Microbiology
Golshan Shakeri; Abdollah Jamshidi; Saeid Khanzadi; Mohammad Azizzadeh
Volume 8, Issue 1 , March 2017, , Pages 59-65
Abstract
The purpose of this study was to elucidate some factors affecting the growth of Salmonella typhimurium. These factors included Carum copticum essential oil (0%, 0.015%, 0.03% and 0.06%), temperature (25 ˚C and 35 ˚C), pH (5, 6 and 7) and inoculum size (103 and 105 CFU mL-1). Brain heart infusion ...
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The purpose of this study was to elucidate some factors affecting the growth of Salmonella typhimurium. These factors included Carum copticum essential oil (0%, 0.015%, 0.03% and 0.06%), temperature (25 ˚C and 35 ˚C), pH (5, 6 and 7) and inoculum size (103 and 105 CFU mL-1). Brain heart infusion broth was used as the growth medium. There were 48 treatment combinations and the experiment was carried out in triplicate. Growth was monitored by visible turbidity over a 30 days period. A parametric survival model based on the log-normal distribution was used to estimate the most influential factors on the time to detection of Salmonella growth. According to our results, the selected factors significantly affected the growth of Salmonella typhimurium. Furthermore, the final graph demonstrated good agreement between the values predicted by predictive model and the results which were observed in this study. So that a parametric survival model can be a useful and practical tool to predict how the parameters will influence the bacterial growth.
Microbiology
Mojtaba Raeisi; Hossein Tajik; Seyed Mehdi Razavi Rohani; Bektas Tepe; Hossein Kiani; Rahem Khoshbakht; Hesamaddin Shirzad Aski; Hamed Tadrisi
Volume 7, Issue 1 , March 2016, , Pages 7-11
Abstract
Listeria monocytogenes is one of the major causes of infections in developing countries. In this study, chemical composition and anti-listerial effect of the essential oil of Zataria multiflora Boiss. alone and in combination with monolaurin were evaluated at different pH values (5, 6, and 7) and temperatures ...
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Listeria monocytogenes is one of the major causes of infections in developing countries. In this study, chemical composition and anti-listerial effect of the essential oil of Zataria multiflora Boiss. alone and in combination with monolaurin were evaluated at different pH values (5, 6, and 7) and temperatures (5 ˚C and 30 ˚C). Chemical composition of Zataria multiflora Boiss. essential oil was evaluated by gas chromatography-mass spectrometry (GC-MS) analysis. Minimum inhibitory concentration (MIC) of the essential oil and monolaurin were determined using microbroth dilution method and the interactions of essential oil and monolaurinwere determined by the evaluation of fractional inhibitory concentrations (FIC) index.Carvacrol (63.20%) and thymol (15.10%) were found as the main components of the essential oil. The MIC values of the oil and monolaurin at pH 7 and 30 ˚C were measured as 312.50 µg mL-1 and 125.00 µg mL-1, respectively. Combination of monolaurin and Z. multiflora essential oil were found to act synergistically (FIC index < 0.5) against L. monocytogenes under different pH and temperature conditions. Decrease in the pH and temperature values have increased the anti-listerial activity of monolaurin and the essential oil. The lowest MIC value of monolaurin and essential oil was observed at pH 5 and 5 ˚C. According to our results, the oil alone or in combination with monolaurin at low pH and temperature conditions showed a promising inhibitory effect on L. monocytogenes.
Clinical Pathology
Raheleh Assaei; Zohreh Mostafavi-Pour; Naser Pajouhi; Gholam Hossein Ranjbar Omrani; Masood Sepehrimanesh; Fatemeh Zal
Volume 6, Issue 3 , September 2015, , Pages 233-238
Abstract
This work analyzes the effects of Satureja khuzestanica essential oil (SKEO) on the thyroid and antioxidant system, assessed by measuring levels of tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), reduced glutathione (GSH), and glutathione peroxidase (GPx) ...
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This work analyzes the effects of Satureja khuzestanica essential oil (SKEO) on the thyroid and antioxidant system, assessed by measuring levels of tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), reduced glutathione (GSH), and glutathione peroxidase (GPx) activity. Forty adult male Sprague Dawley rats (225 ± 25 g) were divided into five equal groups: one control and four hyperthyroid groups that received placebo, 200 mg kg-1 body weight of vitamin (Vit.) E, 225 mg kg-1 body weight of SKEO, 200 and 225 mg kg-1 body weight of Vit. E and SKEO together, respectively. Hyperthyroidism was induced by administering of L-thyroxin in drinking water. After 30 days of L-thyroxin consumption, serum T3 and T4 levels, TSH, and oxidative stress indices were determined. Significant increase in serum T3, T4 and MDA concentrations with a simultaneous significant decrease in TSH, GSH level and GPx activity were observed in hyperthyroid group (p <0.05). In the treatment groups, SKEO and/or Vit. E can compensate serum MDA elevation and GPx activity reduction. Only, SKEO + Vit. E could compensate the decline of GSH levels in response to hyperthyroidism. Supplementation of SKEO, plus Vit. E as antioxidants is useful in attenuating lipid peroxidation and may potentially benefit hyperthyroid patients.
Majid Aminzare; Javad Aliakbarlu; Hossein Tajik
Volume 6, Issue 1 , March 2015, , Pages 31-39
Abstract
The effect of Cinnamomum zeylanicum essential oil (CZEO) at two concentrations (0.02% and 0.04% v/w) on chemical composition, pH, water activity (aw), lipid oxidation, color stability and sensory characteristics of Lyoner-type sausage stored at 4 ˚C for 40 days was investigated. The moisture content ...
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The effect of Cinnamomum zeylanicum essential oil (CZEO) at two concentrations (0.02% and 0.04% v/w) on chemical composition, pH, water activity (aw), lipid oxidation, color stability and sensory characteristics of Lyoner-type sausage stored at 4 ˚C for 40 days was investigated. The moisture content of the control sample was higher (p < 0.05) than CZEO incorporated samples, while fat, ash and protein content were not affected by adding essential oil. At days 0 and 40, Lightness (L*) and whiteness index (WI) were significantly decreased and total color difference (ΔE) significantly increased (p < 0.05) by adding CZEO. With the exception of first day of storage, redness (a*) and yellowness (b*) were significantly increased and decreased, respectively during the rest of storage (p < 0.05). The pH values were not differing between the control samples and samples containing CZEO (p > 0.05). The water activity content fell in Lyoners with added CZEO during the storage. Incorporation of CZEO retard lipid oxidation process at the end of storage (p < 0.05). Samples containing highest amount of CZEO had higher sensory score compared to control sample. Our results pointed out that CZEO could be used as natural additive for increasing the chemical stability of Lyoner-type sausages.
Abdollah Jamshidi; Saeid Khanzadi; Majid Azizi; Mohammad Azizzadeh; Mohammad Hashemi
Volume 5, Issue 2 , June 2014, , Pages 107-114
Abstract
Black zira (Bunium persicum) is a medicinal plant and spice, naturally grows in Iran. The aim of this study was to investigate the combined effects of different concentrations of Bunium persicum essential oil (EO; including 0, 0.08, 0.16 and 0.24%), three incubation temperatures (15, 25 and 35˚C), three ...
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Black zira (Bunium persicum) is a medicinal plant and spice, naturally grows in Iran. The aim of this study was to investigate the combined effects of different concentrations of Bunium persicum essential oil (EO; including 0, 0.08, 0.16 and 0.24%), three incubation temperatures (15, 25 and 35˚C), three levels of pH (5, 6 and 7 adjusted by hydrochloric acid), and three inoculum size (102, 103 and 104 CFU mL-1) on the growth of Staphylococcus aureus in the brain heart infusion broth. Black zira EO was extracted and its component was identified using gas chromatography-mass spectrometry (GC-MS) analyses. The experiment was carried out in triplicate. Growth was monitored by visible turbidity during a 30-day period. To evaluate effects of explanatory variable on time to detection (TTD) of bacterial growth, parametric survival models based on Log-normal distribution was used. All explanatory variables had significant association with time to detection (p < 0.05). The final model accurately predicted the growth initiation and inhibition of S. aureus.
Mohammad Hashemi; Ali Ehsani; Nima Hosseini Jazani; Javad Aliakbarlu; Razzaqh Mahmoudi
Volume 4, Issue 2 , June 2013, , Pages 123-127
Abstract
Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and investigation of the antibacterial effects of essential oil as well as methanol extract ...
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Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and investigation of the antibacterial effects of essential oil as well as methanol extract from aerial part of Echinophora Platyloba D.C against S. aureus, L. monocytogenes, S. Thyphimurium and E. coli. Chemical analysis using gas chromatography and mass spectrophotometry (GC/MS) showed that ocimene (26.51%), 2,3-Dimethyl-cyclohexa-1,3-diene (9.87%), alpha-pinene (7.69%) and gamma-dodecanolactone (5.66%) were dominant components of essential oil and the main constituents of methanol extract were o-Cymene (28.66%), methanol (8.50%), alpha-pinene (7.42%) and gamma-decalactone (5.20%). The essential oil showed strong antimicrobial activity against tested bacteria, whereas the methanol extract almost remained inactive against gram-negative bacteria. The most sensitive bacteria to essential oil and extract of Echinophora Platyloba D.C were L. monocytogenes and S. aureus. Minimum inhibitory concentration (MIC) values of essential oil against L. monocytogenes and S. aureus were 6250 and 12500 ppm, respectively. MIC of methanol extract against S. aureus and L. monocytogenes was 25000 ppm. Therefore, purifying and evaluation of antibacterial effects of the active substances of the essential oil and methanol extract of this plant for future application as antibacterial agents and food preservatives to combat pathogenic and toxigenic microorganisms is recommended.
Tooraj Mehdizadeh; Hossein Tajik; Seyed Mehdi Razavi Rohani; Abdol Rassol Oromiehie
Volume 3, Issue 3 , September 2012, , Pages 167-173
Abstract
Thyme Essential oils (EO) with antimicrobial and antioxidant properties are widely used in pharmaceutical, cosmetic, and perfume industry. It is also used for flavoring and preservation of several foods. Nowadays, packaging research is receiving a considerable attention due to the development of eco-friendly ...
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Thyme Essential oils (EO) with antimicrobial and antioxidant properties are widely used in pharmaceutical, cosmetic, and perfume industry. It is also used for flavoring and preservation of several foods. Nowadays, packaging research is receiving a considerable attention due to the development of eco-friendly materials made from natural polymers such as starch and chitosan. In this study Thymus kotschyanus EO concentrations ranging from 0 to 2.0%, incorporated in starch-chitosan composite (S-CH) film were used. Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05). Incorporating EO, increased total color differences (DE), yellowness index (YI) and whiteness index (WI) which were significantly higher than control and its transparency was reduced. Our results pointed out that the incorporation of Thymus kotschyanus EO as a natural antibacterial agent has potential for using the developed film as an active packaging.
Ehsan Anassori; Bahram Dalir-Naghadeh; Rasoul Pirmohammadi; Akbar Taghizadeh; Siamak Asri-Rezaei; Safa Farahmand-Azar; Maghsoud Besharati; Morteza Tahmoozi
Volume 3, Issue 1 , March 2012, , Pages 5-11
Abstract
The effect of inclusion of garlic essential oil (EO) at 33, 66 and 100 μg mL-1, raw garlic (GAR) at 5, 10 and 15 mg mL-1 and monensin (MON) at 7.5 μg mL-1 of incubation medium on organic matter digestibility (OMD) was studied with in vitro gas production, ANKOM daisyII and conventional in vitro ...
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The effect of inclusion of garlic essential oil (EO) at 33, 66 and 100 μg mL-1, raw garlic (GAR) at 5, 10 and 15 mg mL-1 and monensin (MON) at 7.5 μg mL-1 of incubation medium on organic matter digestibility (OMD) was studied with in vitro gas production, ANKOM daisyII and conventional in vitro (IVOMD) methods. The material was incubated with sheep ruminal fluid and the experimental design was a completely randomized design. Cumulative gas production was recorded at 0, 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 hours of incubation. Conventional in vitro OMD was determined after 48 hours incubation in acid and pepsin solutions. Samples for DaisyII OMD prepared according to the operating instructions supplied by ANKOM® Tech. Co., Fairport, USA. Compared to in vitro dry matter digestibility (IVDMD), DaisyII and gas production techniques overestimated (P < 0.05) OMD. The addition of EO and MON reduced (P < 0.05) the organic matter (OM), neutral detergent fiber (NDF), acid-detergent fiber (ADF) digestion, and gas production volume. The potential of gas production and rate of gas production for EO and MON were the lowest; however, these variables were higher for GAR supplemented groups. It was concluded that raw garlic could be of great interest for its usage as a modulator of ruminal fermentation.
Ghader Jalilzadeh-Amin; Massoud Maham; Bahram Dalir-Naghadeh; Farshad Kheiri
Volume 2, Issue 2 , June 2011, , Pages 87-96
Abstract
Bunium persicum (Boiss.) is an economically important medicinal plant growing wild in arid regions in Iran. The essential oil of B. persicum (EOBP) was extracted using hydrodistillation. A total of eighteen compounds, representing 96.14 % of the oil was identified by gas chromatography/mass spectrometry ...
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Bunium persicum (Boiss.) is an economically important medicinal plant growing wild in arid regions in Iran. The essential oil of B. persicum (EOBP) was extracted using hydrodistillation. A total of eighteen compounds, representing 96.14 % of the oil was identified by gas chromatography/mass spectrometry (GC/MS).The main compounds were cuminaldehyde (23.04 %), gamma-terpinene (14.48 %), trans-3-Caren-2-ol (12.51 %), acetic acid (10.90 %) and 1,3,8 -p- menthatriene (7.89 %). The effects of 0.1 to 1000 g mL-1 EOBP on ruminal and abomasal smooth muscle of twenty-four healthy sheep and ileum preparations of six rats were assessed in vitro. Ruminal preparations showed relaxation (P < 0.05) when exposed to 100 - 1000 g mL-1 concentrations of EOBP. In the isolated abomasal preparations, EOBP (0.1 - 1 g mL-1) represented a weak spasmogenic effect followed by relaxation. The spontaneous contraction of abomasal smooth muscles was completely abolished with a high dose (1000 g mL-1) of EOBP. Five-minute incubation with EOBP, significantly (P < 0.05) inhibited Ach-induced contraction in higher doses on both tissues. In contrast, rat ileum only showed dose-dependent relaxation effect, and pre-incubated tissues with EOBP, decreased the Ach-induced contraction. The data indicated that the plant contained spasmogenic and spasmolitic constituents. The results also showed that the EOBP profoundly alters gastrointestinal smooth muscle contraction in a dose-dependent and tissue-specific manner.
