1H-NMR-based metabolomic profiles of different sweet melon (Cucumis melo L.) Salento varieties: Analysis and comparison

1H-NMR-Based Metabolomic Profiles of Zucchini (Cucurbita pepo L.) Grown with Different Agricultural Practices for Sustainable Crop Production

Zucchini (Cucurbita pepo subsp. pepo) is a seasonal vegetable (also known as courgette) characterized by health properties due to the content of several bioactive molecules. For this reason, the consumption of zucchini is highly recommended as a part of the Mediterranean diet. The aim of this study was to evaluate the possible influence of a specific compost supply for shifting the characteristics of an integrated agriculture toward a biodynamic standard following Demeter® certified rules. In particular, an approach based on 1H-Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate statistical analysis (MVA) was applied to analyze the differences between the metabolic profiles of the zucchini samples (with the same cultivar, Vitulia), obtained from three different agronomical practices: two focused agricultural systems (compost supplied and integrated), as well as the used benchmark (Demeter biodynamic certified). The obtained results showed that the samples from the plots managed with biofertilizer from compost showed similar behaviour to the samples managed under Demeter biodynamic certification, with higher content of some amino acids, such as arginine, and lower content of sugars than the samples from integrated farming. The concentration of twenty elements was then determined using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The averaged results of the elemental data appear almost parallel to the trend observed with the metabolomics approach. In the present case, the use of a specific compost as a biofertilizer has shown to promote the transition to the quality standards of the Demeter certification, significantly improving the crops' sustainability.

Effects of a feed supplement, containing undenatured type II collagen (UC II®) and Boswellia Serrata, in the management of mild/moderate mobility disorders in dogs: A randomized, double-blind, placebo controlled, cross-over study

This study was designed as a randomized, placebo-controlled, double-blinded, cross-over trial performed to investigate the effects of a dietary supplement containing undenatured type II collagen (UCII®) and Boswellia Serrata on mobility, pain and joint metabolism in mild moderate osteoarthritis (OA) in dogs. A total of 60 dogs with mobility problems were evaluated and enrolled in the study. Seventeen of these dogs with mild/moderate OA were randomized to receive the product A (UCII® + Boswellia Serrata supplement-UCII®-BW) or product B (Placebo -PL), 1 chew per day for 8 weeks by oral route, and repeated in a crossover design after 4 weeks of washout period. All the subjects had veterinary evaluations during the trial and owners were requested to fill out a questionnaire on mobility impairment using the Liverpool Osteoarthritis in dogs scale (L.O.A.D.) at each time of the study. Objective tools were used to assess mobility, activity, and pain. Metabolomic analysis was performed on synovial fluid of most affected joint at the beginning and the end of the study. The results proved that UCII®+Boswellia serrata supplemented group over a period of eight weeks results in an improvement of mobility impairment, already at 4 weeks of administration, according to the owner´s evaluation. In contrast, its absence increased the risk of OA crisis and decreased the pain threshold on the most affected joint. Furthermore, the synovial fluid metabolic profile showed moderate differences between the beginning and the end of the supplementation period, with a particular influence associated to the time of UCII®-BW administration.

Metabolomics applications for plant-based foods origin tracing, cultivars identification and processing: Feasibility and future aspects

Metabolomics, the systematic study of metabolites, is dedicated to a comprehensive analysis of all aspects of plant-based food research and plays a pivotal role in the nutritional composition and quality control of plant-based foods. The diverse chemical compositions of plant-based foods lead to variations in sensory characteristics and nutritional value. This review explores the application of the metabolomics method to plant-based food origin tracing, cultivar identification, and processing methods. It also addresses the challenges encountered and outlines future directions. Typically, when combined with other omics or techniques, synergistic and complementary information is uncovered, enhancing the classification and prediction capabilities of models. Future research should aim to evaluate all factors affecting food quality comprehensively, and this necessitates advanced research into influence mechanisms, metabolic pathways, and gene expression.

Quantification of cucurbitacin E in different varieties of melon (Cucumis melo L.) fruit through validated RP-HPLC method

The different varieties of melons (Cucumis melo L.) have been used in various traditional systems of medicine for decades to treat different ailments, including inflammation, cancer, cardiovascular, diabetes, edema, etc. The present study was designed for the quantification of cucurbitacin E in five different varieties of melon fruit through a validated RP-HPLC method. A solvent system is being optimized with a 70:30 (v/v) ratio of acetonitrile: water (1% glacial acetic acid) at a 1 mL/min flow rate and scanning spectrum (λmax) of 230 nm. A calibration curve for standard cucurbitacin E was generated and found to be linear (1-100 µg/mL). The variation of cucurbitacin E content among five different varieties of melon fruits is 0.0129% w/w- 0.231% w/w. This precise and reproducible method may be beneficial in addressing the quality-related aspects of medicinal food plants of Cucurbitaceae and its derived products or formulations.

Editorial for the Special Issue "NMR- and MS-Based Metabolomics Approaches for Local and Traditional Foods' Characterization"

Metabolomics is a powerful tool in food sciences, widely used in food analysis for authenticity and traceability assessment and regulatory compliance, processing, quality, and safety [...].

Metabolomic NMR analysis and organoleptic perceptions of pomegranate wines: Influence of cultivar and yeast on the product characteristics

Pomegranate (Punica granatum L.) fruits are a historical agricultural product of the Mediterranean basin that became increasingly popular in the latest years for being rich in antioxidants and other micronutrients, and are extensively commercialized as fruits, juice, jams and, in some Eastern countries, as a fermented alcoholic beverage. In this work, four different pomegranate wines specifically designed using combinations of two cultivars (Jolly Red and Smith) and two yeast starters with markedly different characteristics (Saccharomyces cerevisiae Clos and Saccharomyces cerevisiae ex-bayanus EC1118) were analyzed. The chemical characterization of the wines together with the originating unfermented juices was performed by ¹H NMR spectroscopy metabolomic analysis. The full spectra were used for unsupervised and supervised statistical multivariate analysis (MVA), namely Principal Component Analysis (PCA), Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), and sparse PCA (SPCA). The MVA of the wines showed a clear discrimination between the cultivars, and a smaller, yet significant, discrimination between the yeasts used. In particular, a higher content of citrate and gallate was observed for the Smith cv. and, on the contrary, a statistically significant higher content of fructose, malate, glycerol, 2,3 butanediol, trigonelline, aromatic amino acids and 4-hydrophenylacetate was observed in Jolly Red pomegranate wines samples. Significant interaction among the pomegranate cultivar and the fermenting yeast was also observed. Sensorial analysis was performed by a panel of testing experts. MVA of tasting data showed that the cultivar significantly affected the organoleptic parameters considered, while the yeast had a minor impact. Correlation analysis between NMR-detected metabolites and organoleptic descriptors identified several potential sensorially-active molecules as those significantly impacting the characteristics of the pomegranate wines.

Anti-urolithiatic effect of Cucumis melo L. var inodorous in male rats with kidney stones

Melon seed extracts have high antioxidant activities and are effective against a variety of diseases, including kidney stones. In kidney stone model rats, the anti-urolithiatic effects of the hydro-ethanolic extract of melon seed and potassium citrate were studied and compared. After urolithiasis induction by ethylene glycol, the extract and potassium citrate were treated orally for 38 days concurrent with ethylene glycol. Then, urine and kidney sampling were done, and the urinary parameter levels were measured. The melon and potassium citrate treatments reduced the kidney index, the levels of urinary calcium and oxalate, calcium oxalate deposit numbers, the score of crystal deposits, histo-pathological damages, and the score of inflammation in the kidney sections, while elevating the urinary pH, magnesium, and citrate levels, and also the expression of the UMOD, spp1, and reg1 genes in the kidney of treated animals. The effect of potassium citrate is the same as the effect of melon in treated animals. So, their effects could be by normalizing urinary parameters, reducing crystal deposits, excreting small deposits from the kidney, reducing the chance of them being retained in the urinary tract, and elevating the expression of the UMOD, spp1, and reg1 genes, which are involved in kidney stone formation.

1H NMR-based metabolic profile and chemometric analysis for the discrimination of Passiflora species genotypic variations

The species of the genus Passiflora (Passifloraceae family) have been used as food, cosmetic and traditional herbal. As a result, the Passiflora species are widely cultivated and has an economic, medicinal and ornamental importance. The popular designation as "passion fruit" and chemical profile of several Passiflora species remains unknown. The lack of chemical information contributes to the erroneous classification and adulteration. In recent years, special attention has been paid to the bioactivity and phytochemical profiles of several Passiflora species extracts. In this research, ¹H NMR-based metabolic profiling coupled with chemometric tools was used to characterize and distinguish extracts obtained from different wild Passiflora species (P. alata, P. cincinnata, and P. setacea) and genetic varieties (P. alata var. BRS Pérola do Cerrado, P. cincinnata var. BRS Sertão Forte, and P. setacea var. BRS Pérola do Cerrado). Fourteen metabolites were identified by 1D and 2D NMR experiments, highlighting the presence of fatty acids, carbohydrates, saponins, alkaloids, and mainly C-glycosidic flavones. Principal components analysis (PCA) allowed discrimination of Passiflora extracts, which the quadranguloside, oleanolic acid-3-sophoroside, α-glucose, β-glucose, and vitexin-2-O"-rhamnoside were relevant in the differentiation of P. alata and P. alata var. BRS Pérola do Cerrado, while the flavones isovitexin and isovitexin-2-O"-xyloside were dominant in the grouping of P. setacea and P. setacea var. BRS Pérola do Cerrado, and finally P. cincinnata and P. cincinnata var. BRS Sertão Forte grouped by the influence of the fatty acids, sucrose, flavones (isoorientin and vitexin-2-O"-xyloside), and trigonelline. The varieties of P. setacea, and P. cincinnata are chemically equivalent to the original Passiflora species. However, the PCA analysis showed that the genetic variety of P. alata occupied a different position in the scores plot provoked mainly by the presence of oleanolic acid-3-sophoroside. The ¹H NMR metabolic profile can be efficient for quality control evaluation, and can contribute to the investigation of new alternatives for official Passiflora herbal medicines.

1H-NMR metabolomic profile of healthy and osteoarthritic canine synovial fluid before and after UC-II supplementation

The aim of the study was to compare the metabolomic synovial fluid (SF) profile of dogs affected by spontaneous osteoarthritis (OA) and supplemented with undenatured type II collagen (UC-II), with that of healthy control dogs. Client-owned dogs were enrolled in the study and randomized in two different groups, based on the presence/absence of OA (OA group and OA-free group). All dogs were clinically evaluated and underwent SF sampling for ¹H-Nuclear Magnetic Resonance spectroscopy (¹H-NMR) analysis at time of presentation. All dogs included in OA group were supplemented with UC-II orally administered for 30 days. After this period, they were reassessed (OA-T30). The differences in the ¹H-NMR metabolic SFs profiles between groups (OA-free, OA-T0 and OA-T30) were studied. The multivariate statistical analysis performed on SFs under different conditions (OA-T0 vs OA-T30 SFs; OA-T0 vs OA-free SFs and OA-T30 vs OA-free SFs) gave models with excellent goodness of fit and predictive parameters, revealed by a marked separation between groups. β-Hydroxybutyrate was identified as a characteristic compound of osteoarthritic joints, showing the important role of fat metabolism during OA. The absence of β-hydroxybutyrate after UC-II supplementation suggests the supplement's effectiveness in rebalancing the metabolism inside the joint. The unexpectedly high level of lactate in the OA-free group suggests that lactate could not be considered a good marker for OA. These results prove that ¹H-NMR-based metabolomic analysis is a valid tool to study and monitor OA and that UC-II improves clinical symptoms and the SF metabolic profile in OA dogs.

Classification of Prunus Genus by Botanical Origin and Harvest Year Based on Carbohydrates Profile

The 1H-NMR carbohydrates profiling was used to discriminate fruits from Rosaceae family in terms of botanical origin and harvest year. The classification was possible by application of multivariate data analysis, such as principal component analysis (PCA), linear discriminant analysis (LDA) and Pearson analysis. Prior, a heat map was created based on 1H-NMR signals which offered an overview of the content of individual carbohydrates in plum, apricot, cherry and sour cherry, highlighting the similarities. Although, the PCA results were almost satisfactory, based only on carbohydrates signals, the LDA reached 94.39% and 100% classification of fruits according to their botanical origin and growing season, respectively. Additionally, a potential association with the relevant climatic data was explored by applying the Pearson analysis. These findings are intended to create an efficient NMR-based solution capable of differentiating fruit juices based on their basic sugar profile.

Nutraceutical Profile of "Carosello" (Cucumis melo L.) Grown in an Out-of-Season Cycle under LEDs

The world population is projected to increase to 9.9 billion by 2050 and, to ensure food security and quality, agriculture must sustainably multiply production, increase the nutritional value of fruit and vegetables, and preserve genetic variability. In this work, an Apulian landrace of Cucumis melo L. called "Carosello leccese" was grown in a greenhouse with a soilless technique under light-emitting diodes (LEDs) used as supplementary light system. The obtained results showed that "Carosello leccese" contains up to 71.0 mg·g-1 dried weight (DW) of potassium and several bioactive compounds important for human health such as methyl gallate (35.58 µg·g-1 DW), α-tocopherol (10.12 µg·g-1 DW), and β-carotene (up to 9.29 µg·g-1 DW under LEDs). In fact, methyl gallate has antioxidative and antiviral effects in vitro and in vivo, tocopherols are well recognized for their effective inhibition of lipid oxidation in foods and biological systems and carotenoids are known to be very efficient physical and chemical quenchers of singlet oxygen. Finally, it was demonstrated that the LEDs' supplementary light did not negatively influence the biochemical profile of the peponids, confirming that it can be considered a valid technique to enhance horticultural production without reducing the content of the bioactive compounds of the fruits.

NMR Metabolome-Based Classification of Cymbopogon Species: a Prospect for Phyto-equivalency of its Different Accessions Using Chemometric Tools

Cymbopogon species are widely distributed worldwide and known for their high essential oil content with potential commercial and medicinal benefits justifying for their inclusion in food and cosmetics. Most species received scant characterization regarding their full complement of bioactive constituents necessary to explain their medicinal activities. In this study, the metabolite profiles of 5 Cymbopogon species, C. citratus, C. flexuosus, C. procerus, C. martini, and C. nardus, were characterized via NMR-based metabolomics. The results of 13 shoot accessions revealed the identification and quantification of 23 primary and secondary metabolites belonging to various compound classes. Multivariate analyses were used for species classification, though found not successful in discrimination based on geographical origin. Nevertheless, C. citratus was found particularly enriched in neral, geranial, (E)-aconitic acid, isoorientin, and caffeic acid as the major characterizing metabolites compared to other species, while an unknown apigenin derivative appeared to discriminate C. martini. The high essential oil and phenolic content in C. citratus emphasizes its strong antioxidant activity, whereas (E)-aconitic acid accounts for its traditional use as insecticide. This study affords the first insight into metabolite compositional differences among Cymbopogon species. Moreover, antimicrobial, insecticidal, antidiabetic, and antioxidant compounds were identified that can be utilized as biomarkers for species authentication.

Evaluation of ORAC, IR and NMR metabolomics for predicting ripening stage and variety in melon (Cucumis melo L.)

A combination of FTIR- and NMR-based metabolomics approaches coupled to multivariate data analysis techniques was used for the first time to characterize and explore the metabolic changes along the ripening of two Spanish melon landraces (Jimbee N and Jimbee XL). Furthermore, the fatty acids profile and the antioxidant capacity were investigated by GC-FID and ORAC method, respectively. Despite FTIR was able to identify changes in the sugars content between fruits of different maturity stages, it failed to discriminate between both varieties, being exceeded by NMR in both situations. Increased fruit maturation led to an increase of sucrose, fatty acids and β-carotene, accompanied by a decrease of glucose, fructose, citrate, amino acids, and polyphenols (which were positively correlated with fruits antioxidant activity).

NMR Tracing of Food Geographical Origin: The Impact of Seasonality, Cultivar and Production Year on Data Analysis

The traceability of typical foodstuffs is necessary to protect high quality of traditional products. It is well-known that several factors could influence metabolites content in certified foods, but soil composition, altitude, latitude and coded production protocols constitute the territorial conditions responsible for the peculiar organoleptic and nutritional properties of labelled foods. Instead, regardless of origin, seasonality, cultivar, collection year can affect all agricultural products, so it is appropriate to include them in data analysis in order to obtain a correct interpretation of the differences linked to growing areas alone. Therefore, it is useful to use a flexible all-round technique, and NMR spectroscopy coupled with multivariate statistical analysis is considered a powerful means of assessing food authenticity. The purpose of this review is to investigate the relevance of year, cultivar, and seasonal period in the determination of food geographical origin using NMR spectroscopy. The strategy for testing these three factors may differ from author to author, but a preliminary study of cultivar or collection year effects on NMR spectra is the most popular method before starting the geographical characterization of samples. In summary, based on the available literature, the most significant influence is due to cultivar, followed by harvesting year, however seasonality is not considered a source of variability in data analysis.

Classical Food Quality Attributes and the Metabolic Profile of Cambuci, a Native Brazilian Atlantic Rainforest Fruit

The cambuci is a native Brazilian fruit from the Atlantic Forest biome. A soft and astringent pulp, a green color, and a sweet aroma are its main characteristics. Classical food quality attributes (fresh fruit mass, fruit height, diameters, total soluble solid, titratable acidity, and ratio) and the metabolic profile from ten accessions from three different locations were analyzed herein by analytical methods (refractometry and neutralization titration) and nuclear magnetic resonance spectroscopy. Concerning sugar content, sucrose was the predominant compound, with glucose and fructose alternating in second, depending on the accession. Citric acid was the most relevant acid, followed by shikimic and quinic acids in quite variable amounts. These three main acids vary in amounts for each accession. Ascorbic acid content emerges as an important quality attribute and makes this fruit nutritionally attractive, due to values comparable to those contained in citric fruits. The main amino acids identified in cambuci were glutamic acid individually or in comprising the tripeptide glutathione (glutamic acid, cysteine, glycine). The quality diversity of the evaluated accessions suggests the potentiality of cambuci use in future breeding programs.

First Insight into Nutraceutical Properties of Local Salento Cichorium intybus Varieties: NMR-Based Metabolomic Approach

BACKGROUND

Plants of genus Cichorium are known for their therapeutic and nutraceutical properties determined by a wealth of phytochemical substances contained in the whole plant. The aim of this paper was to characterize the metabolic profiles of local Salento chicory (Cichorium intybus L.) varieties ("Bianca", "Galatina", "Leccese", and "Otranto") in order to describe their metabolites composition together with possible bioactivity and health beneficial properties.

METHODS

The investigation was performed by 1H-NMR spectroscopy and Multivariate Analysis (MVA), by which the metabolic profiles of the samples were easily obtained and compared.

RESULTS

The supervised Partial Least Squares Discriminant Analysis (PLS-DA) analysis showed as "Bianca" and "Galatina" samples grouped together separated by "Leccese" and "Otranto" varieties. A different content of free amino acids and organic acids was observed among the varieties. In particular a high content of cichoric and monocaffeoyl tartaric acid was observed for the "Leccese" variety. The presence of secondary metabolites adds significant interest in the investigation of Cichorium inthybus, as this vegetable may benefit human health when incorporated into the diet.

CONCLUSIONS

The 1H-NMR (Nuclear Magnetic Resonance Spectroscopy) based characterization of Salento chicory varieties allowed us to determine the potential usefulness and nutraceutical properties of the product, also providing a method to guarantee its authenticity on a molecular scale.

NMR-Based Plant Metabolomics in Nutraceutical Research: An Overview

Few topics are able to channel the interest of researchers, the public, and industries, like nutraceuticals. The ever-increasing demand of new compounds or new sources of known active compounds, along with the need of a better knowledge about their effectiveness, mode of action, safety, etc., led to a significant effort towards the development of analytical approaches able to answer the many questions related to this topic. Therefore, the application of cutting edges approaches to this area has been observed. Among these approaches, metabolomics is a key player. Herewith, the applications of NMR-based metabolomics to nutraceutical research are discussed: after a brief overview of the analytical workflow, the use of NMR-based metabolomics to the search for new compounds or new sources of known nutraceuticals are reviewed. Then, possible applications for quality control and nutraceutical optimization are suggested. Finally, the use of NMR-based metabolomics to study the impact of nutraceuticals on human metabolism is discussed.

1H NMR Metabolic Profile of Scyphomedusa Rhizostoma pulmo (Scyphozoa, Cnidaria) in Female Gonads and Somatic Tissues: Preliminary Results

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 ω-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.

Amino Acid Profile of Fruits as Potential Fingerprints of Varietal Origin

This study aims to assess the capability of the ¹H-NMR profiling of fruits from different genera in combination with multivariate data analysis to provide feasible information for fruit juices’ authenticity in terms of botanical origin. Nine fruit varieties from four genera were selected for the experimental plan. The juice obtained from the fruits was characterized using the ¹H-NMR technique, selecting the obtained amino acid profile of fruits as a potential specific fingerprint. Due to the complex information provided by the NMR spectra, a chemometric approach of the data was further applied to enable the differentiation of the fruit samples, highlighting thus its suitability as a discrimination tool for the varietal origin. The advantage of this analytical approach is given by the relatively simple working procedure, which consists of an easy, fast, and accessible preparation stage while providing complex information on fruit composition.

Revealing the 1H NMR metabolome of mirasol chili peppers (Capsicum annuum) infected by Candidatus Phytoplasma trifolii

The infection of Capsicum annuum cv. mirasol by Candidatus Phytoplasma trifolii (16SrVI) causes devastating crop losses in northern Mexico. This study addresses the metabolomics profiling of mirasol chili peppers (Capsicum annuum cv. mirasol) infected by Candidatus Phytoplasma trifolii. For this study, 25 diseased fruits and 25 healthy fruits were used. Principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) revealed dramatic changes in the content of 42 metabolites which were identified in diseased and healthy mirasol chili peppers. The endogenous levels of fructose, glucose and formic acid were substantially decreased in the diseased chili peppers. In the same group of samples, high concentrations of alanine, asparagine, fumaric acid, sucrose and threonine were observed. The content of Choline didńt present a significant difference. This evidence supports the fact that Candidatus Phytoplasma trifolii infection reduces de CO₂ fixation into carbohydrates, decreases invertase activity, and inhibits glycolysis in the diseased plant tissues. The levels of ascorbic acid, capsaicin and dihydrocapsaicinin in diseased fruits were dramatically decreased, suggesting that Candidatus Phytoplasma trifolii can reduce the pungency and the nutraceutical value of mirasol chili peppers.

The response of the algae Fucus virsoides (Fucales, Ochrophyta) to Roundup® solution exposure: A metabolomics approach

Glyphosate, as a broad-spectrum herbicide, is frequently detected in water and several studies have investigated its effects on several freshwater aquatic organisms. Yet, only few investigations have been performed on marine macroalgae. Here, we studied both the metabolomics responses and the effect on primary production in the endemic brown algae Fucus virsoides exposed to different concentration (0, 0.5, 1.5 and 2.5 mg L-1) of a commercial glyphosate-based herbicide, namely Roundup®. Our results show that Roundup® significantly reduced quantum yield of photosynthesis (Fv/Fm) and caused alteration in the metabolomic profiles of exposed thalli compared to controls. Together with the decrease in the aromatic amino acids (phenylalanine and tyrosine), an increase in shikimate content was detected. The branched-amino acids differently varied according to levels of herbicide exposure, as well as observed for the content of choline, formate, glucose, malonate and fumarate. Our results suggest that marine primary producers could be largely affected by the agricultural land use, this asking for further studies addressing the ecosystem-level effects of glyphosate-based herbicides in coastal waters.

1H-NMR Metabolite Fingerprinting Analysis Reveals a Disease Biomarker and a Field Treatment Response in Xylella fastidiosa subsp. pauca-Infected Olive Trees

Xylella fastidiosa subsp. pauca is a xylem-limited bacterial phytopathogen currently found associated on many hectares with the "olive quick decline syndrome" in the Apulia region (Southern Italy), and the cultivars Ogliarola salentina and Cellina di Nardò 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®, 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 Nardò 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®-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®, 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 Nardò trees the treatments attenuate the metabolic response to the infection. To note that in Cellina di Nardò trees at the first sampling, an increase in γ-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.

¹H NMR Spectroscopy and MVA to Evaluate the Effects of Caulerpin-Based Diet on Diplodus sargus Lipid Profiles

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 ω3 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.