Metabolomics for assessing safety and quality of plant-derived food

NMR fingerprinting as a tool to evaluate post-harvest time-related changes of peaches, tomatoes and plums

The time-related changes of three agricultural products, coming from two distribution routes, have been followed using NMR fingerprinting to monitor metabolic variations occurring during several days of cold storage. An NMR profiling approach was employed to evaluate the variations in metabolic profile and metabolite content in three different agricultural products highly consumed in Italy (peaches, tomatoes and plums) coming from Tuscanian farms and how they change with time after collection. For each product, we followed the time-related changes during cold storage along three different collection periods. We monitored the variations in metabolic fingerprint and the trend of a set of metabolites, focusing our attention on nutritive and health-promoting metabolites (mainly, essential amino acids and antioxidants) as well as metabolites that contribute to the taste. Concurrently, for comparison, the time-dependent changes of the same kind of products coming from large-scale distribution have been also analyzed under the same conditions. In this second category, only slight variations in the metabolic fingerprint and metabolite levels were seen during cold storage. Unsupervised and supervised multivariate statistics was also employed to enlighten the differences between the three collections. In particular it seems that the metabolic fingerprint of large-scale distribution products is quite similar in the early, middle and late collection, while peaches and plums locally collected are markedly different among the three periods. The metabolic profiles of the agricultural products belonging to these two different distribution routes are intrinsically different, and they show different changes during the time of cold storage.

Genetic basis and detection of unintended effects in genetically modified crop plants

In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled “Genetic Basis of Unintended Effects in Modified Plants” was held in Ottawa, Canada, bringing together over 75 scientists from academia, government, and the agro-biotech industry. The objectives of the meeting were to explore current knowledge and identify areas requiring further study on unintended effects in plants and to discuss how this information can inform and improve genetically modified (GM) crop risk assessments. The meeting featured presentations on the molecular basis of plant genome variability in general, unintended changes at the molecular and phenotypic levels, and the development and use of hypothesis-driven evaluations of unintended effects in assessing conventional and GM crops. The development and role of emerging “omics” technologies in the assessment of unintended effects was also discussed. Several themes recurred in a number of talks; for example, a common observation was that no system for genetic modification, including conventional methods of plant breeding, is without unintended effects. Another common observation was that “unintended” does not necessarily mean “harmful”. This paper summarizes key points from the information presented at the meeting to provide readers with current viewpoints on these topics.

Composition of nonanthocyanin polyphenols in alcoholic-fermented strawberry products using LC-MS (QTRAP), high-resolution MS (UHPLC-Orbitrap-MS), LC-DAD, and antioxidant activity

In this study, the nonanthocyanin (poly)phenolic profile of an alcoholic-fermented strawberry beverage was characterized. High-performance liquid chromatography coupled with a triple-quadropole mass spectrometer and ultra-high-performance liquid chromatography coupled with a linear trap quadropole and an Orbitrap mass analyzer was used to identify nonanthocyanin phenolic compounds. Sixty-six compounds were identified, and 13 of these were identified for the first time in strawberry or its derived alcoholic fermented beverage: protocatechuic acid-4-O-β-hexoside, brevifolin carboxylic acid, ferulic acid glucuronide, dimer caffeic acid-O-hexoside, luteolin-3'-O-xyloside, isorhamnetin 3-O-glucoside, taxifolin-O-glucoside, (+)-aromadendrin rhamnoside, eriodictyol-7-O-glucoside, (+)-taxifolin, (+)-aromadendrin, eriodictyol, and homovanillic acid. The alcoholic fermentation process produced significant increases in certain compounds, such as homovanillic acid and p-hydroxybenzoic acid, while a significant decrease in galloyl bis-HHDP-glucose was observed. Linear discriminant analysis correctly classified samples initial, final, and pasteurized, which led to the conclusion that alcoholic fermentation induces significant changes in composition, mainly in relation to the 19 compounds represented in the tables of this work.

Evaluation of saffron (Crocus sativus L.) adulteration with plant adulterants by (1)H NMR metabolite fingerprinting

In the present work, a preliminary study for the detection of adulterated saffron and the identification of the adulterant used by means of (1)H NMR and chemometrics is reported. Authentic Greek saffron and four typical plant-derived materials utilised as bulking agents in saffron, i.e., Crocus sativus stamens, safflower, turmeric, and gardenia were investigated. A two-step approach, relied on the application of both OPLS-DA and O2PLS-DA models to the (1)H NMR data, was adopted to perform authentication and prediction of authentic and adulterated saffron. Taking into account the deficiency of established methodologies to detect saffron adulteration with plant adulterants, the method developed resulted reliable in assessing the type of adulteration and could be viable for dealing with extensive saffron frauds at a minimum level of 20% (w/w).

¹H NMR Spectroscopy and Multivariate Analysis of Monovarietal EVOOs as a Tool for Modulating Coratina-Based Blends

Coratina cultivar-based olives are very common among 100% Italian extra virgin olive oils (EVOOs). Often, the very spicy character of this cultivar, mostly due to the high polyphenols concentration, requires blending with other “sweetener” oils. In this work, monovarietal EVOO samples from the Coratina cultivar (Apulia, Italy) were investigated and compared with monovarietal EVOO from native or recently introduced Apulian (Italy) cultivars (Ogliarola Garganica, Ogliarola Barese, Cima di Mola, Peranzana, Picholine), from Calabria (Italy) (Carolea and Rossanese) and from other Mediterranean countries, such as Spain (Picual) and Greece (Kalamata and Koroneiki) by ¹H NMR spectroscopy and multivariate analysis (principal component analysis (PCA)). In this regard, NMR signals could allow a first qualitative evaluation of the chemical composition of EVOO and, in particular, of its minor component content (phenols and aldehydes), an intrinsic behavior of EVOO taste, related to the cultivar and geographical origins. Moreover, this study offers an opportunity to address blended EVOOs tastes by using oils from a specific region or country of origin.