Table of contents

International Fundamentum Science Symposium (iFunS) 2018

PREFACE

From 25 to 26 June 2018, the International Fundamentum Science Symposium 2018 was held in Kuala Terengganu – the heritage waterfront city, situated at the east coast of peninsular Malaysia. This first ever scientific meeting hosted by the School of Fundamental Science, Universiti Malaysia Terengganu (UMT) and co-organized by Academy Sciences of Malaysia (ASM). With the theme "Exploring Possibilities Through Fundamental Sciences", this symposium was divided to three main sub-themes which were Fundamental Chemistry, Fundamental Physics and Fundamental Biology.

The aim of this symposium was to promote and encourage the fundamental research among the researchers. It is important to note that although fundamental studies do not pursue immediate commercial objectives, nevertheless, findings of fundamental studies may result in innovations, as well as generating solutions to practical problems. In fact, the findings and knowledge of fundamental studies in chemistry, physics and biology will generate new and advanced technologies such as nanotechnology, green technology, biotechnology, tissues engineering and etc. The conference was attended by over 80 specialists from leading universities and research institutes, as well as representatives of the scientific community from United Kingdom, Indonesia and Singapore. More than 60 papers were selected to go through a strict double blinded peer reviewed process. In turn, these selected papers were published in IOP Conference Series: Material Science and Engineering.

We would like to thank Associate Editors and members of reviewers for their kind assistance in reviewing these papers.

List of Editors, Committees and Conference Photographs are available in this pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Biofilm based on gellan gum, was prepared by evaporative casting technique, and its properties were evaluated. The tensile strength (TS) and elongation-at-break (EAB) of the GGVCO-NOR films were found to be 9 MPa and 7.3%, respectively. The swelling properties and water vapor transmission rates of the prepared films were found to be 278% and 212 g m-2 d-1, respectively, after 24 hours. Surface morphology of the film revealed the presence of the pores. From the anti-bacterial study, it was found that the inhibition zone of GG-NOR and GG-VCONOR film were 5.3±0.06 mm and 5.7±0.06 mm against gram-positive (Staphylococcus aureus) and 5.0±0.01 mm and 6.3±0.06 mm againts gram-negative bacteria (Escherichia coli).

Essential Oil (EO) of Nepeta Cataria L. has an attractive benefit due to its potential as alternatives compound of controlling mosquito vectors especially Aedes aegypti. This paper reports on application of response surface methodology (RSM) using Box Behnken design (BBD) to optimize the extraction of EO from Nepeta Cataria L. The parameters experimented were the time of extraction (120-360 min), temperature of sonication (30-50°C) and ratio of sample to solvent (30-60gram/150ml). The extraction was conducted by using soxhlet method assisted by ultrasound using ethanol (polar solvent). Statistical analysis and analysis of variance indicated that the time of extraction and ratio of sample to solvent are significant factors (p<0.05) affecting the yield while the temperature of sonication was insignificant (p>0.05). For the modelled extraction, the minimum critical values for ethanol solvent was 269.48 minute, 40.18°C and 33.22 gram/150 ml ethanol. Recovery of oil when 1 gram of raw material was used per 150 ml of solvent was 2.32%. By using High Performance Liquid Chromatography with Ultraviolet detector (HPLC-UV), nepetalactone was detected at time of 12.694 min and 13.941 min using absorption peak 228nm.

A novel organic-inorganic nanocomposite based on carbamate insecticide-zinc layered hydroxide modified with sodium dodecyl sulphate nanocomposite (ZLH-SDS-PRO) was synthesized through ion exchange method of propoxur with commercially available zinc nitrate at various concentrations. The intercalation of propoxur into the interlayer of zinc layered hydroxide modified sodium dodecyl sulphate (ZLH-SDS) was confirmed by PXRD analysis with the basal spacing of the pure phase nanocomposite at 33.1 Å. The propoxur anions suggested to be arranged in a bilayer form between the galleries of zinc layered hydroxide. The intercalation also supported by Fourier transforms infrared spectra (FTIR) that showing the resemblance spectra between the host and the resulting nanocomposite. The elemental analysis estimates the loading of propoxur anion in the nanocomposite to be 88.17 %. The surface area analysis revealed mesoporous-type material properties for both the host and resulting nanocomposite. The thermal study shows a significant improved thermal stability of the propoxur anion compared to its pure form. The effect of intercalation of propoxur on the morphology of the host, ZLH-SDS crystals was investigated by field emission scanning electron microscopy (FESEM).

The toxicity of organic solvent to human and environment has triggered researchers to find an alternative green solvent for the past 20 years. Deep eutectic solvent (DES) is the newly emerging green solvent that is being utilized in biocatalysis. The boiling point of DES is higher than conventional organic solvent thus enables for lipase to perform at its optimum temperature. However, the transesterification reaction in DES is limited due to its high viscosity. Therefore, water was added to DES media to reduce its viscosity. This study reported on the use of choline-based DES for lipase-catalyzed transesterification of ethyl caffeate and glycerol. The transesterification reactions in DES comprised of choline chloride and urea at molar ratio 1:2 resulted in high conversion of ethyl caffeate (over 90%) under the following parameters : enzyme loading (1250 Unit Activity); amount of water (20 vol%) and agitation speed (200 rpm). This work could provide an insight to the potential of DES as a promising alternative solvent for the production of glyceryl caffeate esters due to high conversion, faster reaction time and reduction of dangerous organic solvent consumption.

Co²⁺-complex imprinted polymer (Co-IIP) was prepared by ionic imprinting technology for selective removal of Co²⁺ ions from aqueous solution. Co²⁺ which act as a template ion established a coordination linkage with dipicolinic acid before being copolymerized with functional monomer (methacrylic acid) in the presence of cross-linker (ethylene glycol dimethacrylate) and initiator (2,2'-azobisisobutyronitrile). The surface features and functional groups present in imprinted polymer were characterized by scanning electron micrograph and infrared spectra. The non-imprinted polymer (NIP) was produced simultaneously to serve as controlled polymer. From the isotherm study, adsorption of Co²⁺ ions by ion imprinted polymer (IIP) followed Langmuir isotherm model, which indicates the sorption can be described by monolayer adsorption by give the maximum adsorption capacity was 19.57 mg g⁻¹. This value was comparable to the experimental value which was 18.48 mg g⁻¹ and better affinity compared to NIP. The adsorption kinetics fit a pseudo-second-order and adsorption equilibrium time was around 30 minutes. The present work has successfully synthesized Co-IIP particles with good potential in recognition of Co²⁺ ions.

The aim of this work was to investigate the effect of gellan gum (GG), calcium chloride (CaCl₂) and glycerol concentration on physical appearance of the film. It was found that, after heated at 50 °C for 24, hours the films were successfully produced using low amount of GG (0.50, 0.75, and 1.00 g) with effective concentration of CaCl₂ (5 mM) and glycerol (50 % (w/w)). The film was not well dried at 40 °C while at 70 and 100 °C, the film formed was easily to rupture due to the overheated. At 1.5 g GG the film cannot be produced due to the formation of highly viscos and sticky formulated solution. The effective glycerol concentration was within the range of 30-50 % (w/w, based on GG weight). At 60 and 70 % (w/w) of glycerol, the films started to distort at the edge due to high concentration of the plasticizer.

This paper reports the preparation of electrospun polylactic (PLA) nanofiber coated with carrageenan (CRG) and polyethylene glycol (PEG). CRG was utilized to increase the hydrophilicty while PEG was used to create strong bonding between the two polymers. The nanocomposites films (PLA/CRG-PEG) were successfully prepared. The presence of CRG improves the hydrophilicity of the nanofiber mat (22.45°) while the addition of PEG increased the mechanical strength. This new approach would enable the applications of electrospun PLA for more hydrophilic environment, especially for medical devices or materials

Poly(N-isopropylacrylamide) (PNIPAM) nanoparticles were successfully synthesized via emulsion polymerization techniques using different critical micelle concentrations (CMCs) of sodium dodecyl sulphate (SDS) surfactant, temperature and time of polymerization. The effects of surfactant concentrations on emulsion polymerization of PNIPAM nanoparticles have been discussed. Potassium persulfate (KPS) and N,N'-methylenebisacrylamide (MBAA) were used as initiator and cross-linker, respectively throughout the emulsion polymerization. The formation of PNIPAM nanoparticles was confirmed by Fourier transform infrared spectroscopy (FTIR) with absorption peaks observed at 2997 and 2930 cm-1 for C-H stretching of CH3 and CH2 groups, 1459 cm-1 for 2° amide C=O stretch, 3310 cm-1 and 3275 cm-1 for N-H stretching band. The particle size and morphology of PNIPAM nanoparticles were determined using scanning electron microscopy (SEM) where large aggregation of PNIPAM nanoparticles were observed with average diameters in the range of 20 – 50 μm and the appearance of pore structure on the hydrogel surface. Thermal stability of PNIPAM nanoparticles were obtained by thermogravimetric analysis (TGA) where it showed the percentage of mass loss at certain temperature.

Electrochemical sensing of DNA has been known to be the easiest and sensitive way reported so far. This study focuses on the effect of recognition layer's length in E-DNA sensor, a theoretical approach has been carried out to four different length of Schiff bases derivatives which involved four different length of R group attached (3, 6, 9 and 12 alkane chain). This study has been carried out using density functional theory (DFT) by using Gaussian09 software package 6-31G (d,p) basis set for all the calculations involved. Structure drawing was performed with GaussView 5.0. After optimization, energy, dipole moment, HOMO, LUMO, hardness (η), softness (σ) and energy gap. Dipole moment value is an important value to determine the optimum length of recognition layer. Preliminary result showed that the length does not play an important role in E-DNA sensor.

In this study, [Ir(2,4-F₂ppy)₂(2-(1,2,4-triazol-1-yl)pyridine>)]PF₆ (C1), [Ir(2,4-F₂ppy)₂(2-(2-(4-dimethylbenzyl)-1,2,4-triazol-1-yl)pyridine)]PF₆ (C2) and [Ir(2,4-F₂ppy)₂(2(2-hexyl-1,2,4-triazol-1-yl)pyridine)]PF₆ (C3) complexes were successfully synthesised by refluxing the mixture of dichloro-bridged iridium(III) dimer, [Ir(2,4-F₂ppy)₂(μ-Cl)]₂ and corresponding triazolium salt containing N-heterocyclic carbene (NHC) as ancillary ligands. ¹H NMR of all complexes display well-resolved signals between 10.00-5.00 ppm assign to proton at the aromatic region for penylpyridine and pyridyltriazole. Spectra of C2 and C3 also display signals at aliphatic region (singlets) between 0.80-1.50 ppm that proved the presence of methylbenzyl and hexyl substituent on the pyridyltriazole ring. In addition, IR analysis reported the presence of C=C and C=N stretching of pyridine at range 1570-1470cm⁻¹ and C-H stretching of aromatic pyridine at 2990-3080cm⁻¹. Besides, UV-Vis absorption data showed that the low-energy metal-to-ligand charge-transfer (MLCT) band in C2 (364 nm) is significantly blue-shifted compared to C1 (375 nm) and C3 (381 nm). Overall, this study reported the synthesis and spectroscopic study of phenylpyridine Ir(III) complexes with various types of pyridyltriazole (NHC ancillary ligands).

The growing ecological and environmental consciousness has driven efforts for development of new innovative products for various end-use applications. Nanotechnology plays an important role in the development of such products. Electrospun nanofibers which are produced from electrospinning technique are likely to be the next novel nanomaterials designated in the consumer products. Cellulose nanocrystals (CNCs) are nanoscale cellulose produced from renewable resources with strong reinforcing potential when included in a polymer matrix. Nanotechnology plays an important role in the development of such products. Electrospun nanofibers which are produced from electrospinning technique are likely to be the next novel nanomaterials designated in the consumer products. Electrospinning technique is the known prevalent technology for the manufacturing of nano-sized diameter fibers with the advanced functionalities. Various polymers have been successfully electrospun into ultrafine fibers in recent years mostly in solvent solution and some in melt. In this paper, a mini review is presented on the researches and developments related to electrospun polymer nanofibers.

The present study reports on the capability of CTA / Aliquat 336 electrospun fibers in extracting Cd(II) from aqueous phase. The CTA/Aliquat 336 electrospun fibers were produced by electrospun a polymer solution containing CTA and Aliquat 336 in DMC and methanol with a ratio of 8:2 respectively. The effect of different Aliquat 336 concentration on the performance of Cd(II) removal was examined. Extraction experiment was conducted in a batch mode using 5 ppm of Cd(II) in 1 M HCl solution. Results showed that the extraction of Cd(II) increased as Aliquat 336 concentration increased. Morphology structure of the CTA / Aliquat 336 electrospun fibers were also carried out using scanning electron microscopy (SEM).

The textile industry is one of the swiftest thriving industries contributing to the economic growth of Malaysia, particularly in east coast peninsular state. As the popularity of industry increases, the water usage was found to be elevated and eventually causes high expel rate of wastewater with excessive dye pollutants. In this study, anionic clay of nickel/aluminium layered double hydroxide (NiAL), was chosen to be studied as a potential adsorbent for anionic dye, namely Alizarin Red S (AR). The NiAL was synthesised via co-precipitation method and were characterized using powder X-Ray diffraction (PXRD) and Fourier Transform Infrared spectrophotometer (FTIR). NiAL was then used as adsorbent for the removal of AR dye in aqueous solution which was tested at different NiAL dosages. The experimental data were analysed using adsorption isotherm models and the AR adsorption was found to obey the Langmuir model.

The capture and storage of carbon dioxide has been identified as one potential solution to greenhouse gas driven climate change. Efficient separation technologies are required for removal of carbon dioxide from flue gas streams to allow this solution to be widely implemented. This study is mainly focusing on the effect of different concentration of polydimethyl siloxane (PDMS) in dip-coating solution on the membrane's performance. The asymmetric thin flat sheet membrane was prepared by dry / wet phase inversion process consisting 20 %w/v of polysulfone (PSf) as the support layer polymer and 80 %w/v of N-methyl-2-pyrrolidone (NMP) as the solvent. PDMS was coated on the support PSf membrane with the composition of 10, 15 and 20 wt% of PSf in n-hexane respectively. The characterization of morphology of TFC membrane will be conducted by using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR). The membrane's performance and the selectivity of CO₂/N₂ separation will be determined by conducting gas permeation test. The result obtained, show that membrane with highest concentration of PDMS in dip-coating solution give a highest performance in selectivity and unfortunately it contributes to lower permeability. It is vice versa from the membrane without PDMS in the top layer which gives highest value of permeability but lowest in selectivity. From the characterization and permeation test of the membrane, hereby the membrane with highest percentage of PDMS should be selected for the future development of membrane due to its highest value of selectivity which contributes to highest efficiency in separating the gas.

Zinc (Zn) is a type of element that are commonly found in the Earth's environment and may be originated either naturally from the environment or produced by human activities. Zn has been identified as a hazardous metal which can give harmful effects to human health and Earth's environment. Therefore, it is very important to develop a simplest method which does not require laborious work in order to detect Zn metal ions. Ligand of AFCMSH was synthesized by the mean of reflux reaction between 2-amino-3-formylchromone (AFC) and 4methylbenzenesulfonylhydrazide (MSH). The molecular structure of the ligand in the ground state was optimized using density functional theory (DFT/B3LYP) method with 6-311G(d,p) basis set. Characterization of ligand was conducted using spectroscopic techniques such as Fourier Transform Infra-Red spectroscopy (FT-IR), Gas Chromatography Mass Spectrometry (GC-MS), Nuclear Magnetic Resonance spectroscopy (NMR) and Ultraviolet-visible spectroscopy (UV-VIS). Meanwhile the fluorescence property of ligand in the presence of metal cations was recorded using Fluorescence Spectrophotometer. Ligand shows almost no fluorescence property in the presence of various metal ions except for Zn²⁺ ion when observed under UV light. Interestingly, ligand exhibits a remarkable fluorescence response by giving yellow-green fluorescence with strong fluorescence intensity in the emission spectrum at 501nm at excitation of 375 nm upon addition of one equivalent of Zn²⁺.

Schiff bases consist of aromatic have been used in various application including biological, inorganic and analytical chemistry. It also has been applied in optical and electrochemical sensors to enable detection of enhance selectivity and sensitivity of the sensors. These compounds might give excellent prospect in sensor. Schiff bases derived from 4-(4- aminostyryl)benzonitrile and three 4-alkoxybenzaldehyde derivatives are synthesis using ethanol as solvent. All compounds were characterized by Fourier transform-infrared spectroscopy (FT-IR), UV-Vis spectrophotometer and Nuclear Magnetic Resonance (NMR). FTIR showed formation of C=N (imine) stretching vibrations at range of 1604 cm⁻¹ to 1609 cm⁻¹. In UV-vis, π-π* electronic transition of the C=N can be observed at peak range 361 nm. While in the δH NMR the peak of CH=N (Imine) group was found at δ 8.32-8.34 ppm and ¹³C NMR for three Schiff bases were discovered at δ 158.72, 158.73 and 158.71 ppm. In previous study there are several types of linker that have been used in E-DNA, especially alkanethiol. In this study, three new Schiff base derivatives have been synthesized and characterized due to it promising in sensor which prompted us to apply its as future potential linker in electrochemical DNA sensor.

In this study, Al₂O₃-graphene nanoplatelets (GNP) nanocomposite was evaluated on its properties and performance towards methyl orange (MO) dye. Al₂O₃-GNP nanocomposite was prepared by conventional hydrothermal at 200°C for 24 h. The result showed the crystallite size of Al₂O₃ is decreased and internal strain increased with the increased GNP content. The particle size of nanocomposite becomes larger with the increment GNP amount in the nanocomposite. Nanocomposite with lower graphene contents (20 wt%) and higher Al₂O₃ contents performed (80 wt%) the optimum for the MO absorption with efficiency of 75% in visible light.

Synthesis of 400 nm average size poly (methyl methacrylate) (PMMA) and fabrication onto surface-enhanced Raman scattering (SERS) active substrate were presented.

"Bottom-up" technique was employed to fabricate SERS active substrate while PMMA suspension was obtained via surfactant-free emulsion polymerization. Morphology of fabricated PMMA photonic crystals (PMMAPc) SERS substrate was observed through scanning electron microscopy (SEM) with 20 000 magnification at 10 kV power. Photonic properties measurement was carried out using ocean optic spectrometry at range of 800 nm to 900 nm. Thermal resistivity study was measured through thermogalvanic analysis (TGA) over a range of 0 °C to 500 °C. Subsequently, enhancement percentage assessment by Raman spectroscopy provided evidence that PMMAPc SERS substrate potentiality towards Raman signal by using 4-aminothiolphenol (4-ATP) as probe molecule. Evidence from SEM supported that highly homogenous PMMA particles fabricated onto thin film brings wellordered arrangement in agreement with photonic crystals design. The proposed model was assessed experimentally using ocean optic spectrometry show a wide dip transmission at 899 nm and thermally stable up to 336 °C. Raman spectrum of 4-ATP using normal Raman analysis (without using PMMAPc SERS substrate) and using PMMAPc substrate support the results of the improvement of Raman signal upon 45 %. Low cost and large area fabrication would suggest PMMAPc as convenient yet affordable active SERS substrate for advance and fast detection.

Pure TiO₂ and a series of Al-Fe-Cu tri-doped TiO₂ were synthesized by using in-situ hydrothermal method. The synthesized materials were characterized using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). The photocatalytic activity of the samples was evaluated for degradation of methylene blue (5mgL⁻¹) in aqueous solution under uv-visible light (λ = <420 nm). The XRD pattern showed that all samples exhibited anatase phase after calcined at temperature 500°C with crystallite size in the range of 10.00-13.23 nm. The FTIR spectra showed three important vibrational modes for vOH, δOH and vTiO that were assigned at range 3411.75-3399.27 cm⁻¹, 1626.911630.53 cm⁻¹ and 503.30-530.93 cm⁻¹, respectively. The degradation rate of Al(1mmol)-Fe-Cu tri-doped TiO₂ showed the highest photocatalytic degradation with 93% compared to pure TiO₂, Al(2 mmol)-Fe-Cu tri-doped TiO₂ and Al(3mmol)-Fe-Cu tri-doped TiO₂ were calculated as 76%, 85% and 80%, respectively. Hence, it can be seen that, the amount of Al ion-doping have influence on the photocatalytic degradation.

This study aimed to enhance photocatalytic activity of TiO₂ photocatalyst in methylene blue (MB) photodegradation. Boron (B)-sulphur (S) codoped TiO₂ photocatalysts were synthesized using sol-gel method with addition of TTIP as precursor. The reaction was carried out using two dopants (0.05 wt. % of S and 0-7 wt. % of B), stirred for 4 hours followed by washing until pH 7. The samples were dried in oven at 100 °C for 12 hours and calcined at 560 °C with heating rate 5 °C/min. Photodegradation of MB were carried out under ultraviolet (UV) irradiation. The undoped and codoped TiO₂ photocatalysts were characterized using FTIR, TGA, XRD and UV-Vis. The presence of TiO₂ peaks (687-719 cm⁻¹) were confirmed using FTIR analysis and thermal analysis of samples has been evaluated using TGA instrument. XRD analysis revealed the presence of anatase phase at 560 °C and the crystallite size (12-22 nm). Undoped and codoped TiO₂ were tested in removing MB from the solution and the results possessed codoped TiO₂ with 3 wt. % of B was the best photocatalyst for this study by degrading 59% and 100% of MB after 10 and 35 minutes, respectively.

The Recent work discovers the evaluation on alumina-titania-carbon nanotube (Al₂O₃–TiO₂–CNT) composite prepared by powder metallurgy method. The properties of Al₂O₃–TiO₂–CNT composite have high hardness, chemical and thermal resistance, wear and corrosion resistance but lacking to low fracture toughness which lead to brittle properties. Hence, CNTwas added to the system due to attractive mechanical properties, low density and high fracture toughness. Elemental powders of Al₂O₃–TiO₂–CNT were milling in low energy ball milling using different milling time at 15, 30, 45 and 60 hours. The peak XRD of TiO₂ and CNT become diminished with increasing milling time. The powder that milled at 60 hour possible to has lowest crystallite size and highest internal strain due to finer and homogenous particle size deform during milling.

This study describes the facile synthesis and crystal structure of one dimensional coordination polymer which has been successfully obtained from reaction between semi rigid monoamide ligand namel N6-[(4-pyridylmethylamino)carbonyl]-2-pyridinecarboxylic acid methyl ester (L2) with copper perchlorate. The synthesized coordination polymer, with formula given by elemental analysis and X-ray crystallography as {[Cu3(L2-CH3)3(L2)2(H2O)2(CH3OH)](ClO4)3}n was crystallized in monoclinic crystal system and space group C2/c. The asymmetric unit of this complex consists of three copper atoms, three anionic carboxylate forms of ligand L2, two neutral forms of ligand L2 and four partially-occupied non-coordinated perchlorate anions. This asymmetric unit acts as the repeating fragment to form one-dimensional networks which was stabilized by intramolecular hydrogen bonds.

Success in wound treatment requires careful assessment on the wound and suitable wound dressing. In this project a novel incorporation of both curcumin and limonene into gellan gum hydrogel have been done. This system is believed to have a better permeation of curcumin to the target area. The samples prepared are denoted as GGTF for gellan gum thin film, Cur-GGTF for curcumin gellan gum thin film. Samples of Cur-GGTF incorporated with limonene with three different concentrations of 0.0005 M, 0.0006 M and 0.0007 M are known as CurLim-GGTF05, CurLim-GGTF06 and CurLim-GGTF07, respectively. The hydrogels were crosslinked by calcium ion. From the FTIR analysis, all of the expected functional groups from the gellan gum, curcumin and limonene were found present in the hydrogel samples. The TGA-DTG analysis has proven that the incorporation of limonene into hydrogels has decreased the thermal stability of the hydrogels. The addition of limonene has caused a hike in the gel fractions of the hydrogels. The water vapour transmission rate (WVTR) and swelling test showed that the introductions of high concentrations of limonene into the hydrogels have hampered the absorption of water molecules thus causing the swelling degree to decrease.

In this study, sodium alginate (SA) hydrogel film incorporated with Manuka honey was successfully developed. Swelling properties and gel fraction of hydrogel films decreased upon addition of Manuka honey in SA film. SA hydrogel film has the highest swelling percentage at 512 ± 21% and decreased to 197 ± 9% in SA hydrogel film containing 10% (v/v) of Manuka honey (SA-H10). In contrast, the SA-H10 hydrogel film has the lowest gel fraction at 12 ± 1% compared to SA hydrogel film at 45 ± 3%. The Young's Modulus of SA hydrogel films with Manuka honey were increased as the concentrations of Manuka honey increased. The hydrogel films with higher concentration of Manuka honey (SA-H10) were soft with tensile strength, tensile strain and Young's Modulus at 1.06 ± 3 MPa, 15 ±1% and 34 ± 3 MPa, respectively. The water vapour transmission rates (WVTRs) of SA-H hydrogel films were in the range of 1051 ± 48 – 1428 ± 84 g m⁻² d⁻¹, which comparable to WVTRs values with the commercial wound dressing products. The SA-H hydrogel films can be a potential material to be used as a wound dressing product.

Carbon nanotubes (CNTs) is one of the most unique nanomaterials in the field of nanotechnology because of their high strength, stiffness and electrical conductivity. Growth CNTs through chemical vapour deposition (CVD) method offers controlled synthesis of ordered and aligned CNTs. Catalytic growth also can be designed CNTs in variety forms either straight filament, helically wound tubes and bent. Recently, transition metal incorporated Mobil Composition Matter (known as MCM41 ) molecular sieves as growth catalyst has been used for the production of CNTs. The invention of mesoporous molecular sieves by Mobil researchers in 1992 has given a new direction to the field of porous materials. MCM41 exhibit a good hexagonal arrangement, uniform channel structure, tuneable pore size (15-100 Å) and large surface area (≈1200 m²g⁻¹). Transition metal catalysts can be incorporated into the pore walls of the mesoporous molecular sieves and stabilizing the dispersed catalytic sites. The mesoporosity and the well-defined pore structure in combination with high surface area make MCM41 materials as promising candidates for the synthesis of CNTs. In this article, we review and discuss the role of catalyst and their catalyst support using MCM mesoporous material.

This study investigates the physical properties, compression strength and thermal behaviors of the Kelcogel hydrogel films. Kelcogel hydrogel film at 2 mm thickness (KEL-2) shows the optimum swelling ratio and compression strength at 99 ± 10% and 155 ± 33 kPa, respectively compared to other samples. The KEL-2 hydrogel films were further incorporated with acetaminophen and the properties were examined. The swelling ratio and compression strength of KEL-2 hydrogel films contained 30% (w/w) of acetaminophen (KEL-A30) show optimum values at 108 ± 10% and 423 ± 42 kPa, respectively. The WVTRs of the KEL hydrogel films incorporated acetaminophen were in the range of 2329 - 4699 g m⁻² d⁻¹. Thermal stability of KEL hydrogel films also increased depending to the amount of the acetaminophen added. This study shows that the addition of acetaminophen improved the physical properties, compressive strength and thermal behavior of the Kelcogel hydrogel film and promising to be applied as dressing materials.

The aim of this work was to investigate the physiochemical and mechanical properties of gellan gum incorporating norfloxacin (GG-NOR) biofilm at different concentration of NOR. Four different concentration of NOR (0.01%, 0.1%, 0.5%, and 1% (w/w)) were used to produce GG-NOR biofilms. The biofilms was successfully produced with good shape and were transparent at ∼95%. The addition of norfloxacin was found to increase the toughness and elongation-at-break values of biofilm to 0.52 J g⁻¹ and 3.8 % at higher concentration of NOR. On top of that, the thermal stability of biofilm also was increased when the concentration of norfloxacin was increased attributed to the interaction between gellan gum and norfloxacin as proved by FTIR analysis.

Ethanol extract and essential oil of Citrus sinensis (L.) peels have been characterized and compared for its antibacterial activity. Ethanol extract of C. sinensis (L.) peels was obtained by Soxhlet extraction method in ethanol with purity of 96% and the essential oil was obtained by distillation method for 5 hours at 100°C. The antibacterial activities of the extracts were investigated against Staphylococcus aureus. The experimental results showed that the ethanol extract yielded 29.50% (w/w), with total flavonoid compounds of 4.74 mg/g and polyphenolic of 20.54 mg/g, while the water extract (essential oil) yielded 6.80% (w/w) with total polyphenolic compounds of 0.65 mg/g. The flavonoid compound was not observed in the essential oil obtained from distillation method. The bioactive compounds in the ethanol extract obtained by Soxhlet extraction are larger than those found in the essential oil obtained by distillation method. The ethanol extract showed stronger growth inhibitory effect of Staphylococcus aureus with zone inhibition diameter of 18 mm, whereas the essential oil and the commercial d-limonene extract had similar zone inhibition diameter of 15 mm.

In the present study, we describe the application pre-treated graphite waste (PTG) and graphite waste/Fe₃O₄ composites as adsorbents to remove different textile dyes from water. Selective adsorption of methylene blue (MB), methyl orange (MO), methyl violet (MV), and rhodamine B (RB) textile dyes on PTG and graphite waste/Fe₃O₄ composites were studied. The removal of dyes in water was assessed to evaluate the selectivity of PTG and graphite waste/Fe₃O₄ composites. The graphite/Fe₃O₄ (1:0.5), graphite/Fe₃O₄ (1:1), and graphite/Fe₃O₄ (1:2) composites based PTG is abbreviated GF1, GF2, and GF3, respectively, were prepared with different weights of Fe₃O₄ magnetic nanoparticles with ratio of 1:0.5, 1:1, and 1:2 (w/w%). The adsorption experiment was carried out in batch reactor with adsorbent dosage of 0.1 g and dye concentration of 10 mg/L. The results showed that the optimum adsorption capability of the PTG was 96.3, 89.2, 100, and 75.3 for MB, MO, MV, and RB, respectively. Under comparable experimental condition, the GF2 (2M HCl) showed the optimum removal of dyes of 81.6% (MB), 40.9% (MO), 76.0% (MV) and 20.9% (RB). The adsorption capacity of the dyes is governed by electrostatic interaction between the dyes and the functional groups on the adsorbent. The PTG and the GF2 (2M HCl) composite are promising candidates as low-cost adsorbents for removal of pollutive dyes from waste water.

The objective of this research was to synthesize of natural, pectin, and activated carbon from Kepok banana peels (Musa paradisiaca L). The use of raw banana peels as precursor for synthesis of adsorbent have significant advantages. Kepok banana peels were modified into three types of compounds with different physical and physicochemical treatments. Type 1 is natural, which is made by only thermal and physical treatment. Type 2 is pectin which was made by esterification reaction. Type 3 is activated carbon which was made by chemical activation using NaOH reagent for activation and carbonized at 400☐C. The yields of type 1, type 2 and type 3 are 11, 52 and 26%, respectively. FTIR characterization showed that type 1 and type 2 have the hydroxyl and carboxyl groups, while in type 3 has only carboxyl groups. Chemical treatment of dehydrated banana peels with acid (HCl) and alkali (NaOH) agents modified the surface morphological and fundamental physical properties of pectin and activated carbon. Types 1 – 3 are low cost potential adsorbent and these functional groups play major roles in adsorption.

In this research, zinc oxide based varistor are produce by using citrate-gel method compared to conventional solid-state method. The zinc oxide based varistor are fabricate using three different wt.% of ZnO-CaMnO₃-La₂O₃ and divided into three system which are 80 mol% ZnO + 20 mol% CaMnO₃, 79.5 mol% ZnO + 20 mol% CaMnO₃ + 0.5 mol% La₂O₃ and 78.5 mol% ZnO + 20 mol% CaMnO₃ + 1.5 mol% La₂O₃. ZnO-CaMnO₃-La₂O₃ compound experienced pre-sintering at 500 °C for 2 hours sintering time. In the sintering condition, sintering temperatures are manipulated, which are varied at 1100, 1200 and 1300 °C while, the sintering time is setting at 4.5 hours. X-ray diffraction patterns show this compound is high in crystallinity. The surface morphology with the average grains size between 2.0 ∼ 10.0 μm was observed by Scanning Electron Microscopy. Energy Dispersive Spectroscopy confirmed that distribution of element are homogenous with high purity. Density of the sample product is range between 5.0 ∼ 5.6 g cm⁻³. J-E characteristic shows the value of non-linearity coefficient in the range of 1.10 to 4.35.

Hydraulic ram pump (hydram) is a rather 'mature' technology as it has been used over the last two centuries with many variations in design and basic configurations have been tried. Pump motor is favoured rather than hydram to transfer the water from one point to another point because of its consistency. However, following the increasing awareness of the adverse impact of global warming and the needs of sustainable technology, interest in hydram for water supply purpose has revived. The purpose of this paper is to study the effectiveness of hydram implementation and the effect of the stroke valve design towards flow rate of water being delivered. There are three methods used in this study; (i) experimental evaluation of hydram; (ii) experimental evaluation of adjustable waste valve; and (iii) computational simulation of adjustable waste valve. The adjustable waste valve was designed, fabricated for experiment and modelled for simulation. The hydram is very good to be installed as a pump at hill because it can supply water more than high of inlet water. The different length of stroke shows different behaviour of water flow and more length of stroke, more flow rate of water at discharge pipe. Hydram has a great potential to be functioning as a simple and reliable pumping device in those hilly remote areas which are of no water supply coverage.

The purpose of this study was to investigate the mechanical and physical properties of chicken skin gelatin film as compared to mammalian gelatin films in terms of tensile strength (TS), elongation at break (EAB), puncture force, water vapour permeability (WVP), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), light barrier, thermal properties and microstructure. Three film formulations using 4g gelatin of three different types (chicken skin, bovine, and porcine gelatin) and 1.5g glycerol were prepared under mechanical stirring at a temperature of 45°C. The use of different types of gelatin resulted in different mechanical and physical properties. Results revealed that chicken skin gelatin film was optimal due to its high tensile strength (5.57 MPa) and low WVP (1.29 x 10⁻⁹ kPa) rate as compared to bovine and porcine gelatin films. The carboxyl group was revealed to be stronger in FTIR assay for chicken skin gelatin film, while XRD revealed amorphous characteristics at a peak 2Ɵ = 20°. These results contributed to its superior physical characteristics. These desirable characteristics mean that chicken skin gelatin film has remarkable potential as a biodegradable film material as compared to commercial gelatin. It may become a key preferred alternative for producing gelatin films for edible film purposes.

The intention of this research is to study effect of the different weight percent (wt%) of calcium nitrate, Ca(NO₃)₂ (CN) salt into biopolymer of Methylcellulose (MC). MC-CN solid biopolymer electrolyte was prepared by using casting technique. The concentrations of CN salt were prepared between 5 to 25 wt%. The optical and electrical characteristics of the samples were study by using Fourier Transform-Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD) and Electrical Impedance Spectroscopy (EIS). The highest conductivity of the samples was containing 25 wt% of CN is 2.21X10⁻⁷ Scm⁻¹. The optical study by using FTIR shows that the CN salt act as the conducting ions devoid of effect the molecular structure of the polymer. Additionally, the data of XRD revealed that MC-CN an amorphous phase.

This present study aims to analyze the functional group present in the Andrographis paniculata leaves or also known as kalmegh by using Shimadzhu Fourier Transform Infrared (FTIR) with the absorbance range of 500 cm⁻¹ - 4000 cm⁻¹. Andrographis paniculata (Nees) is a valuable traditional medicinal plant and it has many important bioactive compounds. In this study, kalmegh leaves powder was soaked in two different solvent which were 80% aqueous methanol and distilled water. After soaked for 24 hours, the soaked kalmegh leaves was extracted using rotary evaporator to get the crude extract before being subjected to Fourier Transform Infrared (FTIR) spectroscopy for characterization of functional group contains in the leaves. Results obtained from this present research show six major compound group which are alkene, amine, aromatic, nitro, and alcohol. This six functional group were identified from various wavenumber of bending and stretching type of alkene group (894.97 cm⁻¹ and 1645.10 cm⁻¹), stretching type of amine (1080.11 cm⁻¹), stretching type of aromatic group (1409.96 cm ⁻¹), stretching type of nitro group (1543.05 cm⁻¹), stretching type of alcohol group (3323.35 cm⁻¹) and phenol group (3749.62 cm⁻¹). This study attempts to display the use of FTIR while simultaneously creating interest among related researchers in natural plant analysis.

In this study, Zn₂SiO₄ composite-based ceramic was synthesised using amorphous SiO₂ nanoparticles as a silicon source. The amorphous SiO₂ nanoparticles which obtained from a simple precipitation process were mixed with aqueous zinc nitrate. Amorphous SiO₂ nanoparticles were encapsulated by the zinc source in aqueous solution, dried, and subjected to calcination. The underwent calcination showed the changing of phases, morphology, and size with increased temperatures. During calcination, ZnO phase appeared at the beginning of heating temperature and Zn₂SiO₄ phase started to emerge at 800 °C onwards, as shown by XRD patterns. The optical band gap analysis of Zn1₂SiO₄ composite was determined to be within the range of 3.12 to 3.19 eV. The diffusion of zinc ions into SiO₂ nanoparticles with high surface area also reduced the phase formation temperature for Zn₂SiO₄, compared to a conventional solid state method. This optical characteristic is expected to be a potential candidate for phosphor materials in opto-electronic devices application.

Zinc oxide (ZnO) varistors is a solid state electronic ceramic component whose function to protect electronic devices against over voltage surges due to their highly nonlinear electrical properties and ability in controlling the energy. In this study, ZnO varistor is prepared via solid state reaction method. The ZnO based varistor ceramics undergoes sintering temperature at 900 °C, 1100 °C and 1300 °C for 45 minutes. The used of sintering temperature from 900 to 1300 °C, has increased the grain size of ZnO and improved their crystallinity as shown from the peaks intensity of X-ray diffraction (XRD). Current-Voltage properties exhibit the value of nonlinear coefficient in the range of 1.44 to 1.76. Different sintering temperature is used to adjust the microstructure and improve the varistor ceramic characteristics where it shows a potential difference in various application of electronic devices. Increasing in sintering temperature would lead to improved grain growth for better electrical properties.

Cellulose derivatives have high potential for use as solid biopolymer electrolytes in proton batteries because they are biodegradable, affordable, have good mechanical properties and their ionic conductivity can be enhanced with addition of ionic dopant. In this work, we developed a new type of solid biopolymer electrolytes (SBEs) based on 2-hydroxyethyl cellulose (2HEC) doped with glycolic acid (GA) as an ionic dopant. A solution casting technique was used to prepare the SBEs. The ionic conductivity and structural properties of the SBEs were analysed using Electrical Impedance Spectroscopy (EIS), Fourier Transform Infrared spectroscopy (FTIR) and an X-ray Diffractometer (XRD). The highest ionic conductivity achieved was 3.80 x10⁻⁴ S cm⁻¹ for the sample with 40 wt.% GA concentration at room temperature. FT-IR analysis showed that complexation occurred in the polymer system from the shifting of υC-O and υ_sCOO^- band of 2HEC and GA. FTIR deconvolution revealed the increasing pattern of percentage free mobile ions with the addition of GA concentration until 40 wt.% GA, which can be related to the high ionic conductivity of the sample. In XRD analysis, all SBEs shows amorphous nature. Based on the results obtained, GA is a good ionic dopant because it succeed in improve the ionic conductivity of the 2HEC film.

This present work discussed the ionic conductivity and ionic conduction mechanism of solid polymer electrolyte (SPE). The SPE was prepared from 2-hydroxyethyl cellulose incorporated with ammonium nitrate and plasticized with ethylene carbonate (2-HEC-AN-EC) via well-known solution casting method. All SPEs were characterized using electrical impedance spectroscopy (EIS). It was found that the ionic conductivity at elevated temperature obeys Arrhenius rule. The plot of frequency exponent s against temperature shows that the correlated barrier hopping (CBH) was the best model to explain the ion conduction through 2-HEC-AN-EC SPE.

The rapid development of wireless technology nowadays has led to the increases of erection of base station telecommunication (BST). However, the exposure transmitted from BST generated the public concern on health problem because it is said can causes high risk to the human and surroundings. Therefore, this study will focused on the influence of selected BST installed around Kuala Nerus towards the ambient NIR exposure value at surroundings. By using spectrum analyzer connected to receiving omni-directional antenna, the NIR exposure level in terms of electric field (EF) strength is measured horizontally at 50 m until 500 m around the BSTs. The comparison between the measured values and the international reference levels of ICNIRP were done. Besides, the exposure values were compared among the BSTs area by considering the other influenced factors at surroundings. The result shows that the highest exposure level was recorded at BST located in sub-urban area and has the higher number of antennas installed on the top. It can be concluded that the number of BST nearby, the number of antennas, the direction of the antenna and the presence of other sources influenced the ambient NIR exposure at that area.

The interference occurs in radio signals transmission in many communication technologies are attributed to weather variations as well as other environmental factors. This work evaluates some atmospheric variables that have a dominating impact on temporal signal strength fluctuations. The Received Power Level (RPL) of Ultra High Frequency (UHF) communication signals (1800 MHz and 2160 MHz) and three tropical weather predictors (humidity, temperature and wind) were collected using spectrum analyser (KEYSIGHT N9915A) and weather station (Vantage Pro 2) respectively for 24 hours in rainy days. SmartPLS 3.2.6 was used to determine the strongest predictors influence the RPL for UHF frequency. It has been found that changes in weather conditions have affected the signal in which all weather predictors provide a significant relationship to the signal where R² (coefficient of determination) value is 0.314 for frequency 1800 MHz and 0.254 for frequency 2160 MHz. The findings also show that humidity, temperature and wind are anticorrelations to RPL. However, humidity is found to be the strongest predictor influences the RPL of communication signals for frequency 1800 MHz (β = −0.449, p = 0.000). This model may benefit many sectors such as telecommunication service provider, radio and TV transmission, radio astronomy study, Electromagnetic (EM) researcher and satellite broadcasting.

In 3D bioprinting system, there are varies set of printing parameter involved that will affect the structure of bioprinted construct and cell viability. This study reports the effect of extrusion pressure and printing speed on the structure of construct and cell viability. This study contains two parts which first, to see the effect of the morphological structure of the construct by printing using Pluronic F127 and second, too evaluate the viability of the cell on the bioprinted construct by printing using fibroblast cell-laden Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) and Gelatin Methacrylate (GelMa). The construct was printed by using extrusion based 3D bioprinter with various ranges of extrusion pressure and printing speed. Based on the experiment, the result shows that printing at lower extrusion pressure requires a lower printing speed whereas printing at higher extrusion pressure requires a higher printing speed. For the cell viability of the bioprinted construct, printing at higher extrusion pressure will reduce the percentage of cell viability.

Recent years have witnessed a huge growth of research in pharmaceutical sciences using nanoparticles as drug transport to reduce toxicity and for more specific drug targeting. Conventional application of drugs has major limitation and drawback since they have limited effectiveness, unsustainable release, and poor biodistribution. Thus this paper aims to produce a suitable material loaded with drugs that can provide an efficient effect of the drug at the site of action and maintain them throughout the treatment. Halloysite nanotubes were used as the material since it fulfills all the criteria needed for sustained drug release. Here, benzalkonium chloride was used as an antiseptic along with methylene blue and methyl orange as the cationic and anionic drug models. All three drugs were loaded into the halloysite lumen by vacuum suction. Result shows the most successful loading efficiency is halloysite loaded with methyl orange where the loading is almost 82% and also shows an excellent sustained release for 19 hours when released in 0.3M hydrochloric acid.

Microbial cellulose (MC) is a type of polysaccharide that has high purity properties, which can be produced by different types of microorganism such as Pseudomonas, Komagataeibacter, Sarcina and Azotobacter and widely used in industrial applications. However, the main drawback in microbial cellulose production is low yield, which unable to meet the requirements of the industry. This study aims to determine the effects of different nitrogen sources combinations on microbial cellulose production by Pseudomonas aeruginosa and to maximize microbial cellulose production using the best nitrogen sources combination. To improve cellulose production, five different nitrogen sources combinations, which were yeast extract (YE) + (NH₄)₂SO₄, YE + NH₄NO₃, YE + urea, YE + tryptic soy broth and YE + beef extract were added into the media with the composition of 50 g/L glucose, 3/L g KH₂PO₄ and 0.05 g/L MgSO₄. The batch fermentation was done in incubator shaker with 150 rpm at 30°C for five days. The samples were harvested every 24 hours, centrifuged, purified and dried for microbial cellulose concentration determination. The results obtained indicated that YE and beef extract combination produced the highest microbial cellulose concentration of 1.7 g/L. To attain the second objective, optimization study was carried out by using different concentrations, which were 5 g/L, 10 g/L, 15 g/L and 20 g/L of YE and beef extract combination. An investigation using 10 g/L YE and beef extract has produced 1.7 g/L of microbial cellulose, which proved to be the potential enhancer for microbial cellulose synthesis. It is recommended that additional morphology analyses should be done to investigate the influence of fermentation conditions and low-cost nitrogen sources media components on microbial cellulose morphology and its mechanical properties. This will help to synthesize desired and reliable microbial cellulose pellicles.

For ages, natural psychedelic resources have been used by ancient tribes for religious inspiration. In modern medicine, these compounds were prescribed to relieve severe distress and depression on cancer patients. Despite medical benefit, abuse of these compounds have become prevalent in our modern society. These compounds usually interacted with cannabinoid receptor 1 (CNR1) on neuron cell causing hallucination, and on other cell-types. In this study, chemically synthesized terphenyl derivative, 1,4-di(phenyl)benzene (13-BPB) interaction with human and its animal model were assessed. This derivative is an analogue found in fungi although their functional molecular mechanism is unknown. Terphenyl derivative known to have pharmacological activities - antifungal, anti-cancer, anticoagulant. Our study designed includes in-vitro assessment and in-silico model of 13-BPB interaction to the molecular mechanism in human and its animal model, mice. Cytotoxicity assessment using MTT has shown that treatment of 13BPB on NIH-3T3 and RAW 264.7 have significant reduction in cell viability at 0.016mM and 0.08mM, respectively. Virtual database screening based on homologous compounds identified possible interaction with 15 different proteins from receptors, enzymes and transcription factors, in human and mice. Further docking analysis shows terphenyl derivatives binding affinities (pKd/pKi) are the highest with CNR1 and oestrogen receptors (ESRs).

Cryptocoryne elliptica is a Malaysia endogenous aquatic plants that has been categorized as endangered species. The plant received a highly demand for aquarium trade and being collected from wild. Slow growth and propagates only through runners has obstructs the plantlets production. Micro propagation is the best option. However, study on the effects of cytokinin particularly thidiazuron (TDZ) on the proliferation rate of this plant in vitro is still limited. Thus, the objective of this study was to determine the effects of thidiazuron on multiple shoots proliferation under in vitro conditions. A complete randomized design was used. TDZ was tested at the concentrations of 0.2 − 1.0 mg/l in two media: Murashige and Skoog (MS) and Linsmaier and Skoog (LS), respectively. Single shoot explant was used for each culture vessel with thirty cultures per-treatment. Results showed that the highest shoots number generated per explant was obtained in MS + 0.8 mg/l TDZ, which was 7.33 ± 3.08 after 8 weeks of cultures. The protocorm-like-bodies (PLBs) were produced in MS + 0.4 − 0.8 mg/l TDZ and LS + 0.2 − 1.0 mg/l TDZ, after 28 weeks of culture, respectively. The inflorescences were also formed on the explants cultured on TDZ containing medium. This finding suggested that TDZ had alters the proliferation and differentiation on C. elliptica cells.

Honey composition could change during storage, which might affect the quality of honey. Subsequently, it could reduce the honey commercial value. However, data on the effect of the storage on several types of local honey is still lacking. Thus, in this study, moisture content, pH and antioxidant level of honey stored at 4°C were analysed after six-month of the storage. Initially, physicochemical properties (moisture, electrical conductivity, ash content, pH, free acidity and hydroxymethylfurfural (HMF) level) and antioxidant levels of five local honey samples (Tualang, Gelam, Pineapple, Acacia and Kelulut honey) and Manuka honey as a control were determined. Afterwards, honey samples were stored at 4°C for six months and their moisture content, pH and antioxidant levels were monitored monthly. Physicochemical properties were measured based on the standard method set by the International Honey Commission (IHC). Antioxidant activity was determined based on previous studies. Most of the honey samples exhibited physicochemical properties within the range set by the Codex Standard for Honey but displayed lower antioxidant level compared to other studies. On average, honey moisture content increased by 0.1 to 0.4% while their antioxidant level increased by 2.6 mg GAE/kg to 6.3 mg GAE/kg monthly. In contrast, pH level of honey decreased by 0.03 to 0.09 monthly. Storage of honey at low temperature increases its moisture and antioxidant level while decreases its pH level. However, further study needs to be carried out to observe whether the pattern will continue even after a lengthy storage period exceeding six months.

Stingless bees (Kelulut) can produce three major commercial products i.e. honey, propolis and beebread. These products are widely believed to have medicinal benefits, similar with products produced by stinging bees. However, there are very few scientific data available on the stingless bee's products to prove the claims. Thus, this study was conducted to investigate the characteristics of the products from the perspective of physicochemical analysis, activities of antioxidant and anti proliferation on cancer cells. Stingless bees honey, propolis and beebread were collected and their physicochemical and antioxidant properties were analysed prior to treatment on human breast adenocarcinoma (MCF-7) cell lines. Physicochemical analysis indicated that the samples are mostly not within the range reported by the Codex Standard for Honey. Honey, propolis and beebread exhibited antioxidant activity through the total phenolic content of 700 mg GAE/kg, 1600 mg GAE/kg and 300 mg GAE/kg respectively. Propolis has the highest antioxidant activity and inhibited MCF-7 cell growth at IC₅₀ of 38.9 μg/ml. Meanwhile, stingless bee honey and beebread displayed the IC₅₀ at 60 v/v and 64μg/mL respectively. The data is crucial to unveiled and prove medicinal properties and potential possessed by the stingless bee products. Subsequently, increase their commercial value in the future.

Physicochemical analysis is one of the methods used to measure the quality and authenticity of honey. Quality and authenticity of honey are crucial to ensure only a high quality of natural honey is offered to consumers and to avoid any health complications in the future. However, relatively few physicochemical data is available on the Malaysian honey. In this study, selected physicochemical analyses were conducted on several local honey. Seven honey samples i.e. Tualang honey, Rubber honey, Acacia honey, Kelulut 1 honey, Kelulut 2 honey, adulterated honey 1 and adulterated honey 2 were used and their physicochemical properties measured. Natural honey samples exhibited varying physicochemical characteristics compared to adulterated honey. The adulterated honey 1 had the highest HMF level (164.55 ± 27.14mg/kg), with a low level of pH (3.2 ± 0.02), free acidity (20.8 ± 0.17) and electrical conductivity (0.003 ± 0.00) compared to the natural honey. These preliminary data could serve as a basis for the identification and characterisation of Malaysian honey based on the physicochemical analysis. Moreover, the data can support enforcement activities by the authorities in preventing adulterated honey production and trading in the future.

Obesity is one of major health problems occurred worldwide including Malaysia. Unfortunately, no suitable treatment or mechanism can be used to solve the problem effectively. In order to find the most appropriate treatment, stevioside was chosen to investigate its effects in preventing obesity. Stevioside was used to observe its effect in four stages of differentiation process (lipid formation) 3T3-L1 murine pre-adipocytes (fibroblasts) into adipocytes. The process was observed using Oil red-O staining and measured using a spectrophotometer at the wavelength of 520 nm. From the results, stevioside was significantly inhibited the differentiation process at stage 2. Stevioside may interfere with the other supplements added in the cell culture media, which triggered the inhibition. However, the mechanism was unclear and required further studies.