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Protein Characterization, Functional Annotation, Active Site Analysis of Novel Uncharacterized Conserved Protein of Bacteroides xylanisolvens: An In Silico Approach

Bacteroides xylanysolvens is a gram-negative, anaerobic rod alongside xylan-degrading bacterium identified from human feces samples. An In silico technique can help us better comprehend the uncharacterized protein of Bacteroides xylanysolvens (accession ID: CUN90054) by examining its functional annotations, identification, and structural characterization. In silico pathways are used to investigate the protein's physiochemical properties, functional annotation, structure prediction, active site analysis, and sub-cellular localization. The annotated hypothetical protein is connected to Metal-independent alpha-mannosidase (MIAM) including both bacterial and fungal glycoside hydrolases (GH125), according to the current study. This finding may be of considerable relevance to future bacterial genetics research.

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Microbial Heat Shock Proteins: Roles other than Just Stress Proteins
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Heat Shock Proteins are so named stress proteins or stress molecules due to their secretion triggered by stress encountered by living beings. Although their primary documented role has been maintaining and regulating protein conformations to reduce effects of aberrant conditions faced by the host, heat shock proteins have been found to have therapeutic effects in treatments of many diseases and conditions. Those derived from certain bacteria, in particular, have been found to have high immunomodulatory potential and are being considered as adjuvants and immunostimulators in immunocompromised individuals. Extensive research has been done establishing their role as potential vaccine antigens or epitopes targeted in cancer therapies. Certain neuropathies and assumed incurable auto immune diseases have also seen light in terms of therapeusis mediated by heat shock proteins. This review focuses on giving an extensive study about multiple moonlighting roles of heat shock proteins derived from microorganisms, at molecular level, which are being used to immunize and treat diseases in many mammalian species, including humans.

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Antimicrobial properties of select plant species within the Asteraceae Family

The Asteraceae family stands as the largest among flowering plants, encompassing over 1,600
genera grouped into 17 tribes and distributed across the globe. 25,000 different plant species
are represented in the global distribution, 750 of which are native to Madagascar. Among the
flowers and leaves of numerous plants within this family, reports have surfaced about their
potential antibacterial, antifungal, antiviral, and anti-inflammatory properties. This has led to
their integration into traditional medicinal practices. This particular research aimed to
evaluate the antibacterial effectiveness of 12 native plants from the Asteraceae family. These
included 11 species from the Helichrysum genus and one species from the Catatia genus.
Their efficacy was tested against 11 bacterial strains.
The methodology employed the liquid microdilution technique to establish the minimum
inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the crude
methanolic extracts obtained from each plant. The findings unveiled that all 12 plant species
exhibited MIC values ranging from 0.125 to 1 mg/ml, while their MBC values ranged from
0.25 to 4 mg/ml. This demonstrated their effectiveness against a range of bacterial strains,
encompassing two Gram-negative strains (E. cloacae and P. mirabilis) as well as four Gram-
positive strains (L. monocytogenes, B. cereus, B. megaterium, and S. pneumoniae).
These results underscore the potent antibacterial attributes of Asteraceae species. In order to
fully harness their therapeutic potential, future investigations could delve into identifying the
specific molecules responsible for these activities.

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Potential Probiotic Bacillus Strains Isolated from Contaminated Soil in North Macedonia: Salmonella Growth Inhibition

Salmonellosis, which occurs most frequently (85%) as a result of consuming contaminated food, is brought on by salmonellae, which are bacteria that can infect both humans and animals. By assisting with the absorption of some critical nutrients, probiotics have the potential to exert growth-promoting effects by competitively excluding pathogens and boosting feed conversion rates. In the prevention and treatment of Salmonella illnesses, probiotics are seen as an alternative to antibiotics. To utilize probiotica as previously suggested, it is necessary to thoroughly assess their features and choose the bacteria that will work best for the intended purpose. The aim of this study was to investigate the probiotic properties of three Bacillus spp. strains isolated from contaminated soil in North Macedonia and their antimicrobial activity against Salmonella enterica ATCC 10708 using the agar-well diffusion method. For identification, isolates were characterized morphologically and biochemically. Additionally, their ability to survive in the presence of bile salts and at low pH, high osmotic concentrations of NaCl and their susceptibility to antibiotics were examined. The capacity of isolates to metabolize various sources of carbohydrates was also assessed. Each tested strain demonstrated antagonistic activity against Salmonella enterica ATCC 10708. The three different Bacillus strains were all resilient to an acidic environment (pH 3.0) and a high osmotic pressure (NaCl at 6.5%). This research indicates that new Bacillus strains' probiotic qualities are also promising and exhibit strong inhibition activity against Salmonella enterica ATCC 10708.

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Evaluation of the effects of food safety training on the microbiological load present in equipment’s, surfaces, utensils, and food manipulator`s hands in restaurants
Published: 30 November 2023 by MDPI in The 2nd International Electronic Conference on Microbiology session Poster Session

Restaurants are a place were a lot of people go to have a delicious meal and have a good time however it’s in the hands of the restaurant staff to proportionate that good environment and ensure the tasty meals are microbiologically safe. Food training comes a long way in this regard to help give that quality to the consumer but there is a lot of restaurants that the workers don’t have the proper training for handling food or to keep the establishment food safe. This study was aimed to proportionate the knowledge of food safety and to help the workers follow the right path. It was evaluated if the training given to the food manipulators was helpful and had a significant impact in reducing the load of microbiological contamination present during the work.

For the present work were carried out four moments of analyses at four restaurants, two moments analyses were done before food safety training and the other two were done after food safety training. In each visit, thirty-two swabs were performed from the equipment’s, surfaces, and utensils all together and eight swabs were performed of four manipulators (right and left hand). Also, we evaluated the presence of Listeria monocytogenes in drains using absorbent sponges. This study analysed mesophilic microorganisms in Plate Count Agar® (PCA), Enterobacteriaceae in Violet Red Bile Glucose Agar® (VRBG), Escherichia coli in Tryptone Bile X-Glucuronide Agar® (TBX), Staphylococcus aureus in Baird Park Agar® (BP) and Listeria monocytogenes in Chromagar Listeria and enrichment medium Fraser I and Fraser II. The results were analysed based on the microbial criteria of Pablo., B. Moragas, M. (2013) K. Soares et al. (2019) and Labović et al. (2023)

It was evaluated global hygienic conditions among the four restaurants. Of the 208 swabs performed, before food safety training, to equipment’s, surfaces, and utensils, 15% of the results for Enterobacteriaceae and 26% of the results for mesophilic microorganisms weren’t compliant with the hygienic safety limits and for the 64 swabs done to the hands of the food manipulators 31% of the Enterobacteriaceae and 64% of the mesophilic values were well above the safe limits. In this study we also searched for the presence of Listeria monocytogenes in the drains of 4 restaurants turning out 25% of the analysis to be positive. After the training the presence of Listeria monocytogenes on the drains was absent. Using Statistica software we determined the existence of significative positive differences when comparing the analysis before training and after training with p-values below 0.05. On average across the 4 restaurants there was a reduction of more than 90% of the load of microorganisms like Enterobacteriaceae and Mesophilic microorganisms on the surfaces referred above and on the manipulator’s hands.

With these results we can conclude that food safety training is vital in the food industry, mainly, in catering units. There is always something new that the food handlers can learn, and it can have a huge impact in serving meals with a better quality and safety.

Acknowledgments: This work was supported by National Funds from FCT - Portuguese Foundation for Science and Technology, under the projects UIDB/CVT/00772/202, and LA/P/0059/2020 and UIDB/04033/2020.

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Human pathogenic free-living amoebas in faeces from cows and pigs from Bombali and Tonkolili Districts, Sierra Leone

Human pathogenic free-living amoebae (FLA), specifically Acanthamoeba spp., Balamuthia mandrillaris and Naegleria fowleri, are rarely studied in animals’ gastrointestinal (GI) tract or their faeces as they do not have an obligate parasitic life cycle. However, FLA from different taxa have been recently recovered and identified in pigs’ GI tract and their faeces, suggesting a potential transmission source for pathogenic FLA and their associated intracellular bacteria. The main aim was to determine the presence of these three specific FLA species in faeces from cows and pigs monitored across Bombali and Tonkolili Districts, Sierra Leone (West Africa). Fresh faecal samples were aseptically collected, either from recent deposition or during defecation, from 12 pigs and 8 cows in Spring 2019. Samples were individually packed in plastic containers and immediately stored in a -80 °C freezer. Fourteen samples were collected from five locations across Makeni city (Bombali District): animal market (5 cows, 1 pig), general and pig slaughterhouses (5 pigs), Lorrey Park (2 cows) and Comforti (1 cow). Additionally, 6 pigs were monitored in Royanka, within the Tonkolili District. DNA was extracted from appropriately pre-concentrated faecal samples using FastDNA® Spin Kit. PCR inhibitors were removed using the QIAamp® micro DNA extraction kit. Extracts were screened for FLA using a triplex real-time TaqMan PCR assay which simultaneously identifies these three human pathogenic amoebae. Positive controls were used for each amoeba. All samples screened were negative. However, our results should be considered as inconclusive, owing to the limited number of animals and specific FLA species monitored. Moreover, we detected Acanthamoeba spp. in water reservoirs (wells and ponds) used for drinking by those animals from which samples were collected/screened. We also detected B. mandrillaris in the river in Royanka, which would confirm the presence of this emerging FLA in Tonkolili District, being the first time reported in the literature. In addition, the pre-concentration technique used might have not facilitated the detection of these FLA species, especially if they have a very low presence, as other recovery methods (e.g. filtration, sedimentation) have been described as more appropriate for recovering and culturing free-living protozoa from porcine faeces. Further monitoring studies, which also include non-pathogenic FLA taxa, would be required to understand the presence/circulation of these pathogenic/opportunistic species, particularly Acanthamoeba spp., in farm animals across these Sierra Leonean districts, to control the presence of foodborne pathogens.

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Assay development for phagocytosis activity evaluation
Published: 30 November 2023 by MDPI in The 2nd International Electronic Conference on Microbiology session Poster Session

The increased risk of developing age-related diseases in the elderly is associated with an imbalance and deficiency of the immune response, therefore, specific treatment and vaccination approaches should be developed. The efficiency of phagocytic activity is a significant organism's indicator which decreases with the aging of the immune system. The medications are able to influence phagocytosis, having a blocking or activating effect, are important modulators of immune function. We are developing an ex vivo assay indispensable for medication screening in human and Macaca fascicularis whole blood. M.fascicularis is the well-recognized preclinical model having human-like immune responses. This assay is suitable for routine phagocytosis quantification experiments, including distinguishing between particles adhering to the cell surface and ingested particles. For assay verification several published control drugs were successfully used for blocking and acceleration of phagocytosis. Besides, this test is combined with another activity type such as ROS assay and antibody staining. Ongoing experiments evaluating human and animal phagocytosis indices at different ages will provide statistical standards to be used for medication preclinical and clinical trials. This assay assists to find medications for enhancing the immune response and antigen presentation in the elderly. Moreover, screening of medications, having impact to phagocytosis and further researches of their mechanisms may bring us closer to the comprehension of fundamental process of immune system aging and to provide a perspective for immune response correction.

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Unraveling phylogenetic relationships through A. carbonarius and A. tubingensis sequence analyses

The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. In this work, we report a clarification of the phylogenetic relationship between A. carbonarius and A. tubingensis by the screening of ITS-5.8RDNA, (niiA-niaD), ß-tubulin and EF-1 genes. Phylogenetic analysis of aspergilli ITS-5.8rDNA sequences divided A. carbonarius and A. tubingensis into two coherent clusters and showed a close intergeneric relationship which is in keeping with the existing morphological and taxonomic classification. Herein, A. carbonarius exhibit a complete similarity (100%) for the three target genes: intergenic region of (niiA-niaD), ß-tubulin and EF-1. Tree resulting from a bootstrap analysis indicate branch points when the significance is 98% minimum for each gene (ß-tubulin and EF-1). The phylogenetic analysis of aspergilli genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. carbonarius and A. tubingensis. This is the first work describing evolutionary relationship between both species. At the same time, this finding can be one of the natural processes in the course of evolution of new taxa.

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Enhanced Biohydrogen Production from Food Waste via Separate Hydrolysis and Fermentation: A Sustainable Approach

Biohydrogen production from renewable resources holds promise for sustainable energy generation. This study explores the potential of utilizing food waste, a prevalent global environmental issue, as a substrate for efficient biohydrogen production. Two predominant biological methods, dark fermentation and photosynthesis, were evaluated for their feasibility in harnessing carbohydrates from food waste. Dark fermentation emerged as a more practical option due to its lower energy requirements and absence of light limitations.

The utilization of food waste as a substrate for biohydrogen production offers a dual benefit of addressing waste disposal challenges and providing an alternative energy source. With over a billion tons of food waste generated annually, accounting for a substantial portion of global food production, its high starch and protein content makes it an economically attractive source for biofuel production. The complexity lies in breaking down macromolecules, such as starch and protein, into utilizable forms (glucose and free amino nitrogen) through hydrolysis, a rate-limiting step in most bioprocesses.

To overcome the hydrolysis limitation, a separate hydrolysis and fermentation approach is proposed. Pretreatment techniques are employed to optimize the conversion of complex substrates in food waste into nutrient-rich solutions. This approach not only enhances the efficiency of the hydrolysis stage but also promotes overall biohydrogen production rates. The operating conditions during pretreatment can be tailored to maximize the conversion efficiency, thereby mitigating the challenges associated with substrate complexity.

In conclusion, this study highlights the potential of harnessing food waste for biohydrogen production through dark fermentation, providing a dual solution to waste management and renewable energy needs. The proposed separate hydrolysis and fermentation approach offers a practical strategy to optimize nutrient conversion and increase biohydrogen yields. As the world grapples with both environmental and energy challenges, this sustainable approach could play a pivotal role in shaping a more eco-friendly and energy-efficient future.

Acknowledgments: PN23150401 – The cascade valorisation of agro-industrial waste of plant biomass type in bioproducts with added value in the circular bioeconomy system.

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Influence of Pine Volatiles on Growth of an Ophiostomatoid Fungi Associated with Pine wilt Disease in Pinus pinaster

Phytopathogenic ophiostomatoid fungi are known to have symbiotic associations with conifer bark beetles. Many of these symbiotic fungi improve insect survival by damaging the host conifer’s defences and providing essential nutrients. Ophiostomatoid fungi develop in the insect’s galleries and grow into the transport vessels of the host, causing a dark blue discoloration of the wood (sap stain) and contributing to the degradation of the host tree. This fungal group takes an important role on pine wilt disease (PWD), caused by the pinewood nematode (PWN), since they begin proliferating once the pine hosts decay, and can serve as nutrition to the PWN after the host is dead. Recently, the community of ophiostomatoid fungi associated to Pinus pinaster with PWD in the field was cultured and profiled. To understand if volatiles commonly emitted by pines intervene on fungal growth, the present work analysed the influence of α-pinene, β-pinene and trans-β-caryophyllene on one of these isolates.

The volatiles analysed appeared to promote fungal growth in the first 24h, but lost this effect after 48 or 72 h, probably due to compound volatilization. After 5 days, fungal growth in contact with the compounds was similar to control cultures, with the exception of α-pinene where growth appeared to be slightly lower. Profiling the influence of volatile organic compounds on the PWD complex can contribute to a better understanding of the chemical communication occurring between its different intervenients.

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