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In order to evaluate the effect of Artemisia sieberi extract from different habitats on the shelf life of Iranian white cheese, this research was conducted in 2022 in the research laboratory of Qom University, Iran. A factorial experiment was conducted based the completely randomized design, and cheese in terms of chemical and microbial characteristics in the conditions of no extract (control) and the use of extract containing 1% of the weight of the fresh material of A. sieberi from three habitats of Venan, Tajkhatun and Abbas Abad was checked on the 1st, 1 5 th and 30th. The results showed that the population of cheese microorganisms increased with the increase of the storage period, and the extract of Venan better controlled the population of microorganisms than other extracts. The amount of pH and protein in the dry matter decreased with the increase of the storage period, and the amount of moisture, salt, fat, dry matter, phenol and antioxidant activity increased. Venan extract increased the quality and shelf life of cheese more than other extracts, which may be due to the higher amount of total phenol in Venan extract compared to other extracts. In general, the extract of Artemisia sieberi significantly increased the shelf life and quality of cheese, and with further studies, the extract of this valuable plant can be used to increase the shelf life and quality of food products, especially dairy products. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the conformity or non - conformity of traditional liquid Kashks supplied in Hamedan city with the national standard of Iran. To carry out this research, Kashk samples from manufactures of traditional dairy products (in Hamedan city) were prepared in two stages and transferred to the food quality control laboratory for examination. Microbial population (total count, staphylococcus, coliform, and mold -yeast), chemical properties (total solids %, salt, acidity, and pH) and color parameters including lightness (L*), redness (a*) and yellowness (b*) of tradition Kashk was examined and after statistical analysis, their results were reported. The average number of microorganisms (total count), staphylococcus and coliform in the Kashk samples were 7.28 Log cfu/g, 4.09 Log cfu/g, and 1.64 Log cfu/g, respectively. According to the national standard of Iran, the maximum number of mold and yeast in liquid Kashk should be 2 Log cfu/g, but the average number of mold and yeast in the prepared Kashks were 7.39 Log cfu/g, which is much higher than the specified standard for this product. The average of total solid of Kashks were 21.15%, which was less than the defined standard (at least 25%) for it. Also, the average of moisture, salt, acidity, and pH of examined Kashks in this research were 78.85%, 1.98%, 1.90%, and 4.09 respectively. Color parameters of Kashk samples were examined and the average color indexes including lightness, redness, and yellowness of the samples were 84.52, 1.53 and 6.43 respectively. Of course, no statistically significant difference was observed between the color indexes values of the samples (p>0.05). [ABSTRACT FROM AUTHOR]

A significant proportion of the Earth surface is covered by deserts. Despite the stressful environmental conditions, deserts can host diverse microbial populations, especially extremophiles. Due to their remarkable adaptive capabilities, extremophiles have been used in biotechnology and medicine. Understanding microbial diversity in arid environments offers also potential sources of new natural bioactive metabolites. The Lut Desert, located in the eastern part of Iran, is one of the driest and hottest deserts around the world. It presents a collection of unique natural phenomena and geological records. In this review, we describe the previous efforts to show the microbial diversity in the Lut Desert and highlight their promising applications. [ABSTRACT FROM AUTHOR]

Phenols are toxic products derived from a wide range of industrial activities and the entry of these contaminants into the environment is seriously hazardous for both human and aquatic ecosystems. This study presents the use of a phenol-degrading consortium surrounded in an innovative "Small Bioreactor Chambers" (SBCs) along with biostimulation for phenol bioremediation from contaminated groundwater. To investigate the effect of biostimulation, synthesized-calcium peroxide (Ca02) nanoparricies were applied. The phenol-degrading consortium, was successfully isolated froni a water well located in Iran. The highest growth rate and phenol degradation of the ph100-consortium were observed at 15 °C and pH 7.5 in the presence of 500 mg·L-1 of powdered CaO2 and 100 mg·L-1 of phenol as a sole source of carbon. Next-generation sequencing (NGS) analysis of the consortium revealed that Proteobacteria and Bacteroidetes with 75.3% and 16.2% relative abundance were the dominant phyla in the ph100-consortium, respectively. Experimental results indicated that 100% of the contaminant (100 mg·LF) was successfully removed from groundwater using encapsulated CaO2 within 60 days with the negligible negative impacts on the microbial population. Furthermore, the highest biodegradation percentage were achieved during incubation of SBCs a medium supplemented with 500 mg·L-1 CaO2 Powder in 25th days of experiment. These results provide certain evidence for a successful simultaneous application of biostimulation and bioaugmentation processes through SBCs for contaminated water treatinent. [ABSTRACT FROM AUTHOR]

Background: To initiate fecal and oral collections in prospective cohort studies for microbial analyses, it is essential to understand how field conditions and geographic differences may impact microbial communities. This study aimed to investigate the impact of fecal and oral sample collection methods and room temperature storage on collection samples for studies of the human microbiota. Results: We collected fecal and oral samples from participants in two Iranian cohorts located in rural Yazd (n = 46) and urban Gonbad (n = 38) and investigated room temperature stability over 4 days of fecal (RNAlater and fecal occult blood test [FOBT] cards) and comparability of fecal and oral (OMNIgene ORAL kits and Scope mouthwash) collection methods. We calculated interclass correlation coefficients (ICCs) based on 3 alpha and 4 beta diversity metrics and the relative abundance of 3 phyla. After 4 days at room temperature, fecal stability ICCs and ICCs for Scope mouthwash were generally high for all microbial metrics. Similarly, the fecal comparability ICCs for RNAlater and FOBT cards were high, ranging from 0.63 (95% CI: 0.46, 0.75) for the relative abundance of Firmicutes to 0.93 (95% CI: 0.89, 0.96) for unweighted Unifrac. Comparability ICCs for OMNIgene ORAL and Scope mouthwash were lower than fecal ICCs, ranging from 0.55 (95% CI: 0.36, 0.70) for the Shannon index to 0.79 (95% CI: 0.69, 0.86) for Bray-Curtis. Overall, RNAlater, FOBT cards and Scope mouthwash were stable up to 4 days at room temperature. Samples collected using FOBT cards were generally comparable to RNAlater while the OMNIgene ORAL were less similar to Scope mouthwash. Conclusions: As microbiome measures for feces samples collected using RNAlater, FOBT cards and oral samples collected using Scope mouthwash were stable over four days at room temperature, these would be most appropriate for microbial analyses in these populations. However, one collection method should be consistently since each method may induce some differences. [ABSTRACT FROM AUTHOR]

In this study, fluorescence in situ hybridization (FISH) and PCR-amplified fragments of the 16SrDNA gene were used to determine prokaryotes diversity in Urmia Salt Lake. Prokaryote cell population in Urmia lake range from 3.1 ± 0.3 × 106, 2 ± 0.2 × 108, 4 ± 0.3 × 108, and 1.8 ± 0.2 × 108 cells ml−1 for water, soil, sediment, and salt samples by DAPI (4́, 6-diamidino-2-phenylindole) direct count, respectively. The proportion of bacteria and archaea in the samples determinable by FISH ranged between 36.1 and 55% and 48.5 and 55.5%, respectively. According to the DGGE method, some bands were selected and separated from the gel, then amplified and sequenced. The results of sequences were related to two phyla Proteobacteria (16.6%) and Bacteroidetes (83.3%), which belonged to four genera Salinibacter, Mangroviflexus, Pseudomonas, and Cesiribacter, and the archaeal sequences were related to Euryarchaeota phyla and three genera Halonotius, Haloquadratum, and Halorubrum. According to our results, it seems that prokaryotic populations in this hypersaline environment are more diverse than expected, and bacteria are so abundant and diverse and form the metabolically active part of the microbial population inhabiting this extreme environment. Molecular dependent and independent approaches revealed a different aspect of this environment microbiota. [ABSTRACT FROM AUTHOR]

The microbial population of soil is diverse and is regulated by different soil properties. This study aimed to determine the impact of climate and grazing on soil community composition in two semiarid areas, Kerman province, Iran. Soil samples were taken from four zones which were either cold or warm and either grazed by cattle or not grazed. Soil chemical analyses were determined by standard methods and the bacterial community by DNA extraction from soil followed by next generation sequencing of the 16S rRNA gene. Soil at cold areas had higher moisture, organic carbon, total nitrogen, available phosphorous and exchangeable potassium concentrations than warm sites. The abundance of Proteobacteria (28.3% ± 1.0) and Actinobacteria (44.6% ± 1.1) was highest at the cold-grazed and warm-grazed zones, respectively, which account for ~70% of all OTUs. Greater richness and evenness of bacteria at the cold areas, compared to the warm areas, was also observed and is attributed to more vegetation cover and soil organic matter, nutrient availability and moisture. There was no significant difference of chemical soil properties between the grazed and not grazed sites. However, significant differences were observed in bacterial diversity between the grazed and not grazed sites, suggesting that bacteria respond much more rapidly to grazing than to soil chemical properties. According to the Chao1 and J values, the least richness and the highest evenness belonged to the warm-grazed zone, indicating grazing had a greater effect at the warm areas, compared to the cold areas. In conclusion, change in community composition at managed (i.e. grazed versus not grazed) semiarid sites, estimated by next generation sequencing, precede detectable changes in soil chemical properties, thereby providing an early sign of change in soil quality. [ABSTRACT FROM AUTHOR]

Free-living amoebae belong to the genus Acanthamoeba; can feed on microbial population by phagocytosis, and with the capability to act as a reservoir and a vehicle of microorganisms to susceptible host. Therefore, the role of endosymbiosis in the pathogenesis of Acanthamoeba is complex and not fully understood. The aim of the present study was to identify bacterial, fungal, and human adenovirus (HADV) endosymbionts as well as evaluating the endosymbionts role of such organisms in the pathogenesis of Acanthamoeba in keratitis patients living in Iran. Fifteen Acanthamoeba (T4 genotype) isolates were recovered from corneal scrapes and contact lenses of patients with keratitis. Cloning and purification was performed for all isolate. Gram staining was performed to identify bacterial endosymbionts. DNA extraction, PCR, and nested PCR was set up to identify endosymbiont of amoeba. Evaluation of pathogenicity was conducted by osmo-tolerance and thermo-tolerance assays and cell culture, and then CPE (cytopathic effect) was survey. Statistical analysis was used between Acanthamoeba associated endosymbionts and Acanthamoeba without endosymbiont at 24, 48, 72, and 96 h. A p value < 0.05 was considered as significant, statistically. A total of 9 (60%) Acanthamoeba (T4 genotypes) isolates were successfully cloned for detecting microorganism endosymbionts. The only isolate negative for the presence of endosymbiont was ICS9. ICS7 (Pseudomonas aeruginosa , Aspergillus sp., and human adenovirus endosymbionts) and ICS2 (Escherichia coli endosymbiont) isolates were considered as Acanthamoeba associated endosymbionts. ICS7 and ICS2 isolates were highly pathogen whereas ICS9 isolate showed low pathogenicity in pathogenicity evaluated. Positive CPE for ICS7 and ICS2 isolates and negative CPE for ICS9 isolate were observed in cell culture. The average number of cells, trophozoites, and cysts among ICS7, ICS2, and ICS9 isolates at 24, 48, 72, and 96 h was significant. This is the first survey on microbial endosymbionts of Acanthamoeba in keratitis patients of Iran, and also the first report of Aspergillus sp, Achromobacter sp. , Microbacterium sp., Brevibacillus sp , Brevundimonas sp and Mastadenovirus sp in Acanthamoeba as endosymbionts. Our study demonstrated that microbial endosymbionts can affect the pathogenicity of Acanthamoeba ; however, further research is required to clarify the exact pattern of symbiosis, in order to modify treatment protocol. Image 1 • Our study demonstrated that microbial endosymbionts can affect the pathogenicity of Acanthamoeba. • This is the first report of some microbial endosymbionts in Acanthamoeba. • Further research is required to clarify the exact pattern of symbiosis, in order to modify treatment protocol. [ABSTRACT FROM AUTHOR]

The Anisian succession of Nakhlak (in Central Iran) is characterized by a siliciclastic succession with minor carbonate units, with massive carbonate mounds up to 50 m thick in its upper part. The mounds, constrained in age to the late Bithynian (Ismidicus Zone) by ammonoids and conodonts, are characterized by a flat top and a lateral pinch-out marked by clinostratified slopes (about 15° in dip). Stratigraphic and microfacies analyses document an inner part of the mound characterized by massive microbial carbonates with open-space structures (stromatactis) filled with fine-grained internal sediments and marine cements. Isolated sponges (up to 5 cm), serpulids and bryozoans are present, which grew on the calcimicrobial limestone. A narrow bioclastic margin (mainly with crinoids and brachiopods) produces most of the slope facies (consisting of bioclastic grainstone and packstone, with intraclasts from the inner part of the mounds) which interfinger basinward with volcaniclastic sandstones. The demise of carbonate productivity is marked on the top of the carbonate mounds by a condensed surface, rich in ammonoids, glaucony grains, and articulated crinoids, documenting a rapid drowning. Paleolatitude data support deposition in a tropical setting, and sedimentological constraints indicate deposition close to the fair-weather wave base, within the photic zone. The late Bithynian Nakhlak carbonate mounds developed before the appearance (documented since the Pelsonian in different parts of the world) of scleractinians which, despite the favorable environmental conditions, are absent at Nakhlak. The Nakhlak mounds thus represent one of the last occurrences of the microbial factories (which developed after the Permo-Triassic extinction event and persisted for most of the Middle Triassic, but with a gradually increasing role played by scleractinians) before the first appearance of the Mesozoic corals. [ABSTRACT FROM AUTHOR]

Introduction: Enterotoxigenic Escherichia coli (ETEC) causes diarrhoea by producing heat-labile (LT) or heat-stable (ST) enterotoxins after colonizing the small intestine by means of colonization factors (CFs). Although detection of the toxins is sufficient for verification of ETEC isolates, toxin-positive strains may be further analyzed for the presence of CFs. Antibiotics may shorten the duration of diarrhoea caused by ETEC, but the rapid emergence of resistant strains limits their usefulness. Methodology: ETEC isolates collected 10 years apart were compared for the prevalence of toxin types, CFs and antibiotic resistance. DNA/DNA hybridization with digoxigenin (DIG)-labeled probes was used for the detection of toxin types, and CF-typing was performed by DNA hybridization using DIG-labeled probes for cfaD and CS6 with slide agglutination. Disk diffusion was used to determine antibiotic resistance. The presence of class 1 integrons was detected by PCR. Results: ST-positive isolates were the most prevalent among the isolates from 1988, but a significant shift towards LT-gene carriage was observed in the 1998 group. CFA/I and CFA/IV were the most common CF types within both groups. The most prevalent resistance patterns among these isolates were ACSTSXT followed by ASTSXT and ASSXT. Conclusion: Our study of the two groups of isolates showed that the rate of LT and ST gene carriage, as well as antibiotic resistance markers, has changed in the ten years separating the two bacterial populations. These variations show the importance of monitoring pathogenic bacteria to obtain a near realistic picture of the circulating bacterial pathogens. [ABSTRACT FROM AUTHOR]

The type of vegetation cover affects the contents of organic matter and other soil features that can lead to variability of soil microbial processes, which play a key role in the nutrient cycle. This issue is especially important in mountainous semi-arid ecosystems, which have been introduced as fragile and vulnerable habitats. In the present study, labile contents of soil organic matter (SOM), microbial and enzymatic indices under the influence of forest and rangeland cover [i.e. natural forest with dominant species of Zelkova carpinifolia (Pall.) K. Koch. And three rangeland covers, converted form forest site almost 30 years ago, with dominant species of Festuca ovina L. Dactylis glomerata L. and Stachys byzantina K. Koch.] in Northern Iran have been considered including seasonal changes. The study aimed to investigate i) the effect of forest conversion to rangelands on SOM fractions, (ii) temporal dynamics of soil microbial processes and enzyme functions in different vegetation types, and (iii) determining the relationship between indices related to the content of organic matter and the size of microbial population in mountain ecosystems. Results showed that Zelkova tree type enhanced the levels of SOM contents, carbon and nutrient (nitrogen, phosphorous, potassium, calcium and magnesium) pools, and also with higher values in the summer season, the size of microbial population and processes. Additionally, the SOM turnover and microbial efficiency were almost suppressed in order to Zelkova > Festuca > Dactylis > Stachys vegetation types, respectively. Based on the obtained results, it can be concluded that the presence of tree cover in mountain ecosystems can strengthen soil function and create fertile islands. Therefore, the protection of natural forests is emphasized for the proper management and sustainability of habitats in semi-arid regions. [Display omitted] • Soil function was highly influenced by vegetation types (forest and rangelands). • Conversion of forest to rangelands suppressed labile organic matter fractions and nutrient pools. • Zelkova carpinifolia enhanced soil microbial processes especially in the summer season. • Presence of tree cover in mountain ecosystems might create fertile islands. [ABSTRACT FROM AUTHOR]