University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Identification of Pseudomonas Causing Leaf Spot and Bacterial Blight in Ornamental Plant Species of the Araceae Family in Iran Identification of Pseudomonas Causing Leaf Spot and Bacterial Blight in Ornamental Plant Species of the Araceae Family in Iran 1 16 29921 10.22108/bjm.2025.144982.1630 FA Parisa Emamy Department of Plant Protection, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Gholam Khodakaramian Department of Plant Protection, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Journal Article 2025 04 20 The cultivation of flowers and ornamental plants in greenhouses plays a significant role in the country’s economy through income generation and exportation. Bacterial pathogens, particularly leaf spot-causing species, can lead to severe damage, resulting in complete yield loss. Plants of the Araceae family are highly susceptible to these pathogens, yet research on this issue remains limited. Sampling was carried out on Araceae plants exhibiting leaf spot symptoms in various commercial greenhouses. Infected samples were cultured on nutrient agar medium, and 20 bacterial strains were isolated, purified, and preserved for pathogenicity and identification assays. Pathogenicity tests were performed on susceptible hosts, such as Epipremnum aureum (Pothos), Aglaonema treubii, and Syngonium podophyllum, which confirmed the virulence of selected strains. For identification, phenotypic characterizations such as fluorescent pigment production on King's B medium, LOPAT tests (Levan production, Oxidase activity, Potato soft rot, Arginine dihydrolase activity, and Tobacco hypersensitivity), carbon and energy utilization patterns, and sequencing of the 16S rRNA gene and housekeeping genes rpoD and recA were examined. Phenotypic and molecular data showed that the tested strains belonged to Pseudomonas aeruginosa. Based on the available literature, this is the first report of P. aeruginosa pathogenicity on plants from the Araceae family in Iran. The cultivation of flowers and ornamental plants in greenhouses plays a significant role in the country’s economy through income generation and exportation. Bacterial pathogens, particularly leaf spot-causing species, can lead to severe damage, resulting in complete yield loss. Plants of the Araceae family are highly susceptible to these pathogens, yet research on this issue remains limited. Sampling was carried out on Araceae plants exhibiting leaf spot symptoms in various commercial greenhouses. Infected samples were cultured on nutrient agar medium, and 20 bacterial strains were isolated, purified, and preserved for pathogenicity and identification assays. Pathogenicity tests were performed on susceptible hosts, such as Epipremnum aureum (Pothos), Aglaonema treubii, and Syngonium podophyllum, which confirmed the virulence of selected strains. For identification, phenotypic characterizations such as fluorescent pigment production on King's B medium, LOPAT tests (Levan production, Oxidase activity, Potato soft rot, Arginine dihydrolase activity, and Tobacco hypersensitivity), carbon and energy utilization patterns, and sequencing of the 16S rRNA gene and housekeeping genes rpoD and recA were examined. Phenotypic and molecular data showed that the tested strains belonged to Pseudomonas aeruginosa. Based on the available literature, this is the first report of P. aeruginosa pathogenicity on plants from the Araceae family in Iran.

https://bjm.ui.ac.ir/article_29921_6fea9e69885dfba459542ca93f213330.pdf

University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Study of the Microbial Population in the Anaerobic Digester of Isfahan's Municipal Solid Waste Using Next-Generation Sequencing Technique Study of the Microbial Population in the Anaerobic Digester of Isfahan's Municipal Solid Waste Using Next-Generation Sequencing Technique 17 32 30214 10.22108/bjm.2026.147268.1658 FA Meghdad Tahmasebi Isfahan Municipality Waste Management Organization, Iran Azam Aliasghari Veshareh Department of Microbiology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran Journal Article 2025 11 02 Anaerobic digestion is a microbial process that is widely used for the treatment of organic waste. Anaerobic digesters are considered an efficient method for waste management and renewable energy production. In this study, the communities of bacteria and archaea in the anaerobic digester of the Isfahan municipal solid waste treatment facility were investigated using the 16S rRNA gene next-generation sequencing technique. The main objective of this study was to identify and evaluate the most significant bacteria that play a key role in biogas production. The results of this study demonstrated that the microbial community in the anaerobic digester of the Isfahan region was mainly composed of two phyla: Bacteroidota (44.7%) and Firmicutes (30.5%), which together accounted for 75.2% of the total microbial population. Furthermore, the phyla Proteobacteria (9%), Cloacimonadota (5.6%), Patescibacteria (5.6%), and Actinobacteriota (4.5%) were present in significant proportions. At the genus level, uncharacterized genera, such as DMER64 and LNR_A2-18, were identified as dominant groups. In contrast, the presence of key functional genera, including syntrophic bacteria such as Syntrophomonas and Pelotomaculum, which play a crucial role in degrading long-chain fatty acids, along with hydrogenotrophic methanogens such as Methanobrevibacter, indicated the existence of an efficient metabolic network within this system. By identifying the microbial community and key functional groups, this study provides insights into the metabolic capacity of the digester. These findings can serve as a foundation for future studies investigating the direct relationship between these microbial communities and digester performance indicators, such as the methane production rate, and for proposing practical strategies for process optimization. Anaerobic digestion is a microbial process that is widely used for the treatment of organic waste. Anaerobic digesters are considered an efficient method for waste management and renewable energy production. In this study, the communities of bacteria and archaea in the anaerobic digester of the Isfahan municipal solid waste treatment facility were investigated using the 16S rRNA gene next-generation sequencing technique. The main objective of this study was to identify and evaluate the most significant bacteria that play a key role in biogas production. The results of this study demonstrated that the microbial community in the anaerobic digester of the Isfahan region was mainly composed of two phyla: Bacteroidota (44.7%) and Firmicutes (30.5%), which together accounted for 75.2% of the total microbial population. Furthermore, the phyla Proteobacteria (9%), Cloacimonadota (5.6%), Patescibacteria (5.6%), and Actinobacteriota (4.5%) were present in significant proportions. At the genus level, uncharacterized genera, such as DMER64 and LNR_A2-18, were identified as dominant groups. In contrast, the presence of key functional genera, including syntrophic bacteria such as Syntrophomonas and Pelotomaculum, which play a crucial role in degrading long-chain fatty acids, along with hydrogenotrophic methanogens such as Methanobrevibacter, indicated the existence of an efficient metabolic network within this system. By identifying the microbial community and key functional groups, this study provides insights into the metabolic capacity of the digester. These findings can serve as a foundation for future studies investigating the direct relationship between these microbial communities and digester performance indicators, such as the methane production rate, and for proposing practical strategies for process optimization.

https://bjm.ui.ac.ir/article_30214_edf0562b5381e5507d2c12a469112eb1.pdf

University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Computational Evaluation of Diagnostic Epitopes for the Detection of Mycoplasma Infection in Small Ruminants Computational Evaluation of Diagnostic Epitopes for the Detection of Mycoplasma Infection in Small Ruminants 33 44 30316 10.22108/bjm.2026.148014.1664 FA Malihe Akbarzadeh Niaki Department of Microbial Biotechnology, Faculty of Biotechnology, Amol University of Special Modern Technologies Journal Article 2026 01 01 Mycoplasma agalactiae is the primary etiological agent of contagious agalactia in small ruminants, a disease that has been reported in several countries, including Iran. The microorganism's ability to persist in chronic infections within herds results in substantial economic losses in the dairy industry. Recent advances in bioinformatics tools for macromolecular analysis, combined with the availability of the complete genome sequence of M. agalactiae, have enabled the systematic evaluation of diagnostically relevant epitopes and the rational design of novel constructs for diagnostic applications. The objective of the present study was to identify and evaluate epitopes with diagnostic potential and to design a multi-epitope protein suitable for use in diagnostic assays. The open reading frames (ORFs) of M. agalactiae were extracted using bioinformatics approaches. These ORFs were subsequently screened based on cellular localization, species specificity, toxicity, allergenicity, immunogenicity, and membrane-associated features to select appropriate candidate proteins for B-cell epitope prediction. The most promising epitopes were then employed in the design of a diagnostic multi-epitope protein. In silico analyses were performed to evaluate its structural and physicochemical properties, solubility, and interaction with the host MHC class II receptor. The results demonstrated that the bioinformatics screening process led to the selection of 5 ORFs and, ultimately, 7 B-cell epitopes exhibiting high immunogenicity, non-toxic and non-allergenic, and suitable specificity for M. agalactiae. Furthermore, the designed multi-epitope protein exhibited favorable structural stability, adequate solubility, and strong predicted interactions with the MHC class II receptor of goat immune cells. Overall, these findings suggest that the epitopes have significant potential for use in diagnostic assays and represent promising candidates for subsequent experimental validation of M. agalactiae infection. Mycoplasma agalactiae is the primary etiological agent of contagious agalactia in small ruminants, a disease that has been reported in several countries, including Iran. The microorganism's ability to persist in chronic infections within herds results in substantial economic losses in the dairy industry. Recent advances in bioinformatics tools for macromolecular analysis, combined with the availability of the complete genome sequence of M. agalactiae, have enabled the systematic evaluation of diagnostically relevant epitopes and the rational design of novel constructs for diagnostic applications. The objective of the present study was to identify and evaluate epitopes with diagnostic potential and to design a multi-epitope protein suitable for use in diagnostic assays. The open reading frames (ORFs) of M. agalactiae were extracted using bioinformatics approaches. These ORFs were subsequently screened based on cellular localization, species specificity, toxicity, allergenicity, immunogenicity, and membrane-associated features to select appropriate candidate proteins for B-cell epitope prediction. The most promising epitopes were then employed in the design of a diagnostic multi-epitope protein. In silico analyses were performed to evaluate its structural and physicochemical properties, solubility, and interaction with the host MHC class II receptor. The results demonstrated that the bioinformatics screening process led to the selection of 5 ORFs and, ultimately, 7 B-cell epitopes exhibiting high immunogenicity, non-toxic and non-allergenic, and suitable specificity for M. agalactiae. Furthermore, the designed multi-epitope protein exhibited favorable structural stability, adequate solubility, and strong predicted interactions with the MHC class II receptor of goat immune cells. Overall, these findings suggest that the epitopes have significant potential for use in diagnostic assays and represent promising candidates for subsequent experimental validation of M. agalactiae infection.

https://bjm.ui.ac.ir/article_30316_b4830cc56a980b6dd754e0df5d2801cb.pdf

University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Investigation of Antibiotic Resistance Patterns and Prevalence of Resistance Genes in Clinical Isolates of Acinetobacter baumannii in a teaching hospital in Tehran Investigation of Antibiotic Resistance Patterns and Prevalence of Resistance Genes in Clinical Isolates of Acinetobacter baumannii in a teaching hospital in Tehran 45 58 30373 10.22108/bjm.2026.148403.1669 FA Mahboobeh Nazarpoor Department of Microbiology, Faculty of Advanced Science and Technology, TMS.C., Islamic Azad University, Tehran, Iran. Seyyed Khalil Shokouhi Mostafavi Department of Microbiology, Faculty of Medicine, TMS.C., Islamic Azad University, Tehran, Iran. Amir Hossein Massoud Department of Immunology, Faculty of Medicine, TMS.C., Islamic Azad University, Tehran, Iran. Fatemeh Faraji Immunology Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran. Sara Minaeian Antimicrobial Resistance Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran Journal Article 2026 02 16 Introduction: At present, antibiotic resistance is recognized as one of the major global threats to human health. The clinical importance of Acinetobacter baumannii is due to its ability to acquire and transmit antibiotic resistance factors. Resistance genes, such as class D β-lactamases (oxacillinases), enable A. baumannii to resist the effects of several antibiotic families. The aim of this study was to investigate the antibiotic resistance pattern and estimate the prevalence of the resistance genes blaOXA-23 and blaOXA-51 in A. baumannii isolates obtained from hospitalized patients in a hospital in Tehran Province. Materials and Methods: In this study, 60 A. baumannii isolates were collected from hospitalized patients in a teaching hospital in Tehran Province in 2024. Following biochemical tests for final bacterial identification, the antibiotic susceptibility of isolates against 12 antibiotics was determined using the agar disk diffusion method. Colistin susceptibility was also evaluated using the disk diffusion method. Then, the prevalence of antibiotic resistance genes blaOXA-23 and blaOXA-51 was assessed by PCR. Results: In this study, among 60 isolates, the highest observed susceptibility was to colistin with 3.3% resistance, while the highest resistance (100%) was to imipenem, cefepime, cefotaxime, piperacillin–tazobactam, and ciprofloxacin. The prevalence of blaOXA-23 and blaOXA-51 was 81.6% and 100%, respectively. Conclusion: The increase in antibiotic resistance and widespread prevalence of resistance genes have caused serious concerns. Effective infection control and prevention of the spread of drug-resistant bacteria require precise drug prescription management and timely identification of resistant isolates. Introduction: At present, antibiotic resistance is recognized as one of the major global threats to human health. The clinical importance of Acinetobacter baumannii is due to its ability to acquire and transmit antibiotic resistance factors. Resistance genes, such as class D β-lactamases (oxacillinases), enable A. baumannii to resist the effects of several antibiotic families. The aim of this study was to investigate the antibiotic resistance pattern and estimate the prevalence of the resistance genes blaOXA-23 and blaOXA-51 in A. baumannii isolates obtained from hospitalized patients in a hospital in Tehran Province. Materials and Methods: In this study, 60 A. baumannii isolates were collected from hospitalized patients in a teaching hospital in Tehran Province in 2024. Following biochemical tests for final bacterial identification, the antibiotic susceptibility of isolates against 12 antibiotics was determined using the agar disk diffusion method. Colistin susceptibility was also evaluated using the disk diffusion method. Then, the prevalence of antibiotic resistance genes blaOXA-23 and blaOXA-51 was assessed by PCR. Results: In this study, among 60 isolates, the highest observed susceptibility was to colistin with 3.3% resistance, while the highest resistance (100%) was to imipenem, cefepime, cefotaxime, piperacillin–tazobactam, and ciprofloxacin. The prevalence of blaOXA-23 and blaOXA-51 was 81.6% and 100%, respectively. Conclusion: The increase in antibiotic resistance and widespread prevalence of resistance genes have caused serious concerns. Effective infection control and prevention of the spread of drug-resistant bacteria require precise drug prescription management and timely identification of resistant isolates.

https://bjm.ui.ac.ir/article_30373_fce4d3985f768cbe70b54c5b2efe65a2.pdf

University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Synthesis and characterization of nano-liposomes loaded with clove essential oil and investigation of their antibacterial and antifungal effects Synthesis and characterization of nano-liposomes loaded with clove essential oil and investigation of their antibacterial and antifungal effects 59 72 30361 10.22108/bjm.2026.148096.1665 FA Armita Aryan Manesh Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran Abolghasem Abbasi Kajani Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran Journal Article 2026 01 12 Nowadays, the development of new antimicrobial agents to replace antibiotics, especially biological compounds, is of great interest. In this study, the synthesis of nanoliposomes loaded with clove essential oil and their use as antibacterial and antifungal agent were investigated. For this purpose, liposomes were synthesized using the ethanol injection method with lecithin as a precursor in the presence of clove essential oil. Their physicochemical properties were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and zetasizer analysis. Then, their antimicrobial effects were evaluated against Escherichia coli and Staphylococcus aureus bacteria, as well as Aspergillus niger, Aspergillus terreus and Aspergillus flavus fungi. Nanoliposomes loaded with clove essential oil showed high colloidal stability, with a zeta potential of -58.5 and no sedimentation was observed even after 6 months. TEM imaging showed that the nanoparticles had a hemispherical and homogeneous shape with a size range of 100-200 nm. Nanoliposomes showed high biocompatibility, with 73.8% and 81.3% of human fibroblast cells remaining viable after incubation with 200 μg/mL of the initial and clove essential oil-loaded nanoliposomes, respectively. Although nanoliposomes loaded with clove essential oil showed limited antibacterial effect against S. aureus and E. coli strains, they showed a potent antifungal effect on A. niger, A. terreus and A. flavus, with complete growth inhibition of fungal mycelia at concentrations of 2, 2, and 1 mg/mL, respectively. Based on the results, clove essential oil-loaded nanoliposomes can be a suitable antifungal agent for food and pharmaceutical applications. Nowadays, the development of new antimicrobial agents to replace antibiotics, especially biological compounds, is of great interest. In this study, the synthesis of nanoliposomes loaded with clove essential oil and their use as antibacterial and antifungal agent were investigated. For this purpose, liposomes were synthesized using the ethanol injection method with lecithin as a precursor in the presence of clove essential oil. Their physicochemical properties were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and zetasizer analysis. Then, their antimicrobial effects were evaluated against Escherichia coli and Staphylococcus aureus bacteria, as well as Aspergillus niger, Aspergillus terreus and Aspergillus flavus fungi. Nanoliposomes loaded with clove essential oil showed high colloidal stability, with a zeta potential of -58.5 and no sedimentation was observed even after 6 months. TEM imaging showed that the nanoparticles had a hemispherical and homogeneous shape with a size range of 100-200 nm. Nanoliposomes showed high biocompatibility, with 73.8% and 81.3% of human fibroblast cells remaining viable after incubation with 200 μg/mL of the initial and clove essential oil-loaded nanoliposomes, respectively. Although nanoliposomes loaded with clove essential oil showed limited antibacterial effect against S. aureus and E. coli strains, they showed a potent antifungal effect on A. niger, A. terreus and A. flavus, with complete growth inhibition of fungal mycelia at concentrations of 2, 2, and 1 mg/mL, respectively. Based on the results, clove essential oil-loaded nanoliposomes can be a suitable antifungal agent for food and pharmaceutical applications.

https://bjm.ui.ac.ir/article_30361_24dff3f26318c2a326e4905ca6d1a41c.pdf

University of Isfahan Journal of Microbial Biology 3060-7647 15 57 2026 03 21 Investigation of the antifungal activity of biosynthesized silver nanoparticles and lavender essential oil against biodeteriorative fungi isolated from the Masjed-e Jāmé of Isfahan Investigation of the antifungal activity of biosynthesized silver nanoparticles and lavender essential oil against biodeteriorative fungi isolated from the Masjed-e Jāmé of Isfahan 73 87 30438 10.22108/bjm.2026.148351.1668 FA Azam Aliasghari Veshareh Department of Microbiology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran Parisa Mohammadi Department of Microbiology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran Parinaz Ghadam Department of Biotechnology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran Journal Article 2026 02 15 Biodeterioration is irreversible damage caused by microorganisms or their metabolites to historical monuments, and fungi are considered important factors in this deterioration. In this regard, the use of new, effective, and low-risk antifungal agents, such as biosynthesized nanoparticles and plant essential oils, is of interest. The aim of this study was to investigate and compare the antifungal activity of silver nanoparticles synthesized using an aqueous extract of green walnut shells and lavender essential oil against six species of biodeteriorative fungi isolated from Iran cultural heritage. The antifungal activity was evaluated using two methods: diffusion in agar and determination of minimum inhibitory concentration and minimum lethal concentration. The results showed that silver nanoparticles at a concentration of 1 mg/mL were effective against a wide range of fungi, whereas lavender essential oil had favorable activity at high concentrations (50 and 100%). Based on the microtiter plate method, nanoparticles with MIC values between 0.125 and 1 mg/mL and strong bactericidal properties against fungi such as Aspergillus niger, Aspergillus flavus, and Penicillium polonicum showed their superiority. In contrast, the essential oil exhibited no measurable fungicidal properties against the three fungi. According to the results, the biosynthesized silver nanoparticles are very efficient and promising option, and lavender essential oil can be considered an alternative or complementary natural agent for controlling the biodeterioration of cultural heritage, depending on the conservation conditions and the concentration used. Furthermore, determining the final decision for the application of these compounds requires additional studies on the materials used in historical monuments. Biodeterioration is irreversible damage caused by microorganisms or their metabolites to historical monuments, and fungi are considered important factors in this deterioration. In this regard, the use of new, effective, and low-risk antifungal agents, such as biosynthesized nanoparticles and plant essential oils, is of interest. The aim of this study was to investigate and compare the antifungal activity of silver nanoparticles synthesized using an aqueous extract of green walnut shells and lavender essential oil against six species of biodeteriorative fungi isolated from Iran cultural heritage. The antifungal activity was evaluated using two methods: diffusion in agar and determination of minimum inhibitory concentration and minimum lethal concentration. The results showed that silver nanoparticles at a concentration of 1 mg/mL were effective against a wide range of fungi, whereas lavender essential oil had favorable activity at high concentrations (50 and 100%). Based on the microtiter plate method, nanoparticles with MIC values between 0.125 and 1 mg/mL and strong bactericidal properties against fungi such as Aspergillus niger, Aspergillus flavus, and Penicillium polonicum showed their superiority. In contrast, the essential oil exhibited no measurable fungicidal properties against the three fungi. According to the results, the biosynthesized silver nanoparticles are very efficient and promising option, and lavender essential oil can be considered an alternative or complementary natural agent for controlling the biodeterioration of cultural heritage, depending on the conservation conditions and the concentration used. Furthermore, determining the final decision for the application of these compounds requires additional studies on the materials used in historical monuments.

https://bjm.ui.ac.ir/article_30438_71ae45d2e9b7ef754a6194ffe904a2c4.pdf