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  1. Fulltext Characterization of detergent compatible protease from halophilic Virgibacillus sp. CD6
    Lam MQ, Nik Mut NN, Thevarajoo S, Chen SJ, Selvaratnam C, Hussin H, et al.
    3 Biotech, 2018 Feb;8(2):104.
    PMID: 29404232 DOI: 10.1007/s13205-018-1133-2
    A halophilic bacterium, Virgibacillus sp. strain CD6, was isolated from salted fish and its extracellular protease was characterized. Protease production was found to be highest when yeast extract was used as nitrogen source for growth. The protease exhibited stability at wide range of salt concentration (0-12.5%, w/v), temperatures (20-60 °C), and pH (4-10) with maximum activity at 10.0% (w/v) NaCl, 60 °C, pH 7 and 10, indicating its polyextremophilicity. The protease activity was enhanced in the presence of Mg2+, Mn2+, Cd2+, and Al3+ (107-122% relative activity), and with retention of activity > 80% for all of other metal ions examined (K+, Ca2+, Cu2+, Co2+, Ni2+, Zn2+, and Fe3+). Both PMSF and EDTA inhibited protease activity, denoting serine protease and metalloprotease properties, respectively. High stability (> 70%) was demonstrated in the presence of organic solvents and detergent constituents, and the extracellular protease from strain CD6 was also found to be compatible in commercial detergents. Proteinaceous stain removal efficacy revealed that crude protease of strain CD6 could significantly enhance the performance of commercial detergent. The protease from Virgibacillus sp. strain CD6 could serve as a promising alternative for various applications, especially in detergent industry.
    Matched MeSH terms: Magnesium
  2. Dual Functions of a Hybrid Magnetic Magnesium Oxide Nanocomposite as a Fungicide and Plant Growth Promoter in Agriculture Applications
    Wee JL, Chan YS, Law MC
    ACS Appl Bio Mater, 2023 Nov 20;6(11):4972-4987.
    PMID: 37910790 DOI: 10.1021/acsabm.3c00515
    The use of nanometal oxides in nanoagronomy has garnered considerable attention due to their excellent antifungal and plant growth promotion properties. Hybrid nanometal oxides, which combine the strengths of individual nanomaterials, have emerged as a promising class of materials. In this study, nanomagnesium oxide (n-MgO) and hybrid magnetic nanomagnesium oxide (m/n-MgO) were successfully synthesized via the ultrasound-mediated sol-gel method. Characterization results, including TGA, XRD, VSM, and FTIR, confirmed the successful synthesis of m/n-MgO. Both n-MgO and m/n-MgO underwent antifungal assays and plant growth promotion ability studies, benchmarked against the conventional fungicide-copper oxychloride. This study bridges a significant gap by simultaneously reporting the antifungal properties of both n-MgO and m/n-MgO and their impact on plant growth. The disc diffusion assay suggested that the antifungal activity of n-MgO and m/n-MgO against F. oxysporum was inversely related to the particle size. Notably, n-MgO exhibited superior antifungal performance (lower minimum inhibitory concentration (MIC)) and sustained efficacy compared with m/n-MgO, owing to distinct antifungal mechanisms. Nanorod-shaped MgO, with a smaller size (8.24 ± 5.61 nm) and higher aspect ratio, allowed them to penetrate the fungal cell wall and cause intercellular damage. In contrast, cubical m/n-MgO, with a larger size (20.95 ± 9.99 nm) and lower aspect ratio, accumulate on the fungal cell wall surface, disrupting the wall integrity, albeit less effectively against F. oxysporum. Moreover, in plant growth promotion studies, m/n-MgO-treated samples exhibited a 15.7% stronger promotion effect compared to n-MgO at their respective MICs. In addition, both n-MgO and m/n-MgO outperformed copper oxychloride in terms of antifungal and plant growth promoting activities. Thus, m/n-MgO presents a promising alternative to conventional copper-based fungicides, offering dual functionality as a fungicide and plant growth promoter, while the study also delves into the antifungal mechanisms at the intracellular level, enhancing its novelty.
    Matched MeSH terms: Magnesium Oxide/pharmacology
  3. Electrospun PAN/PEG Nanofibrous Membrane Embedded with a MgO/gC3N4 Nanocomposite for Effective Bone Regeneration
    Danagody B, Bose N, Rajappan K, Iqbal A, Ramanujam GM, Anilkumar AK
    ACS Biomater Sci Eng, 2024 Jan 08;10(1):468-481.
    PMID: 38078836 DOI: 10.1021/acsbiomaterials.3c00892
    Developing biomaterial scaffolds using tissue engineering with physical and chemical surface modification processes can improve the bioactivity and biocompatibility of the materials. The appropriate substrate and site for cell attachment are crucial in cell behavior and biological activities. Therefore, the study aims to develop a conventional electrospun nanofibrous biomaterial using reproducible surface topography, which offers beneficial effects on the cell activities of bone cells. The bioactive MgO/gC3N4 was incorporated on PAN/PEG and fabricated into a nanofibrous membrane using electrospinning. The nanocomposite uniformly distributed on the PAN/PEG nanofiber helps to increase the number of induced pores and reduce the hydrophobicity of PAN. The physiochemical characterization of prepared nanoparticles and nanofibers was carried out using FTIR, X-ray diffraction (XRD), thermogravimetry analysis (TGA), X-ray photoelectron spectroscopy (XPS), and water contact angle measurements. SEM and TEM analyses examined the nanofibrous morphology and the structure of MgO/gC3N4. In vitro studies such as on ALP activity demonstrated the membrane's ability to regenerate new bone and healing capacity. Furthermore, alizarin red staining showed the increasing ability of the cell-cell interaction and calcium content for tissue regeneration. The cytotoxicity of the prepared membrane was about 97.09% of live THP-1 cells on the surface of the MgO/gC3N4@PAN/PEG membrane evaluated using MTT dye staining. The soil burial degradation analysis exhibited that the maximum degradation occurs on the 45th day because of microbial activity. In vitro PBS degradation was observed on the 15th day after the bulk hydrolysis mechanism. Hence, on the basis of the study outcomes, we affirm that the MgO/gC3N4@PAN/PEG nanofibrous membrane can act as a potential bone regenerative substrate.
    Matched MeSH terms: Magnesium Oxide/pharmacology
  4. High-yield purification of an organic solvent-tolerant lipase from Pseudomonas sp. strain S5
    Rahman RN, Baharum SN, Basri M, Salleh AB
    Anal Biochem, 2005 Jun 15;341(2):267-74.
    PMID: 15907872
    An organic solvent-tolerant S5 lipase was purified by affinity chromatography and anion exchange chromatography. The molecular mass of the lipase was estimated to be 60 kDa with 387 purification fold. The optimal temperature and pH were 45 degrees C and 9.0, respectively. The purified lipase was stable at 45 degrees C and pH 6-9. It exhibited the highest stability in the presence of various organic solvents such as n-dodecane, 1-pentanol, and toluene. Ca2+ and Mg2+ stimulated lipase activity, whereas EDTA had no effect on its activity. The S5 lipase exhibited the highest activity in the presence of palm oil as a natural oil and triolein as a synthetic triglyceride. It showed random positional specificity on the thin-layer chromatography.
    Matched MeSH terms: Magnesium/chemistry
  5. Cytotoxicity Analysis of Morphologically Different Sol-Gel-Synthesized MgO Nanoparticles and Their In Vitro Insulin Resistance Reversal Ability in Adipose cells
    Jeevanandam J, Chan YS, Danquah MK, Law MC
    Appl Biochem Biotechnol, 2020 Apr;190(4):1385-1410.
    PMID: 31776944 DOI: 10.1007/s12010-019-03166-z
    Insulin resistance is one of the major factors that leads to type 2 diabetes. Although insulin therapies have been shown to overcome insulin resistance, overweight and hypoglycemia are still observed in most cases. The disadvantages of insulin therapies have driven the interest in developing novel curative agents with enhanced insulin resistance reversibility. Magnesium deficiency has also been recognized as a common problem which leads to insulin resistance in both type 1 and 2 diabetes. Oxide nanoparticles demonstrate highly tunable physicochemical properties that can be exploited by engineers to develop unique oxide nanoparticles for tailored applications. Magnesium supplements for diabetic cells have been reported to increase the insulin resistance reversibility. Hence, it is hypothesized that magnesium oxide (MgO) nanoparticles could be molecularly engineered to offer enhanced therapeutic efficacy in reversing insulin resistance. In the present work, morphologically different MgO nanoparticles were synthesized and evaluated for biophysical characteristics, biocompatibility, cytotoxicity, and insulin resistance reversibility. MTT assay revealed that hexagonally shaped MgO nanoparticles are less toxic to 3T3-L1 adipose cells (diabetic) compared with spherically and rod-shaped MgO nanoparticles. MTT assays using VERO cells (normal, non-diabetic) showed that 400 μg/ml of hexagonal MgO nanoparticles were less toxic to both diabetic and non-diabetic cells. DNS glucose assay and western blot showed that hexagonally shaped MgO nanoparticles had reversed 29.5% of insulin resistance whilst fluorescence microscopy studies indicated that the insulin resistance reversal is due to the activation of intracellular enzymes. The probable mechanism for MgO nanoparticles to induce cytotoxic effect and insulin resistance reversal is discussed.
    Matched MeSH terms: Magnesium Oxide/chemistry*
  6. Bone tissue engineering potentials of 3D printed magnesium-hydroxyapatite in polylactic acid composite scaffolds
    Anita Lett J, Sagadevan S, Léonard E, Fatimah I, Motalib Hossain MA, Mohammad F, et al.
    Artif Organs, 2021 Dec;45(12):1501-1512.
    PMID: 34309044 DOI: 10.1111/aor.14045
    The primary role of bone tissue engineering is to reconcile the damaged bones and facilitate the speedy recovery of the injured bones. However, some of the investigated metallic implants suffer from stress-shielding, palpability, biocompatibility, etc. Consequently, the biodegradable scaffolds fabricated from polymers have gathered much attention from researchers and thus helped the tissue engineering sector by providing many alternative materials whose functionality is similar to that of natural bones. Herein, we present the fabrication and testing of a novel composite, magnesium (Mg)-doped hydroxyapatite (HAp) glazed onto polylactic acid (PLA) scaffolds where polyvinyl alcohol (PVA) used as a binder. For the composite formation, Creality Ender-3 pro High Precision 3D Printer with Shape tool 3D Technology on an FSD machine operated by Catia design software was employed. The composite has been characterized for the crystallinity (XRD), surface functionality (FTIR), morphology (FESEM), biocompatibility (hemolytic and protein absorption), and mechanical properties (stress-strain and maximum compressive strength). The powder XRD analysis confirmed the semicrystalline nature and intact structure of HAp even after doping with Mg, while FTIR studies for the successful formation of Mg-HAp/PVA@PLA composite. The FESEM provided analysis indicated for the 3D porous architecture and well-defined morphology to efficiently transport the nutrients, and the biocompatibility studies are supporting that the composite for blood compatible with the surface being suitable enough for the protein absorption. Finally, the composite's antibacterial activity (against Staphylococcus aureus and Escherichia coli) and the test of mechanical properties supported for the enhanced inhibition of active growth of microorganisms and maximum compressive strength, respectively. Based on the research outcomes of biocompatibility, antibacterial activity, and mechanical resistance, the fabricated Mg-HAp/PVA@PLA composite suits well as a promising biomaterial platform for orthopedic applications by functioning towards the open reduction internal fixation of bone fractures and internal repairs.
    Matched MeSH terms: Magnesium/chemistry
  7. The nutritional value of indigenous fruits and vegetables in Sarawak
    Hoe VB, Siong KH
    Asia Pac J Clin Nutr, 1999 Mar;8(1):24-31.
    PMID: 24393732
    The proximate composition including mineral and vitamin contents of 16 fruits and 46 vegetables (leaves, fruits, palm hearts and shoots) of indigenous origin in Sarawak are provided. Fruits like dabai (Canarium odontophyllum), kembayau (Dacryodes rostrata f. cuspidata), durian nyekak (Durio kutejensis) and durian kuning (Durio graveolens) are very nutritious with high values for energy, protein and potassium. Among the vegetables, the protein content of letup (Passiflora foetida), kepayang (Pangium edule) and tubu (Pycnarrhena tumetacta) is high, ranging from 6 to 7%. The range of nutrients among foods of indigenous origin are generally comparable with those of many cultivated species except for vitamin C, which is lower. Teh Kampung (Leucosyke capitellata) leaves are particularly high in magnesium (626 mg/100 g). Some of the indigenous vegetables contain antinutritional factors. Kepayang has very high levels of hydrogen cyanide (1834 µg/g on dry basis) but this poison can be completely evaporated by boiling. Indigenous fruits and vegetables which are pesticide residue free are important food sources for rural populations. Nutritious indigenous fruits and vegetables have the potential to be promoted for wider use, domestication and commercialization.
    Matched MeSH terms: Magnesium
  8. Fulltext The Effect of Intragastric Gavage of High Dose Green Tea Extract on Serum Status of Magnesium, Calcium, and Zinc
    Khaleel AK, Shaari RB, Nawi MAA, Al-Yassiri AMH
    Asian Pac J Cancer Prev, 2022 Sep 01;23(9):3195-3199.
    PMID: 36172684 DOI: 10.31557/APJCP.2022.23.9.3195
    OBJECTIVE: Green tea (GT) contains polyphenolic flavonoids, different minerals like magnesium, calcium, and zinc, vitamins, amino acids, carbohydrates, proteins, and others. It has a different health benefit. The aim of the present study was to investigate the effect of intragastric gavage of a high dose GT extract on serum biochemical analysis of magnesium, calcium, and zincin juvenile Wistar albino rats.

    METHODS: Twelve rats were used in the study and divided in to two equal groups. All the animals in the control group were intragastically gavaged by distilled water and continues for ten days, from day 24 to day 34 of age, while the animals in the study group were intragastically gavaged by GT extract (300mg/kg/day) which continues also for ten days from day 24 to day 34 of age. On day 34 of age, and two hours after the last dose, the rats were anaesthetized and blood collection by cardiac puncture was taken.

    RESULTS: The results showed that the intragastric gavage of a high dose of GT extract caused a non-significant increase in serum magnesium, and calcium levels (p>0.05), but a significant increase in zinc serum level was seen(p< 0.05).

    CONCLUSION: GT can cause a significant increase in zinc serum level, and this may explain the significant role of GT in the response to different oxidative stress. It is recommended to measure the Zn serum level in rats after a period longer than two hrs from the time of the last dose of intragastric gavage of GT extract.

    Matched MeSH terms: Magnesium*
  9. The effect of temperature change on the working and setting time of two luting cements
    Abdullah H, Pearson GJ
    Asian J Aesthet Dent, 1993 Jul;1(2):91-4.
    PMID: 7921802
    The effect of temperature change on the working and setting time of a glass ionomer luting cement and a resin luting cement was measured using the oscillating rheometer. The time taken for each cement to set was calculated from the chart recordings. It was observed that as the temperature increased, the working and setting time of both materials decreased. However, the reduction was much more marked for the dual curing resin cement.
    Matched MeSH terms: Magnesium Oxide/chemistry*
  10. Understanding the performance and mechanism of Mg-containing oxides as support catalysts in the thermal dry reforming of methane
    Khairudin NF, Sukri MFF, Khavarian M, Mohamed AR
    Beilstein J Nanotechnol, 2018;9:1162-1183.
    PMID: 29719767 DOI: 10.3762/bjnano.9.108
    Dry reforming of methane (DRM) is one of the more promising methods for syngas (synthetic gas) production and co-utilization of methane and carbon dioxide, which are the main greenhouse gases. Magnesium is commonly applied in a Ni-based catalyst in DRM to improve catalyst performance and inhibit carbon deposition. The aim of this review is to gain better insight into recent developments on the use of Mg as a support or promoter for DRM catalysts. Its high basicity and high thermal stability make Mg suitable for introduction into the highly endothermic reaction of DRM. The introduction of Mg as a support or promoter for Ni-based catalysts allows for good metal dispersion on the catalyst surface, which consequently facilitates high catalytic activity and low catalyst deactivation. The mechanism of DRM and carbon formation and reduction are reviewed. This work further explores how different constraints, such as the synthesis method, metal loading, pretreatment, and operating conditions, influence the dry reforming reactions and product yields. In this review, different strategies for enhancing catalytic activity and the effect of metal dispersion on Mg-containing oxide catalysts are highlighted.
    Matched MeSH terms: Magnesium
  11. Fulltext Treatment of river water of Sg. Pusu by using magnesium oxide (MGO) coated with chitosan
    Nik Nur Syafika Pahri, Nur Huda Syazwani Jafri, Husna Ahmad Tajuddin, Yusilawati Ahmad Nor
    Biological and Natural Resources Engineering Journal, 2019;2(1):10-25.
    MyJurnal
    Effective treatment of wastewater is crucial in order to achieve a sustainable development. For instance, highly efficient treatment processes with low capital requirements are the major prerequisite for implementation of the advanced wastewater treatment operations. Among various available treatment methods, the application of coagulation-flocculation process by using natural coagulant; chitosan has vast advantages such as low operating cost, environmental friendly and highly effective in the wastewater treatment operations. The application of nanotechnology in numerous treatment techniques are considered as the most significant advances in water and wastewater treatment practices. The utilization of magnesium oxide (MgO) as nano-adsorbent has recently gained attention as a potential treatment method in water remediation particularly for treating effluents with high amount of organic dyes and heavy metals due to its high treatment efficiency, low cost, versatility and environment compatibility. The purpose of this study was to determine the effectiveness of coagulation-flocculation process when using novel coagulant in which MgO coated with chitosan by investigating the percentage removal of several significant parameters which were turbidity, chemical oxygen demand (COD) and suspended solid. The removal efficiencies were determined throughout a series of experiments carried out using a standard jar test procedure in which three different coagulants; chitosan, MgO coated with chitosan and MgO were tested on water samples taken from Sg. Pusu. In addition, a set of experiments was designed using response surface methodology (RSM) in order to optimize adsorption of chitosan into MgO. The experiments were conducted at various concentrations of chitosan (10-30 mg/ml) and selected MgO dosage ranges (10-30 mg). From the obtained results, it was found that chitosan-MgO coagulant has good removal efficiencies of turbidity, chemical oxygen demand (COD) and suspended solids at 92%, 91%, and 98% respectively from the optimization of adsorption of chitosan-MgO. The MgO coated with chitosan is the best coagulant in this study compared to chitosan and MgO alone because of the ability of treating the river water with up to 90 % removal for all the main parameters. The results showed that coagulation-flocculation is effective as a treatment for treating river water.
    Matched MeSH terms: Magnesium; Magnesium Oxide
  12. Fulltext Salinity-induced changes in the morphology and major mineral nutrient composition of purslane (Portulaca oleracea L.) accessions
    Alam MA, Juraimi AS, Rafii MY, Hamid AA, Aslani F, Hakim MA
    Biol Res, 2016 Apr 18;49:24.
    PMID: 27090643 DOI: 10.1186/s40659-016-0084-5
    This study was undertaken to determine the effects of varied salinity regimes on the morphological traits (plant height, number of leaves, number of flowers, fresh and dry weight) and major mineral composition of 13 selected purslane accessions. Most of the morphological traits measured were reduced at varied salinity levels (0.0, 8, 16, 24 and 32 dS m(-1)), but plant height was found to increase in Ac1 at 16 dS m(-1) salinity, and Ac13 was the most affected accession. The highest reductions in the number of leaves and number of flowers were recorded in Ac13 at 32 dS m(-1) salinity compared to the control. The highest fresh and dry weight reductions were noted in Ac8 and Ac6, respectively, at 32 dS m(-1) salinity, whereas the highest increase in both fresh and dry weight was recorded in Ac9 at 24 dS m(-1) salinity compared to the control. In contrast, at lower salinity levels, all of the measured mineral levels were found to increase and later decrease with increasing salinity, but the performance of different accessions was different depending on the salinity level. A dendrogram was also constructed by UPGMA based on the morphological traits and mineral compositions, in which the 13 accessions were grouped into 5 clusters, indicating greater diversity among them. A three-dimensional principal component analysis also confirmed the output of grouping from cluster analysis.
    Matched MeSH terms: Magnesium/analysis
  13. Dietary intake of magnesium may modulate depression
    Yary T, Aazami S, Soleimannejad K
    Biol Trace Elem Res, 2013 Mar;151(3):324-9.
    PMID: 23238611 DOI: 10.1007/s12011-012-9568-5
    Depressive symptoms are frequent in students and may lead to countless problems. Several hypotheses associate magnesium with depression because of the presence of this mineral in several enzymes, hormones, and neurotransmitters, which may play a key role in the pathological pathways of depression. The aim of this study was to assess whether magnesium intake could modulate depressive symptoms. A cross-sectional study was conducted on a convenience sample of 402 Iranian postgraduate students studying in Malaysia to assess the relationship between magnesium intake and depressive symptoms. The mean age of the participants was 32.54 ± 6.22 years. The results of the study demonstrated an inverse relationship between magnesium intake and depressive symptoms, which persisted even after adjustments for sex, age, body mass index, monthly expenses, close friends, living on campus, smoking (current and former), education, physical activity, and marital status.
    Matched MeSH terms: Magnesium/administration & dosage*; Magnesium/pharmacology*; Magnesium/therapeutic use
  14. Impacts of dynamic degradation on the morphological and mechanical characterisation of porous magnesium scaffold
    Md Saad AP, Prakoso AT, Sulong MA, Basri H, Wahjuningrum DA, Syahrom A
    Biomech Model Mechanobiol, 2019 Jun;18(3):797-811.
    PMID: 30607641 DOI: 10.1007/s10237-018-01115-z
    This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg subjected to a dynamic immersion test for its application as a bone scaffold. Porous Mg was immersed in a dynamic immersion test for 24, 48, and 72 h. Twelve specimens were prepared and scanned using micro-CT and then reconstructed into a 3D model for finite element analysis. The structural properties from the numerical simulation were then compared to the experimental values. Correlations between morphological parameters, structural properties, and fracture type were then made. The relative losses were observed to be in agreement with relative mass loss done experimentally. The degradation rates determined using exact (degraded) surface area at particular immersion times were on average 20% higher than the degradation rates obtained using original surface area. The dynamic degradation has significantly impacted the morphological changes of porous Mg in volume fraction, surface area, and trabecular separation, which in turn affects its structural properties and increases the immersion time.
    Matched MeSH terms: Magnesium/chemistry*
  15. Fulltext Oxidative stress cytotoxicity induced by platinum-doped magnesia nanoparticles in cancer cells
    Al-Fahdawi MQ, Al-Doghachi FAJ, Abdullah QK, Hammad RT, Rasedee A, Ibrahim WN, et al.
    Biomed Pharmacother, 2021 Jun;138:111483.
    PMID: 33744756 DOI: 10.1016/j.biopha.2021.111483
    The aim of this study was to prepare, characterize, and determine the in vitro anticancer effects of platinum-doped magnesia (Pt/MgO) nanoparticles. The chemical compositions, functional groups, and size of nanoparticles were determined using X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and scanning electron microscopy. Pt/MgO nanoparticles were cuboid and in the nanosize range of 30-50 nm. The cytotoxicity of Pt/MgO nanoparticles was determined via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on the human lung and colonic cancer cells (A549 and HT29 respectively) and normal human lung and colonic fibroblasts cells (MRC-5 and CCD-18Co repectively). The Pt/MgO nanoparticles were relatively innocuous to normal cells. Pt/MgO nanoparticles downregulated Bcl-2 and upregulated Bax and p53 tumor suppressor proteins in the cancer cells. Pt/MgO nanoparticles also induced production of reactive oxygen species, decreased cellular glutathione level, and increased lipid peroxidation. Thus, the anticancer effects of Pt/MgO nanoparticles were attributed to the induction of oxidative stress and apoptosis. The study showed the potential of Pt/MgO nanoparticles as an anti-cancer compound.
    Matched MeSH terms: Magnesium Oxide/toxicity*
  16. Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor
    Anis S, Zainal ZA
    Bioresour Technol, 2013 Dec;150:328-37.
    PMID: 24185417 DOI: 10.1016/j.biortech.2013.10.010
    This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content.
    Matched MeSH terms: Magnesium/chemistry
  17. Thermocatalytic treatment of biomass tar model compounds via radio frequency
    Anis S, Zainal ZA, Bakar MZ
    Bioresour Technol, 2013 May;136:117-25.
    PMID: 23567671 DOI: 10.1016/j.biortech.2013.02.049
    A new effective RF tar thermocatalytic treatment process with low energy intensive has been proposed to remove tar from biomass gasification. Toluene and naphthalene as biomass tar model compounds were removed via both thermal and catalytic treatment over a wide temperature range from 850 °C to 1200 °C and 450 °C to 900 °C, respectively at residence time of 0-0.7 s. Thermal characteristics of the new technique are also described in this paper. This study clearly clarified that toluene was much easier to be removed than naphthalene. Soot was found as the final product of thermal treatment of the tar model and completely removed during catalytic treatment. Radical reactions generated by RF non-thermal effect improve the tar removal. The study showed that Y-zeolite has better catalytic activity compared to dolomite on toluene and naphthalene removal due to its acidic nature and large surface area, even at lower reaction temperature of about 550 °C.
    Matched MeSH terms: Magnesium/chemistry
  18. Synthesis of fatty acid methyl ester from crude jatropha (Jatropha curcas Linnaeus) oil using aluminium oxide modified Mg-Zn heterogeneous catalyst
    Olutoye MA, Hameed BH
    Bioresour Technol, 2011 Jun;102(11):6392-8.
    PMID: 21486692 DOI: 10.1016/j.biortech.2011.03.039
    The synthesis of fatty acid methyl esters (FAME) as a substitute to petroleum diesel was investigated in this study from crude jatropha oil (CJO), a non-edible, low-cost alternative feedstock, using aluminium modified heterogeneous basic oxide (Mg-Zn) catalyst. The transesterification reaction with methanol to methyl esters yielded 94% in 6h with methanol-oil ratio of 11:1, catalyst loading of 8.68 wt.% at 182°C and the properties of CJO fuel produced were determine and found to be comparable to the standards according to ASTM. In the range of experimental parameters investigated, it showed that the catalyst is selective to production of methyl esters from oil with high free fatty acid (FFA) and water content of 7.23% and 3.28%, respectively in a single stage process. Thus, jatropha oil is a promising feedstock for methyl ester production and large scale cultivation will help to reduce the product cost.
    Matched MeSH terms: Magnesium/chemistry*
  19. Synthesis of fatty acid methyl ester from palm oil (Elaeis guineensis) with Ky(MgCa)2xO3 as heterogeneous catalyst
    Olutoye MA, Lee SC, Hameed BH
    Bioresour Technol, 2011 Dec;102(23):10777-83.
    PMID: 21983406 DOI: 10.1016/j.biortech.2011.09.033
    Fatty acid methyl esters (FAME) were produced from palm oil using eggshell modified with magnesium and potassium nitrates to form a composite, low-cost heterogeneous catalyst for transesterification. The catalyst, prepared by the combination of impregnation/co-precipitation was calcined at 830 °C for 4 h. Transesterification was conducted at a constant temperature of 65 °C in a batch reactor. Design of experiment (DOE) was used to optimize the reaction parameters, and the conditions that gave highest yield of FAME (85.8%) was 5.35 wt.% catalyst loading at 4.5 h with 16:1 methanol/oil molar ratio. The results revealed that eggshell, a solid waste, can be utilized as low-cost catalyst after modification with magnesium and potassium nitrates for biodiesel production.
    Matched MeSH terms: Magnesium Compounds/chemistry
  20. Synthesis of methyl esters from palm (Elaeis guineensis) oil using cobalt doped MgO as solid oxide catalyst
    Rahman NA, Olutoye MA, Hameed BH
    Bioresour Technol, 2011 Oct;102(20):9749-54.
    PMID: 21855332 DOI: 10.1016/j.biortech.2011.07.023
    The potential of Mg(x)Co(2-)(x)O(2) as heterogeneous reusable catalyst in transesterification of palm oil to methyl ester was investigated. The catalyst was prepared via co-precipitation of the metal hydroxides at different Mg-Co ratios. Mg(1.7)Co(0.3)O(2) catalyst was more active than Mg(0.3)Co(1.7)O(2) in the transesterification of palm oil with methanol. The catalysts calcined at temperature 300 °C for 4 h resulted in highly active oxides and the highest transesterification of 90% was achieved at methanol/oil molar ratio of 9:1, catalyst loading of 5.00 wt.%, reaction temperature of 150 °C and reaction time of 2 h. The catalyst could easily be removed from reaction mixture, but showed 50% decrease in activity when reused due to leaching of active sites.
    Matched MeSH terms: Magnesium Oxide/chemistry*
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