Identification Of Microorganisms Research Articles

Hot spots and trends in microbial disease research on cultural heritage: a bibliometric analysis.

This study is to understand and analyze the development history, research hotspots, and research trends in the study of microbial diseases of cultural heritage through bibliometric analyses in order to fill the current gap of no literature review in this research field and to make certain contributions to the research in this field and the protection of cultural heritage. Bibliometric and visual analyses of the literature on cultural heritage microbial diseases in the Web of Science (WoS) core collection were carried out using VOSviewer and R-bibliometrix, choosing the two main literature types of papers and reviews. The emphasis was placed on analyzing and summarizing core research strengths, hotspots, and trends. Six hundred sixty-seven documents (573 articles and 94 reviews) were retrieved. αIn the WoS core collection, the first literature on cultural heritage microbial disease research was published in January 2000, and the annual number of publications from 2000 to 2009 did not exceed one; the annual number of publications from 2010 onwards increased rapidly, and after 2018, the number of publications per year exceeded 60, reaching 94 in 2020, which indicates that cultural heritage microbial disease research is booming. Our research showed that Italy, the USA, and China were the leading research countries, and Univ Milan was the institution with the most publications. International Biodeterioration &Biodegradation was the most published and co-cited journal, and Gu JD was the most prolific author. The research hotspots in the study of microbial diseases of cultural heritage mainly include biological degradation of cultural heritage; identification of diseased microorganisms and disease mechanisms; cultural heritage microbial disease prevention and control methods; monitoring, prevention, and control of diseased microorganisms in indoor air; antibacterial agents, especially essential oils, nanoparticles, and other safe and efficient antibacterial products research and development; and exploration of the mechanisms of biofilm protection of cultural heritage on cultural heritage surfaces. Monitoring and identifying cultural heritage microbial communities, identifying disease mechanisms, and researching safe and efficient bacteriostatic products such as essential oils and nanoparticles will be the main research directions in the field of cultural heritage microbial disease prevention and control in the future.

Multiplexing the Identification of Microorganisms via Tandem Mass Tag Labeling Augmented by Interference Removal through a Novel Modification of the Expectation Maximization Algorithm.

Having fast, accurate, and broad spectrum methods for the identification of microorganisms is of paramount importance to public health, research, and safety. Bottom-up mass spectrometer-based proteomics has emerged as an effective tool for the accurate identification of microorganisms from microbial isolates. However, one major hurdle that limits the deployment of this tool for routine clinical diagnosis, and other areas of research such as culturomics, is the instrument time required for the mass spectrometer to analyze a single sample, which can take ∼1 h per sample, when using mass spectrometers that are presently used in most institutes. To address this issue, in this study, we employed, for the first time, tandem mass tags (TMTs) in multiplex identifications of microorganisms from multiple TMT-labeled samples in one MS/MS experiment. A difficulty encountered when using TMT labeling is the presence of interference in the measured intensities of TMT reporter ions. To correct for interference, we employed in the proposed method a modified version of the expectation maximization (EM) algorithm that redistributes the signal from ion interference back to the correct TMT-labeled samples. We have evaluated the sensitivity and specificity of the proposed method using 94 MS/MS experiments (covering a broad range of protein concentration ratios across TMT-labeled channels and experimental parameters), containing a total of 1931 true positive TMT-labeled channels and 317 true negative TMT-labeled channels. The results of the evaluation show that the proposed method has an identification sensitivity of 93-97% and a specificity of 100% at the species level. Furthermore, as a proof of concept, using an in-house-generated data set composed of some of the most common urinary tract pathogens, we demonstrated that by using the proposed method the mass spectrometer time required per sample, using a 1 h LC-MS/MS run, can be reduced to 10 and 6 min when samples are labeled with TMT-6 and TMT-10, respectively. The proposed method can also be used along with Orbitrap mass spectrometers that have faster MS/MS acquisition rates, like the recently released Orbitrap Astral mass spectrometer, to further reduce the mass spectrometer time required per sample.

Isolation and Identification of Microorganisms Associated with Pap and Stored Corn Starch

This study isolated and identified microorganisms associated with pap and stored corn starch. This was done to help portray spoilage microorganisms associated with stored corn starch and pap. The study was achieved through laboratory analysis of pap sample and stored sample over a period of 7days. Result obtained shows that the pap samples are contaminated with bacteria. The profile of bacteria evaluated shows an increasing trend over the retention period with isolates of bacteria such as Pseudomonas sp., Bacillus sp and Lactobacillus sp. which are not entirely eliminated when prepared in heat (pap). The isolation of fungi from the pap samples revealed that it could serve as a means for the transmission of potentially pathogenic microorganisms. However, fungi isolates such Rhizopus sp. and Aspergillus sp. was not present in pap due to the fact that they are mesophilic fungi and cannot survive at temperature ranges above 60OC. Comparison of samples showed that pap preparation is an efficient technique for elimination of fungi but significantly ineffective in complete elimination of bacteria. It can therefore be concluded that cooking of pap does not entirely eliminate pathogenic microbes and hence caution should be taken in pap consumption.

Physical-chemical and microbiological characterization of water destined to hemodialysis

This research evaluated the physical-chemical and microbiological parameters of water and dialysate in four distinct hemodialysis units located in the southeast region of Brazil. The physical-chemical parameters evaluated were pH, electric conductivity, turbidity, alkalinity, free chlorine, nitrate, fluoride, chloride, sulfate, sodium, potassium, calcium, and magnesium ion concentrations. Microcystin was also quantified. The microbiological parameters evaluated were the detection of total coliform, total heterotrophic bacteria count (THB), and the isolation and identification of microorganisms in pre-reverse osmosis treatment and post-reverse osmosis treatment water samples and dialysate. The nitrate, fluoride and THB levels found in the water samples may present risk to the patient under hemodialysis treatment. Microcystin was detected in one of the potable water samples. Microorganisms were identified throughout the hemodialysis of the entire water treatment system, with Ralstonia sp. being the most frequent. The presence of emergent pathogenic bacteria highlighted in this study highlights the necessity of microbiological monitoring of water destined for hemodialysis. Keywords: dialysate, hemodialysis, water treatment.

Identification of Microorganism in Infected Wounds by Positively Charged Selective Sensor Array and Deep Learning Algorithm.

Microorganism are ubiquitous and intimately connected with human health and disease management. The accurate and fast identification of pathogenic microorganisms is especially important for diagnosing infections. Herein, three tetraphenylethylene derivatives (S-TDs: TBN, TPN, and TPI) featuring different cationic groups, charge numbers, emission wavelengths, and hydrophobicities were successfully synthesized. Benefiting from distinct cell wall binding properties, S-TDs were collectively utilized to create a sensor array capable of imaging various microorganisms through their characteristic fluorescent signatures. Furthermore, the interaction mechanism between S-TDs and different microorganisms was explored by calculating the binding energy between S-TDs and cell membrane/wall constituents, including phospholipid bilayer and peptidoglycan. Using a combination of the fluorescence sensor array and a deep learning model of residual network (ResNet), readily differentiation of Gram-negative bacteria (G-), Gram-positive bacteria (G+), fungi, and their mixtures was achieved. Specifically, by extensive training of two ResNet models with large quantities of images data from 14 kinds of microorganism stained with S-TDs, identification of microorganism was achieved at high-level accuracy: over 92.8% for both Gram species and antibiotic-resistant species, with 90.35% accuracy for the detection of mixed microorganism in infected wound. This novel method provides a rapid and accurate method for microbial classification, potentially aiding in the diagnosis and treatment of infectious diseases.

Clinical Situation, Species Distribution, and Antibiotic Resistance of Pathogenic Bacteria and Fungi in 626 Cases of Vulvovaginitis in Hangzhou, China.

Female vulvovaginitis was one of the most common gynecological diseases. It had a great negative impact on their work and quality of life. This retrospective study evaluated the clinical and laboratory data of patients with vulvovaginitis in Hangzhou, China. To analyze the clinical situation, species distribution and antibiotic resistance of pathogenic fungi and bacteria in 626 cases of vulvovaginitis in Hangzhou. Microorganism culture, identification, and antibiotic susceptibility testing were conducted. The study aimed to provide a theoretical value for an effective treatment of vulvovaginitis. In total, 626 outpatients and inpatients diagnosed with vulvovaginitis were selected from January 2018 to January 2023. Data of all the patients were collected from the hospital's electronic medical records. Vaginal secretion was collected for testing and SPSS 25.0 software was used to perform statistical analysis. A total of 626 strains of fungi, Gram-positive, and -negative bacteria were detected. Clinical situations of patients infected with the top five pathogenic fungi and bacteria were analyzed. Pathogenic fungi and bacteria were slightly different in each age group and in each onset time group. The results of antibiotic susceptibility testing showed that the resistance rates of itraconazole and fluconazole were high and Gram- negative and -positive bacteria were multidrug resistant. Gram-negative bacteria were more sensitive to carbenicillins and compound antibiotics, while Gram-positive bacteria were sensitive to rifampicin and daptomycin. MRSA and non vancomycin-resistant strains were detected. Fungi and bacteria were usually detected as pathogenes in patients with vulvovaginitis in Hangzhou. Some factors, such as age and onset time, often affected the incidence. Pathogenic fungi and bacteria were resistant to some common antibiotics, and clinical treatments should be carried out in a timely and reasonable manner according to the results of antibiotic susceptibility testing.

Isolation and characterization of Stenotrophomonas pavanii GXUN74707 with efficient flocculation performance and application in wastewater treatment.

The identification of microorganisms with excellent flocculants-producing capability and optimization of the fermentation process are necessary for the wide-scale application of bioflocculants. Therefore, we isolated and identified a highly efficient flocculation performance strain of Stenotrophomonas pavanii GXUN74707 from the sludge. The optimal fermentation and flocculation conditions of strain S. pavanii GXUN74707 was in fermentation medium with glucose and urea as the carbon and nitrogen sources, respectively, at pH 7.0 for 36 h, which treatment of kaolin suspension with 0.5 mL of the fermentation broth resulted in a flocculation rate of 99.0%. The bioflocculant synthesized by strain S. pavanii GXUN74707 was found mainly in the supernatant of the fermentation broth. Chemical analysis revealed that the pure bioflocculant consisted of 79.70% carbohydrates and 14.38% proteins. The monosaccharide components of MBF-GXUN74707 are mainly mannose (5.96 μg/mg), galactose (1.86 μg/mg), and glucose (1.73 μg/mg). Infrared spectrometric analysis showed the presence of carboxyl (COO-), hydroxyl (-OH) groups. The SEM images showed clumps of rod-shaped bacteria with adhesion of extracellular products. Furthermore, the strain decolored dye wastewater containing direct black, direct blue, and Congo red by 89.2%, 95.1%, 94.1%, respectively. The chemical oxygen demand (COD) and biological oxygen demand (BOD) removal rates after treatment of aquaculture wastewater with the fermentation broth were 68% and 23%, respectively. This study is the first to report the performance and application of strain Stenotrophomonas pavanii in wastewater flocculation. The results indicate that strain S. pavanii is a good candidate for the production novel bioflocculants and demonstrates its potential industrial practicality in biotechnology processes.

Evaluation of the Role of Oral Microbes in Pathogenesis of Oral Lichen Planus

ABSTRACT Background: The pathophysiology and etiology of oral lichen planus (OLP) are still unknown, despite the fact that the condition’s progression has been connected to a T-cell-based immune response. Research has focused on variables, such as oral bacteria, that may cause an autoimmune reaction with conflicting results. Aim: This study was conducted to evaluate the role of oral microorganisms in the pathogenesis of OLP. Materials and Methods: In this study, 82 formalin-fixed paraffin-embedded specimens of histopathologically confirmed cases of OLP and 20 such specimens of normal healthy subjects were obtained. Immunohistochemistry was carried out for the identification of microorganisms. Results: Candida albicans was observed in 47.12% of OLP cases and 9.43% of healthy controls. Helicobacter pylori was discovered in 45.21% of OLP cases and 13.46% of healthy controls. Periodontopathogenic bacteria was found in 33.14% of OLP cases and 13.45% of healthy controls. Human papillomavirus (HPV)-16 was noticed in 38.12% of OLP cases and 11.24% in the control group. HPV-18 was found in 32.43% of OLP patients and 11.43% in the control group. Mycoplasma salivarium was found in 46.47% of OLP patients and 6.45% in control. Conclusion: It was observed that several microorganisms like H. pylori, C. albicans, M. salivarium, periodontopathogenic bacteria, HPV-16, and HPV-18 were found to be related to OLP.

Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry: An Innovative Tool for Rapid Identification of Hylurgus ligniperda, an Invasive Pest

Hylurgus ligniperda is an imported quarantine plant pest in China. Its identification is usually based on morphological characteristics; therefore, species identification needs high professional requirements of staff and professionals with high experience accumulated through long-term training. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid identification technology, which is based on protein profiles of species. It has been widely used for the identification of pathogenic microorganisms. Many studies have reported the identification of mosquitoes, ticks, and other arthropods. The application of MALDI-TOF MS in the identification of H. ligniperda can improve the identification efficiency of H. ligniperda, preventing and control its harm and further spread. To construct a spectra database for H. ligniperda, we analyzed the effect of different factors, such as different body parts, developmental stages, populations, and preservation conditions, on its protein spectrum. We collected protein spectrum profiles from 19 specimens of H. ligniperda and its related species, obtaining 211 protein spectra to construct a reference database and validate identification. The protein spectrum from the chest specimens of H. ligniperda showed many peaks, high intensity, and a stable signal, indicating a successful data establishment. The difference in protein spectra between different regions of the same species was less, but did not affect the identification results. Clear differences were observed in the protein spectrum across many developmental stages. The database established by the adult specimens protein spectrum can accurately identify Dendroctonus valens, Tomicus piniperda, and H. ligniperda. MALDI-TOF MS technology can be used for the rapid identification of H. ligniperda. This method is rapid and direct, and the identification results are robust. It does not require specialized entomological expertise and can be used for customs interception and field investigations.

Geospatial evaluation and bio-remediation of heavy metal-contaminated soils in arid zones

Introduction: Soil pollution directly impacts food quality and the lives of both humans and animals. The concentration of heavy metals in Egypt’s drain-side soils is rising, which is detrimental to the quality of the soil and crops. The key to reducing the detrimental effects on the ecosystem is having accurate maps of the spatial distribution of heavy metals and the subsequent use of environmentally sustainable remediation approaches. The objective of this work is to assess soil contamination utilizing spatial mapping of heavy metals, determine contamination levels using Principal Component Analysis (PCA), and calculate both the contamination severity and the potential for bioremediation in the soils surrounding the main drain of Bahr El-Baqar. Furthermore, evaluating the capacity of microorganisms (bacteria, fungi, and “Actinomycetes) to degrade heavy elements in the soil.Methodology: 146 soil sample locations were randomly selected near the Bahr El-Baqar drain to examine the degree of soil pollution Ordinary Kriging (OK), method was used to map and analyze the spatial distribution of soil contamination by seven heavy metals (Cr, Fe, Zn, Cd, Pb, As, and Ni). Modified contamination degree (mCd) and PCA were used to assess the research area’s soil pollution levels. The process involved isolating, identifying, and classifying the microorganisms present in the soil of the study area. The study findings showed that variography suggested the Stable model effectively matched pH, SOM, and Cd values. Furthermore, the exponential model proved suitable for predicting Fe, Pb and Ni, while the spherical model was appropriate for Ni, Cr, and Zn.Results: The study revealed three levels of contamination, with an extremely high degree (EHDC) affecting approximately 97.49% of the area. The EHDC exhibited average concentrations of heavy metals: 79.23 ± 17.81 for Cr, 20,014.08 ± 4545.91 for Fe, 201.31 ± 112.97 for Zn, 1.33 ± 1.37 for Cd, 40.96 ± 26.36 for Pb, 211.47 ± 13.96 for As, and 46.15 ± 9.72 for Ni. Isolation and identification of microorganisms showed a significant influence on the breakdown of both organic and inorganic pollutants in the environment. The study demonstrated exceptionally high removal efficiency for As and Cr, with a removal efficiency reached 100%, achieved by Rhizopus oryzae, Pseudomonas aeruginosa, and Bacillus thuringiensis.Conclusion: This study has designated management zones for soil contamination by mapping soil pollutants, geo-identified them, and found potential microorganisms that could significantly reduce soil pollution levels.

Molecular Identification of Endophytic Fungi Isolated from Bidara Root (Ziziphus mauritiana Lam.) Using Polymerase Chain Reaction (Pcr)

The roots of the bidara plant have the potential as antibacterial agents. The antibacterial compounds in the roots of the bidara plant originate from secondary metabolites produced by endophytic compounds known as endophytic fungi. The purpose of this research is to identify the types of endophytic fungi in bidara roots. The identification of microorganisms can be done through morphology or molecular methods. However, morphological identification alone is unable to depict the morphospecies to the phylogenetic level of a microorganism, thus molecular identification using the Polymerase Chain Reaction (PCR) method is required. This study utilized root isolates from the bidara plant with the sample code IFAZ-6, which, after sequencing, yielded a pair of base pairs measuring 558bp. The results of BLAST and phylogenetic analysis revealed that the IFAZ-6 isolate has a close relationship with the species Clonostachys rosea., which has been recorded in the database with a 100% identity level.

Microbial keratitis in Southern Malawi: a microbiological pilot study.

Microbial keratitis (MK) is a significant cause of blindness in sub-Saharan Africa. We investigated the feasibility of using a novel corneal impression membrane (CIM) for obtaining and processing samples by culture, PCR and whole-genome sequencing (WGS) in patients presenting with suspected MK in Malawi. Samples were collected from patients presenting with suspected MK using a 12 mm diameter polytetrafluoroethylene CIM disc. Samples were processed using culture and PCR for Acanthamoeba, herpes simplex virus type 1 (HSV-1) and the bacterial 16S rRNA gene. Minimum inhibitory concentrations of isolates to eight antimicrobials were measured using susceptibility strips. WGS was used to characterise Staphylococcus aureus isolates. 71 eyes of 71 patients were included. The overall CIM isolation rate was 81.7% (58 positive samples from 71 participants). 69 (81.2%) of isolates were Gram-positive cocci. Coagulase-negative Staphylococcus 31.8% and Streptococcus species 14.1% were the most isolated bacteria. Seven (9.9%) participants were positive for HSV-1. Fungi and Acanthamoeba were not detected. Moxifloxacin and chloramphenicol offered the best coverage for both Gram-positive and Gram-negative isolates when susceptibility was determined using known antimicrobial first quartile concentrations and European Committee on Antimicrobial Susceptibility Testing breakpoints, respectively. WGS identified known virulence genes associated with S. aureus keratitis. In a resource-poor setting, a CIM can be used to safely sample the cornea in patients presenting with suspected MK, enabling identification of causative microorganisms by culture and PCR. Although the microbiological spectrum found was limited to the dry season, these preliminary results could be used to guide empirical treatment.

Isolation and identification of microorganisms associated with fairly used clothes (Okirika) sold in Eke Awka Market, Anambra State

The use of previously worn clothing poses a risk of transmitting infectious diseases as the history of previous users is unknown. Despite this, used clothes are commonly sold as they are cheaper compared to new ones. Research was carried out to investigate the presence of pathogenic microbes such as bacteria, fungi, and protozoa in used clothes bought at Eke Awka Market in Anambra State, Nigeria. A variety of clothing items, including trousers, shirts, caps, bras, panties, baby clothes, towels, socks, head ties, and bed sheets were purchased and analysed for the presence of contaminating microbes. Techniques such as culture and plate count methods were used for the isolation of these microorganisms, and further identification was done through morphological and biochemical methods. Additionally, protozoa were specifically isolated through a washing method, which involved centrifuging the samples at 500g for 10 minutes and then observing the sediments under a microscope. The study found microorganisms such as Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus spp, Rhodoborula spp, Candida glabrata and Entamoeba coli on the clothes examined. The highest number of bacteria isolates (2.00±0.000) were from caps and socks while the least (1.00±0.000) were from bras and bed sheets. The highest number of fungi isolates (2.50±0.707) were from trousers, bras, and baby cloths while shirts, socks, and bed sheets had the least number of fungi isolates (1.00±0.000). The only protozoan isolate was found in socks. In terms of colonies formed per unit, panties had the most colony-forming units (132.5±10.607) for fungi and (63.5±4.95) for bacteria organisms while caps had the least (16±1.414) for fungi and (8.5±2.121) for bacteria organisms, respectively. It is important to note that used clothes can act as a bearer of harmful bacteria for the epidermis and other diseases and should, whenever possible, be washed and sanitized thoroughly before use.

Yeast Diversity in Honey and Pollen Samples from Stingless Bees in the State of Bahia, Brazil: Use of the MALDI-TOF MS/Genbank Proteomic Technique.

(1) Background: The identification of microorganisms includes traditional biochemical methods, molecular biology methods evaluating the conserved regions of rRNA, and the molecular biology of proteins (proteomics), such as MALDI-TOF MS mass spectrometry. This work aimed to identify the biodiversity of yeasts associated with stingless bee species' honey and pollen, Melipona scutellaris, Nannotrigona testaceicornes, and Tetragonisca angustula, from the region of São Gonçalo dos Campos-Bahia (BA) state, Brazil. (2) Methods: Cellular proteins were extracted from 2837 microbial isolates (pollen and honey) and identified via MALDI-TOF MS. The identified yeast species were also compared to the mass spectra of taxonomically well-characterized reference strains, available from the National Center of Biotechnology Information (NCBI) database. (3) Results: Nine yeast species were identified: Candida maltosa, Candida norvegica, Kazachstania telluris, Schizosaccharomyces pombe, Scheffersomyces insectosus, Meyerozyma guilliermondii, Brettanomyces bruxellensis, Kazachstania exigua, and Starmerella lactis-condensi. Nannotrigona testaceicornes pollen had the highest number of yeast colonies. The yeasts Brettanomyces bruxellensis and Kazachstania telluris showed high populations in the samples of Nannotrigona testaceicornes and Melipona scutellaris, respectively. This work shows that there is some sharing of the same species of yeast between honey and pollen from the same beehive. (4) Conclusions: A total of 71.84% of the identified species present a high level of confidence at the species level. Eight yeast species (Candida maltosa, Candida norvegica, Kazachstania telluris, Schizosaccharomyces pombe, Scheffersomyces insectosus, Meyerozyma guilliermondii, Kazachstania exigua, and Starmerella lactis-condensi) were found for the first time in the samples that the authors inspected. This contributes to the construction of new knowledge about the diversity of yeasts associated with stingless bee products, as well as to the possibility of the biotechnological application of some yeast species.

Machine Learning-Assistant Colorimetric Sensor Arrays for Intelligent and Rapid Diagnosis of Urinary Tract Infection.

Urinary tract infections (UTIs), which can lead to pyelonephritis, urosepsis, and even death, are among the most prevalent infectious diseases worldwide, with a notable increase in treatment costs due to the emergence of drug-resistant pathogens. Current diagnostic strategies for UTIs, such as urine culture and flow cytometry, require time-consuming protocols and expensive equipment. We present here a machine learning-assisted colorimetric sensor array based on recognition of ligand-functionalized Fe single-atom nanozymes (SANs) for the identification of microorganisms at the order, genus, and species levels. Colorimetric sensor arrays are built from the SAN Fe1-NC functionalized with four types of recognition ligands, generating unique microbial identification fingerprints. By integrating the colorimetric sensor arrays with a trained computational classification model, the platform can identify more than 10 microorganisms in UTI urine samples within 1 h. Diagnostic accuracy of up to 97% was achieved in 60 UTI clinical samples, holding great potential for translation into clinical practice applications.

Distribution ofListeria spp., andListeria monocytogenesin micro- and small-scale meat product processing plants

Listeriosis is a disease caused by L. monocytogenes, a relevant microorganism as a causative agent of foodborne diseases - FBD. This study aimed to evaluate the distribution of Listeria spp., and L. monocytogenes in different production areas in two small plants (A and B) and two micro-food processing plants (C and D) producing meat derivatives, located in different cities of Colombia. The methodology implemented was i. The analysis of sampling points is based on a harmonised tool. ii. Four samplings in each production plant between 2019 and 2020. iii. Isolation and identification of microorganisms through conventional microbiology, a semi-automated system, molecular serotyping and clonal characterisation by ERIC-PCR. L. monocytogenes frequency in the production plants belonging to the study ranged between 5.9 and 28.6 %; for Listeria spp., plants A and D had isolated, plant A had the highest proportion, while for L. monocytogenes geno-serotypes found were: 1/2a, 1/2c, 4a-4c, 4b, 4d - 4e, with geno-serotype 4b as the most frequent. Furthermore, possible persistent isolates were detected in plant C as the feasible sources of contamination, based on failures in flow management, raw material contaminated with L. monocytogenes, lack of standardised cooking processes and transfer of the microorganism through equipment and surfaces. Finally, in three of the four production plants assayed, L. monocytogenes or Listeria spp. were present in the packaging area in some of the samples taken during the study, which calls for increased and frequent monitoring, as well as constant technical support for the control of L. monocytogenes in micro and small-scale production plants.

Antimicrobial Activity of Dimeric Flavonoids

Distributed throughout the environment are various microorganisms such as bacteria, fungi, parasites, and viruses. Although many are part of the human microbiome, many are pathogenic and cause infections ranging from mild to severe. In recent years, the identification of multidrug-resistant microorganisms has become a serious public health problem. The resulting infections call into question the therapeutic capacity of health systems and lead to approximately 70,000 deaths annually worldwide. The progressive resistance to antibiotics and antifungals has been a major challenge for the medical and pharmaceutical community, requiring the search for new compounds with antimicrobial properties. Several studies have demonstrated the potential of natural and synthesized flavonoids, especially the dimers of these molecules. In this review are presented many examples of dimeric flavonoids that have demonstrated antimicrobial activity against viruses, like influenza and Human Immunodeficiency Virus (HIV), protozoal infections, such as Leishmaniasis and Malaria, fungal infections by Candida albicans and Cryptococcus neoformans, and bacterial infections caused, for example, by Staphylococcus aureus and Escherichia coli. In the pursuit to find potential safe agents for therapy in microbial infections, natural dimeric flavonoids are an option not only for the antimicrobial activity, but also for the low toxicity usually associated with these compounds when compared to classic antimicrobials.

Pediococcus spp.-mediated competition interaction within Daqu microbiota determines the temperature formation and metabolic profiles.

Fermented microbiota is critical to the formation of microenvironment and metabolic profiles in spontaneous fermentation. Microorganisms generate a diverse array of metabolites concurrent with the release of heat energy. In the case of Daqu fermentation, the peak temperature exceeded 60°C, forming a typical high-temperature fermentation system known as high-temperature Daqu. However, microorganisms that cause the quality variation in Daqu and how they affect the functional microbiota and microenvironment in the fermentation process are not yet clear. This study adopted high-throughput sequencing and monitored the dynamic fluctuations of metabolites and environmental factors to identify the pivotal microorganism responsible for the alterations in interaction patterns of functional keystone taxa and quality decline in the fermentation system of different operational areas during the in situ fermentation process that had been mainly attributed to operational taxonomic unit (OTU)_22 (Pediococcus acidilactici). Additionally, we used isothermal microcalorimetry, plate inhibition experiments, and in vitro simulation fermentation experiments to explore the impact of Pediococcus spp. on heat generation, microorganisms, and metabolite profiles. Results showed the heat peak generated by Pediococcus spp. was significantly lower than that of Bacillus spp., filamentous fungi, and yeast. In addition, the preferential growth of P. acidilactici strain AA3 would obviously affect other strains to colonize through competition, and its metabolites made a significant impact on filamentous fungi. The addition of P. acidilactici strain AA3 in simulated fermentation would cause the loss of pyrazines and acids in metabolites. These evidences showed that the overgrowth of Pediococcus spp. greatly influenced the formation of high temperatures and compounds in solid-state fermentation systems. Our work illustrated the vital impact of interaction variability mediated by Pediococcus spp. for microbial assembly and metabolites, as well as in forming temperature. These results emphasized the functional role of Daqu microbiota in metabolites and heat production and the importance of cooperation in improving the fermentation quality.IMPORTANCEThe stable and high-quality saccharifying and fermenting starter in traditional solid-state fermentation was the prerequisite for liquor brewing. An imbalance of microbial homeostasis in fermentation can adversely impact production quality. Identification of such critical microorganisms and verifying their associations with other fermentation parameters pose a challenge in a traditional fermentation environment. To enhance the quality of spontaneous fermented products, strategies such as bioaugmentation or the control of harmful microorganisms would be employed. This work started with the differences in high-temperature Daqu metabolites to explore a series of functional microorganisms that could potentially contribute to product disparities, and found that the differences in interactions facilitated directly or indirectly by Pediococcus spp. seriously affected the development of microbial communities and metabolites, as well as the formation of the microenvironment. This study not only identified functional microbiota in Daqu that affected fermentation quality, but also demonstrated how microorganisms interact to affect the fermentation system, which would provide guidance for microbial supervision in the actual production process. Besides, the application of isothermal microcalorimetry in this study was helpful for us to understand the heat production capacity of microorganisms and their adaptability to the environment. This study presented a commendable framework for improving and controlling the quality of traditional fermentation and inspired further investigations in similar systems.

Clinical Characteristics and Microorganisms Isolated in Community-Acquired Pneumonia in the COVID-19 Period.

Community-acquired pneumonia is a leading cause of mortality and hospital admissions. The aetiology remains unknown in 30-65% of the cases. Molecular tests are available for multiple pathogen detection and are under research to improve the causal diagnosis. We carried out a prospective study to describe the clinical characteristics and aetiology of community-acquired pneumonia during the COVID-19 pandemic and to assess the diagnostic effectivity of the microbiological tests, including a molecular test of respiratory pathogens (FilmArray™ bioMérieux). From the 1st of February 2021 until the 31st of March 2022, 225 patients were included. Failure in microorganism identification occurred in approximately 70% of patients. Streptococcus pneumoniae was the most common isolate. There were 5 cases of viral pneumonia. The tested FilmArray exhibited a low positivity rate of 7% and mainly aided in the diagnosis of viral coinfections. Despite our extensive diagnostic protocol, there is still a low rate of microorganism identification. We have observed a reduction in influenza and other viral pneumoniae during the COVID-19 pandemic. Having a high NEWS2 score on arrival at the emergency department, an active oncohematological disease or chronic neurological conditions and a positive microbiological test result were related to worse outcomes. Further research is needed to determine the role of molecular tests in the microbiological diagnosis of pneumonia.

Nutritional and Microbial Qualities of Fermented Cereal-Based Porridges Produced in Northern Benin

Fermentation has been used for centuries to enhance the sensory and nutritional qualities and the antioxidant content of plant-based foods, making them beneficial for health. This study aims to investigate the microbiological and nutritional qualities of fermented porridges produced in northern Benin. Various nutritional tests and the identification of different microorganisms have gained insights into eight porridges produced in 9 localities of northern Benin. Lactic acid bacteria have the highest proportion among all microorganisms in fermented porridges, followed by the total mesophyll aerobic flora. E. coli, thermotolerant coliforms, and molds are not present in all porridges analyzed. Recorded data suggested that porridges have a variable microbial load depending on the collection municipalities. The dry matter of the eight types of porridge varies greatly, with akloui having 27.03 ± 3.83 g/100 g and fourra having 48.63 ± 3.83 g/100 g. The total ashes also differ significantly, with bita having 39.36 ± 4.67 g/100 g and sagagnèga having 63.19 ± 4.67 g/100 g. It is worth noting that all fermented porridges have a pH lower than 5, and the titratable acidity ranges from 0.01 ± 0.00 g to 0.02 ± 0.00 g. The brix degree varies from 0.46 ± 0.54 to 4.4 ± 0.54. The beta-carotene values of the 8 types of porridge vary from 0.037 ± 0.018 mg/g to 0.138 ± 0.018 mg/g, while the total sugars range from 1.926 ± 0.877 to 5.773 ± 0.877 g/100 g. The lipid content, when present, varies from 0.226 ± 0.029% to 0.408 ± 0.029%. Finally, the protein percentage of the porridge ranges from 7.061 ± 0.779 to 12.419 ± 0.779.