Khosrow Chehri | Razi University of Kermanshah, Iran (original) (raw)

Papers by Khosrow Chehri

Case Studies in Construction Materials, Dec 1, 2022

Agricultural research & technology, Apr 26, 2017

One of the serious problems in the agriculture industry is contamination of agricultural plants a... more One of the serious problems in the agriculture industry is contamination of agricultural plants and their products with fungi. Fusarium spp. Are known as very important fungi that not only invade agricultural plants in both pre-and post-harvesting steps, but also disperse through the world. There are different methods to control disease caused by Fusarium spp., but they are associated with some limitations. Among these methods, bio control takes considerable attentions of researchers. Here, we briefly consider problems caused by Fusarium in agriculture industry and take a short look on methods to manage the fungi.

DOAJ (DOAJ: Directory of Open Access Journals), Aug 1, 2015

Fifty Fusarium isolates were obtained from 20 garden soil samples in Hormozgan province (S Iran).... more Fifty Fusarium isolates were obtained from 20 garden soil samples in Hormozgan province (S Iran). The isolates were identified based on morphological and molecular data. Sequence data were generated for TEF-1α gene, following PCR amplification. Among the identified species, Fusarium mangiferae, F. gaditjirrii, and F. decemcellulare represent new records to the mycobiota of Iran.

Avicenna Journal of Clinical Microbiology and Infection, Dec 29, 2021

Background The urinary system is one of the major vital systems in the human body, which is respo... more Background The urinary system is one of the major vital systems in the human body, which is responsible for purifying the blood from toxic materials and returning clean blood to the circulatory system. This system, referred to as the renal system, includes the bladder, ureters, kidneys, and urethra. Microorganisms cause many infectious diseases for the human body, especially for the urinary tract system; therefore, it is essential to eliminate and control them. The emergence of antibiotic-resistant microorganisms has been increased recently, and this increase necessitates finding alternative agents to eliminate these microbes (1). Today, biofilms have become a major medical problem due to their high resistance to the immune system, as well as their resistance to antimicrobial medicine and other disinfectants (2). There are different microorganisms capable of forming a biofilm on different surfaces which can accumulate on medical devices and cause specific problems in treatment by colonization and infection (3). Most of the gram-positive bacteria, gram-negative bacteria, and yeast in nature make up the biofilm. Biofilms can cause many hospitalized infections, indicating their important role in developing infectious diseases (4). Several strains of microbial pathogens can grow in biofilm structures. These structures can be developed by one species of microbe or a mixture of several microorganisms. Biofilms are the source of many resistant systemic infections such as urinary tract, ear, tooth, catheter, and other infections (5). Therefore, identifying factors that can inhibit the formation of biofilms has recently received extensive attention from scientists (6), including nanoparticles (NPs). The microorganisms have a high potential for adapting to new environments and antibiotics. The development in nanotechnology has provided a competitive condition against the adaptability characteristics of microorganisms and limited their growth in new media and, consequently, prevented their infections (7). The application of some nano-sized materials has shown that they have a significant effect on microbe cells (8). Many nanomaterials, such as zinc, silver, and, Copper have been used to eliminate microorganisms. Haghi et al used titanium dioxide (TiO 2) NPs in dental manufacturing and showed that this NP had highly effective properties against yeast and bacteria causing teeth calcification (9). TiO 2 has received special attention in these studies for its high photocatalytic properties (10). Some of the NPs' features that make them superior to other NPs include

Bioimpacts, Oct 25, 2021

Introduction: Aerobic vaginitis (AV) is a type of vaginal infection that occurs at the reproducti... more Introduction: Aerobic vaginitis (AV) is a type of vaginal infection that occurs at the reproductive age of women. In this study, we aimed to study the possible anti-AV therapeutic effects of silver nanoparticles (AgNPs) and L-carnitine (LC) in the mouse model. Methods: AV model was established by intra-vaginal inoculation of 108 CFU/mL Staphylococcus aureus and Escherichia coli (1:1) in adult NMRI mice. Susceptibilities of the bacteria were examined against AgNPs by inhibitory concentration (IC-50 and IC-90) and minimum biofilm inhibitory concentration (MBIC- 90) methods. The regimens therapy was intra-vaginal inoculation of AgNPs at MBIC- 90 and a daily injection of 250 mg/kg LC for two weeks. Mice were classified into healthy (control) and AV groups and then treated by LC, AgNPs, and AgNPs + LC. The vaginal smears were taken daily and tissue sections were prepared using the hematoxylin and eosin (H & E) method. Results: Minimum inhibitory concentrations (MICs) of AgNPs for E. coli, S. aureus, and their mixture were 250, 125, and 500 ppm, and their MBIC-90% were 500, 250, and 1000 ppm, respectively. The estrus cycle of mice treated with co-administration of AgNPs and LC was similar to the control group (P < 0.05). The results of histology also showed that infected mice were treated with AgNPs and LC, simultaneously. Conclusion: Single bacteria are more sensitive than their mixed model to these NPs. Co-administration of AgNPs as an antibacterial agent and LC as an antioxidant agent can treat AV in the infected mice.

Journal of Plant Protection Research

Fusarium wilt is one of the most severe diseases of chickpea in the major growing areas of chickp... more Fusarium wilt is one of the most severe diseases of chickpea in the major growing areas of chickpea production in western Iran. To identify Fusarium spp. associated with chickpea plants showing symptoms of yellowing and wilting, 58 chickpea fields were sampled and 106 Fusarium spp. isolates were obtained from six different regions of Kermanshah Province in western Iran during 2018 and 2019 crop seasons. Thirty-six isolates obtained from stem or lower stem tissues were selected for pathogenicity, morphological and molecular identification using polymease chain reaction species-specific primers. Eleven isolates of Fusarium spp. were selected for sequence analyzing the translation elongation factor 1-α (EF-1α), and β-tubulin gene regions. Phylogenetic analysis of concatenated DNA sequences of both gene regions of these isolates plus other taxa revealed that 11 Fusarium spp. isolates were clustered into five distinct groups. Based on the results of morphological and molecular identification five Fusarium species were identified. Pathogenicity tests showed that F. oxysporum f. sp. ciceris and F. redolens isolates had the highest disease incidence on JG-62 and Bivenij cvs. and F. hostae, F. equiseti and F. acuminatum isolates had the lowest disease incidence. No sign of vascular discoloration was observed in longitudinal or transverse sections of chickpea plants affected by F. redolens isolates. Instead, brown to black necrosis was observed on the surface of tap-roots and crowns. No correlation was found between geographical distribution and pathogenicity of isolates. This is the first report of morphological, molecular and pathogenicity characteristics of F. redolens and F. hostae isolated from chickpea stems or lower stems in Iran.

BioImpacts

Case Studies in Construction Materials

African Journal of Microbiology Research, Jun 18, 2010

Cucurbits (Cucurbitaceae) are among the important plant families providing edible products to hum... more Cucurbits (Cucurbitaceae) are among the important plant families providing edible products to humans worldwide. It is known fact that various pathogenic fungi can attack the plants and cause diseases and resultantly yield losses. The aim of this study was to isolate and identify the plant pathogenic fungi from cucurbit plants and to evaluate their pathogenicity on cucurbits. A total of 101 cucurbit samples infected with diseases were collected from different places in Kermanshah Province, Iran. From these samples 101 strains of various pathogenic fungi were isolated and identified through morphological characters. All strains were belongs to Fusarium oxysporum , Macrophomina phaseolina, Phytophthora melonis, Phytophthora drechsleri, Pythium aphanidermatum and two morphotypes of Fusarium solani species complex (FSSC). P. aphanidermatum and Phytophthora sp. strains were recovered from the samples collected from irrigated field, while Fusarium and M. phaseolina strains from rain fed field. All these pathogenic fungi were evaluated to study their pathogenicity on cucumber (Cucumis sativum) and honeydew melon (Cucumis melo). P. melonis, P. drechsleri, F. oxysporum and P. aphanidermatum caused the damping off within 10-20 days on both plants tested. The stem rot symptoms were observed on the 7th day after inoculation of F. solani and M. phaseolina on both plants tested. The inoculated fungi were re-isolated from the diseased plants to prove the Koch's postulates. This is the first comprehensive report on identity and distribution of major plant pathogenic fungi causing root and stem rots on cucurbits in west of Iran.

African Journal of Agricultural Research, Aug 18, 2011

Dry rot of potato caused by Fusarium species is a common and commercially important disease of po... more Dry rot of potato caused by Fusarium species is a common and commercially important disease of potato tubers found in all production areas of the world, including Malaysia. The objective of this study was to identify Fusarium species associated with wet market potatoes and their pathogenicity on potato tubers in Malaysia. In this survey, 65 Fusarium strains were isolated and identified from diseases decayed potato's segments collected from different regions in Malaysia. All of these 65 isolates, which belong to two morphotypes of Fusarium solani species complex (FSSC) and Fusarium oxysporum, were evaluated to study their pathogenicity on healthy potato tubers. The tubers rot symptoms were observed on the 21st day after inoculation of F. solani and F. oxysporum strains on the tubers tested. In the tubers inoculation tests, lesion sizes were quite variable; therefore, the measurement was done to compare the depth and width of lesion expansion among the strains. The results of the pathogenicity test revealed that F. solani isolates FSO4, FSO12 (morphotype I), FSO18 (morphotype II) and F. oxysporum isolates FOX4 and FOX16 were strongly pathogenic to inoculated potato tubers. The inoculated fungi were re-isolated from the diseased potato tubers to prove the Koch's postulates. The present study showed that two morphotypes of F. solani were associated with tuber rot of potato in Malaysia. This is the first comprehensive report on identity and distribution of major pathogenic fungi causing potato dry rot in Malaysia.

Biological Journal of Microorganism, 2017

Introduction: The present study was carried out to evaluate the occurrence of toxicogenic Fusariu... more Introduction: The present study was carried out to evaluate the occurrence of toxicogenic Fusarium proliferatumstrains isolated from nuts in Iraq. Materials and methods: A total of 108 nut samples collected from different markets in Iraq. Strains of Fusarium spp. isolated from nuts seeds and their morphological characterization of the strains were examined based on their growth on carnation leaf agar (CLA) and potato dextrose agar (PDA). The identification of F. proliferatum isolates were confirmed molecularly using species specific primers of PRO1/PRO2 primers. PCR-based detection of fumonisin-synthesis-pathway gene was also used to determine the potential of F. proliferatum isolates to produce fumonisin using FUM1 gene-based (FUM1 F/FUM1 R) primers. Results: Based on morphological features 28 fungal isolates were obtained from nuts and identified into four species F. proliferatum (12), Aspergillus niger (8), Aspergillus flavus (5), and Penicillium sp. (3). The primers PRO1/PRO2 pr...

Avicenna Journal of Clinical Microbiology and Infection, 2021

Background: T Microorganisms cause many diseases for the human body such as urinary tract infecti... more Background: T Microorganisms cause many diseases for the human body such as urinary tract infection and, therefore, it is highly important to eliminate and control them. Bacterial resistance to different types of antibiotics was increased and it is necessary to find alternative agents to eliminate these microbes. Methods: This study aimed was to evaluate the antimicrobial effect of different concentrations of titanium dioxide nanoparticles (TiO2 NPs) on some gram-positive bactria, gram-negative bacteria, and Candida albicans. TiO2 NPs were synthesized using the chemical methods, coated with carboxymethyl cellulose (CMC) and prepared in different concentrations (0.098, 0.196, 0.392, 0.784, 1.568, and 3.136 mg/mL). Eventually, a minimum inhibitory concentration (MIC) and a minimum biofilm inhibitory concentration (MBIC) were applied to investigate the effect of TiO2 NPs on microorganisms. Results: According to the study results, the MICs of TiO2 NPs were found to be 1.489, 1.208, and ...

(FSSC) have been known as plant, animal, and human path-ogens. Nevertheless, the taxonomic status... more (FSSC) have been known as plant, animal, and human path-ogens. Nevertheless, the taxonomic status of such an impor-tant group of fungi is still very confusing and many new species as well as lineages have been elucidated recently. Unfortunately, most of the new taxa came from temperate and subtropical regions. Therefore, the objectives of the pres-ent study were to identify strains of FSSC recovered from different sources in Malaysia. In the present study, 55 strains belonging to the FSSC were examined and phylogenetically analyzed on the basis of internal transcribed spacer (ITS) regions and partial translation elongation factor-1 (TEF-1α) sequences. Based on morphological features, a total of 55 strains were selected for molecular studies. Based on morpho-logical features, the strains were classified into four described Fusarium species, namely Fusarium keratoplasticum, Fusarium falciforme, FSSC 5, and Fusarium cf. ensiforme, and one unknown phylogenetic species was introduced. Although the data obtained from morphological and molecu-lar studies sufficiently supported each other, the phylogenetic trees based on ITS and TEF-1α dataset clearly distinguished closely related species and distinctly separated all morpholog-ical taxa. All members of FSSC in this research were reported for the first time for Malaysian mycoflora.

Journal of Environmental Chemical Engineering, 2021

Abstract The aim of this research is to confect Chloroxine-conjugated AgNPs (COX-AgNPs), employin... more Abstract The aim of this research is to confect Chloroxine-conjugated AgNPs (COX-AgNPs), employing an eco-friendly method. The conjugation of antibiotics and antibacterial drugs with nanoparticles demonstrates better biological activity compared to free antibacterial and antibiotic molecules. Therefore, our groups employed Echinophora platyloba DC extract to prepared silver nanoparticles and subsequent conjugation of them to antibacterial drug Chloroxine. We employed the analytical techniques (UV–vis, DLS, zeta potential, SEM-EDX, FT-IR, XRD, and TEM) to investigate the composition, morphology, and size of the green synthesized AgNPs and COX-AgNPs. Our synthesized AgNPs displayed a remarkable antibacterial and antifungal activity against various microorganisms. The green synthesized AgNPs reported in this work is relatively smaller than some green synthesized AgNPs reported in the literature. Moreover, the efficacy of AgNPs was elevated by conjugating the antibacterial drug Chloroxine to them. Also, our finding indicated that COX-AgNPs have potential to accelerate wound healing, which refers to the antibacterial and antifungal activity of COX-AgNPs.

International Journal of Molecular and Clinical Microbiology, 2020

Stored nuts in the markets are naturally infected by different fungal species such as Aspergillus... more Stored nuts in the markets are naturally infected by different fungal species such as Aspergillus. The present study was carried out to evaluate the occurrence of toxicogenic A. flavus strains on nuts in Iraq. A total of 112 nuts samples including hazelnuts, pistachio, peanut, and walnut with typical symptoms of dark and green discolored lesions on kernels were collected from various markets in Baghdad. Strains of Aspergillus spp. isolated from nuts seeds and their morphological characterization was based on MEA, PDA, and CYA. The identification of A. flavus isolates were confirmed molecularly using primers T1/T2. A total of 25 fungal isolates belonged to Aspergillus species that were identified as A. niger (10), A. flavus (10), and A. japonicus (5). In molecular analysis, sequences of partial β-tubulin gene were blasted in GenBank to confirm morphological identification of A. flavus isolates. Aflatoxins (AFs) contamination of ten infected samples with A. flavus was evaluated using ...

Maize (Zea mays L.) is one of the most important primary food crops and is grown in all the conti... more Maize (Zea mays L.) is one of the most important primary food crops and is grown in all the continents of the world. Mycotoxin contamination of stored corn grains has long been a major problem in different regions of Iran, which mostly are produced by toxigenic fungal species. Aspergillus species are major causes of preand post-harvest degradation of corn grains. This study was aimed to identify morphologically Aspergillus species isolated from stored corn grains in Kermanshah province during 2006-2013 growing seasons. One-hundred samples, mostly from diseased corn grains for human and animal consumptions were collected from different geographic regions of the province. One-hundred Aspergillus isolates were collected and identified into six species i.e. A. niger (40%) followed by A. flavus (27%), A. ochraceus (15%), A. fumigatus (10%), A. japonicus (5%) and A. sclerotiorum (3%). We also determined the Aflatoxin B (AFB ) contamination 1 1 status in the samples by enzyme-linked immune...

In order to determine the fumonisin producingisolates of the Fusarium fujikuroi species complex (... more In order to determine the fumonisin producingisolates of the Fusarium fujikuroi species complex (FFSC), associated with infected spikes, and ear rot of grass plants, we examined 78 samples collected from Kermanshah province, Iran. Based on morphological characters, twenty two isolates assigned to the FFSC and were identified as F. proliferatum (ten isolates), F. verticillioides (seven isolates), and F. subglutinans (five isolates). This was additionally approved using the specific primers of F. verticillioides, F. proliferatum, and F. subglutinans, i.e. VER1/VER2, PRO1/PRO2, and SUB1/SUB2, respectively. PCR-based detection of the fumonisin-producing isolates of FFSC was also achieved using the primers FUM1 F/FUM1 R. Out of twenty two isolates, eleven isolates (50%) determined as fumonisin chemotype.

Fusarium species are cosmopolitan species that frequently isolated from soils and plantdebris and... more Fusarium species are cosmopolitan species that frequently isolated from soils and plantdebris and can seriously damaged plant, animal and human. Persian Gulf beaches in Iranare the ideal habitat for a variety of Fusarium species. Therefore, the study is conductedto gather some information on the population of Fusarium species which could be foundin Persian Gulf beaches in Iran. The study involved the isolation and identification ofFusarium species from beach soil samples in Persian Gulf beaches. The direct isolationtechnique from soil particles was used to isolate Fusarium species from beach soilsamples. Fusarium species were identified by the observation of macroscopic andmicroscopic characteristics. Fusarium solani is the most common species found on thebeach samples which had the highest percentage of abundance (58%). The percentage ofabundance for other Fusarium species is relatively low, where F. proliferatum consists of12%, followed by F. equiseti (10%), F. falciforme (10%), F...

The objects of this study concerted to identify the develop Aspergillus flavus, Hymenocrater long... more The objects of this study concerted to identify the develop Aspergillus flavus, Hymenocrater longiflovus extracts have been evaluated for their bioactivities on A. flavus. In total, 100 samples of nuts were collected from markets of Iraq. Through the study, PDA media were used to isolate A. flavus. The results revealed the A. flavus was identified in 65% from nuts. Aspergillus flavus isolates were further culture on PDA media contain ethanol H. longiflovus extracts, and hydroethanol H. longiflovus extracts. The results showed the effect of different concentrations of plant extracts on radial mycelial growth of A. flavus. Increasing concentration of plant extract significantly reduced the mycelial growth of the pathogen. These results evidently indicate that the plant H. longiflovus had inhibitory effect on post-harvest pathogen of nuts in alcoholic extracts of H. longiflovus have been reported to have antimicrobial properties.

To identify fumonisin chemotype of Gibberella fujikuroi species complex (GFSC) isolated from bare... more To identify fumonisin chemotype of Gibberella fujikuroi species complex (GFSC) isolated from barely, 75 barely samples were collected from different markets in Western Iran. Based on morphological characters, 40 Fusarium isolates were obtained from the grains and grouped into four species F. proliferatum (14) and F. subglutinans (3) as the two known GFSC members, F. graminearum senso lato (13), and F. equiseti (10). The identification of F. proliferatum and F. subglutinans isolates were confirmed molecularly using species-specific of PRO1/PRO2 and SUB1/SUB2 primers, respectively, which selectively amplified the partial calmodulin gene of rDNA. PCRbased detection of a mycotoxin-synthesis-pathway gene was also used to determine the potential of the analyzed strains to produce fumonisin using FUM1 F/FUM1 R primers. Of 17 tested isolates, 8 isolates (47%) are fumonisin chemotype. To the best of our knowledge, this is the first report on molecular identification and mycotoxigenic capacit...