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OBJETIVO: O objetivo foi sintetizar as evidências na literatura sobre as estratégias de ensino das lutas e dos esportes de combate. MÉTODOS: Foi realizada uma busca nas bases de dados da Biblioteca Virtual de Saúde (BVS) que inclui LILACS, MEDLINE, MEDCARIB, OPAS/OMS, PAHO e WHOLIS; SciELO, EBSCO e Periódicos da CAPES no período entre 2010 e 2020. Para a busca utilizou-se a combinação dos seguintes termos: “Artes Marciais” OR “Esportes de Combate”; “Martial Arts” OR “Combat Sports”. RESULTADOS: Os resultados mostraram que 89% dos estudos apontam para estratégias de ensino centradas no aluno, levando em conta os interesses e contextualizando as práticas, de forma lúdica e livre para criar novos movimentos. CONCLUSÃO: As lutas e os esportes de combate através de metodologias e estratégias de ensino centradas nos alunos beneficiam o desenvolvimento integral de seus praticantes.Pedagogical methodologies and strategies for teaching fights, martial arts and fighting sports: an integrative reviewABSTRACTOBJECTIVE: This integrative review aimed at synthetizing the evidence in the literature on strategies for teaching fighting and combat sports. METHODS: A search on the databases of the Virtual Health Library (VHL) was carried out, which included LILACS, MEDLINE, MEDCARIB, OPAS/WHO, PAHO and WHOLIS, ScIELO, EBSCO, in addition to the Journals of CAPES from 2010 to 2020. For the search we used the combination of the following terms: “Martial Arts” OR “Combat Sports”. RESULTS: The results showed that 89% of the studies point to student-centered teaching methods that consider interests and contextualized practices in a playful and free manner to create new movements. CONCLUSION: In conclusion, fights and combat sports through methodologies and teaching strategies centered on students benefit the integral development of their practitioners.

Ochratoxin A (OTA) is a mycotoxin with a serious impact on human health. In Mediterranean countries, the black Aspergilli group, in particular Aspergillus carbonarius, causes the highest OTA contamination. Here we describe the synthesis of three polyphenolic flavonoids: 5-hydroxy-6,7-dimethoxy-flavone (MOS), 5,6-dihydroxy-7-methoxy-flavone (NEG), and 5,6 dihydroxy-flavone (DHF), as well as their effect on the prevention of OTA biosynthesis and lipoxygenase (LOX) activity in A. carbonarius cultured in a conducive liquid medium. The best control effect on OTA biosynthesis was achieved using NEG and DHF. In fungal cultures treated with these compounds at 5, 25, and 50 &mu, g/mL, OTA biosynthesis significantly decreased throughout the 8-day experiment. NEG and DHF appear to have an inhibiting effect also on the activity of LOX, whereas MOS, which did not significantly inhibit OTA production, had no effect on LOX activity. The presence of free hydroxyls in catecholic position in the molecule appears to be a determining factor for significantly inhibiting OTA biosynthesis. However, the presence of a methoxy group in C-7 in NEG could slightly lower the molecule&rsquo, s reactivity increasing OTA inhibition by this molecule at 5 &mu, g/mL. Polyphenolic flavonoids present in edible plants may be easily synthesized and used to control OTA biosynthesis.

Ochratoxin A (OTA) contamination in raisins is related to the presence of black Aspergilli. In this work, raisin samples belonging to the cultivars 'Sublime seedless', 'Sultanine' and 'Centennial' were collected from different regions in Algeria and analyzed for the presence of OTA-producing black Aspergilli and of OTA. Black Aspergilli were found in all the samples with differences between cultivars and sampling regions. Generally, Aspergillus carbonarius was the most frequently isolated species among black Aspergilli. About 86.7% of A. carbonarius isolates and 72.2% of A. niger isolates were OTA producers. We also investigated the effect of ozone (0.3 ppm) treatment on the ability of conidia to germinate. Ozone significantly controlled the ability of conidia to germinate of both OTA producing and non-producing isolates. These results underline the need to establish a limit for OTA contamination in raisins in Algeria and highlight the potential of 03 to control fungal contaminants, especially those responsible for OTA production.

Two ochratoxin A (OTA)-producing Aspergillus isolates, recently collected from submerged riparian decomposing leaves in Italy, were found to have a similar morphology to Aspergillus cretensis (subgenus Circumdati, section Circumdati). However, marked differences emerged between these two novel isolates and A. cretensis as the former displayed different colony features and had larger vesicles, metulae, phialides and conidia, as well as a distinct sclerotial form and size. In order to determine the taxonomic status and to infer the evolutionary relationships of these two morphologically identical isolates, a molecular phylogenetic analysis was performed on all the officially recognized lineages in the section Circumdati. The DNA sequences and the deduced amino acid residues from the nuclear loci were analysed. Both rRNA and protein coding genes were assessed, which are widely used to differentiate taxa belonging to genus Aspergillus at various evolutionary levels. The 5.8S rDNA gene and internal transcribed spacers (ITS), the D1/D2 domains of the 28S rDNA gene, a region of the tubulin beta chain gene (benA) and part of the calmodulin gene (cmd) were amplified by PCR and then sequenced. The analysis of the rRNA regions and of the benA and cmd sequence data indicated that the two isogenic isolates belonged to a genetically distinct OTA-producing species of the genus Aspergillus. The isolates are proposed as representing a novel species, Aspergillus affinis sp. nov., with the type strain ATCC MYA-4773T ( = CBS 129190 = 417). Phylogenetically, A. affinis sp. nov. appeared to be very closely related to A. cretensis, from which it could be distinguished by means of a morphological trait analysis.

Objectives The contamination of agricultural commodities with mycotoxins can occur without visible fungal contamination. Therefore, it is very important to develop a method for detecting very low levels of Aspergillus carbonarius DNA, which is the main agent responsible for ochratoxin A contamination in grape and wine. Methods The aim of this study was to detect the presence of A. carbonarius in grapes early during different stages of fungal development by the SYBR s Green real-time polymerase chain reaction or quantitative polymerase chain reaction approach by designing species-specific primers (Acpks) on the basis of the polyketide synthase sequences. Results The real-time polymerase chain reaction amplification results show early detection of a specific A. carbonarius from nonsymptomatic grape berries harvested directly from the field. Moreover, the amplification of fungal DNA extracted from grape berries artificially inoculated with A. carbonarius has shown an amplification starting from 6h after inoculation, i.e. when the mycelium is not yet visible under stereomicroscope ( � 100) observation. Conclusion The results indicate that these highly specific and sensitive polymerase chain reaction-based methods are able to discriminate grape berries infected with A. carbonarius from uninfected ones. Thus, in a working day, it is possible to harvest the berries, extract high-quality DNA and perform A. carbonarius-specific real-time polymerase chain reaction amplification. The method proposed in this work could contribute toward food safety (e.g., wine and table grapes) because it could be used to predict the potential risk of contamination by potentially ochratoxigenic strains of A. carbonarius.

The main objective of this work was to develop a protocol for the detection and quantification of ochratoxin A (OTA) to be used directly in food commodities, where sensitivity and robustness are critical factors. In this study, the contamination of wine grapes (var. Merlot) by OTA producer Aspergillus carbonarius was detected by PCR on asymptomatic grape berries. Four varieties of Vitis vinifera harvested directly from the field were used in the PCR-based assay. In the experiments, A. carbonarius was used to develop the PCR method, and Aspergillus niger strain 7096 and other species isolated from grapes were also used to test the specificity of the method presented below. The multiplex PCR reaction was tested on fungal DNA by amplifying two target genes in order to differentiate with an higher degree of effectiveness potentially ochratoxigenic black Aspergilli from other fungal contaminants. These PCR-based assays showed high sensitivity and effectiveness in detecting A. carbonarius from grape DNA. The same grape berries in which A. carbonarius DNA was revealed at an early timepoint showed the visible presence of black rot after appropriate incubation, confirming the results obtained by the molecular methods developed here. Furthermore, OTA detection on Merlot wine was performed with a novel device based on the use of an amorphous silica photosensor. This technique, using very simplified and rapid extraction procedures, allowed the detection and quantification of OTA from wine contaminated at 2 ppb. These methods allow rapid and early detection of the presence of the pathogen and of the toxin within a working day.

Objectives The aim of this research was to set up a polymerase chain reaction (PCR)-based method to early investigate the presence of Aspergillus carbonarius in grapes. Polymerase chain reaction-based methods that target DNA are considered a good alternative with respect to traditional diagnostic methods for the early detection of pathogens because of their high specificity and sensitivity. Methods In this study, two polymerase chain reaction assays to detect the presence of A. carbonarius in grapes have been developed by using species-specific primers designed on the basis of Internal Transcribed Spacers of rDNA units and on a polyketide synthase gene responsible for ochratoxin A biosynthesis. Primers specificity was evaluated by polymerase chain reaction on A. carbonarius DNA as template and then on DNA extracted from A. carbonarius– contaminated and uncontaminated grape berries. The developed polymerase chain reaction method was used to analyze the detection limits of A. carbonarius DNA directly on grapes. Results Polymerase chain reaction amplification allows a clear detection of A. carbonarius DNA 24 hours after inoculum on grapes, i.e. when the fungus is not yet visible. Conclusion Early detection by polymerase chain reaction of the ochratoxin A producer fungus A. carbonarius could help to achieve an effective control of the fungal contamination, particularly concerning mycotoxigenic fungi.

Penicillium expansum is a post-harvest pathogen of apples which can produce the hazardous mycotoxin patulin. The yeast Cryptococcus laurentii (LS28) is a biocontrol agent able to colonize highly oxidative environments such as wounds in apples. In this study culture filtrates of the basidiomycete Lentinula edodes (LF23) were used to enhance the biocontrol activity of LS28. In vitro L edodes culture filtrates improved the growth of C. laurentii and the activity of its catalase, superoxide dismutase and glutathione peroxidase, which play a key role in oxidant scavenging. In addition. LF23 also delayed P. expansum conidia germination. The biocontrol effect of LS28 used together with LF23 in wounded apples improved the inhibition of P. expansum growth and patulin production in comparison with LS28 alone, under both experimental and semi-commercial conditions. The biocontrol effect was confirmed by a semi-quantitative PCR analysis set up for monitoring the growth of P. expansum. (c) 2010 Elsevier B.V. All rights reserved.

In Aspergillus nidulans, Aspergillus flavus, and Aspergillus parasiticus, lipoperoxidative signalling is crucial for the regulation of mycotoxin biosynthesis, conidiogenesis, and sclerotia formation. Resveratrol, which is a lipoxygenase (LOX) and cyclooxygenase inhibitor, downmodulates the biosynthesis of ochratoxin A (OTA) in Aspergillus ochraceus. In the genome of A. ochraceus, a lox-like sequence (AoloxA ; National Center for Biotechnology Information (NCBI) accession number: DQ087531) for a lipoxygenase-like enzyme has been found, which presents high homology (100 identities, 100 positives %, score 555) with a lox gene of Aspergillus fumigatus (NCBI accession number: XM741370). To study how inhibition of oxylipins formation may affect the A. ochraceus metabolism, we have used a DeltaAoloxA strain. This mutant displays a different colony morphology, a delayed conidia formation, and a high sclerotia production. When compared to the wild type, the DeltaAoloxA strain showed a lower basal activity of LOX and diminished levels of 13-hydroperoxylinoleic acid (HPODE) and other oxylipins derived from linoleic acid. The limited oxylipins formation corresponded to a remarkable inhibition of OTA biosynthesis in the DeltaAoloxA strain. Also, wheat seeds (Triticum durum cv Ciccio) inoculated with the DeltaAoloxA mutant did not accumulate 9-HPODE, which is a crucial element in the host defence system. Similarly, the expression of the pathogenesis-related protein 1 (PR1) gene in wheat seeds was not enhanced. The results obtained contribute to the current knowledge on the role of lipid peroxidation governed by the AoloxA gene in the morphogenesis, OTA biosynthesis, and in host-pathogen interaction between wheat seeds and A. ochraceus.

Fusapyrone (FP), an antifungal natural compound, was tested against the three main ochratoxigenic species of the Aspergillus section Nigri . The MICs at 24 h were 6.0, 11.6, and 9.9 μg/ml for Aspergillus carbonarius , Aspergillus tubingensis , and Aspergillus niger , respectively. Strong inhibition of growth and morphological changes were still observed at half the MIC after 7 days. The application of a 100 μg/ml FP solution in a laboratory assay on artificially inoculated grapes resulted in a significant reduction (up to 6 orders of magnitude) of A. carbonarius CFU counts. Dramatic reductions of the ochratoxin A (OTA) content, compared to the content of the positive control (average amount of OTA, 112.5 ng/g of grape; three experiments), were obtained with the application of either 100 or 50 μg/ml of FP (0.6 or 5.1 ng/g of grape, respectively).

It is demonstrated that, in fungal cells grown in synthetic media, the Apyap1 gene is implicated in the modulation of aflatoxin biosynthesis following the perturbation of redox balance. This study suggests that an association between oxidative stress and aflatoxin biosynthesis also occurs in maize seeds. We used DeltaApyap1, a strain in which the gene Apyap1 was disrupted, to verify whether this oxidative stress-related transcription factor, by affecting cell redox balance, can have a role in the modulation of aflatoxin synthesis. The amount of hydroperoxides (ROOH) produced by wild type (WT) and DeltaApyap1, both grown in potato dextrose broth, was assayed in the filtrate. In maize seeds (30 g), inoculated with WT and DeltaApyap1conidia and incubated at 30 degrees C for 15 days, lipoxygenase activity (LOX), lipoperoxides (LOOH) production, fungal growth and aflatoxin biosynthesis was analysed. It was observed that DeltaApyap1 released more hydroperoxides in the culture media and more aflatoxins in seeds, possibly through stronger stimulation of LOX, which, in turn led to greater LOOH production in the seeds. On the basis of the results, a hypothesis regarding strategies to control aflatoxin synthesis is formulated.

Fungal growth on cereal grains decreases their nutritional value and constitutes health hazards, probably, because of the production of toxic metabolites (mycotoxins). Therefore, attempts are coming out to detect and quantify the degree of fungal infection at the early stage of mold infection. One of the most promising techniques is the analysis of volatile compounds in the headspace gas surrounding the samples. The aim of this work was to study the possibility of the application of electronic nose for an early detection of volatile compounds in infected samples and to discriminate between non-infected and infected samples with two different species of fungi (Penicillium chrysogenum and Fusarium verticillioides). Moreover, GC–MS analysis of the headspaces of the same samples confirmed that electronic nose as a powerful tool is able to provide satisfactory indications about the rate of contamination.

Biosynthesis of aflatoxins, toxic metabolites produced by Aspergillus parasiticus, is correlated to the fungal oxidative stress and cell ageing. In this paper, the mechanism underlying the aflatoxin-inhibiting effect of the Lentinula edodes culture filtrates was studied by analysing their anti-oxidant activity and beta-glucan content. Mushroom beta-glucans are pharmacologically active compounds stimulating anti-oxidant responses in animal cells. L. edodes lyophilised filtrates stimulate A. parasiticus anti-oxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase) and aflatoxin inhibition was better correlated with beta-glucan content than with anti-oxidant activity of the filtrates. RT-PCR analyses on treated mycelia showed a delay in the activation of aflR, and norA, genes of aflatoxin cluster and a synchronous activation of hsf2-like, a homologue of a yeast transcription factor involved in oxidative stress responses. The first evidence of hsf2- like in A. parasiticus and its activation during aflatoxin biosynthesis is reported. L. edodes filtrates could play a role as external stimulus affecting the anti-oxidant status in the fungal cell that, in turn, leads to aflatoxin inhibition. In the fungal cell, beta- glucans present in the filtrates could stimulate the activation of transcription factors related to anti-oxidant response and anti-oxidant enzyme activity with a contemporaneous delay of aflatoxin genes transcription, which led to a marked reduction of aflatoxin production. This research suggests new perspectives to set suitable strategies against aflatoxins and L. edodes could be considered a promising tool.

Plant responses to biotic and abiotic stress can be mediated by oxidised products and in this study we analysed the relation among some of them and the growth factor indole-3-acetic acid (IAA). The plant material used was potato tuber sliced below bud and incubated for different lengths of time before analysis. Wounding in potato tuber leads, in a very short time (0–30 min), to the generation of lipid hydroperoxides (LOOH) from polyunsaturated fatty acids (PUFA). These reactive species could cause a subsequent increase of 9 and 13-lipoxygenase (LOX, E.C.1.13.12.12.), analysed by RT-PCR and spectrophotometric assay, LOOH, Jasmonates and IAA all quantified by GC–MS analysis. The activation of 9 and 13-LOX, using different timing, leads to the formation of LOOH with a subsequent generation of jasmonates and IAA as highlighted by the addition on the potato tuber slices of salicylhydroxamic acid (SHAM), an inhibitor of LOX activity. A correlation between jasmonates and IAA resulted by testing their reciprocal influence during wounding in potato tuber. The relationship occurring among each hormone analysed during wounding underlines the fact that the jasmonates level can be regulated in situ and this can suggest a role for these compounds in potato tuber which has been underestimated up to now.

Among the various factors correlated with toxin production in fungi, oxidative stress is a crucial one. In relation to this, an important role is played by oxidative stress-related receptors. These receptors can transduce the "oxidative message" to the nucleus and promote a transcriptional change targeted at restoring the correct redox balance in the cell. In Aspergillus parasiticus, the knockout of the ApyapA gene, a homologue of the yeast Yap-1, disables the fungus's capacity to restore the correct redox balance in the cell. As a consequence, the onset of secondary metabolism and aflatoxins synthesis is triggered. Some clues as to the involvement of oxidative stress in the regulation of ochratoxin A (OTA) synthesis in Aspergillus ochraceus have already been provided by the disruption of the oxylipin-producer AoloxA gene. In this paper, we add further evidence that oxidative stress is also involved in the regulation of OTA biosynthesis in A. ochraceus. In fact, the use of certain oxidants and, especially, the deletion of the yap1-homologue Aoyap1 further emphasize the role played by this stress in controlling metabolic and morphological changes in A. ochraceus. © 2012 Springer-Verlag.

A bacterium isolated from patulin-contaminated apples was capable of degrading patulin to a less-toxic compound, ascladiol. The bacterium was identified as Gluconobacter oxydans by 16S rRNA gene sequencing, whereas ascladiol was identified by liquid chromatography-tandem mass spectrometry and proton and carbon nuclear magnetic resonance. Degradation of up to 96% of patulin was observed in apple juices containing up to 800 μg/ml of patulin and incubated with G. oxydans .

The inhibition of some fungal strains responsible for paper biodeterioration is reported. Antimicrobials (butylated hydroxytoluene, BHT and butylated hydroxyanisole, BHA), azole antifungals (econazole, miconazole and ketoconazole) and chitin synthase inhibitors (uridine, Sfluorouridine, 2-deoxyuridine) have been assessed for efficacy against Penicillium chrysogenum Thorn, Aspergillus terreus Thorn, Stachybotrys atra Corda and Chaetomium elatum Kunze, fungal strains isolated from deteriorated papers. Our results have shown that the most evident inhibitin 9 effect on fungal growth has been obtained with miconazole and econazole at lo- M. 0 1997 Published by Elsevier Science Limited

Mycotoxins, secondary metabolites produced by some filamentous fungi during their growth on food and feed commodities, represent a serious health hazard due to their possible cytotoxic and genotoxic effects for human and animals. The presence of some mycotoxins in foods and feeds can induce tumours, immune suppression and lowering of animal production. The levels of different mycotoxins, like aflatoxins, ochratoxin A and fusarium toxins in food and feed commodities are limited by law. Up to day the control of the mycotoxins in foods and feeds is mainly achieved by the use of chemical compounds. This strategy could arise environmental problems and select fungal strains resistant to their effects. Some natural compounds like mushroom beta-glucans and plant derived antioxidants have demonstrated the ability to provide a long lasting control of the biosynthesis of different mycotoxins, both in vitro and on stored maize and wheat seeds. Furthermore, mushroom' beta-glucans have proven a significant immune-enhancing effects on human and animal cells. Thus, their use in a challenge against mycotoxins could provide not only the control of these secondary metabolites but also an improvement of animal well-being.

The paper reports the results of a study performed to investigate the influence of the grape variety on the growth of Aspergillus carbonarius on grape berries and the correlation between the amount of ochratoxin A (OTA) and the content of trans-resveratrol produced after fungal contamination. Variations in the amount of OTA produced by the fungus are observed depending on both grape variety and on the induction of trans-resveratrol determined during the infection. The obtained data suggest that if an increase in trans-resveratrol production in grape berries occurs early after the fungal infection, the berry exploits this compound to control OTA synthesis. If the increase in trans-resveratrol concentration is delayed after fungal infection (40 h), a control of OTA accumulation can not be achieved. The possibility of exerting significant control of OTA biosynthesis by this phytoalexin seems to rely in the promptness of its production, as occurs also in other fungus plant interactions and, in turn, seems to be dependent also on grape cultivar. In this fungus-plant system, trans-resveratrol appears to represent a defence-related compound toward A. carbonarius and OTA contamination.

Although the strategies routinely adopted to limit production of carcinogenic aflatoxins by Aspergillus parasiticus and Aspergillus flavus in foods and feeds can be quite effective, they are often neither environmentally friendly, nor non-toxic for end users. Polysaccharides and glycoproteins, particularly β-glucans from the basidiomycete Lentinula edodes, already known for their health-promoting effects on animals and humans, have previously demonstrated the ability to inhibit aflatoxin biosynthesis by stimulating the antioxidant defences of the toxigenic fungus. Here the results of a study regarding the influence on polysaccharide production by L. edodes of oxidative stress induced using paraquat (PQ) treatment are reported. Paraquat 0.5 and 1 mM resulted in an enhancement of the expression of the β-glucan synthase gene Lefks1 and a consequent stimulating effect (about 30-35%) on β-glucans production. Moreover, oxidative-stress (PQ) induced polysaccharides have a higher aflatoxin inhibiting capacity in two different strains of A. parasiticus in comparison with non-induced polysaccharides. This more efficient inhibition might be explained by a higher content of β-glucans because 1H-NMR analysis revealed no obvious qualitative differences between PQ-induced and non-induced polysaccharides. The results obtained show promise for improving the quantity and efficiency of L. edodes extracts in order to achieve enhanced control over aflatoxin biosynthesis in foods and feeds using health-promoting and environmentally-friendly compounds.

International audience; Aspergillus carbonarius and A. niger aggregate are the main fungal contaminants in table grapes. Besides their ability to cause the Black rot, they can produce Ochratoxin A (OTA), a mycotoxin that has attracted increasing attention worldwide. The objective of this work was to set up a simple and rapid molecular method for the early detection of both fungi in table grapes before fungal development becomes evident. PCR-based assays were developed by designing species-specific primers based on the polyketide synthases (PKSS) sequences of A. carbonarius and A. niger that have recently been demonstrated to be involved in OTA biosynthesis. Three table grape varieties (Red globe, Crimson seedless and Italia) were inoculated with A. carbonarius and A. niger aggregate isolates strains producing OTA.. Samples were collected 0, 3, 6, 9 and 12 days after inoculation. The extracted DNA extracted from control (non-inoculated) and from inoculated grapes was amplified by PCR using ACPKS2F-ACPKS2R for A. carbonarius and ANPKS5-ANPKS6 for A. niger aggregate. Both primers allowed a clear detection even in symptomless samples. Since the high specificity and sensitivity of PCR-based methods, they are considered to be a good alternative to traditional diagnostic means for the early detection of fungi in complex matrix. The results obtained could be useful for the definition of a "quality label" for tested grapes to improve the safety measures taken to guarantee the production of fresh table grapes.

Fungi can grow on many food commodities. Some fungal species, such as Aspergillus flavus, Aspergillus parasiticus, Aspergillus niger and Fusarium spp., can produce, under suitable conditions. mycotoxins, secondary metabolites which are toxic for humans and animals. Toxigenic fungi are a real issue, especially for the cereal industry. The aim of this work is to carry out a non destructive, hyperspectral imaging-based method to detect toxigenic fungi on maize kernels, and to discriminate between healthy and diseased kernels. A desktop spectral scanner equipped with an imaging based spectrometer ImSpector-Specim V10, working in the visible-near infrared spectral range (400-1000 nm) was used. The results show that the hyperspectral imaging is able to rapidly discriminate commercial maize kernels infected with toxigenic fungi from uninfected controls when traditional methods are not yet effective: i.e. from 48 h after inoculation with A. niger or A. flavus. (C) 2010 Elsevier B.V. All rights reserved.

Mycotoxins are harmful secondary metabolites produced by a range of widespread fungi belonging in the main to Fusarium, Aspergillus and Penicillium genera. But why should fungi produce toxins? And how is the biosynthesis of these toxins regulated? Several separate factors are now known to be capable of modulating mycotoxin synthesis ; however, in this study, focussing just on mycotoxins whose regulatory mechanisms have already been established, we introduce a further factor based on a novel consideration. Various different mycotoxin biosynthetic pathways appear to share a common factor in that they are all susceptible to the influence of reactive oxygen species. In fact, when a fungus receives an external stimulus, it reacts by activating, through a well-defined signal cascade, a profound change in its lifestyle. This change usually leads to the activation of global gene regulators and, in particular, of transcription factors which modulate mycotoxin gene cluster expression. Some mycotoxins have a clear-cut role both in generating a pathogenetic process, i.e. fumonisins and some trichothecenes, and in competing with other organisms, i.e. patulin. In other cases, such as aflatoxins, more than one role can be hypothesised. In this review, we suggest an "oxidative stress theory of mycotoxin biosynthesis" to explain the role and the regulation of some of the above mentioned toxins.

Oxidative stress is recognized as a trigger of different metabolic events in all organisms. Various factors correlated with oxidation, such as the β-oxidation of fatty acids and their enzymatic or nonenzymatic by-products (e.g., precocious sexual inducer factors and lipoperoxides) have been shown to be involved in aflatoxin formation. In the present study, we found that increased levels of reactive oxygen species (ROS) were correlated with increased levels of aflatoxin biosynthesis in Aspergillus parasiticus . To better understand the role of ROS formation in toxin production, we generated a mutant (ΔAp yapA ) having the Ap yapA gene deleted, given that Ap yapA orthologs have been shown to be part of the antioxidant response in other fungi. Compared to the wild type, the mutant showed an increased susceptibility to extracellular oxidants, as well as precocious ROS formation and aflatoxin biosynthesis. Genetic complementation of the ΔAp yapA mutant restored the timing and quantity of toxin biosynthesis to the levels found in the wild type. The presence of putative AP1 (ApYapA orthologue) binding sites in the promoter region of the regulatory gene aflR further supports the finding that ApYapA plays a role in the regulation of aflatoxin biosynthesis. Overall, our results show that the lack of Ap yapA leads to an increase in oxidative stress, premature conidiogenesis, and aflatoxin biosynthesis.

A close correlation between lipoperoxide formation in cells ofAspergillus parasiticus and aflatoxin biosynthesis has been established in rich and poor media in which oxidative stress was induced by addition of cumene hydroperoxide, a lipoperoxidation inducer. The presence of hydroperoxides of linoleic acid inA. parasiticus mycelia was analysed by liquid chromatography-mass spectrometry (LC-MS). This relation appears to be driven by activation of certain oxidative stress related transcription factors, such asyap1-like, skn7-like andhsf2-like. Activation of these factors then leads to the promotion of transcription of genes encoding antioxidant-related enzymes, such as superoxide dismutase, catalase and glutathione peroxidase. The incomplete seavenging of intracellular oxidation inA. parasiticus cells can lead to aflatoxin biosynthesis. The relationship between oxidative stress and aflatoxin biosynthesis is indicated by the high correlation among increased activity of lipoperoxidation and the antioxidant defence system with formation of aflatoxins. With regard to the relationship of oxidative stress and aflatoxin biosynthesis, the mechanism of action of butylated hydroxyl anisole (BHA), an antioxidant compound, in the control of aflatoxin biosynthesis was also investigated. Results indicate this compound can act, per se, by inhibiting lipoperoxidation and by inducing antioxidative defence responses of the fungal cell.

The genotoxic, mutagenic and cancerogenic aflatoxins produced by Aspergillus parasiticus are not yet efficiently controlled besides the increasing researches on this topic. Aflatoxin production by A. parasiticus is related to oxidative stress and some antioxidants can inhibit their production. Some basidiomycetes as Trametes versicolor used as "healing mushrooms" present beta-glucans and glycoproteins which are responsible for the stimulation of the host immune response. In this work T. versicolor culture filtrates, from different isolates, have been tested on A. parasiticus cultures to assay their inhibiting effect on aflatoxin production. Filtrates from T. versicolor were lyophilised and exopolysaccharides and glycoproteins were extracted by subsequent steps and added (2% w/v) to liquid cultures of a toxigenic A. parasiticus strain. Fungal growth and aflatoxins production by A. parasiticus were analysed both in filtrates and in mycelia and no interference on the output of toxins from mycelia was evidenced. Furthermore antioxidant capacity (by crocin test) of the T. versicolor extracts was analysed. All the strains assayed are able to inhibit the toxin production from 40% to above 90% in liquid cultures as well as in maize and wheat seeds inoculated with A. parasiticus. Antioxidant activity and beta-glucans amount in T. versicolor extracts showed a close relationship with aflatoxin inhibition ability and demonstrated that beta-glucans could be involved in aflatoxin inhibition. Molecular data indicate the almost complete inhibition of norA mRNA expression and a delay of aflR mRNA transcription. Filtrates and fractions from T. versicolor could be promising agents in the challenge against aflatoxins.

The efficacy of different antioxidant and antimicrobial substances on the growth of two ochratoxigenic fungi has been investigated. Among the compounds used are some edible and medicinal higher Basidiomycetes mushrooms, Lentinus edodes (Berk.) Sing., Agrocybe aegerita (Brig.) Sing., and Pleurotus eryngii (DC.: Fr) Quel., whose antimicrobial and antioxidant properties have already been reported. The experimental results obtained indicate that some antioxidants and some edible and medicinal mushroom extracts can inhibit the growth of the two tested toxigenic microfungi species, Aspergillus ochraceus and Penicillium verrucosum.

The olive oil mill waste waters (OMW) are byproducts of olive oil industries and represent a pollution problem in all Mediterranean countries, as they are rich of phenols and other organic matter. Among the other compounds, the OMW contain small amounts of lipids (about 2% dry weight), mostly represented by oleic and palmitic acids, which could stimulate fungal growth. The effect of OMW on Lentinus edodes (Berk.) Sing. growth and production of laccase and Mn-peroxidase on liquid and solid cultures media was tested in the studies described in this article. The results showed that OMW are efficient as supply that enhances fungal growth without interfering with the ligninolytic enzyme production and lignin breakdown. The high OMW concentration (50% v/v) on wheat straw did stimulate mycelia growth but resulted in slight inhibition of fruiting body formation, whereas the lower concentration (25% v/v) enhanced both mycelia growth and fruiting body production. From the results obtained OMW could represent a good nutritional source to improve fungal development and their utilization in mushroom production could be an efficient strategy to solve the pollution problem related to OMW.

In order to verify the role played by oxidation in the budding of potato tubers (Solanum tuberosum L. cv. Kennebec), the physiological events occurring below bud at 4 degrees C have been studied for a period of 6 months. The low temperature storage induced an increase in the degree of unsaturation and a decrease in the ratio of saturated/unsaturated fatty acids of membrane polar lipids with a subsequent increase of lipid hydroperoxides (LOOH). Cold stress increased both enzymatic antioxidative activities (superoxide dismutase, SOD, E.C.1.15.1.1; catalase, CAT, E.C.1.11.1.6), and alpha-tocopherol levels thus protecting membrane's polyunsaturated lipids. Between 0 and 15 days of storage SOD/CAT ratio, alpha-tocopherol, LOOH levels and the degree of lipid unsaturation showed strong variations. After 30 to 120/150 days the antioxidative system seemed to reach a homeostasis different from that of time 0, accompanied by a constant increase of indole-3-acetic acid (IAA) after 60 days. The antioxidative system, after 150 days, lost its efficiency while LOOH levels were maintained higher than time 0 and IAA concentration was sufficient to allow sprouting.

Culture filtrates of Lentinus edodes (Berk.) Sing, (shiitake mushroom) added to potato dextrose broth inoculated with a toxigenic strain of Aspergillus parasiticus Speare showed an inhibiting effect on aflatoxin production. Filtrates from 30- (steady conditions) and 15-(shaken conditions)-day-old cultures were the most efficient in inhibiting aflatoxin production by A. parasiticus. Mycelia of L. edodes, incubated on wheat seeds for 20 and 30 days and subsequently inoculated with A. parasiticus, delayed fungal growth of the toxigenic strain and inhibited aflatoxin production. L. edodes represents a promising medicinal mushroom to control the infection by A. parasiticus and the aflatoxin production.

Sur des echantillons de papier de differentes compositions chimiques on a observe le developpement de certains champignons (Aspergillus terreus, Chaetomium elatum, Stachybotrys artra et Penicillium chrysogenum) qui deterioraient le papier. Tous les echantillons etudies, conserves dans un environnement d'un degre d'humidite relativement haut, n'opposaient que tres peu de resistance a l'attaque des champignons et leur permettaient de proliferer. L'addition de certaines nouvelles substances fongicides synthetiques a permis d'enrayer completement le developpement de ces champignons destructeurs de papier.

The response of potato tuber (Solanum tuberosum L. cv. Kennebec) to mechanical wounding was investigated at different times. Changes in the levels of indole-3-acetic acid (IAA), polyunsaturated fatty acids (PUFAs) and lipid hydroperoxides (LOOHs) were monitored up to 120 min after wounding and related to the cytological events occurring up to 24 h. Twenty minutes after injury, an increase in IAA and LOOH levels and a decrease in the levels of PUFAs was observed. Wounding induced mitoses in differentiated (parenchyma) cells starting at 120 min, and promoted an increase of mitotic activity in the meristematic cells (procambium and bud dome), after 360 min. The inhibition of the increase in LOOHs and IAA by lipoxygenase (LOX) inhibitors, as well as the ability of in vitro peroxidated linoleic acid to enhance IAA production, suggest a close relationship among lipoperoxidation, IAA and mitotic activity in the response of potato tuber cells to injury, resulting in a specific growth response, i.e. bud growth and periderm formation.

Background Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. Methods Monosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish oil-treated normal weight group (FO), obese control group (Ob), coconut fat-treated obese group (ObCO) and fish oil-treated obese group (ObFO). Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day) for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. Results Obese animals (Ob) presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt) showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO) similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30%) and triacylglycerol (TG; 33%) compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. Conclusions Low dose of fish oil supplementation (1 g/kg/day) was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.