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Polycyclic aromatic hydrocarbons have adverse effects on the organisms, plants, and soil structure. Therefore, they should be removed by an appropriate and effective method. In this study, simultaneous removal of 500 mg/kg(soil) of phenanthrene and pyrene was investigated for the individual and combined application of Tween 80, Triton X-100, and sodium persulfate from the alluvial soil. The results revealed that the maximum removal efficiencies of phenanthrene (94.06 +/- 0.30%) and pyrene (90.07 +/- 0.19%) were observed in the presence of Triton X-100 + sodium persulfate (0.5 M) within 1 hour, respectively. Also, individual application of surfactants and sodium persulfate had efficiencies of less than 80%. It should be noted that the removal of phenanthrene and pyrene followed the first-order kinetic model. Economic evaluations of combined treatment demonstrated that the application of more proportion of Triton X-100 (10000 mg/L) + less proportion of sodium persulfate (0.3 M) is more cost-effective for the remediation of soil in the field study. Based on the results, the combined application of the washing process by Triton X-100 and persulfate oxidant can significantly improve the removal efficiencies and is a promising technique in the remediation of polycyclic aromatic hydrocarbons contaminated soil.

Background: Genetically engineered microorganisms (GEMs) can be used for bioremediation of the biological pollutants into nonhazardous or less-hazardous substances, at lower cost. Polycyclic aromatic hydrocarbons (PAHs) are one of these contaminants that associated with a risk of human cancer development. Genetically engineered E. coli that encoded catechol 2,3- dioxygenase (C230) was created and investigated its ability to biodecomposition of phenanthrene and pyrene in spiked soil using high-performance liquid chromatography (HPLC) measurement. We revised patents documents relating to the use of GEMs for bioremediation. This approach have already been done in others studies although using other genes codifying for same catechol degradation approach. Objective: In this study, we investigated biodecomposition of phenanthrene and pyrene by a genetically engineered Escherichia coli. Methods: Briefly, following the cloning of C230 gene (nahH) into pUC18 vector and transformation into E. coli Top10F, the complementary tests, including catalase, oxidase and PCR were used as on isolated bacteria from spiked soil. Results: The results of HPLC measurement showed that in spiked soil containing engineered E. coli, biodegradation of phenanthrene and pyrene comparing to autoclaved soil that inoculated by wild type of E. coli and normal soil group with natural microbial flora, were statistically significant (p Conclusion: These findings indicated that genetically manipulated E. coli can provide an effective clean-up process on PAH compounds and it is useful for bioremediation of environmental pollution with petrochemical products.

Trifluralin is one of the most widely used herbicides, being accounted as the cause of cancer in human. In the present research, the UV/S2O82− and ZnO/UV processes’ efficiency in the removal of trifluralin was investigated. A lab scale equipped with a UV lamp was applied. The parameters were studied, including initial trifluralin concentration (0.4–1.2 mg/L), contact time (20–60 min), S2O82− concentration (20–60 μM), and ZnO concentration (50–150 mg/L). The remained trifluralin concentration was measured by HPLC. This study proved the trifluralin removal of 92.90 ± 1.6% and 87.91 ± 19.22% for UV/S2O82− and UV/ZnO processes in the best operation conditions (contact time of 60 min, the persulfate concentration of 40 μM, and the ZnO concentration of 100 mg/L). The optimal trifluraline concentrations were 1.2 mg/L and 0.6 mg/L for UV/S2O82− and UV/ZnO processes, respectively. In both processes, the removal efficiency of trifluralin increased significantly with increasing contact time. The findings exhibited that both processes UV/S2O82− and UV/ZnO followed the zero-order kinetic. The electrical energy consumed of UV/S2O82 and UV/ZnO was about 43.95 and 20.41 Kwh/kg, respectively. The results show that UV/S2O82− and ZnO/UV processes were appropriate as the effective treatment method for trifluralin removal. Therefore, it is proposed to study the performance of these processes as an environmentally friendly practice in full scale with real wastewater.

Nowadays, advanced oxidation processes, particularly photocatalyst process and catalytic ozonation by ZnO nanoparticles, are the most efficient method of eliminating pharmaceuticals. The purpose of this study was to compare the efficiency of ultraviolet/zinc oxide (UV/ZnO) and ozone/zinc oxide (O3/ZnO) techniques as advanced oxidation processes in the removal of trimethoprim (TMP) from aqueous solutions. The process consisted of 0.6 g/L of ozone (O3), pH = 7.5 ± 0.5, TMP with a concentration of 0.5–5 mg/L, ZnO with a dose of 50–500 mg/L, 5–30 min reaction time, and 30–180 min contact time with UV radiation (6 W, 256 nm) in a continuous reactor. The high removal efficiency was achieved after 25 minutes when ZnO is used in 1 mg/L TMP under an operational condition at pH 7.5. When the concentration of the pollutant increased from 0.5 to 1, the average removal efficiency increased from 78% to 94%, and then, it remained almost constant. An increase in the reaction time from 5 to 25 minutes will cause the average elimination to increase from 84% to 94%. The results showed that the efficiency of O3/ZnO process in the removal of TMP was 94%, while the removal efficiency of UV/ZnO process was 91%. The findings exhibited that the kinetic study followed the second-order kinetics, both processes. With regard to the results, the photocatalyst process and catalytic ozonation by ZnO nanoparticles can make acceptable levels for an efficient posttreatment. Finally, this combined system is proven to be a technically effective method for treating antibiotic contaminants.

17β-Estradiol (E2) has a significant health risk to humans, even at the ng/L level, and is discharged to the aqueous environment through wastewater. Advanced oxidation processes were proposed as an efficient process for the removal of E2. In this study, a combination of ultraviolet-C (UV-C) and KMnO4 was applied for the removal of E2. Results have shown that the removal efficiency of E2 in pH 4 (acidic condition) was 93.80 ± 0.42%. But, removal efficiency in neutral (7) and alkaline (10) conditions was 78.3 ± 2.12% and 84 ± 0.71%, respectively. The effect of Fe+2, Ca+2, Mg+2, Mn+2, and Fe+3 ions (1 mg/L) was investigated in optimized pH (4). Mn+2, Fe+2, and Ca+2 ions enhanced the removal efficiency to 94.8 ± 0.84%, 95.55 ± 0.07%, and 94.7 ± 0.14%, respectively p > 0.05 , while Mg+2 and Fe+3 ions decreased the removal efficiency significantly to 76.15 ± 1% and 83.91 ± 0.3% p < 0.05 . The efficiency of E2 removal in the presence of 5 mg/L of PAC reduced significantly to 85 ± 4.24% p < 0.05 . Also, humic substances like humic acid, fulvic acid, and a combination of them could enhance the efficiency to 99.87 ± 0.01%, 99.9 ± 0.06%, and 99.93 ± 0.014%, respectively p > 0.05 . The result indicates that the rate of oxidation of E2 is related to the second exponent of the initial concentration of E2 for optimum pH and the presence of all ions. But, in the presence of humic substances, the first-order kinetic reaction was best applicable in describing oxidation of E2. Removal of chemical oxygen demand for E2 after 120 minutes’ of contact time at optimum pH (86 ± 4.2%) demonstrated mineralization of these compounds at acceptable levels. Results presented that the UV-C/KMnO4 process is efficient for the removal of hormones from the aqueous solution.

The delayed healing of episiotomy wound and its associated pain is a major problem in obstetrics. Because green tea has analgesic and wound-healing properties, the present study was conducted to determine the effect of green tea ointment on episiotomy pain and wound-healing. The green tea extract was also standardized by measuring its Phenolic and flavonoid compounds, antioxidant activity, and one of its active components, that is, Epigallocatechin gallate. The present clinical trial was conducted on 99 primiparous women visiting Afzalipour Hospital in Kerman in 2015. The subjects were randomly divided into 3 groups, including a green tea ointment group, a placebo ointment group, and a routine care group. The 2 ointment groups smeared 2 cm of the green tea or placebo ointments onto their sutured area twice daily for a total of 10 days. The severity of pain was assessed in the subjects using the visual pain scale and wound-healing using the Redness, Edema, Ecchymosis, Discharge, Approximation (REEDA) scale before the intervention and on the 5th and 10th days after delivery. To standardize the extract, Epigallocatechin gallate was measured by high-performance liquid chromatography (HPLC). Phenolic and flavonoid compounds, as well as antioxidant activity of the extract were also determined by spectrometry methods. Before the intervention, no significant differences were observed between the 3 groups in terms of their personal and obstetric details (p > .05), the severity of pain (p = .118), and the REEDA score (p = .212). On the 5th and 10th days after delivery, the severity of pain was significantly lower in the green tea group than in the other 2 groups (p < .0001). The mean REEDA score on the 5th and 10th days showed a better and faster healing in the green tea group compared to the other 2 groups (p < .0001). Total content of phenolic and flavonoids contents of green tea were 74.2 mg/g Gallic acid equivalent and 16.3 mg/g Rutin equivalent, respectively, and its antioxidant capacity was 46% of b-carotene. Green tea ointment appears to be effective in relieving episiotomy pain and improving wound-healing in this study. Further studies are recommended to be conducted on the effectiveness and safety of the different doses of green tea ointment.

Bioremediation use to promote degradation and/or removal of contaminants into nonhazardous or less-hazardous substances from the environment using microbial metabolic ability. Pseudomonas spp. is one of saprotrophic soil bacterium and can be used for biodegradation of polycyclic aromatic hydrocarbons (PAHs) but this activity in most species is weak. Phenanthrene and pyrene could associate with a risk of human cancer development in exposed individuals. The aim of the present study was application of genetically engineered P. putida that produce dioxygenase for degradation of phenanthrene and pyrene in spiked soil using high-performance liquid chromatography (HPLC) method. The nahH gene that encoded catechol 2,3-dioxygenase (C23O) was cloned into pUC18 and pUC18-nahH recombinant vector was generated and transformed into wild P. putida, successfully. The genetically modified and wild types of P. putida were inoculated in soil and pilot plan was prepared. Finally, degradation of phenanthrene and pyrene by this bacterium in spiked soil were evaluated using HPLC measurement technique. The results were showed elimination of these PAH compounds in spiked soil by engineered P. putida comparing to dishes containing natural soil with normal microbial flora and inoculated autoclaved soil by wild type of P. putida were statistically significant (p0.05) but it was few impact on this process (more than 2%). Additional and verification tests including catalase, oxidase and PCR on isolated bacteria from spiked soil were indicated that engineered P. putida was alive and functional as well as it can affect on phenanthrene and pyrene degradation via nahH gene producing. These findings indicated that genetically engineered P. putida generated in this work via producing C23O enzyme can useful and practical for biodegradation of phenanthrene and pyrene as well as petroleum compounds in polluted environments.

In the present study, the influence of phenanthrene and pyrene on cytogenetic stability of human dermal fibroblasts using alkaline comet assay was evaluated. The cells were isolated from foreskin samples obtained from healthy male infants and in low passages (P 1–3) were exposed to various concentrations (0.0900, 0.0625, 0.0320, and 0.0066 ppm) of phenanthrene and pyrene. Then, alkaline comet assay was performed to investigate the influence of these compounds on DNA damage and cytogenetic stability of human dermal fibroblasts. In the present work H2O2 treatment was used as a positive control of comet assay to create DNA damages. The analysis of alkaline comet assay parameters by CaspLab software showed the tail DNA% in high concentration (0.0900 ppm) of phenanthrene and pyrene in the exposed cells got increased as compared to normal cells, while head DNA% decreased. Also, similar to positive control (H2O2), DNA damage with long tail comet was observed in high concentration of these compounds as compared to normal cells. The comparison of comet assay parameters specially head DNA% and tail DNA% between each concentrations of phenanthrene and pyrene with other groups (healthy cells and H2O2 treatment) by ANOVA and post hoc Tukey test showed that these parameters were more significantly different (p < 0.05). These results indicated that phenanthrene and pyrene even in low dosage are dangerous and can increase the DNA damage and affect on cytogenetic stability of dermal fibroblasts. These findings suggested that phenanthrene and pyrene could increase the related diseases and risk of skin cancer in exposed individuals.

Background: It is well known that bioremediation or using microorganism enzymes plays an important role in decomposition and changing of oil pollutants and PAH compounds into nonhazardous or less-hazardous substances. The genetically manipulated bacteria like Pseudomonas sp. can enhancement the natural biodegradation activity of polycyclic aromatic hydrocarbons (PAHs) in polluted cities. Pseudomonas putida (P. putida) is a saprotrophic soil bacterium that is found throughout various environments such as soil and freshwater environments. Oil and petroleum industries are important exposure of PAHs in environment that strongly associated with the development of human cancers. Objectives: In the present work, P. putida was genetically manipulated for the biodegradation of oil in spiked soil and its activity was measured using the high-performance liquid chromatography (HPLC) method. Methods: The catechol 2,3-dioxygenase (C23O) encoded gene (nahH) was cloned into pUC18 for generating pUC18-nahH. This recombinant vector was transferred into P. putida, successfully, and both wild type and genetically modified P. putida were inoculated in spiked soil with oil for pilot plan preparation. Then, biodegradation activity of this bacterium on the elimination of phenanthrene and pyrene as an oil indicator in spiked soil were evaluated by the HPLC measurement technique. Results: The results showed the biodegradation of these PAH compounds in oil-spiked soil by genetically manipulated P. putida in both groups (containing autoclaved soil and dish containing natural soil) comparing to the inoculated group by wild type of P. putida were statistically significant (P < 0.05). Finally, confirmatory tests (catalase, oxidase, and PCR) were accomplished on isolated bacteria from spiked soil and were indicated that engineered P. putida was alive and functional by producing the C23O enzyme for biodegradation activity of oil. Conclusions: These findings demonstrated a degradable strain of P. putida that was generated in this study by genetic engineering can be useful to assess biodegradation of PAHs compounds in oil and petrochemical pollutions.

Problem Statement: MTBE is a common pollution of environmental and has become an issue of considerable concern in recent years. It is not readily amenable to remove MTBE by conventional techniques in water treatment. In the present study, the feasibility of the continuous aerobic biodegradation of MTBE, was evaluated in an Up- Flow Fixed Bed Reactor (UFBR). Approach: The UFBR at a constant Hydroulic Retention Time (HRT) of 24 h was used as a biological process that receives the intermediates due to partial oxidation of MTBE. The UFBR coupled to ozonation process as a survey system after a primary operation phase that was necessary for creatory of an initial microbial film on the carriers. Residual concentration of MTBE and its major degradation intermediates were measured by gas chromatography. Aqueous concentration of ozone in the reactor and ozone average concentration in off- gas were determined according to the indigo blue method. The COD reduction and BOD5 to COD ratio were selected as biodegradability indexes. Results: Results showed an effective degradation of MTBE in the coupled ozonation-UFBR continuous flow reactor of ten days of operation time. A partial degradation of MTBE in AOPs increases its biodegradation [The BOD5 to COD ratio increased from lowest (0.01) up to a maximum of 0.72] that corresponds to an ozone consumption of 0.62mg per each mg of COD initially present in the solution. The results showed when m. Mol[MTBE]o/m. Mol(o3) = 0.611, the COD removal efficiency was 89% and as this ratio increased up to 1.25, the of COD removal efficiency decreased to 80%. 46-68% removal of the COD was needed before the mixture was considered biodegradable. The highest removal rate of MTBE, 82.91 mg day-1 achieved through out the UFBR runs (87% removal efficiency, In this study, the removal efficiency of MTBE using integrated-process (ozonation followed biological treatment) was from 78.5-86.5%. In order to determine of biological removal rate of MTBE, another UFBR system used as a blank reactors. Results showed that the efficiency of the COD removal (by stripping with the biological degradation) was 5-8% which implies insignificant biological removal of MTBE without pre-ozonation. Solid produced in the proposed integrated process was 0.27-0.35 kg TSS kg-1 COD removed which is approximately in down range of conventional biological system (0.3-0.5 kg TSS kg-1COD). Conclusion: Present study showed that we can treatment of the polluted aqueous solutions to MTBE without microbial incubation used to integrated process.