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Contryphans are bioactive peptides, isolated from the venom of marine snails of the genus Conus, which are characterized by the short length of the polypeptide chain and the high degree of unusual post-translational modifications. The cyclization of the polypeptide chain through a single disulphide bond, the presence of two conserved Pro residues, and the epimerization of a Trp/Leu residue confer to Contryphans a stable and well-defined structure in solution, conserved in all members of the family, and tolerant to multiple substitutions. The potential of Contryphans as scaffolds for the design of redox-active (macro) molecules was tested by engineering a copper-binding site on two different variants of the natural peptide Contryphan-Vn. The binding site was designed by computational modeling, and the redesigned peptides were synthesized and characterized by optical, fluorescence, electron spin resonance, and nuclear magnetic resonance spectroscopy. The novel peptides, named Cupryphan and Arg-Cupryphan, bind Cu(2+) ions with a 1:1 stoichiometry and a K(d) in the 100 nM range. Other divalent metals (e.g., Zn(2+) and Mg(2+)) are bound with much lower affinity. In addition, Cupryphans catalyze the dismutation of superoxide anions with an activity comparable to other nonpeptidic superoxide dismutase mimics. We conclude that the Contryphan motif represents a natural robust scaffold which can be engineered to perform different functions, providing additional means for the design of catalytically active mini metalloproteins.

Sono stati analizzati 273 oli italiani delle stagioni 2009 e 2010. Le analisi IRMS hanno individuato una correlazione tra ?13C, ?18O e latitudine, temperatura e pioggia, valutando anche l'effetto stagionale. I campioni del nord hanno una composizione isotopica più leggera di carbonio e ossigeno, quelli delle isole sono più arricchiti in entrambe le annate. Si sono distinte quattro aree geografiche: nord, isole, sud Tirreno e centro-sud Adriatico. Le analisi NMR hanno definito simili classi geografiche, hanno monitorato l'effetto stagionale e le variabili caratteristiche per ogni regione. Gli oli sardi mostrano una maggiore concentrazione di squalene e acido linoleico, gli oli toscani sono ricchi di terpeni 2 e 1, ? sitosterolo e cere, gli oli calabresi mostrano valori di terpeni 2 e 3 più bassi rispetto agli altri campioni peninsulari. L'effetto stagionale si osserva nella diminuzione della concentrazione delle aldeidi tra il primo e il secondo anno in tutte le regioni tranne la Sicilia. In generale la differenza stagionale si nota per Toscana, Lombardia, Molise, Sicilia e Sardegna. Nel Lazio e nella Puglia la differenza è meno netta. Gli oli della Calabria sono gli unici che non mostrano alcun effetto stagionale. L'effetto delle cultivar è stato studiato da entrambe le tecniche.

The 1H-NMR methodology used in the study of genetically modified (GM) foods is discussed. Transgenic lettuce (Lactuca sativa cv "Luxor") over-expressing the Arabidopsis KNAT1 gene is presented as a case study. Twenty-two water-soluble metabolites (amino acids, organic acids, sugars) present in leaves of conventional and GM lettuce were monitored by NMR and quantified at two developmental stages. The NMR spectra did not reveal any difference in metabolite composition between the GM lettuce and the wild type counterpart. Statistical analyses of metabolite variables highlighted metabolism variation as a function of leaf development as well as the transgene. A main effect of the transgene was in altering sugar metabolism.

A new bicyclic sestertepene, named proliferin, has been characterized from Fusarium proliferatum. The pure compound exhibit toxic activity. The structure elucidation of the molecula was accomplished using data from 2D-NMR strategies. Proliferin was shown to have a novel ring skeleton and molecular formula C27H40O5.

Multifarious applications of NMR (high-resolution NMR in liquid-state and in semi-solid matrices, low-field NMR relaxometry, and NMR-imaging) in the analysis of food components and entire food samples are described using examples of different food matrices and different problems related to food safety, traceability, geographical and botanical origin, farming methods, food processing, maturation and ageing, etc. Althoug NMR has not yet been recognized as an official methodology for the food control the numerous applications of NMR reported in the literature show the potenziality of this methodology also as an approach complementary to the other recognized conventional methodologies.

Multifarious applications of NMR (high-resolution NMR in liquid-state and in semi-solid matrices, low-field NMR relaxometry, and NMR-imaging) in the analysis of food components and entire food samples are described using examples of different food matrices and different problems related to food safety, traceability, geographical and botanical origin, farming methods, food processing, maturation and ageing, etc. Althoug NMR has not yet been recognized as an official methodology for the food control the numerous applications of NMR reported in the literature show the potenziality of this methodology also as an approach complementary to the other recognized conventional methodologies.

Se describe en este artículo el descubrimiento de la degradación de la micotoxina patulina por una levadura, The infection of stored apples by the fungus Penicillium expansum causes the contamination of fruits and fruit-derived products with the mycotoxin patulin, which is a major issue in food safety. Fungal attack can be prevented by beneficial microorganisms, so-called biocontrol agents. Previous time-course thin layer chromatography analyses showed that the aerobic incubation of patulin with the biocontrol yeast Rhodosporidium kratochvilovae strain LS11 leads to the disappearance of the mycotoxin spot and the parallel emergence of two new spots, one of which disappears over time. In this work, we analyzed the biodegradation of patulin effected by LS11 through HPLC. The more stable of the two compounds was purified and characterized by nuclear magnetic resonance as desoxypatulinic acid, whose formation was also quantitated in patulin degradation experiments. After R. kratochvilovae LS11 had been incubated in the presence of 13C-labeled patulin, label was traced to desoxypatulinic acid, thus proving that this compound derives from the metabolization of patulin by the yeast. Desoxypatulinic acid was much less toxic than patulin to human lymphocytes and, in contrast to patulin, did not react in vitro with the thiol-bearing tripeptide glutathione. The lower toxicity of desoxypatulinic acid is proposed to be a consequence of the hydrolysis of the lactone ring and the loss of functional groups that react with thiol groups. The formation of desoxypatulinic acid from patulin represents a novel biodegradation pathway that is also a detoxification process.

High consumption of fruit and vegetables has an inverse association with cardiometabolic risk factors. This study aimed to chemically characterize the hydroethanolic extract of P. domestica subsp. syriaca fruit pulp and evaluate its inhibitory activity against metabolic enzymes and production of proinflammatory mediators. Ultra-high-performance liquid chromatography high-resolution mass spectrometry(UHPLC-HRMS) analysis showed the presence of hydroxycinnamic acids, flavanols, and glycoside flavonols, while nuclear magnetic resonance(NMR) analysis showed, among saccharides, an abundant presence of glucose. P. domestica fruit extract inhibited α-amylase, α-glucosidase, pancreatic lipase, and HMG CoA reductase enzyme activities, with IC50 values of 7.01 mg/mL, 6.4 mg/mL, 6.0 mg/mL, and 2.5 mg/mL, respectively. P. domestica fruit extract inhibited lipopolysaccharide-induced production of nitrite, interleukin-1 β and PGE2 in activated J774 macrophages. The findings of the present study indicate that P. domestica fruit extracts positively modulate in vitro a series of molecular mechanisms involved in the pathophysiology of cardiometabolic diseases. Further research is necessary to better characterize these properties and their potential application for human health.

Foods, food ingredients, and their balanced consumption are recognized to have an important role in achieving or maintaining a state of wellbeing by acting as carriers of functional components and bioactive molecules. However, the potential contribution of foods to consumers’ health has so far only been partially exploited. The rapidly evolving scenario of the coronavirus disease 2019 (COVID-19) pandemic is stimulating profound reflection on the relationships between food and the etiological agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, the status of knowledge regarding food as a possible defense/co-therapeutic strategy against the SARS-CoV-2 coronavirus is considered through the discussion of two main current lines of research. One line of research relates to the role of micronutrients, food components, and diets in the strengthening of the immune system through clinical trials; formulations could be developed as immune system enhancers or as co-adjuvants in therapies. The other line of research relates to investigation of the chemical interactions that specific food compounds can have with host or virus targets so as to interfere with the viral infective cycle of SARS-CoV-2. This line requires, as a first step, an in silico evaluation to discover lead compounds, which may be further developed through drug-design studies, in vitro and in vivo tests, and, finally, clinical trials to obtain therapeutic molecules. All of these promising strategies promote the role of food in preventive/co-therapeutic strategies to tackle the COVID-19 pandemic.

The chemical characterization of local Italian potato cultivars is reported to promote their preservation and use as high quality raw material in food industries. Twenty potato (Solanum tuberosum L.) cultivars from Piedmont and Liguria Italian regions were investigated using NMR (Nuclear Magnetic Resonance) and RP-HPLC-PDA-ESI-MSn (Reversed Phase High-Performance Liquid Chromatography with Photodiode Array Detector and Electrospray Ionization Mass Detector) methodologies. Water soluble and lipophilic metabolites were identified and quantified. With respect to literature data, a more complete 1H (protonic) spectral assignment of the aqueous potato extracts was reported, whereas the 1H NMR assignment of potato organic extracts was reported here for the first time. Phenolics resulted to be in high concentrations in the purple&ndash, blue colored Rouge des Flandres, Bergerac, Fleur Bleu, and Blue Star cultivars. Servane, Piatlina, and Malou showed the highest amount of galacturonic acid, a marker of pectin presence, whereas Jelly cultivar was characterized by high levels of monosaccharides. Roseval and Rubra Spes contained high levels of citric acid involved in the inhibition of the enzymatic browning in fresh-cut potato. High levels of the amino acids involved in the formation of pleasant-smell volatile compounds during potato cooking were detected in Rouge des Flandres, Blue Star, Bergerac, Roseval, and Ratte cultivars. These results suggest that each local cultivar is characterized by a proper chemical profile related to specific proprieties that can be useful to obtain high quality industrial products.

The system described in this paper was obtained by soaking calcium alginate (CaAlg) microspheres in a water solution of poly-[(3-acrylamidopropyl)- trimethylammonium chloride-b-N-isopropylacrylamide] [poly(AMPTMA-b-NIPAAM)], a new block co-polymer recently synthesized by atom transfer radical polymerization (ATRP). The block co-polymer is characterized by a lower critical solution temperature (LCST) of 41 °C in aqueous 0.1 M NaCl solution, and can be anchored on the CaAlg microspheres by means of polyion interactions. Polycations (permanently positively charged blocks) and polyanions (free alginate carboxylic groups) interact, leading to microspheres with thermosensitive properties. As an effect of interaction with the microspheres the LCST of the co-polymer is lowered to 36-38 °C. In this temperature range a colloidal water suspension of the microspheres collapses, forming macroscopic aggregates. The new system shows, at human body temperature, an improved ability to carry and deliver both hydrophobic and hydrophilic molecules in comparison with unmodified CaAlg microspheres. The release properties of the microspheres loaded with different model drugs can be appropriately modulated by the amount of the poly(AMPTMA-b-NIPAAM). Furthermore, the microspheres show the interesting capability of retaining the activity of a loaded enzyme (horseradish peroxidase), used as a model protein. The results obtained indicate that the proposed drug delivery system may be suitable for drug depot applications. © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

A portable unilateral nuclear magnetic resonance (NMR) instrument was used to detect in field conditions the water status of leaves of herbaceous crops (Zea mays, Phaseolus vulgaris), mesophyllous trees (Populus nigra), and natural Mediterranean vegetation characterized by water-spending shrubs (Cistus incanus) and water-saving sclerophyllous trees (Quercus ilex). A good relationship was observed between NMR signal, leaf relative water content, and leaf transpiration in herbaceous leaves undergoing fast dehydration or slowly developing a drought stress. A relationship was also observed between NMR signal and water potential of Populus leaves during the development of a water stress and when leaves recovered from the stress. In the natural vegetation, the relationship between NMR signal and water status was found in Cistus, the species characterized by high transpiration rates, when measured during a drought stress period and after a rainfall. In the case of the sclerophyllous Quercus, the NMR signal, the relative water content, and the transpiration rate did not change at different leaf water status, possibly because a large amount of water is compartmentalized in cellular structures and macromolecules. The good association between NMR signal and relative water content was lost in leaves exposed for 24 h to dehydration or to an osmotic stress caused by polyethylene glycol feeding. At this time, the transverse relaxation time became longer than in leaves maintained under optimal water conditions, and two indicators of membrane damage, the ion leakage and the emission of products of membrane lipoxygenation [(Z)-3-hexenal, (Z)-3-hexenol, and (E)-2-hexenol], increased. These results taken all together give information on the physiological state of a leaf under a developing stress and show the usefulness of the NMR instrumentation for screening vegetation health and fitness in natural and cultivated conditions. It is concluded that the portable unilateral NMR instrument may be usefully employed in field conditions to monitor nondestructively the water status of plants and to assist agricultural practices, such as irrigation scheduling, to minimize stomatal closure and the consequent limitation to plant production.

The chemical composition of tea beverage is very complex and not yet completely elucidated. Many factors contribute to the chemical complexity of tea, from plant growth conditions (soil, climate, growth altitude and agricultural practices) and manufacturing processes (drying, steaming, fermentation and storage), to preparation methods (quality of water, infusion time and, not least, the time between tea preparation and consumption). Besides primary metabolites, tea leaves contain a number of secondary metabolites, belonging to many different classes of compounds (such as polyphenols, xanthines, proteic and nonproteic amino acids, sugars, volatile compounds) that are extracted during the infusion and transferred into the beverage. Epidemiological studies have suggested that tea consumption is inversely associated with the risk of developing chronic diseases such as cardiovascular diseases, stroke, some forms of cancer and diabetes. Thus, increasing interest in the health properties of tea resulted in a significant rise in scientific investigation on tea chemical composition. This review article highlights the recent results obtained in the tea beverage characterization using different analytical methodologies. The analytical approaches have been subdivided into two groups: targeted chromatographic and NMR techniques and untargeted NMR analytical approaches. Several examples of untargeted chromatographic techniques coupled with mass spectrometry methodologies are also reported. Advantages, drawbacks and significant applications of the different analytical approaches are discussed.

Patulin is a mycotoxin that contaminates pome fruits and derived products worldwide. Basidiomycete yeasts belonging to the subphylum Pucciniomycotina have been identified to have the ability to degrade this molecule efficiently and have been explored through different approaches to understand this degradation process. In this study, Sporobolomyces sp. strain IAM 13481 was found to be able to degrade patulin to form two different breakdown products, desoxypatulinic acid and ( Z ) - ascladiol. To gain insight into the genetic basis of tolerance and degradation of patulin, more than 3,000 transfer DNA (T-DNA) insertional mutants were generated in strain IAM 13481 and screened for the inability to degrade patulin using a bioassay based on the sensitivity of Escherichia coli to patulin. Thirteen mutants showing reduced growth in the presence of patulin were isolated and further characterized. Genes disrupted in patulin-sensitive mutants included homologs of Saccharomyces cerevisiae YCK2 , PAC2 , DAL5 , and VPS8 . The patulin-sensitive mutants also exhibited hypersensitivity to reactive oxygen species as well as genotoxic and cell wall-destabilizing agents, suggesting that the inactivated genes are essential for tolerating and overcoming the initial toxicity of patulin. These results support a model whereby patulin degradation occurs through a multistep process that includes an initial tolerance to patulin that utilizes processes common to other external stresses, followed by two separate pathways for degradation.

The absolute configuration of fusaproliferin, a toxic metabolite produced by Fusarium proliferation, was determined by the combined use of1H NMR and distance geometry. The configuration of double bonds has been determined in agreement with NOESY buildup data. An R configuration for C10 was determined using Mosher's method. Processing the constraints obtained from NOESY experiments with a distance geometry program, a limited number (80) of possible structures was derived. An agglomerative nonhierarchical method of clustering was used in order to place these structures into classes suggested by the data, and not previously defined in any way. This statistical method showed that indeed the structures could be grouped in four classes. One of these classes is represented by a single structure, with the highest sum of violations and was discarded. All other structures have the same chirality; respectively S for C14 and R for C15. In solution the overall conformation is quite well defined in the region of the five-member ring and the planes of double bonds C2-C3 and C11-C12, while near to C8 and C9 internal flexibility appears evident.

Aqueous solutions of lactose and lysine were refluxed for up to 4 h without pH control. Samples were collected every hour, and the reaction was monitored by measuring the pH, the optical density at 420 nm, and the relative antioxidative efficiency (RAE). The greatest change in optical density and antioxidative efficiency occurred for the mixture heated for 4 h. The 4 h solution was separated into three fractions according to the molecular weights of the components and tested for RAE. The high molecular weight fraction was more colored, and it had the highest antioxidative activity. The low molecular weight fraction was separated by high- performance liquid chromatography (HPLC). RAE values were measured for each purified compound. HPLC coupled with diode array and electrospray mass spectrometry allowed a rapid screening of the solutions and a tentative identification of several peaks. Nuclear magnetic resonance analysis allowed the identification of galactosylisomaltol and pyrraline. The resonance assignments for these compounds were revised.

A new tetracyclic diterpene having molecular formula C 20 H 28 O 2 and molecular mass of 300 a.m.u., has been isolated from culture filtrate of a strain of Trichoderma viride. The pure compound shows antifungal activity; its structure elucidation was accomplished using 2D-NMR strategies and chemical derivatization.

Fusaproliferin is a toxic sesterterpene isolated from Fusarium proliferatum, a widespread pathogen of cereals. Its absolute configuration has been determined by single crystal X-ray diffraction analysis. Fusaproliferin is considered to be a sesterterpene with a new ring skeleton having four C = C double bonds and four chiral atoms. The configurations of the four chiral atoms C10, C14, C15, and C19 are (R), (S), (R), and (S), respectively. In the solid state the macrolide shows a concave hydrophobic surface and hydrophilic convex face. The absolute configuration of C14 and C15 is the same as that observed for retigeranic acid, consistent with fusaproliferin being formed via a sesterterpenic-type biosynthetic pathway.

Extracts from autoclaved maize culture of Fusarium tumidum strain R-5823 were toxic towards Artemia salina. Bioassay-guided fractionation of the organic extract led to the isolation of the toxic compound that was identified as the trichothecene toxin neosolaniol (NEOS) by H-1, C-13 nuclear magnetic resonance spectroscopy and low-resolution electronic impact mass spectrometry. The amount of NEOS produced by the strain R-5823 was 300 mg/kg maize culture, NEOS was also detected by HPLC in cultures of four out of seven additional strains of F. tumidum and Gibberella tumida with different origin, in amounts ranging from 1 to 311 mg/kg. This is the first report on the production of a trichothecene toxin by F. tumidum.

A new toxic sesterterpene, named fusaproliferin, was purified from corn kernel cultures (120 ms/kg dry culture) of a strain of Fusarium proliferatum isolated from com ear rot in northern Italy. The strain, designated ITEM‐1494, also produced fumonisin B., (1.500 mg/kg dry culture) and beauvericin (90 mg/kg dry culture), but not moniliformin. To monitor toxicity, the brine shrimp assay was used throughout the isolation procedure. Fusaproliferin had a molecular formula of C27H40O5, and it is the first sesterterpene isolated from a Fusarium species. © 1995 Wiley‐Liss, Inc.

In the search for potential nucleoside/non-nucleoside mixed type inhibitors of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase, we synthesized a new set of rifamycin S derivatives, containing AZT connected via its hydroxyl at 5′ C, through a spacer, to the third C of rifamycin S. The length of the spacer was eight, nine or 14 atoms. Rifamycin S was also used in its 21, 23-O, O-isopropylidene derivative form, and in one case thymidine replaced AZT. These nucleosidyl rifamycins were weak inhibitors of isolated HIV-1 reverse transcriptase. The inhibitory power was weak most probably because their large molecular volume hindered the inhibition process. With the exception of the thymidine derivative, the AZT derivatives, at concentrations in the range 0.04–0.07 μM, proved non-toxic and inhibited the replication of HIV-1 in C8166 T lymphocytes. This activity appears to be owing to AZT released by the derivatives upon hydrolysis in solution. The present compounds require further development as mixed type reverse transcriptase inhibitors and can be considered non-toxic lipophilic prodrugs of AZT.