Impact of phenylalanine on Hanseniaspora vineae aroma metabolism during wine fermentation.

Hanseniaspora vineae exhibits extraordinary positive oenological characteristics contributing to the aroma and texture of wines, especially by its ability to produce great concentrations of benzenoid and phenylpropanoid compounds compared with conventional Saccharomyces yeasts. Consequently, in practice, sequential inoculation of H. vineae and Saccharomyces cerevisiae allows to improve the aromatic quality of wines. In this work, we evaluated the impact on wine aroma produced by increasing the concentration of phenylalanine, the main amino acid precursor of phenylpropanoids and benzenoids. Fermentations were carried out using a Chardonnay grape juice containing 150 mg N/L yeast assimilable nitrogen. Fermentations were performed adding 60 mg/L of phenylalanine without any supplementary addition to the juice. Musts were inoculated sequentially using three different H. vineae strains isolated from Uruguayan vineyards and, after 96 h, S. cerevisiae was inoculated to complete the process. At the end of the fermentation, wine aromas were analysed by both gas chromatography-mass spectrometry and sensory evaluation through a panel of experts. Aromas derived from aromatic amino acids were differentially produced depending on the treatments. Sensory analysis revealed more floral character and greater aromatic complexity when compared with control fermentations without phenylalanine added. Moreover, fermentations performed in synthetic must with pure H. vineae revealed that even tyrosine can be used in absence of phenylalanine, and phenylalanine is not used by this yeast for the synthesis of tyrosine derivatives.

Tannat grape pomace as an ingredient for potential functional biscuits: bioactive compound identification, in vitro bioactivity, food safety, and sensory evaluation.

Grape pomace, the main by-product of wine process, shows high potential for the development of functional foods, being a natural source of bioactive compounds and dietary fiber. Thus, the present study proposes the development of five potential functional biscuits. The five formulations were achieved by varying the Tannat grape pomace powder (TGP, 10-20% w/w total wet dough) and sweetener sucralose (2-4% w/w total wet dough) content through a factorial design with central points. TGP microbiological and pesticides analysis were performed as a food safety requirement. Identification of bioactive compounds by HPLC-DAD-MS, in vitro bioactivity (total phenol content, antioxidant by ABTS and ORAC-FL, antidiabetic and antiobesity by inhibition of α-glucosidase and pancreatic lipase, respectively) and sensory properties of the biscuits were evaluated. TGP microbiological and pesticides showed values within food safety criteria. Sensory profiles of TGP biscuits were obtained, showing biscuits with 20% TGP good sensory quality (7.3, scale 1-9) in a cluster of 37 out of 101 consumers. TGP addition in biscuits had a significant (p < 0.05) effect on total phenolic content (0.893-1.858 mg GAE/g biscuit) and bioactive properties when compared to controls: 11.467-50.491 and 4.342-50.912 µmol TE/g biscuit for ABTS and ORAC-FL, respectively; inhibition of α-glucosidase and pancreatic lipase, IC50 35.572-64.268 and 7.197-47.135 mg/mL, respectively. HPLC-DAD-MS results showed all the identified phenolic compounds in 20/4% biscuit (TGP/sucralose%) were degraded during baking. Malvidin-3-O-(6'-p-coumaroyl) glucoside, (+)-catechin, malvidin-3-O-glucoside, and (-)-epicatechin were the main phenolic compounds (in descendent order of content) found. The bioactive properties could be attributed to the remaining phenolic compounds in the biscuits. In conclusion, TGP biscuits seemed to be a promising functional food with potential for ameliorating oxidative stress, glucose and fatty acids levels with good sensory quality.

Chemical Profiles and Cytotoxic Activities of Essential Oils from Six Species of Baccharis Subgenus Coridifoliae (Asteraceae).

Several Baccharis species are popularly known in traditional medicine as "carquejas", "vassouras", "ervas-santas" and "mio-mios", and are used as anti-inflammatories, digestives, and diuretics. This study aimed to investigate the chemical compositions and cytotoxic activities of essential oils (EOs) of six Baccharis species belonging to subgenus Coridifoliae, namely B. albilanosa, B. coridifolia, B. erigeroides, B. napaea, B. ochracea, and B. pluricapitulata. GC/MS analyses of the EOs showed that the oxygenated sesquiterpenes spathulenol (7.32-38.22 %) and caryophyllene oxide (10.83-16.75 %) were the major components for all the species. The EOs of almost all species were cytotoxic against cancer (BT-549, KB, SK-MEL and SK-OV-3) and normal kidney (VERO and LLC-PK1) cell lines, whereas B. erigeroides EO showed cytotoxicity only against LLC-PK1. This article augments the current knowledge about the chemical-biological properties of Baccharis subgenus Coridifoliae and discusses the therapeutic potentials of these economically unexploited plants.

Commercial craft beers produced in Uruguay: Volatile profile and physicochemical composition.

Even beer being the most consumed alcoholic beverage around the world, there is not enough information generated for craft beers produced in Latin America, for either volatile profiles or physicochemical studies. In this work, the chemical and volatile components of ten commercial Blond Ale and nine Indian Pale Ale (IPA) beers from the Uruguayan market were studied using GC-MS. Principal component analysis applied to the data allowed differentiation among the two groups of samples while the volatile compounds and physicochemical parameters responsible for these differences were identified. The physicochemical properties revealed a great diversity between all beer samples even within the same beer style. The main significant differences were obtained for alcohol, polyphenols, bitterness, colour, and pH. Most Blond Ale beer samples were differentiated from IPA ones by raw fermentation aroma compounds such as 1-pentanol, 1-hexanol, hexanoic and isobutyric acids, 4-vinyl guaiacol, and 5,5-dimethyl-2(5H)-furanone. This is the first work that contributes to the knowledge of Uruguayan craft beers. The study also showed the ability of most of the Uruguayan microbreweries to brew Blond Ale and IPA craft beer styles that meet international standards for physicochemical quality.

Biology and physiology of Hanseniaspora vineae: metabolic diversity and increase flavour complexity for food fermentation.

Apiculate yeasts belonging to the genus Hanseniaspora are predominant on grapes and other fruits. While some species, such as Hanseniaspora uvarum, are well known for their abundant presence in fruits, they are generally characterized by their detrimental effect on fermentation quality because the excessive production of acetic acid. However, the species Hanseniaspora vineae is adapted to fermentation and currently is considered as an enhancer of positive flavour and sensory complexity in foods. Since 2002, we have been isolating strains from this species and conducting winemaking processes with them. In parallel, we also characterized this species from genes to metabolites. In 2013, we sequenced the genomes of two H. vineae strains, being these the first apiculate yeast genomes determined. In the last 10 years, it has become possible to understand its biology, discovering very peculiar features compared to the conventional Saccharomyces yeasts, such as a natural and unique G2 cell cycle arrest or the elucidation of the mandelate pathway for benzenoids synthesis. All these characteristics contribute to phenotypes with proved interest from the biotechnological point of view for winemaking and the production of other foods.

The anti-snake activity of Nectandra angustifolia flavonoids on phospholipase A2: In vitro and in silico evaluation.

ETHNOPHARMACOLOGICAL RELEVANCE: Lauraceae family includes Nectandra angustifolia a species widely used in the folk medicine of South America against various maladies. It is commonly used to treat different types of processes like inflammation, pain, and snakebites. Snakes of the Bothrops genus are responsible for about 97% of the ophidic accidents in northeastern Argentina. AIM OF THE STUDY: To evaluate the anti-snake activity of the phytochemicals present in N. angustifolia extracts, identify the compounds, and evaluate their inhibitory effect on phospholipase A2 (PLA2) with in vitro and in silico assays. METHODS: Seasonal variations in the alexiteric potential of aqueous, ethanolic and hexanic extracts were evaluated by inhibition of coagulant, haemolytic, and cytotoxic effects of B. diporus venom. The chemical identity of an enriched fraction obtained by bio-guided fractioning was established by UPLC-MS/MS analysis. Molecular docking studies were carried out to investigate the binding mechanisms of the identified compounds to PLA2 enzyme from snake venom. RESULTS: All the extracts inhibited venom coagulant activity. However, spring ethanolic extract achieved 100% inhibition of haemolytic activity. Bio-guide fractioning led to an enriched fraction (F4) with the highest haemolytic inhibition. Five flavonoids were identified in this fraction; molecular docking and Molecular Dynamics (MD) simulations indicated the binding mechanisms of the identified compounds. The carbohydrates present in some of the compounds had a critical effect on the interaction with PLA2. CONCLUSION: This study shows, for the first time, which compounds are responsible for the anti-snake activity in Nectandra angustifolia based on in vitro and in silico assays. The results obtained in this work support the traditional use of this species as anti-snake in folk medicine.

Protección del ácido clorogénico frente a lesiones inducidas por venzo(a)pireno en Saccharomyces cerevisiae / Protection of chlorogenic acid against benzo(a)pyrene-induced lesions in Saccharomyces cerevisiae / Proteção do ácido clorogênico contra lesões induzidas por benzo(a)pireno em Saccharomyces cerevisiae

El objetivo del presente estudio fue analizar el efecto del ácido clorogénico, uno de los compuestos polifenólicos con mayor concentración en la infusión de Ilex paraguariensis, sobre el daño celular y molecular inducido por el benzo(a)pireno. La infusión de Ilex paraguariensis ("mate") es bebida por la mayoría de los habitantes de Argentina, Paraguay, sur de Brasil y Uruguay. La levadura Saccharomyces cerevisiae (cepas SC7K lys2-3; SX46A y SX46Arad14() se utilizó como modelo eucariota. Las células en crecimiento exponencial se expusieron a concentraciones crecientes de benzo(a)pireno y a tratamientos combinados con una concentración de 250 ng/mL de benzo(a)pireno y ácido clorogénico a una concentración igual a la encontrada en la infusión de yerba mate. Luego de los tratamientos se determinaron fracciones de sobrevida, frecuencia mutagénica y roturas de doble cadena de ADN así como la modulación en la expresión de la proteína Rad14 a través de un análisis de Western Blot. Se observó un aumento significativo en las fracciones de sobrevida así como una disminución en la frecuencia mutagénica después de la exposición combinada con benzo(a)pireno y ácido clorogénico en comparación con los tratamientos con benzo(a)pireno como único agente. En la cepa mutante deficiente en la proteína Rad14 se observó un aumento significativo en la sensibilidad a benzo(a)pireno en comparación con la cepa SC7K lys2-3. En los tratamientos combinados de benzo(a)pireno y ácido clorogénico se observó una importante disminución de la letalidad. Con respecto a la determinación de roturas de doble cadena de ADN no se observó fraccionamiento cromosómico a la concentración de benzo(a)pireno utilizada en los experimentos. Los análisis de Western Blot mostraron un aumento en la expresión de la proteína Rad14 en las muestras tratadas con benzo(a)pireno como único agente en comparación con la muestra control. Adicionalmente se observó una disminución en la expresión de la proteína cuando en los tratamientos se utilizaron benzo(a)pireno y ácido clorogénico combinados. Los resultados indican que el ácido clorogénico disminuye significativamente la actividad mutagénica producida por el benzo(a)pireno, la cual no se encuentra relacionada con un incremento en la remoción de las lesiones inducidas por el sistema de reparación por escisión de nucleótidos.

The aim of this study was to analyze the effect of chlorogenic acid, a polyphenolic compound found at high concentrations in Ilex paraguariensis infusions, on cellular and molecular damage induced by benzo(a)pyrene. Ilex paraguariensis infusions ("mate") are consumed by most of the population in Argentina, Paraguay, southern Brazil and Uruguay. Saccharomyces cerevisiae yeast (SC7K lys2-3; SX46A and SX46Arad14( strains) were used as eukaryotic model organisms. Cells in an exponential growth phase were exposed to increasing concentrations of benzo(a)pyrene, as well as combined treatments of benzo(a)pyrene at a concentration of 250 ng/mL and chlorogenic acid at a concentration matching that which is commonly found in mate. Determinations of surviving fraction, mutagenic frequency and double strand DNA breaks induction were performed, along with the assessment of the modulation of the expression of protein Rad14 by Western Blot. A significant increase of surviving fractions and a decrease in mutagenic frequency were observed after exposure to benzo(a)pyrene plus chlorogenic acid, contrary to benzo(a)pyrene alone. A substantial increase in sensitivity to benzo(a)pyrene was observed for the Rad14 protein-deficient mutating strain when compared to the SC7K lys2-3 strain. An important decrease in lethality was observed when combined benzo(a)pyrene and chlorogenic acid treatments were applied. As for the determination of DSBs, no chromosomic fractionation was observed at the benzo(a)pyrene concentration tested in the experiments. Western Blot analysis showed an increase in the expression of protein Rad14 for samples treated with benzo(a)pyrene as a single agent when compared against the control sample. Additionally, the expression of this protein was observed to diminish when combined treatments with benzo(a)pyrene and chlorogenic acid were used. Results obtained indicate that chlorogenic acid significantly decreases the mutagenic activity of benzo(a)pyrene, which is not related to an increase in the removal of lesions induced by nucleotide excision repair system.

O objetivo deste estudo foi analisar o efeito do ácido clorogênico, um dos compostos polifenólicos com maior concentração na infusão de Ilex paraguariensis, sobre o dano celular e molecular induzido pelo benzopireno. A infusão de Ilex paraguariensis ("mate") é consumida pela maioria dos habitantes da Argentina, Paraguai, sul do Brasil e Uruguai. A levedura Saccharomyces cerevisiae (cepas SC7K lys2-3; SX46A e SX46Arad14() foi utilizada como modelo eucariótico. Células em crescimento exponencial foram expostas a concentrações crescentes de benzopireno e tratamentos combinados foram realizados com uma concentração de 250 ng/mL de benzo(a)pireno e ácido clorogênico, igual à encontrada na infusão de erva-mate. Após os tratamentos, foram determinadas as frações de sobrevivência, frequência mutagênica e quebras de fita dupla do DNA, bem como a modulação na expressão da proteína Rad14 por meio de análise de Western Blot. Um aumento significativo nas frações de sobrevivência, bem como uma diminuição na frequência mutagênica foram observados após a exposição combinada de benzo(a)pireno e ácido clorogênico em comparação com tratamentos de agente único de benzo(a)pireno. Um aumento significativo na sensibilidade ao benzo(a)pireno foi observado na cepa mutante deficiente em proteína Rad14 em comparação com a cepa SC7K lys2-3. Nos tratamentos combinados de benzo(a)pireno e ácido clorogênico, observou-se uma diminuição significativa na letalidade. Com relação à determinação das quebras de fita dupla de DNA, não foi observado fracionamento cromossômico na concentração de benzo(a)pireno utilizada nos experimentos. A partir da análise de Western Blot, observou-se um aumento na expressão da proteína Rad14 nas amostras tratadas com benzo(a)pireno como agente único em relação à amostra controle. Além disso, uma diminuição na expressão da proteína foi observada quando combinados de benzo(a)pireno e ácido clorogênico foram usados ​​nos tratamentos. Os resultados obtidos neste trabalho indicam que o ácido clorogênico diminui significativamente a atividade mutagênica produzida pelo benzo(a)pireno, a qual não está relacionada a um aumento na remoção de lesões induzidas pelo sistema de reparo por excisão de nucleotídeos.

Fecal descriptor in honey: indole from a floral source as an explanation.

BACKGROUND: Animal odor, is one of the most common aroma defects described in the honey odor aroma wheel. It comprises two secondary descriptors: 'fecal' and 'cowshed'. However, the compounds responsible for these honey defects have not been fully identified. In this context, the aim of this work was to identify the compounds responsible for the aromatic defect 'fecal' in Uruguayan honeys by means of gas chromatography coupled to olfactometry (GC-O). RESULTS: Samples of honey described by beekeepers as having fecal aroma were analyzed by GC-O and gas chromatography coupled to mass spectrometry (GC-MS). Through GC-O, it was possible to establish the region of the chromatogram corresponding to the fecal descriptor, while the GC-MS analysis allowed to identify indole as the compound responsible for the fecal descriptor. The content of indole in the analyzed samples ranged between 132 and 414 µg kg-1 . The melissopalynological analysis indicated the presence of Scutia buxifolia ('quebracho' or 'coronilla') pollen in all samples studied. The volatile profile of Scutia buxifolia flowers was evaluated during the full day, enabling the identification of indole as one of its components. The detection threshold value for indole in honey was experimentally determined as 64 µg kg-1 of honey, a value lower than the concentration found in the evaluated samples. CONCLUSION: Results from the study allowed the identification of indole as the compound responsible for the 'fecal' aroma defect in Scutia buxifolia honeys. © 2022 Society of Chemical Industry.

Application of near-infrared spectroscopy/artificial neural network to quantify glycosylated norisoprenoids in Tannat grapes.

Grape variety, vinification, and ageing are factors conditioning the aroma of a wine, with volatile secondary metabolites responsible for the so-called grape varietal character. Particularly, grape glycosylated norisoprenoids are mostly responsible for the sensory profile of Tannat wines, making relevant the use of fast instrumental tools to evaluate their concentration, allow classifying grapes and defining the optimum maturity for harvest. NIR spectroscopy is a fast, non-destructive technique, which requires minimal sample preparation. However, its quantitative applications need chemometric models for interpretation. In this work, a NIR-ANN calibration was developed to quantify norisoprenoids in Vitis vinifera cv. Tannat grapes during maturation and harvesting. Glycosidated norisoprenoids were determined by GC-MS. The ANN adjustments showed better performance than linear models such as PLS, while the best calibration was obtained by homogenising grape samples when comparing to grape juice; making possible to fit a model with an error of 146 µg/kg.

Tannat Grape Skin: A Feasible Ingredient for the Formulation of Snacks with Potential for Reducing the Risk of Diabetes.

In the present work the feasibility of Tannat grape skin (TGS) as a functional ingredient in the formulation of two snacks (yogurt and biscuits) was studied. The research provided novel information on the effects of the food matrix and digestion process, under simulated human oral gastrointestinal conditions, in the bioaccessibility of TGS bioactive compounds composing of the snacks with health promoting properties (antioxidant, anti-inflammatory, and antidiabetic). TGS polyphenolic profile was analyzed by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) finding mainly flavonoids, phenolic acids, and anthocyanins, which may exert antioxidant, anti-inflammatory, and carbohydrase inhibition capacities. TGS digest showed antioxidant and antidiabetic potential compared to the undigested sample (p < 0.05). Yogurt and biscuits with TGS were developed with the nutrition claims "no-added sugars" and "source of fiber" and were digested in vitro to evaluate the bioaccessibility of compounds with health promoting properties after food processing and digestion. After in vitro simulation of digestion, bioactive properties were enhanced for control and TGS snacks which may be attributed to the formation/release of compounds with health-promoting properties. Biscuits showed significant increase in ABTS antioxidant capacity and yogurt showed increased α-glucosidase inhibition capacity by the addition of TGS (p < 0.05). Polyphenols from TGS and bioactive peptides from snacks which may be released during digestion might be responsible for the observed bioactivities. Consumer's acceptance of TGS yogurt and biscuits showed scores of 6.3 and 5.1 (scale 1−9), respectively, showing TGS yogurt had higher overall acceptance. Sensory profile assessed by check-all-that-apply + just-about-right (CATA+JAR) showed most of the attributes were evaluated as "just about right", supporting good food quality. The developed yogurt presented adequate shelf-life parameters for 28 days. TGS yogurt with higher acceptability showed reduced ROS formation (p < 0.05) induced by tert-butyl hydroperoxide (1 mM) in CCD-18Co colon cells and RAW264.7 macrophages when pre-treated with concentrations 500−1000 and 100−500 µg/mL of the digests, respectively. Moreover, TGS yogurt digest pre-treatment reduced nitric oxide (NO) production (p < 0.05) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages, showing anti-inflammatory potential. Bioactive peptides generated during lactic fermentation and digestion process may be contributors to intracellular effects. In conclusion, yogurt and biscuits with Tannat grape skin addition were obtained with nutrition claims "no-added sugars" and "source of fiber" with the potential to modulate key biochemical events associated with diabetes pathogenesis.

Comparison of physicochemical properties, amino acids, mineral elements, total phenolic compounds, and antioxidant capacity of Cuban fruit and rice wines.

Physicochemical characterization, amino acids contents, minerals composition, total phenolic compounds, and antioxidant capacity of Cuban wines from different raw materials were studied. The wines studied were grape wines, tropical fruit wines, and rice wines. Twenty-one amino acids were identified and quantified, being Asp and Glu detected in all wines. The highest concentration of total amino acid content was found in wines elaborated from Cimarrona grape subjected to maceration with grape skins, while the raisined mixture grape wine presented the lowest values, probably caused by the amino acid degradation during the dehydration process by sun exposure. Minerals quantified were range amount limits of acceptable according to the OIV recommendation. Total phenolic compounds and antioxidant capacity showed the greatest values in wine from roasting rice. No statistical separation could be clearly observed by multivariate principal component analysis; however, 3 wine groups could be defined taking account the scores on the PC1.

In Vitro Bioaccessibility of Bioactive Compounds from Citrus Pomaces and Orange Pomace Biscuits.

The present investigation aimed to provide novel information on the chemical composition and in vitro bioaccessibility of bioactive compounds from raw citrus pomaces (mandarin varieties Clemenule and Ortanique and orange varieties Navel and Valencia). The effects of the baking process on their bioaccessibility was also assessed. Samples of pomaces and biscuits containing them as an ingredient were digested, mimicking the human enzymatic oral gastrointestinal digestion process, and the composition of the digests were analyzed. UHPLC-MS/MS results of the citrus pomaces flavonoid composition showed nobiletin, hesperidin/neohesperidin, tangeretin, heptamethoxyflavone, tetramethylscutellarein, and naringin/narirutin. The analysis of the digests indicated the bioaccessibility of compounds possessing antioxidant [6.6-11.0 mg GAE/g digest, 65.5-97.1 µmol Trolox Equivalents (TE)/g digest, and 135.5-214.8 µmol TE/g digest for total phenol content (TPC), ABTS, and ORAC-FL methods, respectively; significant reduction (p < 0.05) in Reactive Oxygen Species (ROS) formation under tert-butyl hydroperoxide (1 mM)-induced conditions in IEC-6 and CCD-18Co cells when pre-treated with concentrations 5-25 µg/mL of the digests], anti-inflammatory [significant reduction (p < 0.05) in nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages], and antidiabetic (IC50 3.97-11.42 mg/mL and 58.04-105.68 mg/mL for α-glucosidase and α-amylase inhibition capacities) properties in the citrus pomaces under study. In addition, orange pomace biscuits with the nutrition claims "no-added sugars" and "source of fiber", as well as those with good sensory quality (6.9-6.7, scale 1-9) and potential health promoting properties, were obtained. In conclusion, the results supported the feasibility of citrus pomace as a natural sustainable source of health-promoting compounds such as flavonoids. Unfractionated orange pomace may be employed as a functional food ingredient for reducing the risk of pathophysiological processes linked to oxidative stress, inflammation, and carbohydrate metabolism, such as diabetes, among others.

Relationship between Baccharis dracunculifolia DC. and B. microdonta DC. (Asteraceae) by Their Different Seasonal Volatile Expression.

Baccharis dracunculifolia DC. and Baccharis microdonta DC. (Asteraceae) are woody species morphologically similar growing in Uruguay, where not taxonomists people often confuse them in field conditions. As the essential oil of B. dracunculifolia ('vassoura' oil) is highly prized by the flavor and fragrance industry, the correct differentiation of the two species is a key factor in exploiting them profitably and reasonably. To differentiate both Baccharis species, in this work their volatile expression profiles were studied as an alternative tool to determine authenticity and quality. Volatile organic compounds (VOCs) were monthly extracted during an entire year from aerial parts of wild populations by simultaneous distillation extraction (SDE), and studied by gas chromatography/mass spectrometry (GC/MS; identification) and conventional gas chromatography (GC-FID; component abundances determination). Enantioselective gas chromatography/mass spectrometry (Es-GC/MS) was applied in the search of parameters able to ensure genuineness of each species extract. Qualitative VOCs profiles were found to be similar for both species, being ß-pinene, limonene, spathulenol, caryophyllene oxide, and viridiflorol the main components. However, the abundance of those VOCs were two to ten times higher in B. dracunculifolia than in B. microdonta during the year of study. These Baccharis spp. showed species-specific patterns of VOCs expression according to the seasonality, and interestingly, oxygenated compounds (trans-pinocarveol and myrtenal) increased their abundances at full-flowering stages. The enantiomeric distribution of selected monoterpenes (α- and ß-pinenes, limonene, linalool, terpinen-4-ol, and α-terpineol) presented differential values for both Baccharis spp., meaning that Es-GC might be a useful tool for differentiating chemically both species in Uruguay for genuineness determination purposes.

In Vitro Bioaccessibility of Extractable Compounds from Tannat Grape Skin Possessing Health Promoting Properties with Potential to Reduce the Risk of Diabetes.

Diabetes pathogenesis encompasses oxidative stress, inflammation, insulin malfunctioning and partial or total insulin secretion impairment, which leads to a constant hyperglycemia. Polyphenols are known to possess bioactive properties, being Tannat grape skin a natural and sustainable source of these compounds. The present study aimed to find out the bioaccessibility of health-promoting molecules composing a multifunctional extract from Tannat grape skin obtained under hydro-alcoholic-acid conditions. The identification of phenolic compounds in the samples was performed by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, the samples were in vitro digested mimicking the human oral gastrointestinal conditions and the bioactivity of the digest (antioxidant, anti-inflammatory and modulation of glucose metabolism) was assessed. Effect on glucose metabolism was estimated by measuring carbohydrases activity and the functionality of glucose transporters of small intestine cells in presence and absence of the digested extract. Flavonoids, phenolic acids and phenolic alcohols were the major phenol compounds detected in the extract. The bioaccessible compounds protected the intestinal cells and macrophages against the induced formation of reactive oxygen species (ROS) and nitric oxide (NO). In addition, glucose transporters were inhibited by the digested extract. In conclusion, the bioaccessible compounds of the extract, including phenols, modulated key biochemical events involved in the pathogenesis of diabetes such as oxidative stress, inflammation and glucose absorption. The extract was effective under prevention with co-administration conditions supporting its potential for either reducing the risk or treating this disease.

Genetic and transcriptomic evidences suggest ARO10 genes are involved in benzenoid biosynthesis by yeast.

Benzenoids are compounds associated with floral and fruity flavours in flowers, fruits and leaves and present a role in hormonal signalling in plants. These molecules are produced by the phenyl ammonia lyase pathway. However, some yeasts can also synthesize them from aromatic amino acids using an alternative pathway that remains unknown. Hanseniaspora vineae can produce benzenoids at levels up to two orders of magnitude higher than Saccharomyces species, so it is a model microorganism for studying benzenoid biosynthesis pathways in yeast. According to their genomes, several enzymes have been proposed to be involved in a mandelate pathway similar to that described for some prokaryotic cells. Among them, the ARO10 gene product could present benzoylformate decarboxylase activity. This enzyme catalyses the decarboxylation of benzoylformate into benzaldehyde at the end of the mandelate pathway in benzyl alcohol formation. Two homologous genes of ARO10 were found in the two sequenced H. vineae strains. In this study, nine other H. vineae strains were analysed to detect the presence and per cent homology of ARO10 sequences by PCR using specific primers designed for this species. Also, the copy number of the genes was estimated by quantitative PCR. To verify the relation of ARO10 with the production of benzyl alcohol during fermentation, a deletion mutant in the ARO10 gene of Saccharomyces cerevisiae was used. The two HvARO10 paralogues were analysed and compared with other α-ketoacid decarboxylases at the sequence and structural level.

The Mandelate Pathway, an Alternative to the Phenylalanine Ammonia Lyase Pathway for the Synthesis of Benzenoids in Ascomycete Yeasts.

Benzenoid-derived metabolites act as precursors for a wide variety of products involved in essential metabolic roles in eukaryotic cells. They are synthesized in plants and some fungi through the phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) pathways. Ascomycete yeasts and animals both lack the capacity for PAL/TAL pathways, and metabolic reactions leading to benzenoid synthesis in these organisms have remained incompletely known for decades. Here, we show genomic, transcriptomic, and metabolomic evidence that yeasts use a mandelate pathway to synthesize benzenoids, with some similarities to pathways used by bacteria. We conducted feeding experiments using a synthetic fermentation medium that contained either 13C-phenylalanine or 13C-tyrosine, and, using methylbenzoylphosphonate (MBP) to inhibit benzoylformate decarboxylase, we were able to accumulate intracellular intermediates in the yeast Hanseniaspora vineae To further confirm this pathway, we tested in separate fermentation experiments three mutants with deletions in the key genes putatively proposed to form benzenoids (Saccharomyces cerevisiaearo10Δ, dld1Δ, and dld2Δ strains). Our results elucidate the mechanism of benzenoid synthesis in yeast through phenylpyruvate linked with the mandelate pathway to produce benzyl alcohol and 4-hydroxybenzaldehyde from the aromatic amino acids phenylalanine and tyrosine, as well as sugars. These results provide an explanation for the origin of the benzoquinone ring, 4-hydroxybenzoate, and suggest that Aro10p has benzoylformate and 4-hydroxybenzoylformate decarboxylase functions in yeast.IMPORTANCE We present here evidence of the existence of the mandelate pathway in yeast for the synthesis of benzenoids. The link between phenylpyruvate- and 4-hydroxyphenlypyruvate-derived compounds with the corresponding synthesis of benzaldehydes through benzoylformate decarboxylation is demonstrated. Hanseniaspora vineae was used in these studies because of its capacity to produce benzenoid derivatives at a level 2 orders of magnitude higher than that produced by Saccharomyces Contrary to what was hypothesized, neither ß-oxidation derivatives nor 4-coumaric acid is an intermediate in the synthesis of yeast benzenoids. Our results might offer an answer to the long-standing question of the origin of 4-hydroxybenzoate for the synthesis of Q10 in humans.

Valorisation of Schinus molle fruit as a source of volatile compounds in foods as flavours and fragrances.

Schinus molle L. (Anacardiaceae) is an evergreen tree native to South America and has been introduced into North and South Africa and the Mediterranean region. The mature berries are known as an alternative to pepper by their pungency and collected for essential oil production to substitute black pepper in perfumery. Several investigators have examined the physicochemical properties and chemical composition of the essential oil, but the release of bound volatile compounds in S. molle berries from the corresponding glycosides is presented here for the first time. The carotenoid content of mature berries was also studied over two successive ripening periods. Ten carotenoids were identified by HPLC-MS/MS: lutein, phytoene, ß-cryptoxanthin, phytofluene, ß-carotene, 9-Z-ß-carotene, ß-cryptoxanthin-C12:0, ß-cryptoxanthin-C14:0, ß-cryptoxanthin-C16:0 and lycopene. This research is the first to characterise the carotenoids in molle berries and their degradation products (norisoprenoids) in the "free" and glycosylated volatile fruit fractions. The detection of many of these glycosidically bound volatile compounds in berries should be considered to have a sensory contribution, which might differentiate the volatile profile. In addition, our results could explain, through the flavour complexity found in both the "free" and glycosylated fractions, the reported traditional use of molle berries as a pepper substitute. For comparison purposes, the essential oil from mature berries obtained by hydrodistillation was also studied.

Chemical and sensory features of Torrontés Riojano sparkling wines produced by second fermentation in bottle using different Saccharomyces strains.

Chemical and sensory properties of Torrontés Riojano sparkling wines, prepared using second fermentation with Saccharomyces strains EC1118, bayanus C12 and IFI473I, were explored. All sparkling wines showed high levels of several volatile ethyl esters and terpenes associated to fruity and floral aromas. The sensory profiles showed significant differences for the floral aroma descriptor among EC1118, bayanus C12 and IFI473I and for bubble persistence for strain bayanus C12. Our results suggest that the sensory properties of these sparkling wines could be dependent on the chemical and organoleptic properties of the base wine more than the yeast strain used for second fermentation.

Phytochemical Findings Evidencing Botanical Origin of New Propolis Type from North-West Argentina.

Propolis samples from north-west Argentina (Amaicha del Valle, Tucumán) were evaluated by palynology, FT-IR spectra, and RP-HPTLC. In addition, the volatile fraction was studied by HS-SPME-GC/MS. The botanical species most visited by Apis mellifera L. near the apiaries were collected and their RP-HPTLC extracts profiles were compared with propolis samples. In addition, GC/MS was performed for volatile compounds from Zuccagnia punctata Cav. (Fabaceae). FT-IR spectra and RP-HPTLC fingerprints of propolis samples showed similar profiles. In RP-HPTLC analyses, only Z. punctata presented a similar fingerprint to Amaicha propolis. The major volatile compounds present in both were trans-linalool oxide (furanoid), 6-camphenone, linalool, trans-pinocarveol, p-cymen-8-ol, and 2,3,6-trimethylbenzaldehyde. Potential variations for the Amaicha del Valle propolis volatile fraction as consequence of propolis sample preparation were demonstrated.

Genomic and Transcriptomic Basis of Hanseniaspora vineae's Impact on Flavor Diversity and Wine Quality.

Hanseniaspora is the main genus of the apiculate yeast group that represents approximately 70% of the grape-associated microflora. Hanseniaspora vineae is emerging as a promising species for quality wine production compared to other non-Saccharomyces species. Wines produced by H. vineae with Saccharomyces cerevisiae consistently exhibit more intense fruity flavors and complexity than wines produced by S. cerevisiae alone. In this work, genome sequencing, assembling, and phylogenetic analysis of two strains of H. vineae showed that it is a member of the Saccharomyces complex and it diverged before the whole-genome duplication (WGD) event from this clade. Specific flavor gene duplications and absences were identified in the H. vineae genome compared to 14 fully sequenced industrial S. cerevisiae genomes. The increased formation of 2-phenylethyl acetate and phenylpropanoids such as 2-phenylethyl and benzyl alcohols might be explained by gene duplications of H. vineae aromatic amino acid aminotransferases (ARO8 and ARO9) and phenylpyruvate decarboxylases (ARO10). Transcriptome and aroma profiles under fermentation conditions confirmed these genes were highly expressed at the beginning of stationary phase coupled to the production of their related compounds. The extremely high level of acetate esters produced by H. vineae compared to that by S. cerevisiae is consistent with the identification of six novel proteins with alcohol acetyltransferase (AATase) domains. The absence of the branched-chain amino acid transaminases (BAT2) and acyl coenzyme A (acyl-CoA)/ethanol O-acyltransferases (EEB1) genes correlates with H. vineae's reduced production of branched-chain higher alcohols, fatty acids, and ethyl esters, respectively. Our study provides sustenance for understanding and potentially utilizing genes that determine fermentation aromas.IMPORTANCE The huge diversity of non-Saccharomyces yeasts in grapes is dominated by the apiculate genus Hanseniaspora Two native strains of Hanseniaspora vineae applied to winemaking because of their high oenological potential in aroma and fermentation performance were selected to obtain high-quality genomes. Here, we present a phylogenetic analysis and the complete transcriptome and aroma metabolome of H. vineae during three fermentation steps. This species produced significantly richer flavor compound diversity than Saccharomyces, including benzenoids, phenylpropanoids, and acetate-derived compounds. The identification of six proteins, different from S. cerevisiae ATF, with diverse acetyltransferase domains in H. vineae offers a relevant source of native genetic variants for this enzymatic activity. The discovery of benzenoid synthesis capacity in H. vineae provides a new eukaryotic model to dilucidate an alternative pathway to that catalyzed by plants' phenylalanine lyases.