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1.
Folia Microbiol (Praha) ; 69(3): 521-547, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38480635

RESUMO

Biodiesel is a type of sustainable, biodegradable energy made from natural sources like vegetable oils, animal fat, and from microbes. Unlike traditional diesel, it has a lower carbon footprint and produces fewer harmful emissions when burned. Biodiesel has gained popularity as a more sustainable substitute for hydrocarbon-based diesel and may be utilized in diesel engines without any modification. In this review, biodiesel from microorganisms such as algae, yeast, and fungi and advantages over another feedstock were discussed. The life cycle evaluation of biodiesel is a thorough assessment of the ecological and economic effects of biodiesel production and use, from the extraction of raw ingredients to the waste disposal process. The life cycle analysis considers the entire process, including the production of feedstocks, the production of biodiesel, and the use of biodiesel in vehicles and other applications. Life cycle analysis of biodiesel produced from microorganisms takes into consideration the environmental impact and sustainability of each step in the production process, including the impact on land use, water use, greenhouse gas emissions, and the availability of resources. In this section, biodiesel produced from microorganisms and other raw materials, its comparisons, and also steps involved in the life cycle such as the cultivation of microorganisms, harvesting of biomass, and conversion to biodiesel were discussed. The processes like extraction and purification, hydrothermal liquefaction, and their environmental impacts were examined by using various LCA software from the previously mentioned process.


Assuntos
Biocombustíveis , Fungos , Biocombustíveis/microbiologia , Fungos/isolamento & purificação , Fungos/classificação , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Biomassa
2.
Bioprocess Biosyst Eng ; 46(12): 1729-1754, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37743409

RESUMO

This review aimed to show that bioherbicides are possible in organic agriculture as natural compounds from fungi and metabolites produced by them. It is discussed that new formulations must be developed to improve field stability and enable the commercialization of microbial herbicides. Due to these bottlenecks, it is crucial to advance the bioprocesses behind the formulation and fermentation of bio-based herbicides, scaling up, strategies for field application, and the potential of bioherbicides in the global market. In this sense, it proposed insights for modern agriculture based on sustainable development and circular economy, precisely the formulation, scale-up, and field application of microbial bioherbicides.


Assuntos
Herbicidas , Herbicidas/farmacologia , Herbicidas/metabolismo , Fungos/metabolismo , Fermentação , Agricultura
3.
J Environ Manage ; 343: 118141, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37245305

RESUMO

A simple scalable method has been developed to obtain protein hydrolysate from fleshing waste generated during leather processing. UV-Vis, FTIR and Solid State C13 NMR analyses identified that prepared protein hydrolysate is basically collagen hydrolysate. DLS and MALDI-TOF-MS spectra indicated that the prepared protein hydrolysate is mostly comprised of di- and tri-peptides and less poly-dispersed than the standard commercial product. A combination of 0.3% Yeast extract, 1% Protein Hydrolysate (PHz) and 2% Glucose is found to be the most efficient nutrient composition for the fermentative growth of three well-known chitosan producing zygomycetes group of fungi. Mucor sp. showed highest yield of biomass (2.74 g/L) as well as chitosan (335 mg/L). Biomass and chitosan yield for Rhizopus oryzae were found 1.53 g/L; 239 mg/L. Same for Absidia coerulea were 2.05 g/L and 212 mg/L, respectively. This work shows promising prospect of utilization of fleshing waste of leather processing for the low-cost production of industrially important biopolymer chitosan.


Assuntos
Quitosana , Quitosana/química , Quitosana/metabolismo , Hidrolisados de Proteína/metabolismo , Polímeros/metabolismo , Fungos/metabolismo , Fermentação
4.
J Basic Microbiol ; 63(7): 690-708, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36998101

RESUMO

Medicinal plants are an important source of bioactive compounds and have been used to isolate various bioactive compounds having industrial applications. The demand for plants derived bioactive molecules is increasing gradually. However, the extensive use of these plants to extract bioactive molecules has threatened many plant species. Moreover, extracting bioactive molecules from these plants is laborious, costly, and time-consuming. So, some alternative sources and strategies are urgently needed to produce these bioactive molecules similar to that of plant origin. However, the interest in new bioactive molecules has recently shifted from plants to endophytic fungi because many fungi produce bioactive molecules similar to their host plant. Endophytic fungi live in mutualistic association within the healthy plant tissue without causing disease symptoms to the host plant. These fungi are a treasure house of novel bioactive molecules having broad pharmaceutical, industrial, and agricultural applications. The rapid increase in publications in this domain over the last three decades proves that natural product biologists and chemists are paying great attention to the natural bioactive products from endophytic fungi. Though endophytes are source of novel bioactive molecules but there is need of advanced technologies like clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR-Cas9) and epigenetic modifiers to enhance the production of compounds having industrial applications. This review provides an overview of the various industrial applications of bioactive molecules produced by endophytic fungi and the rationale behind selecting specific plants for fungal endophyte isolation. Overall, this study presents the current state of knowledge and highlights the potential of endophytic fungi for developing alternative therapies for drug-resistant infections.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Endófitos/metabolismo , Fungos/metabolismo , Plantas/microbiologia , Simbiose , Anti-Infecciosos/metabolismo , Indústria Farmacêutica , Produtos Biológicos/metabolismo
5.
Food Res Int ; 164: 112318, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737911

RESUMO

Filamentous fungi serve as potential candidates in the production of different value-added products. In the context of food, there are several advantages of using filamentous fungi for food. Among the main advantages is that the fungal biomass used food not only meets basic nutritional requirements but that it is also rich in protein, low in fat, and free of cholesterol. This speaks to the potential of filamentous fungi in the production of food that can substitute animal-derived protein sources such as meat. Moreover, life-cycle analyses and techno-economic analyses reveal that fungal proteins perform better than animal-derived proteins in terms of land use efficiency as well as global warming. The present article provides an overview of the potential of filamentous fungi as a source of food and food supplements. The commercialization potential as well as social, legal and safety issues of fungi-based food products are discussed.


Assuntos
Dieta Vegana , Fungos , Animais , Humanos , Suplementos Nutricionais , Proteínas Fúngicas/metabolismo , Fungos/metabolismo , Aquecimento Global
6.
Mol Psychiatry ; 27(2): 1205-1216, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728799

RESUMO

Evidence suggests that complex interactions between the immune system and brain have important etiological and therapeutic implications in schizophrenia. However, the detailed cellular and molecular basis of immune dysfunction in schizophrenia remains poorly characterized. To better understand the immune changes and molecular pathways, we systemically compared the cytokine responses of peripheral blood mononuclear cells (PBMCs) derived from patients with schizophrenia and controls against bacterial, fungal, and purified microbial ligands, and identified aberrant cytokine response patterns to various pathogens, as well as reduced cytokine production after stimulation with muramyl dipeptide (MDP) in schizophrenia. Subsequently, we performed single-cell RNA sequencing on unstimulated and stimulated PBMCs from patients and controls and revealed widespread suppression of antiviral and inflammatory programs as well as impaired chemokine/cytokine-receptor interaction networks in various immune cell subpopulations of schizophrenic patients after MDP stimulation. Moreover, serum MDP levels were elevated in these patients and correlated with the course of the disease, suggesting increased bacterial translocation along with disease progression. In vitro assays revealed that MDP pretreatment altered the functional response of normal PBMCs to its re-stimulation, which partially recapitulated the impaired immune function in schizophrenia. In conclusion, we delineated the molecular and cellular landscape of impaired immune function in schizophrenia, and proposed a mutual interplay between innate immune impairment, reduced pathogen clearance, increased MDP translocation along schizophrenia development, and blunted innate immune response. These findings provide new insights into the pathogenic mechanisms that drive systemic immune activation, neuroinflammation, and brain abnormalities in schizophrenia.


Assuntos
Citocinas , Esquizofrenia , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacologia , Bactérias/metabolismo , Citocinas/metabolismo , Fungos/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Esquizofrenia/metabolismo
7.
Int J Biol Macromol ; 187: 422-440, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34324901

RESUMO

Developing renewable resource-based plastics with complete biodegradability and a minimal carbon footprint can open new opportunities to effectively manage the end-of-life plastics waste and achieve a low carbon society. Polyhydroxyalkanoates (PHAs) are biobased and biodegradable thermoplastic polyesters that accumulate in microorganisms (e.g., bacterial, microalgal, and fungal species) as insoluble and inert intracellular inclusion. The PHAs recovery from microorganisms, which typically involves cell lysis, extraction, and purification, provides high molecular weight and purified polyesters that can be compounded and processed using conventional plastics converting equipment. The physio-chemical, thermal, and mechanical properties of the PHAs are comparable to traditional synthetic polymers such as polypropylene and polyethylene. As a result, it has attracted substantial applications interest in packaging, personal care, coatings, agricultural and biomedical uses. However, PHAs have certain performance limitations (e.g. slow crystallization), and substantially more expensive than many other polymers. As such, more research and development is required to enable them for extensive use. This review provides a critical review of the recent progress achieved in PHAs production using different microorganisms, downstream processing, material properties, processing avenues, recycling, aerobic and anaerobic biodegradation, and applications.


Assuntos
Bactérias/metabolismo , Plásticos Biodegradáveis/química , Fungos/metabolismo , Microbiologia Industrial , Microalgas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Poli-Hidroxialcanoatos/química , Bactérias/genética , Plásticos Biodegradáveis/economia , Plásticos Biodegradáveis/isolamento & purificação , Reatores Biológicos , Análise Custo-Benefício , Metabolismo Energético , Fungos/genética , Microbiologia Industrial/economia , Microalgas/genética , Plantas Geneticamente Modificadas/genética , Poli-Hidroxialcanoatos/economia , Poli-Hidroxialcanoatos/isolamento & purificação
8.
Toxins (Basel) ; 13(4)2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921591

RESUMO

Zearalenone (ZEA) is a harmful secondary fungal metabolite, produced primarily by plant pathogenic fungi mostly belonging to the genus Fusarium. It is involved in reproductive disorders in animals since its structure is similar to the estrogen hormone. This induces precocious pubertal changes, fertility problems, and hyper estrogenic disorders. The main objectives of this study were to evaluate the ZEA removal capacity of plant-derived lactic acid bacteria (LAB) and to investigate the possible components and mechanisms involved in the removal of ZEA by physically and chemically treated plant-derived LAB. The bacterial cells were characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), and the analysis of zeta potential, and hydrophobic index. Results revealed that 17 out of 33 plant-derived LAB exhibited ZEA removal from liquid medium. The percentage of removal ranged from 0.5-23% and Lactobacillus plantarum BCC 47723, isolated from wild spider flower pickle (Pag-sian-dorng), exhibited the highest removal. The alteration of proteins on L. plantarum BCC 47723 structure by Sodium dodecyl sulphate (SDS) treatment was positively affected on ZEA removal, whereas that of lipids on ZEA removal was negatively observed. Heat treatment influenced the higher ZEA adsorption. SEM images showed that the morphologies of modified bacterial cells were distinctly deformed and damaged when compared with untreated control. FTIR analysis indicated that the original functional groups, which included amide (C=O, C-N), carboxyl (C=O, C-O, O-H), methylene (C=C), and alcohol (O-H) groups, were not changed after ZEA adsorption. The zeta potential indicated that electrostatic interaction was not involved in the ZEA removal, while hydrophobicity was the main force to interact with ZEA. These findings can conclude that adsorption by hydrophobicity is the main mechanism for ZEA removal of plant-derived L. plantarum BCC 47723. The alteration of bacterial cell structure by heat treatment enhanced the efficiency of L. plantarum BCC 47723 for ZEA reduction. Its activity can be protected by the freeze-drying technique. Hence, plant-derived L. plantarum BCC 47723 can be considered as an organic adsorbent for ZEA reduction in food and feedstuff.


Assuntos
Agentes de Controle Biológico/metabolismo , Fungos/metabolismo , Lactobacillus plantarum/metabolismo , Plantas/microbiologia , Zearalenona/metabolismo , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Lactobacillus plantarum/isolamento & purificação , Metabolismo Secundário
9.
Microb Cell Fact ; 20(1): 59, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658027

RESUMO

BACKGROUND: Oleaginous filamentous fungi can accumulate large amount of cellular lipids and potentially serve as a major source of oleochemicals for food, feed, chemical, pharmaceutical, and transport industries. Transesterification of microbial oils is an essential step in microbial lipid production at both laboratory and industrial scale. Direct transesterification can considerably reduce costs, increase sample throughput and improve lipid yields (in particular fatty acid methyl esters, FAMEs). There is a need for the assessment of the direct transesterification methods on a biomass of filamentous fungi due to their unique properties, specifically resilient cell wall and wide range of lipid content and composition. In this study we have evaluated and optimised three common direct transesterification methods and assessed their suitability for processing of fungal biomass. RESULTS: The methods, based on hydrochloric acid (Lewis method), sulphuric acid (Wahlen method), and acetyl chloride (Lepage method), were evaluated on six different strains of Mucoromycota fungi by using different internal standards for gas chromatography measurements. Moreover, Fourier transform infrared (FTIR) spectroscopy was used for the detection of residual lipids in the biomass after the transesterification reaction/extraction, while transesterification efficiency was evaluated by nuclear magnetic resonance spectroscopy. The results show that the majority of lipids, in particular triglycerides, were extracted for all methods, though several methods had substandard transesterification yields. Lewis method, optimised with respect to solvent to co-solvent ratio and reaction time, as well as Lepage method, offer precise estimate of FAME-based lipids in fungal biomass. CONCLUSIONS: The results show that Lepage and Lewis methods are suitable for lipid analysis of oleaginous filamentous fungi. The significant difference in lipid yields results, obtained by optimised and standard Lewis methods, indicates that some of the previously reported lipid yields for oleaginous filamentous fungi must be corrected upwards. The study demonstrates value of biomass monitoring by FTIR, importance of optimal solvent to co-solvent ratio, as well as careful selection and implementation of internal standards for gas chromatography.


Assuntos
Fungos/química , Lipídeos/análise , Biomassa , Cromatografia Gasosa , Esterificação , Fungos/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Triglicerídeos/análise
10.
Toxins (Basel) ; 13(2)2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535530

RESUMO

The extensive exposure to multiple mycotoxins has been demonstrated in many countries; however, realistic assessments of the risks related to cumulative exposure are limited. This biomonitoring study was conducted to investigate exposure to 23 mycotoxins/metabolites and their determinants in 227 adults (aged 20-88 years) in the Yangtze River Delta, China. Eight mycotoxins were detected in 110 urine samples, and multiple mycotoxins co-occurred in 51/227 (22.47%) of urine samples, with deoxynivalenol (DON), fumonisin B1 (FB1), and zearalenone (ZEN) being the most frequently occurring. For single mycotoxin risk assessment, FB1, ZEN, aflatoxin B1 (AFB1), and ochratoxin A (OTA) all showed potential adverse effects. However, for the 12 samples containing DON and ZEN, in which none had a hazard risk, the combination of both mycotoxins in two samples was considered to pose potential endocrine disrupting risks to humans by hazard index (HI) method. The combined margin of exposure (MOET) for AFB1 and FB1 could constitute a potential health concern, and AFB1 was the main contributor. Our approach provides a blueprint for evaluating the cumulative risks related to different types of mycotoxins and opens a new horizon for the accurate interpretation of epidemiological health outcomes related to multi-mycotoxin exposure.


Assuntos
Monitoramento Biológico , Fungos/metabolismo , Micotoxinas/urina , Rios/microbiologia , Microbiologia da Água , Adulto , Idoso , Idoso de 80 Anos ou mais , Carga Corporal (Radioterapia) , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micotoxinas/efeitos adversos , Medição de Risco , Urinálise , Adulto Jovem
11.
J Appl Microbiol ; 130(2): 356-369, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32681565

RESUMO

AIMS: To investigate the microbiological and nutritional quality of liquid finisher pig feed on commercial production units and the factors influencing this. METHODS AND RESULTS: Microbiological and physio-chemical analyses were performed on liquid feed sampled from the mixing tank and troughs of the finisher section of eight commercial pig units. Lactic acid bacteria, yeast and Escherichia coli counts, as well as lactic acid, ethanol and acetate concentrations were higher in residual feed sampled from the troughs compared with mixing tank samples (P < 0·001). Feed pH, as well as lysine, methionine and threonine concentrations and gross energy were all lower in the residual trough samples (P < 0·001). Liquid co-products reduced E. coli counts in the residual trough samples (P < 0·05), pH in the mixing tank (P < 0·01) and fresh trough samples (P < 0·05) and mould counts at all three sampling locations (P < 0·01) but sanitation practices had no impact. CONCLUSIONS: Even when considered unfermented, a considerable degree of spontaneous fermentation occurs in liquid feed, with resultant negative effects on nutritional quality. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of the first studies showing that uncontrolled fermentation of fresh liquid pig feed is commonplace on commercial units, highlighting the need for implementation of suitable control strategies.


Assuntos
Ração Animal/microbiologia , Microbiologia de Alimentos , Ração Animal/análise , Animais , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Fermentação , Fungos/isolamento & purificação , Fungos/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Suínos , Leveduras/isolamento & purificação , Leveduras/metabolismo
12.
J Sci Food Agric ; 101(5): 1812-1821, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32893877

RESUMO

BACKGROUND: Corn, a main feed ingredient in the livestock industry, is one of the most susceptible crops to fungal infection and aflatoxin contamination. Livestock feeding on aflatoxin (AF)-contaminated feed have been shown to experience feed refusal, and decreased growth rate, milk production, and feed efficiency. In poultry, AF poisoning causes weight loss, poor feed efficiency, and reduced egg production and egg weight. The present work therefore aimed to determine the prevalence of mycotoxigenic fungi and the occurrence of AF contamination along the integrated corn-based poultry feed supply chain in Malaysia. A total of 51 samples were collected from different points along the feed supply chain from integrated poultry feed companies. The samples were subjected to mycological analyses (fungal isolation, enumeration, identification), and AFs were quantified by high-performance liquid chromatography equipped with a fluorescence detector (HPLC-FLD). RESULTS: Samples collected from sampling point 1 (company A) and sampling point 9 (company B) yielded the highest total fungal load (>log 4 CFU g-1 ). The prevalent fungal genera isolated were Aspergillus, Fusarium, and Penicillium spp. Aflatoxin B1 was detected in 8.3% of corn samples, and 7.4% of corn-based poultry feed samples along the feed supply chain, whereas AFs B2 , G1 , and G2 were not detected. CONCLUSION: The incidence of mycotoxigenic fungi along the integrated poultry feed supply chain warrant continuous monitoring of mycotoxin contamination to reduce the exposure risk of mycotoxin intake in poultry. © 2020 Society of Chemical Industry.


Assuntos
Aflatoxinas/análise , Ração Animal/microbiologia , Contaminação de Alimentos/análise , Aves Domésticas/metabolismo , Zea mays/química , Aflatoxinas/metabolismo , Ração Animal/análise , Animais , Cromatografia Líquida de Alta Pressão , Abastecimento de Alimentos/estatística & dados numéricos , Fungos/classificação , Fungos/isolamento & purificação , Fungos/metabolismo , Malásia , Zea mays/microbiologia
13.
Toxins (Basel) ; 12(10)2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33049980

RESUMO

Mycotoxigenic fungi and their toxins are a global concern, causing huge economic and health impacts in developing countries such as Ethiopia, where the mycotoxin control system is inadequate. This work aimed to review the occurrences of agriculturally essential fungi such as Aspergillus, Fusarium, and Penicillium and their major mycotoxins in Ethiopian food/feedstuffs. The incidents of crucial toxins, including aflatoxins (B1, B2, G1, G2, M1), fumonisins (B1, B2), zearalenone, deoxynivalenol, and ochratoxin A, were studied. The impacts of chronic aflatoxin exposure on liver cancer risks, synergy with chronic hepatitis B infection, and possible links with Ethiopian childhood malnutrition were thoroughly examined. In addition, health risks of other potential mycotoxin exposure are also discussed, and the impacts of unsafe level of mycotoxin contaminations on economically essential export products and livestock productions were assessed. Feasible mycotoxin mitigation strategies such as biocontrol methods and binding agents (bentonite) were recommended because they are relatively cheap for low-income farmers and widely available in Ethiopia, respectively. Moreover, Ethiopian mycotoxin regulations, storage practice, adulteration practice, mycotoxin tests, and knowledge gaps among value chain actors were highlighted. Finally, sustained public awareness was suggested, along with technical and human capacity developments in the food control sector.


Assuntos
Produtos Agrícolas/microbiologia , Países em Desenvolvimento , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Fungos/metabolismo , Gado/microbiologia , Micotoxinas/efeitos adversos , Saúde Pública , Animais , Produtos Agrícolas/economia , Países em Desenvolvimento/economia , Etiópia/epidemiologia , Cadeia Alimentar , Microbiologia de Alimentos/economia , Inocuidade dos Alimentos , Armazenamento de Alimentos , Doenças Transmitidas por Alimentos/economia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Fungos/crescimento & desenvolvimento , Humanos , Micotoxinas/metabolismo , Prevalência , Saúde Pública/economia , Medição de Risco
14.
Toxins (Basel) ; 12(9)2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32872457

RESUMO

In this paper, a study of fungal and multi-mycotoxin contamination in 140 Camellia sinensis and 26 herbal teas marketed in Latvia is discussed. The analysis was performed using two-dimensional liquid chromatography with time-of-flight mass spectrometry (2D-LC-TOF-MS) and MALDI-TOF-MS. In total, 87% of the tea samples tested positive for 32 fungal species belonging to 17 genera, with the total enumeration of moulds ranging between 1.00 × 101 and 9.00 × 104 CFU g-1. Moreover, 42% of the teas (n = 70) were contaminated by 1 to 16 mycotoxins, and 37% of these samples were positive for aflatoxins at concentrations ranging between 0.22 and 41.7 µg kg-1. Deoxynivalenol (DON) and its derivatives co-occurred in 63% of the tea samples, with their summary concentrations reaching 81.1 to 17,360 µg kg-1. Ochratoxin A (OTA), enniatins, and two Alternaria toxins were found in 10-37% of the teas at low concentrations. The dietary exposure assessment based on the assumption of a probable full transfer of determined mycotoxins into infusions indicated that the analysed teas are safe for consumers: the probable maximum daily exposure levels to OTA and the combined DON mycotoxins were only 0.88 to 2.05% and 2.50 to 78.9% of the tolerable daily intake levels.


Assuntos
Camellia sinensis/microbiologia , Exposição Dietética , Fungos/metabolismo , Micotoxinas/análise , Chá/microbiologia , Chás de Ervas/microbiologia , Cromatografia Líquida , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Exposição Dietética/efeitos adversos , Humanos , Letônia , Micotoxinas/efeitos adversos , Medição de Risco , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Microbiologyopen ; 9(6): 1067-1084, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32352657

RESUMO

The study performed on the stone materials from the Convent of Christ revealed the presence of a complex microbial ecosystem, emphasizing the determinant role of microorganisms on the biodecay of this built cultural heritage. In this case study, the presence of Rubrobacter sp., Arthrobacter sp., Roseomonas sp., and Marinobacter sp. seems to be responsible for colored stains and biofilm formation while Ulocladium sp., Cladosporium sp., and Dirina sp. may be related to structural damages. The implementation of high-throughput sequencing approaches on the Convent of Christ's biodecay assessment allowed us to explore, compare, and characterize the microbial communities, overcoming the limitations of culture-dependent techniques, which only identify the cultivable population. The application of these different tools and insights gave us a panoramic view of the microbiota thriving on the Convent of Christ and signalize the main biodeteriogenic agents acting on the biodecay of stone materials. This finding highlighted the importance of performing metagenomic studies due to the improvements and the reduced amount of sample DNA needed, promoting a deeper and more detailed knowledge of the microbiota present on these dynamic repositories that support microbial life. This will further enable us to perform prospective studies in quarry and applied stone context, monitoring biogenic and nonbiogenic agents, and also to define long-term mitigation strategies to prevent biodegradation/biodeterioration processes.


Assuntos
Bactérias/classificação , Biodegradação Ambiental , Fungos/classificação , Sedimentos Geológicos/microbiologia , Microbiota/genética , Arqueologia , Bactérias/genética , Bactérias/metabolismo , DNA Bacteriano/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Ecossistema , Fungos/genética , Fungos/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Portugal
16.
PLoS One ; 15(4): e0229921, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330147

RESUMO

Melanized fungi have been shown to thrive in environments with high radionuclide concentrations, which led to the association of the pigment melanin with the protection against ionizing radiation. Several hypotheses regarding the function of melanin have been proposed. Yet, the exact mechanism behind the protective property of melanin is unclear and poorly explored. A better understanding of the mechanisms that are involved in increasing the tolerance of the organisms to ionizing radiation could lead to technology transfer to human-related applications. Effective protection from radiation is essential for human space flight in general and human missions beyond Low Earth Orbit specifically. In this paper, we follow a biomimetic approach: we test two of current hypotheses and discuss how they could be applied to radiation shield designs. First we focus on the interaction of melanin with high energy electrons, which has been suspected to reduce the kinetic energy of the electrons through a cascade of collisions, thus providing physical shielding. Second, we investigate if the spatial arrangement of melanin, organized as a thin film or a collection of hollow micro-spheres, affects its shielding properties. To this end, we measured experimentally and by numerical simulations the attenuation of ß-radiation as pass through solutions and suspensions of melanin and contrasted the values to the ones of cellulose, a substance with similar elemental composition. Further, we investigate the spatial arrangement hypothesis using Monte Carlo simulations. In agreement with the simulations, our experiments indicated that melanin does not provide improved shielding in comparison to cellulose from ß-radiation. However, our simulations suggest a substantial effect of the spatial arrangement on the shielding performance of melanin, a pathway that could be transferred to the design of composite radiation shields.


Assuntos
Ciências da Terra , Fungos/metabolismo , Melaninas/metabolismo , Radiação Ionizante , Biomimética , Fungos/química , Humanos , Melaninas/química , Melaninas/efeitos da radiação , Método de Monte Carlo , Voo Espacial
17.
Toxins (Basel) ; 12(4)2020 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-32290581

RESUMO

Ochratoxin A (OTA) is produced by fungi present in several agricultural products with much relevance to food safety. Since this mycotoxin is widely found in cereals, beer has a potential contamination risk. Therefore, it was deemed essential to quantify, for the first time, the levels of OTA in beer, a cereal-based product that is marketed in Portugal, as well as to calculate the human estimated weekly intake (EWI) and risk assessment. A total of 85 samples were analyzed through immunoaffinity clean-up, followed by liquid chromatography-fluorescence detection (LC-FD). This analytical methodology allowed a limit of quantification (LOQ) of 0.43 µg/L. The results showed that 10.6% were contaminated at levels ranging between

Assuntos
Cerveja/microbiologia , Publicidade Direta ao Consumidor , Microbiologia de Alimentos , Fungos/metabolismo , Ocratoxinas/análise , Comércio , Qualidade de Produtos para o Consumidor , Humanos , Nível de Efeito Adverso não Observado , Portugal , Medição de Risco
18.
Toxins (Basel) ; 12(4)2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272644

RESUMO

The emergence of commercial fish farming has stimulated the establishment of fish feed factories in Uganda. However, no information is available on the safety of the feed, mainly due to lack of mycotoxin testing facilities and weak regulatory systems. A study was carried out to examine fungal colonization and mycotoxin contamination in fish feed samples (n = 147) of different types collected from nine fish farms (n = 81) and seven fish feed factories (n = 66) in the Lake Victoria Basin (LVB). Fungi were isolated in potato dextrose agar, grouped into morphotypes and representative isolates from each morphotype were identified based on the internal transcribed spacer (ITS) region of ribosomal DNA sequences. Aflatoxin B1 (AFB1) and total fumonisin (combinations of B1, B2 and B3; hereinafter named fumonisin) levels in feed samples were determined by enzyme-linked immunosorbent assay (ELISA). A wide range of fungi, including toxigenic Aspergillus flavus and Fusarium verticillioides, were isolated from the fish feed samples. AFB1 was detected in 48% of the factory samples and in 63% of the farm samples, with toxin levels <40 and >400 µg/kg, respectively. Similarly, 31% of the factory samples and 29% of the farm samples had fumonisin contamination ranging between 0.1 and 4.06 mg/kg. Pellets and powder had higher mycotoxin contamination compared to other commercially available fish feed types. This study shows AFB1 as a potential fish feed safety issue in the LVB and suggests a need for more research on mycotoxin residues in fish fillets.


Assuntos
Aflatoxina B1/análise , Ração Animal/microbiologia , Pesqueiros , Peixes , Microbiologia de Alimentos , Fumonisinas/análise , Fungos/metabolismo , Alimentos Marinhos , Aflatoxina B1/efeitos adversos , Ração Animal/efeitos adversos , Criação de Animais Domésticos , Animais , Fumonisinas/efeitos adversos , Fungos/classificação , Fungos/genética , Lagos , Ribotipagem , Medição de Risco , Uganda
19.
Toxins (Basel) ; 12(3)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120954

RESUMO

Mycotoxins are toxic secondary fungal metabolites that commonly contaminate crops and food by-products and thus, animal feed. Ingestion of mycotoxins can lead to mycotoxicosis in both animals and humans, and at subclinical concentrations may affect animal production and adulterate feed and animal by-products. Mycotoxicity mechanisms of action (MOA) are largely unknown, and co-contamination, which is often the case, raises the likelihood of mycotoxin interactions. Mitigation strategies for reducing the risk of mycotoxicity are diverse and may not necessarily provide protection against all mycotoxins. These factors, as well as the species-specific risk of toxicity, collectively make an assessment of exposure, toxicity, and risk mitigation very challenging and costly; thus, in-vitro cell culture models provide a useful tool for their initial assessment. Since ingestion is the most common route of mycotoxin exposure, the intestinal epithelial barrier comprised of epithelial cells (IECs) and immune cells such as macrophages, represents ground zero where mycotoxins are absorbed, biotransformed, and elicit toxicity. This article aims to review different in-vitro IEC or co-culture models that can be used for assessing mycotoxin exposure, toxicity, and risk mitigation, and their suitability and limitations for the safety assessment of animal foods and food by-products.


Assuntos
Técnicas de Cultura de Células , Mucosa Intestinal/efeitos dos fármacos , Micotoxinas/toxicidade , Animais , Contaminação de Alimentos/prevenção & controle , Fungos/metabolismo , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Modelos Biológicos , Micotoxinas/análise , Micotoxinas/biossíntese , Risco
20.
Nat Chem Biol ; 16(2): 113-121, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31974527

RESUMO

Microbial chemical production is a rapidly growing industry, with much of the growth fueled by advances in synthetic biology. New approaches have enabled rapid strain engineering for the production of various compounds; however, translation to industry is often problematic because native phenotypes of model hosts prevent the design of new low-cost bioprocesses. Here, we argue for a new approach that leverages the native stress-tolerant phenotypes of non-conventional microbes that directly address design challenges from the outset. Growth at high temperature, high salt and solvent concentrations, and low pH can enable cost savings by reducing the energy required for product separation, bioreactor cooling, and maintaining sterile conditions. These phenotypes have the added benefit of allowing for the use of low-cost sugar and water resources. Non-conventional hosts are needed because these phenotypes are polygenic and thus far have proven difficult to recapitulate in the common hosts Escherichia coli and Saccharomyces cerevisiae.


Assuntos
Bactérias/metabolismo , Fungos/metabolismo , Microbiologia Industrial/métodos , Bactérias/genética , Fungos/genética , Engenharia Genética , Concentração de Íons de Hidrogênio , Microbiologia Industrial/economia , Engenharia Metabólica , Microrganismos Geneticamente Modificados/fisiologia , Pressão Osmótica , Fenótipo , Solventes , Estresse Fisiológico
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