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1.
Insects ; 15(6)2024 May 22.
Article in English | MEDLINE | ID: mdl-38921094

ABSTRACT

The brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is an invasive polyphagous pest often observed in vineyards. In Europe, a gap needs to be filled in the knowledge on H. halys seasonal dynamics and damage on grapes. With this study, we described the seasonal dynamics of H. halys and its distribution in multi-cultivar vineyards, and we evaluated the damage on grape clusters induced by different pest densities. In vineyards, the seasonal occurrence of H. halys varied across time and grape cultivars, and the pest was more abundant on Cabernet Franc, Merlot and, to a lesser extent, Pinot gris. Moreover, higher densities of H. halys were found on red berry cultivars than on white ones, and on cultivars ripening late in the season. An edge effect was also detected in pest distribution within vineyards, with more stink bugs observed in the borders. In the study on pest infestation density, H. halys caused damage on berries, showing differences in susceptibility among different cultivars and with regard to the time of infestation (i.e., plant phenological stages). Halyomorpha halys infestation induced an increase in Botrytis cinerea and sour rot incidence, which probably represents the main issue related to the impact of brown marmorated stink bug on grapevine.

2.
J Plant Res ; 137(2): 265-277, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38148429

ABSTRACT

Resveratrol and its derivatives are the most important phytoalexins with a crucial role in plant defense mechanisms. These compounds can occur either naturally or in response to abiotic stresses. Among them, salinity is one of the major threats to the sustainability and productivity of agro-economically important species, particularly those involved in the vini-viticulture sector. Understating salinity tolerance mechanisms in plants is required for the development of novel engineering tools. This study aimed to investigate the potential role of resveratrol derivatives in salinity tolerance of wild grapevines. Our data revealed that the tolerant Tunisian wild grapevine genotype "Ouchtata" exhibited an increased accumulation of resveratrol derivatives (glycosylated and non-glycosylated resveratrol and t-ɛ-viniferin and hydroxylated t-piceatannol) in both stems and roots, along with an increased total antioxidant activity (TAA) compared to the sensitive genotype "Djebba" under stress conditions, suggesting an involvement of these stilbenes in redox homeostasis, thereby, protecting cells from salt-induced oxidative damage. Overall, our study revealed, for the first time, an active role for resveratrol derivatives in salt stress tolerance in wild grapevine, highlighting their potential use as metabolic markers in future grapevine breeding programs for a sustainable vini-viticulture in salt-affected regions.


Subject(s)
Vitis , Resveratrol/metabolism , Vitis/genetics , Salinity , Salt Stress , Stress, Physiological
3.
BMC Plant Biol ; 23(1): 161, 2023 Mar 25.
Article in English | MEDLINE | ID: mdl-36964496

ABSTRACT

BACKGROUND: Flavescence dorée (FD) is a grapevine disease caused by phytoplasma and it is one of the most destructive pathologies in Europe. Nowadays, the only strategies used to control the epidemics are insecticides against vector, but more sustainable techniques are required. Completely resistant Vitis vinifera varieties have not been uncovered yet, but differences in susceptibility among cultivars and spontaneous recovery from FD symptoms have been observed. The grapevine cultivar 'Tocai friulano' shows very low susceptibility to FD but its defence strategy to counteract the phytoplasma spread has not been deciphered yet. In this work, the mechanisms occurring within 'Tocai friulano' FD-infected plants were examined in depth to identify the phytoplasma distribution and the defence pathways involved. RESULTS: In 'Tocai friulano' symptoms of FD-infection remained confined near the area where they appeared during all the vegetative season. Analyses of secondary phloem showed a total absence of FD phytoplasma (FDp) in the trunk and its disappearance in 2-year-old arms from July to November, which was different from 'Pinot gris', a highly susceptible variety. Diverse modulations of defence genes and accumulation of metabolites were revealed in 1-year-old canes of 'Tocai friulano' FD-infected plants, depending on the sanitary status. Symptomatic portions showed high activation of both jasmonate- and salicylate-mediated responses, together with a great accumulation of resveratrol. Whereas activation of jasmonate-mediated response and high content of ε-viniferin were identified in asymptomatic 1-year-old cane portions close to the symptomatic ones. CONCLUSION: Successful defence mechanisms activated near the symptomatic areas allowed the compartmentation of FD symptoms and phytoplasmas within the infected 'Tocai friulano' plants. These results could suggest specific agronomical practices to be adopted during FD management of this variety, and drive research of resistance genes against FD.


Subject(s)
Phytoplasma , Vitis , Phytoplasma/genetics , Vitis/genetics , Vitis/metabolism , Cyclopentanes/metabolism , Oxylipins/metabolism , Plant Diseases
4.
Healthcare (Basel) ; 10(6)2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35742152

ABSTRACT

Background: Lateral elbow pain (LEP) represents a musculoskeletal disorder affecting the epicondyloid region of the elbow. The terminological framework of this problem in literature, to date, is confusing. This systematic review (SR) aims to analyse the panorama of the scientific literature concerning the pathogenetic framework, treatment, and clinical diagnosis of LEP. Methods: We conducted an SR according to the guidelines of the PRISMA statement. We performed research using the electronic Medline, Epistemonikos, and Cochrane Library databases. The research started on 12 January 2022 and finished on 30 April 2022. We included all systematic reviews and meta-analyses published, in English, between 1989 and 2022. The articles' selection was based on critical appraisal using Amstar 2. In the selected reviews we obtained the etiopathogenic terminology used to describe the symptoms, treatment, and diagnostic criteria of LEP. Results: Twenty-five SRs met the eligibility criteria and were included in the study. From these SRs, 227 RCT articles were analysed and different treatments proposals were extracted, such as exercise, manipulation corticosteroid injection, and surgery. In the selected articles, 10 different terms emerged to describe LEP and 12 different clinical tests. The most common treatments detected in this SR were a conservative multimodal approach (e.g., eccentric exercises, manual therapy, acupuncture, ultrasound), then surgery or other invasive treatments (e.g., corticosteroid injection, tenotomy). The most common term detected in this SR was "lateral epicondylitis" (n = 95, 51.6%), followed by "tennis elbow" (n = 51, 28.1%) and "lateral epicondylalgia" (n = 18, 9.4%). Among the diagnostic tests were painful palpation (n = 101, 46.8%), the Cozen test (n = 91, 42.1%), the pain-free grip-strength test (n = 41, 19.0%), and the Maudsley test (n = 48, 22.2%). A total of 43.1% of RCTs (n = 96) included subjects with LEP > 3 months, 40.2% (n = 85) included patients with LEP < 3 months, and 16.7% of the items (n = 35) were not specified by the inclusion criteria on the onset of symptoms. Conclusions: In this SR, a considerable terminological heterogeneity emerged in the description of LEP, associated with the lack of clear and recognised diagnostic criteria in evaluating and treating patients with lateral elbow pain.

5.
Food Chem X ; 13: 100232, 2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35498974

ABSTRACT

Oil in Water (3:1) emulsions were prepared using potato proteins in the presence or absence of 0.2% k-carrageenan at different pH conditions (3.0, 7.0, and 4.8). These emulsions showed different droplet sizes, stability, appearance, and rheological properties. The best emulsion stability was achieved combining potato proteins and k-carrageenan at pH 3.0, where uniform and small oil droplets (30 µm) were observed. The rheological properties of the emulsions were also different. The highest viscosity and G' were shown by the emulsion prepared with the addition of k-carrageenan at pH 3.0, this being attributed to the onset of a gel-like viscoelastic structure in these conditions. SDS-PAGE indicated that the superior properties of the emulsion prepared with k-carrageenan at pH 3.0 can be attributed to an electrostatic interaction between the positively charged potato proteins and the anionic polysaccharide. This interaction allowed the formation of a strong molecular network able to stabilize the system.

6.
Foods ; 12(1)2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36613220

ABSTRACT

Starmerella bacillaris is a non-Saccharomyces yeast proposed for must fermentation together with Saccharomyces cerevisiae because of its high glycerol and moderate volatile acidity production. Furthermore, it was demonstrated that the same S. bacillaris strains that possess interesting technological properties exhibited antifungal activity against Botrytis cinerea, suggesting the release of this yeast in the vineyard. To obtain a positive effect during the following winemaking process, the maintenance of suitable concentrations of S. bacillaris is essential. Therefore, to obtain information on the survival of S. bacillaris, a small-scale field trial was performed. One week before the harvest, two different concentrations of S. bacillaris (106 and 107 cells/mL) were sprayed on Pinot grigio bunches, and the strain concentration was monitored by means of qPCR during the subsequent fermentation process. In addition, the combined effect of different winemaking techniques was evaluated, i.e., the vinification of juice, juice with marc and cryomaceration treatment. Results demonstrated that, under the tested conditions, S. bacillaris released in the vineyard remained viable for one week on grape bunches and increased glycerol content during the subsequent fermentation process. Different vinification protocols influenced cell concentrations. In particular, the cryomaceration treatment, due to the use of low temperature, supported S. bacillaris growth due to its cryotolerant aptitude. The collected data open new perspectives on the control of alcoholic fermentation, involving both vineyard and cellar management.

7.
Molecules ; 26(4)2021 Feb 21.
Article in English | MEDLINE | ID: mdl-33669973

ABSTRACT

Phenolic acids represent about one-third of the dietary phenols and are widespread in vegetable and fruits. Several plants belonging to both vegetables and medical herbs have been studied for their hydroxycinnamic acid content. Among them, Echinacea purpurea is preferentially used for caffeic acid-derivatives extraction. The wine industry is a source of by-products that are rich in phenolic compounds. This work demonstrates that unripe grape juice (verjuice) presents a simple high-pressure liquid chromatography (HPLC) profile for hydroxycinnamic acids (HCAs), with a great separation of the caffeic-derived acids and a low content of other phenolic compounds when compared to E. purpurea and other grape by-products. Here it is shown how this allows the recovery of pure hydroxycinnamic acids by a simple and fast method, fast protein liquid chromatography (FPLC). In addition, verjuice can be easily obtained by pressing grape berries and filtering, thus avoiding any extraction step as required for other vegetable sources. Overall, the proposed protocol could strongly reduce the engagement of solvent in industrial phenolic extraction.


Subject(s)
Coumaric Acids/chemistry , Phenols/isolation & purification , Vitis/chemistry , Chromatography, High Pressure Liquid , Fruit and Vegetable Juices/analysis , Molecular Structure , Phenols/chemistry
8.
J Sci Food Agric ; 100(13): 4978-4986, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32500544

ABSTRACT

BACKGROUND: Since the second half of the 20th century, the cultivation of ancient and local apple cultivars has almost disappeared from orchards in Italy. Some of these ancient apple cultivars often possess high nutraceutical values and display lower allergenicity than the modern ones, supporting the so-called 'green revolution' theory. RESULTS: In this study, the phenolic composition and the antioxidant activity of five ancient apple cultivars ('Belfiore', 'Pomella Genovese', 'Gravenstein', 'Bella del Bosco', and 'Piatlin') were compared with a 'Golden Delicious' commercial cultivar. Additionally, apples were tested for their potential allergenicity by detecting the presence of Mal d 3, a non-specific lipid transfer protein that represents the main apples' allergen. All apples came from northern Italy (Trentino Region) and were organically produced. Results showed that, for all cultivars, the skins contained more polyphenols than the pulps. 'Bella del Bosco' had the highest amount of polyphenols and antioxidant activity, whereas 'Piatlin' had the lowest phenolic content. All ancient cultivars presented a higher amount of pulp phenolic compounds than 'Golden Delicious'. Immunoblotting techniques showed that 'Bella del Bosco' and 'Piatlin' had very low quantities of Mal d 3 allergen; hence, they can be considered hypoallergenic cultivars. CONCLUSIONS: The preservation of ancient apple cultivars would be of great importance, not only to maintain the biodiversity but also for their nutritional properties. The hypoallergenic activity of some of these cultivars could be of interest also for the preparation of different apple-based products. © 2020 Society of Chemical Industry.


Subject(s)
Antigens, Plant/analysis , Malus/immunology , Phenols/chemistry , Antigens, Plant/immunology , Antioxidants/chemistry , Fruit/chemistry , Fruit/classification , Fruit/immunology , Italy , Malus/chemistry , Malus/classification , Nutritive Value
9.
R Soc Open Sci ; 7(4): 192146, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32431890

ABSTRACT

The differences in life-history traits and processes between organisms living in the same or different populations contribute to their ecological and evolutionary dynamics. We developed mixed-effect model formulations of the popular size-at-age von Bertalanffy and Gompertz growth functions to estimate individual and group variation in body growth, using as a model system four freshwater fish populations, where tagged individuals were sampled for more than 10 years. We used the software Template Model Builder to estimate the parameters of the mixed-effect growth models. Tests on data that were not used to estimate model parameters showed good predictions of individual growth trajectories using the mixed-effects models and starting from one single observation of body size early in life; the best models had R 2 > 0.80 over more than 500 predictions. Estimates of asymptotic size from the Gompertz and von Bertalanffy models were not significantly correlated, but their predictions of size-at-age of individuals were strongly correlated (r > 0.99), which suggests that choosing between the best models of the two growth functions would have negligible effects on the predictions of size-at-age of individuals. Model results pointed to size ranks that are largely maintained throughout the lifetime of individuals in all populations.

10.
Molecules ; 25(7)2020 Apr 03.
Article in English | MEDLINE | ID: mdl-32260104

ABSTRACT

Polyphenols are an important constituent of wines and they are largely studied due to their antioxidant properties and for their effects on wine quality and stability, which is also related to their capacity to bind to proteins. The effects of some selected polyphenols, including procyanidins B1 and B2, tannic acid, quercetin, and rutin, as well as those of a total white wine procyanidin extract on the conformational properties of the major wine protein VVTL1 (Vitis vinifera Thaumatin-Like-1) were investigated by Synchrotron Radiation Circular Dichroism (SRCD). Results showed that VVTL1 interacts with polyphenols as demonstrated by the changes in the secondary (far-UV) and tertiary (near-UV) structures, which were differently affected by different polyphenols. Additionally, polyphenols modified the two melting temperatures (TM) that were found for VVTL1 (32.2 °C and 53.9 °C for the protein alone). The circular dichroism (CD) spectra in the near-UV region revealed an involvement of the aromatic side-chains of the protein in the interaction with phenolics. The data demonstrate the existence of an interaction between polyphenols and VVTL1, which results in modification of its thermal and UV denaturation pattern. This information can be useful in understanding the behavior of wine proteins in presence of polyphenols, thus giving new insights on the phenomena that are involved in wine stability.


Subject(s)
Antigens, Plant/chemistry , Polyphenols/chemistry , Vitis/metabolism , Circular Dichroism , Food Quality , Models, Molecular , Protein Binding , Protein Structure, Secondary , Thermodynamics , Transition Temperature , Vitis/chemistry
11.
J Sci Food Agric ; 100(4): 1741-1747, 2020 Mar 15.
Article in English | MEDLINE | ID: mdl-31821558

ABSTRACT

BACKGROUND: Grapevine canes represent a large source of waste derived from grape cultivation. In the present study, the effect of different processes of storage and different pruning times on the stilbene accumulation on Pinot noir canes was analyzed. Whether the alteration of the secondary metabolism accompanying leafroll symptom expressions could affect the stilbenoid accumulation in canes harvested at pruning time was also investigated. RESULTS: The maximum accumulation of trans-resveratrol and trans-piceatannol was obtained in canes harvested in October and dried at 40 °C. Even in grape canes harvested in October, November, and December and stored for different times at room temperature (20 ± 2 °C) a marked increase in trans-resveratrol and trans-piceatannol was evident, which reached a maximum at around 8 weeks of storage. A significant higher accumulation of trans-resveratrol and trans-piceatannol was also found in canes harvested from symptomatic plants compared to those harvested from asymptomatic plants for all the pruning times. CONCLUSION: This study confirms that the biosynthetic enzyme activities and, particularly, those involved in the stilbene pathway, persist during Pinot noir cane storage at different harvest times, with different storage times and conditions, and different sanitary status. © 2019 Society of Chemical Industry.


Subject(s)
Fruit/growth & development , Plant Diseases/virology , Plant Extracts/analysis , Stilbenes/analysis , Vitis/chemistry , Fruit/chemistry , Seasons , Vitis/growth & development , Vitis/virology , Waste Products/analysis
12.
J Anim Ecol ; 89(3): 921-932, 2020 03.
Article in English | MEDLINE | ID: mdl-31758696

ABSTRACT

Intraspecific trait variability (ITV) maintains functional diversity in populations and communities, and plays a crucial role in ecological and evolutionary processes such as trophic cascades or speciation. Furthermore, functional variation within a species and its populations can help buffer against harmful environmental changes. Trait variability within species can be observed from differences among populations, and between- and within individuals. In animals, ITV can be driven by ontogeny, the environment in which populations live and by within-individual specialization or variation unrelated to growth. However, we still know little about the relative strength of these drivers in determining ITV variation in natural populations. Here, we aimed to (a) measure the relative strength of between- and within-individual effects of body size on ITV over time, and (b) disentangle the trophic changes due to ontogeny from other sources of variability, such as the environment experienced by populations and individual preferences at varying temporal and spatial scales. We used as a model system the endangered marble trout Salmo marmoratus, a freshwater fish living in a restricted geographical area (<900 km2 ) that shows marked changes in diet through ontogeny. We investigated two trophic traits, trophic position and resource use, with stable isotopes (δ15 N and δ13 C), and followed over time 238 individually tagged marble trout from six populations to estimate the trophic changes between and within individuals through ontogeny at three different time-scales (short term: 3 months, medium term: 1 year and long term: 2 years). We found that the relative strength of between- and within-individual effects of body size on trophic position and resource use change strongly over time. Both effects played a similar role in ITV over medium- and long-term time-scales, but within-individual effects were significantly driving trophic variability over short-term scales. Apart from ontogenetic shifts, individuals showed variability in trophic traits as big as the variability estimated between populations. Overall, our results show how the relative strengths of ITV drivers change over time. This study evidences the crucial importance of considering effects of time-scales on functional variability at individual, population and species levels.


Subject(s)
Environment , Trout , Animals , Biological Evolution , Phenotype
13.
Food Chem ; 305: 125506, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31606690

ABSTRACT

Grapes are known to contain high quantity of polyphenolic compounds, including caffeic, coumaric and ferulic acids esterified with tartaric acid, to yield caftaric, coutaric and fertaric acids, respectively. These acids are more abundant in unripe grapes, which can be processed into verjuice, a product that shows intrinsic resistance against microbial growth and significant antioxidant activity. In the present work, the isolation of hydroxycinnamoyl tartaric acids from unripe grape juice by chromatographic techniques was described. Moreover, the capability of caftaric acid to inhibit tyrosinase activity was evaluated by spectrophotometric assays. According to the kinetics parameters calculated, caftaric acid was shown to be a competitive inhibitor of tyrosinase, more potent than the related caffeic and chlorogenic acids, suggesting that it can be used in cosmetic and food industries for the development of natural skin whitening formulations and as an agent able to counteract the enzymatic browning of food.


Subject(s)
Fruit and Vegetable Juices/analysis , Monophenol Monooxygenase/antagonists & inhibitors , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Spectrophotometry , Vitis/chemistry , Enzyme Inhibitors/isolation & purification , Enzyme Inhibitors/pharmacology
14.
Food Res Int ; 123: 251-257, 2019 09.
Article in English | MEDLINE | ID: mdl-31284974

ABSTRACT

Stilbenes, including trans-resveratrol and its derivatives, are compounds naturally present in grapes and have gained a growing interest due to reported health-promoting properties. The production of resveratrol-enriched table grapes has promoted recent research on stress-induced synthesis of stilbenes. The oxidizing properties of ozone have been successfully exploited to its use as sanitizing agent and stilbene elicitor during table grapes storage. In winegrapes, this study represents the first research focused on the effect of postharvest ozone treatments on the accumulation of stilbene compounds. The study was carried out on Moscato bianco winegrapes (Vitis vinifera L.) and several gaseous ozone treatments were investigated differing in ozone dose (30 and 60 µL/L), exposure time (24 h, 48 h, and several days until 30% of weight loss), and delay time until processing (just after and several days after treatment). The stilbene production induced by ozone exposure was assessed in fresh and partially dehydrated winegrapes up to 5, 10, 15, 20, and 30% of weight loss aiming to evaluate the single and combined effect of oxidative and osmotic stresses. The results obtained showed that short-term exposure of fresh winegrapes at 60 µL/L of ozone for 48 h was not effective in inducing resveratrol accumulation just after treatment, but it had an elicitor effect on total stilbenes (+36%) in grapes subsequently dehydrated up to 20% of weight loss with a significant overproduction of trans-resveratrol and trans-piaceatannol. In addition, long-term and continuous treatments under ozone-enriched atmosphere can be also used during dehydration to sanitize winegrapes without affecting negatively the concentration of stilbenes. Therefore, the use of gaseous ozone during storage and dehydration could be indicated to reduce the use of sulfur dioxide and, depending on ozone dose and exposure time, the synthesis of stilbene compounds could increase.


Subject(s)
Food Handling , Ozone , Stilbenes/analysis , Vitis/chemistry , Dehydration , Food Analysis , Food Preservation , Food Storage , Fruit/chemistry , Resveratrol/analysis
15.
J Sci Food Agric ; 99(13): 5702-5710, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31149736

ABSTRACT

BACKGROUND: Glycosylated compounds are one of the main fractions of the yeast cell wall. Thanks to their amphiphilic structure, they have been studied as stabilizers in food emulsions over a broad range of pH conditions with encouraging results. Nevertheless, extraction costs still represent an important limit for their application in the food industry. RESULTS: In this research, four extraction methods were applied to yeast cells exploiting both physical (heating and sonication) and enzymatic approaches (use of three industrial enzyme preparations, namely Glucanex®, Sur Lies and Elevage). A fifth method involving a pure ß-glucanase enzyme (Zymolyase) was taken as reference. These extraction methods were applied to the oenological strain Saccharomyces cerevisiae EC1118, and their extraction yields and chemical properties (quantitative and qualitative determination of sugars and proteins) were studied. Emulsifying activities were determined at three different pH values (3, 5 and 7). Extractions with Physical, Glucanex and Sur Lies methods were the most successful approaches to obtain relevant amounts of yeast compounds with good emulsifying activities for 2:1 oil-in-water emulsions at pH 3 and 7 over 48 h. CONCLUSIONS: These results indicate that there is the potential for the extraction approaches here proposed to become viable tools for the recovery of yeast compounds to be used as emulsifiers in foods. This approach can be considered as the starting point to explore the possibility to exploit yeast by-products from the fermentation processes (e.g. fermentation lees from wine and beer making) as valuable compounds for food applications. © 2019 Society of Chemical Industry.


Subject(s)
Emulsions/chemistry , Enzymes/chemistry , Saccharomyces cerevisiae/chemistry , Biocatalysis , Cell Wall/chemistry
16.
Molecules ; 24(11)2019 Jun 11.
Article in English | MEDLINE | ID: mdl-31212597

ABSTRACT

Fining treatments involve the addition of a substance or a mixture to wine, and are generally carried out in order to clarify, stabilize or modify the wine's organoleptic characteristics. Usually these fining agents will bind the target compound(s) to form insoluble aggregates that are subsequently removed from the wine. The main reasons to perform wine fining treatments are to carry out wine clarification, stabilization and to remove phenolic compounds imparting unwanted sensory characteristics on the wine, which is an operation that often relies on the use of animal proteins, such as casein, gelatin, egg and fish proteins. However, due to the allergenic potential of these animal proteins, there is an increasing interest in developing alternative solutions including the use of fining proteins extracted from plants (e.g., proteins from cereals, grape seeds, potatoes, legumes, etc.), and non-proteinaceous plant-based substances (e.g., cell wall polysaccharides and pomace materials). In this article, the state of the art alternative fining agents of plant origins are reviewed for the first time, including considerations of their organoleptic and technological effects on wine, and of the allergenic risks that they can pose for consumers.


Subject(s)
Plant Proteins/analysis , Wine/analysis , Allergens/analysis , Phenols/analysis , Plant Extracts/analysis , Plant Extracts/chemistry , Seeds/chemistry , Vitis/chemistry
17.
J Agric Food Chem ; 67(19): 5512-5520, 2019 May 15.
Article in English | MEDLINE | ID: mdl-31008600

ABSTRACT

Crude extracts of Vitis vinifera canes represent a natural source of stilbene compounds with well characterized antifungals properties. In our trials, exogenous application of a stilbene extract (SE) obtained from grape canes on grapevine leaves reduces the necrotic lesions caused by Botrytis cinerea. The SE showed to possess a direct antifungal activity by inhibiting the mycelium growth. The activation of some grapevine defense mechanism was also investigated. H2O2 production and activation of mitogen-activated protein kinase (MAPK) phosphorylation cascades as well as accumulation of stilbenoid phytoalexins were explored on grapevine cell suspension. Moreover, the transcription of genes encoding for proteins affecting defense responses was analyzed on grapevine plants. The SE induced some grapevine defense mechanisms including MAPK activation, and the expression of pathogenesis-related (PR) genes and of a gene encoding the glutathione-S-transferase 1 ( GST1) . By contrast, treatment of grapevine leaves with SE negatively regulates de novo stilbene production.


Subject(s)
Botrytis/drug effects , Fungicides, Industrial/pharmacology , Plant Diseases/microbiology , Plant Extracts/pharmacology , Plant Stems/chemistry , Vitis/chemistry , Vitis/microbiology , Botrytis/growth & development , Gene Expression Regulation, Plant , Mycelium/drug effects , Mycelium/growth & development , Plant Leaves/microbiology , Plant Proteins/genetics , Plant Proteins/metabolism , Stilbenes/pharmacology
18.
Food Chem ; 286: 78-86, 2019 Jul 15.
Article in English | MEDLINE | ID: mdl-30827669

ABSTRACT

Verjuice is an acidic unfermented unripe grape juice that has recently been proposed as an alternative to vinegar in different food preparations. In this study, pickled cucumber preserves were industrially prepared using two dilutions of verjuice as acidifying agent and compared with the traditional vinegar-pickled samples. Samples were chemically characterized and subjected to sensory analyses using a trained panel and consumers. The different acidifying agents resulted in pickled cucumbers giving different olfactory and gustatory evaluations. No differences in appearance and texture were found. Despite showing chemical and sensory differences, pickles preserved with verjuice and vinegar had similar overall liking scores for visual, olfactory and gustatory aspects. A key feature of pickles prepared with verjuice is their lack of acetic acid potentially conferring them an additional value, suggesting that verjuice represents a viable alternative to vinegar for the production of pickles with distinctive sensorial properties.


Subject(s)
Cucumis sativus , Food Preservation/methods , Fruit and Vegetable Juices , Vitis , Acetic Acid/analysis , Cucumis sativus/chemistry , Female , Humans , Male , Taste
19.
Adv Protein Chem Struct Biol ; 118: 413-436, 2019.
Article in English | MEDLINE | ID: mdl-31928733

ABSTRACT

While proteins are present in wine at low concentration, and are largely associated with undesirable haze formation in white wines, certain types or fractions make direct and indirect contributions to sensory quality and physical stability. The proteins found in wine represent a small subclass of the total pool of grape proteins that remain soluble in the non-physiological conditions of the wine matrix which is characterised by the presence of alcohol, high acidity, and relatively high levels of phenolic compounds. Although initially stable in these conditions, during storage of white and rosé wines proteins undergo changes leading to haze formation which is considered one of the most relevant non-microbiological defects, and which makes the wine commercially unacceptable. This phenomenon involves the two most abundant proteins present in wines: thaumatin-like proteins and chitinases, both belonging to pathogenesis-related proteins of the grape berry. Haze formation is often triggered by thermal fluctuations occurring during storage of white wines, although the presence of other non-protein-related factors seems to be necessary. Here, we review the characteristics of these two protein families and the factors that influence their solubility with a focus on the disulfide bonds reduction as a possible trigger for the onset of their aggregation.


Subject(s)
Plant Proteins/metabolism , Protein Folding , Wine/analysis , Amino Acid Sequence , Plant Proteins/chemistry , Protein Stability , Sequence Homology, Amino Acid
20.
Ecol Evol ; 8(19): 9600-9613, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30386560

ABSTRACT

Harvesting alters demography and life histories of exploited populations, and there is mounting evidence that rapid phenotypic changes at the individual level can occur when harvest is intensive. Therefore, recreational fishing is expected to induce both ecological and rapid evolutionary changes in fish populations and consequently requires rigorous management. However, little is known about the coupled demographic and evolutionary consequences of alternative harvest regulations in managed freshwater fisheries. We used a structurally realistic individual-based model and implemented an eco-genetic approach that accounts for microevolution, phenotypic plasticity, adaptive behavior, density-dependent processes, and cryptic mortality sources (illegal harvest and hooking mortality after catch and release). We explored the consequences of a range of harvest regulations, involving different combinations of exploitation intensity and minimum and maximum-length limits, on the eco-evolutionary trajectories of a freshwater fish stock. Our 100-year simulations of size-selective harvest through recreational fishing produced negative demographic and structural changes in the simulated population, but also plastic and evolutionary responses that compensated for such changes and prevented population collapse even under intense fishing pressure and liberal harvest regulations. Fishing-induced demographic and evolutionary changes were driven by the harvest regime, and the strength of responses increased with increasing exploitation intensity and decreasing restriction in length limits. Cryptic mortality strongly amplified the impacts of harvest and might be exerting a selective pressure that opposes that of size-selective harvest. "Slot" limits on harvestable length had overall positive effects but lower than expected ability to buffer harvest impacts. Harvest regulations strongly shape the eco-evolutionary dynamics of exploited fish stocks and thus should be considered in setting management policies. Our findings suggest that plastic and evolutionary responses buffer the demographic impacts of fishing, but intense fishing pressure and liberal harvest regulations may lead to an unstructured, juvenescent population that would put the sustainability of the stock at risk. Our study also indicates that high rates of cryptic mortality may make harvest regulations based on harvest slot limits ineffective.

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