scholarly journals Growth Optimization of Glyphosate-based Herbicides Utilizing Bacteria isolated from Lotic Water of Ogini Stream, Nigeria

2021 ◽  
Vol 2 (6) ◽  
pp. 1-5
Author(s):  
R. E. Aso ◽  
C. Hammuel ◽  
M. Daji ◽  
J. Briska

Glyphosate-based herbicides are often used for the control of weeds grown on agricultural fields or farms. Different health problems have been reported to be associated with the use of glyphosate-based herbicides mainly due to their toxicity level. Thus, finding glyphosate utilizing microorganisms to remediate the glyphosate-based herbicides in the environment is crucial. The culture conditions for maximum utilization of glyphosate by bacterial isolates, Stenotrophomonas maltophilia, Bacillus cereus and Enterobacter aerogenes previously isolated from Ugini stream close to corn fields treated with glyphosate-based herbicide at Ofagbe, Delta State, Nigeria were optimized using mineral salt medium containing glyphosate as carbon source. The varied culture parameters assessed were temperature (30, 37 and 40 oC), pH (5, 6, 7, 8 and 9), initial glyphosate concentration (1, 3, 5, 7 and 9 g/L) and incubation time (2-14 days). Optical density (OD) at 560 nm of the culture was used to estimate cell growth or cell load of the glyphosate utilizing bacteria strains at every 2 days for 14 days. The following optimal conditions were determined: initial pH 9.0, incubation temperature 30 °C, initial concentration of glyphosate (1g/L) and incubation time of 12 days. Of the isolates on the medium containing the herbicide as sole carbon and energy source, Bacillus cereus showed the highest growth level (OD average, 0.127, pH average, 6.26. This was followed by Stenotrophomonas maltophilia (OD average = 0.114, pH average = 6.44) and Enterobacter aerogenes (OD average = 0.100, pH average, 6.56). At the increased of glyphosate in the medium there was decreased in growth of the bacteria. Bacillus cereus, Stenotrophomonas maltophilia and Enterobacter aerogenes indicated a high capacity to be able to degrade glyphosate. It is therefore concluded that the bacteria employed in this research can be recommended for bioremediation of environments contaminated with this chemical and further research should conducted to ascertain the catabolic genes present in these individual glyphosate degrading bacteria.

2010 ◽  
Vol 178 ◽  
pp. 59-64
Author(s):  
Xing Hua Zhao ◽  
Xin He ◽  
Jian Hua Wang

Eight swainsonine (SW)-degrading bacteria were isolated from the soil where locoweed was buried for 6 months and one of the strains (YLZZ-2) was selected for further study. Based on morphology, physiologic tests, 16S rDNA sequence, and phylogenetic characteristics, the strain showed the greatest similarity to members of the order Stenotrophomonap and the closest to members of the Stenotrophomonas maltophilia group. The ability of the strain to degrade SW, as sole carbon source, was investigated under different culture conditions. The preferential temperature and initial pH value for the strain were 25~35 °C and 6.0~9.0, respectively. The optimal temperature for the strain was 30 °C and the optimal pH value was 7.0. There was positive correlation between degradation rate and inoculation amount. The growth of stain YLZZ-2 and degradation rate were fast, and YLZZ-2 could completely degradate 400 mg/L swainsoine within 24 h. There was a linear relationship between the growth of stain YLZZ-2 and degradation of swainsonine. These results highlight the potential of this bacterium to be used in detoxifying of SW in livestock consuming locoweed.


Author(s):  
Xuanjiang Yang ◽  
Panpan Guo ◽  
Miao Li ◽  
Hualong Li ◽  
Zelin Hu ◽  
...  

(1) Objective: The objective of this study was to screen amoxicillin (AMX)-degrading bacterial strains in pig manure and optimize the fermentation conditions for these strains to achieve high fermentation rate, which can provide an effective way for the practical application of bacterial strains as antibiotic-degrading bacterial in treating livestock waste for antibiotic residues. (2) Methods: Antibiotic susceptibility tests and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) were employed to screen AMX-degrading bacterial strains in pig manure. The culture conditions were optimized for AMX-degrading bacterial strains using Plackeet–Burman design (PBD), the steepest ascent design, and the response surface methods, coupled with the Box–Behnken design (BBD). The effects of culture time, temperature, rotator (mixing) speed, inoculum level, and initial pH value on the growth of AMX-degrading strains were investigated. Experimental data obtained from BBD were utilized to generate a second-order polynomial regression model for evaluating the effects of the tested variables on the optical density at 600 nm (OD600) of culture solutions as the growth indicator for the screened AMX-degrading strains. (3) Results: The initial pH, culture time, and the inoculum level had significant effects on the OD600 value (growth) of the screened AMX-degrading strains. The initial pH value was found to be the most critical factor influencing the growth of bacteria. The optimized culture condition for the bacterial growth determined by the response surface methodology was: the initial pH of 6.9, culture time of 52 h, and inoculum level of 2%. The average OD value of 12 different fermentation conditions in the initial fermentation tests in this study was 1.72 and the optimization resulted in an OD value of 3.00. The verification experiment resulted in an OD value of 2.94, which confirmed the adequacy of the optimization model for the determining the optimal culture condition. (4) Conclusions: The growth of the screened strain of AMX-degrading bacteria could be optimized by changing the fermentation conditions. The optimization could be achieved by using the Box–Behnken response surface method and Plackett–Burman experimental design.


2017 ◽  
Vol 4 (10) ◽  
pp. 171012 ◽  
Author(s):  
Miao Ye ◽  
Linghong Sun ◽  
Ru Yang ◽  
Zaigui Wang ◽  
KeZong Qi

The proper culture conditions for producing cellulase of Bacillus amyloliquefaciens S1, isolated from the cecum of goose was optimized by single-factor experiment combined with orthogonal test. The properties of the cellulase were investigated by DNS method. The appropriate doses of B. amyloliquefaciens S1 were obtained by adding them to goose feed. It indicated that the suitable culture conditions of producing cellulase were the culture temperature of 37°C, the initial pH of 7.0, the incubation time of 72 h and the loaded liquid volume of 75 ml per 250 ml. The effects of each factor on producing cellulase by B. amyloliquefaciens S1 were as follows: initial pH > incubation time = culture temperature > loaded liquid volume. The optimum reaction temperature and pH were 50°C and 7.0, respectively. This enzyme is a kind of neutral cellulase that possesses resistance to heat and acidity. It showed high activity to absorbent cotton, soya bean meal and filter paper. By adding different doses of B. amyloliquefaciens S1 to the goose feed, it was found that the egg production, average egg weight, fertilization rate and the hatching rate were promoted both in experiment 1 (1.5 g kg −1 ) and experiment 2 (3 g kg −1 ). Also the difference of egg production, fertilization rate and hatching rate between experiment 1 and control group was obvious ( p  < 0.05), and the average egg weight was significantly increased in experiment 2 ( p  < 0.05).


2019 ◽  
Vol 12 (8) ◽  
pp. 1352-1357 ◽  
Author(s):  
Harnentis Harnentis ◽  
Nurmiati Nurmiati ◽  
Yetti Marlida ◽  
Frederick Adzitey ◽  
Nurul Huda

Aim: This study aimed at optimizing γ-aminobutyric acid (GABA) production using lactic acid bacteria (LAB) of an Indonesian indigenous fermented buffalo milk (dadih) origin. This study utilized LAB previously cultured from dadih that has the ability to produce GABA. Materials and Methods: The study started with the identification of selected LAB by 16S rRNA, followed by optimization of GABA production by culture conditions using different initial pH, temperature, glutamate concentration, incubation time, carbon, and nitrogen sources. 16S rRNA polymerase chain reaction and analysis by phylogenetic were used to identify Lactobacillus plantarum (coded as N5) responsible for the production of GABA. Results: GABA production by high-performance liquid chromatography was highest at pH of 5.5, temperature of 36°C, glutamate concentration of 500 mM, and incubation time of 84 h. Peptone and glucose served as the nitrogen and carbon sources, respectively, whereas GABA was produced at optimum fermentation condition of 211.169 mM. Conclusion: Production of GABA by L. plantarum N5 was influenced by initial pH of 5.5, glutamic acid concentration, nitrogen source, glucose as carbon source, and incubation temperature and time. Keywords: fermented buffalo milk, Indonesian indigenous product, lactic acid bacteria, γ-aminobutyric acid.


2011 ◽  
Vol 230-232 ◽  
pp. 1119-1122 ◽  
Author(s):  
Yan Li Mao ◽  
Chang Xun Tian ◽  
Ji Wei Zhu ◽  
Tai Zhi Zhang ◽  
Lv Bao Tong

The optimal conditions of production of biopolymer by the culture of Bacillus cereus B-11 were examined, using molasses wastewater to replace glucose as carbon source and energy source in the culture medium. Results showed that the COD concentration in molasses wastewater favorable for the production of the biopolymer was 5000 mg•L-1, and inoculum size of 5%(v/v), 28◦C, initial pH 7.0 and shaking speed of 150 r•min-1, under the optimal culture conditions, the highest flocculating activity achieved for Kaolin suspension was 98.5% and 3.55 g biopolymer /L broth was obtained. The biopolymer was effective in flocculating some soluble reactive dyes in aqueous solution, reactive Light-Yellow K-4G and reactive Turquoise Blue KN-G with a decolorization efficiency of 97.5 and 94.7%, respectively,using 25 mL of the flocculant in 500 mL of 100 mg•L-1 dye solution.


2019 ◽  
pp. 441-449
Author(s):  
Merike Merimaa ◽  
Eeva Heinaru ◽  
Merit Lehiste ◽  
Signe Viggor ◽  
Ain Heinaru

Successful bioaugmentation requires that bacterial strains introduced into the polluted area must be able to adapt to new environmental conditions and retain high enough catabolic activity. The strains should degrade pollutant present at high concentrations, while having high affinity for the pollutants for their thorough degradation. The transfer of genetic information from introduced donor strain to indigenous bacterial population increases the biodegradation potential. As laboratory-selected strains can be poor survivors and lose catabolic activity in mixed microbial ecosystems, the indigenous biodegradative strains isolated from the river water continuously polluted with phenolic compounds of oil shale leachate may serve as inoculants for bioaugmentation. We have shown that the native phenol- and p-cresol-degrading community could be grouped according to the presence of catabolic genes involved in catabolism of aromatic compounds. The selected representative strains of different catabolic types of degradation of phenol and p-cresol were identified as Pseudomonas mendocina (strain PCl) and P. jluorescens (strains PC! 8, PC24). Catabolic potential of these strains was studied on the basis of phenol hydroxylase, p-cresol methylhydroxylase and catechol 2,3-dioxygenase genes. The occurrence and conjugation of plasmid DNA were revealed in these strains. The ability of the selected strains to degrade several phenolic compounds in natural phenolic wastewater in which the compounds were present in multicomponent mixtures, was investigated through laboratory microcosm studies, To elucidate the extent of interactions among the used bacterial strains single and mixed cultures were set up. The biodegradation activity of strains in microcosms was examined through viable counts, consumption of phenolic compounds and detecting the presence of catabolic genes by hybridization, During the experiments (30 days) the introduced bacteria remained viable even when the substrates were depleted. The mixture of strains was more effective in the decomposition of phenolic compounds from the natural wastewater as compared with the single culture conditions and the metabolic activity and cell density of each strain were co-ordinated within a specific time scale. The behaviour of strains in the phenolic leachate depended on the growth kinetics of the strains (K,,µ).


2016 ◽  
Vol 74 (6) ◽  
pp. 1398-1408 ◽  
Author(s):  
Kanchariya Phankhajon ◽  
Anchana Somdee ◽  
Theerasak Somdee

An actinomycete strain (KKU-A3) with algicidal activity against Microcystis aeruginosa was isolated from soil in Khon Kaen Province, Thailand. Based on its phenotypic characteristics and 16S rDNA sequence, strain KKU-A3 was identified as Streptomyces rameus. Strain KKU-A3 also exhibited algicidal activity against the cyanobacteria Synechococcus elongatus, Cylindrospermum sp. and Oscillatoria sp. A mathematical and statistical technique was used to optimize the culture conditions and maximize its anti-Microcystis activity. The single factor experiments indicated that glucose and casein were the most effective carbon and nitrogen sources, respectively, and produced the highest anti-Microcystis activity. Response surface methodology indicated that the optimum culture conditions were 19.81 g/L glucose and 2.0 g/L casein at an initial pH of 7.8 and an incubation temperature of 30 °C. The anti-Microcystis activity increased from 82% to 95% under optimum conditions. In an internal airlift loop bioreactor, the removal of M. aeruginosa KKU-13 by the bacterium was investigated in batch and continuous flow experiments. In the batch experiment, KKU-A3 displayed maximum anti-Microcystis activity of 95% at day 7, whereas in the continuous flow experiment, KKU-A3 displayed maximum anti-Microcystis activity of 95% at day 10.


2021 ◽  
Vol 29 (1) ◽  
Author(s):  
Suwapha Sawiphak ◽  
Aroon Wongjiratthiti

Polylactic acid (PLA) is increasingly used in food-packaging production. The screening of PLA-food-packaging-degrading bacteria and optimisation of culture conditions for the PLA-food-packaging degradation by PLA-food-packaging-degrading bacteria were investigated for bioplastic waste management purposes. Only bacterial strain SNRUSA4 exhibited an increase in optical density (OD) in Basal Medium (BM) supplemented with 1.0 g/L of PLA-food-packaging as sole carbon source after 4 weeks of incubation. A weight loss of 7.3% and the rough and porous surface of PLA-food-packaging indicated that SNRUSA4 was a PLA-food-packaging-degrading bacterium. SNRUSA4 was able to degrade pure PLA which was confirmed from the clear zone formation around its colony on emulsified pure PLA agar plate. The 16S rRNA gene sequence of SNRUSA4 showed the similarity with thirteen Bacillus species. Hence, the strain SNRUSA4 was assigned as Bacillus sp. SNRUSA4. Response surface methodology with Box-Behnken Design was used to optimise the culture conditions including yeast extract concentration, initial pH value, temperature and agitation speed for growth and PLA-food-packaging degradation of Bacillus sp. SNRUSA4. The optimal conditions of Bacillus sp. SNRUSA4 was discovered in BM at initial pH value 7.02 with yeast extract concentration of 2.56% and agitated at 205.28 rpm at 31.68°C. Under optimal conditions, the OD of Bacillus sp. SNRUSA4 was up to 1.955, and the different OD between before and after optimisation was up to 1.752. Furthermore, the PLA-food-packaging weight loss also increased from 7.30% to 87.10% indicating that the PLA-food-packaging degradation under optimal conditions was higher than the unoptimised conditions. Therefore, Bacillus sp. SNRUSA4 is an efficient strain for degradation of PLA and PLA-food-packaging.


Author(s):  
Majid Baserisalehi ◽  
Samira Zarezadeh ◽  
Majid Baserisalehi ◽  
Saeed Shoa

Stenotrophomonas maltophilia is an emerging pathogenic non-fermentative Gram-negative Bacillus species. It has caused many nosocomial infections and can be isolated from various hospital wards and healthcare facilities. Research has shown that most of its strains are inherently resistant to many antibiotics and have multidrug resistance. This research intended to determine its occurrence frequency at some Hospitals in shiraz, Iran. The present study was conducted in six months (from early spring to late summer 2019). Clinical samples (Blood, Urine and cerebrospinal fluid (CSF)) collected from 120 patients afflicted with various infections. The samples were transferred to the Laboratory and subjected to microbiological analysis. Identification of the isolates was carried out by phenotypic methods and Stenotrophomonas maltophilia isolates verified using molecular methods. In total, various bacteria were isolated from 84 clinical samples. The isolates were Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Stenotrophomonas maltophilia, Staphylococcus aureus and Pseudomonas aeruginosa. Stenotrophomonas maltophilia was isolated from 17 (20.2%) positive samples and most of them were isolated from blood samples. Our finding indicated that Stenotrophomonas maltophilia isolated more from blood samples follow by CSF sample. In addition, our finding illustrated that Stenotrophomonas maltophilia can be considered as the common nosocomial agent at hospitals in Shiraz, Iran.


2011 ◽  
Vol 175-176 ◽  
pp. 192-196 ◽  
Author(s):  
Li Li Feng ◽  
Jian Fei Zhang ◽  
Hui Luo ◽  
Zheng Li ◽  
Hong Jie Zhang

The paper concentrated on the optimization of the recombinant strain BL21 (DE3)-PE7-Nit. The component of culture medium and the culture conditions were optimized. The optimized medium was: yeast extract 10 g/l, L-glutamate sodium 8 g/l, MgSO4.7H2O 0.7 g/l, Isopropyl-β-D-thiogalactopyranoside 0.3 mmol/L, potassium hydrogen phosphate 0.5 g / L, phosphate Potassium 0.5 g / L and the culture condition was: initial pH 7.0, inoculum 2%. The result showed that the activity of nitrilase prepared with these conditions increased by 130.37 % through optimization.


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