMBASE, Compendex, GEOBASE, EMBiology, Elsevier BIOBASE, FLUIDEX ,World Textiles, CAB Abstracts, Chemical Abstracts Service Database and ASEAN Citation Index (ACI).</p> <p style="text-align: justify;">MJS is a reputable journal with a growing number of audience, which focuses on current developments in all disciplines of science. The journal publishes original articles, review articles, short communications and case reports that are of importance to the scientific community.&nbsp;</p> <p style="text-align: justify;"><strong>eISSN&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;: 2600-8688<br></strong><strong><strong>Print ISSN&nbsp; &nbsp;: 1394-3065<br></strong></strong><strong><strong>Publisher&nbsp; &nbsp; : Faculty of Science, University of Malaya</strong></strong>&nbsp;</p> Faculty of Science, University of Malaya en-US Malaysian Journal of Science 1394-3065 <p><img src="/public/site/images/mjs_um/Copyright_Agreement_OJS_-_adjust-page-001.jpg" alt="" width="958" height="1240"></p> PAVO CRISTATUS FEATHER POWDER AS AN ECO-FRIENDLY AND LOW COST MATERIAL FOR MITIGATION OF Pb(II) IONS FROM WATER https://mjs.um.edu.my/index.php/MJS/article/view/17467 <p>Mitigation of Pb(II) ions from water&nbsp; using economic method is an important research area to combat the pollution due to lead ions Pb(II) &nbsp;in <strong>water as it&nbsp; </strong>have severe toxic effects in human beings. In present work, Pristine <em>Pavo Cristatus </em>feather powder (PCFP) has been employed for removal of Pb(II) ions and the process of adsorption was optimized through four level Box Behnken design (BBD) of response surface methodology (RSM) over a broad range of pH (3.0–9.0), initial lead ion concentration (20–100 mg/L), contact time (20–180 min) and temperature (297 K to 333 K). <em>Different isotherms were applied to confirm the type of adsorption. </em>Langmuir maximum removal efficiency was 121.95 mg/g for lead ions adsorption onto PCPF at optimal values of pH 6; adsorbent dose 20 mg/L; temperature 303 K and contact time 120 minutes obtained from batch studies. Pseudo-second-order reaction model showed good applicability for kinetic studies.<em> Thermodynamic parameters were also evaluated to check feasibility and nature of adsorption</em>. The optimal parameters obtained for maximum Pb(II) ions adsorption were at pH = 6.31,&nbsp; initial Pb(II) ion&nbsp; = 43.79 mg/L, contact time = 119.51 minutes and temperature = 59.67 <sup>o</sup>C. The experimental and predicted values were found to be in good agreement with each other.</p> Suman Saini Jyoti Chawla Rajeev Kumar Inderpreet Kaur Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 1 21 10.22452/mjs.vol40no1.1 STERILIZABLE MINIATURE BIOREACTOR PLATFORM FOR ANAEROBIC FERMENTATION PROCESS https://mjs.um.edu.my/index.php/MJS/article/view/19727 <p>This paper presents the establishment of a miniature bioreactor platform for anaerobic microbial fermentation processes. It is made from a universal glass bottle and has a working volume of 16 mL. Reactor features included mixing via magnetic stirrer, temperature control via electrical heater and cells optical density (OD) sensing. All sensors and actuators integrated into the reactor were operated using LabVIEW<sup>TM</sup> (National Instrument, TX, US). The top lid of the bottle was modified to include a 3mm poly(methylmethacrylate) (PMMA) polymer layer where it was machined to provide spaces for fluidic ports and integration of sensors. Each reactor components were sterilized prior to conducting fermentation experiments. Main body of the reactor was made of glass and it was sterilized using the standard heat sterilization method (121<sup>o</sup>C for 15 minutes) where else other components were sterilized by exposure to UV light for 2 hours. A series of anaerobic fermentation experiments were conducted in batch mode using <em>S.cerevisiae</em> to evaluate the workability of the system. Fermentation experiments were conducted using inoculum concentration of 2 g∙L<sup>-1</sup> and starting glucose concentration between 10 g∙L<sup>-1</sup> and 20 g∙L<sup>-1</sup>. In every experiment, mixing was set to operate at 400 rpm and temperature was adjusted to 30 ± 2<sup>o</sup>C. Experiments were carried out until stationary phase was attained. Under these conditions, the best fermentation profile was obtained with glucose concentration of 20 /L where cell specific growth rate was found to be about 0.28 h<sup>-1</sup>. Bench marking step was also performed where results attained in a miniature bioreactor platform were comparable with the one attained using a 50 mL flask.</p> Zainuddin Arriafdi Arvind Ramachendrin Muhd Nazrul Hisham Zainal Alam Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 22 33 10.22452/https://doi.org/10.22452/mjs.vol40no1.2 NOVEL MUTATIONS OF THE G6PC GENE IN MALAYSIANS WITH GLYCOGEN STORAGE DISEASE 1a (GSD1a) https://mjs.um.edu.my/index.php/MJS/article/view/22078 <p><strong>Abstract</strong></p> <p>Glycogen Storage Disease 1a is a rare autosomal recessive disorder caused by mutations in the glucose-6-phosphatase gene (<em>G6PC</em>) encoding glucose-6-phosphatase (G6Pase), a key enzyme for the maintenance of glucose homeostasis. Deficiency of G6Pase underlies this disease associated with life-threatening hypoglycemia and growth retardation. To date, more than 110 mutations have be found worldwide.The aims of this study are to identify the mutations in <em>G6PC</em> gene in Malaysian GSD1a patients using standard molecular genetics methods and to determine the pathogenicity level of the novel mutations. We performed mutation screening for 21 GSD1a unrelated patients (Malay n=14; Chinese n=7) using Polymerase Chain Reaction (PCR) and DNA sequencing. Genomic DNA was extracted from patients’ peripheral blood and all five <em>G6PC</em> exons were amplified using specific primers. Nine mutations were found, in which five mutations have been previously reported and four are potentially novel mutations (H52L, K76X, P113S and A346P). To obtain further evidence on the potential pathogenicity of the novel mutations, restriction enzyme assay and TaqMan genotyping assay were designed to investigate its allele frequency in a panel of healthy individuals that serves as the control population samples (n=50 Malays, n=50 Chinese, n=50 Indians). Restriction enzymes <em>Mse</em>I and <em>Mbo</em>I were used to assay the K76X and P113S mutations respectively. For the other two mutations (H52L and A346P), TaqMan genotyping assays was employed due to inavailability of a suitable restriction enzyme to distinguish between the normal and mutant sequences. Results obtained from both the restriction enzymes assays and the TaqMan assays showed that no mutant allele could be found in all 150 healthy individuals (300 alleles). In conclusion, four yet unreported mutations have been found in the Malaysian population, and these mutations are potentially novel pathogenic mutations. These finding provide support that the mutations spectrum of <em>G6PC</em> gene in Malaysia is heterogeneous, at least among the Chinese and Malay populations.</p> <p>KEY WORDS: Glycogen storage disease type 1a (GSD1a); glucose-6-phosphatase enzyme (G6Pase); Glucose-6-Phosphate catalytic subunit (<em>G6PC</em>).</p> Amirah Assyiqqin Abd Rahman Ili Syazwana Abdullah Teh Ser Huy Fiqri Dizar Khaidizar Sufin Yap Keng Wee Teik Ngu Lock Hock Chew Hui Bein Ong Pei Tee Zulqarnain Mohamed Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 34 45 10.22452/mjs.vol40no1.3 SUITABILITY OF BI-VACANCY TRAP FOR TL EMISSION IN KCl https://mjs.um.edu.my/index.php/MJS/article/view/24651 <p>In KCl crystals, the 2s energy level of F-center within an anion-cation vacancy pair has been proposed as a suitable trap for thermoluminescence (TL) emission. It is further seen that the 2s – level of F-center situated in cation – anion vacancy pair has large trap depth. The observed trap depth of F-center is explainable on the basis of Herman and Barnett model, modified presently and supports bi-vacancy configuration for traps in KCl lattice.</p> Ruchi Pandey Shankar Datt Pandey Sumit Kumar Rajendra Kumar Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 46 54 10.22452/mjs.vol40no1.4 SIZE REDUCTION OF KLOPFENSTEIN-BALUN TRANSFORMER FOR BALANCED ANTENNAS https://mjs.um.edu.my/index.php/MJS/article/view/13584 <p class="Abstract" style="margin-top: 0in; text-indent: 0in;"><span style="font-size: 12.0pt;">A BALUN transformer converts impedance into another one and also converts an unbalanced line into a balanced line. A compact size broadband BALUN transformer is designed using Klopfenstein taper line transformer approach to transform 50Ω impedance into 100 Ω. The results of the conventional BALUN are compared with the proposed compact size BALUN. In order to reduce the length of the BALUN, a curved microstrip line is used. The proposed compact size BALUN is 56 %- 70 % smaller in size w.r.t the conventional BALUN but at the cost of 6% - 11% reduction in the overall band. The conventional BALUN has measured % bandwidth of 165 while the reduced size BALUN has 159. The measured results are in agreement with the simulated results. </span></p> Shailendra P. Shastri Ravish R. Singh Sandeep Y. Pawar Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 55 66 10.22452/mjs.vol40no1.5 SUNLIGHT DRIVEN PHOTOCATALYTIC DEGRADATION OF 2-CHLOROPHENOL BY POLYPYRROLE/GRAPHENE OXIDE COMPOSITES https://mjs.um.edu.my/index.php/MJS/article/view/24456 <p>Polypyrrole/graphene oxide (PPy/GO) was synthesized and evaluated as an effective photocatalyst to degrade 2-chlorophenol from aqueous solution under solar light irradiation. The PPy/GO composite was synthesized by the incorporation of PPy with the GO using Hummer’s method(s). Three different compositions of PPy/GO composites were prepared with the varying ratio of PPy and GO (1:1, 1:4, 9:1). Physicochemical properties of pristine PPy, GO and as synthesized PPy/GO composites were characterized using FTIR, UV-Vis, XRD, and SEM with EDX. The characterizations results revealed that PPy was successfully integrated with the GO in the PPy/GO composites. The photodegradation of 10 ppm of 2-chlorophenol has been observed under sunlight for 3 hours with the exposure contact time of 180 minutes before being tested with UV-Vis in order to obtain the percentage of degradation in the sunlight. The degradation study exhibited that PPy/GO composite with the ratio of 1:1 exhibited the highest percentage of degradation of ~ 71.08 and 68.96 % at the time of 180 minutes and 3 hours respectively.</p> Siti Nor Atika Baharin Kavirajaa Pandian Sambasevam Nur Farahin Suhaimi Arifutzzaman Rahat Saidur Rahman Shafira Nadira Musiran Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 67 79 10.22452/mjs.vol40no1.6 A SENSITIVE SPECTROPHOTOMETRIC METHOD FOR TRACE AMOUNTS DETERMINATION OF PROMETHAZINE IN DRUG FORMULATIONS VIA ION PAIR COMPLEX FORMATION https://mjs.um.edu.my/index.php/MJS/article/view/23935 <p><strong>ABSTRACT&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;</strong>This paper discusses a quick and easy spectrophotometric approach for the estimation of promethazine HCl drug in a pure and pharmaceutical formulation. This system relies on the instruction of colour ion-pair between complexes. Promethazine HCl is reacted in acidic medium with methyl blue dye resulting in the formulation of a coloured product with a maximum absorption of 480 nm. In order to increase the sensitivity of the system, parameters of the reaction conditions were studied and optimised. Beer's law was applied on all the concentrations of 2.0 – 100.0 μg/ml, with 1.420 μg/ml and 6.088× 104 l/mol.cm as detection limit and molar absorptivity respectively. After plotting the calibration graph, the method's precision was checked and it was found the values were within the accurate range. The impact of widespread interferences on the current approach was examined. The method was utilised to estimate promethazine HCl in various pharmaceutical products available with fine recoveries in the market.</p> Mohauman Mohammad Majeed Al-Rufaie Copyright (c) 2021 Malaysian Journal of Science 2021-02-26 2021-02-26 80 92 10.22452/mjs.vol40no1.7 MAPPING LITHOLOGICAL AND MINERALOGICAL UNITS USING HYPERSPECTRAL IMAGERY https://mjs.um.edu.my/index.php/MJS/article/view/23304 <p>&nbsp;Hyperspectral images such as the Earth Observer-1 (EO-1) provides an efficient method of mapping surface mineralogy because it can measures the energy in narrower bands compared with multispectral sensors. The Kirkuk anticline northern Iraq is one of the most petroleum-rich provinces. It is characterized, that is an asymmetrical, cylindrical anticline, with a fold axis trend towards North West- East, South East. The study’s primary goal is to apply satellite processing and techniques on the Eo-1 imagery for identifying lithological and mineral units at a part of Kirkuk anticline northern Iraq. The EO-1 image was corrected at the beginning of atmospheric impacts using the FLAASH module in ENVI software. Processing of (Minimum Noise Fraction- MNF) processing was applied and then it&nbsp;reduced&nbsp;the&nbsp;dimensionality&nbsp;of&nbsp;data, as well as, the processing of (PPI) pixel purity index was applied to spatial reduction. This study tested the potential of (spectral angle mapper supervised classification-SAM) classification for mapping the lithological and mineral units using the Hyperion imagery. three different sources of endmembers or spectra are used for SAM classifications. The one:&nbsp; is done by Analytical Spectral Devices (ASD) Spectrometer. The second: reference spectra have been taken from the spectral library of USGS. Third: extracting endmembers from the purest pixels of the hyperion image, which was done by applying (MNF and PPI). The endmembers were provided, generated as the training area for SAM classification. &nbsp;The present results demonstrated the great potential of data used to map the distribution of alteration of minerals and lithological units in a part of Kirkuk anticline. The classified Hyperion image shows that Jarosite and illite are the most dominant altered minerals, as well as, the main lithological units of the upper member of Fatha formation are revealed in the core of the Kirkuk anticline with scattered and small outcrops towards the flanks.</p> Rayan Ghazi Thannoun Copyright (c) 2021 Malaysian Journal of Science 2021-02-28 2021-02-28 93 106 10.22452/mjs.vol40no1.8