136 research outputs found
Isolation and Characterization of a Molybdenum-reducing and Phenolic- and Catechol-degrading Enterobacter SP. Strain Saw-2
Molybdenum is an emerging pollutant worldwide. The objective of this study is to isolate molybdenum-reducing bacterium with the ability to grow on phenolic compounds (phenol and catechol). The screening process was carried out on a microplate. The bacterium reduced molybdenum in the form of sodium molybdate to molybdenum blue (Mo-blue). The bacterium required a narrow pH range for optimal reduction of molybdenum, i.e. between pH 6.3 and 6.8, with temperature between 34 and 37 oC. Molybdate reduction to Mo-blue was best supported by glucose as the carbon source. However, both phenol and catechol could not support molybdate reduction. Other requirements for molybdate reduction included sodium molybdate concentrations between 15 and 30 mM, and phosphate concentration of 5.0 mM. The bacterium exhibited a Mo-blue absorption spectrum with a shoulder at 700 nm and a maximum peak near the infrared region at 865 nm. The Mo-reducing bacterium was partially identified as Enterobacter sp. strain Saw-2. The capability of this bacterium to grow on toxic phenolic compounds and to detoxify molybdenum made it a significant agent for bioremediation
Pembangunan Biopenderia Enzim berasaskan Kolinasterase untuk Mengesan Kehadiran Bahan Cemar Seperti Racun Serangga dan Logam Berat
Bioteknologi merupakan cabang ilmu yang semakin berkembang seiring dengan kemajuan sesebuah negara. Malaysia juga tidak ketinggalan kerana kesedaran dalam bidang ini bakal memberi impak positif sejajar dengan pembangunan kesemua sektor dalam negara seperti pertanian, perikanan, industri pembuatan, makanan, kesihatan dan kelestarian alam sekitar. Oleh itu, pendedahan ilmu bioteknologi wajar diperluaskan daripada setiap peringkat umur bagi menanam minat dan mampu melahirkan ramai pakar dalam bidang ini. Biopenderia merupakan salah satu cabang bioteknologi yang semakin mendapat perhatian oleh kerana penggunaannya yang terbukti berkesan, cepat, murah dan tidak memerlukan kepakaran yang khusus untuk pengendalian. Dalam konteks ini, pengetahuan mengenai bidang bioteknologi melalui pengaplikasian biopenderia mudah disampaikan dan dapat menjana idea, penciptaan dan inovasi yang baharu pada masa akan datang. Ulasan ini membincangkan asas pengetahuan biopenderia menggunakan kolinasterase sebagai contoh yang berfungsi dalam mengesan kehadiran bahan toksik dalam sesuatu medium terutamanya air. Selain itu juga, kaedah pengendalian biopenderia turut dibincangkan secara terperinci berserta perbandingan dengan kaedah konvensional yang berkos tinggi, mengambil masa yang lama untuk penjanaan data dan memerlukan kepakaran teknikal. Kekangan ini menjadikan biopenderia sebagai kaedah alternatif yang terbukti lebih sensitif untuk mengesan kehadiran bahan toksik seperti racun serangga dan logam berat dalam alam sekita
Enzymatic cyanide detoxification by partially purified cyanide dihydratase obtained from Serratia marcescens strain AQ07.
The partially purified enzyme of indigenously isolated Serratia marcescensstrain AQ07 was utilised to develop the best form of cyanide detoxification method that is eco-friendly and cost effective. The present study evaluates the feasibility of the enzyme to degrade high cyanide concentrations and the possible metabolic pathways involved, for which the protein concentration and cyanide detoxification activity were quantified. Bacterial cells grown in cyanide incorporated medium were disrupted by sonication and the resultant cell free extract were tested for metabolic pathway. The cell free extract was precipitated by ammonium sulphate precipitation and partially purified by ion exchange chromatography using DEAE cellulose. The maximum enzyme activity achieved was 2125 µM/min. The partially purified enzyme was found to be able to detoxify 82% of 2 mM KCN in 10 min of incubation and cyanide degradation (or depletion) rate showing a linear increase with increasing enzyme concentration. The effective accruing of ammonia as metabolite illustrated that the detoxification was ensued via the function of cyanide dihydratase. Additional confirmation through SDS-Page showed that the molecular weight of enzyme was assessed to be ~38 kDa, which is tandem with the reported cyanide dihydratases. Hence, the use of enzyme as a substitute to live bacterial cells in detoxification of cyanide illustrates various advantages such as the capacity to withstand and detoxify higher cyanide concentration and total reduction in the total cost of process since nutrient provision is immaterial
Distribution of Selected Heavy Metals Bioaccumulation in Various Parts of Indigenous Rice (Bokilong, Ponsulak and Taragang) in North Borneo
The prospect of three native upland paddy landraces known as Bokilong, Ponsulak and Taragang as heavy metals accumulator for phytoremediation was determined. Bioaccumulation of heavy metals (As, Cd, Cr, Cu, Fe, Pb, and Zn) in various parts of paddy plants collected from Kiulu valley, North Borneo in the natural conditions during the vegetative phase and harvest season were analysed by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). All selected heavy metals were traced in soil samples of all three paddy landraces rhizosphere where the most available heavy metals were Fe followed by Zn. Heavy metals bioavailability in soil seemed to be influenced by the local climate of the cultivation field. Bokilong landrace is an accumulator of As, Cd, Cu, Pb and Zn. Ponsulak paddy can help clean up the soil by phytoextraction of As, Cr, Cu, Fe and Zn. Taragang paddy has a prospect in phytoextraction of Cd and Pb to remediate excess amount of this element in the soil. Different heavy metals concentration trends were accumulated in these three paddy landraces in grain indicated different nutritional values. Heavy metal uptake characteristic differs between upland paddy landraces and there was also environmental influence affecting the mobility rate of these elements in paddy plant depending on the element type and paddy genotype
Enzymatic cyanide detoxification by partially purified cyanide dihydratase obtained from Serratia marcescens strain AQ07.
The partially purified enzyme of indigenously isolated Serratia marcescensstrain AQ07 was utilised to develop the best form of cyanide detoxification method that is eco-friendly and cost effective. The present study evaluates the feasibility of the enzyme to degrade high cyanide concentrations and the possible metabolic pathways involved, for which the protein concentration and cyanide detoxification activity were quantified. Bacterial cells grown in cyanide incorporated medium were disrupted by sonication and the resultant cell free extract were tested for metabolic pathway. The cell free extract was precipitated by ammonium sulphate precipitation and partially purified by ion exchange chromatography using DEAE cellulose. The maximum enzyme activity achieved was 2125 µM/min. The partially purified enzyme was found to be able to detoxify 82% of 2 mM KCN in 10 min of incubation and cyanide degradation (or depletion) rate showing a linear increase with increasing enzyme concentration. The effective accruing of ammonia as metabolite illustrated that the detoxification was ensued via the function of cyanide dihydratase. Additional confirmation through SDS-Page showed that the molecular weight of enzyme was assessed to be ~38 kDa, which is tandem with the reported cyanide dihydratases. Hence, the use of enzyme as a substitute to live bacterial cells in detoxification of cyanide illustrates various advantages such as the capacity to withstand and detoxify higher cyanide concentration and total reduction in the total cost of process since nutrient provision is immaterial
Lignocellulosic Biomass – A Sustainable Feedstock for Acetone-Butanol-Ethanol Fermentation
Biobutanol has been identified as a promising future biofuel. However, generally the extraction and separation of biobutanol from the fermentation mixture is a costly process. Therefore, the idea of using acetone-butanol-ethanol (ABE) mixture directly as biofuel were proposed to eliminate the recovery process. ABE has been identified as a promising future biofuel. The feedstocks play an important role in the feasibility of ABE as a fuel. Lignocellulosic biomass is seen as a promising feedstock for the production of biofuels. Thus, in this review, ABE biofuel is been summarized from three aspects namely (i) selection of feedstocks, (ii) microbial selection and (iii) hydrolysis, fermentation, and purification techniques. Anaerobic fermentation together with commonly employed recovery processes are discussed in the second part of this review. This review concludes with different challenges and future research in ABE fermentation that can pave the way for future commercialization of this promising biofuel
Toxicity effects of fish histopathology on copper accumulation
Copper is a significant trace element necessary for the normal growth and metabolism of living organisms. However, this element may become very dangerous if used beyond its limit, turning into continuous metal compounds with the ability to accumulate in water and cause imbalance to the biological system. Aquaculture activities can also be affected due to the increase in environmental pollution. Copper is observed with the ability to cause some deleterious effects on fish by its toxicity, which can be evaluated from the molecular and structural level of the organism. This is because fish is one of the aquatic organisms that are able to accumulate heavy metals in their tissue. Generally, this accumulation is influenced by several factors namely, metal concentration, time of exposure, ways of metal uptake, environmental condition (water temperature, pH) and intrinsic factors (fish age, size). Different organs of fish show different affinity to copper accumulation. Therefore, this review was conducted with the purpose of investigating the harmful effects of copper on fish as a result of the accumulation of copper in fish organs and the histopathological alteration encountered in fish
Comparision of staining methods for two dimensional electrophoresis gel resolved with Puntius javanicus liver proteome
The aim of this study was to compare the various staining methods based on commassie briliant blue and silver nitrate stain for the two dimensional gel electrophoresis resolved with Puntius javanicus liver proteome. The staining methods were selected base on the previous report about their compatibility with the mass spectrometry analysis. Silver staining method is known as the most sensitive method to visualize the maximum number of protein spots resolved in 2D gel but it is less sensitive(incompatible) toward mass spectrometry detection. Results of this study showed that a modified staining method using colloidal coomassie blue G-250 (CCB) is roughly similarly sensitive but lower protein spot detected compared with silver staining (SS) as indicated at the number of 303±26 and 693±14of protein resolved in both types of stained gels. The conventional methods of staining using commassie brilliant blue G-250 and R-250 only detected less number of protein spots(128±17and 78±11, respectively) compared to modified CCB staining method. As the commasie brilliant blue stain wasis known to be a very sensitive for mass spectrometry detection, the modified method of CCB was selected for further study on Puntius javanicus liver proteome
Oil palm empty fruit bunches as a promising feedstock for bioethanol production in Malaysia
Depletion of the fossil fuels together with an increase in energy demand is considered as a serious threat to the world. Furthermore, fuel versus food dilemma plays an important role in search of sustainable non-edible feedstocks for production of biofuels. Liquid biofuels such as bioethanol can pave way for a cleaner earth together with less dependency on fossil fuels. Empty fruit bunches (EFBs) is one of the potential biomass wastes, which can be utilized as a raw material for bioethanol production. The high availability of EFBs as a biowaste in Malaysia can endorse the concept of waste-to-wealth that had been long dreamed since late 1990, where unwanted wastes are converted into valuable energy. The three important steps in bioethanol production from EFBs, i.e. pretreatment, hydrolysis, and fermentation are discussed in this paper. This review paper highlights some available literature and detailed information regarding the EFBs as a potential feedstock for bioethanol production in Malaysia. An environmental-friendly bioenergy and zero waste can be anticipated in Malaysia which in turn promotes an economically sustainable bioethanol production. This review is vital as it explores the EFBs potential as a promising feedstock for bioethanol which can be implemented for future commercial purpose
Comparision of staining methods for two dimensional electrophoresis gel resolved with Puntius javanicus liver proteome
The aim of this study was to compare the various staining methods based on commassie briliant blue and silver nitrate stain for the two dimensional gel electrophoresis resolved with Puntius javanicus liver proteome. The staining methods were selected base on the previous reportabout their compatiblitywiththe mass spectrometry analysis. Sliver staining methodis known as the most sensitive method to visualize the maximum number of protein spots resolved in 2D gel but it is less sensitive(incompatible) toward mass spectrometry detection. Results of this study showed that a modifiedstaining method using colloidal coomassie blue G-250 (CCB) is roughly similarly sensitive but lower protein spot detected compared with silver staining (SS) as indicated at the number of 303±26 and 693±14of proteinresolved in both types of stained gels. The conventional methods of staining using commassie brilliant blue G-250 and R-250 only detected less number of protein spots(128±17and 78±11, respectively) compared to modified CCB staining method. As the commasie brilliant blue stain is known to be a very sensitive for mass spectrometry detection, the modified method of CCB was selected for further study on Puntius javanicus liver proteome
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