There is currently no feasible method of recycling Cd compounds, despite the fact that Cd product... more There is currently no feasible method of recycling Cd compounds, despite the fact that Cd production, consumption, and environmental release have all skyrocketed in recent decades. This raises serious concerns about the potential dangers of Cd compounds to human health. This highlights the pressing need for cadmium pollution cleanup. Biosorption is one of several viable technologies with several advantages, including low operating costs, very efficient detoxification of toxicants at low concentrations, and a low amount of disposal materials. The biosorption of cadmium onto activated carbon from Tridax procumbens is remodeled using nonlinear regression and the optimal mode was determined by a series of error function assessments. The Freundlich model performed best in statistical tests including root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), and corrected Akaike Information Criterion (AICc). This is in contrast to...
Journal of Environmental Microbiology and Toxicology
In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morga... more In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and analyzing the epidemic trend of COVID-19 in the form of total number of death cases of SARS-COV-2 in The United States as of 20th of July 2020. The MMF model was found to be the best model with the highest adjusted R2 value with the lowest RMSE value. The accuracy and bias factors values were close to unity (1.0). The parameters obtained from the MMF model include maximum growth of death rate (log) of 0.048 (95% ci from 0.047 to 0.048), curve constant (d) that affects the inflection point of 2.34 (95% ci from 2.31 to 2.38) and maximal total number of death (ymax) of 151,356 (95% ci from 147,911 to 154,525). The MMF predicted that the total number of death cases for The United States on the coming 20th of August and 20th of September 2020 will be 148,183 (95% ci of 149,199 to 147,173)...
Journal of Environmental Bioremediation and Toxicology, 2020
In most instances, there exists an inaccuracy in interpretation of adsorption/reduction of substa... more In most instances, there exists an inaccuracy in interpretation of adsorption/reduction of substances using linear technique as it can only provide an approximate value of the measured parameter; the specific adsorption rate. This paper provides for the first-time modelling of the effect of nZVI/BC, nZVI and Biochar (BC) on the adsorption/reduction of nitrobenzene as modelled using Pseudo-1st order (PFO), Pseudo-2nd Order (PSO), Elovich and Avrami models. Pseudo-1st Order was the best model for nZVIBCg, whereas Pseudo-2nd Order was the best model for nZVI and BC on Nitrobenzene (NB) removal based on statistical dependencies that were used such as root-mean-squire error (RMSE), bias factor (BF), Akaike information criterion (AICc) and the adjusted coefficient of determination. Justifiably from the results, coupling nZVI and BC together will help in reducing more of NB than when individual compounds are used.
Journal of Environmental Microbiology and Toxicology, 2021
Because of its extensive usage in industrial applications such as leather tanning, metallurgy, el... more Because of its extensive usage in industrial applications such as leather tanning, metallurgy, electroplating, and refractory materials, chromium is one of the most dangerous trace elements introduced into surface and ground waters. The sorption isotherm of chromium sorption onto calcium alginate nanoparticles were analyzed using ten models—Henry, Langmuir, Dubinin-Radushkevich, Freundlich, BET, Toth, Sips, Fritz-Schlunder IV, Baudu and Fritz-Schlunder V, and fitted using non-linear regression. Only the Toth and Fritz-Schlunder V models were unable to fit the data. Statistical analysis based on root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), corrected AICc (Akaike Information Criterion), BIC and HQC showed that the Langmuir model was the best model in terms of overall best criteria. The calculated evidence ratio was 7 with an AICc probability value of 0.87 indicating that the best model was at least 7 times better...
Bioremediation Science and Technology Research, 2021
An example of biosorption is when the sorbent is made from a biodegradable material. Biosorption ... more An example of biosorption is when the sorbent is made from a biodegradable material. Biosorption is now being seen as a simple, cost-effective, and environmentally acceptable alternative to traditional pollution treatment methods. Bioremediation is one of the branches of bioremediation that is used to minimise pollution in the context of incorrect dye waste disposal. The sorption isotherm of Ethyl Violet onto graphene oxide were analyzed using three models—pseudo-1st, pseudo-2nd and Elovich, and fitted using non-linear regression. Statistical analysis based on root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), corrected AICc (Akaike Information Criterion), Bayesian Information Criterion (BIC) and Hannan–Quinn information criterion (HQC) that showed that the pseudo-second-order model was the best which was the same finding from the original published work. The calculated evidence ratio was 11 with an AICc probability ...
Bulletin of Environmental Science and Sustainable Management (e-ISSN 2716-5353), 2020
The novel corona virus (2019-nCoV) infection has spread rapidly to other provinces and neighbouri... more The novel corona virus (2019-nCoV) infection has spread rapidly to other provinces and neighbouring countries since the emergence of the first cases at Wuhan, China. Estimation of the death cases by mathematical modelling can help to determine the potential and severity of the outbreak and to provide critical information on the type and intensity of disease response. In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and analyzing the epidemic trend of COVID-19 in the form of total number of death cases of SARS-CoV-2 in Brazil as of 15th of July 2020. The MMF model was found to be the best model with the highest adjusted R2 value with the lowest RMSE value. The Accuracy and Bias Factors values were close to unity (1.0). The parameters obtained from the MMF model include maximum growth of death rate (log) of 0.03 (95% CI from 0.02 to 0.028...
Bulletin of Environmental Science and Sustainable Management (e-ISSN 2716-5353), 2020
In this paper, we present various growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-... more In this paper, we present various growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and evaluating the COVID-19 epidemic pattern as of 15 July 2020 in the form of the total number of SARS-CoV-2 deaths in Nigeria. The MMF model was found to be the best model having the highest adjusted R2 value and lowest RMSE value. The values for the Accuracy and Bias Factors were near unity (1.0). The parameters derived from the MMF model include maximum growth rate (log) of 0.02 (95% CI from 0.02 to 0.03), curve constant (d) that affects the infection point of 1.61 (95% CI from 1.42 to 1.79) and maximal total number of death cases (Ymax) of 1,717 (95% CI from 1,428 to 2,123). The model estimated that the total number of death cases for Nigeria on the coming 15th of August and 15th of September 2020 were 940 (95% CI of 847 to 1,043) and 1,101 (95% CI of 968 to 1,252), respectively. The p...
Journal of Biochemistry, Microbiology and Biotechnology, 2020
Microbial heavy metals reduction has an important role in the biological system and in environmen... more Microbial heavy metals reduction has an important role in the biological system and in environmental metals recycling to remove its toxic effects in soil and wastewater. A molybdenum-reducing bacterium with the potential to reduce toxic hexavalent molybdenum to colloidal molybdenum blue (Mo-blue) was isolated from agricultural land in Northwest-Nigeria. The Gram’s stain and microscopic examination reveal that the isolate is a Gram-negative, however, phylogenetic analysis of the 16S rRNA identifies the isolate as Pseudomonas sp. Molybdenum reduction in this bacterium is optimally supported by glucose at 1.0% (w/v). The optimum phosphate and molybdate concentrations supporting molybdate reduction were between 3.5 and 7.5 mM for phosphate and 100 mM molybdate. Molybdate reduction is optimum at 37 ᵒC and pH between 6.5 and 7.5. The capacity of this isolate to reduce toxic molybdenum to a less toxic form is novel and makes the bacterium an important instrument for bioremediation of t...
The application of microorganisms in azo dye remediation has gained significant attention, leadin... more The application of microorganisms in azo dye remediation has gained significant attention, leading to various published studies reporting different methods for obtaining the best dye decolouriser. This paper investigates and compares the role of methods and media used in obtaining a bacterial consortium capable of decolourising azo dye as the sole carbon source, which is extremely rare to find. It was demonstrated that a prolonged acclimation under low substrate availability successfully isolated a novel consortium capable of utilising Reactive Red 120 dye as a sole carbon source in aerobic conditions. This consortium, known as JR3, consists of <i>Pseudomonas aeruginosa</i> strain MM01, <i>Enterobacter sp. </i>strain MM05 and <i>Serratia marcescens </i>strain MM06. Decolourised metabolites of consortium JR3 showed an improvement in mung bean's seed germination and shoot and root length.<b> </b>One-factor-at-time optimisation charac...
Molybdenum is an emerging pollutant in Malaysia. It is very toxic to ruminants and ways to remedi... more Molybdenum is an emerging pollutant in Malaysia. It is very toxic to ruminants and ways to remediate soil and waters contaminated with this metal is urgently needed. Coastal areas remediation warranted a seawater-tolerant molybdenum-reducing species. In this study, we report on the first isolation of a seawater-tolerant and novel Mo-reducing bacterium isolated from a costal area. The bacterium reduced soluble molybdenum into the colloidal molybdenum blue. The bacterium is tentatively identified as <i>Kluyvera</i> sp. strain UPM-FR1 based on molecular phylogenetics analysis. The optimized parameters for molybdenum reduction using response surface method (RSM) occurred at 30 <sup>o</sup>C, pH 6.75, sucrose as a carbon source, 30 mM sodium molybdate and 3.95 mM phosphate. before optimization via RSM, molybdenum reduction through OFAT by <i>Kluyvera</i> sp. strain UPM-FR1 showed a maximum absorbance value of 6.704±0.121 (after dilution) at 865 nm or 4...
Sensitive detection of SARS-CoV-2 nucleocapsid protein in urine and saliva samples after an iron nanoparticle magneto-immuno-preconcentration step
The limits of detection (LOD) values for N-protein detection using SANMAP in phosphate buffered s... more The limits of detection (LOD) values for N-protein detection using SANMAP in phosphate buffered saline, urine and saliva were 0.407 ng/mL (95% confidence interval or C.I. from 0.269 to 0.752), 2.316 ng/mL (95% C.I. from 1.686 to 2.976) and 1.867 ng/mL (95% C.I. from 0.655 to 2.878).
Most of the research report on the toxicity of glyphosate using the formulation instead of the pu... more Most of the research report on the toxicity of glyphosate using the formulation instead of the pure or technical grade glyphosate. However, the low solubility and strong soil sorption capacity of the surfactants means that the highly soluble glyphosate would be the major component of soil runoffs from agricultural areas and impacting aquatic organisms especially to fish. In this study, crossbred red tilapia were exposed to different concentrations of technical grade glyphosate herbicide (25 to 150 mg/L) over a period of 49 days under laboratory condition. Changes in growth performance were evaluated through morphometric measurements. The changes in somatic indices of the fish were determined using the hepato-somatic index (HSI) and gonado-somatic index (GSI) of the fish. The results indicate that of the body mass indices, length and weight, the latter is a more sensitive parameter whilst condition factor is not a sensitive parameter. Other parameters tested such as food conversion r...
A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in... more A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in petroleum oily sludge POS by Cajanus cajan (pigeon pea) on soils treated with five different concentrations (1%, 2%, 3%, 4%, and 5% w/w) of the POS. The response of the plant to oily sludge varied significantly from the untreated control and among the various treatments. The growth of C. cajan was slightly (but not significantly) influenced by the oily sludge in soil; growth of C. cajan at relatively lower concentrations of POS (1 to 3%) was greater than in the treatments with relatively higher concentrations POS (4 to 5%). A significant interaction was observed in the relative growth rates (RGRs) of C. cajan, which significantly increased in the treatments with relatively low POS (1 to 3%) and decrease significantly at higher POS concentrations. The heavy metal content of the plant roots as the POS concentrations were increase show that the concentration of all heavy metals in the root...
Most components of petroleum oily sludge (POS) are toxic, mutagenic and cancer-causing. Often bio... more Most components of petroleum oily sludge (POS) are toxic, mutagenic and cancer-causing. Often bioremediation using microorganisms is hindered by the toxicity of POS. Under this circumstance, phytoremediation is the main option as it can overcome the toxicity of POS. Cajanus cajan a legume plant, was evaluated as a phyto-remediating agent for petroleum oily sludge-spiked soil. Culture dependent and independent methods were used to determine the rhizosphere microorganisms’ composition. Degradation rates were estimated gravimetrically. The population of total heterotrophic bacteria (THRB) was significantly higher in the uncontaminated soil compared to the contaminated rhizosphere soil with C. cajan, but the population of hydrocarbon-utilizing bacteria (HUB) was higher in the contaminated rhizosphere soil. The results show that for 1 to 3% oily sludge concentrations, an increase in microbial counts for all treatments from day 0 to 90 d was observed with the contaminated rhizosphere CR s...
A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow i... more A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow is reported. Optimal conditions for molybdenum reduction were pH 6.3 and at 34°C. Glucose was the best electron donor. Another requirement includes a narrow phosphate concentration between 2.5 and 7.5 mM. A time profile of Mo-blue production shows a lag period of approximately 12 hours, a maximum amount of Mo-blue produced at a molybdate concentration of 20 mM, and a peak production at 52 h of incubation. The heavy metals mercury, silver, copper and chromium inhibited reduction by 91.9, 82.7, 45.5 and 17.4%, respectively. A complete decolourisation of the dye Metanil Yellow at 100 and 150 mg/L occurred at day three and day six of incubations, respectively. Higher concentrations show partial degradation, with an approximately 20% decolourisation observed at 400 mg/L. The bacterium is partially identified based on biochemical analysis as Bacillus sp. strain Neni-10. The absorption spectrum of the Mo-blue suggested the compound is a reduced phosphomolybdate. The isolation of this bacterium, which shows heavy metal reduction and dye-decolorising ability, is sought after, particularly for bioremediation.
Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as 'Crown of God', 'Mahkota D... more Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as 'Crown of God', 'Mahkota Dewa', and 'Pau'. It originates from Papua Island, Indonesia and it grows in tropical areas. Empirically, it is potent in treating the hypertensive,diabetic, cancer and diuretic patients. It has a long history of ethnopharmacological usage, and the lack of information about its biological activities led us to investigate the possible biological activities by characterisation of flavonoids and antimicrobial activity of various part of P. macrocarpa against pathogenic bacteria and fungi. The results showed that kaempferol, myricetin, naringin, and rutin were the major flavonoids present in the pericarp while naringin and quercetin were found in the mesocarp and seed. Furthermore, the antibacterial activity of different parts of P. macrocarpa fruit showed a weak ability to moderate antibacterial activity against pathogenic tested bacteria (inhibition range: 0.93-2.17 cm) at concentration of 0.3 mg/disc. The anti fungi activity was only found in seed extract against Aspergillus niger (1.87 cm) at concentration of 0.3 mg/well. From the
Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is genera... more Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosisin vitroandin vivobased on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin.
Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously ... more Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30 mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5 mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition o...
There is currently no feasible method of recycling Cd compounds, despite the fact that Cd product... more There is currently no feasible method of recycling Cd compounds, despite the fact that Cd production, consumption, and environmental release have all skyrocketed in recent decades. This raises serious concerns about the potential dangers of Cd compounds to human health. This highlights the pressing need for cadmium pollution cleanup. Biosorption is one of several viable technologies with several advantages, including low operating costs, very efficient detoxification of toxicants at low concentrations, and a low amount of disposal materials. The biosorption of cadmium onto activated carbon from Tridax procumbens is remodeled using nonlinear regression and the optimal mode was determined by a series of error function assessments. The Freundlich model performed best in statistical tests including root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), and corrected Akaike Information Criterion (AICc). This is in contrast to...
Journal of Environmental Microbiology and Toxicology
In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morga... more In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and analyzing the epidemic trend of COVID-19 in the form of total number of death cases of SARS-COV-2 in The United States as of 20th of July 2020. The MMF model was found to be the best model with the highest adjusted R2 value with the lowest RMSE value. The accuracy and bias factors values were close to unity (1.0). The parameters obtained from the MMF model include maximum growth of death rate (log) of 0.048 (95% ci from 0.047 to 0.048), curve constant (d) that affects the inflection point of 2.34 (95% ci from 2.31 to 2.38) and maximal total number of death (ymax) of 151,356 (95% ci from 147,911 to 154,525). The MMF predicted that the total number of death cases for The United States on the coming 20th of August and 20th of September 2020 will be 148,183 (95% ci of 149,199 to 147,173)...
Journal of Environmental Bioremediation and Toxicology, 2020
In most instances, there exists an inaccuracy in interpretation of adsorption/reduction of substa... more In most instances, there exists an inaccuracy in interpretation of adsorption/reduction of substances using linear technique as it can only provide an approximate value of the measured parameter; the specific adsorption rate. This paper provides for the first-time modelling of the effect of nZVI/BC, nZVI and Biochar (BC) on the adsorption/reduction of nitrobenzene as modelled using Pseudo-1st order (PFO), Pseudo-2nd Order (PSO), Elovich and Avrami models. Pseudo-1st Order was the best model for nZVIBCg, whereas Pseudo-2nd Order was the best model for nZVI and BC on Nitrobenzene (NB) removal based on statistical dependencies that were used such as root-mean-squire error (RMSE), bias factor (BF), Akaike information criterion (AICc) and the adjusted coefficient of determination. Justifiably from the results, coupling nZVI and BC together will help in reducing more of NB than when individual compounds are used.
Journal of Environmental Microbiology and Toxicology, 2021
Because of its extensive usage in industrial applications such as leather tanning, metallurgy, el... more Because of its extensive usage in industrial applications such as leather tanning, metallurgy, electroplating, and refractory materials, chromium is one of the most dangerous trace elements introduced into surface and ground waters. The sorption isotherm of chromium sorption onto calcium alginate nanoparticles were analyzed using ten models—Henry, Langmuir, Dubinin-Radushkevich, Freundlich, BET, Toth, Sips, Fritz-Schlunder IV, Baudu and Fritz-Schlunder V, and fitted using non-linear regression. Only the Toth and Fritz-Schlunder V models were unable to fit the data. Statistical analysis based on root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), corrected AICc (Akaike Information Criterion), BIC and HQC showed that the Langmuir model was the best model in terms of overall best criteria. The calculated evidence ratio was 7 with an AICc probability value of 0.87 indicating that the best model was at least 7 times better...
Bioremediation Science and Technology Research, 2021
An example of biosorption is when the sorbent is made from a biodegradable material. Biosorption ... more An example of biosorption is when the sorbent is made from a biodegradable material. Biosorption is now being seen as a simple, cost-effective, and environmentally acceptable alternative to traditional pollution treatment methods. Bioremediation is one of the branches of bioremediation that is used to minimise pollution in the context of incorrect dye waste disposal. The sorption isotherm of Ethyl Violet onto graphene oxide were analyzed using three models—pseudo-1st, pseudo-2nd and Elovich, and fitted using non-linear regression. Statistical analysis based on root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF), corrected AICc (Akaike Information Criterion), Bayesian Information Criterion (BIC) and Hannan–Quinn information criterion (HQC) that showed that the pseudo-second-order model was the best which was the same finding from the original published work. The calculated evidence ratio was 11 with an AICc probability ...
Bulletin of Environmental Science and Sustainable Management (e-ISSN 2716-5353), 2020
The novel corona virus (2019-nCoV) infection has spread rapidly to other provinces and neighbouri... more The novel corona virus (2019-nCoV) infection has spread rapidly to other provinces and neighbouring countries since the emergence of the first cases at Wuhan, China. Estimation of the death cases by mathematical modelling can help to determine the potential and severity of the outbreak and to provide critical information on the type and intensity of disease response. In this paper, we present different growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and analyzing the epidemic trend of COVID-19 in the form of total number of death cases of SARS-CoV-2 in Brazil as of 15th of July 2020. The MMF model was found to be the best model with the highest adjusted R2 value with the lowest RMSE value. The Accuracy and Bias Factors values were close to unity (1.0). The parameters obtained from the MMF model include maximum growth of death rate (log) of 0.03 (95% CI from 0.02 to 0.028...
Bulletin of Environmental Science and Sustainable Management (e-ISSN 2716-5353), 2020
In this paper, we present various growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-... more In this paper, we present various growth models such as Von Bertalanffy, Baranyi-Roberts, Morgan-Mercer-Flodin (MMF), modified Richards, modified Gompertz, modified Logistics and Huang in fitting and evaluating the COVID-19 epidemic pattern as of 15 July 2020 in the form of the total number of SARS-CoV-2 deaths in Nigeria. The MMF model was found to be the best model having the highest adjusted R2 value and lowest RMSE value. The values for the Accuracy and Bias Factors were near unity (1.0). The parameters derived from the MMF model include maximum growth rate (log) of 0.02 (95% CI from 0.02 to 0.03), curve constant (d) that affects the infection point of 1.61 (95% CI from 1.42 to 1.79) and maximal total number of death cases (Ymax) of 1,717 (95% CI from 1,428 to 2,123). The model estimated that the total number of death cases for Nigeria on the coming 15th of August and 15th of September 2020 were 940 (95% CI of 847 to 1,043) and 1,101 (95% CI of 968 to 1,252), respectively. The p...
Journal of Biochemistry, Microbiology and Biotechnology, 2020
Microbial heavy metals reduction has an important role in the biological system and in environmen... more Microbial heavy metals reduction has an important role in the biological system and in environmental metals recycling to remove its toxic effects in soil and wastewater. A molybdenum-reducing bacterium with the potential to reduce toxic hexavalent molybdenum to colloidal molybdenum blue (Mo-blue) was isolated from agricultural land in Northwest-Nigeria. The Gram’s stain and microscopic examination reveal that the isolate is a Gram-negative, however, phylogenetic analysis of the 16S rRNA identifies the isolate as Pseudomonas sp. Molybdenum reduction in this bacterium is optimally supported by glucose at 1.0% (w/v). The optimum phosphate and molybdate concentrations supporting molybdate reduction were between 3.5 and 7.5 mM for phosphate and 100 mM molybdate. Molybdate reduction is optimum at 37 ᵒC and pH between 6.5 and 7.5. The capacity of this isolate to reduce toxic molybdenum to a less toxic form is novel and makes the bacterium an important instrument for bioremediation of t...
The application of microorganisms in azo dye remediation has gained significant attention, leadin... more The application of microorganisms in azo dye remediation has gained significant attention, leading to various published studies reporting different methods for obtaining the best dye decolouriser. This paper investigates and compares the role of methods and media used in obtaining a bacterial consortium capable of decolourising azo dye as the sole carbon source, which is extremely rare to find. It was demonstrated that a prolonged acclimation under low substrate availability successfully isolated a novel consortium capable of utilising Reactive Red 120 dye as a sole carbon source in aerobic conditions. This consortium, known as JR3, consists of <i>Pseudomonas aeruginosa</i> strain MM01, <i>Enterobacter sp. </i>strain MM05 and <i>Serratia marcescens </i>strain MM06. Decolourised metabolites of consortium JR3 showed an improvement in mung bean's seed germination and shoot and root length.<b> </b>One-factor-at-time optimisation charac...
Molybdenum is an emerging pollutant in Malaysia. It is very toxic to ruminants and ways to remedi... more Molybdenum is an emerging pollutant in Malaysia. It is very toxic to ruminants and ways to remediate soil and waters contaminated with this metal is urgently needed. Coastal areas remediation warranted a seawater-tolerant molybdenum-reducing species. In this study, we report on the first isolation of a seawater-tolerant and novel Mo-reducing bacterium isolated from a costal area. The bacterium reduced soluble molybdenum into the colloidal molybdenum blue. The bacterium is tentatively identified as <i>Kluyvera</i> sp. strain UPM-FR1 based on molecular phylogenetics analysis. The optimized parameters for molybdenum reduction using response surface method (RSM) occurred at 30 <sup>o</sup>C, pH 6.75, sucrose as a carbon source, 30 mM sodium molybdate and 3.95 mM phosphate. before optimization via RSM, molybdenum reduction through OFAT by <i>Kluyvera</i> sp. strain UPM-FR1 showed a maximum absorbance value of 6.704±0.121 (after dilution) at 865 nm or 4...
Sensitive detection of SARS-CoV-2 nucleocapsid protein in urine and saliva samples after an iron nanoparticle magneto-immuno-preconcentration step
The limits of detection (LOD) values for N-protein detection using SANMAP in phosphate buffered s... more The limits of detection (LOD) values for N-protein detection using SANMAP in phosphate buffered saline, urine and saliva were 0.407 ng/mL (95% confidence interval or C.I. from 0.269 to 0.752), 2.316 ng/mL (95% C.I. from 1.686 to 2.976) and 1.867 ng/mL (95% C.I. from 0.655 to 2.878).
Most of the research report on the toxicity of glyphosate using the formulation instead of the pu... more Most of the research report on the toxicity of glyphosate using the formulation instead of the pure or technical grade glyphosate. However, the low solubility and strong soil sorption capacity of the surfactants means that the highly soluble glyphosate would be the major component of soil runoffs from agricultural areas and impacting aquatic organisms especially to fish. In this study, crossbred red tilapia were exposed to different concentrations of technical grade glyphosate herbicide (25 to 150 mg/L) over a period of 49 days under laboratory condition. Changes in growth performance were evaluated through morphometric measurements. The changes in somatic indices of the fish were determined using the hepato-somatic index (HSI) and gonado-somatic index (GSI) of the fish. The results indicate that of the body mass indices, length and weight, the latter is a more sensitive parameter whilst condition factor is not a sensitive parameter. Other parameters tested such as food conversion r...
A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in... more A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in petroleum oily sludge POS by Cajanus cajan (pigeon pea) on soils treated with five different concentrations (1%, 2%, 3%, 4%, and 5% w/w) of the POS. The response of the plant to oily sludge varied significantly from the untreated control and among the various treatments. The growth of C. cajan was slightly (but not significantly) influenced by the oily sludge in soil; growth of C. cajan at relatively lower concentrations of POS (1 to 3%) was greater than in the treatments with relatively higher concentrations POS (4 to 5%). A significant interaction was observed in the relative growth rates (RGRs) of C. cajan, which significantly increased in the treatments with relatively low POS (1 to 3%) and decrease significantly at higher POS concentrations. The heavy metal content of the plant roots as the POS concentrations were increase show that the concentration of all heavy metals in the root...
Most components of petroleum oily sludge (POS) are toxic, mutagenic and cancer-causing. Often bio... more Most components of petroleum oily sludge (POS) are toxic, mutagenic and cancer-causing. Often bioremediation using microorganisms is hindered by the toxicity of POS. Under this circumstance, phytoremediation is the main option as it can overcome the toxicity of POS. Cajanus cajan a legume plant, was evaluated as a phyto-remediating agent for petroleum oily sludge-spiked soil. Culture dependent and independent methods were used to determine the rhizosphere microorganisms’ composition. Degradation rates were estimated gravimetrically. The population of total heterotrophic bacteria (THRB) was significantly higher in the uncontaminated soil compared to the contaminated rhizosphere soil with C. cajan, but the population of hydrocarbon-utilizing bacteria (HUB) was higher in the contaminated rhizosphere soil. The results show that for 1 to 3% oily sludge concentrations, an increase in microbial counts for all treatments from day 0 to 90 d was observed with the contaminated rhizosphere CR s...
A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow i... more A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow is reported. Optimal conditions for molybdenum reduction were pH 6.3 and at 34°C. Glucose was the best electron donor. Another requirement includes a narrow phosphate concentration between 2.5 and 7.5 mM. A time profile of Mo-blue production shows a lag period of approximately 12 hours, a maximum amount of Mo-blue produced at a molybdate concentration of 20 mM, and a peak production at 52 h of incubation. The heavy metals mercury, silver, copper and chromium inhibited reduction by 91.9, 82.7, 45.5 and 17.4%, respectively. A complete decolourisation of the dye Metanil Yellow at 100 and 150 mg/L occurred at day three and day six of incubations, respectively. Higher concentrations show partial degradation, with an approximately 20% decolourisation observed at 400 mg/L. The bacterium is partially identified based on biochemical analysis as Bacillus sp. strain Neni-10. The absorption spectrum of the Mo-blue suggested the compound is a reduced phosphomolybdate. The isolation of this bacterium, which shows heavy metal reduction and dye-decolorising ability, is sought after, particularly for bioremediation.
Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as 'Crown of God', 'Mahkota D... more Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as 'Crown of God', 'Mahkota Dewa', and 'Pau'. It originates from Papua Island, Indonesia and it grows in tropical areas. Empirically, it is potent in treating the hypertensive,diabetic, cancer and diuretic patients. It has a long history of ethnopharmacological usage, and the lack of information about its biological activities led us to investigate the possible biological activities by characterisation of flavonoids and antimicrobial activity of various part of P. macrocarpa against pathogenic bacteria and fungi. The results showed that kaempferol, myricetin, naringin, and rutin were the major flavonoids present in the pericarp while naringin and quercetin were found in the mesocarp and seed. Furthermore, the antibacterial activity of different parts of P. macrocarpa fruit showed a weak ability to moderate antibacterial activity against pathogenic tested bacteria (inhibition range: 0.93-2.17 cm) at concentration of 0.3 mg/disc. The anti fungi activity was only found in seed extract against Aspergillus niger (1.87 cm) at concentration of 0.3 mg/well. From the
Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is genera... more Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosisin vitroandin vivobased on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin.
Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously ... more Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30 mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5 mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition o...
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Papers by Yunus Shukor