1H NMR Metabolomics on Pigs' Liver Exposed to Antibiotics Administration: An Explorative Study

An untargeted Nuclear Magnetic Resonance (NMR) spectroscopy-based metabolomics approach was applied as a first attempt to explore the metabolome of pigs treated with antibiotics. The final goal was to investigate the possibility of discriminating between antibiotic-treated (TX group) and untreated pigs (CTRL group), with the further perspective of identifying the authentication tools for antibiotic-free pork supply chains. In particular, 41 samples of pig liver were subjected to a biphasic extraction to recover both the polar and the non-polar metabolites, and the 1H NMR spectroscopy analysis was performed on the two separate extracts. Unsupervised (principal component analysis) and supervised (orthogonal partial least squares discriminant analysis) multivariate statistical analysis of 1H NMR spectra data in the range 0-9 ppm provided metabolomic fingerprinting useful for the discrimination of pig livers based on the antibiotic treatment to which they were exposed. Moreover, within the signature patterns, significant discriminating metabolites were identified among carbohydrates, choline and derivatives, amino acids and some lipid-class molecules. The encouraging findings of this exploratory study showed the feasibility of the untargeted metabolomic approach as a novel strategy in the authentication framework of pork supply chains and open a new horizon for a more in-depth investigation.

Oil and protein extraction from fruit seed and kernel by-products using a one pot enzymatic-assisted mild extraction

This research evaluated the application of a one-pot enzymatic extraction by using a protease for the concomitant and sustainable extraction of oils and proteins from fruit seeds/kernels of different species of stone, citrus and exotic fruits. The proteolysis improved the oil solvent-extractability of seeds/kernels of some fruit species compared to the use of acid and/or organic solvents and led to directly recover fat (10-33%) from mango, lemon and pumpkin seeds. Good protein extraction yields were obtained compared to conventional solvent extractions and with a good hydrolysis degree (almost 10%) in the case of lemon and pumpkin seed protein hydrolysates. The nutritional quality of all the protein hydrolysates was quite low, because of their limiting amino acids (histidine, methionine and lysine). On the contrary, the fruit seed/kernel oils resulted with high nutritional value, as they were mostly rich in unsaturated fatty acids, primarily oleic acid (>25%) and linoleic acid (till 40%).

Perenniality, more than genotypes, shapes biological and chemical rhizosphere composition of perennial wheat lines

Perennial grains provide various ecosystem services compared to the annual counterparts thanks to their extensive root system and permanent soil cover. However, little is known about the evolution and diversification of perennial grains rhizosphere and its ecological functions over time. In this study, a suite of -OMICSs - metagenomics, enzymomics, metabolomics and lipidomics - was used to compare the rhizosphere environment of four perennial wheat lines at the first and fourth year of growth in comparison with an annual durum wheat cultivar and the parental species Thinopyrum intermedium. We hypothesized that wheat perenniality has a greater role in shaping the rhizobiome composition, biomass, diversity, and activity than plant genotypes because perenniality affects the quality and quantity of C input - mainly root exudates - hence modulating the plant-microbes crosstalk. In support of this hypothesis, the continuous supply of sugars in the rhizosphere along the years created a favorable environment for microbial growth which is reflected in a higher microbial biomass and enzymatic activity. Moreover, modification in the rhizosphere metabolome and lipidome over the years led to changes in the microbial community composition favoring the coexistence of more diverse microbial taxa, increasing plant tolerance to biotic and abiotic stresses. Despite the dominance of the perenniality effect, our data underlined that the OK72 line rhizobiome distinguished from the others by the increase in abundance of Pseudomonas spp., most of which are known as potential beneficial microorganisms, identifying this line as a suitable candidate for the study and selection of new perennial wheat lines.

Protease-Assisted Mild Extraction of Soluble Fibre and Protein from Fruit By-Products: A Biorefinery Perspective

By-products from the fruit supply chain, especially seeds/kernels, have shown great potential to be valorised, due to their high content of macronutrients, such as lipids, protein, and fibre. A mild enzymatic assisted extraction (EAE) involving the use of a protease was tested to evaluate the feasibility of a cascade approach to fractionate the main fruit by-products components. Protease from Bacillus licheniformis (the enzyme used in the AOAC 991.43 official method for dietary fibre quantification) was used, and besides protein, the conditions of hydrolysis (60 °C, neutral pH, overnight) allowed us to dissolve a portion of soluble fibres, which was then separated from the solubilized peptide fraction through ethanol precipitation. Good protein extraction yields, in the range 35-93%, were obtained. The soluble fibre extraction yield ranged from 1.6% to 71% depending on the by-product, suggesting its applicability only for certain substrates, and it was found to be negatively correlated with the molecular weight of the fibre. The monosaccharide composition of the soluble fibres extracted was also diverse. Galacturonic acid was present in a low amount, indicating that pectin was not efficiently extracted. However, a predominance of arabinose and galactose monomers was detected in many fractions, indicating the isolation of a fruit soluble fibre portion with potential similarity with arabinogalactans and gum arabic, opening up perspectives for technological applications. The residual solid pellet obtained after protease assisted extraction was found to be an excellent fibre-rich substrate, suitable for being subjected to more "hard" processing (e.g., sequential pectin and hemicellulose extraction) with the objective to derive other fractions with potential great added economic value.

Dynamic changes in molecular composition of black soldier fly prepupae and derived biomasses with microbial fermentation

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Lactic fermentation was used as unconventional way to valorise black soldier fly prepupae and by-products.

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Black soldier fly biomasses (prepupae, pupuria and adult flies) were characterized before and after fermentation.

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LAB fermentation modified insect protein and lipid but not chitin fraction.

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Fermentation improved BSF biomasses in terms of unsaturated fatty acids and essential amino acids.

Black soldier fly (BSF) is being increasingly used for agro-food by-products valorisation. Adult flies, puparia, and excess of prepupae are the by-products of this process, which could be further valorised. Lactic fermentation of BSF biomasses with two different strains (L. rhamnosus and L. plantarum) has been used for this purpose.

Deep changes in the molecular composition were observed, without significant differences related to the different strains used. The lipid and protein fractions were the most impacted. Fermentation enriched the biomass in monounsaturated and polyunsaturated fatty acids and essential amino acids, significantly improving the nutritional properties of the substrates. Although not particularly marked, a proteolytic activity of lactobacilli was observed on the BSF muscular and cuticular proteins, especially in the samples of adult flies and puparia, where fermentation resulted more effective. Conversely, there was no evidence of chitinolytic activity.

Study on the Effect of Ensiling Process and Ruminal Digestion on the Synthesis and Release of Cyclopropane Fatty Acids in Cow Feeding

Cyclopropane fatty acids (CPFA) were found in milk fat from cows fed maize silage and suggested to be synthesized by lactic acid bacteria during ensiling. This study aimed to elucidate some gaps of knowledge about the microbial synthesis of CPFA, to strengthen the current authentication method based on their detection in cheese fat and performed for Parmigiano Reggiano (UNI11650), whose Specifications forbid the use of silage. CPFA were screened in different ensiled cows' feeding by gas chromatography-mass spectrometry, and the effect of feed ingredients and ruminal digestion on CPFA microbial production were further examined by in vitro tests. Results showed that solely the environmental conditions developed in silos for specific plant materials (e.g., maize) are essential for the bacterial synthesis of CPFA, whereas rumen activity did not affect CPFA levels in feeds. This supports the suitability of using CPFA as biomarkers of a crop silage-based diet forbidden by certain PDO feedstock regulations.

Cyclopropane Fatty Acids as Quality Biomarkers of Cheeses from Ewes Fed Hay- and Silage-Based Diets

This study aimed to investigate cyclopropane fatty acids (CPFAs) as quality biomarkers of forage feedings in cheese fat obtained from ewe's milk, based on two different dietary treatments (hay and silage). The gas chromatography-mass spectrometry (GC-MS) analysis detected CPFAs in most cheese samples, both from hay and silage-based diets. CPFA levels in cheese fat from hay feeding were positively correlated to the total trans-monounsaturated fatty acids (MUFAs) and n-6 polyunsaturated fatty acids (PUFAs), whereas they were negatively correlated to cis-MUFAs, odd- and branched-chain fatty acids (i.e., C13:0 anteiso, C16:0 iso, and C17:1), and C22:5n-3, which are mainly associated with a low starch intake and grass pasture. Overall, the presence of CPFAs in ovine cheese fat suggests the use of silage, but it can also be an indicator of poor-quality hay forages. This approach confirmed the reliability of CPFAs as biomarkers of forage quality, especially in relation to the use of conserved forages and good livestock practices.

Identification of Cyclopropane Fatty Acids in Human Plasma after Controlled Dietary Intake of Specific Foods

Cyclopropane fatty acids (CPFAs) are an investigated class of secondary fatty acids of microbial origin recently identified in foods. Even though the dietary daily intake of this class of compounds it has been recently estimated as not negligible, to date, no studies specifically have investigated their presence in human plasma after consumption of CPFA-rich sources. Therefore, the aims of this study were (i) to test CPFAs concentration in human plasma, thus demonstrating their in vivo bioaccessibility and potential bioavailability, (ii) to investigate a dose-response relationship between medium term chronic intake of CPFAs-rich foods and both CPFAs and plasma total fatty acid profiles in healthy subjects. Ten healthy normal weight adults were enrolled for conducting an in vivo study. Participants were asked to follow a CPFA-controlled diet for 3 weeks, consuming 50 g of Grana Padano cheese (GP) and 250 mL of whole cow milk, which correspond to a total of 22.1 mg of CPFAs. Fasting CPFAs concentration were monitored for eight timepoints during the whole study and plasma total fatty acids composition was determined by GC-MS. CPFAs, mainly dihydrosterculic acid (DHSA), were identified in plasma total fatty acids profile at the beginning of the study and after dietary treatment. A significant (p < 0.05) increase of CPFAs mean plasma concentration (n = 10) were observed at the end of the dietary intervention. Contrarily, the total fatty acids composition of the general plasma fatty acids profile did not significantly change (p ≥ 0.05) during the dietary intervention period. This is the first investigation demonstrating that CPFAs are bioaccessible in vivo and, as expected, their plasmatic concentration may be affected by consumption of CPFAs-rich foods. This research will open the door to further detailed research, which may better elucidate the role of these compounds in human health.

Determination of Cyclopropenoid Fatty Acids in Ewe Milk Fat by GC-MS after Intravenous Administration of Sterculic Acid

Cyclopropenoid fatty acids (CPEFA), found in oilseeds from Malvaceae and Sterculiaceae, have been shown to interfere with the endogenous synthesis of several bioactive lipids of dairy fat, such as cis-9, trans-11 18:2 and cis-9 18:1, by inhibiting Δ9-desaturase. No previous study has reported the presence of sterculic acid in animal fat and its incorporation in tissues after its administration, due to the lack of a proper methodology. In the present research, a GC-MS method based on cold base derivatization to fatty acids methylesters was developed to determine CPEFA in ewe milk triglycerides, after infusing sterculic acid (0.5 g/day) to six lactating ewes. An alternative derivatization based on silanyzation followed by GC-MS analysis was also tested, showing its possible applicability when CPEFA are present in the form of free fatty acids. Sterculic acid was detected in ewe milk triglycerides, demonstrating its incorporation from the bloodstream into milk by the mammary gland. The mean transfer rate represented 8.0 ± 1.0% of the daily dose. This study provides, for the first time, the presence of sterculic acid in milk fat, supporting the importance of understanding its occurrence in vivo and encouraging further research to determine whether it can be present in foods, such as dairy products, obtained under practical farming conditions.

Chemical Characterization of Capsule-Brewed Espresso Coffee Aroma from the Most Widespread Italian Brands by HS-SPME/GC-MS

Coffee capsules market is on the rise as it allows access to a wide selection of coffee, differing in taste and brand. However, few data about the chemical characterization of the capsule-brewed coffee aroma are available. In this work, an untargeted approach using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) and combined to chemometrics was performed to study and compare aroma profile from 65 capsule-brewed espresso coffees (ECs) commercialized by five of the most representative brands in Italy. Volatile profiles obtained from ECs were subjected to multivariate statistical analysis, which generally did not show a significant variability among coffees belonging to the same brand, except for those modified after the addition of specific flavor additives or aromatic substances (such as caramel, chocolate, etc.). Similarities may be related to the starting coffee brew or the processing method, which is likely the same for each individual brand. Additionally, partial least squares discriminant analysis (PLS-DA) showed that capsules from a specific brand contain the highest concentration of pyrazines, thus characterized by an intense and characteristic aroma, and a stronger note than those from the other brands. This study supports that the chemical analysis in conjunction with chemometric tools is a useful approach for assessing flavor quality, even if the need remains to identify volatile markers of high-quality beverages.

Presence of cyclopropane fatty acids in foods and estimation of dietary intake in the Italian population

Cyclopropane fatty acids (CPFAs) are the most abundant cyclic fatty acids in microorganisms with unknown role(s) regarding their dietary relevance and biological effects in humans. This work was aimed to draw up a list of CPFAs-containing foods for estimating their dietary intake in the Italian population to provide a basis for evaluating their nutritional relevance and potential health-related effects. The CPFAs content of more than 500 food items was investigated and a preliminary dietary intake was assessed (12.0 ± 6.0 mg/day), based on the data reported by the Italian National Food Consumption Survey INRAN-SCAI 2005-06. CPFAs should be considered of dietary relevance in view of their potential physiological activity in humans and their presence in significant amounts in dairy products, as Grana Padano cheese (9.0-30.0 mg/100 g), and in bovine meat (0.7-4.0 mg/100 g). Future studies should elucidate whether this uncommon class of fatty acids has a biological role in human health.

Determination of Cyclopropane Fatty Acids in Food of Animal Origin by 1H NMR

Cyclopropane fatty acids (CPFAs) are unusual fatty acids of microbial origin, recently detected in milk and dairy products. CPFAs have been demonstrated to be interesting molecular markers for authentication of dairy products obtained without ensiled feeds. Moreover, they can also be recognized as a new secondary component of human diet. Information is lacking on the presence of cyclic fatty acids in other food sources. Cyclopropane fatty acids have been detected by GC-MS analysis in cheese and other animal fats in concentration ranging from 200 to 1000 mg/kg fat, but in some cases, the complex fatty acid profile and the possible presence of interfering peaks make the separation not straightforward and the quantification uneasy. Therefore, a new reliable ¹H NMR method was developed to detect and measure CPFA content in different foods of animal origin, based on the detection of the characteristic signals of cyclopropane ring. The ¹H NMR (600 MHz) method showed detection limits comparable with those of full scan GC-MS, and it allowed the identification and quantitation of the cyclopropane fatty acids in different foods.

Development of a Quantitative GC-MS Method for the Detection of Cyclopropane Fatty Acids in Cheese as New Molecular Markers for Parmigiano Reggiano Authentication

Cyclopropane fatty acids (CPFA), as lactobacillic acid and dihydrosterculic acid, are components of bacterial membranes and have been recently detected in milk and in dairy products from cows fed with corn silage. In this paper, a specific quantitative gas chromatography-mass spectrometry (GC-MS) method for the detection of CPFA in cheeses was developed, and the quality parameters of the method (limit of detection, limit of quantitation, and intralaboratory precision) were assessed. Limit of detection and quantitation of CPFA were, respectively, 60 and 200 mg/kg of cheese fat, and the intralaboratory precision, determined on three concentration levels, satisfied the Horwitz equation. This method was applied to 304 samples of PDO cheeses of certified origin, including Parmigiano Reggiano (Italy), Grana Padano (Italy), Fontina (Italy), Comté (France), and Gruyère (Switzerland). Results showed that CPFA were absent in all of the cheeses whose Production Specification Rules expressly forbid the use of silages (Parmigiano Reggiano, Fontina, Comté, and Gruyère). CPFA were instead present in variable concentrations (300-830 mg/kg of fat) in all of the samples of Grana Padano cheese (silages admitted). A mix of grated Parmigiano Reggiano and Grana Padano was also prepared, showing that the method is able to detect the counterfeiting of Parmigiano Reggiano with other cheeses up to 10-20% Grana Padano content. These results support the hypothesis that CPFA can be used as a marker of silage feedings for cheeses, and the data reported can be considered a first attempt to create a database for CPFA presence in PDO cheeses.

Imaging in primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) accounts for approximately 3% of all primary CNS tumors. Congenital or acquired immunodeficiency is the only established risk factor for PCNSL. Rates decreased slightly in the mid-1990s, concordantly with the decreasing rates of AIDS. However, the incidence has been increasing in the elderly immunocompetent population, and this trend seems to be independent of improvements in diagnostic techniques, and of overall trends in the incidence of brain tumors and systemic lymphomas. This study presents our experience with the imaging features of PCNSL. Computed tomography (CT) and magnetic resonance imaging (MRI) findings were reviewed in a series of 38 cases of pathologically proven PCNSL. The incidence rate of PCNSL was higher in men than in women (58% versus 42%). Mean age at presentation was 63 years; 120 lesions were demonstrated in the 38 patients, with a 53% frequency of tumor multiplicity. Both CT and MR mainly showed solitary or multiple well-defined round or oval-shaped mass lesions, typically hyperdense on unenhanced CT scans, iso to hypointense on T2 MR weighted images. These lesions also showed an increased signal intensity on diffusion-weighted images. Virtually all lesions enhanced after intravenous administration of contrastmedium. On (1)H-magnetic resonance spectroscopy ((1)H-MRS) most lesions presented increased Cho/Cr, Cho/NAA and lactate/Cr ratios when compared to normal gray matter. No changes in the imaging presentation have occurred over the past two decades, apart from lesions now being smaller at diagnosis. Our imaging findings are in agreement with the existing literature data and with the reported increasing trend of multifocal tumors. Our epidemiologic results add value to the existing evidence of increasing incidence rates among the immunocompetent elderly population.