Proposed Pathways for Phytodegradation of Phenanthrene and Pyrene in Maize (Zea Mays L.) Using GC-Ms Analysis

2021 ◽  
Author(s):  
Mahdieh Houshani ◽  
Seyed Yahya Salehi-Lisar ◽  
Rouhollah Motafakkerazad ◽  
Ali Movafeghi
Keyword(s):  
Organic Pollutants ◽  
Zea Mays L ◽  
Treatment Time ◽  
Maize Plant ◽  
Degradation Pathways ◽  
The Third ◽  
Ms Analysis ◽  
Polycyclic Aromatic ◽  
Maize Plants ◽  
Gas Chromatography Mass Spectroscopy

Abstract Polycyclic aromatic hydrocarbons (PAHs) are widespread organic pollutants which are persistent in the environment. Biodegradation of PAHs is one of the major mechanisms for their removal from environment. However, unlike microorganisms such as fungi and bacteria, the degradation pathways of organic pollutants in plant systems are not completely clear. This paper displays the possible pathways for the degradation of phenanthrene and pyrene (as two abundant PAHs in the environment) in maize plant. Maize plants were treated by phenanthrene and pyrene and after 7, 14, and 21 days, a number of intermediate compounds were identified using gas chromatography–mass spectroscopy (GC–MS) analysis. The obtained results showed that although maize plant can metabolize both compounds, but the degradation rate of phenanthrene was faster and higher than that of pyrene. The degradation of phenanthrene occurred mainly in the second week, whereas the degradation of pyrene was slower and mostly happened after the third week. Intriguingly, the degradation of both compounds was primarily observed in the roots. The number of identified intermediate compounds was different in the shoot and root and depends on the type of contaminant and treatment time. The most outstanding identified intermediates were quinones, dihydrodiols, phthalate and phenolic compounds which were formed through the cleavage of phenanthrene and pyrene. Accordingly, the probable degradation pathways of phenanthrene and pyrene in maize plants were proposed.

scholarly journals Gluconacetobacter diazotrophicus Pal5 Enhances Plant Robustness Status under the Combination of Moderate Drought and Low Nitrogen Stress in Zea mays L.

2021 ◽  
Vol 9 (4) ◽  
pp. 870
Author(s):  
Muhammad Aammar Tufail ◽  
María Touceda-González ◽  
Ilaria Pertot ◽  
Ralf-Udo Ehlers
Keyword(s):  
Zea Mays ◽  
Plant Growth ◽  
Zea Mays L ◽  
Growth Promotion ◽  
Nitrogen Stress ◽  
Rrna Gene ◽  
N Fixation ◽  
Gluconacetobacter Diazotrophicus ◽  
Maize Plants ◽  
Low Nitrogen

Plant growth promoting endophytic bacteria, which can fix nitrogen, plays a vital role in plant growth promotion. Previous authors have evaluated the effect of Gluconacetobacter diazotrophicus Pal5 inoculation on plants subjected to different sources of abiotic stress on an individual basis. The present study aimed to appraise the effect of G. diazotrophicus inoculation on the amelioration of the individual and combined effects of drought and nitrogen stress in maize plants (Zea mays L.). A pot experiment was conducted whereby treatments consisted of maize plants cultivated under drought stress, in soil with a low nitrogen concentration and these two stress sources combined, with and without G. diazotrophicus seed inoculation. The inoculated plants showed increased plant biomass, chlorophyll content, plant nitrogen uptake, and water use efficiency. A general increase in copy numbers of G. diazotrophicus, based on 16S rRNA gene quantification, was detected under combined moderate stress, in addition to an increase in the abundance of genes involved in N fixation (nifH). Endophytic colonization of bacteria was negatively affected by severe stress treatments. Overall, G. diazotrophicus Pal5 can be considered as an effective tool to increase maize crop production under drought conditions with low application of nitrogen fertilizer.

scholarly journals The Use of Sodium Carbonate—Hydrogen Peroxide (2/3) in the Modified Fenton Reaction to Degradation PAHs in Coke Wastewater

Proceedings ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 44
Author(s):  
Kozak ◽  
Włodarczyk-Makuła
Keyword(s):  
Hydrogen Peroxide ◽  
Organic Pollutants ◽  
Sodium Carbonate ◽  
Uv Light ◽  
Oxygen Demand ◽  
Organic Matrix ◽  
Coke Wastewater ◽  
Polycyclic Aromatic ◽  
Pahs Concentration ◽  
Modified Fenton

The aim of the research was to determine the effectiveness of removing micro-organic pollutants, including PAHs, using the modified Fenton method. The tested material was pretreated coke wastewater, in which the initial chemical oxygen demand (COD) value and initial polycyclic aromatic hydrocarbons (PAHs) concentration were determined. The samples were then subjected to an oxidation procedure. Before the process, the pH was adjusted to 3.5–3.8. Next, the following doses of sodium carbonate—hydrogen peroxide (2/3): 1.2 g/L, 1.5 g/L and 2 g/L, and a constant dose of iron sulphate were added. The next step was exposing the samples to UV light for 6 min and separating the organic matrix from the samples of wastewater. After the tests, the final value of the COD and the final PAHs concentration were determined. The average content of organic pollutants in pretreated coke wastewater determined by the COD index was 538 mg/L, and after the oxidation process, the COD index decreased in the range from 9 to 29%. The efficiency of the degradation of the sum of 16 PAHs was varied and was in the range of 94–97.6%. The research results show that sodium carbonate—hydrogen peroxide (2/3) can be used for the degradation of organic pollutants, such as PAHs, in the modified Fenton process.

scholarly journals Remediation of Anthracene-Contaminated Soil with Sophorolipids-SDBS-Na2SiO3 and Treatment of Eluting Wastewater

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2188
Author(s):  
Wei Li ◽  
Xiaofeng Wang ◽  
Lixiang Shi ◽  
Xianyuan Du ◽  
Zhansheng Wang
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Organic Pollutants ◽  
Aromatic Hydrocarbons ◽  
Contaminated Soil ◽  
Ring Opening ◽  
Single Factor ◽  
Elution Time ◽  
Factor B ◽  
Ring Opening Reaction ◽  
Polycyclic Aromatic

The soil pollution of polycyclic aromatic hydrocarbons (PAHs) is serious in China, which not only affects the living and growing environment of plants and animals but also has a great impact on people’s health. The use of hydrophobic organic compounds to make use of surfactant ectopic elution processing is more convenient and cheaper as a repair scheme and can effectively wash out the polycyclic aromatic hydrocarbons in the soil. Therefore, we mixed sophorolipids:sodium dodecylbenzene sulfonate (SDBS):Na2SiO3 according to the mass ratio of 1:15:150. We explored the influencing factors of high and low concentrations of PAH-contaminated soil using a single factor test and four factors at a two-level factorial design. Then, the elution wastewater was treated by ultrasonic oxidation technology and the alkali-activated sodium persulfate technology. The results showed that: (1) In the single factor test, when the elution time is 8 h, the concentration of the compounded surfactant is 1200 mg/L, the particle size is 60 mesh, the concentration of NaCl is 100 mmol/L, and the concentration of KCl is 50 mmol/L, and the effect of the PAH-contaminated soil eluted by the composite surfactant is the best. Externally added NaCl and KCl salt ions have a more obvious promotion effect on the polycyclic aromatic hydrocarbon-contaminated soil; (2) in the interaction experiment, single factor B (elution time) and D (NaCl concentration) have a significant main effect. There is also a certain interaction between factor A (concentration agent concentration) and factor D, factor B, and factor C (KCl concentration); (3) the treatment of anthracene in the eluate by ultrasonic completely mineralizes the organic pollutants by the thermal and chemical effects produced by the ultrasonic cavitation phenomenon, so that the organic pollutants in the eluate are oxidized and degraded into simple environmentally friendly small molecular substances. When the optimal ultrasonic time is 60 min and the ratio of oxidant to activator is 1:2, the removal rate of contaminants in the eluent can reach 63.7%. At the same time, the turbidity of the eluent is significantly lower than that of the liquid after centrifugal separation, indicating that oxidants can not only remove the pollutants in elution water but also remove the residual soil particulate matter; and (4) by comparing the infrared spectrum of the eluted waste liquid before and after oxidation, it can be seen that during the oxidation process, the inner part of eluent waste liquid underwent a ring-opening reaction, and the ring-opening reaction also occurred in the part of the cyclic ester group of the surfactant, which changed from a ring to non-ring.

scholarly journals The Species Composition and Seasonal Dynamics of Thrips (Thysanoptera) Populations on Maize (Zea Mays L.) in Southeastern Poland

2011 ◽  
Vol 51 (3) ◽  
pp. 210-216 ◽  
Author(s):  
Halina Kucharczyk ◽  
Paweł Bereś ◽  
Zbigniew Dąbrowski
Keyword(s):  
Zea Mays ◽  
Species Composition ◽  
Seasonal Dynamics ◽  
Food Source ◽  
Zea Mays L ◽  
Maize Plant ◽  
Seasonal Abundance ◽  
Immature Stages ◽  
Thrips Species

The Species Composition and Seasonal Dynamics of Thrips (Thysanoptera) Populations on Maize (Zea MaysL.) in Southeastern PolandThrips species composition and seasonal abundance was studied on maize crops during two seasons (2006-2007), in southeastern Poland. Altogether 21 species have been identified, among themFrankliniella tenuicornis(Uzel 1895) andHaplothrips aculeatus(Fabricius 1803) which are a graminicolous species and were eudominants, comprising 96.8% in 2006 and 82.0% in 2007 of all collected specimens. Other species occurred only in low numbers. The frequent and numerous presence ofF. tenuicornisspecies in their immature stages in the samples, confirmed the role of the maize plant as the host.H. aculeatusprobably chose maize as a food source and substitute plant for breeding.

scholarly journals Fate of hydrocarbon pollutants in source and non-source control sustainable drainage systems

2013 ◽  
Vol 69 (4) ◽  
pp. 703-709 ◽  
Author(s):  
Georgios Roinas ◽  
Cath Mant ◽  
John B. Williams
Keyword(s):  
Organic Pollutants ◽  
Chemical Properties ◽  
Pollutant Removal ◽  
Total Petroleum Hydrocarbons ◽  
Source Control ◽  
Storm Events ◽  
Pollutant Loads ◽  
Significant Difference ◽  
Local Roads ◽  
Polycyclic Aromatic

Sustainable drainage (SuDs) is an established method for managing runoff from developments, and source control is part of accepted design philosophy. However, there are limited studies into the contribution source control makes to pollutant removal, especially for roads. This study examines organic pollutants, total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs), in paired source and non-source control full-scale SuDs systems. Sites were selected to cover local roads, trunk roads and housing developments, with a range of SuDs, including porous asphalt, swales, detention basins and ponds. Soil and water samples were taken bi-monthly over 12 months to assess pollutant loads. Results show first flush patterns in storm events for solids, but not for TPH. The patterns of removal for specific PAHs were also different, reflecting varying physico-chemical properties. The potential of trunk roads for pollution was illustrated by peak runoff for TPH of > 17,000 μg/l. Overall there was no significant difference between pollutant loads from source and non-source control systems, but the dynamic nature of runoff means that longer-term data are required. The outcomes of this project will increase understanding of organic pollutants behaviour in SuDs. This will provide design guidance about the most appropriate systems for treating these pollutants.

scholarly journals Identification of DNA of pathogens from Fusarium genus in maize plants (Zea mays L.)

2020 ◽  
Author(s):  
Lidia Tumanova ◽  
◽  
Cristina Grajdieru ◽  
Valentin Mitin ◽  
◽  
...  
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Maize Plants
Sign in / Sign up

Export Citation Format

Share Document