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The influence of mepanipyrim (Mep) and tetraconazole (Tetra) and their formulations (Mep-Form and Tetra-Form) on the chromatic characteristics of Mencia wines was evaluated. Fungicides were applied at concentrations corresponding to their Maximum Residue Levels (MRL) on grapes and at 2MRL. The decay rate of both fungicides during winemaking process confirmed the high dissipation percentage (>85%). To evaluate possible modifications in phenolic composition and colour, control wines were also analysed. No effects on anthocyanins for Mep, Mep-Form and Tetra (MRL) treatments were observed. Only a decrease of these pigments was registered when Tetra (2MRL: 43%) and Tetra-Form (MRL: 75% and 2MRL: 64%) were applied. Besides, the addition of Mep, Mep-Form and Tetra to the must did not decrease the content of flavonols, flavan-3-ols and non-flavonoids; meanwhile the addition of Tetra-Form reduced these phenolic compounds (around 35%, 52% and 17%, respectively).

‘Brava’ and ‘Mansa de Figueiredo’ extra-virgin olive oils (EVOOs) are two varieties identified from north-western Spain. A systematic phenolic characterization of the studied oils was undertaken by LC-ESI-IT-MS. In addition, the role of dietary polyphenols from these EVOOs has been evaluated against the inhibition of key enzymes (α-glucosidase and α-amylase) in the management of diabetes mellitus (DM). Oleuropein and ligstroside derivatives comprised 83% and 67% of the total phenolic compounds in ‘Brava’ and ‘Mansa de Figueiredo’ EVOOs, respectively. The main secoiridoids from oleuropein were DOA (3,4-DHPEA-EDA, 59 and 22 mg kg−1, respectively) and the main isomer of OlAgl (3,4-DHPEA-EA, 74 and 23 mg kg−1). The main secoiridoids from ligstroside were D-LigAgl (p-HPEA-EDA or oleocanthal, 23 and 167 mg kg−1) and the main isomer of LigAgl (p-HPEA-EA, 214 and 114 mg kg−1). For α-glucosidase, both EVOO extracts displayed stronger inhibitory activity (IC50 values of 60 ± 8 and 118 ± 9 μg mL−1, respectively) than the commercial inhibitor acarbose (IC50 = 356 ± 21 μg mL−1). Nevertheless, for α-amylase, only ‘Brava’ extracts showed anti-α-amylase capacity. A daily VOO intake lower than the requirements of EFSA seem to be enough to reach both 50% for α-glucosidase and 25% for α-amylase inhibition. These findings support the potential health benefits derived from Galician EVOOs that might be probably linked to the outstanding high concentration levels of phenolic acids and flavonoids.

This study gives new insights to understand the type of interactions between Ginkgo biloba L. and Scutellaria baicalensis Georgi, two Chinese medicinal plants with well documented neuroprotective effects, on three targets in Alzheimer's disease (AD): acetylcholinesterase (AChE) and butyrylcholnesterase (BuChE) inhibition and hydrogen peroxide scavenging. Individual samples, binary mixtures with different proportions of both plant species, and also a commercial multicomponent combination containing both plants together with unroasted Coffea arabica L. and quercetin-3-O-rutinoside were used to perform this in vitro evaluation. Sample phenolic profiles were also determined by HPLC-DAD, showing the presence of several flavonoid glycosides, phenolic acids and a methylxanthine. In order to investigate the possible synergism/antagonism interaction, data obtained were analyzed by CompuSyn software. The results showed that G. biloba and S. baicalensis alone display better activities than in mixtures, most of the interactions exhibiting different degrees of antagonism. A slight synergism interaction was only observed for the commercial multicomponent mixture tested against H2O2. Further analysis was carried out to understand which compounds could be responsible for the antagonistic interaction. Seventeen single pure compounds present in all extracts were tested against AChE inhibition, most of them displaying weak or no activity. Only caffeine had a remarkable activity. Five different binary and quaternary mixture compositions were design to deepen the interaction between these compounds, revealing mainly phenolic acid-flavonoid, flavonoid-flavonoid and methylxanthine-flavonoid-phenolic acid antagonistic interactions. These results clearly show that, for the targets evaluated, there is no potentiation of the neuroprotective effect by combining S. baicalensis and G. biloba extracts.

In this work, phenol-rich extracts from ‘Cornicabra’ and ‘Picual’ virgin-olive oils (EVOOs) were examined, for the first time, to establish their capacity to inhibit key enzymes involved in Alzheimer's disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (LOX)), major depressive disorder (MDD) and Parkinson's disease (PD) (monoamine oxidases: hMAO-A and hMAO-B respectively), and diabetes mellitus (DM) (α-glucosidase and α-amylase). ‘Cornicabra’ displayed the best inhibitory activity against all enzymes, when compared to ‘Picual’: BuChE (IC50 = 156 ± 4 and 308 ± 33 mg mL−1), LOX (IC50 = 26 ± 0.5 and 37 ± 3 mg mL−1), hMAO-A (IC50 = 20 ± 2 and 37 ± 0.2 mg mL−1), hMAO-B (IC50 = 131 ± 7 and 215 ± 13 mg mL−1) and α-glucosidase (IC50 = 154 ± 17 and 251 ± 31 mg mL−1), respectively. The behaviour observed can be associated with the higher content of secoiridoids, lignans and phenolic acids in ‘Cornicabra’ EVOO.

This study focused the toxicity against human gastric adenocarcinoma cells (AGS) and the antioxidant activity of hydromethanol (HME), acetone (AcE) and alkaloid (AE) extracts prepared from the leaves of tomato plant cultivars (Caramba, Valentine, Negro, Abuela, and Anairis). AE, HME and AcE extracts of all cultivars reduced cell viability, IC50 values ranging from 9 ± 2 to 55 ± 11, from 103 ± 25 to 171 ± 29 and from 291 ± 26 to 459 ± 14 μg mL −1 , respectively. Moreover, both HME and AcE extracts scavenged • NO (IC 50 values ranged from 0.87 ± 0.12 to 1.54 ± 0.23 and from 0.90 ± 0.01 to 2.23 ± 0.14 mg mL −1 , respectively), but only HMEs was able to scavenge O 2 •- showing IC 50 values from 0.12 ± ≤0.01 to 0.43 ± 0.08 mg mL −1 . Our results demonstrate that tomato leaves, a by-product of tomato processing industry, are a valuable source of bioactive compounds, providing beneficial properties for human health.

The impact of mepanipyrim (Mep) and its corresponding commercial formulation (Mep Form) on Saccharomyces cerevisiae metabolites was assessed, separately, by using laboratory-scale wine fermentation assays on pasteurized red must. The presence of Mep did not alter the fermentation course. With regard to volatiles formed at the intracellular level by fermenting yeast cells, Mep residues affected mainly the acetate and ethyl ester biochemical pathways. In particular, the target acetates showed a notorious increment, >90%, in presence of commercial Mep Form at the higher dose assayed. The addition of Mep and Mep Form, at both tested levels, highly increased ethyl caprylate (between 42 and 63%) and ethyl caprate (between 36 and 60%) contents as the same as their respective fatty acid precursors. No important effects were observed on colour and non-volatile pyranoanthocyanins, probably due to the low anthocyanin content characteristic of pasteurized musts.

Lycopersicon esculentum Mill. is one of the world’s most important crops and its enormous by-products, such as leaves, are an excellent source of bioactive compounds with potential application in several industries. In this work, extracts from tomato plant leaves (cultivars: Caramba, Valentine, Negro, Abuela, Rio Alto, Anairis, Rosa and Yack) were examined, for the first time, to establish their phytochemical fingerprint and capacity to inhibit key enzymes involved in Alzheimeŕs disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (LOX)) and in diabetes mellitus (DM) (α-glucosidase and α-amylase). The hydromethanol extracts were shown to contain high amounts of phenolics (3774–9252 μg g −1 of dry extract), quercetin-3- O -rutinoside, quercetin-3- O -pentosyl-rutinoside, and chlorogenic and neochlorogenic acids being the major ones. The acetone extracts rich in pigments, namely chlorophylls (46.40 ± 3.81–136.4 ± 7.94 mg g −1 of dry extract), as well as alkaloids extracts rich in tomatine (224 ± 4.39–745 ± 4.96 mg g −1 of dry extract), were also analysed. Moreover, hydromethanol extracts exhibited inhibitory activity against AChE (IC 50 = 3806 ± 113–9911 ± 50.5 μg mL −1 ), BuChE (IC 50 = 133.1 ± 2.68–369.1 ± 17.2 μg mL −1 ), LOX (IC 25 = 35.2 ± 0.49–533 ± 8.9 μg mL −1 ), α-glucosidase (IC 50 = 1.14 ± 0.04–6.48 ± 0.13 mg mL −1 ) and α-amylase (IC 50 = 1.11 ± 0.02–1.78 ± 0.03 mg mL −1 ). On the contrary, the alkaloid extracts were only effective against BuChE (IC 50 = 82.4 ± 1.34–172 ± 10.2 μg mL −1 ). Chemical fingerprint and biological activities varied according to the analysed cultivar. Overall, our results suggest that L. esculentum leaves are promising by-products and valuable sources of bioactive compounds for AD and DM management.

The diet management is imperative to anticipate risk factors that favour the development of diseases; indeed, the intake of virgin olive oil could be an alternative natural source of α-glucosidase enzyme inhibitors, which delay the digestion rate of carbohydrates. Consequently, the impact of diabetes mellitus (DM) could be diminished. Extra Virgin Olive Oils (EVOO) were elaborated from Galician autochthonous variety ‘Brava Gallega’ with olives selected at three different degree of ripeness (ripening index, RI: 1.4, 3.0, 5.5) in order to assess the effect of maturation on overall chemical composition, sensory quality, and enzyme inhibition. The phenolic profile of the EVOOs determined by LC-ESI-IT-MS exhibited quantitative differences as ripening advanced; for example oleocanthal, tyrosol, luteolin and apigenin concentrations were higher in the overripe olive oil (RI 5.5). Anyway, the phenolic extracts (from every tested RI) were more active than acarbose. In particular, those obtained from the most mature olives displayed the most powerful inhibitory activity (IC50 value of 143 µg of dry extract/mL). In addition, the significant effect of these compounds (i.e. luteolin, apigenin, tyrosol and oleocanthal) on the inhibitory activity of the olive oil extracts was demonstrated. Our results suggest that, regardless of RI, the inhibitory activity of ‘Brava Gallega’ olive oils could represent a valuable strategy for reinforcing the health claim of olive oil for phenolic compounds.

The influence of antifungal tetraconazole residues (either as an active substance or as a commercial formulation product) on the fermentative activity of Saccharomyces cerevisiae yeast was evaluated in pasteurized Garnacha red must by using laboratory-scale fermentation assays. The presence of this fungicide promoted a slight decrease in glucose consumption. Volatile fermentative-derived compounds were evaluated in deep. Statistically significant changes were found in methionol (with a mean decrease of around 24%), fatty acids (with increments ranged from 23% to 66%), and ethyl esters (with increases ranged from 23% to 145%) contents when grape musts were enriched with the commercial formulation at both contamination levels assayed. Based on protein mass fingerprinting analysis, it was possible to relate these variations on volatiles content with changes in the activity of several enzymes (Met3p, Met14p, Adh2p, Hmg1p, Erg5p, Erg6p, Erg11p, and Erg20p) involved in the secondary metabolism of yeasts.

The increasing interest in theMediterranean diet is based on the protective effects against several diseases, including neurodegenerative disorders. Polyphenol-rich functional foods have been proposed to be unique supplementary and nutraceutical treatments for these disorders. Extra-virgin olive oils (EVOOs) obtained from 0Brava0 and 0Mansa0, varieties recently identified from Galicia (northwestern Spain), were selected for in vitro screening to evaluate their capacity to inhibit key enzymes involved in Alzheimer0s disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (5-LOX)), major depressive disorder (MDD) and Parkinson0s disease (PD) (monoamine oxidases: hMAO-A and hMAO-B respectively). 0Brava0 oil exhibited the best inhibitory activity against all enzymes, when they are compared to 0Mansa0 oil: BuChE (IC50 = 245 ± 5 and 591 ± 23 mg.mL-1), 5-LOX (IC50 = 45 ± 7 and 106±14 mg.mL-1), hMAO-A (IC50 = 30 ± 1 and 72 ± 10 mg.mL-1) and hMAO-B (IC50 = 191 ± 8 and 208 ±14 mg.mL-1), respectively. The inhibitory capacity of the phenolic extracts could be associated with the content of secoiridoids, lignans and phenolic acids., This work received financial support from Programa de Cooperación Interreg V-A España—Portugal (POCTEP) 2014–2020 (projects Ref.: 0181_NANOEATERS_01_E and Ref: 0377_IBERPHENOL_6_E).

The impact of fungicides mepanipyrim (Mep) and tetraconazole (Tetra) and their corresponding commercial formulations (Mep-Form and Tetra-Form) on the aroma composition of wines was assessed. Fungicide residues can affect the biotransformation of aroma precursors from grapes and/or the yeast metabolism. The results confirmed that both maximum residue levels (MRL and 2xMRL) of Mep promoted benzyl alcohol and 4-vinylguaiacol contents; while MRL and 2xMRL of Mep-Form promoted benzene derivatives (benzyl alcohol, benzaldehyde, and trans-isoeugenol), 2-phenylethanol and γ-nonalactone. The addition of Tetra (2xMRL) and Tetra-Form (MRL and 2xMRL) release higher contents of cis-3-hexen-1-ol and ethyl vanillate and affected yeast metabolism related to phenylacetaldehyde, 2-phenylethanol, methionol, capric acid, ethyl 2-methylbutyrate, ethyl isovalerate, ethyl monosuccionate, diethyl succinate and γ-butyrolactone production. Fungicide residues did not display higher variations in global odour activity values with respect to control wines, although some variations on the "floral", "fruity", "spicy" and "lactic" nuances could be sensed.

“Pedra hume caa” is the common name of five species of Myrcia genus used as traditional medicine for the treatment of diabetes mellitus. In this study, different extracts from Myrcia salicifolia, Myrcia sphaerocarpa, and Myrcia speciosa were investigated for the first time, to identify their phenolic compounds (being 3-O-rhamnoside derivatives of myricetin and quercetin the major ones) and in vitro inhibitory potential against α-glucosidase and α-amylase. These extracts inhibited 90–500 times more α-glucosidase (IC50 = 0.7 to 4.1 μg ml−1) than acarbose and displayed a mild inhibition against α-amylase (IC50 = 6.1 to 29 μg mL−1).