International Journal of Microbiology
 Journal metrics
See full report
Acceptance rate15%
Submission to final decision74 days
Acceptance to publication16 days
CiteScore3.000
Journal Citation Indicator0.610
Impact Factor-

Indexing news

International Journal of Microbiology has been accepted into Food Science & Technology Abstracts.

Go to Table of Contents

 Journal profile

International Journal of Microbiology publishes papers on microorganisms and their interaction with hosts and the environment. The journal covers all microbes, including bacteria, fungi, viruses, archaea, and protozoa.

 Editor spotlight

Chief Editor, Professor Urakawa, is currently based at Florida Gulf Coast University as Professor of Marine and Ecological Sciences and has a background in Environmental Microbiology and Microbial Ecology.

 Special Issues

We currently have a number of Special Issues open for submission. Special Issues highlight emerging areas of research within a field, or provide a venue for a deeper investigation into an existing research area.

Latest Articles

More articles
Research Article

Serotype Distribution and Antimicrobial Resistance Profile of Haemophilus influenzae Isolated from School Children with Acute Otitis Media

Haemophilus influenzae is a Gram-negative opportunistic bacterial pathogen of the human respiratory tract. This study describes the prevalence, serotype distribution, and susceptibility profiles of H. influenzae strains isolated from the nasopharynx of school children with acute otitis media (AOM) in Banyumas Regency, Central Java, Indonesia. H. influenzae was isolated from nasopharyngeal swab specimens using chocolate agar plates supplemented with IsoVitaleX and bacitracin. Serotyping was performed using quantitative polymerase chain reaction. Antimicrobial susceptibility profiles were determined using a microdilution broth assay. H. influenzae was present in 69.7% of samples (85/122). Nontypeable H. influenzae (NHTi) was the most common serotype (95.3%), followed by H. influenzae type b (3.5%) and H. influenzae type f (1.2%). All the H. influenzae isolates were susceptible to levofloxacin, ceftriaxone, imipenem, meropenem, cefuroxime, and cefixime. Most isolates were susceptible to sparfloxacin (99%), cefepime (99%), amoxicillin/clavulanic acid 2 : 1 (99%), ampicillin/sulbactam 2 : 1 (96%), chloramphenicol (94%), tetracycline (93%), ampicillin (87%), and clarithromycin (82%). Nineteen percent of the isolates were resistant to cotrimoxazole, and 11% of the isolates were resistant to ampicillin. This study showed that H. influenzae carriage among samples was dominated by NTHi and less susceptible to cotrimoxazole.

Review Article

New Insights into the Taxonomy of Bacteria in the Genomic Era and a Case Study with Rhizobia

Since early studies, the history of prokaryotes taxonomy has dealt with many changes driven by the development of new and more robust technologies. As a result, the number of new taxa descriptions is exponentially increasing, while an increasing number of others has been subject of reclassification, demanding from the taxonomists more effort to maintain an organized hierarchical system. However, expectations are that the taxonomy of prokaryotes will acquire a more stable status with the genomic era. Other analyses may continue to be necessary to determine microbial features, but the use of genomic data might be sufficient to provide reliable taxa delineation, helping taxonomy to reach the goal of correct classification and identification. Here we describe the evolution of prokaryotes’ taxonomy until the genomic era, emphasizing bacteria and taking as an example the history of rhizobia taxonomy. This example was chosen because of the importance of the symbiotic nitrogen fixation of legumes with rhizobia to the nitrogen input to both natural ecosystems and agricultural crops. This case study reports the technological advances and the methodologies used to classify and identify bacterial species and indicates the actual rules required for an accurate description of new taxa.

Research Article

Campylobacter jejuni from Slaughter Age Broiler Chickens: Genetic Characterization, Virulence, and Antimicrobial Resistance Genes

Campylobacter jejuni is a major cause of food-borne human gastroenteritis worldwide and is designated as a high priority antimicrobial-resistant pathogen by the World Health Organization (WHO). In this study, a total of 26 C. jejuni isolates from broiler chickens were screened for the presence of virulence and antimicrobial resistance genes by PCR. As a result, the study detected 11/26 (42.3%), 9/26 (34.6%), 8/26 (30.8%), 7/26 (26.9%), 6/26 (23.1%), and 6/26 (23.1%) of cdtC, pldA, cdtB, cdtA, cadF, and ciaB virulence genes, respectively, with seven of the isolates carrying more than two virulence genes. The majority of the isolates n = 25 (96.1%) were resistant to nalidixic acid, followed by n = 21 (80.7%), n = 22 (84.6%), and n = 5 (19.2%) for tetracycline, erythromycin, and ciprofloxacin, respectively. Most isolates were harboring catI (n = 16; 84.2%), catII (n = 15; 78.9%), catIII (n = 10; 52.6%), catIV (n = 2; 10.5%), floR (n = 10; 52.6%), ermB (n = 14; 73.7%), tetO (n = 13; 68.4%), tetA (n = 9; 47.4%), mcr-4 (n = 8; 42.1%), and ampC (n = 2; 10.5%). Meanwhile, mcr-1, mcr-2, mcr-3, mcr-5, tet(X), tet(P), and tet(W) genes were not detected in all isolates. Class I and Class II integrons were detected in 92.3% (n = 24) and 65.4% (n = 17) isolates, respectively. About 31% (8 of the 26 isolates) isolates were carrying more than two resistance genes. According to our knowledge, this is the first study to detect class II integrons in Campylobacter spp. (C. jejuni). The high prevalence of cdtA, cdtB, cdtC, cadF, pldA, and ciaB genes and antibiotic resistance genes in C. jejuni in this study indicates the pathogenic potential of these isolates. Majority of the isolates demonstrated resistance to nalidixic acid, tetracycline (tet), and erythromycin (ermB), which are the drugs of choice for treating Campylobacter infections. Therefore, these findings highlight the importance of implementing an efficient strategy to control Campylobacter in chickens and to reduce antimicrobial use in the poultry industry, which will help to prevent the spread of infections to humans.

Research Article

Antimicrobial Activity of Aspergillus sp. from the Amazon Biome: Isolation of Kojic Acid

The antimicrobial potential of Aspergillus sp., isolated from the Amazon biome, which is stored at the Amazon Fungi Collection-CFAM at ILMD/FIOCRUZ, was evaluated. The fungal culture was cultivated in yeast extract agar and sucrose (YES) for cold extraction of the biocompounds in ethyl acetate at 28 °C for 7 days in a BOD type incubator. The obtained extract was evaluated for its antimicrobial activity against Candida albicans and Gram-positive and negative bacteria by the “cup plate” method and the determination of the minimum inhibitory concentration (MIC) by the broth microdilution method. The extract was subjected to thin layer chromatography (TLC) and fractionated by open and semipreparative column chromatography. The fractions of interest had their chemical constituents elucidated by nuclear magnetic resonance and mass spectrometry. The elucidated molecule was evaluated for cytotoxicity against the human fibroblast strain (MRC5). The extract presented inhibitory activity against both Gram-positive and negative bacteria, with the range of inhibition halos from 5.3 to 14 mm in diameter and an MIC ranging from 500 to 15.6 μg/mL. Seventy-one fractions were collected and TLC analysis suggested the presence of substances with double bond groups: coumarins, flavonoids, phenolic, alkaloids, and terpenes. NMR and MS analyses demonstrated that the isolated molecule was kojic acid. The results of the cytotoxicity test showed that MRC5 cells presented viability at concentrations from 500 to 7.81 μg/mL. The kojic acid molecule of Aspergillus sp., with antibacterial activity and moderate toxicity at the concentrations tested, is a promising prototype of an alternative active principle of an antimicrobial drug.

Research Article

Clinical Accuracy of Instrument-Read SARS-CoV-2 Antigen Rapid Diagnostic Tests (Ag-IRRDTs)

This systematic review (PROSPERO registration number: CRD42021282476) aims to collect and analyse current evidence on real-world performance based on clinical accuracy of instrument-read rapid antigen diagnostic tests (Ag-IRRDTs) for SARS-CoV-2 identification. We used PRISMA Checklist and searched databases (PubMed, Web of Science Core Collection and FIND) for publications evaluating the accuracy of SARS-CoV-2 Ag-IRRDTs as of 30 September 2021, and included 40 independent clinical studies resulting in 48 Ag-IRRDT datasets with 137,770 samples. Across all datasets, pooled Ag-IRRDT sensitivity was 67.1% (95% CI: 65.9%–68.3%) and specificity was 99.4% with a tight CI. Pooled sensitivity and specificity of SARS-CoV-2 Ag-IRRDTs did not demonstrate a significant superiority over SARS-CoV-2 rapid antigen tests which do not require a reader instrument, even in the case where surveillance and screening datasets were excluded from the analysis. Nevertheless, they provide connectivity advantages and remove operator interface (in results-reading) issues. The lower sensitivity of certain brands of Ag-IRRDTs can be overcome in high prevalence areas with high frequency of testing. New SARS-CoV-2 variants are major concern for current and future diagnostic performance of these tests.

Research Article

Cultivation of Different Oyster Mushroom (Pleurotus species) on Coffee Waste and Determination of Their Relative Biological Efficiency and Pectinase Enzyme Production, Ethiopia

Cultivation of specialty mushrooms on lignocellulosic wastes represents one of the most economic and cost-effective organic recycling processes. Solid-state cultivation (SSC) was carried out to evaluate the feasibility of using coffee waste (husk and parchment) as substrate for cultivation of oyster mushroom (Pleurotus species). The periods for spawn running, pinhead and fruit body formation, number of flushes, yield, and biological efficiency of the four Pleurotus species (P. citrinopileatus, P. eryngii, P. ostreatus, and P. sapidus) grown on coffee husk and parchment were studied. The results revealed that the time for the first appearance of pinhead was shortest for P. ostreatus (20–21) days followed by P. sapidus (22–23) days on coffee husks, while P. eryngii and P. citrinopileatus required 26–27 days and 23–24 days, respectively, on the some substrate. All the four Pleurotus species recorded at least four flushes and three flushes on coffee husk and parchment, respectively; flush 1 gave the highest yield while flush 3 and 4 gave the lowest yield. The biological efficiency (B.E.) for P. citrinopileatus, P. eryngii, P. ostreatus and P. sapidus obtained from fresh coffee husk was 26.54, 40.94, 60.33, and 55.72, respectively. Significant differences () in yield and % B.E. of the four mushrooms species were recorded. The results also showed that the B.E. (61.92%) of P. ostreatus grown on composted coffee husk was insignificantly higher () than that grown on noncomposted coffee husk (60.33). The yields of P. sapidus obtained from the two substrates were almost comparable with that of P. ostreatus. There was a significant difference at () observed between noncomposted and composted coffee husk and coffee parchment as well as between coffee husk and coffee parchment on yield and biological efficiency (B.E.). Composted coffee waste is more efficient than noncomposted one. Pectinase enzymes productions by these mushrooms were also studied. They are known to produce extracellular enzymes, particularly pectinase, which contribute to the biochemical decomposition of pectin-rich lignocellulosic wastes biomass. Accordingly, P. sapidus showed more pectolytic activities followed by P. ostreatus. But the pectolytic activity showed by P. eryngii and P. citrinopileatus was relatively lower. The implications of this study are the feasibility of using composted coffee husks and coffee parchment with the supplementary substrate to cultivate very protein-rich mushrooms for food in solid-state cultivation (SSC) while at the same time promoting environmental sustainability.

International Journal of Microbiology
 Journal metrics
See full report
Acceptance rate15%
Submission to final decision74 days
Acceptance to publication16 days
CiteScore3.000
Journal Citation Indicator0.610
Impact Factor-
 Submit

Article of the Year Award: Outstanding research contributions of 2020, as selected by our Chief Editors. Read the winning articles.