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Abstract Background Muscadine grape (Vitis rotundifolia) is resistant to many of the pathogens that negatively impact the production of common grape (V. vinifera), including the bacterial pathogen Xylella fastidiosa subsp. fastidiosa (Xfsf), which causes Pierce’s Disease (PD). Previous studies in common grape have indicated Xfsf delays host immune response with a complex O-chain antigen produced by the wzy gene. Muscadine cultivars range from tolerant to completely resistant to Xfsf, but the mechanism is unknown. Results We assembled and annotated a new, long-read genome assembly for ‘Carlos’, a cultivar of muscadine that exhibits tolerance, to build upon the existing genetic resources available for muscadine. We used these resources to construct an initial pan-genome for three cultivars of muscadine and one cultivar of common grape. This pan-genome contains a total of 34,970 synteny-constrained entries containing genes of similar structure. Comparison of resistance gene content between the ‘Carlos’ and common grape genomes indicates an expansion of resistance (R) genes in ‘Carlos.’ We further identified genes involved in Xfsf response by transcriptome sequencing ‘Carlos’ plants inoculated with Xfsf. We observed 234 differentially expressed genes with functions related to lipid catabolism, oxidation-reduction signaling, and abscisic acid (ABA) signaling as well as seven R genes. Leveraging public data from previous experiments of common grape inoculated with Xfsf, we determined that most differentially expressed genes in the muscadine response were not found in common grape, and three of the R genes identified as differentially expressed in muscadine do not have an ortholog in the common grape genome. Conclusions Our results support the utility of a pan-genome approach to identify candidate genes for traits of interest, particularly disease resistance to Xfsf, within and between muscadine and common grape.

Background: Muscadine grape (Vitis rotundifolia) is resistant to many of the pathogens that negatively impact the production of common grape (V. vinifera), including the bacterial pathogen Xylella fastidiosa subsp. fastidiosa (Xfsf), which causes Pierce's Disease (PD). Previous studies in common grape have indicated Xfsf delays host immune response with a complex O-chain antigen produced by the wzy gene. Muscadine cultivars range from tolerant to completely resistant to Xfsf, but the mechanism is unknown. Results: We assembled and annotated a new, long-read genome assembly for 'Carlos', a cultivar of muscadine that exhibits tolerance, to build upon the existing genetic resources available for muscadine. We used these resources to construct an initial pan-genome for three cultivars of muscadine and one cultivar of common grape. This pan-genome contains a total of 34,970 synteny-constrained entries containing genes of similar structure. Comparison of resistance gene content between the 'Carlos' and common grape genomes indicates an expansion of resistance (R) genes in 'Carlos.' We further identified genes involved in Xfsf response by transcriptome sequencing 'Carlos' plants inoculated with Xfsf. We observed 234 differentially expressed genes with functions related to lipid catabolism, oxidation-reduction signaling, and abscisic acid (ABA) signaling as well as seven R genes. Leveraging public data from previous experiments of common grape inoculated with Xfsf, we determined that most differentially expressed genes in the muscadine response were not found in common grape, and three of the R genes identified as differentially expressed in muscadine do not have an ortholog in the common grape genome. Conclusions: Our results support the utility of a pan-genome approach to identify candidate genes for traits of interest, particularly disease resistance to Xfsf, within and between muscadine and common grape. [ABSTRACT FROM AUTHOR]

Wine is a kind of beverage with a variety of compounds beneficial to human health, which makes it popular all over the world and it contributes importantly to economics. The excessive oxidation of wine has always been a major problem in wine production and storage. Unlike traditional wines which are made from Eurasian grapes, wines made from muscadine grapes (Muscadinia rotundifolia Michx.) can maintain their sensory qualities under natural oxidation conditions for relatively long periods of time despite the insight mechanisms still being unclear. In this study, two muscadine wines, Carlos (CAL) and Noble (NOB), and two traditional wines, Chardonnay (CH) and Marselan (MAS), were chosen for comparison of their compositional alteration during oxidation, in order to analyze the principal components contributing to the antioxidant characteristics of muscadine wines. The DPPH, ORAC, color intensity, and total phenolic content changes during the natural oxidation process were analyzed. Six core significantly changed metabolites (SCMs, avicularin, beta-lactose, delphinidin-3-O-glucoside, ellagic acid, myricetin, and 4-methylcatechol [p < 0.05]) related to the oxidation process were determined. In addition, HPLC–MS was also used to identify pyrogallol which is a unique antioxidant compound in muscadine wine. The present work aims to reveal the crucial antioxidant compounds of muscadine wine and provide valuable information and a new platform for future research on wine oxidation. [ABSTRACT FROM AUTHOR]

Muscadine grapes are abundant in dietary polyphenols, but their effect on hypertension-induced cardiac damage is limited. This study assessed whether a muscadine grape skin/seed extract supplement (MGES) prevents hypertension-induced cardiac damage and oxidative stress. Male Sprague Dawley rats were treated for four weeks with drinking water, angiotensin II (Ang II) to induce hypertension, MGES, or both Ang II and MGES. Cardiac function assessed by echocardiography showed that Ang II increased systolic blood pressure while MGES alone or in combination with Ang II had no effect. Ang II increased E/e′, an indicator of left ventricular filling pressure and diastolic dysfunction, by 41% compared to Control and co-treatment with MGES prevented the Ang II-mediated increase, suggesting that the extract attenuated hypertension-induced diastolic function. Ang II infusion increased urinary 8-hydroxy-2′-deoxyguanosine and cardiac 4-hydroxynonenal and malondialdehyde, which were prevented by the extract. The antioxidant enzymes catalase and superoxide dismutase 1 activity and mRNA were increased significantly in animals treated with MGES alone or in combination with Ang II, suggesting that the extract upregulates oxidative stress defense mechanisms in cardiac tissue. Thus, MGES may serve as a medical food to protect the heart from hypertension-induced diastolic dysfunction caused in part by excessive reactive oxygen species production. [ABSTRACT FROM AUTHOR]

Muscadine grapes accumulate higher amounts of bioactive phenolics compared with other grape species. To identify the molecular events associated with polyphenolic accumulation that influence antioxidant capacity, two contrasting muscadine genotypes (C5 and C6) with varied phenolic/flavonoid content and antioxidant activity were investigated via RNA-sequencing during berry development. The results showed that berry development is concomitant with transcriptome profile changes, which was more pronounced at the véraison (V) stage. Despite that the downregulation pattern of gene expression dominated the upregulation through berry development, the C5 genotype maintained higher expression levels. Comparative transcript profiling allowed the identification of 94 differentially expressed genes with potential relevance in regulating fruit secondary metabolism, including 18 transcription factors and 76 structural genes. The genes underlying the critical enzymes in the modification reactions of polyphenolics biosynthetic pathway, including hydroxylation, methylation, and glycosylation were more pronounced during the immature stages of prevéraison (PrV), V, and postvéraison (PoV) in the C5 genotype, resulting in more accumulation of biologically active phenolic/flavonoid derivatives. The results suggested that muscadine grapes, as in bunch grapes (Vitis sp.); possess a similar mechanism that organizes polyphenolics accumulation; however, the set of total flavonoids (TFs) and structural genes coordinating the pathway varies between the two species. [ABSTRACT FROM AUTHOR]

Muscadine grapes accumulate higher amounts of bioactive phenolics compared with other grape species. To identify the molecular events associated with polyphenolic accumulation that influence antioxidant capacity, two contrasting muscadine genotypes (C5 and C6) with varied phenolic/flavonoid content and antioxidant activity were investigated via RNA-sequencing during berry development. The results showed that berry development is concomitant with transcriptome profile changes, which was more pronounced at the véraison (V) stage. Despite that the downregulation pattern of gene expression dominated the upregulation through berry development, the C5 genotype maintained higher expression levels. Comparative transcript profiling allowed the identification of 94 differentially expressed genes with potential relevance in regulating fruit secondary metabolism, including 18 transcription factors and 76 structural genes. The genes underlying the critical enzymes in the modification reactions of polyphenolics biosynthetic pathway, including hydroxylation, methylation, and glycosylation were more pronounced during the immature stages of prevéraison (PrV), V, and postvéraison (PoV) in the C5 genotype, resulting in more accumulation of biologically active phenolic/flavonoid derivatives. The results suggested that muscadine grapes, as in bunch grapes (Vitis sp.); possess a similar mechanism that organizes polyphenolics accumulation; however, the set of total flavonoids (TFs) and structural genes coordinating the pathway varies between the two species.

Wine is a kind of beverage with a variety of compounds beneficial to human health, which makes it popular all over the world and it contributes importantly to economics. The excessive oxidation of wine has always been a major problem in wine production and storage. Unlike traditional wines which are made from Eurasian grapes, wines made from muscadine grapes (Muscadinia rotundifolia Michx.) can maintain their sensory qualities under natural oxidation conditions for relatively long periods of time despite the insight mechanisms still being unclear. In this study, two muscadine wines, Carlos (CAL) and Noble (NOB), and two traditional wines, Chardonnay (CH) and Marselan (MAS), were chosen for comparison of their compositional alteration during oxidation, in order to analyze the principal components contributing to the antioxidant characteristics of muscadine wines. The DPPH, ORAC, color intensity, and total phenolic content changes during the natural oxidation process were analyzed. Six core significantly changed metabolites (SCMs, avicularin, beta-lactose, delphinidin-3-O-glucoside, ellagic acid, myricetin, and 4-methylcatechol [p < 0.05]) related to the oxidation process were determined. In addition, HPLC–MS was also used to identify pyrogallol which is a unique antioxidant compound in muscadine wine. The present work aims to reveal the crucial antioxidant compounds of muscadine wine and provide valuable information and a new platform for future research on wine oxidation.

Muscadine grapes are abundant in dietary polyphenols, but their effect on hypertension-induced cardiac damage is limited. This study assessed whether a muscadine grape skin/seed extract supplement (MGES) prevents hypertension-induced cardiac damage and oxidative stress. Male Sprague Dawley rats were treated for four weeks with drinking water, angiotensin II (Ang II) to induce hypertension, MGES, or both Ang II and MGES. Cardiac function assessed by echocardiography showed that Ang II increased systolic blood pressure while MGES alone or in combination with Ang II had no effect. Ang II increased E/e′, an indicator of left ventricular filling pressure and diastolic dysfunction, by 41% compared to Control and co-treatment with MGES prevented the Ang II-mediated increase, suggesting that the extract attenuated hypertension-induced diastolic function. Ang II infusion increased urinary 8-hydroxy-2′-deoxyguanosine and cardiac 4-hydroxynonenal and malondialdehyde, which were prevented by the extract. The antioxidant enzymes catalase and superoxide dismutase 1 activity and mRNA were increased significantly in animals treated with MGES alone or in combination with Ang II, suggesting that the extract upregulates oxidative stress defense mechanisms in cardiac tissue. Thus, MGES may serve as a medical food to protect the heart from hypertension-induced diastolic dysfunction caused in part by excessive reactive oxygen species production.

Carbonation is a value-added process that can affect the mouthfeel, perception of volatile compounds, perception of sweetness, and ultimately if a consumer likes a wine. While much work has been completed on traditional varieties of sparkling wine, little research has been completed on niche market wines such as muscadine and fruit wines, which make up a large percentage of wines produced in the Southeastern USA. The objective of this research was to create and evaluate force-carbonated sparkling wine at five carbonation levels. Five finished wines from Florida wineries were obtained, then assessed for the sugar and alcohol content. Each wine was carbonated and then presented to consumers for sensory evaluation (n = 68–89 per evaluation). The questionnaire assessed the perceived sweetness, preference, liking, purchase intent, and comments of each sample. The data illustrated participants consistently preferred the carbonated samples over the noncarbonated sample. The data indicates a roughly even distribution of preference between the four carbonation levels. The data also showed statistically significant differences between the original wine and the carbonated varieties with respect to liking, preference, and purchase intent, which was supported by the consumer’s comments for the most preferred and least preferred samples. Overall, this research serves to impact the wine industry by identifying how carbonation levels affect the acceptability of niche wine varieties, and allows winemakers to successfully expand, diversify, and increase the product portfolio for wineries. [ABSTRACT FROM AUTHOR]

Flooding induces low oxygen (hypoxia) stress to plants, and this scenario is mounting due to hurricanes followed by heavy rains, especially in subtropical regions. Hypoxia stress results in the reduction of green pigments, gas exchange (stomatal conductance and internal CO2 concentration), and photosynthetic activity in the plant leaves. In addition, hypoxia stress causes oxidative damage by accelerating lipid peroxidation due to the hyperproduction of reactive oxygen species (ROS) in leaf and root tissues. Furthermore, osmolyte accumulation and antioxidant activity increase, whereas micronutrient uptake decreases under hypoxia stress. Plant physiology and development get severely compromised by hypoxia stress. This investigation was, therefore, aimed at appraising the effects of regular silicon (Si) and Si nanoparticles (SiNPs) to mitigate hypoxia stress in muscadine (Muscadinia rotundifolia Michx.) plants. Our results demonstrated that hypoxia stress reduced muscadine plants’ growth by limiting the production of root and shoot dry biomass, whereas the root zone application of both Si and SiNP effectively mitigated oxidative and osmotic cell damage. Compared to Si, SiNP yielded better efficiency by improving the activity of enzymatic antioxidants [including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)], non-enzymatic antioxidants [ascorbic acid (AsA) and glutathione contents], and accumulation of organic osmolytes [proline and glycinebetaine (GB)]. SiNP also regulated the nutrient profile of the plants by increasing N, P, K, and Zn contents while limiting Mn and Fe concentration to a less toxic level. A negative correlation between antioxidant activities and lipid peroxidation rates was observed in SiNP-treated plants under hypoxia stress. Conclusively, SiNP-treated plants combat hypoxia more efficiently stress than conventional Si by boosting antioxidant activities, osmoprotectant accumulation, and micronutrient regulation.

Flooding induces low oxygen (hypoxia) stress to plants, and this scenario is mounting due to hurricanes followed by heavy rains, especially in subtropical regions. Hypoxia stress results in the reduction of green pigments, gas exchange (stomatal conductance and internal CO2 concentration), and photosynthetic activity in the plant leaves. In addition, hypoxia stress causes oxidative damage by accelerating lipid peroxidation due to the hyperproduction of reactive oxygen species (ROS) in leaf and root tissues. Furthermore, osmolyte accumulation and antioxidant activity increase, whereas micronutrient uptake decreases under hypoxia stress. Plant physiology and development get severely compromised by hypoxia stress. This investigation was, therefore, aimed at appraising the effects of regular silicon (Si) and Si nanoparticles (SiNPs) to mitigate hypoxia stress in muscadine (Muscadinia rotundifolia Michx.) plants. Our results demonstrated that hypoxia stress reduced muscadine plants' growth by limiting the production of root and shoot dry biomass, whereas the root zone application of both Si and SiNP effectively mitigated oxidative and osmotic cell damage. Compared to Si, SiNP yielded better efficiency by improving the activity of enzymatic antioxidants [including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)], non-enzymatic antioxidants [ascorbic acid (AsA) and glutathione contents], and accumulation of organic osmolytes [proline and glycinebetaine (GB)]. SiNP also regulated the nutrient profile of the plants by increasing N, P, K, and Zn contents while limiting Mn and Fe concentration to a less toxic level. A negative correlation between antioxidant activities and lipid peroxidation rates was observed in SiNP-treated plants under hypoxia stress. Conclusively, SiNP-treated plants combat hypoxia more efficiently stress than conventional Si by boosting antioxidant activities, osmoprotectant accumulation, and micronutrient regulation. [ABSTRACT FROM AUTHOR]

We report to use the main protease (Mpro) of SARS-Cov-2 to screen plant flavan-3-ols and proanthocyanidins. Twelve compounds, (–)-afzelechin (AF), (–)-epiafzelechin (EAF), (+)-catechin (CA), (–)-epicatechin (EC), (+)-gallocatechin (GC), (–)-epigallocatechin (EGC), (+)-catechin-3-O-gallate (CAG), (–)-epicatechin-3-O-gallate (ECG), (–)-gallocatechin-3-O-gallate (GCG), (–)-epigallocatechin-3-O-gallate (EGCG), procyanidin A2 (PA2), and procyanidin B2 (PB2), were selected for docking simulation. The resulting data predicted that all 12 metabolites could bind to Mpro. The affinity scores of PA2 and PB2 were predicted to be −9.2, followed by ECG, GCG, EGCG, and CAG, −8.3 to −8.7, and then six flavan-3-ol aglycones, −7.0 to −7.7. Docking characterization predicted that these compounds bound to three or four subsites (S1, S1′, S2, and S4) in the binding pocket of Mpro via different spatial ways and various formation of one to four hydrogen bonds. In vitro analysis with 10 available compounds showed that CAG, ECG, GCG, EGCG, and PB2 inhibited the Mpro activity with an IC50 value, 2.98 ± 0.21, 5.21 ± 0.5, 6.38 ± 0.5, 7.51 ± 0.21, and 75.3 ± 1.29 μM, respectively, while CA, EC, EGC, GC, and PA2 did not have inhibitory activities. To further substantiate the inhibitory activities, extracts prepared from green tea (GT), two muscadine grapes (MG), cacao, and dark chocolate (DC), which are rich in CAG, ECG, GAG, EGCG, or/and PB2, were used for inhibitory assay. The resulting data showed that GT, two MG, cacao, and DC extracts inhibited the Mpro activity with an IC50 value, 2.84 ± 0.25, 29.54 ± 0.41, 29.93 ± 0.83, 153.3 ± 47.3, and 256.39 ± 66.3 μg/ml, respectively. These findings indicate that on the one hand, the structural features of flavan-3-ols are closely associated with the affinity scores; on the other hand, the galloylation and oligomeric types of flavan-3-ols are critical in creating the inhibitory activity against the Mpro activity.

The plum curculio, Conotrachelus nenuphar Herbst (Coleoptera: Curculionidae), is an insect native to the Americas that is a serious pest of stone and pome fruits in the United States and Canada. Failure to effectively manage this insect may result in up to 85% damaged fruit at harvest, as well as early season fruit abortion. Conotrachelus nenuphar is oligophagous, feeding and ovipositing on many Rosaceous plants, including apple, peach, plum, cherry, quince, and pear. Additionally, C. nenuphar in limited geographic ranges utilizes alternate hosts such as highbush blueberry (Ericaceae) and Muscadine grape (Vitaceae). Despite its long history as a pest, integrated pest management (IPM) lags behind similarly damaging native fruit pests. Although significant progress has been made on the identification of attractive lures for monitoring C. nenuphar adults, development of behaviorally based management strategies, and biological control with entomopathogenic nematodes, growers continue to rely heavily on top-down chemical inputs to manage this pest. Most of the research to date comes from studies done in apples where alternative management practices for C. nenuphar have, to some extent, been adopted; however, less IPM-based information is available for other susceptible crops. In this review, we summarize the history, biology, ecology, behavior, and control of C. nenuphar and future directions for IPM research. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that tends to affect young women and has a high propensity to metastasize. No targeted treatments are available for this type of breast cancer due to a lack of estrogen or progesterone receptors or overexpression of human epidermal growth factor receptor type 2 overexpression. Currently, patients have no therapeutic options once standard of care is complete, indicating a need for safe and effective therapies to slow or prevent the progression of TNBC to metastatic disease. Studies showed that isolated polyphenols or polyphenol-rich muscadine grape extracts polyphenols inhibit the proliferation of various cancer cells including breast cancer. A proprietary muscadine grape extract (MGE) was administered to nude mice with human MDA-MB-231 TNBC atumors for 4 weeks to determine the effect of the extract on tumor growth. MGE decreased tumor volume in association with a reduction in the proliferative markers Ki67 and cyclin D1. To determine the molecular mechanisms for the MGE-induced reduction in tumor growth, mouse 4T1, MDA-MB-231, or human BT-549 TNBC cells were treated with MGE, and various signaling pathways were investigated. MGE reduced c-Met, differentially abrogated ERK/MAPK and AKT signaling, and decreased a downstream targets of ERK/MAPK and AKT pathways, cyclin D1. Cyclin D1 reduction was associated with retinoblastoma activation and cell cycle arrest in MDA-MB-231 TNBC cells. MGE-regulated molecular signaling pathways were functionally associated with a dose-dependent reduction in cell proliferation. The pluripotency of MGE and high index of safety and tolerability suggest that the extract may serve as a therapeutic to reduce TNBC progression to metastatic disease. [ABSTRACT FROM AUTHOR]

In this study, fertility-related traits of 90 muscadine grape genotypes were evaluated. Selected genotypes included 21 standard cultivars, 60 breeding lines, and nine Vitis × Muscadinia hybrids (VM hybrids). The first fruiting bud (FFB), bud fertility (BF), bud fertility coefficient (BFC), number of flowers/flower cluster (N.F/FC), fruit-set efficiency (FSE), number of clusters/vine (N.C/V), and yield/vine (Y/V) traits were evaluated. The FFB trait did not show significant differences among genotypes. The muscadine genotype O28-4-2-2 (1.6 ± 0.2) displayed the FFB closest to the base; however, O17-16-2-1, O18-2-1, and VM A12-10-2 genotypes had the most distant FFB (3.6 ± 0.3). All the other fertility-related traits varied widely among the population. The BF, BFC, N.F/FC, FSE, N.C/V, and Y/V exhibited a range estimated at 35.1%, 81.5%, 259.7, 63.3%, 177 C/V, and 22.3 kg/V, respectively. The muscadine genotypes O42-3-1 (36.7% ± 1.3) and Majesty (34% ± 1.2) exhibited the highest BF; however, the VM A12-10-2 (1.6% ± 0.1) recorded the lowest BF. The VM genotype O15-16-1 (82.8% ± 4.1) displayed the highest BFC; however, the VM A12-10-2 (1.3% ± 0.1) showed the lowest BFC. The muscadine genotypes D7-1-1 (280.3 F/FC ± 21.7) and O17-17-1 (20.7 F/FC ± 5.5) showed the highest and lowest N.F/FC, respectively. The maximum and minimum FSE was observed for the Rosa cultivar (65.7% ± 2.4) and muscadine genotype D7-1-1 (2.4% ± 0.2), respectively. The minimum N.C/V was recorded for VM genotype A12-10-2 (6 C/V ± 0.2) and maximum noted for muscadine genotypes B20-18-2 (183 C/V ± 7.5) and O44-14-1 (176 C/V ± 7.3). Muscadine genotype O23-11-2 (22.6 kg ± 1.1) produced the highest Y/V; however, the lowest yield was recorded for O15-17-1, Fry Seedless, Sugargate, and the VM genotypes and A12-10-2, with an average yield among them estimated at 0.4 kg ± 0.2.

In this study, biometrics assessment of flower structure, cluster-, and berry-related traits were evaluated in a population of 90 muscadine grape genotypes for three consecutive years. This population consisted of 21 standard cultivars, 60 breeding lines, and 9 Vitis x Muscadinia hybrids (VM hybrids). Cluster length (CL) and width (CWI) characteristics exhibited slight differences among the population, with a range estimated at 7.1 and 4.6 cm, respectively. However, cluster weight (CWE), number of berries/cluster (N.B/C), and cluster compactness (CC) traits showed more diversity between individuals with a calculated range of 205.6 g, 32.6 B/C, and 24.1, respectively. Interestingly, all berry-related traits greatly varied between individuals, excluding the number of seeds/berry (N.S/B) character. The N.S/B trait displayed a narrow range of 5.6 seeds within the population. However, characters of berry length (BL), width (BWI), weight (BWE), the weight of seeds/berry (W.S/B), firmness (FF), and dry scar pattern (SP) demonstrated a wide estimated range of 21.2 mm, 21.7 mm, 25.4 g, 0.71 g, 0.21 N, and 82%, respectively. Normal distribution analysis for each trait suggested different distribution patterns extended between unimodal to multimodal behavior. Hierarchical mapping analysis was able to classify the population into several clades based on physical cluster- and berry-related attributes. The PCA suggested that hermaphroditic (perfect) flower structure is associated with compact clusters exhibiting small berries in size and weight (i.e., muscadine genotypes suitable for wine production). However, female flower structure is associated with clusters displaying large berries in size and weight (i.e., muscadine genotypes appropriate for fresh consumption). These patterns occurred independently of cluster size and weight characters. This research is the first study evaluating muscadine biometrics characters at a population level, providing valuable information for market demand and muscadine breeding programs.

Reduced expression of MADS-box gene AGAMOUS-LIKE11 (VviAGL11) is responsible for stenospermocarpic seedlessness in bunch grapes. This study is aimed to characterize the VviAGL11 orthologous gene (VroAGL11) in native muscadine grapes (Vitis rotundifolia) at the molecular level and analyze its divergence from other plants. The VroAGL11 transcripts were found in all muscadine cultivars tested and highly expressed in berries while barely detectable in leaves. RT-PCR and sequencing of predicted ORFs from diverse grape species showed that AGL11 transcripts were conservatively spliced. The encoded VroAGL11 protein contains highly conserved MADS-MEF2-like domain, MADS domain, K box, putative phosphorylation site and two sumoylation motifs. The muscadine VroAGL11 proteins are almost identical (99%) to that of seeded bunch cultivar, Chardonnay, except in one amino acid (A79G), but differs from mutant protein of seedless bunch grape, Sultanina, in two amino acids, R197L and T210A. Phylogenetic analysis showed that AGL11 gene of muscadine and other Vitis species formed a separate clade than that of other eudicots and monocots. Muscadine grape cultivar “Jane Bell” containing the highest percentage of seed content in berry (7.2% of berry weight) had the highest VroAGL11 expression, but almost none to nominal expression in seedless cultivars Fry Seedless (muscadine) and Reliance Seedless (bunch). These findings suggest that VroAGL11 gene controls the seed morphogenesis in muscadine grapes like in bunch grape and can be manipulated to induce stenospermocarpic seedlessness using gene editing technology.

Muscadine wine, fresh muscadine grapes, and other derivatives have enjoyed a heritage niche for decades in the Southeast. Muscadine growers in North Carolina in the United States (US) have asked whether the purchase of muscadine wine is linked to consumption of the fruit itself or even familiarity with other muscadine-based products in terms of spillover effects. The authors explored the interdependency between the market for fresh muscadine grapes and muscadine wine purchase. Consumer panel data were obtained from a State of North Carolina agency with oversight of the grape and wine industry; the agency contracted quota sampling of online consumers from six states in the US South. A total of 543 cases were used in the present study. The Statistical Package for the Social Sciences (SPSS)® was employed in analysis. Results show that prior muscadine wine knowledge and knowledge of other muscadine products, e.g., jams, juices, smoothies, sauces, and health/beauty products were significant factors associated with buying muscadine wine. Beliefs about muscadine grapes as a healthy ingredient showed a slight influence, while direct experience with fresh muscadines and consumer attitudes towards buying local or US products were insignificant. Therefore, marketing efforts should focus on increasing consumer exposure to and knowledge of muscadine wine and other muscadine related products. [ABSTRACT FROM AUTHOR]

Understanding how consumer perception is related to physiochemical attributes assists in the identification of harvest and marketability parameters for muscadine grapes (Vitis rotundifolia Michx.). Three muscadine cultivars (Ison, Nesbitt, and Summit) and three advanced breeding selections (AM-9, AM-74, and AM-83) were harvested from vines at the University of Arkansas System Division of Agriculture Fruit Research Station in Clarksville, AR. The physiochemical (physical and composition) and sensory attributes (descriptive) of the genotypes were evaluated at harvest. Significant differences between genotypes were observed for berry weight (9.25-14.38 g), soluble solids (12.73% to 15.40%), pH (2.88-3.33), titratable acidity (0.54% to 1.01%), soluble solids/titratable acidity ratio (13.12-28.49), skin firmness [0.85-1.48 Newtons/millimeters (N·mm-1)], and flesh firmness (0.89-2.14 N). Total sugars (6.17-9.75 g/100 g) and total organic acid (0.50-0.84 g/100 g) levels were not significantly different for these genotypes. A trained descriptive sensory panel (n = 8) evaluated the fruit attributes for aroma (n = 9), external appearance (n = 7), internal appearance (n = 3), basic tastes (n = 3), aromatics (n = 10), feeling factors (n = 2), and texture (n = 7). The descriptive sensory panel detected differences among genotypes for external appearance, internal appearance, and basic taste attributes, more specifically with desirable attributes rather than unfavorable. However, the panelists found no differences among genotypes for texture attributes. Of the physiochemical attributes, total sugars had the most significant correlations with the descriptive sensory attributes, followed by soluble solids/titratable acidity ratio. Total sugars were correlated to 12 attributes (three aromas, two exterior appearances, two basic tastes, four aromatics, and one feeling factor) and soluble solids/titratable acidity was correlated to five attributes (one aroma, one basic taste, two aromatics, and one feeling factor). A lexicon of terms for descriptive sensory attributes for fresh-market muscadine grapes was established. This lexicon can be used for other research and breeding efforts, as well as establishing the relationship between the physiochemical and descriptive sensory attributes. [ABSTRACT FROM AUTHOR]

ABSTRACT: BACKGROUND: Muscadine grape pomace, a by‐product of juicing and wine‐making, contains significant amounts of anthocyanin 3,5‐diglucosides, known to be beneficial to human health. RESULTS: The objective of this research was to use mathematical modeling to investigate the adsorption/desorption characteristics of these anthocyanins from muscadine grape pomace on Amberlite FPX66 resin in a fixed bed column. Anthocyanins were extracted using hot water and ultrasound, and the extracts were loaded onto a resin column at five bed depths (5, 6, 8, 10 and 12 cm) using three flow rates (4, 6 and 8 mL min−1). It was found that adsorption on the column fitted the bed depth service time (BDST) model and the empty bed residence time (EBRT) model. Desorption was achieved by eluting the column using ethanol at four concentrations (25, 40, 55 and 70% v/v) and could be described with an empirical sigmoid model. The breakthrough curves of anthocyanins fitted the BDST model for all three flow rates with R2 values of 0.983, 0.992 and 0.984 respectively. The EBRT model was successfully employed to find the operating lines, which allow for column scale‐up while still achieving similar results to those found in a laboratory operation. Desorption with 40% (v/v) ethanol achieved the highest recovery rate of anthocyanins at 79.6%. CONCLUSION: The mathematical models established in this study can be used in designing a pilot/industrial‐ scale column for the separation and concentration of anthocyanins from muscadine juice pomace. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Muscadine is a native grape species in the southeastern United States. It has a distinct nutrient composition compared to Vitis vinifera grapes. Most Muscadine grapes are made into wine due to the lack of seedless cultivars, which results in a large amount of Muscadine seeds in the pomace. Muscadine pomace from purple Noble grapes and bronze Carlos grapes are dried and seeds are separated. Seed oils are extracted using a Soxhlet extractor by hexane, mechanical pressing, or enzyme‐assisted aqueous extraction. Oil extraction efficiencies are assessed using yield by dry weight. Oil quality is evaluated by peroxide content, free fatty acid content, fatty acid composition, and tocopherol and tocotrienol content. Extracted seeds oils are refined by degumming, neutralizing, and bleaching. Hexane extraction gives significantly higher yield from both Noble and Carlos seeds followed by mechanical expression and enzyme‐assisted aqueous extraction, respectively. Linoleic acid accounts for 72–79% total fatty acid for all oils. Concentrations of tocopherol and tocotrienol in Noble seed oil ranges from 29.4 to 53.8 mg 100 g−1 and 25.3–44.3 mg 100 g−1, respectively. Concentrations of tocopherol and tocotrienol in Carlos seed oil range from 11.8 to 31.9 mg 100 g−1 and 25.3–33.4 mg 100 g−1, respectively. Refining the oil removes peroxides and free fatty acids without altering fatty acid composition but eliminates 44–100 and 11–95% of tocopherols and tocotrienols, respectively. Practical Applications: Muscadine grape seed oil is high in linoleic acid and antioxidant components, making it an ideal product for culinary, and cosmetic purposes. The unrefined oil is high in tocopherol and tocotrienol, shown to have anti‐adipogenic and anti‐inflammatory capabilities. Grape seed oil is ideal for cooking at high temperatures, with a smoking point of about 190–230 °C being reported before. Grape seed oil is also useful in cosmetics where its hydrophobic nature and antioxidant components could be utilized in skin care products. In this study three different extraction methods are used to obtain oil from muscadine grape seeds of the Noble and Carlos cultivar. In this work, the oil yield efficiencies, peroxide values, free fatty acid content, fatty acid composition, and tocopherol and tocotrienol content are measured in the oil before and after a refining process. In this study, it is found that different extraction methods as well as the refining process, affect the tocopherol and tocotrienol content of the muscadine grape seed oil. [ABSTRACT FROM AUTHOR]

Muscadine grape ( Vitis rotundifolia Michx.) and its wine products are becoming more acceptable due to potential health benefits associated with high concentrations of phenolic compounds. In this research, wines made from eight high-yield muscadine grape varieties grown in Mississippi were compared for their phenolic composition, antioxidant activity, and other quality parameters during different secondary fermentation periods. During the fermentation, the total content of hydroxybenzoic acid derivatives decreased, while that of hydroxycinnamic acid derivatives increased. Changes in total flavonoids varied depending on muscadine cultivar. Total phenolic content (TPC), total benzoic acid (TBA) derivatives and total phenolic acids significantly ( p < 0.05) correlated with DPPH values (r = 0.89, 0.83 and 0.86, respectively), and the r values between TPC and condensed tannin content and the ORAC (oxygen radical absorbance capacity) values were 0.84 and 0.71, respectively. [ABSTRACT FROM AUTHOR]

Fatigue is a prevalent symptom among both cancer survivors and older adults. Negative consequences of fatigue include increased sedentary behavior, decreased physical activity and function, and lower quality of life. Few pharmacologic interventions improve fatigue. Our preclinical and clinical data show promising effects of a muscadine grape extract supplement (MGES) on oxidative stress, mitochondrial bioenergetics, the microbiome, and the symptom of fatigue. This pilot study seeks to translate these observations to cancer survivorship by testing the preliminary effect of MGE supplementation on older adult cancer survivors with self-reported fatigue. We designed a double-blinded placebo-controlled pilot study to evaluate preliminary efficacy of MGE supplementation versus placebo on fatigue among older adult cancer survivors (aged ≥65 years) who report baseline fatigue. Sixty-four participants will be enrolled and randomized 1:1 to twice daily MGES (four tablets twice daily) versus placebo for 12 weeks. The primary outcome is change in Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue score from baseline to 12 weeks. Secondary outcomes are change in self-reported physical function, physical fitness (6-min walk test), self-reported physical activity, global quality of life (QOL), and the Fried frailty index. Correlative biomarker assays will assess changes in 8-hydroxy-2 deoxyguanosine, peripheral blood mitochondrial function, inflammatory markers, and the gut microbiome. This pilot study builds on preclinical and clinical observations to estimate effects of MGE supplementation on fatigue, physical function, QOL, and biologic correlates in older adult cancer survivors. Trial registration #: CT.gov NCT04495751 ; IND 152908. [ABSTRACT FROM AUTHOR]

Stilbenoids such as t-piceid, t-resveratrol, ε-viniferins, and t-pterostilbene can differ significantly among grape cultivars and years due to variation in environmental conditions and subsequent stressors encountered during a year. This study evaluated diverse muscadine grape cultivars for their ability to consistently produce four major stilbenoids such as t-piceid, t-resveratrol, ε-viniferins, and t-pterostilbene irrespective of environmental changes that can impact their production. Berries from forty-two muscadine grape cultivars were collected for three years (2013, 2014, and 2015) to measure stilbenoids. Results showed significant differences in the composition of four stilbenoids among the muscadine cultivars. The highest level of stilbenoids was observed in ‘Fry Seedless’ (270.20 µg/g fresh weight) in each of the three consecutive years tested followed by ‘Pride’ (46.18 µg/g fresh weight) while ‘Doreen’ produced the lowest level of stilbenoids (1.73 µg/g fresh weight). Results demonstrated that certain muscadine grape cultivars consistently produced varied levels of the four major stilbenoids year after year. Based on the total content of stilbenoids, the 42 muscadine cultivars studied were grouped into three categories such as High, Medium and Low stilbenoid-containing cultivars. This information will help establish new vineyards with cultivars that are less prone to variations in environmental conditions and can consistently produce stilbenoid-rich muscadine grape berries with enhanced market value to promote consumer health.

To investigate the values of muscadine grape byproduct, seed oils from 48 muscadine grape cultivars harvested in two seasons were evaluated for their vitamin E isomer content and fatty acid profile. The polyphenol profile and antioxidant properties of the oils were investigated from selected muscadine cultivars. The results showed that muscadine grape seed oils (MGSOs) contained 584.7 mg/kg tocopherols and 517.6 mg/kg tocotrienols, higher than those in other common edible oils. More than 85% of the fatty acids in MGSOs were unsaturated, dominated by linoleic acid. The vitamin E isomer contents were positively correlated with percent linoleic acid in MGSOs which also contained large amounts of phenolic compounds ranging from 124.79 to 358.04 μg/g oil. In addition, MGSOs possessed strong antioxidant activities, which were correlated with the γ-tocopherol and total polyphenol contents in the oils. Collectively, these studies demonstrate that MGSOs are edible oils with great nutritional potential. Practical applications This study presents the identification and characterization of vitamin E isomers and phenolic compounds in seed oils from different muscadine cultivars. The information is highly relevant to the ever-increasing need for natural, renewable sources of nutraceuticals among consumers. The study also shows high contents of tocotrienols and phenolic compounds in the oils, which could lead to a health claim and added value for muscadine processors and growers. [ABSTRACT FROM AUTHOR]

Tons of grape pomace which still contained a rich amount of plant polyphenols, is discarded after winemaking. Plant polyphenols have multi-functional activities for human body. In this study, polyphenols of pomaces from Muscadinia rotundifolia 'Noble' and Vitis vinifera 'Cabernet Sauvignon' were extracted and fractionated, and then they were analyzed with LC-MS and the inhibitory effects on breast cancer cells were compared. The inhibition on MDA-MB-231 cells of fractions from 'Noble' was further evaluated. The results showed that polyphenols from 2 grape pomaces could be separated into 3 fractions, and ellagic acid and/or ellagitannins were only detected in fractions from 'Noble' pomace. All 3 fractions from 'Noble' pomace inhibited MDA-MB-231 better than MCF-7. But fraction 2 from 'Cabernet Sauvignon' inhibited MCF-7 better while fraction 1 and fraction 3 inhibited both 2 cells similarly. Moreover, the fractions from 'Noble' pomace rather than 'Cabernet Sauvignon' can inhibit MDA-MB-231 better. Finally, fractions from 'Noble' pomace can induce S-phase arrest and apoptosis on MDA-MB-231. These findings suggested the extracts from grape pomace especially those from 'Noble,' are potential to be utilized as health beneficial products or even anti-breast cancer agents. [ABSTRACT FROM AUTHOR]

Polyphenol compositions and concentrations in skins and seeds of five muscadine grapes (cv. "Noble", "Alachua", "Carlos", "Fry", and "Granny Val") cultivated in the United States (Tallahassee-Florida, TA-FL) and South China (Nanning-Guangxi, NN-GX and Pu'er-Yunnan, PE-YN) were investigated, using ultra performance liquid chromatography tandem triple quadrupole time-of-flight mass spectrometry (UPLC Triple TOF MS/MS). Fourteen ellagitannins were newly identified in these muscadine grapes. The grapes grown in NN-GX accumulated higher levels of ellagic acid, methyl brevifolin carboxylate, and ellagic acid glucoside in skins, and penta-O-galloyl-glucose in seeds. In PE-YN, more flavonols were detected in skins, and higher contents of flavan-3-ols, ellagic acid, and methyl gallate were identified in seeds. Abundant seed gallic acid and flavonols were found among the grapes grown in TA-FL. Based on principal component analysis (PCA) of 54 evaluation parameters, various cultivars grown in different locations could be grouped together and vice versa for the same cultivar cultivated in different regions. This is the result of the interaction between genotype and environmental conditions, which apparently influences the polyphenol synthesis and accumulation. [ABSTRACT FROM AUTHOR]

Fifty-eight muscadine grape varieties were evaluated for their fruit quality, nutraceutical, and antimicrobial properties during two growing seasons (2012 vs . 2013). Fruit quality was significantly different among muscadine grape varieties, with weight ranged from 2.93 to 22.32 g, pH from 3.01 to 3.84, titratable acidity from 0.27% to 0.83%, and °Brix from 10.92 to 23.91. Total phenols for different muscadine juices varied from 0.26 to 1.28 mg GA/mL, skins from 10.13 to 30.02 mg GA/g DM, and seeds from 22.47 to 72.01 mg GA/g DM. Accordingly, the antioxidant activity of grape juices varied from 0.97 to 6.78 mmol Trolox/mL, skins from 83.59 to 221.20 μmol Trolox/g DM, and seeds from 178.22 to 619.73 μmol Trolox/g DM. Study demonstratedgrape seed polyphenols (MIC 54.8−60.1 μg/ml) showed stronger antimicrobial activity against S. aureus than skin polyphenols (MIC 70.7–80.2 μg/ml). This information could be a valuable asset in the research and extension of muscadine grapes. [ABSTRACT FROM AUTHOR]

C-repeat-binding factor dehydration-responsive element-binding factor 1C ( CBF2/ DREB1C) gene encodes a small family of transcriptional activator that has been described as playing an important role in freezing tolerance and cold acclimation of plants. We here report that CBF2 gene also plays an important role in the early response to the pathogen infection of grapevine downy mildew disease. The expression level of CBF2 increased dramatically and reached a peak at 7 h after infection in immune grapevine Muscadinia rotundifolia 'Noble', which was much faster than moderate resistant Vitis amurensis 'PI1288' and susceptible Vitis vinifera 'Cabernet Sauvignon'. Muscadinia rotundifolia MrCBF2 exhibited amino acid domains characteristic of Vitis CBF2 proteins with unique features including rich serine repeats and slight differences in NLS, DSAWRL, and AP2 domains. The MrCBF2 gene was introduced to Arabidopsis 'COL0' which are susceptible to downy mildew pathogen. The transgenic lines showed an increased resistance to downy mildew disease and more accumulation of SA as well as higher expression of pathogenesis-related ( PR) genes ( AtPR1, AtPR4, and AtPR5) as a consequence of MrCBF2 overexpression. Besides, constitutive expression of MrCBF2 enhanced phytohormone abscisic acid (ABA)-independent drought tolerance of transgenic plants. Freezing tolerance of transgenic lines was also enhanced accompanied with an increase in the expression of the cold-regulated genes AtCOR, AtCOR15A, AtKIN1, AtRD29A, and AtSuSy. In addition, the development of MrCBF2-overexpressing plants was seen to be altered and resulted in growth retardation, dwarfism, late flowering, and prone rosette leaves, which may be because of an increase in the gene expression of partial DELLA proteins and DDF1. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate the acceptability of muscadine grape ( Vitis rotundifolia) genotypes (cultivars and selections) and to correlate overall liking to other quality measurements to determine the main drivers of liking. Twenty-two genotypes grown at the Univ. of Georgia-Tifton Campus were evaluated. Four retail commercial grape genotypes ( Vitis vinifera and 'Concord') were also evaluated for comparison. Panelists familiar with muscadine grapes used the hedonic general labeled magnitude scale (HgLMS, -100 = strongest disliking of any kind ever experienced, +100 = strongest liking of any kind ever experienced) to rate overall liking and the liking of appearance, flavor, pulp texture, and skin texture. Puncture testing was done to assess grape berry texture, and compositional attributes soluble solids and pH were also measured. The sensory results indicated that the grapes were variable with overall liking scores from 12.2 to 39.6. The factors highly correlated with overall liking scores were muscadine flavor, pulp and skin liking, while a significant negative correlation was found between skin liking and skin texture and mechanical texture measures. The muscadine grapes with the highest overall liking scores were Ga. 5-1-34 and Ga. 2-8-21. Principal component analysis confirmed that grapes with a thinner skin and a higher pH tended to group around overall liking and flavor points. These results indicate that even among panelists familiar with muscadine grapes, skin thickness is a negative characteristic. Breeding for thinner skins may be a positive step in muscadines gaining a more widespread appeal in the fresh fruit market. [ABSTRACT FROM AUTHOR]

Muscadine grape skin extract (MSKE) is derived from muscadine grape (Vitis rotundifolia), a common red grape used to produce red wine. Endoplasmic reticulum (ER) stress activates the unfolded protein response (UPR) that serves as a survival mechanism to relieve ER stress and restore ER homeostasis. However, when persistent, ER stress can alter the cytoprotective functions of the UPR to promote autophagy and cell death. Although MSKE has been documented to induce apoptosis, it has not been linked to ER stress/UPR/autophagy. We hypothesized that MSKE may induce a severe ER stress response-mediated autophagy leading to apoptosis. As a model, we treated C4-2 prostate cancer cells with MSKE and performed a quantitative Tandem Mass Tag Isobaric Labeling proteomic analysis. ER stress response, autophagy and apoptosis were analyzed by western blot, acridine orange and TUNEL/Annexin V staining, respectively. Quantitative proteomics analysis indicated that ER stress response proteins, such as GRP78 were greatly elevated following treatment with MSKE. The up-regulation of pro-apoptotic markers PARP, caspase-12, cleaved caspase-3, -7, BAX and down-regulation of anti-apoptotic marker BCL2 was confirmed by Western blot analysis and apoptosis was visualized by increased TUNEL/Annexin V staining upon MSKE treatment. Moreover, increased acridine orange, and LC3B staining was detected in MSKE-treated cells, suggesting an ER stress/autophagy response. Finally, MSKE-mediated autophagy and apoptosis was antagonized by co-treatment with chloroquine, an autophagy inhibitor. Our results indicate that MSKE can elicit an UPR that can eventually lead to apoptosis in prostate cancer cells. [ABSTRACT FROM AUTHOR]

The resistance against phylloxera of the vine is ensured by the morphological and anatomical characteristics of root. The study establish the fact that the first periderm is formed of cells arranged at rizodermoy and that the thickness of the first root periderm in interspecific hybrids of grapes Vitis vinifera L. x Muscadinia rotundifolia Michx., ranges from 80 µm to 124 µm and is formed of 8-12 rows of closely packed cells. The length of these cells varies from 30 µm to 45 µm, and the width varies from 8 µm to 12,5 µm. Fellemy thickness is ranging from 75 µm to 93 µm. The next layer fellemy, if created in the same year, is formed from the deeper layers of the root cortex cells. In the interspecific hybrid DRX-M5-(4-6) a second layer is located beneath the fellemy brown crust with a thickness in the range 93-110 µm. As a result, this area of dead tissue, formed of two layers fellemy, inside and outside, and a layer of crust disposed between two layers fellemy has a thickness in the range 170-180 µm and protects the roots of phylloxera exposure and pathogenic organisms. [ABSTRACT FROM AUTHOR]

A produção homogênea de porta-enxertos resistentes à pérola-da-terra (Eurhizococcus brasiliensis Hempel, Hemiptera: Margarodidae) e adaptados à região vitivinícola do Sul do País, pela técnica de micropropagação, poderá vir a atender à demanda do setor produtivo de uva e evitar as perdas causadas pela praga. O objetivo deste trabalho foi desenvolver um protocolo de micropropagação dos híbridos 1 e 2, que possuem as qualidades genéticas e de vigor desejadas para porta-enxerto, e resistência à pérola-da-terra. A partir de gemas axilares cultivadas em meio Galzy adicionado de 3µM de bezilaminopurina (BAP), foi possível induzir a multibrotação, com um número satisfatório de brotos, passível de ser incrementado por subcultivos sucessivos no mesmo meio de cultura. Os brotos obtidos neste meio e transferidos para o meio de cultura Galzy, adicionado de 8µM.10-3 de ácido naftalenoacético (ANA), enraizaram em 100%, superando a dificuldade de enraizamento que em geral tem sido a maior barreira apresentada pela espécie V. rotundifolia e seus híbridos.The homogeneous production of rootstock resistant to perola-da-terra (Eurhizococcus brasiliensis Hempel, Hemiptera: Margarodidae) and well adapted to the growth conditions of the main grape growing region of Southern Brazil by the use of the micropropagation technique, may come to solve the demand of the grape productive sector and avoid losses caused by this pest. The objective of this work was to develop a protocol of micro propagation for the hybrids 1 and 2, which have the desired genetic qualities and vigor to be used as rootstock resistant to perola-da-terra. From axillaries buds cultivated in Galzy culture medium with 3µM of BAP, it was possible to induce multiple shooting with a reasonable number of shoots, which may be improved by successive subcultures in the same medium. The shoots were transferred to Galzy culture medium with 8µM.10-3 of NAA and all of them rooted, overcoming the rooting step that has been pointed out as the main barrier for micro propagation of the species Viits rotundifolia and its hybrids.

Spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an economically important invasive pest of many soft- and thin-skinned fruits in the United States. This pest has recently threatened blueberry production, a multimillion dollar industry in the southeastern United States. Muscadine grapes are often planted in mixed-crop production systems with blueberries. Although D. suzukii can oviposit in intact soft-skinned grapes, it has yet to be investigated whether muscadine grapes, having thicker-skinned berries, can be a viable host. The goal of this study was to assess the potential of muscadine grapes as a viable host of D. suzukii. Choice and no-choice assays were conducted with two muscadine grape varieties to determine the effect of ripeness and wounding of berries on their susceptibility to D. suzukii infestation. Results from the ripeness assays indicate that D. suzukii was unable to complete development to adulthood in unripe muscadine grapes. D. suzukii was able to complete their development in ripe and overripe grapes, although their success rate was significantly lower than in ripe blueberries. In both choice and no-choice wounding assays, wounded grapes had significantly more oviposition and subsequent development to adulthood than intact grapes. Moreover, wounded muscadines were similar to intact blueberries in D. suzukii oviposition, pupation, and adult eclosion. These data suggest that ripe and overripe muscadine grapes, especially when split and wounded by other pests such as birds, can support D. suzukii development and possibly sustain their populations around berry orchards for a longer period of time after blueberry harvest. [ABSTRACT FROM AUTHOR]

Native muscadines (Vitis rotundifolia Michx.) are dioecious, but muscadine vineyards are usually planted with a mixture of female plants and hermaphroditic pollenizers. Hermaphroditic cultivars are derived from either of two separate sources original hermaphroditic plants, H1 or H2. Nine hermaphroditic and two female cultivars were studied to determine their potential as pollenizers. Inflorescences of each cultivar were collected in the field to evaluate the number of anthers per flower, the number of pollen grains per anther, and pollen viability and germination in the main and secondary flowering periods. The number of flower clusters per shoot ranged from one to four with most producing two or three flower clusters per shoot. The number of anthers per flower varied by cultivar and cluster position, but in general was between six and eight anthers per flower. 'Noble' showed the highest pollen grains production per anther and per flower, reaching 5777 and 39,860, respectively, in the first cluster and 'Carlos' produced the least amount of pollen. All cultivars that had secondary flowering showed lower pollen production per anther and per flower as compared with the main flowering period. Optimal muscadine pollen germination media contained 50 mg·L-1 boric acid, 145 mg·L-1 calcium nitrate, 188 g·L-1 sucrose, 10 g·L-1 agar, and 10 mM 2-(N-morpholino)ethanesulfonic acid (MES) pH 6.0. The pollen grain viability of hermaphroditic and female cultivars was high, but pollen grain germination was low in hermaphroditic cultivars and absent in female cultivars. H1-derived cultivars produced more flower buds per cluster and higher germination rates than H2-derived cultivars, indicating they may be better pollenizers. Chemical names used: 2-(N-morpholino)ethanesulfonic acid (MES). [ABSTRACT FROM AUTHOR]

In the present article are reflected in results of the study about of resveratrol the concentration the juice berries of vine varieties both at the wild and how the culture. As the object of study having served: Muscadinia rotundifolia Michx. and varieties of interspecific hybridization results obtained with Vitis vinifera L. subsp. D.C. sativa, Vitis vinifera L. subsp. sylvestris C.C. Gmel., varieties of vine cultivation. Conducted a comparative analysis about the expressiveness of of resveratrol species of wild the vines and how the expresses the chemical compounds to progeny obtained as a result of hybridization. As a result of the researches it was concluded that the concentration of resveratrol species of wild vine is much larger, nearly double as compared to the descendants of these species and how it are advancing in generations, ie removing us from wild species the concentration of resveratrol decreases in the juice berries of vine. [ABSTRACT FROM AUTHOR]

Acrylamide is a byproduct of the Maillard reaction and is formed in a variety of heat-treated commercial starchy foods. It is known to be toxic and potentially carcinogenic to humans. Muscadine grape polyphenols and standard phenolic compounds were examined on the reduction of acrylamide in an equimolar asparagine/glucose chemical model, a potato chip model, and a simulated physiological system. Polyphenols were found to significantly reduce acrylamide in the chemical model, with reduced rates higher than 90% at 100 μg/ml. In the potato chip model, grape polyphenols reduced the acrylamide level by 60.3% as concentration was increased to 0.1%. However, polyphenols exhibited no acrylamide reduction in the simulated physiological system. Results also indicated no significant correlation between the antioxidant activities of polyphenols and their acrylamide inhibition. This study demonstrated muscadine grape extract can mitigate acrylamide formation in the Maillard reaction, which provides a new value-added application for winery pomace waste. [ABSTRACT FROM AUTHOR]

WRKY transcription factors (TFs) play important roles in many plant processes, including responses to biotic and abiotic stresses. In the present study, Muscadinia rotundifolia MrWRKY30 dramatically accumulated in grapevine leaves in response to inoculation of Plasmopara viticola, a pathogen causing grapevine downy mildew disease. Similar responses were also found on grapevines treated with exogenous SA/JA/ET. Ectopic expression of MrWRKY30 in Arabidopsis thaliana 'COL0' enhanced its resistance to downy mildew pathogen Peronospora parasitica. Pathogenesis-related ( PR) genes, including AtPR1, AtPR4, AtPR5, and AtPDF1.2, were significantly upregulated in transgenic A. thaliana after P. parasitica inoculation. In the mean time, two critical genes in SA and JA signaling pathways, AtEDS5 and AtJAR1, were abundantly expressed as well, indicating that MrWRKY30 may enhance disease resistance of A. thaliana through SA and JA defense system. The transgenic A. thaliana plants also enhanced tolerance to cold stress accompanied with upregulation of AtCBF1, AtCBF3, AtICE1, and AtCOR47. MrWRKY30 might protect A. thaliana from cold damage by activating the AtCBF-mediated signaling pathway to induce the downstream AtCOR47 gene. Interestingly, the transgenic seedlings had a negative effect on salt tolerance. Reverse transcription PCR (RT-PCR) analysis revealed that antioxidant enzyme genes AtAPX (ascorbate peroxidase), AtCAT (catalase), and AtGST (glutathione-S-transferase) were suppressed in transgenic plants, which may lead to reactive oxygen species (ROS)-mediated sensitivity to salt stress. [ABSTRACT FROM AUTHOR]

The Toll/interleukin-1 receptor nucleotide-binding site leucine-rich repeat gene, "resistance to Uncinula necator 1" (RUN1), from Vitis rotundifolia was recently identified and confirmed to confer resistance to the grapevine powdery mildew fungus Erysiphe necator (syn. U. necator) in transgenic V . vinifera cultivars. However, sporulating powdery mildew colonies and cleistothecia of the heterothallic pathogen have been found on introgression lines containing the RUN1 locus growing in New York (NY). Two E. necator isolates collected from RUN1 vines were designated NY1-131 and NY1-137 and were used in this study to inform a strategy for durable RUN1 deployment. In order to achieve this, fitness parameters of NY1-131 and NY1-137 were quantified relative to powdery mildew isolates collected from V. rotundifolia and V . vinifera on vines containing alleles of the powdery mildew resistance genes RUN], RUN2, or REN2. The results clearly demonstrate the race specificity of RUN1, RUN2, and REN2 resistance alleles, all of which exhibit programmed cell death (PCD)-mediated resistance. The NY1 isolates investigated were found to have an intermediate virulence on RUN1 vines, although this may be allele specific, while the Musc4 isolate collected from V . rotundifolia was virulent on all RUN] vines. Another powdery mildew resistance locus, RUN2, was previously mapped in different V. rotundifolia genotypes, and two alleles (RUN2.1 and RUN2.2) were identified. The RUN2.I allele was found to provide PCD-mediated resistance to both an NY1 isolate and Musc4. Importantly, REN2 vines were resistant to the NY1 isolates and RUN1REN2 vines combining both genes displayed additional resistance. Based on these results, RUN!-mediated resistance in grapevine may be enhanced by pyramiding with RUN2.1 or REN2; however, naturally occurring isolates in North America display some virulence on vines with these resistance genes. The characterization of additional resistance sources is needed to identify resistance gene combinations that will further enhance durability. For the resistance gene combinations currently available, we recommend using complementary management strategies, including fungicide application, to reduce populations of virulent isolates. [ABSTRACT FROM AUTHOR]

For the isolation of the genomic deoxyribonucleic acid (DNA) from vine leaves of distant hybrids (Vitis vinifera L. x Muscadinia rotundifolia Michx.), the DNA isolation protocol based on CTAB method was used. The grouping of distant hybrids in the obtained dendrogram shows that at the DNA level there are some differences between them, differences sometimes unnoticeable at the level of ampelographic characterization. As a result, in the characterization of varieties and hybrids of vines, the ampelographic analysis needs to be supplemented by an analysis at the molecular level, based on DNA amplification techniques. As a result of distant hybrids grouping based on the size of alleles, it was found that there are two distinct main groups denoted by A and B, each having secondary branches. The hybrid F4 BC3 DRX-M4-541 1 is closely akin to the variety Chasellas dóre. Also, the two samples of Vitis vylvestris Gmel. have been found to be genetically different, being placed in different subgroups. The hybrid F4 BC3 DRX-M4-536 is genetically close to the male specimen of Vitis sylvestris Gmel. The distant hybrid DRX-M4-660, which proved to have larger differences at the molecular level, isn't grouped in a cluster with any other hybrid. [ABSTRACT FROM AUTHOR]

Muscadine grapes (Vitis rotundifolia Michx.) are native to the southeastern United States and have potential for greater fresh-market sales if postharvest storage can be improved, but limited information is available on postharvest storability. In 2012 and 2013, physiochemical and storability attributes were measured in 17 muscadine genotypes (selections and cultivars) from the muscadine breeding program at the University of Arkansas or commercial cultivars. The postharvest and physiochemical attributes of the muscadines were measured at harvest and during storage for 3 weeks at 2 °C. Nutraceutical compounds were measured initially after harvest. As a result of extreme differences in weather in 2012 and 2013, the data were analyzed by year. Genotypes significantly affected storage attributes [weight loss (%), and unmarketable berries (%)] and physiochemical attributes such as penetration force (force to penetrate berry skin), titratable acidity (TA), pH, soluble solids (%), berry color (L*, chroma, and hue) as well as the nutraceutical compounds. The postharvest attributes of weight loss and unmarketable berries and the physiochemical attribute of penetration force were significantly affected by postharvest storage, but berry composition attributes remained fairly constant during storage. Overall, University of Arkansas selections AM 04, AM 26, AM 28, and the cultivar Southern Jewel had the highest potential for postharvest storage, whereas the genotypes AM 01, AM 15, AM 18, and 'Nesbitt' had the least potential. Genotypes AM 03, AM 04, AM 27, and 'Ison' had the highest nutraceutical contents [total anthocyanins, total phenolics, total flavonols, resveratrol, and oxygen radical absorbance capacity (ORAC)], whereas AM 18, AM 28, 'Supreme', and 'Tara' had the lowest contents. Postharvest storage potential, berry composition, berry color, and nutraceutical content were genotype-specific, but commercially viable genotypes were identified that can provide genetic material for breeding programs and postharvest evaluation protocol for commercial use. [ABSTRACT FROM AUTHOR]

Previously, we have reported that consumption of a muscadine grape phytochemical powder (MGP) decreased lipid accumulation in high-fat fed mice. The aim of this study was to identify the responsible polyphenolic constituents and elucidate the underlying mechanisms. In mice, MGP supplementation significantly reduced visceral fat mass as well as adipocyte size. To determine whether MGP affects adipogenesis or hypertrophic lipid accumulation, we used a human adipogenic stem cell ( h ASCs) model. Among the MGP, ellagic acid (EA) was identified as a potent negative regulator of adipogenesis of h ASCs. In addition, EA substantially decreased the conversion of [ 3 H]-acetyl CoA into fatty acids (FAs), suggesting that EA inhibits de novo synthesis of FA in mature adipocytes. Similarly, MGP supplementation significantly decreased hepatic triglyceride (TG) levels. The TG-lowering effects of EA were confirmed in human hepatoma Huh7 cells. EA reduced [ 3 H]-oleic acid esterification into [ 3 H]-TG as well as the de novo synthesis of FA from [ 3 H]-acetyl CoA in Huh7 cells. Intriguingly, EA also increased oxygen consumption rate and β-oxidation-related gene expression. Taken together, EA attenuated new fat cell formation and FA biosynthesis in adipose tissue, while it reduced the synthesis of TG and FA and increased FA oxidation in the liver. These results suggest that EA exerts unique lipid-lowering effects both in adipose tissue and liver via discrete mechanisms. [ABSTRACT FROM AUTHOR]

The process of obtaining distant hybrids, as well as any crossing of cultivars of Vitis vinifera L. with representatives of species possessing the necessary qualities (resistance to diseases and pests, low temperature, etc.) may change the spectrum of chemical and biochemical compounds responsible for flavour, colour and taste of grapes, obtained juice and wine. Botanical description of distant hybrids was performed during all phases of the vegetative stages; the organs of the plants were studied from spring, at bud unfolding, until early autumn, at the fall of the leaves. For the determination of diglucoside-3,5-malvidin, the fluorimetric method, for determining the methyl anthranilate, the gas chromatographic method was applied. Based on the analyzes of biochemical constituents of grapes of the distant hybrids: DRX-M4-578; -502; -571; -660; -609; -580; etc., compared to the traditional cultivars „Feteasca albă" and „Rară neagră", it has been found that these varieties are similar. So, the distant hybrids of grapevine haven't inherited unwanted characters for vines, some of them are strictly limited (diglucoside-3,5-malvidol). These hybrids don't have the specific characteristics of direct production hybrids, characterised by the foxat taste of the grape berries, caused by the presence of the methyl anthranilate. The distant hybrids studied according to the classical uvologic and technological principles can be classified as follows: 5 distant hybrids are attributed to the table vine species and 2 distant hybrids have mixed properties. According to the physical and biochemical indices of the grapes of the studied distant hybrids, their characteristics are similar to European vine species. [ABSTRACT FROM AUTHOR]

A major limiting factor in fresh-market muscadine grape (Vitis rotundifolia Michx.) commercialization is fruit deterioration during storage. Research on table grapes has shown that field fungicide applications increase storability, but little is known of their effect on muscadines. The effect of field applications of fungicides on physicochemical attributes during postharvest storage and nutraceutical content at date of harvest was evaluated on five muscadine cultivars (Nesbitt, Southern Jewel, Summit, Supreme, and Tara) and four breeding selections from the University of Arkansas Fruit Breeding Program in 2012 and 2013. There were two field treatments (no fungicide and fungicide). For the fungicide treatment, alternating applications of two fungicides were applied to the vine at 14-day intervals during berry maturation. Fruit was harvested and physicochemical attributes including berry volume, titratable acidity (TA), pH, soluble solids (%), color (L, chroma, and hue), firmness (force to penetrate berry skins and flesh), storage weight loss (%), and unmarketable fruit (%) were evaluated every 7 days for 3 weeks. Whole muscadine berries were analyzed for nutraceutical content only for the date of harvest. As a result of less decay, less weight loss, and greater firmness during storage, AM 27, 'Southern Jewel', and 'Supreme' had the highest potential for postharvest storage, whereas AM 01, AM 15, and 'Tara' had the least potential. Nutraceutical content varied by genotypes; overall AM 27 had the highest nutraceutical content [sum of anthocyanins, total phenolics, flavonols, resveratrol, and oxygen radical absorbane capacity (ORAC)], whereas 'Supreme' and AM 28 had the lowest. Total anthocyanins were only found in the black genotypes and total phenolics and resveratrol were unaffected by fungicide treatment. Total ellagitannins varied among the fungicide treatments. Total flavonols were generally greater in the no fungicide treatments, whereas ORAC was generally greater with fungicide treatments. Year of study and genotype were determined to be major contributors as sources of variation. Although field fungicide applications did not affect all postharvest attributes and nutraceutical components, differences among genotypes and fungicide treatments did occur. [ABSTRACT FROM AUTHOR]

Wine is a kind of beverage with a variety of compounds beneficial to human health, which makes it popular all over the world and it contributes importantly to economics. The excessive oxidation of wine has always been a major problem in wine production and storage. Unlike traditional wines which are made from Eurasian grapes, wines made from muscadine grapes (Muscadinia rotundifolia Michx.) can maintain their sensory qualities under natural oxidation conditions for relatively long periods of time despite the insight mechanisms still being unclear. In this study, two muscadine wines, Carlos (CAL) and Noble (NOB), and two traditional wines, Chardonnay (CH) and Marselan (MAS), were chosen for comparison of their compositional alteration during oxidation, in order to analyze the principal components contributing to the antioxidant characteristics of muscadine wines. The DPPH, ORAC, color intensity, and total phenolic content changes during the natural oxidation process were analyzed. Six core significantly changed metabolites (SCMs, avicularin, beta-lactose, delphinidin-3-O-glucoside, ellagic acid, myricetin, and 4-methylcatechol [p < 0.05]) related to the oxidation process were determined. In addition, HPLC−MS was also used to identify pyrogallol which is a unique antioxidant compound in muscadine wine. The present work aims to reveal the crucial antioxidant compounds of muscadine wine and provide valuable information and a new platform for future research on wine oxidation.

Highlights: [•] This study comprehensively studied the enzymatic method of extracting muscadine grape skin and seed phenolics. [•] Combinations of solvent and enzyme, and treatment order greatly affected the release of grape phenolics. [•] Both enzymes and substrates should be considered to achieve an effective enzymatic hydrolysis for phenolics. [•] Enzymatic hydrolysis could modify the grape polyphenol profiles and release more potent antioxidant activity phenolics. [Copyright &y& Elsevier]

Ten grapevine cultivars were genotyped at eight microsatellite loci to characterize their identity and genetic diversity. Of these, nine cultivar profiles matched with those of databases and 'Magoon' matched with 'Regale' in the present study and 'Regale' in the University of California (Davis) database, implicating a likely error in planting. The number of alleles ranged from 5 (VVM5) to 9 (VVMD31), and the observed heterozygosity ranged from 37.14 (VVMD5) to 97.14% (VVMD27), with no significant differences in relation to the expected values for any of the loci, with the exception of VVMD5. The polymorphism information content values were observed to be above 0.25 in more than 85% of the loci analyzed, and VVMD31 was the most informative. The UPGMA analysis clustered the cultivars into two distinct groups. Within each group, the most divergent cultivars were 'Bountiful' (V. rotundifolia) and 'Goethe' (V. labrusca), also exhibiting the largest number of private alleles, 4 and 7, respectively. When comparing the two groups, the most divergent accessions were 'Bountiful' and 'Bordo', with the highest Nei distance. It was demonstrated that there is sufficient genetic variability in the cultivars used in this study to support breeding programs. [ABSTRACT FROM AUTHOR]

Inflammation and endoplasmic reticulum (ER) stress are common denominators for vision-threatening diseases such as diabetic retinopathy and age-related macular degeneration. Based on our previous study, supplementation with muscadine grape polyphenols (MGPs) alleviated systemic insulin resistance and proinflammatory responses. In this study, we hypothesized that MGPs would also be effective in attenuating ocular inflammation and ER stress. We tested this hypothesis using the human retinal pigmented epithelium (ARPE-19) cells and C57BL/6 mice. In ARPE-19 cells, tumor necrosis factor-a-induced proinflammatory gene expression of interleukin (IL)-1β, IL-6, and monocyte chemotactic protein-1 was decreased by 35.0%, 68.8%, and 62.5%, respectively, with MGP pretreatment, which was primarily due to the diminished mitogen-activated protein kinase activation and subsequent reduction of nuclear factor κ-B activation. Consistently, acute ocular inflammation and leukocyte infiltration were almost completely dampened (>95%) by MGP supplementation (100-200 mg/kg body weight) in C57BL/6 mice. Moreover, MGPs reduced inflammation-mediated loss of tight junctions and retinal permeability. To further investigate the protective roles of MGPs against ER stress, ARPE-19 cells were stimulated with thapsigargin. Pretreatment with MGPs significantly decreased the following: 1) ER stress-mediated vascular endothelial growth factor secretion (3.47 ± 0.06 vs. 1.58 ± 0.02 µg/L, P < 0.0001), 2) unfolded protein response, and 3) early apoptotic cell death (64.4 ± 6.85 vs. 33.7 ± 4.32%, P = 0.0003). Collectively, we have demonstrated that MGP is effective in attenuating ocular inflammation and ER stress. Our work also suggests that MGP may provide a novel dietary strategy to prevent vision-threatening retinal diseases. [ABSTRACT FROM AUTHOR]