RESUMO
The potential biopreservative role of a Type III sourdough (tIII-SD), produced by starter cultures of Fructilactobacillus sanfranciscensis and Lactiplantibacillus plantarum ATCC 8014, was assessed for its antifungal activity in baking applications. Fermentation was carried out using different substrates to enhance the production of antifungal metabolites for 24 and 48 h. The tIII-SD samples were analyzed in relation to pH, total titratable acidity (TTA) and the production of organic acids. The water/salt-soluble extract of the tIII-SD was evaluated in relation to the inhibition potential against key fungi that contaminate bakery products including Penicillium roqueforti, Penicillium chrysogenum and Aspergillus niger. Finally, breads with 10 % of the tIII-SD were prepared and the fungi contamination was evaluated throughout the shelf life period. The lowest pH value in sourdough was obtained from 48-hour fermentation by L. plantarum. The saline extracts exhibited varying degrees of inhibition in the in vitro test; however, the greatest enhancement of this effect was obtained when whole wheat grain flour was used. The tIII-SD crafted from a blend of wheat and flaxseed flours and fermented with F. sanfranciscensis for 48 h (BSWF48h-FS), demonstrated superior performance compared to other formulations. This variant exhibited a total shelf life of 10 days, suggesting that the utilization of tIII-SD could serve as a viable alternative for natural antifungal agents, proving beneficial for the bakery industry.
Assuntos
Antifúngicos , Pão , Fermentação , Microbiologia de Alimentos , Pão/microbiologia , Pão/análise , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Farinha/análise , Conservação de Alimentos/métodos , Triticum/química , Triticum/microbiologia , Penicillium chrysogenum , Lactobacillus plantarum/metabolismoRESUMO
The antibacterial secondary metabolites of the fungus Penicillium chrysogenum associated with the beetle Aspongopus chinensis were investigated through chromatographic fractionation methods of ethyl acetate extracts of the fungal cultures. Five compounds were isolated, and their structures were determined as emodin, 4-(methoxymethyl)benzoic acid, isoochracinic acid, secalonic acid D, and dicerandrol A using mass spectroscopy and nuclear magnetic resonance spectroscopic analyses. Emodin exhibited strong antimicrobial activity, especially against Staphylococcus aureus even when growing on cooked pork, with a minimal inhibitory concentration (MIC) of 6.3 µg/mL. Dimeric tetrahydroxanthones, such as secalonic acid D and dicerandrol A, also exhibited potent activity, with MIC values ranging from 9.5 to 28.5 µg/mL. In summary, P. chrysogenum was isolated as a symbiotic fungus of the beetle A. chinensis for the first time and this strain could generate antibacterial secondary metabolites, which could potently inhibit gram-positive bacteria growth in vitro.
Assuntos
Besouros , Emodina , Penicillium chrysogenum , Penicillium , Animais , Penicillium chrysogenum/química , Antibacterianos , Staphylococcus aureus , Testes de Sensibilidade MicrobianaRESUMO
INTRODUCTION: Fungal infections of the central nervous system present a variety of clinical syndromes, such as meningitis, encephalitis, raised intracranial pressure with a nonspecific presentation, and, in the last two decades, have increased the incidence of these fungal infections. Fungal meningoencephalitis is frequently associated with Cryptococcus, but this report stands out for presenting one species of Penicillium genus. OBJECTIVES: Here, we present the first case of meningoencephalitis associated with brain injury caused by Penicillium chrysogenum, in a patient who is immunocompetent and was admitted to Hospital Naval Marcílio Dias, Rio de Janeiro, Brazil. METHODS: To identify the fungal species, we performed phenotypic and genotypic methodologies, from the culture to the sequencing of internal transcribed spacer region, and ß-tubulin gene, a rare fungus in cerebrospinal fluid cultures, belonging to the genus Penicillium, was identified. CONCLUSION: We highlight the importance of the first report of meningoencephalitis caused by P. chrysogenum in a patient who is immunocompetent, registered in Brazil. We also emphasize the need for further studies to determine an effective treatment with the least possible side effects for patients infected by fungi that are rarely related to the most severe forms of invasive infections.
Assuntos
Meningite , Meningoencefalite , Micoses , Penicillium chrysogenum , Penicillium , Humanos , Penicillium chrysogenum/genética , Brasil/epidemiologia , Meningoencefalite/diagnóstico , Meningoencefalite/tratamento farmacológico , Penicillium/genéticaRESUMO
Climatic change is pointed as one of the major challenges for global food security. Based on current models of climate change, reduction in precipitations and in turn, increase in the soil salinity will be a sharp constraint for crops productivity worldwide. In this context, root fungi appear as a new strategy to improve plant ecophysiological performance and crop yield under abiotic stress. In this study, we evaluated the impact of the two fungal endophytes Penicillium brevicompactum and P. chrysogenum isolated from Antarctic plants on nutrients and Na+ contents, net photosynthesis, water use efficiency, yield and survival in tomato and lettuce, facing salinity stress conditions. Inoculation of plant roots with fungal endophytes resulted in greater fresh and dry biomass production, and an enhanced survival rate under salt conditions. Inoculation of plants with the fungal endophytes was related with a higher up/down-regulation of ion homeostasis by enhanced expression of the NHX1 gene. The two endophytes diminished the effects of salt stress in tomato and lettuce, provoked a higher efficiency in photosynthetic energy production and an improved sequestration of Na+ in vacuoles is suggested by the upregulating of the expression of vacuolar NHX1 Na+/H+ antiporters. Promoting plant-beneficial interactions with root symbionts appears to be an environmentally friendly strategy to mitigate the impact of climate change variables on crop production.
Assuntos
Produtos Agrícolas/metabolismo , Produtos Agrícolas/fisiologia , Endófitos/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Estresse Salino/fisiologia , Sódio/metabolismo , Regiões Antárticas , Biomassa , Mudança Climática , Produtos Agrícolas/microbiologia , Regulação para Baixo/fisiologia , Homeostase/fisiologia , Íons/metabolismo , Lactuca/metabolismo , Lactuca/microbiologia , Lactuca/fisiologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiologia , Solanum lycopersicum/fisiologia , Penicillium chrysogenum/fisiologia , Fotossíntese/fisiologia , Raízes de Plantas/microbiologia , Salinidade , Trocadores de Sódio-Hidrogênio/metabolismo , Solo , Estresse Fisiológico/fisiologia , Taxa de Sobrevida , Regulação para Cima/fisiologia , Água/metabolismoRESUMO
In an earlier work on lovastatin production by Aspergillus terreus, we found that reactive oxygen species (ROS) concentration increased to high levels precisely at the start of the production phase (idiophase) and that these levels were sustained during all idiophase. Moreover, it was shown that ROS regulate lovastatin biosynthesis. ROS regulation has also been reported for aflatoxins. It has been suggested that, due to their antioxidant activity, aflatoxins are regulated and synthesized like a second line of defense against oxidative stress. To study the possible ROS regulation of other industrially important secondary metabolites, we analyzed the relationship between ROS and penicillin biosynthesis by Penicillium chrysogenum and cephalosporin biosynthesis by Acremonium chrysogenum. Results revealed a similar ROS accumulation in idiophase in penicillin and cephalosporin fermentations. Moreover, when intracellular ROS concentrations were decreased by the addition of antioxidants to the cultures, penicillin and cephalosporin production were drastically reduced. When intracellular ROS were increased by the addition of exogenous ROS (H2O2) to the cultures, proportional increments in penicillin and cephalosporin biosyntheses were obtained. It was also shown that lovastatin, penicillin, and cephalosporin are not antioxidants. Taken together, our results provide evidence that ROS regulation is a general mechanism controlling secondary metabolism in fungi.
Assuntos
Acremonium/metabolismo , Cefalosporinas/biossíntese , Penicilinas/biossíntese , Penicillium chrysogenum/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acremonium/efeitos dos fármacos , Vias Biossintéticas , Fermentação , Regulação Fúngica da Expressão Gênica , Peróxido de Hidrogênio/farmacologia , Penicillium chrysogenum/efeitos dos fármacos , Espécies Reativas de Oxigênio/farmacologia , Metabolismo SecundárioRESUMO
Metals are non-biodegradable and recurrent in the environs. Heavy metals tolerant fungiwere isolated from refuse dumpsite soil using pour plate method. These fungiwere identified as Aspergillus niger, Penicillium chrysogenumandRhizomucor sp. The fungal isolates were screened for cadmium (Cd), lead (Pb) and zinc (Zn) with concentration of 200ppm, 400ppm and 600ppm. Aspergillus nigerand Penicillium chrysogenumshowed high tolerance for the metals in contrast to the control. The fungiwith high tolerance were used for biosorption study. However, Penicillium chrysogenumshowed higher lead removal or biosorption potential of 1.07ppm, 3.35ppm and 4.19ppm as compared with Aspergillus nigerwith lead removal of 0.67ppm, 3.11ppm and 3.79ppm at 5th, 10thand 15thday respectively. One-way Analysis of Variance was used to interpret the data generated from the biosorption study which revealed that there was no significant different (p>0.05)between the lead removal of Aspergillus nigerandPenicillium chrysogenumon the 5thday but there was significant difference (p<0.05)in the lead removal of Aspergillus nigerand Penicillium chrysogenumon the 10thand 15thday. This study suggests the use of these fungal isolates for removal and biotreatment of heavy metal contaminated and polluted environment.
Assuntos
Análise do Solo , Fungos/fisiologia , Intoxicação por Chumbo , Resíduos de Alimentos , Aspergillus niger , Penicillium chrysogenum , RhizomucorRESUMO
Commercial interest in plant cell wall degrading enzymes (PCWDE) is motivated by their potential for energy or bioproduct generation that reduced dependency on non-renewable (fossil-derived) feedstock. Therefore, underlying work analysed the Penicillium chrysogenum isolate for PCWDE production by employing different biomass as a carbon source. Among the produced enzymes, three xylanase isoforms were observed in the culture filtrate containing sugarcane bagasse. Xylanase (PcX1) presenting 35â¯kDa molecular mass was purified by gel filtration and anion exchange chromatography. Unfolding was probed and analysed using fluorescence, circular dichroism and enzyme assay methods. Secondary structure contents were estimated by circular dichroism 45% α-helix and 10% ß-sheet, consistent with the 3D structure predicted by homology. PcX1 optimally active at pHâ¯5.0 and 30⯰C, presenting t1/2 19â¯h at 30⯰C and 6â¯h at 40⯰C. Thermodynamic parameters/melting temperature 51.4⯰C confirmed the PcX1 stability at pHâ¯5.0. PcX1 have a higher affinity for oat spelt xylan, KM 1.2â¯mg·mL-1, in comparison to birchwood xylan KM 29.86â¯mg·mL-1, activity was inhibited by Cu+2 and activated by Zn+2. PcX1 exhibited significant tolerance for vanillin, trans-ferulic acid, ρ-coumaric acid, syringaldehyde and 4-hydroxybenzoic acid, activity slightly inhibited (17%) by gallic and tannic acid.
Assuntos
Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Penicillium chrysogenum/enzimologia , Agricultura , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Resíduos de Serviços de Saúde , Estrutura Secundária de Proteína , Desdobramento de ProteínaRESUMO
Background: In this work, the xylanase production by Penicillium chrysogenum F-15 strain was investigated using agroindustrial biomass as substrate. The xylanase was purified, characterized and applied in hemicellulose hydrolysis. Results: The highest xylanase production was obtained when cultivation was carried out with sugar cane bagasse as carbon source, at pH 6.0 and 20°C, under static condition for 8 d. The enzyme was purified by a sequence of ion exchange and size exclusion chromatography, presenting final specific activity of 834.2 U·mg·prot-1. T he molecular mass of the purified enzyme estimated by SDS-PAGE was 22.1 kDa. The optimum activity was at pH 6.5 and 45°C. The enzyme was stable at 40°C with half-life of 35 min, and in the pH range from 4.5 to 10.0. The activity was increased in the presence of Mg+2 and Mn+2 and reducing agents such as DTT and ßmercaptoethanol, but it was reduced by Cu+2 and Pb+2 . The xylanase presented Km of 2.3 mM and Vmax of 731.8 U·mg·prot-1 with birchwood xylan as substrate. This xylanase presented differences in its properties when it was compared to the xylanases from other P. chrysogenum strains. Conclusion: The xylanase from P. chrysogenum F-15 showed lower enzymatic activity on commercial xylan than on hemicellulose from agroindustry biomass and its biochemistry characteristics, such as stability at 40°C and pH from 4.0 to 10.0, shows the potential of this enzyme for application in food, feed, pulp and paper industries and for bioethanol production.
Assuntos
Penicillium chrysogenum/metabolismo , Polissacarídeos/metabolismo , Endo-1,4-beta-Xilanases/biossíntese , Temperatura , Estabilidade Enzimática , Biomassa , Endo-1,4-beta-Xilanases/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , HidróliseRESUMO
This research was undertaken to develop tools that facilitate the industrial application of an immobilized loofah-fungi system to degrade Direct Black 22 (DB22) azo dye. In laboratory-scale tests, the DB22, and loofah as support, were used. Assays without loofah were used as a free-cells control. The use of natural carriers to facilitate adhesion and growth of the fungi has shown favorable results. The degradation rate of immobilized cells increased twice as compared to free-cells control. At day 5 the decolorization was almost complete, while without loofah the total decolorization took more than 10 days. After 10 days, the extent of growth was nine times higher for the immobilized assays in comparison with the control flask. In subsequent experiments decolorization of DB22 was proven in a bench-scale reactor. A previously developed kinetic model was validated during the process. The model validation over free-cells assays gives an average normalized root mean squared error (ANRMSE) of 0.1659. Recalibration steps allowed prediction of the degradation with immobilized cells, resulting in an ANRMSE of 0.1891. A new calibration of the model during the scaling-up process yielded an ANRMSE of 0.1136 for DB22. The results presented encourage the use of this modeling tool in industrial scale facilities.
Assuntos
Células Imobilizadas/metabolismo , Corantes/análise , Naftalenos/análise , Penicillium chrysogenum/metabolismo , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Compostos Azo , Reatores Biológicos/microbiologia , Corantes/metabolismo , Cinética , Luffa/química , Modelos Teóricos , Naftalenos/metabolismo , Poluentes Químicos da Água/metabolismoRESUMO
Background: Many buildings in Egypt e.g. museums, mosques and churches, do not possess controlled environments for minimizing the risks of damage of wooden artifacts due to the growth of fungi. Fungal damage usually appears as change in wood color, appearance of stains, and sometimes deformation of wooden surfaces. In this study we focused on the effect that some fungi exert on the properties of wooden artifacts and evaluated the effectiveness of different concentrations of chitosan on their protection against damage by mold fungi. Results: Samples were collected from different monuments and environments, and fungi growing on them were isolated and identified. The isolated Penicillium chrysogenum, Aspergillus flavus and /Aspergillus niger strains were used for the infestation of new pitch pine samples. The results revealed that the lightness of samples infected with any of the tested fungi decreased with increasing incubation times. XRD analysis showed that the crystallinity of incubated samples treated individually with the different concentrations of chitosan was lower than the crystallinity of infected samples. The crystallinity index measured by the first and the second method decreased after the first and second months but increased after the third and fourth months. This may due to the reducing of amorphous part by enzymes or acids produced by fungi in wooden samples. Conclusions: The growth of fungi on the treated wood samples decreased with increasing the concentration of chitosan. Hence, it was demonstrated that chitosan prevented fungal growth, and its use could be recommended for the protection of archeological wooden artifacts.