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Nucleos(t)ide analogues (NA) belong to a family of compounds widely used in anticancer/antiviral treatments. They generally exhibit a cell toxicity limited by cellular uptake levels and the resulting nucleos(t)ides metabolism modifications, interfering with the cell machinery for nucleic acids synthesis. We previously synthesized purine nucleos(t)ide analogues N7-coordinated to a platinum centre with unaltered sugar moieties of the type: [Pt(dien)(N7-dGuo)]2+ (1; dien = diethylenetriamine; dGuo = 2'-deoxy-guanosine), [Pt(dien)(N7-dGMP)] (2; dGMP = 5'-(2'-deoxy)-guanosine monophosphate), and [Pt(dien)(N7-dGTP)]2- (3; dGTP = 5'-(2'-deoxy)-guanosine triphosphate), where the indicated electric charge is calculated at physiological pH (7.4). In this work, we specifically investigated the uptake of these complexes (1-3) at the plasma membrane level. Specific experiments on HeLa cervical cancer cells indicated a relevant cellular uptake of the model platinated deoxynucleos(t)ide 1 and 3 while complex 2 appeared unable to cross the cell plasma membrane. Obtained data buttress an uptake mechanism involving Na+-dependent concentrative transporters localized at the plasma membrane level. Consistently, 1 and 3 showed higher cytotoxicity with respect to complex 2 also suggesting selective possible applications as antiviral/antitumor drugs among the used model compounds.

Xylella fastidiosa subsp. pauca, is a bacterial phytopathogen associated with the “olive quick decline syndrome” (OQDS) causing severe economic losses to olive groves in Salento area (Apulia, Italy). In a previous work, we analyzed by 1H-NMR the metabolic pattern of naturally infected Ogliarola salentina and Cellina di Nardò susceptible cultivars untreated and treated with a zinc-copper citric acid biocomplex and we observed the treatment related variation of the disease biomarker quinic acid. In this study, we focused also on the Leccino cultivar, known to exhibit tolerance to the disease progression. The 1H-NMR-based metabolomic approach was applied with the aim to characterize the overall metabolism of tolerant Leccino in comparison with the susceptible cultivars Ogliarola salentina and Cellina di Nardò under periodic mid-term treatment. In particular, we studied the leaf extract molecular patterns of naturally infected trees untreated and treated with the biocomplex. The metabolic Leccino profiles were analyzed for the first time and compared with those exhibited by the susceptible Cellina di Nardò and Ogliarola salentina cultivars. The study highlighted a specificity in the metabolic response of the tolerant Leccino compared to susceptible cultivars. These differences provide useful information to describe the defensive mechanisms underlying the change of metabolites as a response to the infection, and the occurrence of different levels of disease, season and treatment effects for olive cultivars.

Considering the growing number of extra virgin olive oil (EVOO) producers in the world, knowing the influence of olive oils with different geographical origins on the characteristics of the final blend becomes an interesting goal. The present work is focused on commercial organic EVOO blends obtained by mixing multiple oils from different geographical origins. These blends have been studied by 1H-NMR spectroscopy supported by multivariate statistical analysis. Specific characteristics of commercial organic EVOO blends originated by mixing oils from Italy, Tunisia, Portugal, Spain, and Greece were found to be associated with the increasing content of the Italian component. A linear progression of the metabolic profile defined characteristics for the analysed samples—up to a plateau level—was found in relation to the content of the main constituent of the Italian oil, the monocultivar Coratina. The Italian constituent percentage appears to be correlated with the fatty acids (oleic) and the polyphenols (tyrosol, hydroxytyrosol, and derivatives) content as major and minor components respectively. These results, which highlight important economic aspects, also show the utility of 1H-NMR associated with chemometric analysis as a powerful tool in this field. Mixing oils of different national origins, to obtain blends with specific characteristics, could be profitably controlled by this methodology.

Hepatocellular carcinoma (HCC) is nowadays the sixth cause of tumour-related deceases worldwide, estimated to become the third in Western countries by 2030. New drugs for HCC treatment still have many adverse effects. Several lines of evidence indicate that plant metabolites offer concrete opportunities for developing new therapeutic strategies for many diseases, including cancer. We previously reported that ethyl acetate extract of a spontaneous edible plant harvested in Apulia, Crithmum maritimum, significantly inhibited cell growth in HCC cells. By 1H-NMR spectroscopy, here we show that Crithmum maritimum ethyl acetate extract counteracts the Warburg effect, by reducing intracellular lactate, inhibits protein anabolism, by decreasing amino acid level, and affects membrane biosynthesis by lowering choline and phosphocholine. Also, we observed an effect on lipid homeostasis, with a reduction in triglycerides, cholesterol, monounsaturated fatty acids (MUFA), and diunsaturated fatty acids (DUFA), and an increase in polyunsaturated fatty acids (PUFA). Taken together, these data demonstrate that Crithmum maritimum-induced cytostasis is exerted through a multi-effect action, targeting key metabolic processes in HCC cells. Overall, our findings highlight the role of Crithmum maritimum as a promising tool for the prevention and the improvement of the therapeutic options for HCC and other types of tumours.

The innovative combination of ultrasound (Us) with a thermal exchanger to produce high quality extra virgin olive oil (EVOO) was studied using Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate analysis (MVA). Major and minor metabolomic components of Apulian Coratina EVOO obtained using the two methods were compared. Early and late olive ripening stages were also considered. An increased amount of polyphenols was found for EVOOs obtained using the Us with respect to the conventional method for both early and late ripening stages (900.8 ± 10.3 and 571.9 ± 9.9 mg/kg versus 645.1 ± 9.3 and 440.8 ± 10.4 mg/kg). NMR spectroscopy showed a significant increase (P < 0.05) in polyunsaturated fatty acids (PUFA) as well as in the tyrosol and hydroxytyrosol derivatives, such as oleocanthal, oleacein, and elenolic acid, for both ripening stages. In conclusion, NMR spectroscopy provides information about the metabolomic components of EVOOs to producers, while the Us process increases the levels of healthy bioactive components.

The Mediterranean basin is one of the regions heavily affected by jellyfish bloom phenomena, mainly due to the presence of scyphozoans, such as Rhizostoma pulmo. The jellyfish have few natural predators, and their bodies represent an organic-rich substrate that can support rapid bacterial growth with great impact on the structure of marine food webs. In Asiatic countries, jellyfish are widely studied for their health benefits, but their nutritional and nutraceutical values still remain poorly characterized. In this study, the differences in the 1H NMR spectroscopy metabolic profiles of R. pulmo female gonads and body fractions (including umbrella and oral arms), in different sampling periods, were studied. For each body compartment both lipid and aqueous extracts were characterized and their 1H NMR metabolic profiles subjected to multivariate analysis. From a statistical analysis of the extracts, a higher contents of &omega, 3 polyunsaturated fatty acids (PUFAs), amino acid and osmolytes (homarine, betaine, taurine) with important roles in marine invertebrates were observed in female gonads, whereas umbrella and oral arms showed similar metabolic profiles. These results support a sustainable exploitation of the jellyfish for the extraction of bioactive compounds useful in nutraceutical, nutricosmetics, and functional food fields.

Jellyfish outbreaks in marine coastal areas represent an emergent problem worldwide, with negative consequences on human activities and ecosystem functioning. However, potential positive effects of jellyfish biomass proliferation may be envisaged as a natural source of bioactive compounds of pharmaceutical interest. We investigated the biochemical composition of mature female gonads and lysozyme antibacterial activity of oocytes in the Mediterranean barrel jellyfish Rhizostoma pulmo. Chemical characterization was performed by means of multinuclear and multidimensional NMR spectroscopy. The ovaries of R. pulmo were mainly composed of water (93.7 &plusmn, 1.9% of wet weight), with organic matter (OM) and dry weight made respectively of proteins (761.76 &plusmn, 25.11 &micro, g mg&minus, 1 and 45.7 &plusmn, 1.5%), lipids (192.17 &plusmn, 10.56 &micro, 1 and 9.6 &plusmn, 0.6%), and carbohydrates (59.66 &plusmn, 2.72 &micro, 1 and 3.7 &plusmn, 0.3%). The aqueous extract of R. pulmo gonads contained free amino acids, organic acids, and derivatives, the lipid extract was composed of triglycerides (TG), polyunsaturated fatty acids (PUFAs), diunsaturated fatty acids (DUFAs), monounsaturated fatty acids (MUFAs), saturated fatty acids (SFAs), and minor components such as sterols and phospholipids. The R. pulmo oocyte lysate exhibited an antibacterial lysozyme-like activity (mean diameter of lysis of 9.33 &plusmn, 0.32 mm corresponding to 1.21 mg/mL of hen egg-white lysozyme). The occurrence of defense molecules is a crucial mechanism to grant healthy development of mature eggs and fertilized embryos (and the reproductive success of the species) by preventing marine bacterial overgrowth. As a corollary, these results call for future investigations for an exploitation of R. pulmo biomasses as a resource of bioactive metabolites of biotechnological importance including pharmaceuticals and nutrition.

Sweet cherries are widely appreciated for fresh consumption as well as for production of juices, jams, jelly fruits and alcoholic beverages. The sweet cherry intake (as fresh fruit and related products) is extensively encouraged for their taste and nutritional qualities, due to the presence of water-soluble (C, B) and fat-soluble (A, E and K) vitamins, carotenoids, polyphenols and minerals, as well as glucose and fructose. However the market often endorses the consumption of a particular sweet cherry cultivar (as for most of vegetables) essentially for organoleptic and/or external appearance rather than nutraceutical qualities. In order to evaluate the potential difference in the nutritional quality of fruits, 56 sweet cherry juice samples from certified trees (Prunus avium L.) of two cultivars (30 from Ferrovia and 26 from Giorgia), grown in the same pedoclimatic Apulian region, were analyzed by 1H NMR spectroscopy and Multivariate Analysis (MVA). Interestingly, despite the usually lower commercial value with respect to the Ferrovia, Giorgia cultivar shows higher content of malic acid and phenolic compounds with important well known nutraceutical properties such as antioxidant activity and stimulating metabolism.

The biological invasion of the green algae Caulerpa cylindracea represents a serious scientific and public issue in the Mediterranean Sea, essentially due to strong modifications both to habitat structure and native benthic communities. Although alterations in health status and changes in flesh quality of some marine species (dietary exposed to C. cylindracea) have been observed, no studies on cause-effect relationships have been carried out. Here, for the first time, through a controlled feeding experiment followed by 1H NMR Spectroscopy and multivariate analysis (PCA, OPLS-DA), we showed that caulerpin taken with diet is directly responsible of changes observed in metabolic profile of fish flesh, including alteration of lipid metabolism, in particular with a reduction of &omega, 3 PUFA content. The potential of caulerpin to directly modulate lipid metabolism opens up new questions about causal mechanism triggered by algal metabolite also in view of a possible exploitation in the nutraceutical/medical field.

A series of pentacoordinate d8 PtII complexes, of the type [PtCl2(η2-CH2=CH2)(Men∩NN)], where Men∩NN = bis-nitrogen ligand, with a variable number of Me groups (i.e., 2,2′-bipyridyl; 1,10-phenanthroline; 6-methyl-2,2′-bipyridyl; 2,9-dimethyl-1,10-phenanthroline; 2,9-dimethyl-1,10-phenanthroline; N,N′-trimethyl-ethylenediamine; N,N,N′,N′-tetramethyl-ethylenediamine; N,N,N′,N′-tetramethyl-1,2-diaminocyclohexane) was studied. The compounds are characterized by variable steric hindrance, due to the variable number (n) of Me substituents, on or ortho to the N-donors of aliphatic diamines or aromatic diimines, respectively. This approach was developed to investigate the interaction of substituents with the metal coordination sphere. With this aim, we analyzed the NMR properties of the considered complexes, with respect to modulation of the metal electron density (195Pt NMR signal frequency) by alkyl groups close to the N-donors. 1H and 13C NMR analysis of the η2-olefin signals has revealed, for each kind of bis-nitrogen ligand, a positive or negative chemical shift variation that is proportional to the number of Me groups geminal or vicinal to the N-donors. Interestingly, the 1JPt,C values increase by approximately 45 Hz for each additional Me on the series of diamine or diimine bis-nitrogen ligands. A rationale for the stability changes observed in such pentacoordinate complexes is suggested, based on the NMR spectroscopic data analysis.

In this work, the reactivity of the Zeise’s salt, K[PtCl 3 (η 2 -C 2 H 4 )], with ketones, in the presence of strong bases, has been studied. In these conditions the formation of metastable intermediate complexes of the type trans -[PtCl 2 {η 1 -CH 2 C(O)R}(η 2 -C 2 H 4 )] − , has been demonstrated by NMR spectroscopy. Further reaction with dinitrogen ligands ( N-N ) gives [PtCl{η 1 -CH 2 C(O)R}( N-N )] complexes. This reactivity of the Zeise’s anion can be exploited for the first general synthesis, in a one pot reaction, of σ-carbon Pt(II) ketonyl derivatives with aliphatic or aromatic dinitrogen ligands (even if sterically hindered).

Xylella fastidiosa subsp. pauca is a xylem-limited bacterial phytopathogen currently found associated on many hectares with the &ldquo, olive quick decline syndrome&rdquo, in the Apulia region (Southern Italy), and the cultivars Ogliarola salentina and Cellina di Nard&ograve, result in being particularly sensitive to the disease. In order to find compounds showing the capability of reducing the population cell density of the pathogen within the leaves, we tested, in some olive orchards naturally-infected by the bacterium, a zinc-copper-citric acid biocomplex, namely Dentamet&reg, by spraying it to the crown, once per month, during spring and summer. The occurrence of the pathogen in the four olive orchards chosen for the trial was molecularly assessed. A 1H NMR metabolomic approach, in conjunction with a multivariate statistical analysis, was applied to investigate the metabolic pattern of both infected and treated adult olive cultivars, Ogliarola salentina and Cellina di Nard&ograve, trees, in two sampling periods, performed during the first year of the trial. For both cultivars and sampling periods, the orthogonal partial least squares discriminant analysis (OPLS-DA) gave good models of separation according to the treatment application. In both cultivars, some metabolites such as quinic acid, the aldehydic form of oleoeuropein, ligstroside and phenolic compounds, were consistently found as discriminative for the untreated olive trees in comparison with the Dentamet&reg, treated trees. Quinic acid, a precursor of lignin, was confirmed as a disease biomarker for the olive trees infected by X. fastidiosa subsp. pauca. When treated with Dentamet&reg, the two cultivars showed a distinct response. A consistent increase in malic acid was observed for the Ogliarola salentina trees, whereas in the Cellina di Nard&ograve, trees the treatments attenuate the metabolic response to the infection. To note that in Cellina di Nard&ograve, trees at the first sampling, an increase in &gamma, aminobutyric acid (GABA) was observed. This study highlights how the infection incited by X. fastidiosa subsp. pauca strongly modifies the overall metabolism of olive trees, and how a zinc-copper-citric acid biocomplex can induce an early re-programming of the metabolic pathways in the infected trees.

In this work, we assessed the capacity of RNA polymerases to use platinated ribonucleotides as substrates for RNA synthesis by testing the incorporation of the model compound [Pt(dien)(N7-5'-GTP)] (dien=diethylenetriamine; GTP=5'-guanosine triphosphate) into a natural RNA sequence. The yield of in vitro transcription operated by T7 RNA polymerase, on the LacZ (Escherichia coli gene encoding for β-galactosidase) sequence, decreases progressively with decreasing the concentration of natural GTP, in favor of the platinated nucleotide, [Pt(dien)(N7-5'-GTP)]. Comparison of the T7 RNA polymerase transcription activities for [Pt(dien)(N7-5'-GTP)] compound incorporation reaction test, with respect to the effect of a decreasing concentration of natural GTP, showed no major differences. A specific inhibitory effect of compound [Pt(dien)(N7-5'-GTP)] (which may pair the complementary base on the DNA strand, without being incorporated in the RNA by the T7 RNA polymerase) was evidenced. Our findings therefore suggest that RNA polymerases, unlike DNA polymerases, are unable to incorporate N7-platinated nucleotides into newly synthesized nucleic acids. In this respect, specifically designed N7-platinated nucleotides based compounds could be used in alternative to the classical platinum based drugs. This approach may offer a possible strategy to target specifically DNA, without affecting RNA, and is potentially able to better modulate pharmacological activity.

The single crystal X-ray structure of the pentacoordinate complex [PtBr2(η2-CH2double bond; length as m-dashCH2)(Me2phen)], Me2phen = 2,9-dimethyl-1,10-phenanthroline, is here reported for the first time. Comparison of the complete series of [PtX2(η2-CH2double bond; length as m-dashCH2)(Me2phen)] (X = Cl, Br, I) X-ray structures shows a very low variability of the bond lengths and angles, in the trigonal equatorial plane (where η2-olefin and Me2phen are bound), on varying the coordinated axial halogens. In first approximation, this suggests describing as independents and not interacting the two subsystems constituted by the metal bonds with axial (X–Pt–X) and equatorial ligands (Me2phen–Pt–η2-ethene). This means that the electric charge donated to the metal, by the axial ligands, cannot substantially modify the bonds of the metal with the ligands in the trigonal equatorial plane. The 1H, 13C, 15N and 195Pt NMR chemical shifts variations, studied as a function of the ionic radius of the axial halides are here discussed. The NMR data strongly suggest the existence of electric pseudo-ring currents circulating around the Pt–X axes and modulated by the ionic radius of the coordinated halides.

The experiments here reported evidence on the importance of the residual charge of a nucleotide derivative, for the adsorption on nHAP (hydroxyapatite nanocrystals), in water solution. We found that the simple presence of phosphates on the nucleotide derivative does not guarantee adsorption on nHAP. On the other hand, we demonstrated that a cationic or neutral charge on a nucleotide derivative produces a strongly reduced chemical adsorption (chemisorption) whereas, in the presence of a net negative charge, relevant adsorption on nHAP is observed. The number of phosphates can only modulate the adsorption efficiency of a molecule provided that this latter bears an overall negative charge. The neutral zwitterionic nucleotide Pt(II) complexes, bearing negatively charged phosphates, are unable to give stable chemisorption. Previous considerations are important to model the binding ability of phosphate bearing nucleotide derivatives or molecules on hydroxyapatite. The findings reported in the present paper could be relevant in bone tissue targeting or nHAP mediated drug delivery.

The [PtCl(η(1)-CH2CH2OR)(Me2phen)], Me2phen = 2,9-dimethyl-1,10-phenanthroline, complex is indefinitely stable in the solid state; however, when dissolved in protic deuterated solvents at basic pH, it undergoes H-D exchange at the Me2phen Me's. An analogous H-D exchange process takes place in the related [PtCl2(Me2phen)] complex which is sterically strained and very easily can detach one nitrogen of Me2phen yielding a T-shaped species. In contrast, the H-D exchange is considerably slower in the [Pt(OR)2(Me2phen)] complex characterized by smaller size and lower trans-labilizing effect of the oxygen donor ligands. It is suggested that the formation of a T-shaped intermediate could foster the C-H activation via oxidative addition to the metal centre. In accord with this hypothesis, the H/D exchange was found to be considerably slower in analogous complexes with 6,6'-dimethyl-2,2'-bipyridyl (Me2bpy), where the greater flexibility of Me2bpy, as compared to Me2phen, reduces the strain in the four coordinate substrate and hence the propensity to dissociate one end of the bidentate ligand.

In this work we report on the synthesis of new [PtCl(η 2 -CH 2 CH 2 )( N ˆ N )] + and [PtCl(η 1 -CH 2 –CH 2 OCH 3 )( N ˆ N )] complexes, with different N ˆ N dinitrogen ligands, i.e. ethylenediamine (en), R , R - and S , S -diaminocyclohexane ( R , R - and S , S -chxn), R , R - and S , S - N , N , N′ , N′ -tetramethyl-1,2-diaminocyclohexane ( R , R - and S , S -Me 4 chxn). In particular, the factors determining complex stability are highlighted, and discussed in relation to 1 H, 13 C and 195 Pt NMR chemical shifts exhibited by different complexes bearing hindered or unhindered diamine or diimine ligands.

In this work it is described a new synthetic pathway for the synthesis of bis-cresolate Pt(II) complexes with (N-N) dinitrogen ligands. In particular, we were able, for the first time, to isolate, in the solid state, both anti-[Pt(N-N)(OC6H4-4-Me)2], N-N = 1,10-phenanthroline, (head to tail) and syn-[Pt(N-N)(OC6H4-4-Me)2], N-N = 2,2′-bipyridyl, (head to head) rotamers, which were characterized as different rotamers in the solid state by single crystal X-ray diffraction.

Synthesis and characterization of the new pentacoordinate [PtCl 2 (η 2 -C 2 H 4 )(Mebpy)] and square planar [PtCl 2 (Mebpy)] complexes both containing the asymmetrically hindered nitrogen donor chelate Mebpy = 6-Methyl-2,2′-bipyridil are reported. By nucleophilic addition of MeO − to the coordinated ethene of [PtCl 2 (η 2 -C 2 H 4 )(Mebpy)], syn -[PtCl(η 1 -CH 2 CH 2 OMe)(Mebpy)] and anti -[PtCl(η 1 -CH 2 CH 2 OMe)(Mebpy)] complexes have been obtained as the kinetic and thermodynamic product, respectively. The mechanism for selective formation of both stereoisomers is also reported. This synthetic route opens new perspectives for the stereospecific synthesis of syn - and anti -square planar organometallic complexes.