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101.
Forty samples of dried vine fruit (raisin, n?=?22; currant, n?=?18) were collected in 2009?C2011 from the Iranian market. Aflatoxins (AFs) and ochratoxin A (OTA) were determined in these samples after immunoaffinity column clean-up by high performance liquid chromatography (HPLC) with fluorescence detection. The limit of quantification (LOQ) for AFs B1. B2, G1, G2, and OTA were 0.62, 0.50, 0.70, 0.40, and 0.42?ng/g, respectively. AFB1 was found in one sample of raisin (0.64?ng/g) and in two samples of currant (0.20 and 0.63?ng/g). AFB2 (0.33?ng/g) and AFG2 (0.49?ng/g) were found in 2 samples of currant. OTA was detected in 3 of the 22 samples of raisin (mean 2.21?ng/g) and in one sample of currant (2.99?ng/g). The results show that in AFs and OTA levels are well below the regulatory limits both of the European Union and of Iran.  相似文献   
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Badab-e Surt spring is a travertine spring that has low to moderate levels of salt, so it is a good model for isolating moderately halophilic bacteria and investigating the relationship between microbe and environment. For isolating bacterial strains, water and sediment samples were collected from different springheads of the Badab-e Surt spring. Among the 171 bacterial isolates, 110 strains were halophiles. According to comparative partial 16S rRNA sequence analysis, the selected halophilic gram-positive and gram-negative strains were identified as members of the genera: Roseovarius, Labrenzia, Erythrobacter, Erythromicrobium, Massilia, Marinobacter, Halomonas, Shewanella, Pseudomonas, Flavobacterium, Bacillus, Brevibacterium, Staphylococcus, Microbacterium, Kocuria, and Streptomyces. To investigate mineralization, potential strains were screened by the culturing method, and then analyzed with a polarizing and scanning microscope. Five strains, Bss-11a, Bss-3, Bsw-1c1, Bsw-28d, and Bsw-39b, had potential for the mineralization of calcite that very closely resembled species Bacillus cohenii DSM 6307T, Labrenzia aggregate IAM 12614T, Bacillus safensis FO-036bT, Marinobacter flavimaris SW-145T, and Marinobater adhaerens HP15T, respectively.  相似文献   
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Satureja khuzistanica is an endemic herb growing wild in Iran with interesting pharmacological and biological properties. Here, as an initial step of the domestication process, the variability of phytochemical and morphological traits among 69 individuals of eight natural populations of the plant was studied. The investigated characteristics were the essential oil content and composition, the rosmarinic acid (RA) content, and the leaf and flower morphologies. The Abdanan and Kaver populations showed the highest oil contents. The characterization by GC-FID and GC/MS analyses of the oils revealed that all 69 sampled individuals had carvacrol as the main component with very high contents (89.59-95.41%). The content of RA of the MeOH extracts of S. khuzistanica showed a high level of variability (coefficient of variation (CV) 50.0%) ranging from 0.59% (w/w) in the Paalam population to 1.81% (w/w) in the Abdanan population. The peduncle length and the leaf surface area (CVs of 47.39 and 47.21%, resp.) were the most variable morphological characteristics among the examined populations. The high level of phytochemical and morphological variability among the studied populations suggests a breeding approach during the domestication, to gain new, promising, and homogenous cultivars, attractive for the industry and agriculture.  相似文献   
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In this study 97 soil samples from different soil ecosystems were collected. The initial screening was performed on modified glycerol arginine agar (MGAA) to isolate common actinomycetes and on modified MGA-SE (MMGA-SE) to isolate rare actinomycetes. Sixty-seven isolates potentially producing extracellular phytate-degrading activity were identified. The potential to dephosphorylate phytate was confirmed in liquid culture for 46.3 % of the isolates. 12 strains were selected for a direct determination of their phytate-degrading capacity. The results highlighted that the selected isolates produced extracellular phytate-degrading activity; however their capacity in InsP(6) degradation was different. In addition the fermentation medium had an effect on the extent of phytate degradation. Some enzymatic properties of the phytases from isolate No. 43 and isolate No. 63 were determined after obtaining phytase-enriched samples. The enzymes had maximum phytate-degrading capability at 55 °C and pH 5 (isolate No. 43) and 37 °C and pH 7 (isolates No. 63), respectively. Due to their properties, the phytase of isolate No. 43 behaves like a histidine acid phytase, whereas the phytase of No. 63 showed similar enzymatic properties to the phytase of lily. To our knowledge, the results from this study demonstrated for the first time that actinomycetes produce extracellular phytate-degrading activity. By 16SrRNA sequencing, the more closely studied phytase producers were identified as Streptomyces sp. Isolate No. 43 showed 98 % identity to Streptomyces alboniger and S. venezuelae, while isolate No. 63 exhibited 98 % sequence identity to S. ambofaciens and S. lienomycini.  相似文献   
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Cinnamon (Cinnamomum verum and C. cassia) is a medicinal plant, widely-used as a culinary spice. It possesses various therapeutic effects and can slow down the progression of neurological disorders impressively. In this article, the effects of hydro-alcohol extract and essential oil of C. verum and C. cassia and its main bioactive component cinnamaldehyde, has been examined on 6-OHDA-exposed PC12 cells as an in vitro model of Parkinson's disease. The cytotoxicity and cell apoptosis has been induced by 6-OHDA in PC12 cells. The protective effect was determined by measuring cell viability, the amount of reactive oxygen species (ROS), and apoptosis. Cell viability and apoptosis were assessed using resazurin assay, flow cytometry of propidium iodide (PI) stained cells, and western blot analysis. 6-OHDA resulted in the death and apoptosis of cells while, pretreatment with the extract and essential oil of C. verum and C. cassia at 20 µg/ml and cinnamaldehyde at 5 and 10 µM for 24 h could significantly increase the viability (p?<?0.001), and decrease ROS content (p?<?0.05). Pretreatment with the extracts increased survivin and decreased cyt-c whereas, pretreatment with the essential oil decreased cyt-c, increased survivin, and reduced P-p44/42/p44/42 levels to a level near that of the related control. The extract and essential oil of C. verum and C. cassia can be effective against 6-OHDA cytotoxicity. It is suggested that, the synergistic effects of cinnamaldehyde and other components of extract and essential oil promote cinnamon’s medicinal properties.

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