Determination of the Equivalent Continuous Sound Level (Leq) in Industrial Indoor Space Using GIS-based Noise Mapping | Author : Faramarz Majidi; Younes Khosravi *; Kamalad-Din Abedi | Abstract | Full Text | Abstract :Background: The present study aimed to replace the integrated sound level meter by the noise map of a work environment in order to estimate the equivalent continuous sound level (Leq) as an important quantity in the noise monitoring of continuous noise sources.
Methods: In this theoretical-experimental study, the grid method was initially used. Sound pressure level (SPL) was measured at the selected stations in three noisy industrial halls. Data analysis was performed in ArcGIS 10.2 software, and the noise map was plotted for each hall separately. Afterwards, the different zones with various SPL intervals were calculated on each noise map, and Leq was determined. For the comparisons, Leq was also calculated using logarithmic equations, based on which the integrated sound level meters were programmed.
Results: The proposed method was highly accurate with the relative error of less than 2%. Furthermore, it decreased the number of mathematical operations 7-15 times compared to the conventional logarithmic method.
Conclusion: According to the results, the available GIS-based software could be accurately replaced by the routine Leq measurement hardware to estimate the Leq spatial noise in noisy industrial environments. |
| Lead Uptake and Its Effects on the Quantitative Indices of C. aronia and J. polycarpus Seedlings in the Environment | Author : Majid Maani; Mir Mozaffar Fallahchai *; Fatemeh Shariati | Abstract | Full Text | Abstract :Background: Removal of mineral pollutants from polluted soil is considered to be major environmental concern in the modern era. The present study aimed to investigate the capability of lead uptake and transfer in various organs of Crataegusaronia and Juniperuspolycarposseedlings and determine the effects of lead accumulation on some of the quantitative indices of these plant species.
Methods: Three-year-old saplings were exposed to various concentrations of lead (zero, 200, 300, and 400 ppm) (No3)2 in the sprouting period in a completely random project in triplicate. Afterwards, the lead uptake value was measured in various organs of C. aronia and J. polycarpus (roots, stems, and leaves) using an atomic absorption device.
Results: The analysis of variance indicated that the features of C. aronia and J. polycarpus saplings (e.g., stem length, basal diameter, and root length) were significantly influenced by lead contamination (P < 0.05). Moreover, the saplings of both varieties had high capacity for lead uptake in their roots, stems, and leaves.
Conclusion: According to the results, the seedlings of C. aronia and J. polycarpus could be used as stabilizing varieties for the removal of lead from polluted soil. It is also notable that J. polycarpus is a more effective lead absorbent compared to C. aronia. |
| Antibacterial Effects of Agicoat Silver Crystalline Nanofibers on Wound Infection Agents | Author : Farzaneh Golabi;Monir Doudi *; Mahboobeh Madani | Abstract | Full Text | Abstract :Background: Drug resistance is a major concern in the treatment of burn wounds. The present study aimed to evaluate the effects of silver crystalline nanofibers on the bacteria isolated from burn wounds at Imam Musa Kazim Hospital in Isfahan, Iran and compare the findings with the samples collected from the skin of healthy adults with standard collection bacteria.
Methods: Agicoat nanosilver dressing was used as the antibacterial agent. The antibacterial effects of the silver nanoparticle solution and silver crystalline nanofibers were assessed using the well diffusion method. In addition, the macrodilution method was applied to determine the MIC and MBC of the silver crystalline nanofibers.
Results: No significant difference was observed in the growth inhibition zone of the silver nanoparticle solution and crystalline nanofibers. Comparison of the effects of silver crystalline nanofibers on wound infection bacteria and healthy skin bacteria (MBC = 0.128 mg/ml) were similar although the effects were more significant than the effects of tetracycline. Moreover, the standard bacterial strains were more sensitive to the nanofibers (MBC= 0.032). The antibacterial properties of the silver crystalline nanofibers reduced after the washing process (10 times; P < 0.001).
Conclusion: According to the results, the silver crystalline nanofibers had significant antibacterial properties on burn wound infection bacteria. |
| Chemical Quality of the Leading Bottled Water Brands Distributed in Gorgan, Iran | Author : Mahdi Sadeghi *;Mojtaba Raeisi;Mina Ghahrechi;Narges Rezaie;Bagher Pahlevanzadehe | Abstract | Full Text | Abstract :Background: With the growing use of bottled water, the continuous research and monitoring of the quality of these products are crucial. The present study aimed to assess the chemical quality of the bottled water distributed in Gorgan, Iran.
Methods: This cross-sectional, descriptive-analytical study was conducted on the samples of bottled water distributed in Gorgan city. Sampling was performed during four months (one sample of each brand obtained every month; total: 36). The chemical quality of the samples was measured using standard methods.
Results: The mean concentrations of nitrate, fluoride, and iron and mean pH of the samples were 12.92 ± 11.05, 0.33 ± 0.12, and 0.64 ± 2.9 mg/l and 6.89 ± 0.39, respectively. Only the physicochemical parameters of pH and iron were significantly higher than the standard values, and the mean levels of the chemical factors were significantly lower than the standard values (P < 0.05).
Conclusion: Consumers expect bottled water to have higher quality as they perceive the product to be a healthier choice than the water supplied by urban distribution networks. High levels of some chemical parameters could adversely affect the health of consumers, especially vulnerable populations, which should be taken into consideration by custodians and authorities. |
| Virulence Characteristics of Yersinia enterocolitica Isolated from Dairy Products in the Northeast of Iran | Author : Milad Tavassoli;Abdollah Jamshidi;Fahimeh Movafagh;Asma Afshari * | Abstract | Full Text | Abstract :Background: Yersinia enterocolitica (Y. enterocolitica) has a wide range of clinical, animal, food, and water sources. Most studies have indicated that food is the most common source of this organism. The present study aimed to evaluate the virulent genes of Y. enterocolitica isolated from dairy products in Iran.
Methods: The virulence of Y. enterocolitica biotypes was investigated, which was isolated from 38 cheese and 33 raw milk samples in the northeast of Iran. In total, six virulence-related genes were evaluated, including ail, inv, yadA, myfA, ystA, and ystB in 1A, 1B, and 5 Y. enterocolitica biotypes.
Results: In the isolates of the 1A biotype, ystB was the most frequent gene (86.95% and 38.46% in cheese and raw milk, respectively). In the 1B biotype, the most frequently isolated gene was yadA (92.30% and 66.66% in cheese and raw milk, respectively). In all the isolates, the least frequently isolated gene was ail, followed by myfA.
Conclusion: According to the results, the presence of virulence genes in the Y. enterocolitica strains isolated from dairy products suggested that these strains could pose significant risk to public health if dispersed in susceptible human population. |
| Antimicrobial Effects of the Nanoemulsion of Rosemary Essential Oil against Important Foodborne Pathogens | Author : Hassan Hassanzadazar *;Samira Yousefizadeh;Azadeh Ghafari;Mehdi Fathollahi;Majid Aminzare | Abstract | Full Text | Abstract :Background: The purpose of this study was to determine the effect of rosemary essential oil (REO) nanoemulsion against some important food borne pathogens.
Methods: Antibacterial effects of REO and REO nanoemulsion were determined using Agar disc diffusion, Broth microdilution and Steam phase diffusion methods against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Shewanella SP, Listeria monocytogenes and Salmonella enteritidis.
Results: Antibacterial effect of REO and REO nanoemulsion was increased with concentration enhancing of REO. There was no significant antibacterial activity in the effectiveness of nanoemulsion on the studied bacteria in comparison with REO in both disk diffusion and steam phase diffusion methods. MIC and MBC analysis of REO and prepared REO nanoemulsion showed that REO and its nanoemulsion have inhibited all studied bacteria. REO showed better inhibitory effects. REO and nanoemulsion of rosemary essential oil have the greatest effect on Shewanella SP., L. monocytogenes, S. aureus, S.enteritidis, E. coli and P. aeruginosa, respectively.
Conclusion: In total, it can be said that REO and its nanoemulsion are desirable to inhibit the growth of food borne pathogens and can be a good choice as antimicrobial agents in food industry to enhance safety and extend foods’ shelf life. |
| The Antibacterial and Antioxidant Effects of Clove (Syzygium aromaticum) and Lemon Verbena (Aloysia citriodora) Essential Oils | Author : Mahzad Hosseini;Abdollah Jamshidi *;Mojtaba Raeisi;Mohammad Azizzadeh | Abstract | Full Text | Abstract :Background: The Study aimed to investigate the chemical composition, antimicrobial effects, and antioxidant properties of clove and lemon verbena essential oils (EOs).
Methods: The chemical composition of the EOs was identified using gas chromatography/mass spectrometry (GC/MS). In addition, the antibacterial effects of EOs against seven important foodborne bacteria were assessed using the disk-diffusion, agar well-diffusion, and broth microdilution assays. Evaluation of the antioxidant properties of the EOs was carried out using DPPH, ß-carotene-linoleic acid bleaching, and reducing power assay.
Results: All the tested bacteria demonstrated susceptibility to EOs, with the highest susceptibility observed in Bacillus cereus to the clove EO in the agar disk-diffusion test. Moreover, Shigella dysenteriae was identified as the most sensitive bacterium to the lemon verbena EO. Salmonella typhimurium was the most resistant bacterium to both EOs. In the agar well-diffusion test, Pseudomonas aeruginosa and S. typhimurium had the lowest sensitivity to the clove and lemon verbena EOs, respectively. Although both EOs exhibited significant antioxidant capacity, the lemon verbena EO showed higher antioxidant activity in all the tests, with the exception of ß-carotene-linoleic acid bleaching test.
Conclusion: Clove and lemon verbena EOs could be regarded as potential sources of natural antioxidant and antimicrobial agents in food processing. |
| Chemical Composition and Antibacterial Activity of the Emulsion and Nano-emulsion of Ziziphora clinopodioides Essential Oil against Escherichia coli O157:H7 | Author : Saeid Khanzadi *;Asghar Azizian;Mohammad Hashemi;Mohammad Azizzadeh | Abstract | Full Text | Abstract :Background: The present study aimed to determine the chemical composition and in-vitro antibacterial activity of Ziziphora clinopodioides essential oil (ZCEO).
Methods: The chemical composition of ZCEO was determined using gas chromatography-mass spectrometry (GC-MS) analysis. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were calculated using the microwell dilution assay to assess the antibacterial effects of ZCEO emulsion and nano-emulsion on E. coli O157:H7.
Results: A yield of 1% (w/w) was identified for ZCEO isolation and pulegone (58.78%), menthone (1.15%), and isomenthone (9.91%) as the key components of ZCEO phytochemicals. The MIC values of the ZCEO emulsion and nano-emulsion were 0.8 and 0.025 mg/ml, respectively, and the MBC values were estimated at 1.6 and 0.05, respectively.
Conclusion: It is recommended that the nano-emulsion of ZCEO be applied as a potential source of natural preservatives in food industries. |
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