Metallothioneins (MTs) are cysteine-rich metal-binding proteins that are involved in cell growth regulation, transportation of metal ions and detoxification of heavy metals. A mesocarp-specific metallothionein-like gene (MT3-A) promoter was isolated from the oil palm (Elaeis guineensis Jacq). A vector construct containing the MT3-A promoter fused to the β-glucuronidase (GUS) gene in the pCAMBIA 1304 vector was produced and used in Agrobacterium-mediated transformation of tomato. Histochemical GUS assay of different tissues of transgenic tomato showed that the MT3-A promoter only drove GUS expression in the reproductive tissues and organs, including the anther, fruit and seed coat. Competitive RT-PCR and GUS fluorometric assay showed changes in the level of GUS mRNA and enzyme activity in the transgenic tomato (T(0)). No GUS mRNA was found in roots and leaves of transgenic tomato. In contrast, the leaves of transgenic tomato seedlings (T(1)) produced the highest GUS activity when treated with 150 μM Cu(2+) compared to the control (without Cu(2+)). However, Zn(2+) and Fe(2+) treatments did not show GUS expression in the leaves of the transgenic tomato seedlings. Interestingly, the results showed a breaking-off tissue-specific activity of the oil palm MT3-A promoter in T(1) seedlings of tomato when subjected to Cu(2+) ions.
The aim of this study was to determine the level of exposure to polychlorinated biphenyls (PCBs) and selected heavy metals among fishermen via dietary intake of fish and other seafood from the eastern coast along the Straits of Malacca. This study determined the neurobehavioural performances (based on neurobehavioural core test battery scores) of the fishermen and evaluated the correlations between scores of neurobehavioural core test battery and exposure factors. Ninety fishermen participated in the study. The total fish intakes of the fishermen were measured using a set of food frequency questionnaires. The PCBs contents in the seafood samples ranged between 0.2 and 0.6 pg/g fresh sample. The concentrations of mercury (Hg), arsenic (As), cadmium (Cd), and lead (Pb) in the seafood samples were 1.1-5.4, 0.3-4.4, 0.6-36.1, and 0.02-0.3 μg/g fresh sample, respectively. The PCBs, Hg, As, Cd, and Pb exposures of the fishermen was estimated to be 2.8, 0.02, 4.5, 0.09, and 0.5 pg/kg body weight/day, respectively. PCB and heavy metal exposures through dietary intake of fish and seafood were within the tolerable daily limits. The results of neurobehavioural core test battery revealed that the neurobehavioural performances of the fishermen were not affected due to PCB and heavy metal intoxication. No correlations were found between the exposure and neurobehavioural performance among the fishermen. These data are useful for policy makers to assure the safety and quality of seafood in relation to sea pollution. Although the levels of exposure were low, periodic assessment of the quality of fish and fish products is required due to the polluted seawater.
Formation of carbonate minerals by CO2 sequestration is a potential means to reduce atmospheric CO2 emissions. Vast amount of alkaline and alkali earth metals exist in silicate minerals that may be carbonated. Laboratory experiments carried out to study the dissolution rate in Pahang Sandstone, Malaysia, by CO2 injection at different flow rate in surficial condition. X-ray Powder Diffraction (XRD), Scanning Electron Microscope (SEM) with Energy Dispersive X-ray Spectroscopy (EDX), Atomic Absorption Spectroscopy (AAS) and weight losses measurement were performed to analyze the solid and liquid phase before and after the reaction process. The weight changes and mineral dissolution caused by CO2 injection for two hours CO2 bubbling and one week' aging were 0.28% and 18.74%, respectively. The average variation of concentrations of alkaline earth metals in solution varied from 22.62% for Ca(2+) to 17.42% for Mg(2+), with in between 16.18% observed for the alkali earth metal, potassium. Analysis of variance (ANOVA) test is performed to determine significant differences of the element concentration, including Ca, Mg, and K, before and after the reaction experiment. Such changes show that the deposition of alkali and alkaline earth metals and the dissolution of required elements in sandstone samples are enhanced by CO2 injection.
Ring removal is indicated in a number of clinical circumstances to manage or prevent tourniquet effect of the digit. A ring made from hardened metal may defy commonly known methods of removal. We reported a case of unusual difficulty in removing a ring of hardened metal composition using a dental drill. We believed the unusual circumstances of this case is likely to be repeated in some other clinical practice and this instrument is an appropriate option to consider in such cases.
Pollutants, especially heavy metals like cadmium, Chromium, lead and mercury, play a significant role in causing various water-borne diseases to humans. This study evaluates the sorption properties of bioactive constituents of Moringa oleifera seeds for decontamination of cadmium at laboratory scale. The performance of the bioactive constituent extracted by salt extraction method was enhanced by process optimization with various concentration of bioactive dosages, agitation speed, contact time, pH and heavy metal concentrations. Statistical optimization was carried out for evaluating the polynomial regression model through effect of linear, quadratic and interaction of the factors. The maximum removal of cadmium was 72% by using 0.2 g/l of bioactive dosage.
Nipah virus (NiV) causes fatal respiratory illness and encephalitis in humans and animals. The matrix (M) protein of NiV plays an important role in the viral assembly and budding process. Thus, an access to the NiV M protein is vital to the design of viral antigens as diagnostic reagents. In this study, recombinant DNA technology was successfully adopted in the cloning and expression of NiV M protein. A recombinant expression cassette (baculovirus expression vector) was used to encode an N-terminally His-tagged NiV M protein in insect cells. A time-course study demonstrated that the highest yield of recombinant M protein (400-500 μg) was expressed from 107 infected cells 3 days after infection. A single-step purification method based on metal ion affinity chromatography was established to purify the NiV M protein, which successfully yielded a purity level of 95.67% and a purification factor of 3.39. The Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the purified recombinant M protein (48 kDa) was antigenic and reacted strongly with the serum of a NiV infected pig.
A mannose-binding lectin, termed champedak lectin-M, was isolated from an extract of the crude seeds of champedak (Artocarpus integer). On gel filtration chromatography, the lectin eluted in a single peak at elution volumes corresponding to 64 kDa. SDS-PAGE showed the mannose-binding lectin to be composed of 16.8 kDa polypeptides with some of the polypeptides being disulphide-linked to give dimers. When tested with all isotypes of immunoglobulins, champedak lectin-M demonstrated a selective strong interaction with human IgE and IgM, and a weak interaction with IgA2. The binding interactions of lectin-M were metal ion independent. The lectin was also shown to interact with horseradish peroxidase, ovalbumin, porcine thyroglobulin, human alpha1-acid glycoprotein, transferrin and alpha1-antitrypsin. It demonstrated a binding preference to Man alpha 1-3Man ligands in comparison to Man alpha 1-6Man or Man alpha 1-2Man.
Effect of different storage temperatures on physical and physiological changes of Golden Lily mango was investigated. Zinc oxide (ZnO) nanoparticles edible coating was prepared by sol-gel method and Golden Lily mangoes were dipped in the solution and stored at different (32℃, 27℃ and 5℃) temperatures for 7 days. The mangoes were characterized by Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), Fourier-transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) after 7 days of storage. Both the analysis of FESEM and EDX revealed the highest volume ratio of ZnO nanoparticles with a homogeneous dispersion throughout the mango peel surface is at 5℃. FTIR spectra revealed the absence of Zn–O bonding as metal oxides absorption is expected to be in the region below 700 cm-1. The mangoes stored at 5℃ delayed ripening, slowed down weight loss and found to be firmer than mangoes stored at 32℃ and 27℃.
In the present study, CMSS (carboxymethyl sago starch)-based hydrogel was synthesized by crosslinking with citric acid via esterification and then applied as a metal sorbent to overcome excessive heavy metal pollution. The CMSS/CA (carboxymethyl sago starch/citric acid) hydrogel was characterized by Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The absorption band at 1726 cm-1 was observed in the FT-IR spectrum of CMSS/CA hydrogel and indicated ester bonds formed. Further findings show that the cross-linkages in the CMSS/CA hydrogel increased the thermal stability of CMSS and various sizes of pores were also shown in the SEM micrograph. Conversely, the removal of heavy metals was analyzed using Inductively Coupled Plasma-Optic Emission Spectra (ICP-OES). The effects of the pH of the metal solution, contact time, initial concentration of the metal ions and temperature on the sorption capacity were investigated. Under optimum condition, the sorption capacity of Pb2+, Cu2+, Ni2+ and Zn2+ onto CMSS/CA hydrogel were 64.48, 36.56, 16.21, 18.45 mg/g, respectively. The experiments demonstrated that CMSS/CA hydrogel has high selectivity towards Pb2+ in both non-competitive and competitive conditions. In conclusion, the CMSS/CA hydrogel as a natural based heavy metal sorption material exhibited a promising performance, especially in the sorption of Pb2+ for wastewater treatment.
Heavy metal pollution has become a major concern globally as it contaminates eco-system, water networks and as finely suspended particles in air. In this study, the effects of elevated silver nanoparticle (AgNPs) levels as a model system of heavy metals, in the presence of microalgal crude extracts (MCEs) at different ratios, were evaluated against the non-cancerous Vero cells, and the cancerous MCF-7 and 4T1 cells. The MCEs were developed from water (W) and ethanol (ETH) as green solvents. The AgNPs-MCEs-W at the 4:1 and 5:1 ratios (v/v) after 48 and 72 h treatment, respectively, showed the IC50 values of 83.17-95.49 and 70.79-91.20 μg/ml on Vero cells, 13.18-28.18 and 12.58-25.7 μg/ml on MCF-7; and 16.21-33.88 and 14.79-26.91 μg/ml on 4T1 cells. In comparison, the AgNPs-MCEs-ETH formulation achieved the IC50 values of 56.23-89.12 and 63.09-91.2 μg/ml on Vero cells, 10.47-19.95 and 13.48-26.61 μg/ml on MCF-7; 14.12-50.11 and 15.13-58.88 μg/ml on 4T1 cells, respectively. After 48 and 72 h treatment, the AgNPs-MCE-CHL at the 4:1 and 5:1 ratios exhibited the IC50 of 51.28-75.85 and 48.97-69.18 μg/ml on Vero cells, and higher cytotoxicity at 10.47-16.98 and 6.19-14.45 μg/ml against MCF-7 cells, and 15.84-31.62 and 12.58-24.54 μg/ml on 4T1 cells, respectively. The AgNPs-MCEs-W and ETH resulted in low apoptotic events in the Vero cells after 24 h, but very high early and late apoptotic events in the cancerous cells. The Liquid Chromatography-Mass Spectrometry-Electrospray Ionization (LC-MS-ESI) metabolite profiling of the MCEs exhibited 64 metabolites in negative ion and 56 metabolites in positive ion mode, belonging to different classes. The microalgal metabolites, principally the anti-oxidative components, could have reduced the toxicity of the AgNPs against Vero cells, whilst retaining the cytotoxicity against the cancerous cells.
This paper presents the adsorption capacity of a biosorbent derived from the inner part of durian (Durio zibethinus) rinds, which are a low-cost and abundant agro-waste material. The durian rind sorbent has been successfully utilized to remove lanthanum (La) and yttrium (Y) ions from their binary aqueous solution. The effects of several adsorption parameters including contact time, pH, concentrations of La and Y, and temperature on the removal of La and Y ions were investigated. The adsorption isotherm and kinetics of the metal ions were also evaluated in detail. Both La and Y ions were efficiently adsorbed by the biosorbent with optimum adsorption capacity as high as 71 mg La and 35 mg Y per gram biosorbent, respectively. The simultaneous adsorption of La and Y ions follows Langmuir isotherm model, due to the favorable chelation and strong chemical interactions between the functional groups on the surface of the biosorbent and the metal ions. The addition of oxygen content after adsorption offers an interpretation that the rare-earth metal ions are chelated and incorporated most probably in the form of metal oxides. With such high adsorption capacity of La and Y ions, the durian rind sorbent could potentially be used to treat contaminated wastewater containing La and Y metal ions, as well as for separating and extracting rare-earth metal ions from crude minerals.
Processing of by-product heavy minerals (amang) from tin mining involves potential exposure to external and internal sources of radioactivity. The radioactivity arises through the presence of thorium and uranium series radionuclides in the various minerals. Monazite is the most radioactive mineral, containing 3% to 7% thorium by weight, while ilmenite is generally the least radioactive mineral containing typically less than 0.05% thorium. External exposure occurs when workers are in close proximity to accumulations or stockpiles of the radioactive minerals, whereas internal exposure occurs when workers are involved in dusty processes. This paper summarizes the nature of the amang industry in South East Asia and presents the results of preliminary measurements of external radiation and airborne radioactivity in twelve Malaysian and Thai plants. Although constrained by a paucity of exposure data, it is concluded that radiation doses to some amang plant workers may approach or exceed international standards and that appropriate control measures are required as a matter of priority, Radiation doses may approach or exceed 100 mSv in situations where workers are exposed to excessive levels of ambient dust and no protective measures are used. Observations and recommendations are made relating to monitoring and surveillance, instruction and training, and engineering and administrative protection measures.
Edible bird's nest (EBN) is recognized as a nourishing food among Chinese people. The efficacy of EBN was stated in the records of traditional Chinese medicine and its activities have been reported in many researches. Malaysia is the second largest exporter of EBNs in the world, after Indonesia. For many years, EBN trade to China was not regulated until August 2011, when a safety alert was triggered for the consumption of EBNs. China banned the import of EBNs from Malaysia and Indonesia due to high level of nitrite. Since then, the Malaysia government has formulated Malaysia Standards for swiftlet farming (MS 2273:2012), edible bird's nest processing plant design and management (MS 2333:2010), and edible bird's nest product quality (MS 2334:2011) to enable the industry to meet the specified standards for the export to China. On the other hand, Indonesia's EBN industry formulated a standard operating procedure (SOP) for exportation to China. Both countries can export EBNs to China by complying with the standards and SOPs. EBN contaminants may include but not limited to nitrite, heavy metals, excessive minerals, fungi, bacteria, and mites. The possible source of contaminants may come from the swiftlet farms and the swiftlets or introduced during processing, storage, and transportation of EBNs, or adulterants. Swiftlet house design and management, and EBN processing affect the bird's nest color. Degradation of its optical quality has an impact on the selling price, and color changes are tied together with nitrite level. In this review, the current and future prospects of EBNs in Malaysia and Indonesia in terms of their quality, and the research on the contaminants and their effects on EBN color changes are discussed.
Introduction: In Malaysia, herbal medicines are used for variety of reasons including health promotion and home remedies during pregnancy and postpartum with Manjakani (Quercus infectoria) as one of the most commonly consumed herbs. Herbal medicines consumption had been linked to heavy metals contamination and transfer from mother to infant and may affect infant’s growth and development. This study aims to (i) determine Manjakani consumption among postpartum mothers, (ii) quantify its heavy metals level, namely lead, cadmium, arsenic and chromium, and (iii) determine health risk associated with its consumption. Methods: A cross-sectional study involving 106 postpartum mothers was carried out in Kuala Lumpur. Six samples of Manjakani were sampled and extracted using microwave digester and analysed using Inductively coupled plasma mass spectrometry (ICP-MS). Non-carcinogenic health risks for herbal medicine consumption were calculated using Hazard Quotient (HQ). Results: Manjakani was consumed by 16% of mothers (n=17). Highest level of the metals was shown by chromium with mean concentration of 4210 ± 1910 ug/kg, followed by lead (170.8 ± 193.2), arsenic (39.3 ± 27.1) and cadmium (7.7 ± 0.76). There were no significant non-carcinogenic health risks with lead, arsenic, chromium and cadmium contamination (HQ < 1). Conclusion: Manjakani is consumed by mothers during confinement period. Heavy metals were quantified in Manjakani although no significant association was observed with socio-demographic characteristics and birth outcomes.
Phytoremediation is one of the environmental-friendly and cost-effective systems for the treatment of wastewater, including industrial wastewater such as palm oil mill effluent final discharge (POME FD). However, the effects of the wastewater on the phytoremediator plants, in term of growth performance, lignocellulosic composition, and the presence of nutrients and heavy metals in the plants are not yet well studied. In the present work, we demonstrated that POME FD increased the growth of P. purpureum. The height increment of P. purpureum supplied with POME FD (treatment) was 61.72% as compared to those supplied with rain water (control) which was 14.42%. For lignocellulosic composition, the cellulose percentages were 38.77 ± 0.29% (treatment) and 34.16 ± 1.01% (control), and the difference was significant. These results indicated that POME FD could be a source of plant nutrients, which P. purpureum can absorb for growth. It was also found that the heavy metals (Al, As, Cd, Co, Cr, Ni and Pb) inside the plant were below the standard limit of the World Health Organization (WHO). Since POME FD was shown to have no adverse effects on P. purpureum, further research regarding the potential application of P. purpureum following phytoremediation of POME FD such as biofuel production is warranted to evaluate its potential use to fit into the waste-to-wealth agenda.
The remarkable journey of progression of mankind has created various impacts in the form of polluted environment, amassed heavy metals and depleting resources. This alarming situation demands sustainable energy resources and approaches to deal with these environmental hazards and power deficit. Pyrolysis and co-pyrolysis address both energy and environmental issues caused by civilization and industrialization. The processes use hazardous waste materials including waste tires, plastic and medical waste, and biomass waste such as livestock waste and agricultural waste as feedstock to produce gas, char and pyrolysis oil for energy production. Usage of hazardous materials as pyrolysis and co-pyrolysis feedstock reduces disposal of harmful substances into environment, reducing occurrence of soil and water pollution, and substituting the non-renewable feedstock, fossil fuels. As compared to combustion, pyrolysis and co-pyrolysis have less emission of air pollutants and act as alternative options to landfill disposal and incineration for hazardous materials and biomass waste. Hence, stabilizing heavy metals and solving the energy and waste management problems. This review discusses the pyrolysis and co-pyrolysis of biomass and harmful wastes to strive towards circular economy and eco-friendly, cleaner energy with minimum waste disposal, reducing negative impact on the planet and creating future possibilities.
Macrobrachium rosenbergii nodavirus (MrNV) is the causative agent of white tail disease (WTD) which seriously impedes the production of the giant freshwater prawn and has a major economic impact. MrNV contains two segmented RNA molecules, which encode the RNA dependent RNA polymerase (RdRp) and the capsid protein (MrNV-CP) containing 371 amino acid residues. MrNV-CP comprises of the Shell (S) and the Protruding (P) domains, ranging from amino acid residues 1-252 and 253-371, respectively. The P-domain assembles into dimeric protruding spikes, and it is believed to be involved in host cell attachment and internalization. In this study, the recombinant P-domain of MrNV-CP was successfully cloned and expressed in Escherichia coli, purified with an immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC) up to ~90% purity. Characterization of the purified recombinant P-domain with SEC revealed that it formed dimers, and dynamic light scattering (DLS) analysis demonstrated that the hydrodynamic diameter of the dimers was ~6 nm. Circular dichroism (CD) analysis showed that the P-domain contained 67.9% of beta-sheets, but without alpha-helical structures. This is in good agreement with the cryo-electron microscopic analysis of MrNV which demonstrated that the P-domain contains only beta-stranded structures. Our findings of this study provide essential information for the production of the P-domain of MrNV-CP that will aid future studies particularly studies that will shed light on anti-viral drug discovery and provide an understanding of virus-host interactions and the viral pathogenicity.
Bacterial isolates from 30 farmed bullfrogs (Lithobates catesbeianus) weighing 500-600 g at Johore, Malaysia with external clinical signs of ulcer, red leg and torticollis were tested for their antibiograms and heavy metal tolerance patterns. A total of 17 bacterial species with 77 strains were successfully isolated and assigned to 21 antibiotics and 4 types of heavy metal (Hg(2+), Cr(6+), Cd(2+), Cu(2+)). Results revealed that bacteria were resistant against lincomycin (92%), oleandomycin (72.7%) and furazolidone (71.4%) while being susceptible to chloramphenicol and florfenicol at 97.4%. The multiple antibiotic resistance (MAR) index for C. freundii, E. coli and M. morganii was high with the value up to 0.71. Bacterial strains were found to exhibit 100 % resistance to chromium and mercury. High correlation of resistance against both antibiotics and heavy metals was found (71.4 to 100%) between bullfrog bacteria isolates, except bacteria that were resistant to kanamycin showed only 25% resistance against Cu(2+). Based on the results in this study, bacterial pathogens of bullfrog culture in Johore, Malaysia, were highly resistant to both antibiotics and heavy metals.
Introduction: Consumption of Chinese Herbal Medicine (CHMs) have escalated globally. They are preferred treat- ment for minor diseases or disorders. In Malaysia, CHMs are common home remedies during pregnancy and postpar- tum. Angelica sinensis (Danggui) is a staple CHMs during postpartum for purpose of nourishing blood and resolving stasis. Concerns are raised over possible heavy metals toxicity. Objective: This study aims to (i) determine Danggui consumption among postpartum mothers, (ii) quantify its heavy metals level, namely Lead (Pb), Cadmium (Cd), Ar- senic (As) and Chromium (Cr) and (iii) determine health risks of Danggui consumption among mothers. Methods: A cross-sectional study involving 112 postpartum mothers was carried out in Kuala Lumpur. Danggui samples were collected from nine districts in Kuala Lumpur (Segambut, Seputeh, Cheras, Kepong, Bandar Tun Razak, Titiwangsa, Setiawangsa, Batu and Lembah Pantai). Heavy metals were extracted using microwave digester and analysed using Inductively coupled plasma mass spectrometry (ICPMS). Hazard Quotient (HQ) was used to determine non-carcino- genic health risks for herbal medicine consumption. Results: Danggui was consumed by 19.6% of mothers (n=22). Among them, incidence of jaundice was 63.6% and need for phototherapy was 40.9%. Heavy metals contamina- tions were found in the decreasing order of Cr > As > Pb > Cd with median (interquartile) of 3996.3 (2805.6) μg/ kg, 128.3 (56.7), 98.6 (99.1) and 37.0 (35.0) respectively. No non-carcinogenic health risks were found for all four metals. Conclusion: Alarming concentrations of heavy metals were quantified in Danggui warranting for further in- vestigation to safeguard health of postpartum mothers.