MyMedR

Displaying publications 1 - 20 of 25 in total

Abstract:

Sort:

Environmental degradation of microbial polyhydroxyalkanoates and oil palm-based composites

Salim YS, Sharon A, Vigneswari S, Mohamad Ibrahim MN, Amirul AA

Appl Biochem Biotechnol, 2012 May;167(2):314-26.
PMID: 22544728 DOI: 10.1007/s12010-012-9688-6

This paper investigates the degradation of polyhydroxyalkanoates and its biofiber composites in both soil and lake environment. Time-dependent changes in the weight loss of films were monitored. The rate of degradation of poly(3-hydroxybutyrate) [P(3HB)], poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-23 mol% 4HB)] and poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-9 mol% 3HV-co-19 mol% 4HB)] were investigated. The rate of degradation in the lake is higher compared to that in the soil. The highest rate of degradation in lake environment (15.6% w/w week(-1)) was observed with P(3HB-co-3HV-co-4HB) terpolymer. Additionally, the rate of degradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-38 mol% 3HV)] was compared to PHBV biofiber composites containing compatibilizers and empty fruit bunch (EFB). Here, composites with 30% EFB displayed the highest rate of degradation both in the lake (25.6% w/w week(-1)) and soil (15.6% w/w week(-1)) environment.
Effect of enzymatic interesterification on melting point of palm olein

Yassin AA, Mohamed IO, Ibrahim MN, Yusoff MS

Appl Biochem Biotechnol, 2003 Jul;110(1):45-52.
PMID: 12909731

Immobilized PS-C 'Amano' II lipase was used to catalyze the interesterification of palm olein (POo) with 30, 50, and 70% stearic acid in n-hexane at 60 degrees C. The catalytic performance of the immobilized lipase was evaluated by determining the composition change of fatty acyl groups and triacylglycerol (TAG) by gas liquid chromatography and high-performance liquid chromatography, respectively. The interesterification process resulted in the formation of new TAGs, mainly tripalmitin and dipalmitostearin, both of which were absent in the original oil. These changes in TAG composition resulted in an increase in slip melting point, from the original 25.5 degrees C to 36.3, 37.0, and 40.0 degrees C in the modified POo with 30, 50, and 70% stearic acid, respectively. All the reactions attained steady state in about 6 h. This type of work will find great applications in food industries, such as confectionery.
Fulltext Spectrophotometric Analysis of Caffeine

Ahmad Bhawani S, Fong SS, Mohamad Ibrahim MN

Int J Anal Chem, 2015;2015:170239.
PMID: 26604926 DOI: 10.1155/2015/170239

The nature of caffeine reveals that it is a bitter white crystalline alkaloid. It is a common ingredient in a variety of drinks (soft and energy drinks) and is also used in combination with various medicines. In order to maintain the optimum level of caffeine, various spectrophotometric methods have been developed. The monitoring of caffeine is very important aspect because of its consumption in higher doses that can lead to various physiological disorders. This paper incorporates various spectrophotometric methods used in the analysis of caffeine in various environmental samples such as pharmaceuticals, soft and energy drinks, tea, and coffee. A range of spectrophotometric methodologies including chemometric techniques and derivatization of spectra have been used to analyse the caffeine.
Editorial: Design and Synthesis of Metallic Nanoparticles for Targeted Therapy and Diagnostics

Umar S, Mohamad Ibrahim MN, Umar K, Ahmad N

Front Chem, 2020;8:597800.
PMID: 33304886 DOI: 10.3389/fchem.2020.597800
Fulltext Scavenging of caffeine from aqueous medium through optimized H3PO4-activated Acacia mangium wood activated carbon: Statistical data of optimization

Danish M, Birnbach J, Mohamad Ibrahim MN, Hashim R

Data Brief, 2020 Feb;28:105045.
PMID: 31921950 DOI: 10.1016/j.dib.2019.105045

The optimization data presented here are part of the study planned to remove the caffeine from aqueous solution through the large surface area optimized H3PO4-activated Acacia mangium wood activated carbon (OAMW-AC). The maximum adsorption capacity of the OAMW-AC for caffeine adsorption was achieved (30.3 mg/g) through optimized independent variables such as, OAMW-AC dosage (3.0 g/L), initial caffeine concentration (100 mg/L), contact time (60 min), and solution pH (7.7). The adsorption capacity of OAMW-AC was optimized with the help of rotatable central composite design of response surface methodology. Under the stated optimized conditions for maximum adsorption capacity, the removal efficiency was calculated to be 93%. The statistical significance of the data set was tested through the analysis of variance (ANOVA) study. Data confirmed the statistical model for caffeine adsorption was significant. The regression coefficient (R2) of curve fitting through the quadratic model was found to be 0.9832, and the adjusted regression coefficient was observed to be 0.9675.
UPLC method for the determination of vitamin E homologues and derivatives in vegetable oils, margarines and supplement capsules using pentafluorophenyl column

Wong YF, Makahleh A, Saad B, Ibrahim MN, Rahim AA, Brosse N

Talanta, 2014 Dec;130:299-306.
PMID: 25159413 DOI: 10.1016/j.talanta.2014.07.021

A sensitive and rapid reversed-phase ultra performance liquid chromatographic (UPLC) method for the simultaneous determination of tocopherols (α-, β-, γ-, δ-), tocotrienols (α-, β-, γ-, δ-), α-tocopherol acetate and α-tocopherol nicotinate is described. The separation was achieved using a Kinetex pentafluorophenyl (PFP) column (150 × 2.1mm, 2.6 µm) with both photodiode array (PDA) and fluorescence (FL) detectors that were connected in series. Column was thermostated at 42°C. Under a gradient system consisting of methanol and water at a constant flow rate of 0.38 mL min(-1), all the ten analytes were well separated in less than 9.5 min. The method was validated in terms of linearity, limits of detection and quantitation, precision and recoveries. Calibration curves of the ten compounds were well correlated (r(2)>0.999) within the range of 100 to 25,000 μg L(-1) for α-tocopherol acetate and α-tocopherol nicotinate, 10 to 25,000 μg L(-1) for α-tocotrienol and 5 to 25,000 μg L(-1) for the other components. The method is simple and sensitive with detection limits (S/N, 3) of 1.0 to 3.0 μg L(-1) (FL detection) and 30 to 74 μg L(-1) (PDA detection). Relative standard deviations for intra- and inter-day retention times (<1%) and peak areas (≤ 4%) were obtained. The method was successfully applied to the determination of vitamin E in vegetable oils (extra virgin olive, virgin olive, pomace olive, blended virgin and refined olive, sunflower, soybean, palm olein, carotino, crude palm, walnut, rice bran and grape seed), margarines and supplements.
Fulltext Mapping of mosquito breeding sites in malaria endemic areas in Pos Lenjang, Kuala Lipis, Pahang, Malaysia

Ahmad R, Ali WN, Nor ZM, Ismail Z, Hadi AA, Ibrahim MN, et al.

Malar J, 2011;10:361.
PMID: 22166101 DOI: 10.1186/1475-2875-10-361

The application of the Geographic Information Systems (GIS) to the study of vector transmitted diseases considerably improves the management of the information obtained from the field survey and facilitates the study of the distribution patterns of the vector species.
A novel agricultural waste adsorbent for the removal of lead (II) ions from aqueous solutions

Ibrahim MN, Ngah WS, Norliyana MS, Daud WR, Rafatullah M, Sulaiman O, et al.

J Hazard Mater, 2010 Oct 15;182(1-3):377-85.
PMID: 20619537 DOI: 10.1016/j.jhazmat.2010.06.044

The present study explores the ability of modified soda lignin (MSL) extracted from oil palm empty fruit bunches (EFB) in removing lead (II) ions from aqueous solutions. The effect of contact time, point zero charge (pH(pzc)) and pH of the solution, initial metal ion concentration and adsorbent dosage on the removal process were investigated. Furthermore, the MSL is characterized by SEM, XRF, FT-IR and surface area analysis. Equilibrium adsorption isotherms and kinetics were investigated. The experimental data were analyzed by the Langmuir, Freundlich and Temkin models of adsorption. The kinetic data obtained at different initial concentrations were analyzed using pseudo-first-order and pseudo-second-order models. The results provide strong evidence to support the hypothesis of adsorption mechanism.
Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and characterisation of its blend with oil palm empty fruit bunch fibers

Salim YS, Abdullah AA, Nasri CS, Ibrahim MN

Bioresour Technol, 2011 Feb;102(3):3626-8.
PMID: 21115240 DOI: 10.1016/j.biortech.2010.11.020

Poly(3-hydroxybutyrate-co-38 mol%-3-hydroxyvalerate) [P(3HB-co-38mol%-3HV)] was produced by Cupriavidus sp. USMAA2-4 in the presence of oleic acid and 1-pentanol. Due to enormous production of empty fruit bunch (EFB) in the oil palm plantation and high production cost of P(3HB-co-3HV), oil palm EFB fibers were used for biocomposites preparation. In this study, maleic anhydride (MA) and benzoyl peroxide (DBPO) were used to improve the miscibility between P(3HB-co-3HV) and EFB fibers. Introduction of MA into P(3HB-co-3HV) backbone reduced the molecular weight and improved the thermal stability of P(3HB-co-3HV). Thermal stability of P(3HB-co-3HV)/EFB composites was shown to be comparable to that of commercial packaging product. Composites with 35% EFB fibers content have the highest tensile strength compared to 30% and 40%. P(3HB-co-3HV)/EFB blends showed less chemicals leached compared to commercial packaging.
Fulltext Image reconstruction of a charge coupled device based optical tomographic instrumentation system for particle sizing

Idroas M, Rahim RA, Green RG, Ibrahim MN, Rahiman MH

Sensors (Basel), 2010;10(10):9512-28.
PMID: 22163423 DOI: 10.3390/s101009512

This research investigates the use of charge coupled device (abbreviated as CCD) linear image sensors in an optical tomographic instrumentation system used for sizing particles. The measurement system, consisting of four CCD linear image sensors are configured around an octagonal shaped flow pipe for a four projections system is explained. The four linear image sensors provide 2,048 pixel imaging with a pixel size of 14 micron × 14 micron, hence constituting a high-resolution system. Image reconstruction for a four-projection optical tomography system is also discussed, where a simple optical model is used to relate attenuation due to variations in optical density, [R], within the measurement section. Expressed in matrix form this represents the forward problem in tomography [S] [R] = [M]. In practice, measurements [M] are used to estimate the optical density distribution by solving the inverse problem [R] = [S](-1)[M]. Direct inversion of the sensitivity matrix, [S], is not possible and two approximations are considered and compared-the transpose and the pseudo inverse sensitivity matrices.
Utilization of lignocellulosic biomass: A practical journey towards the development of emulsifying agent

Safian MT, Sekeri SH, Yaqoob AA, Serrà A, Jamudin MD, Mohamad Ibrahim MN

Talanta, 2022 Mar 01;239:123109.
PMID: 34864531 DOI: 10.1016/j.talanta.2021.123109

With each passing year, the agriculture and wood processing industries generate increasingly high tonnages of biomass waste, which instead of being burned or left to accumulate should be utilized more sustainably. In parallel, advances in green technology have encouraged large companies and nations to begin using eco-friendly materials, including eco-friendly emulsifiers, which are used in various industries and in bio-based materials. The emulsion-conducive properties of lignocellulosic materials such as cellulose, hemicellulose, and lignin, the building blocks of plant and wood structures, have demonstrated a particular ability to alter the landscape of emulsion technology. Beyond that, the further modification of their structure may improve emulsion stability, which often determines the performance of emulsions. Considering those trends, this review examines the performance of lignocellulosic materials after modification according to their stability, droplet size, and distribution by size, all of which suggest their outstanding potential as materials for emulsifying agents.
Fulltext Mechanical property and quality aspects of rice dried in industrial dryers

Sarker MSH, Hasan SMK, Ibrahim MN, Aziz NA, Punan MS

J Food Sci Technol, 2017 Nov;54(12):4129-4134.
PMID: 29085156 DOI: 10.1007/s13197-017-2856-5

The influence of drying methods on selected mechanical properties and qualities of MR219 rice variety has been investigated. The results showed significant effects of drying methods on bending strength and head rice yields while the average bending strength of paddy were 28.6-31.8 MPa. The effect of drying methods on apparent modulus of elasticity of rice was not significant (204.5-222.4 MPa). The fracture energy of rice varied significantly under control drying but not with industrial drying methods. Higher temperature in drying by IBD contributed in making the grains tougher, where the effect of FBD temperature was positive toward the development of fracture energy inside rice kernel. IBD at temperature above 40 °C resulted in lower bending strength in rice kernels which affected head rice yield. Two stage paddy drying practices with FBD using temperature of 115-125 °C as first stage is still acceptable, and inclined bed dryer either as single stage or as second stage after FBD should be operated at temperature of <40 °C to maintain head rice yield. The whiteness and milling recovery of rice achieved from different drying methods were comparable.
Development and Standardization of Moringa oleifera Leaves as a Natural Dietary Supplement

Ali MA, Yusof YA, Chin NL, Ibrahim MN, Muneer S

J Diet Suppl, 2019;16(1):66-85.
PMID: 29469600 DOI: 10.1080/19390211.2018.1429517

Moringa oleifera leaves were selected as a model due to their hundreds of health benefits. On the other hand, the powder of these leaves has exhibited poor flowability, low tensile strength, bitter taste, poor dissolution rate, and lack of information regarding dosage. These are the common hurdles and limitations in the adaptation of herbal-based medications. Therefore, a comprehensive study was planned to introduce herbal-based medicines into mainstream medicines by standardization according to the U.S. Food and Drug Administration (FDA) and international pharmaceutical standards. A Simplex Lattice Design (SLD) of Design Expert 8.0 software was used to formulate different concentrations of superdisintegrant, binder/diluent, and sweeteners. An Instron Universal Testing machine coupled with a 13 mm stainless cylindrical die was used to manufacture tablets by means of direct compression method at 20 kN applied force. Therefore, selection of excipients was made on the basis of their tensile strength, flowability, and taste-masking properties. Optimum formulation was tested on rabbits for toxicity and growth rate. All formulated tablets were evaluated on standard parameters for orally disintegrating tablets described by the Food and Drug Authority (U.S.). The optimum formulation fulfills all standard parameters such as hardness, disintegration time, friability, and dissolution rate. The present formulation showed no toxicity when tested on rabbits. The present study provides a fundamental understanding of the tableting characteristics of natural medicines. The present study provides information that will help to overcome the challenges.
The use of date palm as a potential adsorbent for wastewater treatment: a review

Ahmad T, Danish M, Rafatullah M, Ghazali A, Sulaiman O, Hashim R, et al.

Environ Sci Pollut Res Int, 2012 Jun;19(5):1464-84.
PMID: 22207239 DOI: 10.1007/s11356-011-0709-8

BACKGROUND: In tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution.
REVIEW: This article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years.
CONCLUSION: Studies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.
Fulltext Synthesis, Characterization, and Photocatalytic Activities of Graphene Oxide/metal Oxides Nanocomposites: A Review

Jamjoum HAA, Umar K, Adnan R, Razali MR, Mohamad Ibrahim MN

Front Chem, 2021;9:752276.
PMID: 34621725 DOI: 10.3389/fchem.2021.752276

Sustainable water processing techniques have been extensively investigated and are capable of improving water quality. Among the techniques, photocatalytic technology has shown great potential in recent years as a low cost, environmentally friendly and sustainable technology. However, the major challenge in the industrial development of photocatalyst technology is to develop an ideal photocatalyst which must have high photocatalytic activity, a large specific surface area, harvest sunlight and shows recyclability. Keeping these views, the present review highlighted the synthesis approaches of graphene/metal oxide nanocomposite, characterization techniques and their prominent applications in photocatalysis. Various parameters such as photocatalyst loading, structure of photocatalyst, temperature, pH, effect of oxidizing species and wavelength of light were addressed which could affect the rate of degradation. Moreover, the formation of intermediates during photo-oxidation of organic pollutants using these photocatalysts is also discussed. The analysis concluded with a synopsis of the importance of graphene-based materials in pollutant removal. Finally, a brief overview of the problems and future approaches in the field is also presented.
Fulltext Surfactant modified/mediated thin-layer chromatographic systems for the analysis of amino acids

Bhawani SA, Albishri HM, Khan ZA, Mohamad Ibrahim MN, Mohammad A

J Anal Methods Chem, 2013;2013:973280.
PMID: 24455427 DOI: 10.1155/2013/973280

This review incorporates a large number of chromatographic systems modified by the surfactants. A large number of solvent systems and stationary phases are summarized in this paper. Three different kinds of surfactants (anionic, cationic, and nonionic) are used as modifiers for stationary phases as well as solvent systems. Surfactants are used at all the three different concentration levels (below, above, and at critical micelle concentration) where surfactants behave differently. Modifications of both stationary phases and solvent systems by surfactants produced a new generation of chromatographic systems. Microemulsion solvent systems are also incorporated in this paper. Microemulsion thin-layer chromatography is a new approach in the field of chromatography.
Fulltext Advancement in Benthic Microbial Fuel Cells toward Sustainable Bioremediation and Renewable Energy Production

Umar MF, Rafatullah M, Abbas SZ, Mohamad Ibrahim MN, Ismail N

Int J Environ Res Public Health, 2021 Apr 06;18(7).
PMID: 33917378 DOI: 10.3390/ijerph18073811

Anthropogenic activities are largely responsible for the vast amounts of pollutants such as polycyclic aromatic hydrocarbons, cyanides, phenols, metal derivatives, sulphides, and other chemicals in wastewater. The excess benzene, toluene and xylene (BTX) can cause severe toxicity to living organisms in wastewater. A novel approach to mitigate this problem is the benthic microbial fuel cell (BMFC) setup to produce renewable energy and bio-remediate wastewater aromatic hydrocarbons. Several mechanisms of electrogens have been utilized for the bioremediation of BTX through BMFCs. In the future, BMFCs may be significant for chemical and petrochemical industry wastewater treatment. The distinct factors are considered to evaluate the performance of BMFCs, such as pollutant removal efficiency, power density, and current density, which are discussed by using operating parameters such as, pH, temperature and internal resistance. To further upgrade the BMFC technology, this review summarizes prototype electrode materials, the bioremediation of BTX, and their applications.
Fulltext Aural myiasis in a neonate in peninsular Malaysia

Ahmad NW, Ismail A, Jeffery J, Ibrahim S, Hadi AA, Ibrahim MN, et al.

Parasit Vectors, 2009;2(1):63.
PMID: 20003466 DOI: 10.1186/1756-3305-2-63

Myiasis is a pathological condition in humans and animals caused by various species of dipterous larvae. Myiasis which occurs in a newborn baby is referred as neonatal myiasis. It is a rare condition and there are only a few reports to date. A case of neonatal aural myiasis in a two day old infant is reported in this paper.
Environmental variables associated with immature stage habitats of culicidae collected in aboriginal villages in Pahang, Malaysia

Ali WN, Ahmad R, Nor ZM, Ismail Z, Ibrahim MN, Hadi AA, et al.

Southeast Asian J. Trop. Med. Public Health, 2012 Nov;43(6):1387-99.
PMID: 23413702

Many of the most widely spread vector-borne diseases are water related, in that the mosquito vectors concerned breed or pass part of their lifecycle in or close to water. A major reason for the study of mosquito larval ecology is to gather information on environmental variables that may determine the species of mosquitoes and the distribution of larvae in the breeding habitats. Larval surveillance studies were conducted six times between May 2008 and October 2009 in Pos Lenjang, Kuala Lipis, Pahang. Twelve environmental variables were recorded for each sampling site, and samples of mosquito larvae were collected. Larval survey studies showed that anopheline and culicine larvae were collected from 79 and 67 breeding sites, respectively. All breeding sites were classified into nine habitat groups. Culicine larvae were found in all habitat groups, suggesting that they are very versatile and highly adaptable to different types of environment. Rock pools or water pockets with clear water formed on the bank of rivers and waterfalls were the most common habitats associated with An. maculatus. Environmental variables influence the suitability of aquatic habitats for anopheline and culicine larvae, but not significantly associated with the occurrence of both larvae genera (p>0.05). This study provides information on mosquito ecology in relation to breeding habitats that will be useful in designing and implementing larval control operations.
Insights into the Current Trends in the Utilization of Bacteria for Microbially Induced Calcium Carbonate Precipitation

Chuo SC, Mohamed SF, Mohd Setapar SH, Ahmad A, Jawaid M, Wani WA, et al.

Materials (Basel), 2020 Nov 05;13(21).
PMID: 33167607 DOI: 10.3390/ma13214993

Nowadays, microbially induced calcium carbonate precipitation (MICP) has received great attention for its potential in construction and geotechnical applications. This technique has been used in biocementation of sand, consolidation of soil, production of self-healing concrete or mortar, and removal of heavy metal ions from water. The products of MICP often have enhanced strength, durability, and self-healing ability. Utilization of the MICP technique can also increase sustainability, especially in the construction industry where a huge portion of the materials used is not sustainable. The presence of bacteria is essential for MICP to occur. Bacteria promote the conversion of suitable compounds into carbonate ions, change the microenvironment to favor precipitation of calcium carbonate, and act as precipitation sites for calcium carbonate crystals. Many bacteria have been discovered and tested for MICP potential. This paper reviews the bacteria used for MICP in some of the most recent studies. Bacteria that can cause MICP include ureolytic bacteria, non-ureolytic bacteria, cyanobacteria, nitrate reducing bacteria, and sulfate reducing bacteria. The most studied bacterium for MICP over the years is Sporosarcina pasteurii. Other bacteria from Bacillus species are also frequently investigated. Several factors that affect MICP performance are bacterial strain, bacterial concentration, nutrient concentration, calcium source concentration, addition of other substances, and methods to distribute bacteria. Several suggestions for future studies such as CO2 sequestration through MICP, cost reduction by using plant or animal wastes as media, and genetic modification of bacteria to enhance MICP have been put forward.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links