Effect of geographical location, processing and simulated digestion on antioxidant characteristics of quince (Cydonia oblonga).

Quince fruit (Cydonia oblonga Miller) is an important source of bioactive compounds, especially of phenolic compounds, that's why it is considered a good source of antioxidants. However, it is known that the antioxidant characteristics and the beneficial effect of foods are affected by the variety, geographical origin, processing and gastrointestinal digestion. In this work, the effects of the geographical origin, processing, and simulated digestion of quince jam on its antioxidant characteristics were studied. Phenolic composition and antioxidant capacity were determined in quince fruit and jam from four different locations in San Juan, Argentina. The results showed that quince fruit samples from St. Lucia had the highest total phenolic content (5.13 mg GAE/g; p < 0.05) and in vitro antioxidant capacity measured by ferric-reducing antioxidant power assay (FRAP) and radical-scavenging capacity assay (DPPH· and ABTS·+ ). With regard to quince jam, a positive effect was observed on its antioxidant characteristics after processing. Twenty-one phenolics were detected in jam, being most of them derivatives of hydroxycinnamic acids (eg. 5-caffeoylquinic acid; 4-caffeoylquinic acid and quinic acid). Studies on stability and bioaccessibility of quince phenolics showed that less than 25% of the initial phenolics in jam were detected after digestion being quinic acid and hydroxycinnamic acids the most resistant. The in vitro antioxidant capacity showed, in general, a similar trend to the phenolics content throughout the digestion process. The results obtained showed that the antioxidant activity of quince and jam is related to the type and amount of phenolics in the samples, which depends on the geographical origin, processing, and gastrointestinal digestion. These variables are not always taken into account when studying the probable antioxidant activity of food, even though they should be considered for a complete nutritional evaluation of a food.

Novel cookie formulation with defatted sesame flour: Evaluation of its technological and sensory properties. Changes in phenolic profile, antioxidant activity, and gut microbiota after simulated gastrointestinal digestion.

Defatted sesame flour (DSF), a coproduct of the sesame oil extraction process, is often discarded despite having high polyphenol content. The aim of this study was to improve the antioxidant properties of cookies with increasing amounts of DSF (5, 10, and 20%) and study its impact on processing and gastrointestinal digestion. Besides, we evaluated the effect of this incorporation on the technological and sensory properties of cookies. The formulation with 10% (SFC10) showed technological quality similar to control, and was the most accepted by consumers. After baking, 13 out of 25 polyphenols from DSF were observed, and only 19% of the initial SFC10 polyphenols would be potentially absorbed after digestion. Besides, the addition of DSF benefits the microbiota composition after colonic fermentation. In conclusion, supplementation with 10% of DSF in cookies improves sensorial acceptance and antioxidant properties, without affecting the technological ones.

Identification of chia, flax and sesame seeds authenticity markers by NMR-based untargeted metabolomics and their validation in bakery products containing them.

Chia, flax, and sesame seeds are considered superseeds due to their beneficial nutritional properties, and they are frequently included as functional ingredients in foods. Authenticity markers of these seeds, including bakery products containing them, have been identified by both liquid and gas chromatography coupled to mass spectrometry (LC-MS/MS and GC-MS/MS, respectively) targeted metabolomics. However, there are no reports describing the use of nuclear magnetic resonance (NMR) spectroscopy based metabolomics to identify authenticity markers in either the raw seeds or foods containing them. We herein report the application of an untargeted NMR-based metabolomics workflow to the identification of authenticity markers for the three seeds. Seven markers, belonging to the families of polyphenols and cyanogenic glycosides, allowed good differentiation of the raw materials. Validation in cookies containing different seed percentages showed that two markers resisted the processing stage, making them feasible authenticity markers for the food trade.

Impact of storage on the functional characteristics of a fermented cereal product with probiotic potential, containing fruits and phytosterols.

The aim of this work was to study the changes in the functional characteristics of a fermented maize product containing fruits, and enriched with phytosterols. Functional characteristics (natural antioxidants and phytosterols content, in vitro antioxidant capacity and probiotic viability), lipid oxidation, and physicochemical parameters were investigated during 4 weeks of storage at 4 °C. The differences between one formulation elaborated with semi-skimmed powdered milk (Basic Product) and another with whey protein isolate (WPI Product) were evaluated. The content of polyphenols, carotenoids and tocopherols remained unchanged during the storage of both formulations. These compounds increased the antioxidant capacity in both products compared to the control formulation (without fruits), which was displayed along the whole storage period. The doses of phytosterols and the probiotic potential were maintained to the end of the storage period for both formulations. Basic and WPI products represent novel foods with desirable functional characteristics preserved during commercial storage.

Comparative metabolite fingerprinting of chia, flax and sesame seeds using LC-MS untargeted metabolomics.

Chia, flax, and sesame seeds are well known for their nutritional quality and are commonly included in bakery products. So far, the development of methods to verify their presence and authenticity in foods is a requisite and a raised need. In this work we applied untargeted metabolomics to propose authenticity markers. Seeds were analyzed by HPLC-MS/MS and 9938 features in negative mode and 9044 in positive mode were obtained by Mzmine. After isotopes grouping, alignment, gap-filling, filtering adducts, and normalization, PCA was applied to explore the dataset and recognize pre-existent classification patterns. OPLS-DA analysis and S-Plots were used as supervised methods. Twenty-five molecules (12 in negative mode and 13 in positive mode) were selected as discriminant for the three seeds, polyphenols and lignans were identified among them. To the best of our knowledge, this is the first approach using non-target HPLC-MS/MS for the authentication of chia, flax and sesame seeds.

Trophic transfer of emerging metallic contaminants in a neotropical mangrove ecosystem food web.

Emerging metallic contaminants (EMCs) are of concern due their presence in aquatic ecosystems and the lack of environmental regulations in several countries. This study verifies the presence of EMCs in two neotropical mangrove estuarine ecosystems (Espírito Santo Brazil) by evaluating abiotic and biotic matrices across six trophic levels (plankton, oyster, shrimp, mangrove trees, crabs and fish) and hence interrogates the trophic transfer of these elements and their possible input sources. Using the oyster Crassostrea rhizophorae as a biomonitor, ten EMCs (Bi, Ce, La, Nb, Sn, Ta, Ti, W, Y and Zr) were determined. Bi input was from iron export and pelletizing industries; Ce, La and Y inputs were mainly associated with solid waste from steel production, while Zr, Nb and Ti were related to atmospheric particulate matter emissions. EMCs were detected at various trophic levels, showing biomagnification for most of them in the Santa Cruz estuary but biodilution in Vitória Bay. These contrasting results between the estuaries could be attributed to different pollution degrees, needing further research to be fully understood. This is the first report demonstrating EMCs trophic pathways in situ, constituting an essential baseline for future research and safety regulations involving EMCs in the environment.

Targeted metabolomics to assess the authenticity of bakery products containing chia, sesame and flax seeds.

Food fraud is perpetrated with increasing frequency along the food chain, triggering the need for new and modern tools to detect food authenticity. Chia, flax and sesame seeds are well known for the good nutritional characteristics of their oils, but there is a lack of knowledge regarding the authenticity of these seeds and food products containing them as well. In the present work, we propose a method based on targeted metabolomics to identify the polyphenols present in seeds, which can be used as markers of authenticity. We tentatively identified 44 polyphenols in the different seeds by HPLC-DAD-ESI-qTOF (MS/MS). Chemometrics allowed the selection of 12 compounds, which are nominated as novel markers for seed authentication. Some of these compounds were also found in a lab-scale preparation of cookies supplemented with the studied seeds. The proposed chemical markers resisted the baking process, representing good candidates to be used in the authentication of raw material and bakery products containing these seeds.

Proteomic analysis of Saccharomyces cerevisiae to study the effects of red wine polyphenols on oxidative stress.

Understanding the molecular mechanisms underlying the "French paradox" has contributed to a growing interest in the investigation of the biological activity of red wine polyphenols (RWP). The main goal of this research is to provide valuable information on how RWP could exert their biological action at the cellular level. So, we report a proteomic analysis of S. cerevisiae exposed to both pro-oxidant (H2O2) and antioxidant (wine) agents. Cellular proteome analysis shows that RWP modify the level of certain proteins. Under both normal conditions (Wine treatment) and oxidative stress situations (Wine + H2O2 treatment), the proteins involved in the metabolism and biosynthesis of biomolecules were down-regulated, while one ribosomal protein was up-regulated, probably performing its ribosome-independent functions, and so contributing to the stress defense system. Considering this action mechanism, we suggest that RWP may be acting as mild pro-oxidants and, therefore, exerting a hormetic effect that leads to the strengthening of cells' antioxidant capacity.

Assessment of bioactive compounds and their in vitro bioaccessibility in whole-wheat flour pasta.

We studied the polyphenol profile and antioxidant properties of cooked whole-wheat pasta to evaluate its effective antioxidant capacity, including changes produced by its production and in vitro digestion. The polyphenol profile was studied by HPLC-ESI-MS/MS, while the antioxidant capacity was measured by TEAC and FRAP assays. Results show that the polyphenol profile and antioxidant capacity change along the elaboration of cooked pasta, being the cooking step important to increase the release of bound polyphenols, enhancing their antioxidant properties. On the other hand, the study of the bioaccessibility of polyphenols, using an experimental model that simulates human gastrointestinal digestion and subsequent absorption, showed that only a small fraction of the starting polyphenolic compounds, mainly free polyphenols, could be absorbed by the small intestine; thus, reducing their effective antioxidant capacity. To our knowledge, this is the first report showing the bioaccessibility of hydroxybenzoic acid glucoside, hydroxybenzoic acid diglucoside, tryptophan, 6-C-glucosyl-8-C-arabinosyl-apigenin and diferulic acids.

Bioaccessibility of polyphenols and antioxidant properties of the white grape by simulated digestion and Caco-2 cell assays: Comparative study with its winemaking product.

The primary objective of this study was to assess the changes on phenolic composition and AC (antioxidant capacity) of white grape and its winemaking product, during in vitro gastrointestinal (GI) digestion. Phenolic compounds were evaluated by HPLC-MS/MS. The AC was measured by in vitro (FRAP, ABTS and DPPH) and cellular (Caco-2 cells) assays. Digestion had a reducing effect on phenolic content, being only 31% and 67% of native polyphenols from grapes and wines, respectively, potentially bioaccessible. At same polyphenol concentration, cellular AC of nondigested and digested foods was the same, indicating that changes in phenolic profile did not modify the bioactivity. Phenolic acids, in addition to quercetin, were the most resistant polyphenols to digestion, and would be the most relevant to explain the biological activity of digested foods. Results indicate that the changes occurred in the native phenolic profile of foods as a consequence of GI digestion, do not modify the bioactivity of white grapes and wines.

Multielemental + isotopic fingerprint enables linking soil, water, forage and milk composition, assessing the geographical origin of Argentinean milk.

The aim of this work was to verify the usefulness of multielemental and isotopic fingerprint to differentiate the origin of milk samples from different areas, linking milk fingerprint with those corresponding to soil, water, and forage. Samples from four production areas in Argentina were analysed: 26 elements, δ2H, δ13C, δ15N and δ18O. Milk provenance was assessed using 16 variables (Na, Mg, Al, V, Co, Ni, As, Se, Rb, Sr, Mo, Hg, δ2H, δ18O, δ13C and K/Rb). Generalized Procrustes Analysis (GPA) demonstrated the consensus between soil, water, forage and milk, in addition to differences between studied areas. Canonical Correlation Analysis (CCA) demonstrated significant correlations between the milk-drinking water, milk-forage, and milk-soil. So far, we report a feasible method to establish the milk provenance, assessing the follow up from environmental matrixes (soil + water) to dairy products through the food web (forage) by a combined chemical-isotopic fingerprint.

Differential biochemical responses to metal/metalloid accumulation in organs of an edible fish (Centropomus parallelus) from Neotropical estuaries.

Metal/metalloid accumulation in fish organs elicits biochemical responses indicating the overall fish and environmental health status. This study evaluated the bioaccumulation of metals and metalloid in relation to a suite of biochemical biomarkers (superoxide dismutase, catalase, glutathione-S-transferase, Na+/K+-ATPase, H+-ATPase, acetylcholinesterase activities and the levels of glutathione, metallothionein, lipid peroxidation and oxidized protein) in different organs of fish, Centropomus parallelus, in Vitória Bay and Santa Cruz estuaries (State of Espírito Santo, Brazil) with distinct contamination levels. Metal and metalloid concentrations differ in each organ and were significantly higher in winter than in summer. Chemometric evaluation performed between metal/metalloid accumulation and the biomarkers revealed a complex scenario in which the biomarker responses depend on both metal accumulation and organ/tissue sensitivity. The metal levels in gills indicate fish contamination mainly via water and the low sensitivity of this organ to most metals. Biomarker responses suggested that the metal elimination pathway is through the gills and kidney. The hepatopancreas and kidneys were the most important detoxification organs while muscle was the less reactive tissue. In general, the finding suggested that, C. parallelus is partly able to tolerate such metal contamination. However, it is emphasized that the biomarker responses imply an energetic cost and may affect the growth rate and reproduction. Given the ecological and economic importance of C. parallelus, the level of toxic metals/metalloids in juvenile fish is an important early-warning for the maintenance, conservation and commercial use of this species.

Relation between polyphenol profile and antioxidant capacity of different Argentinean wheat varieties. A Boosted Regression Trees study.

We report the polyphenol profile and antioxidant capacity (AC) of 12 Argentinean wheat varieties from different regions. The polyphenol profile was studied by HPLC-MS. The AC was measured by TEAC and FRAP. Twenty-five polyphenols were identified. ACA 315 and KLEIN GUERRERO varieties showed the highest content of polyphenols, whereas BIOINTA 3004, KLEIN CAPRICORNIO and LE 2330 showed the lowest one. ACA 315 presented the highest AC, while BIOINTA 3004 and KLEIN CAPRICORNIO showed the lowest one. Boosted Regression Trees (BRT) analyses helped finding significant correlations between AC and polyphenol profile, being hydroxybenzoic acid diglucoside, tryptophan, chrysoeriol-6,8-di-C-pentoside and isomers 4, 5, 9 and 12 of diferulic acids key compounds to explain the observed AC. To our knowledge, this is the first report on the interaction between the environment and wheat genotypes evaluated by BRT, showing how the whole polyphenol profile can explain the AC in wheat.

From grape to wine: Changes in phenolic composition and its influence on antioxidant activity.

The evolution of phenolic compounds and their relationship with the antioxidant capacity (AC) of samples taken along the winemaking process of three Vitis vinifera L. cv., Syrah, Merlot and Cabernet Sauvignon grown in Argentina were studied. Forty-five compounds were identified by HPLC-PDA-MS/MS, while the AC was determined by FRAP, ABTS and DPPH assays. Results show that phenolic composition and AC vary along the winemaking process and between varieties. Multiple regression analysis showed a high correlation between phenolic composition and AC of samples, being anthocyanins the main family with significant contribution to AC. In addition, quantitative differences in specific phenolic compounds help to explain differences in AC observed between varieties. A high phenolic content and bioactivity still remain in pomaces which support its use as an inexpensive source of antioxidants.

Matching in Vitro Bioaccessibility of Polyphenols and Antioxidant Capacity of Soluble Coffee by Boosted Regression Trees.

The aim of this study was to evaluate changes in polyphenol profile and antioxidant capacity of five soluble coffees throughout a simulated gastro-intestinal digestion, including absorption through a dialysis membrane. Our results demonstrate that both polyphenol content and antioxidant capacity were characteristic for each type of studied coffee, showing a drop after dialysis. Twenty-seven compounds were identified in coffee by HPLC-MS, while only 14 of them were found after dialysis. Green+roasted coffee blend and chicory+coffee blend showed the highest and lowest content of polyphenols and antioxidant capacity before in vitro digestion and after dialysis, respectively. Canonical correlation analysis showed significant correlation between the antioxidant capacity and the polyphenol profile before digestion and after dialysis. Furthermore, boosted regression trees analysis (BRT) showed that only four polyphenol compounds (5-p-coumaroylquinic acid, quinic acid, coumaroyl tryptophan conjugated, and 5-O-caffeoylquinic acid) appear to be the most relevant to explain the antioxidant capacity after dialysis, these compounds being the most bioaccessible after dialysis. To our knowledge, this is the first report matching the antioxidant capacity of foods with the polyphenol profile by BRT, which opens an interesting method of analysis for future reports on the antioxidant capacity of foods.

Linking soil, water, and honey composition to assess the geographical origin of argentinean honey by multielemental and isotopic analyses.

The objective of this research was to investigate the development of a reliable fingerprint from elemental and isotopic signatures of Argentinean honey to assess its geographical provenance. Honey, soil, and water from three regions (Córdoba, Buenos Aires, and Entre Ríos) were collected. The multielemental composition was determined by ICP-MS. δ(13)C was measured by isotopic ratio mass spectrometry, whereas the (87)Sr/(86)Sr ratio was determined using thermal ionization mass spectrometry. The data were analyzed by chemometrics looking for the association between the elements, stable isotopes, and honey samples from the three studied areas. Honey samples were differentiated by classification trees and discriminant analysis using a combination of eight key variables (Rb, K/Rb, B, U, (87)Sr/(86)Sr, Na, La, and Zn) presenting differences among the studied regions. The application of canonical correlation analysis and generalized procrustes analysis showed 91.5% consensus between soil, water, and honey samples, in addition to clear differences between studied areas. To the authors' knowledge, this is the first report demonstrating the correspondence between soil, water, and honey samples using different statistical methods, showing that elemental and isotopic honey compositions are related to soil and water characteristics of the site of origin.

Elemental and isotopic fingerprint of Argentinean wheat. Matching soil, water, and crop composition to differentiate provenance.

The aim of this study was to investigate if elemental and isotopic signatures of Argentinean wheat can be used to develop a reliable fingerprint to assess its geographical provenance. For this pilot study we used wheat cultivated at three different regions (Buenos Aires, Córdoba, and Entre Ríos), together with matching soil and water. Elemental composition was determined by ICP-MS. δ(13)C and δ(15)N were measured by isotopic ratio mass spectrometry, while (87)Sr/(86)Sr ratio was determined using thermal ionization mass spectrometry. Wheat samples from three sampling sites were differentiated by the combination of 11 key variables (K/Rb, Ca/Sr, Ba, (87)Sr/(86)Sr, Co, Mo, Zn, Mn, Eu, δ(13)C, and Na), demonstrating differences among the three studied regions. The application of generalized Procrustes analysis showed 99.2% consensus between cultivation soil, irrigation water, and wheat samples, in addition to clear differences between studied areas. Furthermore, canonical correlation analysis showed significant correlation between the elemental and isotopic profiles of wheat and those corresponding to both soil and water (r(2) = 0.97, p < 0.001 and r(2) = 0.96, p < 0.001, respectively). To our knowledge, this is the first report demonstrating the correspondence between soil, water, and wheat samples using different statistical methods, showing that wheat elemental and isotopic compositions are mainly related to soil and irrigation water characteristics of the site of growth.

How much do soil and water contribute to the composition of meat? A case study: meat from three areas of Argentina.

The main goal of this study was to propose a reliable method to verify the geographical origin of meat, establishing the influence of soil and water on its isotopic and elemental composition. Thus, beef meat, soil, and water samples were collected from three major cattle-producing regions of Argentina (Buenos Aires, Córdoba, and Entre Ríos). Multielemental composition was determined on these three matrices by inductively coupled plasma mass spectrometry (ICP-MS), δ(13)C and δ(15)N by isotope-ratio mass spectrometry (IRMS), and the (87)Sr/(86)Sr ratio by thermal ionization mass spectrometry (TIMS). Soil and drinking water samples could be characterized and clearly differentiated by combining the isotopic ratios and elements, demonstrating differences in geology and climatic conditions of three regions. Similarly, meat originating at each sampling area was characterized and differentiated using only five key variables (Rb, Ca/Sr, δ(13)C, δ(15)N, and (87)Sr/(86)Sr). Generalized procrustes analysis (GPA), using the three studied matrices (soil, water, and meat) shows consensus between them and clear differences between studied areas. Furthermore, canonical correlation analysis (CCA) demonstrates significant correlation between the chemical-isotopic profile of meat with those corresponding to both soil and water (r(2) = 0.93, p < 0.001; and r(2) = 0.83, p < 0.001, respectively). So far, there are clear coincidences between the meat fingerprint and those from soil/water where cattle grew, presenting a good method to establish beef provenance. To the authors' knowledge this is the first report linking the influence of soil and water all together on the composition of beef, presenting the basis for the authentication of Argentinean beef, which could be extended to meat from different provenances.

Fingerprints for main varieties of argentinean wines: terroir differentiation by inorganic, organic, and stable isotopic analyses coupled to chemometrics.

Our main goal was to investigate if robust chemical fingerprints could be developed for three Argentinean red wines based on organic, inorganic, and isotopic patterns, in relation to the regional soil composition. Soils and wines from three regions (Mendoza, San Juan, and Córdoba) and three varieties (Cabernet Sauvignon, Malbec, and Syrah) were collected. The phenolic profile was determined by HPLC-MS/MS and multielemental composition by ICP-MS; (87)Sr/(86)Sr and δ(13)C were determined by TIMS and IRMS, respectively. Chemometrics allowed robust differentiation between regions, wine varieties, and the same variety from different regions. Among phenolic compounds, resveratrol concentration was the most useful marker for wine differentiation, whereas Mg, K/Rb, Ca/Sr, and (87)Sr/(86)Sr were the main inorganic and isotopic parameters selected. Generalized Procrustes analysis (GPA) using two studied matrices (wine and soil) shows consensus between them and clear differences between studied areas. Finally, we applied a canonical correlation analysis, demonstrating significant correlation (r = 0.99; p < 0.001) between soil and wine composition. To our knowledge this is the first report combining independent variables, constructing a fingerprint including elemental composition, isotopic, and polyphenol patterns to differentiate wines, matching part of this fingerprint with the soil provenance.

Relationship between interannual variation of amino acid profile and pollen content in honey from a small Argentinian region.

With the objective of evaluating the utility of the amino acid profile in the characterization of honey samples, 39 honey samples of two different harvests from a particular production zone in Córdoba, Argentina, were analyzed. Multivariate statistical techniques, such as principal component analysis (PCA), cluster analysis (CA), and multiple correspondence analysis (MCA), were applied to verify the correlation among the amino acid profiles, pollen percentages, and different harvests. PCA, CA, and MCA demonstrate the presence of differences of amino acid profiles between samples of the two harvests, such differences being mainly due to differences in pollen availability. Variation of the flora surrounding the apiary due to agricultural practices makes the analysis of amino acid profile typical for those cases with stabilized flora.