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Two-Dimensional Infrared Correlation Spectroscopy, Conductor-like Screening Model for Real Solvents, and Density Functional Theory Study on the Adsorption Mechanism of Polyvinylpolypyrrolidone for Effective Phenol Removal in an Aqueous Medium

Mohammad Alwi MA, Normaya E, Ismail H, Iqbal A, Mat Piah B, Abu Samah MA, et al.

ACS Omega, 2021 Oct 05;6(39):25179-25192.
PMID: 34632177 DOI: 10.1021/acsomega.1c02699

The discharge of industrial effluents, such as phenol, into aquatic and soil environments is a global problem due to its serious negative impacts on human health and aquatic ecosystems. In this study, the ability of polyvinylpolypyrrolidone (PVPP) to remove phenol from an aqueous medium was investigated. The results showed that a significant proportion of phenol (up to 74.91%) was removed using PVPP at pH 6.5. Isotherm adsorption experiments of phenol on PVPP indicated that the best-fit adsorption was obtained using Langmuir models. The response peaks of the hydroxyl groups of phenol (OH) and the carboxyl groups (i.e., C=O) of PVPP were altered, indicating the formation of a hydrogen bond between the PVPP and phenol during phenol removal, as characterized using 1D and 2D IR spectroscopy. The resulting complexes were successfully characterized based on their thermodynamic properties, Mulliken charge, and electronic transition using the DFT approach. To clarify the types of interactions taking place in the complex systems, quantum theory of atoms in molecules (QTAIM) analysis, reduced density gradient noncovalent interaction (RDG-NCI) approach, and conductor-like screening model for real solvents (COSMO-RS) approach were also successfully calculated. The results showed that the interactions that occurred in the process of removing phenol by PVPP were through hydrogen bonding (based on RDG-NCI and COSMO-RS), which was identified as an intermediate type (∇2ρ(r) > 0 and H < 0, QTAIM). To gain a deeper understanding of how these interactions occurred, further characterization was performed based on adsorption mechanisms using molecular electrostatic potential, global reactivity, and local reactivity descriptors. The results showed that during hydrogen bond formation, PVPP acts as a nucleophile, whereas phenol acts as an electrophile and the O9 atom (i.e., donor electron) reacts with the H22 atom (i.e., acceptor electron).
The adsorption of heavy metal by Bornean oil palm shell and its potential application as constructed wetland media

Chong HL, Chia PS, Ahmad MN

Bioresour Technol, 2013 Feb;130:181-6.
PMID: 23306127 DOI: 10.1016/j.biortech.2012.11.136

Oil palm shell, a waste from palm oil industry, was cleaned and utilized as adsorbent. Its particle size distribution gave the uniformity coefficient of approximately two indicating that it can be used as filter bed media for continuous operation without resting. Its measured pH(pzc) of 4.1 is below the common pH of constructed wetland water body suggesting positive adsorption for heavy metal. The effect of various parameters on its adsorption was studied via batch experiments. The adsorption of Cu(II) and Pb(II) ions by oil palm shell showed a slightly better fit with the Freundlich compared to Langmuir. Its monolayer adsorption capacities were found to be 1.756 and 3.390mg/g for Cu(II) and Pb(II), respectively. High correlation coefficient of over 0.99 given by the pseudo-second-order model suggests that the rate limiting factor may be chemisorption. These findings suggest its potential application as constructed wetland media for the removal of heavy metal.
Optimization of protease extraction from horse mango (Mangifera foetida Lour) kernels by a response surface methodology

Ahmad MN, Liew SL, Yarmo MA, Said M

Biosci Biotechnol Biochem, 2012;76(8):1438-44.
PMID: 22878182

Protease is one of the most important industrial enzymes with a multitude of applications in both food and non-food sectors. Although most commercial proteases are microbial proteases, the potential of non-conventional protease sources, especially plants, should not be overlooked. In this study, horse mango (Mangifera foetida Lour) fruit, known to produce latex with a blistering effect upon contact with human skin, was chosen as a source of protease, and the effect of the extraction process on its protease activity evaluated. The crude enzyme was extracted from the kernels and extraction was optimized by a response surface methodology (RSM) using a central composite rotatable design (CCRD). The variables studied were pH (x(1)), CaCl(2) (x(2)), Triton X-100 (x(3)), and 1,4-dithryeitol (x(4)). The results obtained indicate that the quadratic model is significant for all the variables tested. Based on the RSM model generated, optimal extraction conditions were obtained at pH 6.0, 8.16 mM CaCl(2), 5.0% Triton X-100, and 10.0 mM DTT, and the estimated response was 95.5% (w/w). Verification test results showed that the difference between the calculated and the experimental protease activity value was only 2%. Based on the t-value, the effects of the variables arranged in ascending order of strength were CaCl(2) < pH < DTT < Triton X-100.
Nanostructured materials with plasmonic nanobiosensors for early cancer detection: A past and future prospect

Sugumaran S, Jamlos MF, Ahmad MN, Bellan CS, Schreurs D

Biosens Bioelectron, 2018 Feb 15;100:361-373.
PMID: 28946108 DOI: 10.1016/j.bios.2017.08.044

Early cancer detection and treatment is an emerging and fascinating field of plasmonic nanobiosensor research. It paves to enrich a life without affecting living cells leading to a possible survival of the patient. This review describes a past and future prospect of an integrated research field on nanostructured metamaterials, microwave transmission, surface plasmonic resonance, nanoantennas, and their manifested versatile properties with nano-biosensors towards early cancer detection to preserve human health. Interestingly, (i) microwave transmission shows more advantages than other electromagnetic radiation in reacting with biological tissues, (ii) nanostructured metamaterial (Au) with special properties like size and shape can stimulate plasmonic effects, (iii) plasmonic based nanobiosensors are to explore the efficacy for early cancer tumour detection or single molecular detection and (iv) nanoantenna wireless communication by using microwave inverse scattering nanomesh (MISN) technique instead of conventional techniques can be adopted to characterize the microwave scattered signals from the biomarkers. It reveals that the nanostructured material with plasmonic nanobiosensor paves a fascinating platform towards early detection of cancer tumour and is anticipated to be exploited as a magnificent field in the future.
Fulltext An Overview of Ontologies in Virtual Reality-Based Training for Healthcare Domain

Mohamad UH, Ahmad MN, Benferdia Y, Shapi'i A, Bajuri MY

Front Med (Lausanne), 2021;8:698855.
PMID: 34307424 DOI: 10.3389/fmed.2021.698855

Virtual reality (VR) is one of the state-of-the-art technological applications in the healthcare domain. One major aspect of VR applications in this domain includes virtual reality-based training (VRT), which simplifies the complicated visualization process of diagnosis, treatment, disease analysis, and prevention. However, not much is known on how well the domain knowledge is shared and considered in the development of VRT applications. A pertinent mechanism, known as ontology, has acted as an enabler toward making the domain knowledge more explicit. Hence, this paper presents an overview to reveal the basic concepts and explores the extent to which ontologies are used in VRT development for medical education and training in the healthcare domain. From this overview, a base of knowledge for VRT development is proposed to initiate a comprehensive strategy in creating an effective ontology design for VRT applications in the healthcare domain.
Fulltext Micro energy harvesting for IoT platform: Review analysis toward future research opportunities

Sarker MR, Riaz A, Lipu MSH, Md Saad MH, Ahmad MN, Kadir RA, et al.

Heliyon, 2024 Mar 30;10(6):e27778.
PMID: 38509887 DOI: 10.1016/j.heliyon.2024.e27778

Micro-energy harvesting (MEH) is a technology of renewable power generation which is a key technology for hosting the future low-powered electronic devices for wireless sensor networks (WSNs) and, the Internet of Things (IoT). Recent technological advancements have given rise to several resources and technologies that are boosting particular facets of society. Many researchers are now interested in studying MEH systems for ultra-low power IoT sensors and WSNs. A comprehensive study of IoT will help to manage a single MEH as a power source for multiple WSNs. The popular database from Scopus was used in this study to perform a review analysis of the MEH system for ultra-low power IoT sensors. All relevant and important literature studies published in this field were statistically analysed using a review analysis method by VOSviewer software, and research gaps, challenges and recommendations of this field were investigated. The findings of the study indicate that there has been an increasing number of literature studies published on the subject of MEH systems for IoT platforms throughout time, particularly from 2013 to 2023. The results demonstrate that 67% of manuscripts highlight problem-solving, modelling and technical overview, simulation, experimental setup and prototype. In observation, 27% of papers are based on bibliometric analysis, systematic review, survey, review and based on case study, and 2% of conference manuscripts are based on modelling, simulation, and review analysis. The top-cited articles are published in 5 different countries and 9 publishers including IEEE 51%, Elsevier 16%, MDPI 10% and others. In addition, several MEH system-related problems and challenges are noted to identify current limitations and research gaps, including technical, modelling, economic, power quality, and environmental concerns. Also, the study offers guidelines and recommendations for the improvement of future MEH technology to increase its energy efficiency, topologies, design, operational performance, and capabilities. This study's detailed information, perceptive analysis, and critical argument are expected to improve MEH research's viable future.
Development of chemometric-assisted supercritical fluid extraction of effective and natural tyrosinase inhibitor from Syzygium aqueum leaves

Zarudin NH, Normaya E, Shamsuri SS, Iqbal A, Mat Piah MB, Abdullah Z, et al.

Int J Biol Macromol, 2024 Feb;258(Pt 2):129168.
PMID: 38171432 DOI: 10.1016/j.ijbiomac.2023.129168

Tyrosinase is a key enzyme in enzymatic browning, causing quality losses in food through the oxidation process. Thus, the discovery of an effective and natural tyrosinase inhibitor via green technology is of great interest to the global food market due to food security and climate change issues. In this study, Syzygium aqueum (S. aqueum) leaves, which are known to be rich in phenolic compounds (PC), were chosen as a natural source of tyrosinase inhibitor, and the effect of the sustainable, supercritical fluid extraction (SFE) process was evaluated. Response surface methodology-assisted supercritical fluid extraction (RSM-assisted SFE) was utilized to optimize the PCs extracted from S. aqueum. The highest amount of PC was obtained at the optimum conditions (55 °C, 3350 psi, and 70 min). The IC50 (661.815 μg/mL) of the optimized extract was evaluated, and its antioxidant activity (96.8 %) was determined. Gas chromatography-mass spectrometry (GC-MS) results reveal that 2',6'-dihydroxy-4'-methoxychalcone (2,6-D4MC) (82.65 %) was the major PC in S. aqueum. Chemometric analysis indicated that 2,6-D4MC has similar chemical properties to the tyrosinase inhibitor control (kaempferol). The toxicity and physiochemical properties of the novel 2,6-D4MC from S. aqueum revealed that the 2,6-D4MC is safer than kaempferol as predicted via absorption, distribution, metabolism, and excretion (ADME) evaluation. Enzyme kinetic analysis shows that the type of inhibition of the optimized extract is non-competitive inhibition with Km = 1.55 mM and Vmax = 0.017 μM/s. High-performance liquid chromatography (HPLC) analysis shows the effectiveness of S. aqueum as a tyrosinase inhibitor. The mechanistic insight of the tyrosinase inhibition using 2,6-D4MC was successfully calculated using density functional theory (DFT) and molecular docking approaches. The findings could have a significant impact on food security development by devising a sustainable and effective tyrosinase inhibitor from waste by-products that is aligned with the United Nation's SDG 2, zero hunger.
Methyl 4-pyridyl ketone thiosemicarbazone (4-PT) as an effective and safe inhibitor of mushroom tyrosinase and antibrowning agent

Hassanuddin NA, Normaya E, Ismail H, Iqbal A, Piah MBM, Abd Hamid S, et al.

Int J Biol Macromol, 2024 Jan;255:128229.
PMID: 37981274 DOI: 10.1016/j.ijbiomac.2023.128229

Enzymatic browning is of concern as it can affect food safety and quality. In this study, an effective and safe tyrosinase inhibitor and anti-browning agent, methyl 4-pyridyl ketone thiosemicarbazone (4-PT), was synthesised and characterised using Fourier-transform infrared (FTIR) spectroscopy, CHNS elemental analysis, and proton (1H) and carbon-13 (13C) nuclear magnetic resonance (NMR) spectroscopy. The vibrational frequencies of 4-PT were studied theoretically using vibrational energy distribution analysis (VEDA). Density functional theory (DFT) was applied to elucidate its chemical properties, including the Mulliken atomic charges, molecular electrostatic potential (MEP), quantum theory of atoms in molecules (QTAIM) and reduced density gradient non-covalent interactions (RDG-NCIs). Moreover, 4-PT was compared with kojic acid in terms of its effectiveness as a tyrosinase inhibitor and anti-browning agent. The toxicity and physicochemical properties of 4-PT were predicted via ADME evaluation, which proved that 4-PT is safer than kojic acid. Experimentally, 4-PT (IC50 = 5.82 μM, browning index (10 days) = 0.292 ± 0.002) was proven to be an effective tyrosinase inhibitor and anti-browning agent compared to kojic acid (IC50 = 128.17 μM, browning index (10 days) = 0.332 ± 0.002). Furthermore, kinetic analyses indicated that the type of tyrosinase inhibition is a mixed inhibition, with Km and Vmax values of 0.85 mM and 2.78 E-09 μM/s, respectively. Finally, the mechanism of 4-PT for tyrosinase inhibition was proven by 1D, second derivative and 2D IR spectroscopy, molecular docking and molecular dynamic simulation approaches.
Business process improvement methods in healthcare: a comparative study

Ahmed ES, Ahmad MN, Othman SH

Int J Health Care Qual Assur, 2019 Jun 10;32(5):887-908.
PMID: 31195926 DOI: 10.1108/IJHCQA-07-2017-0116

PURPOSE: According to the literature concerned with this study, less than satisfactory outcomes have been achieved through implementing business process improvements methods (BPIMs) in industries, in general, and in healthcare, in particular. The existing methods used need to be enhanced in order to create more effective outcomes. There has also been a lack of studies documenting gaps or shortfalls in implementing BPIMs, to be presented to the BPI research community. Therefore, researchers of this paper have attempted to fill gaps between theory and practice. On the contrary, there is also a need to link practical outcomes in the healthcare domain with those of the BPI research community. The purpose of this paper is to review popular BPIMs, techniques and tools applied in the healthcare domain; it seeks to examine and highlight their significant roles, clarify their pros and cons, and find opportunities to enhance their impact on the achievement of more sustainable improvements in the healthcare domain.
DESIGN/METHODOLOGY/APPROACH: This study has been carried out by using a methodology combining an in-depth literature review with a comparison framework, which is called as the "Framework for Comparing Business Process Improvement Methods." The framework is composed of seven dimensions and has been adapted from four recognized, related frameworks. In addition to the in-depth review of related literature and the adapted comparison framework, researchers have conducted several interviews with healthcare BPI practitioners in different hospitals, to attain their opinions of BPI methods and tools used in their practices.
FINDINGS: The main results have indicated that significant improvements have been achieved by implementing BPIMs in the healthcare domain according to related literature. However, there were some shortfalls in the existing methods that need to be resolved. The most important of these has been the shortfall in representing and analyzing targeted domain knowledge during improvement phases. The tool currently used for representing the domain, specifically flowcharts, is very abstract and does not present the domain in a clear form. The flowchart tool also fails to clearly present the separation of concerns between business processes and the information systems processes that support a business in a given domain.
PRACTICAL IMPLICATIONS: The findings of this study can be useful for BPI practitioners and researchers, mainly within the healthcare domain. The findings can help these groups to understand BPIMs shortfalls and encourage them to consider how BPIMs can be potentially improved.
ORIGINALITY/VALUE: This researchers of this paper have proposed a comparison framework for highlighting popular BPIMs in the healthcare domain, along with their uses and shortfalls. In addition, they have conducted a deep literature review based on the practical results obtained from different healthcare institutions implementing unique BPIMs around the world. There has also been valuable interview feedback attained from BPI leaders of specific hospitals in Saudi Arabia. This combination is expected to contribute to knowledge of BPIMs from both theoretical and practical points of view.
Heavy Metals in Selected Vegetables from Markets of Faisalabad, Pakistan

Iqbal SZ, Ullah Z, Asi MR, Jinap S, Ahmad MN, Sultan MT, et al.

J Food Prot, 2018 May;81(5):806-809.
PMID: 29637809 DOI: 10.4315/0362-028X.JFP-17-256

Two hundred ten samples of selected vegetables (okra, pumpkin, tomato, potato, eggplant, spinach, and cabbage) from Faisalabad, Pakistan, were analyzed for the analysis of heavy metals: cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg). Inductively coupled plasma optical emission spectrometry was used for the analysis of heavy metals. The mean levels of Cd, Pb, As, and Hg were 0.24, 2.23, 0.58, and 7.98 mg/kg, respectively. The samples with Cd (27%), Pb (50%), and Hg (63%) exceeded the maximum residual levels set by the European Commission. The mean levels of heavy metals found in the current study are high and may pose significant health concerns for consumers. Furthermore, considerable attention should be paid to implement comprehensive monitoring and regulations.
Assessment of Fumonisin B1 Concentrations in Wheat and Barley Products in the Punjab Region of Pakistan

Iqbal SZ, Rehman B, Selamat J, Akram N, Ahmad MN, Sanny M, et al.

J Food Prot, 2020 Aug 01;83(8):1284-1288.
PMID: 32678886 DOI: 10.4315/0362-028X.JFP-19-361

ABSTRACT: A total of 133 samples of whole wheat and barley grains and wheat and barley flour collected from retail markets in the main cities of Punjab, Pakistan, were analyzed for the mycotoxin fumonisin B1 (FB1) using reverse phase high-performance liquid chromatography with fluorescence detection. Of these samples, 120 (90%) were positive for FB1, and 75 (63%) of the 120 positive samples had FB1 concentrations higher than the European Union maximum (200 μg/kg). The limit of detection was 4 μg/kg. The highest mean (±SD) concentration of FB1 was found in whole wheat samples, 980.5 ± 211.4 μg/kg. The calculated dietary intakes of FB1 from wheat and barley flours were 4,456 and 503.7 ng/g of body weight per day, respectively.
Fulltext Optimization of a protease extraction using a statistical approach for the production of an alternative meat tenderizer from Manihot esculenta roots

Ahmad MN, Hilmi NHN, Normaya E, Yarmo MA, Bulat KHK

J Food Sci Technol, 2020 Aug;57(8):2852-2862.
PMID: 32612298 DOI: 10.1007/s13197-020-04317-5

Abstract: Meat tenderness is the most important criterion in food quality because it strongly influences the consumer's satisfaction. Tenderness generally depends on connective tissue and sarcomere length of muscle. One of the effective methods for meat tenderizing is protease treatment. In this study, Manihot esculenta root was chosen as a protease source due to its skin blistering effect, suggesting the presence of strong proteolytic activity. The extraction of the crude protease was optimized by using response surface methodology (RSM) with four independent variables, which were pH (X1), CaCl2 (X2), Triton X-100 (X3) and 2-mercaptoethanol (X4). Based on the RSM model, all the independent variables were significant and the optimum extraction conditions were pH 9, 3.24 mM CaCl2, 4.12% Triton X-100 and 6.32 mM 2-mercaptoethanol. Tukey's test results showed that the difference between the expected and experimental protease activity value was 0.05%. A reduction of meat firmness was observed when samples treated with enzyme were compared with a control by using a texture analyser. Electrophoretic patterns also showed extensive proteolysis and a reduction of intensity and number of the protein bands in the treated sample. SEM clearly revealed the degradation of muscle fibres and connective tissue of meat treated with crude protease.
Graphic abstract:
The applicability of using a protease extracted from cashew fruits (Anacardium occidentale), as possible meat tenderizer: An experimental design approach

Ahmad MN, Shuhaimen MS, Normaya E, Omar MN, Iqbal A, Ku Bulat KH

J Texture Stud, 2020 10;51(5):810-829.
PMID: 32401337 DOI: 10.1111/jtxs.12529

Meat tenderness is one of the most important organoleptic properties in determining consumer acceptance in meat product marketability. Therefore, an effective meat tenderization method is sought after by exploring plant-derived proteolytic enzymes as meat tenderizer. In this study, a novel protease from Cashew was identified as a new alternative halal meat tenderizer. The extraction of cashew protease was optimized using response surface methodology (R2 = 0.9803) by varying pH, CaCl2 concentration, mixing time, and mass. pH 6.34, 7.92 mM CaCl2 concentration, 5.51 min mixing time, and 19.24 g sample mass were the optimal extraction conditions. There was no significant difference (n = 3; p
Fulltext Chemical Composition and Biological Activity of the Centipeda minima (Asteraceae)

Soetardjo S, Jong PC, Ahmad MN, Lachimanan YL, Sreenivasan S

Malays J Nutr, 2007 Mar;13(1):81-7.
PMID: 22692191 MyJurnal

The antimicrobial activity of the Centipeda minima L. (Asteraceae) extract was evaluated against seven microorganisms using the disc diffusion method. The extract showed a broad spectrum of antimicrobial activity against all the tested bacterial strains, especially Enterobacter aerogenes, Klebsiella pneumonia, Staphylococcus aureus and Yersinia enterocolitica. The chemical composition of the extract obtained from Centipeda minima was analysed by GC-MS. Twentythree compounds, constituting about 84.75 % of the total extract, were identified. The main constituents were palmitic acid (7.47%), (Z,Z)-9-,12-octadecatrienoic acid (6.52%), (Z,Z,Z)-9-,12-octadecatrienoic acid (7.01%), phytol (7.01%), naptho[2.3-b]furan-2-(3H)-on (6.21%), 1-(1,2,3,4,7,7a-hexahydro-1,4,4,5-tetramethyl-1,3a-ethano-3aH-inden-6-yl)etanon (7.95%), 1,3,5-tri-tertbutyl- benzene (4.52%), (3Z)-2-methyl-3-octen-2-ol (5.95%) and artemisia ketone (4.98%). The extract was also tested against brine shrimp for toxicity. There was no significant toxicity as it only recorded a LC50 value of 4.92 mg/ml. The study shows that the extract is a good antimicrobial agent with potential applications in public health against diseases.
Fulltext A Review of Natural Fiber-Based Filaments for 3D Printing: Filament Fabrication and Characterization

Ahmad MN, Ishak MR, Mohammad Taha M, Mustapha F, Leman Z

Materials (Basel), 2023 May 29;16(11).
PMID: 37297184 DOI: 10.3390/ma16114052

Today, additive manufacturing (AM) is the most recent technology used to produce detailed and complexly built parts for a variety of applications. The most emphasis has been given to fused deposition modeling (FDM) in the development and manufacturing fields. Natural fibers have received attention in the area of 3D printing to be employed as bio-filters with thermoplastics, which have prompted an effort for more ecologically acceptable methods of manufacturing. The development of natural fiber composite filaments for FDM requires meticulous methods and in-depth knowledge of the properties of natural fibers and their matrices. Thus, this paper reviews natural fiber-based 3D printing filaments. It covers the fabrication method and characterization of thermoplastic materials blended with natural fiber-produced wire filament. The characterization of wire filament includes the mechanical properties, dimension stability, morphological study, and surface quality. There is also a discussion of the difficulties in developing a natural fiber composite filament. Last but not least, the prospects of natural fiber-based filaments for FDM 3D printing are also discussed. It is hoped that, after reading this article, readers will have enough knowledge regarding how natural fiber composite filament for FDM is created.
Fulltext Complete Genome Sequence of Leptospira kmetyi LS 001/16, Isolated from a Soil Sample Associated with a Leptospirosis Patient in Kelantan, Malaysia

Yusof NY, Muhammad Yusoff F, Muhammad Harish S, Ahmad MN, Khalid MF, Mohd Nor F, et al.

Microbiol Resour Announc, 2019 Jul 11;8(28).
PMID: 31296668 DOI: 10.1128/MRA.00015-19

The Gram-negative pathogenic spirochetal bacteria Leptospira spp. cause leptospirosis in humans and livestock animals. Leptospira kmetyi strain LS 001/16 was isolated from a soil sample associated with a leptospirosis patient in Kelantan, which is among the states in Malaysia with a high reported number of disease cases. Here, we report the complete genome sequence of Leptospira kmetyi strain LS 001/16.
Fulltext Floating ZnO QDs-Modified TiO2/LLDPE Hybrid Polymer Film for the Effective Photodegradation of Tetracycline under Fluorescent Light Irradiation: Synthesis and Characterisation

Iqbal A, Saidu U, Adam F, Sreekantan S, Yahaya N, Ahmad MN, et al.

Molecules, 2021 Apr 25;26(9).
PMID: 33923041 DOI: 10.3390/molecules26092509

In this work, mesoporous TiO2-modified ZnO quantum dots (QDs) were immobilised on a linear low-density polyethylene (LLDPE) polymer using a solution casting method for the photodegradation of tetracycline (TC) antibiotics under fluorescent light irradiation. Various spectroscopic and microscopic techniques were used to investigate the physicochemical properties of the floating hybrid polymer film catalyst (8%-ZT@LLDPE). The highest removal (89.5%) of TC (40 mg/L) was achieved within 90 min at pH 9 due to enhanced water uptake by the LDDPE film and the surface roughness of the hybrid film. The formation of heterojunctions increased the separation of photogenerated electron-hole pairs. The QDs size-dependent quantum confinement effect leads to the displacement of the conduction band potential of ZnO QDs to more negative energy values than TiO2. The displacement generates more reactive species with higher oxidation ability. The highly stable film photocatalyst can be separated easily and can be repeatedly used up to 8 cycles without significant loss in the photocatalytic ability. The scavenging test indicates that the main species responsible for the photodegradation was O2●-. The proposed photodegradation mechanism of TC was demonstrated in further detail based on the intermediates detected by LC-time-of-flight/mass spectrometry (LC/TOF-MS).
Fulltext Alpha-Glucosidase Enzyme Biosensor for the Electrochemical Measurement of Antidiabetic Potential of Medicinal Plants

Mohiuddin M, Arbain D, Islam AK, Ahmad MS, Ahmad MN

Nanoscale Res Lett, 2016 Dec;11(1):95.
PMID: 26887579 DOI: 10.1186/s11671-016-1292-1

A biosensor for measuring the antidiabetic potential of medicinal plants was developed by covalent immobilization of α-glucosidase (AG) enzyme onto amine-functionalized multi-walled carbon nanotubes (MWCNTs-NH2). The immobilized enzyme was entrapped in freeze-thawed polyvinyl alcohol (PVA) together with p-nitrophenyl-α-D-glucopyranoside (PNPG) on the screen-printed carbon electrode at low pH to prevent the premature reaction between PNPG and AG enzyme. The enzymatic reaction within the biosensor is inhibited by bioactive compounds in the medicinal plant extracts. The capability of medicinal plants to inhibit the AG enzyme on the electrode correlates to the potential of the medicinal plants to inhibit the production of glucose from the carbohydrate in the human body. Thus, the inhibition indicates the antidiabetic potential of the medicinal plants. The performance of the biosensor was evaluated to measure the antidiabetic potential of three medicinal plants such as Tebengau (Ehretis laevis), Cemumar (Micromelum pubescens), and Kedondong (Spondias dulcis) and acarbose (commercial antidiabetic drug) via cyclic voltammetry, amperometry, and spectrophotometry. The cyclic voltammetry (CV) response for the inhibition of the AG enzyme activity by Tebengau plant extracts showed a linear relation in the range from 0.423-8.29 μA, and the inhibition detection limit was 0.253 μA. The biosensor exhibited good sensitivity (0.422 μA/mg Tebengau plant extracts) and rapid response (22 s). The biosensor retains approximately 82.16 % of its initial activity even after 30 days of storage at 4 °C.
Fulltext Validation of key components in designing a social skills training content using virtual reality for high functioning autism youth-A Fuzzy Delphi method

Ahmad Basri MAF, Wan Ismail WS, Kamal Nor N, Mohd Tohit N, Ahmad MN, Mohamad Aun NS, et al.

PLoS One, 2024;19(4):e0301517.
PMID: 38574084 DOI: 10.1371/journal.pone.0301517

The use of virtual reality in social skills training for high functioning autism spectrum disorder (HFASD) youth has been found to be engaging and enjoyable. Despite the promising results, previous literature indicates that there has been no consensus on the social skills target in the training content. There is also limited research on how evidence-based strategies like cognitive and behaviour techniques are instantiated into the VR environment to teach social skills. The aim of this study is to determine the key components to design a social skills training content using virtual reality for youths with HFASD. The Fuzzy Delphi method (FDM) was used to obtain expert consensus on social skills difficulties and cognitive behavioral techniques included in the content in three phases. In phase 1, a questionnaire was developed from in-depth interviews and scientific literature review. The in-depth interviews were conducted with 13 HFASD youth, 7 parents and 6 experts. In phase 2, 3 experts rated the relevance of the items in the questionnaire using an item-level content validity index (I-CVI) assessment. In phase 3, the questionnaire was distributed to 10 experts to rate their level of agreement on each component using a 7-point Likert scale. Components that received a value above 75%, threshold value (d) ≤ 0.2, fuzzy score (A) ≥ α - cut value = 0.5 and higher rank based on defuzzification score were prioritized to be included in the content. Items that received higher expert consensus on social skills difficulties included assessing non-verbal responses, initiating, maintaining, and leaving conversations, emotional difficulties and difficulties in perspective taking. Cognitive and behavioral techniques that received higher expert consensus were psychoeducation, modelling, relaxation techniques, reinforcements, and perspective-taking questions. These key components can be used as a framework for the development of virtual learning content for social skills training in future studies.
Fulltext Life Cycle Assessment (LCA) of Particleboard: Investigation of the Environmental Parameters

Mohd Azman MAH, Ahmad Sobri S, Norizan MN, Ahmad MN, Wan Ismail WOAS, Hambali KA, et al.

Polymers (Basel), 2021 Jun 22;13(13).
PMID: 34206568 DOI: 10.3390/polym13132043

Particleboard is not entirely a wood replacement but a particular material with its properties, making it more effective at different times than heavy or solid wood. The world's biggest concern is environmental problems with formaldehyde as a particulate board binder that can lead to human carcinogenic agents. A cradle-to-gate life cycle assessment (LCA) of particleboard production was performed using openLCA software. The impact assessment was carried out according to the software's features. This preliminary investigation aims to analyze the chemical composition of particleboard and identify its environmental impact. The Fourier-transform infrared spectroscopy (FTIR) system was used to track the functional group of aliphatic hydrocarbons, inorganic phosphates, and main aliphatic alcohols found in particleboards made in Malaysia. Based on the FTIR results, aliphatic groups were found in numerous aggravates that the spectroscopic infrared was likely to experience. The most important vibrational modes were C-H, at approximately 3000 cm-1, and -CH deformations around 1460 cm-1 and 1380 cm-1. Eight effect groups demonstrated that 100% of the input and all analyses produced the same relative outcome. The life cycle of a product is determined by pollution of the air, water, and soil. Thus, particleboard has a minimal impact on the environment, except for global warming.

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