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- Volatomic pattern of breast cancer and cancer-free tissues as a powerful strategy to identify potential biomarkersPublication . Silva, Catarina; Perestrelo, Rosa; Silva, Pedro; Capelinha, Filipa; Tomás, Helena; Câmara, José S.Breast cancer (BC), ranked as the fifth amongst all cancers, remains at the top of women’s cancers worldwide followed by colorectal, lung, cervix, and stomach cancers. The main handicap of most of the screening/diagnostic methods is based on their low sensitivity and specificity and the invasive behavior of most sampling procedures. The aim of this study was to establish the volatomic pattern of BC and cancer-free (CF) tissues (n = 30) from the same patients, as a powerful tool to identify a set of volatile organic metabolite (VOM) potential BC biomarkers which might be used together or complement with the traditional BC diagnostics strategies, through the integration of chromatographic data, obtained by solid-phase microextraction followed by gas chromatography-mass spectrometry (SPME/GC-qMS), with chemometric tools. A total of four metabolites: limonene, decanoic acid, acetic acid and furfural presented the highest contribution towards discrimination of BC and CF tissues (VIP > 1, p < 0.05). The discrimination efficiency and accuracy of BC tissue metabolites was ascertained by ROC curve analysis that allowed the identification of some metabolites with high sensitivity and specificity. The results obtained with this approach suggest the possibility of identifying endogenous metabolites as a platform to find potential BC biomarkers and pave the way to investigate the related metabolomic pathways in order to improve BC diagnostic tools. Moreover, deeper investigations could unravel novel mechanistic insights into the disease pathophysiology.
- Untargeted urinary 1H NMR-based metabolomic pattern as a potential platform in breast cancer detectionPublication . Silva, Catarina L.; Olival, Ana; Perestrelo, Rosa; Silva, Pedro; Tomás, Helena; Câmara, José S.: Breast cancer (BC) remains the second leading cause of death among women worldwide. An emerging approach based on the identification of endogenous metabolites (EMs) and the establishment of the metabolomic fingerprint of biological fluids constitutes a new frontier in medical diagnostics and a promising strategy to differentiate cancer patients from healthy individuals. In this work we aimed to establish the urinary metabolomic patterns from 40 BC patients and 38 healthy controls (CTL) using proton nuclear magnetic resonance spectroscopy (1H-NMR) as a powerful approach to identify a set of BC-specific metabolites which might be employed in the diagnosis of BC. Orthogonal partial least squares-discriminant analysis (OPLS-DA) was applied to a 1H-NMR processed data matrix. Metabolomic patterns distinguished BC from CTL urine samples, suggesting a unique metabolite profile for each investigated group. A total of 10 metabolites exhibited the highest contribution towards discriminating BC patients from healthy controls (variable importance in projection (VIP) >1, p < 0.05). The discrimination efficiency and accuracy of the urinary EMs were ascertained by receiver operating characteristic curve (ROC) analysis that allowed the identification of some metabolites with the highest sensitivities and specificities to discriminate BC patients from healthy controls (e.g. creatine, glycine, trimethylamine N-oxide, and serine). The metabolomic pathway analysis indicated several metabolism pathway disruptions, including amino acid and carbohydrate metabolisms, in BC patients, namely, glycine and butanoate metabolisms. The obtained results support the high throughput potential of NMR-based urinary metabolomics patterns in discriminating BC patients from CTL. Further investigations could unravel novel mechanistic insights into disease pathophysiology, monitor disease recurrence, and predict patient response towards therapy.
- A systematic AQbD approach for optimization of the most influential experimental parameters on analysis of fish spoilage-related volatile aminesPublication . Freitas, Jorge; Silva, Pedro; Vaz-Pires, Paulo; Câmara, José S.The volatile amines trimethylamine (TMA) and dimethylamine (DMA) could be used as important spoilage indices for seafood products, assisting in the determination of the rejection period. In the present study, a systematic analytical duality-by-design (AQbD) approach was used as a powerful strategy to optimize the most important experimental parameters of headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) conditions for the quantification of TMA and DMA in Sparus aurata. This optimization enabled the selection of the best points in the method operable design region for HS-SPME extraction (30 min; 35 ◦C; NaOH 15 M and NaCl 35%, w/v) and GC-MS analysis (80 ◦C; gradient 50 ◦C/min; flow rate 1 mL/min and splitless mode). The rejection day, estimated through the TMA concentration (>12 mg/100 g, at days 9–10), was compared with sensory (quality index method: day 7–8), physical (Torrymeter: day 8–9), and microbial (day 9–10) analysis, corroborating the suitability of the proposed approach for estimating the period for which they will retain an acceptable level of eating quality from a safety and sensory perspective.
- Effect of processing and storage on the volatile profile of sugarcane honey: A four-year studyPublication . Silva, Pedro; Freitas, Jorge; Nunes, Fernando M.; Câmara, José S.Sugarcane honey (SCH) is a syrup from Madeira Island recognized by its unique and excellent aroma, associated to volatile organic compounds (VOCs) generated during the well-defined five stages of its traditional making process. The establishment of volatile profile throughout all SCH-making stages during four years, allowed the evaluation of the influence of each stage in the typical characterisitcs of SCH. One hundred eighthy seven VOCs were identified, being associated to several origins and formation pathways. VOCs formed during stage 1 and 2 were originate from raw material, and its oxidation (i.e. enzymatic browning) and thermal degradation (i.e. lipid oxidation, Maillard reactions, Strecker degradation). In stage 3 and 4, the caramelization and melanoidin degradation also occurred, while in stage 5, the thermal degradation continues, followed by microbial activity. Chemometric analysis allowed to identify 35 VOCs as potential markers for processing control by the producers and as guarantee of the typicality and authenticity of SCH. Based on the obtained results, we propose for the first time an innovative schematic diagram explaining the potential reactions and pathways for VOCs formation during the different steps of the SCH production.
- Sustainable Agricultural Systems for Fruit Orchards: The Influence of Plant Growth Promoting Bacteria on the Soil Biodiversity and Nutrient ManagementPublication . Freitas, Jorge; Silva, PedroAwareness towards the loss of soil quality as well as consumer perception about the environmental impact of agricultural activity have stimulated research and government activity toward the implementation of a sustainable agricultural system. The European Commission, in the next funding program, established specific objectives to promote the conversion towards a more environmentally sustainable agricultural system through its Green Deal Strategy. The demand for ecologically and sustainably cultivated fruits increases every year; however, suppressing such de mand is necessary to improve the production performance of orchards. The sustainable management of orchard production requires combined knowledge from different fields. The key challenge is to design orchard systems that can integrate sustainable practices, nutrient cycle knowledge and promotion of soil biodiversity. Therefore, this review compiles works that address the challenges in the implementation of a sustainable agriculture system based on Plant Growth-Promoting Bac teria (PGPB) and their impact on soil biodiversity as well as that of nutrient management on the development of fruit orchards.
- Chemical Differentiation of Sugarcane Cultivars Based on Volatile Profile and Chemometric AnalysisPublication . Silva, Pedro; Freitas, Jorge; Nunes, Fernando M.; Câmara, José S.Sugarcane (SC) is a perennial grass widely cultivated in tropical and subtropical regions. However, its cultivation in Europe is residual, where Madeira Island, Portugal, is the only region where SC continues to be extensively cultivated. For the first time, the volatile profiles of regional cultivars were established by solid-phase microextraction combined with gas chromatography− mass spectrometry. Different volatile profiles for each cultivar were recognized, identifying 260 volatile organic compounds belonging to 15 chemical classes, such as aldehydes, alcohols, ketones, hydrocarbons, esters, and terpenes. Chemometric analysis procedure, namely, one-way ANOVA with Tukey’s test, principal component analysis, partial least-square analysis, linear discriminant analysis, and hierarchical clustering analysis, allowed the differentiation between all regional cultivars. This study represents an important contribution for the maintenance of biodiversity and subsistence of the SC industry in Europe. Furthermore, it is also a valuable contribution to establish the typicality of traditional SC-based products, such as SC honey.
- Improved approach based on MALDI-TOF MS for establishment of the fish mucus protein pattern for geographic discrimination of Sparus aurataPublication . Freitas, Jorge; Silva, Pedro; Perestrelo, Rosa; Vaz-Pires, Paulo; Câmara, José S.Food fraud is still a recurrent practice throughout food supply chains. In the case of seafood, misidentification of species and products repackaging constitute the most common frauds. Therefore, the development of appropriate analytical approaches to be used against food fraud is necessary. The present study goal is to explore for the first time, the possibility to differentiate between Sparus aurata from two different mariculture farms located in Madeira Island (Caniçal and Ribeira Brava), using the mass fingerprint of fish mucus obtained from MALDI-TOF MS and analyzed using Mass-UP software for multivariate statistical analysis and biomarker identification. It was possible to establish, from the mucus protein fraction, a set of potential biomarkers for each location in a total of 35 peaks, being 17 peaks specific to Caniçal located farm and 18 to Ribeira Brava. The proposed analytical approach revealed a useful strategy providing accurate and fast results for fish geographical origin discrimination.
- Untargeted fingerprinting of cider volatiles from different geographical regions by HS-SPME/GC-MSPublication . Perestrelo, Rosa; Silva, Catarina L.; Silva, Pedro; Medina, Sonia; Pereira, Regina; Câmara, José S.The volatomic fingerprint of ciders produced in different geographical regions from Madeira Island was estab lished using headspace solid phase microextraction combined with gas chromatography mass spectrometry (HS SPME/GC–MS) in order to explore the effects of geographical region on the volatile pattern ciders in addition to identify potential molecular geographic markers. A total of 107 volatile organic compounds (VOCs) belonging to different chemical families were identified from which 50 VOCs are common to all ciders analysed. Significant differences in the relative content of VOCs from ciders of different geographical regions were observed. The potential of the identified VOCs for ciders discrimination according to region was assessed through chemometric tools, such as principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The PCA showed significant differences among ciders from different island geographical regions. Fifteen VOCs re sponsible for ciders discrimination were identified by PLS-DA. Fifteen VOCs, namely five terpenoids, four al cohols, three acids and three esters, present variable importance in projection (VIP) values higher than one. Our findings provide relevant information related to volatile signature of ciders produced in Madeira Island, which may be a useful tool to cider-making process contributing to improve the quality of the final product. In addition, the geographical discrimination recognizes the unique and distinctive characteristics that will allow in the future to protect the quality and typicity of products originating in certain geographical regions.
- A Predictive Strategy Based on Volatile Profile and Chemometric Analysis for Traceability and Authenticity of Sugarcane Honey on the Global MarketPublication . Silva, Pedro; Freitas, Jorge; Nunes, Fernando M.; Câmara, José S.Sugarcane honey (SCH) is a syrup produced on Madeira Island and recognized by its unique aroma, a complex attribute of quality with an important influence on the final consumer’s acceptance of the product, and determined by a complex mixture of a large number of volatile organic compounds (VOCs) generated during its traditional making process and storage. Therefore, the purpose of this study was to establish the volatile profile of genuine SCH produced by a regional certified producer for seven years and compare it with syrups from non-certified regional producers and with producers from different geographical regions (Spain, Egypt, Brazil and Australia), as a powerful strategy to define the volatomic fingerprint of SCH. Different volatile profiles were recognized for all samples, with 166 VOCs being identified belonging to different chemical classes, including furans, ketones, carboxylic acids, aldehydes and alcohols. Chemometric analysis allowed (i) the differentiation between all syrups, being more pronounced between SCH and other syrups; and (ii) the identification of 32 VOCs as potential markers for the traceability and authenticity of SCH on the global market.