Journal of Environmental Microbiology and Toxicology最新文献_第8页

Estimation of LC50 and its Confidence Interval for the Effect of Nano-Zero Valent Iron on the Freshwater Zooplankton Species Daphnia magna 纳米零价铁对淡水浮游动物大水蚤影响的LC50及其置信区间估算

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-12-31 DOI: 10.54987/jemat.v6i2.440

Izazy Nur Mohd Jaafar, S. Ahmad, N. A. Yasid

{"title":"Estimation of LC50 and its Confidence Interval for the Effect of Nano-Zero Valent Iron on the Freshwater Zooplankton Species Daphnia magna","authors":"Izazy Nur Mohd Jaafar, S. Ahmad, N. A. Yasid","doi":"10.54987/jemat.v6i2.440","DOIUrl":"https://doi.org/10.54987/jemat.v6i2.440","url":null,"abstract":"Determination of lethal concentration (LC50) of toxicants leading to 50% mortality of test samples in a toxicity test is very important and could be achieved by running Probit analysis. The response is binomial (death or no death) and relationship between response and various doses or concentrations is typically sigmoid. The Probit value can either be manually calculated by hand, or automatically calculated by computer software using a higher accuracy estimation method, namely the maximum likelihood principle. When a published toxicity study failed to report the 95% confidence interval values, the results can be recalculated via software. In this study, the LC50 and 95% confidence interval values of the effect of nano-zero valent iron towards the freshwater zooplankton Daphnia magna is recalculated by employing the Probit analysis in the SPSS software. The results of the Probit modelling exercise gave an LC50 value of 0.405 mg/L (95% confidence interval, CI was from 0.047 to 0.953) for Nanofer 25S, 0.706 mg/L (95% CI was from 0.151 to 3.203) for Nanofer STAR, 1.020 mg/L (95% CI was from 0.683 to 1.445) for Fe2+ and 5.834 mg/L (95% CI was from 4.190 to 9.189) for Fe3+. The wide 95% confidence interval curves for Nanofer 25S and Nanofer STAR indicate a large uncertainty meaning more data in the future should be obtained to increase the CI. The sub lethal concentration (SLC), which is one fourth of the LC50 value for Nanofer 25S, Nanofer STAR, Fe2+ and Fe3+ were 0.101, 0.176, 0.255 and 1.458 mg/L, respectively.","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121783368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Mathematical Modelling of the Growth of Caulobacter crescentus on Caffeine 新月状茎杆菌在咖啡因上生长的数学模型

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-12-31 DOI: 10.54987/jemat.v6i2.438

S. Ibrahim, A. Mansur, S. Ahmad

{"title":"Mathematical Modelling of the Growth of Caulobacter crescentus on Caffeine","authors":"S. Ibrahim, A. Mansur, S. Ahmad","doi":"10.54987/jemat.v6i2.438","DOIUrl":"https://doi.org/10.54987/jemat.v6i2.438","url":null,"abstract":"Caffeine is a purine alkaloid naturally found in many species of plant and can be degraded by bacteria. Prolong caffeine consumption is well-known to have serious adverse effects. The used of linearization technique using natural logarithm transformation, though standard, is erroneous and can just give an estimated value for the sole parameter measured; the specific growth rate. In this paper, for the first time we present different kinetics models such as Von Bertalanffy, Baranyi-Roberts, modified Schnute, modified Richards, modified Gompertz, modified Logistics and most recent Huang were used to get values for the above constants or parameters from Caulobacter crescentus bacterium growth on caffeine. Huang 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 Huang parameters such as Ymax (bacterial growth upper asymptote), Î» (lag time), Âµmax (maximum specific bacterial growth rate) and A or Y0 (bacterial growth lower asymptote) were found to be 1.367 (95% confidence interval of 1.322 - 1.412), 2.683 (95% confidence interval of 2.030 - 3.337), 0.322 (95% confidence interval of 0.252 - 0.392) and 0.324 (95% confidence interval of 0.278 - 0.370).","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114646628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Characterisation of an Acrylamide-Degrading Bacterium and Its Degradation Pathway 一种丙烯酰胺降解菌的特性及其降解途径

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-12-31 DOI: 10.54987/jemat.v6i2.441

Aa'ishah Abd Gafar, M. Shukor

{"title":"Characterisation of an Acrylamide-Degrading Bacterium and Its Degradation Pathway","authors":"Aa'ishah Abd Gafar, M. Shukor","doi":"10.54987/jemat.v6i2.441","DOIUrl":"https://doi.org/10.54987/jemat.v6i2.441","url":null,"abstract":"Widespread use of acrylamide by the industry led to the environmental pollution that results from the indiscriminate discharge of acrylamide. The presence of acrylamide in the environment is a major threat due to its neurotoxic, carcinogenic and teratogenic properties. In this work bacterial isolate identified as Burkholderia sp. strain AQ5-13 is capable of degrading acrylamide as both its carbon and nitrogen sources were screen based on the capability of the bacteria to grow on solid basal salt media that contain 500 mg/L acrylamide as sole carbon and nitrogen sources without supplementation of additional carbon or nitrogen sources. Bacteria grow curve study was carried out by measuring the absorbance value at 600 nm. Burkholderia sp. strain AQ5-13 showed a complete life cycle in five days of incubation with no lag phase identified at the earlier growth phase. Optimum conditions for acrylamide degradation was conducted at different initial pH and incubation temperature. Growth optimisation of the bacteria was measured by plate counting in CFU after 48 h of incubation in 250 mL basal salt media that contain 500 mg/L acrylamide. Burkholderia sp. strain AQ5-13 showed optimum growth in acidic media at pH 5.7 (5.57 log 10 CFU/mL) and optimum growth at 30Â°C (6.84 log 10 CFU/mL) compared to other temperature ranges. Quantitative monitoring of acrylamide degradation was performed using HPLC. Burkholderia sp. strain AQ5-13 could degrade 14% of 500 mg/L acrylamide as its carbon and nitrogen sources after 72 h of incubation at 5 min of retention time. The appearance of acrylic acid peak as an intermediate was not detected, possibly because all the acrylic acid produced had been consumed immediately by the bacterium. The result from this study showed that bacteria Burkholderia sp. strain AQ5-13 has a good potential that can be applied in the bioremediation of waste containing acrylamide.","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123838566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Mathematical Modelling of the Growth of Burkholderia sp. on Glyphosate 伯克霍尔德氏菌在草甘膦上生长的数学模型

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-12-31 DOI: 10.54987/jemat.v6i2.439

M. Manogaran, N. A. Yasid, S. Ahmad

{"title":"Mathematical Modelling of the Growth of Burkholderia sp. on Glyphosate","authors":"M. Manogaran, N. A. Yasid, S. Ahmad","doi":"10.54987/jemat.v6i2.439","DOIUrl":"https://doi.org/10.54987/jemat.v6i2.439","url":null,"abstract":"Glyphosate is an agricultural herbicide with usage in the amounts of thousands of tonnes per year in Malaysia. In certain soils, glyphosate can persist for months and its removal through bioremediation is the most economical and practical. A glyphosate-degrading bacterium has been isolated from contaminated soil. The growth of the bacterium on glyphosate as the sole phosphorous source shows classical sigmoidal profile. Important growth constants can be reliably obtained through nonlinear regression modelling using growth models such as logistic, Gompertz, Richards, Schnute, Baranyi-Roberts, Von Bertalanffy, Buchanan three-phase and the Huang models. The modified Gompertz model was chosen as the best model based on statistical tests such as root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), bias factor (BF), accuracy factor (AF) and corrected AICc (Akaike Information Criterion). Novel constants obtained from the modelling exercise would be useful for further secondary modelling implicating the effect of media conditions and other factors on the growth of this bacterium on glyphosate. The fitted value of maximal growth rate showed a decline when the concentration of glyphosate was increased indicating substrate inhibition. The results from this work can be further used in secondary modelling exercises.","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133361515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Isolation and Characterization of a Molybdenum-reducing Bacillus amyloliquefaciens strain KIK-12 in Soils from Nigeria with the Ability to grow on SDS 尼日利亚土壤中解淀粉芽孢杆菌KIK-12的分离及SDS生长特性研究

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.401

Mohd Zamros Maarof, M. Shukor, O. Mohamad, K. I. Karamba, M. Halmi, M. F. Rahman, H. Yakasai

{"title":"Isolation and Characterization of a Molybdenum-reducing Bacillus amyloliquefaciens strain KIK-12 in Soils from Nigeria with the Ability to grow on SDS","authors":"Mohd Zamros Maarof, M. Shukor, O. Mohamad, K. I. Karamba, M. Halmi, M. F. Rahman, H. Yakasai","doi":"10.54987/jemat.v6i1.401","DOIUrl":"https://doi.org/10.54987/jemat.v6i1.401","url":null,"abstract":"The annual production of chemical toxins and organic pollutants has reached an alarming level. Their eradication from the environment is immensely needed, and bioremediation provides a better alternative for this task. In this study, the ability of molybdenum-reducing bacterium isolated from polluted soil to grow and reduce molybdenum on a variety of hydrocarbons and detergents was investigated. The bacterium was found to reduce molybdate to molybdenum blue at an optimum temperature between 25 and 34 oC, pH between 5.8 and 6.3, molybdate concentration between 30 and 50 mM and phosphate concentration between 5.0 and 7.5 mM. The best electron donor hat support molybdate reduction was glucose, followed by sucrose, fructose, maltose, lactose, l-arabinose, d-mannose, mannitol and cellobiose in decreasing order. The absorption spectrum of the resultant Mo-blue was analogous to that of previous Mo-reducing bacterium and bear resemblance with reduced phosphomolybdate. At 2 ppm mercury (ii), copper (ii) and silver (i) molybdenum reduction was inhibited by 82.4, 61.9 and 47.50%, respectively. Based on the biochemical examination, the bacterium was tentatively identified as Bacillus amyloliquefaciens strain KIK-12. The ability of this bacterium to degrade detergent and detoxify molybdenum makes it a vital tool for bioremediation","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125278383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21

Mathematical Modelling of the Growth of Cajanus cajan in the Presence of Petroleum Oily Sludge Based on the Number of Shoots Produced 石油含油污泥条件下柴豆生长的数学模型——以产芽数为基础

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.398

I. Allamin, S. Ahmad, N. A. Yasid, S. R. Abdullah, M. Halmi, M. Shukor

{"title":"Mathematical Modelling of the Growth of Cajanus cajan in the Presence of Petroleum Oily Sludge Based on the Number of Shoots Produced","authors":"I. Allamin, S. Ahmad, N. A. Yasid, S. R. Abdullah, M. Halmi, M. Shukor","doi":"10.54987/jemat.v6i1.398","DOIUrl":"https://doi.org/10.54987/jemat.v6i1.398","url":null,"abstract":"The use of Cajanus cajan (pigeon pea) or Kacang dhal in the phytoremediation of petroleum sludge in this study is novel. One of the challenges in monitoring the efficiency or inhibition of remediation by this toxic substance is measuring growth indicator. The number of shoots produced under growth on this toxic substance can be used to monitor the efficiency or inhibition and the use of mathematical models in describing the growth curve based on this parameter can give tangible results that can be used in further modelling exercise. In this study we demonstrated on the feasibility of using mathematical models in obtaining growth parameters based on the number of shoots produced under various concentrations of toxicants. The popular modified Gompertz growth model again prove itself as the best models in describing plant growth. The coefficients obtained in this study will be very valuable in secondary modelling exercise. This is the first time that mathematically modelling of the growth rate of C. cajan measured as the increase in number of shoots is carried out to the best of our knowledge.","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115075254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of LC50 and its Confidence Interval for the Effect of Ferrous Sulphate on Catla catla 硫酸亚铁对鲇鱼影响的LC50及其置信区间的估计

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.402

M. Halmi, M. Rahim, A. Othman

引用次数: 6

A Review on Microbial Degradation of 2,4-Dinitrophenol 2,4-二硝基苯酚的微生物降解研究进展

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.404

Sufiah Md. Zin, Syahir Habib, N. A. Yasid, S. Ahmad

引用次数: 3

Modelling the Effect of Heavy Metals on the Growth Rate of Enterobacter sp. Strain Neni-13 on SDS 重金属对肠杆菌ni-13在SDS上生长速率影响的模拟

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.403

M. Shukor, N. Gusmanizar, .. Rusnam

{"title":"Modelling the Effect of Heavy Metals on the Growth Rate of Enterobacter sp. Strain Neni-13 on SDS","authors":"M. Shukor, N. Gusmanizar, .. Rusnam","doi":"10.54987/jemat.v6i1.403","DOIUrl":"https://doi.org/10.54987/jemat.v6i1.403","url":null,"abstract":"The SDS-degrading bacterium Enterobacter sp. strain Neni-13 was strongly inhibited by mercury. Growth of the SDS-degrading bacterium at various concentrations of mercury shows a sigmoidal pattern with lag periods ranging from 7 to 10 h. As the concentration of mercury was increased, the overall growth was inhibited with 1.0 g/L causing an almost cessation of bacterial growth. The growth rates obtained from the modified Gompertz model was then modelled according to the modified Han-Levenspiel, Wang, Liu, modified Andrews and the Amor models. Out of the five models, only Wang, modified Han-Levenspiel and the Liu models were able to fit the curve, whilst the modified Andrews and Amor models were unable to fit the curves. Both the Wang and modified Han-Levenspiel models show acceptable fitting while the Liu model shows poor fitting. Results of the statistical analysis showed that the Wang model was the best model based on the lowest values for RMSE and AICc, highest adjusted correlation coefficient (adR2) and values of AF and BF closest to unity. The parameters obtained from the Wang model, which are Ccrit, ïmax and m which represent critical heavy metal ion concentration (g/l), maximum growth rate (g/l h) and empirical constant values were 0.216 (95%, confidence interval f 0.193 to 0.239), 1.05 (95%, confidence interval of 0.938 to 1.167) and 0.389 (95%, confidence interval of 0.148 to 0.636) respectively.","PeriodicalId":393012,"journal":{"name":"Journal of Environmental Microbiology and Toxicology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125224379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Emulsification Characteristics of Rhamnolipids by Pseudomonas aeruginosa Using Coconut Oil as Carbon Source 以椰子油为碳源的铜绿假单胞菌对鼠李糖脂的乳化特性

Journal of Environmental Microbiology and Toxicology Pub Date : 2018-07-31 DOI: 10.54987/jemat.v6i1.400

Izuani Mohamad Sobri, M. Halim, O. Lai, A. Lajis, M. Yusof, M. Halmi, W. Johari, Helmi Wasoh

引用次数: 8