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Showing 8 results for Phenol
M Entezari, M Hekmati, S Heidari Kashl, A Azin, Sh Hekmat, A Barkat, R Shiri Haris,
Volume 20, Issue 4 (2-2013)
Abstract
Introduction: The lifespan of organic coa-tings is reduced in outdoor applications by attacks of solar radiation, oxygen and atom-spheric pollutants. Degradation of coating and recoating introduce pollutants into the environment. For solvent based coatings like alkyd paints, volatile organic comp-ounds (VOC) are the main source of pollut-ion. Undesirable mechanical, physical and chemical consequences of the resulting degradation can be substantially restricted by properly selected photo stabilizers.
Materials & Methods: Carotene than carr-ots extracted by ethanol and 2 - propanol at a temperature of 60 º C in 4-2 hours. In this regard, samples and control were analyzed by UV spectroscopy and results were compared with samples after past 30 days exposure on the UV sunlight.
Findings: Beta carotene acts like a subs-tance against UV light and can increase the resistance of the material to be used as anticancer drug however it's not able to do the task by itself. In a view, beta carotene is counted as a powerful anti-oxidant material. If such material is increased in UVAs, the UV absorbing quality will be increased. Such work is considered a big advantage in anti-cancer drugs. Tautomerization and co-njugation in phenols makes them to be con-sidered as important UV absorbers and eff-ective class of UV-absorbers.
Discussion & Conclusion: In this paper we have investigated the effect of phenolic UVAs on increasing UV absorbing quality in beta carotene, viable cancer cell numbers or MTT test was also performed
Salman Ahmadyasbchin, Ayatollah Nasrolahi Omran, Arman Rostamzad, Naser Jafari,
Volume 21, Issue 7 (2-2014)
Abstract
The heavy metal pollution has become one of the most important environmental problems. Heavy metals are the most important environmental pollutants, especially for human health and aquatic systems are a serious threat. Iranian Research Organization for Science and Technology of yeast Saccharomyces carlsbergensis PTCC 5051, and received as a lyophilized culture YEDPA environment and then the proliferation of malt extract broth is used. The effects of pH, temperature, kinetics and isotherm of lead on metal uptake were evaluated by the SC. Absorption maximum at about pH 5 the optimum temperature was 25 degrees Celsius. A kinetic study showed that batch biosorption of lead to rapid removal by the biomass of Saccharomyces was the first test was done in less than 30 minutes. Method using FT-IR, surface functional groups of fungi were identified. With active and passive absorption of lead by Saccharomyces has revealed more attracted by the yeast is active. With yeast and control yeast on the autoclave, the pre-treated with sodium azide and 2 and 4 DNP nitro phenol showed that claims of capturing, respectively, 0/68, 0/12, 0/44 and 0/48 mmol g was obtained. Results showed that, even using the passive yeast are suitable for the absorption of lead . Keywords: Biosorption, lead, Saccharomyces carlsbergensis, 2, 4-Dinitrophenol, Sodium azide
Mohamad Reza Samar Ghandi, Mohamad Taghi Samadi, Jamal Mehralipoor, Roya Harati,
Volume 24, Issue 1 (4-2016)
Abstract
Introduction: Phenol and Cadmium are of common components used in industries wastewater such as petroleum refining, petrochemicals, and pesticides. The aim of this study was simultaneous removal of Cadmium and Phenol from aqueous solution by using Titanium dioxide nanoparticles in nano-photocatalytic process UV/TiO2.
Materials & methods: This experimental study in lab-scale batch was accomplished by using photo-reactor equipped with a 125 W low-pressure mercury vapor lamp and with Wavelength 247.3 nm and intensity 1020 µW/cm2 and emphasis on the effect of various parameters; such as pH (3-11), nano-particles doses (0.25-3 g/L) and Phenol, Cadmium at a concentration of (5-20 mg/L), presence of Format and removal rate of COD was investigated.
Findings: The obtained results showed that optimum pH in the removal of Cadmium and phenol is 7. The presence of each of pollutants has positive role in increasing the removal of other contaminants. The presence of Phenol cause increase removal of Cadmium and presence of Cadmium cause increase removal of Phenol. Removal efficiency of COD by UV/TiO2 process after 120 min was obtained %71.4. Obtained results of experimental kinetics showed that Phenol and Cadmium removal kinetics was followed (by both photocatalytic processes) of equations zero-order and pseudo-first order, respectively. By changing in conditions of experiment, the degradation efficiency decreases in this process.
Discussion & Conclusions: The result of this study showed that nano-photocatalytic process UV/TiO2 in pilot scale has high efficiency as an effective method in simultaneous removal of phenol and Cadmium from aqueous solution.
Dr Mohammad Malakootian, Miss Hakimeh Mahdizadeh,
Volume 25, Issue 1 (5-2017)
Abstract
Introduction: 4-chlorophenol is a toxic and corrosive matter which the Environmental Protection Agency of America (EPA) has reported as one of the priority pollutants. This study is carried out to investigate the efficiency of multi-walled carbon nanotubes oxidized with a mixture of H2SO4/HNO3 in removal of 4-chlorophenol from aqueous solutions.
Materials & methods: This research was an experimental study which was conducted in the first half of 1393 in environmental health engineering research center, Kerman University of medical sciences. Firstly, multi-walled carbon nanotubes were oxidized with a mixture of H2SO4/ HNO3 then effective parameters on phenol removal from aqueous solutions such as the initial concentration of 4-chlorophenol, contact time, amount of adsorbent and pH were studied. Actual wastewater of coal-cleaning with predetermined quality was also studied. SPSS-16 software and Pearson correlation were used for data analysis.
Findings: Removal efficiency of 4-chlorophenol in optimum conditions including pH= 7, contact time= 10 minutes, amount of adsorbent= 0.3 g, the initial concentration of adsorbent= 15 mg/L, was 91.8 percent. Study of the kinetic and isotherm equations showed that the process of adsorption followed the second order kinetic and Freundlich isotherm.
Discussion & conclusions: Multi-walled carbon nanotubes oxidized with a mixture of H2SO4/HNO3 was a good adsorbent for removal of 4-chlorophenol from aqueous solutions and is able to remove this matter from the actual sewage with an efficiency rate equal to 78%, so it can be used as an effective adsorbent for treatment of polluted water and wastewater.
Pro Mohammad Malakootian, Khadije Golmirzaee, Mahshid Loloei,
Volume 25, Issue 2 (7-2017)
Abstract
Introduction: 4-chlorophenol is one of the common contaminants in wastewater resulted from chemical and petrochemical industries. This matter is resistant to biodegradation due to presence of chlorine and benzene ring in its structure. Various methods have been used to remove this contaminant from environment but the advanced oxidation techniques are more capable. In this study, proxone method (hydrogen peroxide plus ozone) was investigated to remove, 4-chlorophenol.
Materials & methods: This study is experimental and some parameters including pH, 4-chlorophenol initial concentrations, contact time, and the concentrations of oxidant (H2O2) during proxone process were investigated to remove 4-chlorophenol. All tests were conducted on actual solution (effluent of coal cleaning plant). Microsoft Office Excel 2013 software and SPSS 15 were used for data analysis.
Findings: The maximum removal efficiency of 4-chlorophenol at optimum condition (including pH=9, contact time=30 minutes, ozone concentration=0.09 g/hr, the initial concentration of 4-chlorophenol=100 ppm, the optimum concentration of H2O2=0.001 molar) were achieved 96.8% and 92.65% for synthetic and actual solution, respectively.
Discussion & conclusions: Advanced oxidation, according to Peroxone method is a suitable way to remove 4-chlorophenol and is able to remove this material from actual wastewater with efficiency of 92.65%. So, this method can be used for water purification and contaminated wastewater with this pollutant.
Roya Karamian, Mostafa Asadbeigy, Siamak Yari,
Volume 26, Issue 4 (11-2018)
Abstract
Introduction: Acute alcohol consumption leads to induction of lipid peroxidation in renal tissues, but its chronic consumption has moderate effects on biochemical and histological characteristics of this organ. Antioxidants have protective effects against ethanol-induced oxidative stress and tissue injury. The aim of this study was to assess antioxidant activity of Glycyrrhiza glabra leaf and stem extracts and the protective effect of its leaf extract on ethanol-induced nephrotoxicity.
Materials & methods: Total phenol and flavonoid contents of leaf and stem extracts of G. glabra were measured by Folin Ciocalteu and AlCl3 assays, respectively. Antioxidant activity of both extracts was assessed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. In addition, protective effect of the leaf extract was assessed using biochemical and histological analyses of renal tissues of male Wistar rats, which were divided into four groups including group 1 or control (received 1 ml distilled water daily), group 2 or ethanol group (received 1 ml of 50% ethanol daily), group 3 or ethanol + leaf extract group (received 1 ml of 50% ethanol + 500 mg/kg leaf extract daily), and group 4 (received 500 mg/kg of leaf extract daily). All treatments are performed through intragastric administration. Biochemical and histological analyses were used for the evaluation of nephrotoxicity. For histological study, the samples were stained with Hematoxylin-Eosin and examined by light microscopy. Finally, all the data were analyzed by SPSS (Ver. 20) and grouped by Duncan's Multiple Range Test at P <0.05 level.
Findings: There was no significant difference between total phenol contents of the stem and leaf extracts. However, the stem extract showed a higher total flavonoid content than the leaf extract. Also, both the extracts showed higher antioxidant activities (86-93%) than that of ascorbic acid (71%). Results from biochemical analysis indicated a significant increase in superoxide dismutase (SOD) activity and H2O2 content in the renal tissues of ethanol-treated rats in comparison with other groups; however, there were no significant changes in total protein and malondialdehyde (MDA) contents. Results from histological examination showed that alcohol consumption intensity injured kidney tissues, which was effectively moderated by the studied extract.
Discussion & Conclusions: Results from the present study showed that G. glabra extract has biological activity and can be used in future as a new natural antioxidant in food and drug industries.
Mohamad Ahim Forouzeh, Abolfazl Sharifian, Hasan Yeganeh, Hoda Shahiri Tabarestani,
Volume 30, Issue 4 (10-2022)
Abstract
Introduction: Tussilago farfara L. is a perennial forb belonging to the Asteraceae family. The leaves and flowers of this plant have medicinal properties, and its essential oil has been used for the treatment of dry coughs and inflammation of the mouth, throat, and respiratory tract. This study aimed to assess some phytochemical characteristics of Tussilago farfara L. and compare changes in this plant at different altitudes.
Material & Methods: To investigate the changes in the amount of the effective substance of the studied plant in the altitude gradient, altitude classes of 1100-2600 meters were considered in Golestan province, Iran, considering the presence and abundance of the species. In each phenological stage (before and after flowering time), plant samples were randomly collected in each altitude class and transferred to the laboratory. Total phenol content and flavonoid content were measured using the Folin-Ciocalteu and aluminum chloride methods, respectively. The antioxidant activity of the methanolic extract was also evaluated using the DPPH (2,2-Diphenyl-1-picrylhydrazyl) reagent.
Findings: The results showed that the highest amounts of total phenol content, flavonoids, and antioxidant activity were observed at altitudes above 2200 meters, and there was a significant difference in plants (Tussilago farfara L.) grown in different altitudes in terms of phytochemical properties. Based on the comparison of phytochemical properties of this plant in different phenological stages, the highest content of total phenol and flavonoids were observed in the phonological stage of flowering and the highest (42.08%) antioxidant activity of leaves was observed in the vegetative stage.
Discussion & Conclusion: The results of this study can help activists in the field of medicinal plants to determine the appropriate height range and phenological stage in harvesting the leaves of this plant to achieve the highest levels of phenol content, flavonoids, and antioxidant activity.
Afsoon Rezaie Allolo, Mohsen Sanikhani, Aziz Alah Khairy, Maliheh Yaghoobi,
Volume 31, Issue 6 (2-2024)
Abstract
Introduction: The extraction of chemical compounds from plants is influenced by various factors, such as methodology and duration of extraction, sample preparation, and the type and concentration of solvent used. This study was performed to investigate the effect of extraction time and type of solvent on the contents of phenolic compounds, flavonoids, and antioxidant activity of Digitalis purpurea L. plant.
Material & Methods: An experiment based on a completely randomized design in a factorial arrangement with three replications was conducted at the Horticulture Laboratory at the University of Zanjan, Zanjan, Iran, in 2021. The experimental treatments included two levels of extraction duration (24 and 48 h) as the main factor, and two levels of methanol, ethanol, and acetone solvents (100% and 80%), compared with the control (distilled water), as sub-factors. Extraction of purple foxglove leaf powder was done by macerating 24 or 48 h using two levels of methanol, ethanol, or acetone as solvents (100%, 80%, and distilled water for the control). Evaluation of phenolic compounds, flavonoids, and antioxidant activity was performed. The resulting data were analyzed in SAS software version 9, and mean comparisons were performed by Duncan's Multi-Range Tests at the 1% and 5% probability levels. To determine the correlation between parameters, Pearson's correlation coefficient was checked using SPSS version 20 software.
Results: The results showed that there was a significant difference between 24 and 48 h of maceration to extract chemical compounds (P<0.01). The highest amounts of total phenol (24.75 mg GAE/g dw) and antioxidant activity (71.36%) were obtained in 80% acetone extract, and the maximum flavonoid content (6.03 mg Q/g dw) was achieved in 80% ethanol and 48 h maceration time. Generally, increasing the maceration time from 24 h to 48 h caused a significant rise in the extraction of phenolic compounds, flavonoids, and antioxidant activity. Moreover, there was a positive correlation between flavonoid content (P=0.86) and phenolic content (P=0.82) with antioxidant activity.
Discussion & Conclusion: According to the results, increasing the extraction time and also utilizing hydroalcoholic solvents were more effective in extracting these compounds than pure alcohols.
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