Development of Loop-Mediated Isothermal Amplification (LAMP) Assays for the Rapid Detection of Toxigenic and in Nuts.

species create major postharvest problems due to the food losses caused by their mere presence and the hazardous mycotoxins they produce, such as aflatoxin B1 (AFB1) and ochratoxin A (OTA). These mycotoxins are mainly produced by and , respectively. In this study, we developed a rapid detection method for the two aforementioned species based on loop-mediated isothermal amplification (LAMP).

Stereocontrolled synthesis of new iminosugar lipophilic derivatives and evaluation of biological activities.

Iminosugars' similarity to carbohydrates determines the exceptional potential for this class of polyhydroxylated alkaloids to serve as potential drug candidates for a wide variety of diseases such as diabetes, lysosomal storage diseases, cancer, bacterial and viral infections. The presence of lipophilic substituents has a significant impact on their biological activities. This work reports the synthesis of three new pyrrolidine lipophilic derivatives O-alkylated in C-6 position.

Silver thiolate nanoclusters as support for chiral ligands: application in heterogeneous phase asymmetric catalysis.

Silver thiolate nanoclusters have been functionalized with a chiral amino alcohol ligand that has previously shown high catalytic efficiency in different asymmetric reactions. The as-developed nanostructured catalyst, which can be easily recovered by simple centrifugation, has been tested in the addition of nitromethane to aromatic aldehydes, showing the same catalytic activity as the homogeneous ligand. Moreover, it was reused for two further recycling cycles without loss of efficiency.

Antifungal and Cytotoxic Activity of Diterpenes and Bisnorsesquiterpenoides from the Latex of Berg.

latex has been extensively utilized in traditional medicine due to its range of bioactivities. Chromatographic separations on silica gel of ethanol extract of latex led to the development of a new procedure for isolating resiniferatoxin () via dried latex and the identification of nine compounds. Among these, catechol (), protocatechuic acid () and 3,4-dihydroxyphenylacetic acid (), known phenolic compounds, were identified for the first time in latex.

Preparation and Asymmetric Induction Evaluation of the First Ephedrine-Based Ligands Immobilized on Magnetic Nanoparticles.

Herein, the synthesis and catalytic activity of two ephedrine-based catalysts and two ephedrine-based magnetic nanoparticle-supported catalysts are reported. All catalysts developed were tested in the addition of diethylzinc to aromatic aldehydes and in the Henry reaction. The homogeneous catalysts showed moderate catalytic activity in the organozinc addition and good activity in the Henry reaction, whereas in the case of the nanocatalyst, it was not effective in the addition of diethylzinc to aldehydes and gave reasonable results in the Henry reaction.

Total stereocontrolled synthesis of a novel pyrrolizidine iminosugar.

Herein we describe a versatile approach to the pyrrolizidine alkaloids skeleton by tailoring our original strategy already used for the pyrrolidine iminosugars synthesis. The key steps are the regio- and stereoselective azidolysis of the suitable chiral vinyl epoxide and then asymmetric dihydroxylation of the corresponding azido alcohol by using (DHQ)AQN as the ligand. Further optimized elaborations addressed to the closure of the two rings allowed us to achieve the target iminosugar with complete stereocontrol.

Antioxidant and Biological Activities of Hydroxytyrosol and Homovanillic Alcohol Obtained from Olive Mill Wastewaters of Extra-Virgin Olive Oil Production.

Some constituents of the Mediterranean diet, such as extra-virgin olive oil (EVOO) contain substances such as hydroxytyrosol (HT) and its metabolite homovanillic alcohol (HA). HT has aroused much interest due to its antioxidant activity as a radical scavenger, whereas only a few studies have been made on the HA molecule. Both chemical synthesis and extraction techniques have been developed to obtain these molecules, with each method having its advantages and drawbacks.

Linear β-amino alcohol catalyst anchored on functionalized magnetite nanoparticles for enantioselective addition of dialkylzinc to aromatic aldehydes.

A linear β-amino alcohol ligand, previously found to be a very efficient catalyst for enantioselective addition of dialkylzinc to aromatic aldehydes, has been anchored on differently functionalized superparamagnetic core-shell magnetite-silica nanoparticles (1a and 1b). Its catalytic activity in the addition of dialkylzinc to aldehydes has been evaluated, leading to promising results, especially in the case of 1b for which the recovery by simple magnetic decantation and reuse was successfully verified.

Stereocontrolled total synthesis of iminosugar 1,4-dideoxy-1,4-imino-D-iditol.

The first stereocontrolled total synthesis of iminosugar 1,4-dideoxy-1,4-imino-D-iditol is described. The key step in our approach was the double diastereoselection in the asymmetric dihydroxylation (AD) of suitable optically active olefin, the chiral vinyl azido alcohol 9. Performing the AD using the most common Cinchona alkaloids as ligands enabled us to identify the ligand of choice for the stereodivergent synthesis of 1,4-dideoxy-1,4-imino-D-iditol and 1,4-dideoxy-1,4-imino-D-galactitol.

Functionalized Magnetic Nanoparticles as Catalysts for Enantioselective Henry Reaction.

With the aim to easily recover and reuse the catalyst, an efficient amino alcohol catalyst previously tested in the asymmetric addition of diethylzinc to several aromatic aldehydes has been immobilized on proper functionalized superparamagnetic core-shell magnetite-silica nanoparticles and employed in the Henry reaction in the semi-homogeneous phase. The nanocatalyst exhibits a promising catalytic activity that remains unchanged in the three catalytic cycles performed. The results prove that highly efficient catalysts, by being immobilized on suitable magnetic nanosupports, can be easily recovered and reused, maintaining their catalytic behavior.

Role of Some Food-Grade Synthesized Flavonoids on the Control of Ochratoxin A in .

Ochratoxin A (OTA) is a mycotoxin with a serious impact on human health. In Mediterranean countries, the black Aspergilli group, in particular , 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 cultured in a conducive liquid medium.

New chiral amino alcohol ligands for catalytic enantioselective addition of diethylzincs to aldehydes.

A study aimed at the synthesis and structure optimization of new, efficient, optically active β-amino alcohol ligands with a structure suitable for immobilization on magnetite nanoparticles has been carried out. The optimized homogeneous amino alcohol catalysts 13a and 13b, the chirality of which arises from the Sharpless epoxidation of suitable allyl alcohols, were tested by employing the well-established enantioselective amino alcohol-promoted addition of diethylzinc to benzaldehyde, giving the corresponding benzyl alcohol with nearly quantitative yield and ee = 95%. Then, their broad applicability as chiral catalysts was evaluated by carrying out the same reaction on a family of aldehydes, including variously substituted aromatic ones as well as an aliphatic analogue.

Advances, challenges and opportunities for point-of-need screening of mycotoxins in foods and feeds.

The assurance of food and feed safety, including the identification and effective monitoring of multiple biological and chemical hazards, is a major societal challenge, given the increasing pace at which food commodities are demanded, produced and traded across the globe. Within this context, mycotoxins are globally widespread secondary fungal metabolites, which can contaminate crops either in the field or during storage and have serious human and animal health impacts such as carcinogenic, teratogenic and hepatotoxic effects. Therefore, their presence in a wide range of foods and feeds is strictly regulated, particularly in the European Union.

Grape variety related trans-resveratrol induction affects Aspergillus carbonarius growth and ochratoxin A biosynthesis.

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.

Aoyap1 regulates OTA synthesis by controlling cell redox balance in Aspergillus ochraceus.

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.

Aspergillus affinis sp. nov., a novel ochratoxin A-producing Aspergillus species (section Circumdati) isolated from decomposing leaves.

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.

Early detection of toxigenic fungi on maize by hyperspectral imaging analysis.

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.

Early detection of Aspergillus carbonarius and A. niger on table grapes: a tool for quality improvement.

Aspergillus carbonarius and A. niger aggregate are the main fungal contaminants of table grapes. Besides their ability to cause black rot, they can produce ochratoxin A (OTA), a mycotoxin that has attracted increasing attention worldwide.

Natural functions of mycotoxins and control of their biosynthesis in fungi.

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.

Lentinula edodes enhances the biocontrol activity of Cryptococcus laurentii against Penicillium expansum contamination and patulin production in apple fruits.

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.

Lipoperoxidation affects ochratoxin A biosynthesis in Aspergillus ochraceus and its interaction with wheat seeds.

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.

Modulation of antioxidant defense in Aspergillus parasiticus is involved in aflatoxin biosynthesis: a role for the ApyapA gene.

Oxidative stress is recognized as a trigger of different metabolic events in all organisms. Various factors correlated with oxidation, such as the beta-oxidation of fatty acids and their enzymatic or nonenzymatic by-products (e.g.

Inhibition of species of the Aspergillus section Nigri and ochratoxin a production in grapes by fusapyrone.

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.

Apyap1 affects aflatoxin biosynthesis during Aspergillus parasiticus growth in maize seeds.

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.

Biotransformation of patulin by Gluconobacter oxydans.

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 microg/ml of patulin and incubated with G.