Grape Flesh Research Articles

Influence of Grape Flesh on the Retention and Composition of Polyphenols from Skins and Seeds.

This study examined the impact of grape flesh polysaccharide, protein, and amino acid contents on polyphenol retention from skins and seeds in Pinot noir (Vitis vinifera) and cold-hardy interspecific cultivars Marquette and Frontenac (Vitis spp.). After isolating grape tissues (skin, seed, and flesh), they were soaked either individually or combined with other tissues in a wine-like solution for up to 7 days. Findings revealed that flesh significantly reduces the concentration of condensed tannin, and mono- and diglucoside forms of anthocyanins in the supernatants, due to its rich content in polysaccharides and proteins. Frontenac skin and flesh tissues were the main sources of soluble proteins, amino acids, and soluble polysaccharides. Surprisingly, Marquette exhibited a higher retention of skin tannin than Pinot noir, likely due to its smaller tannin molecular mass, and a potential competitive effect with anthocyanins for the binding sites of flesh.

Impacts of Selenium–Chitosan Treatment on Color of “Red Globe” Grapes during Low-Temperature Storage

Maintaining the vibrant color of fruit is a longstanding challenge in fruit and vegetable preservation. Chitosan and selenium, known for their protective and antioxidant properties, have been applied to preserve these produce. This study aimed to investigate the influence of selenium–chitosan treatment (comprising 25 mg L−1 selenium and 1.0% chitosan) on the color of “Red Globe” grapes and to analyze the relative expression of genes associated with anthocyanin synthesis enzymes (VvCHS, VvCHI, VvF3H, VvF3′H, VvF3′5′H, VvDFR, VvLDOX, VvUFGT, VvOMT, Vv5GT, and VvGST) using RT-qPCR. Our goal was to uncover the regulatory mechanisms governing grape color. Comparing various treatments, we observed that selenium–chitosan treatment had a significant effect in reducing decay, maintaining the soluble solids content of grape flesh, and preserving the vivid color of grape. This research indicated that selenium–chitosan treatment slowed down browning and prevented the reduction in total phenolic, flavonoids, and anthocyanin in the grape. Moreover, gene expression analysis revealed that selenium–chitosan treatment increased the expression of VvCHS, VvF3H, VvF’3′H, VvLDOX, and Vv5GT, while also stabilized the expression of VvCHI, VvF3′H, and VvDFR in grape skins. These findings shed light on the potential mechanism by which selenium–chitosan impacts grape color. This study established a theoretical foundation for investigating the molecular mechanisms behind selenium–chitosan’s ability to slow down grape browning and provides a novel approach to enhancing fruit and vegetable preservation techniques.

Transcriptome analysis reveals the mechanism of ‘ZhongShan-HongYu’ grape anthocyanin accumulation

During the biosynthesis of anthocyanin, the protein encoding GST transports anthocyanins synthesized in the endoplasmic reticulum to the vesicle, resulting in plant coloration. ‘ZhongShan-HongYu’ (ZS-HY) is a new teinturier germplasm which accumulates anthocyanin in the skin and flesh of the fruit. However, the molecular mechanisms of the flesh coloration in ‘ZS-HY’ remains unclear. We analyzed the transcriptomic profiles of ‘ZS-HY’ and ‘Zico’ flesh (‘ZS-HY’ and ‘Zico’ have similar phenological periods) at 5, 6 and 7 days after anthesis (DAA) using RNA-sequencing technology. A total of 76.27 G of clean data were obtained from our RNA-seq. By analyzing the differentially expressed genes (DEGs) in the flesh, 212 genes potentially involved in anthocyanin biosynthesis were screened. Through further analysis of DEGs, the genes related to anthocyanin accumulation in grape flesh, including VvMYBA1 and VvGST4, were selected for gene function verification. Subcellular localization analysis revealed that VvMYBA1 and VvGST4 were located in cytoplasm and nucleus. The interaction between VvMYBA1 and VvGST4 was analyzed by yeast two-hybrid analysis and BiFC assay. Meanwhile, we found that VvMYBA1 can regulate the activity of VvGST4 promoter by binding with it. Our study provides a basis for the molecular mechanism of anthocyanin transport in grape.

Integrated metabolomic and transcriptomic analysis reveals the mechanism underlying the accumulation of anthocyanins and other flavonoids in the flesh and skin of teinturier grapes

Vitis vinifera ‘Yan73’ is a teinturier grape cultivar with red flesh. To explore the mechanism of berry color development, we performed an integrated flavonoid-targeted analysis of the metabolome and transcriptome of the skin and flesh of Yan73 berries collected at three phenological stages (E-L 31, E-L 35, and E-L 38). We identified 234 flavonoid-related metabolites, including 61 flavonols, 22 anthocyanins, and 61 other flavonoids. Most flavonoid metabolites accumulated continuously during berry development and attained the highest contents in the skin at E-L 38. The transcript level of crucial genes (C4H, CHS, and GST) was highest in the skin at E-L 38. Seventeen distinct modules were identified in a weighted gene correlation network analysis. The MEcoral1 module was probably correlated with flavonoid metabolism and comprised 623 unigenes. The findings provide insights into the regulation of flavonoid metabolites during berry development of Yan73 grape.

Characterization of anthocyanin and nonanthocyanidin phenolic compounds and/or their biosynthesis pathway in red-fleshed ‘Kanghong’ grape berries and their wine

This study determined the composition and content of anthocyanin compounds in red-fleshed ‘Kanghong’ (KH) berries and wine and revealed the anthocyanin biosynthesis pathway in KH flesh. The 41 anthocyanin compounds detected primarily accumulated in KH skin, followed by flesh and seeds. Anthocyanin compounds with a single glucoside, particularly malvidin-3-O-glucoside, were the most abundant components in KH berries. The percentage of anthocyanin compounds was altered in KH flesh compared to KH skin. KH berries and their wine contained a much higher anthocyanin content than Cabernet Sauvignon (CS) wine. Additionally, a total of 48 differentially accumulated nonanthocyanin phenolic compounds and 2104 differentially expressed genes between KH and CS flesh were identified, and their association analysis indicated that the metabolic flux of phenolic compounds in the phenylpropanoid pathway was promoted in KH flesh. Therefore, this work elucidated the accumulation characteristics of anthocyanins in KH berries and provided the mechanism underlying grape flesh coloration.

Anthocyanins Absorption of Grapes (Vitis vinifera) on Filter Paper Whatmann No. 41 and Whatmann No. 42 for Identification of Borax

Borax detection can be done using the flame test method, volumetric titration, spectrophotometric analysis, and qualitatively using natural materials such as curcumin and anthocyanins. The high content of anthocyanins in grapes has the potential to be utilized in acid-base titrations as an indicator of natural acid-base. The research objective was to determine the potential of anthocyanins in the flesh and skin of grapes in detecting natural borax which is absorbed on filter paper, Whatmann paper no. 41 and Whatmann paper no. 42. Then it was tested on samples of meatballs from 5 sellers in Samarinda Seberang to Mangkupalas village. The research method used is a quantitative analysis of the color changes that occur. Based on the research results, filter paper can have a better absorption that is shown with a dark color on Whatmann No. 41 and Whatmann No.42. Grape skin extract can detect borax more clearly than flesh by forming a dark purple ring when reacting with borax. In testing using meatball samples, the overall results showed that the samples contained borax. It was concluded that the filter paper from the absorption of grape skin anthocyanins could be used as an alternative in quantitatively testing the borax content in food.

Comparative Learning Curves of Microscope Versus Exoscope: A Preclinical Randomized Crossover Noninferiority Study.

BackgroundAn exoscope heralds a new era of optics in surgery. However, there is limited quantitative evidence describing and comparing the learning curve.ObjectivesThis study aimed to investigate the learning curve, plateau, and rate of novice surgeons using an Olympus ORBEYE exoscope compared to an operating microscope (Carl Zeiss OPMI PENTERO or KINEVO 900).MethodsA preclinical, randomized, crossover, noninferiority trial assessed the performance of seventeen novice and seven expert surgeons completing the microsurgical grape dissection task “Star’s the limit.” A standardized star was drawn on a grape using a stencil with a 5 mm edge length. Participants cut the star and peeled the star-shaped skin off the grape with microscissors and forceps while minimizing damage to the grape flesh. Participants repeated the task 20 times consecutively for each optical device. Learning was assessed using model functions such as the Weibull function, and the cognitive workload was assessed with the NASA Task Load Index (NASA-TLX).ResultsSeventeen novice (male:female 12:5; median years of training 0.4 [0–2.8 years]) and six expert (male:female 4:2; median years of training 10 [8.9–24 years]) surgeons were recruited. “Star’s the limit” was validated using a performance score that gave a threshold of expert performance of 70 (0–100). The learning rate (ORBEYE −0.94 ± 0.37; microscope −1.30 ± 0.46) and learning plateau (ORBEYE 64.89 ± 8.81; microscope 65.93 ± 9.44) of the ORBEYE were significantly noninferior compared to those of the microscope group (p = 0.009; p = 0.027, respectively). The cognitive workload on NASA-TLX was higher for the ORBEYE. Novices preferred the freedom of movement and ergonomics of the ORBEYE but preferred the visualization of the microscope.ConclusionsThis is the first study to quantify the ORBEYE learning curve and the first randomized controlled trial to compare the ORBEYE learning curve to that of the microscope. The plateau performance and learning rate of the ORBEYE are significantly noninferior to those of the microscope in a preclinical grape dissection task. This study also supports the ergonomics of the ORBEYE as reported in preliminary observational studies and highlights visualization as a focus for further development.

Impact of the variety on the adsorption of anthocyanins and tannins on grape flesh cell walls.

During winemaking, after extraction from the skins, anthocyanins and tannins adsorb onto the pulp flesh cell walls. The present study aimed to quantify the amounts adsorbed and their impact on wine composition, the impact of variety and ethanol on adsorption, and whether the presence of anthocyanins plays a role and impacts tannin adsorption. Anthocyanin and tannin fractions obtained by mimicking winemaking conditions were mixed with fresh flesh cell walls of two varieties: Carignan and Grenache. Adsorption isotherms were measured. Adsorption of tannins was higher with Carignan than with Grenache and decreased when the ethanol content increased. In comparison, anthocyanins were adsorbed in small amounts, and their mixing with tannins had no impact on their adsorption. The differences were related to differences in pulp cell wall composition, particularly in terms of extensins and arabinans. Adsorption of tannins, which can reach 50% of the initial amount, depends on the pulp cell wall composition. This needs to be investigated further. © 2021 Society of Chemical Industry.

Anthocyanin degradation and the underlying molecular mechanism in a red-fleshed grape variety

Red wine grape color and quality decrease substantially at the late stages of ripening in warm climates because of anthocyanin degradation; however, the underlying mechanism remains unclear. We analyzed the anthocyanin metabolite and transcriptome profiles of Yan73 grape berries from two vintages using HPLC-ESI-MS/MS and RNA-sequencing technologies. The results showed that anthocyanins in Yan73 grape skin and flesh were significantly degraded at the late stages of ripening in both vintages. Moreover, non-methylated anthocyanins were degraded at a higher rate than the methylated anthocyanins. The protocatechuic acid (i.e., possible anthocyanin degradation product) concentration increased significantly in Yan73 skin and flesh at the late stages of ripening. However, the expression of anthocyanin biosynthesis-related structural genes and MYBA1 was upregulated in Yan73 skin and flesh at the late stages of ripening, indicating an increase in the anthocyanin synthesis capacity. Enzyme activity and qRT-PCR assays revealed that peroxidase and polyphenol oxidase activities and the VvPrx31 expression level increased in Yan73 skin and flesh at the late stages of ripening, suggesting they may function in the anthocyanin degradation. The β-glucosidase activity was higher only in Yan73 grape flesh at the late stages of ripening. These findings clarify the pre-harvest anthocyanin degradation in grape berries.

Coordinated Regulation of Grape Berry Flesh Color by Transcriptional Activators and Repressors.

Yan73 is a teinturier Vitis vinifera variety with red berry flesh, but the molecular mechanisms underlying its flesh coloration remain unclear. We analyzed the flavonoid metabolic and transcriptome profiles of Yan73 berry red and white flesh using HPLC-ESI-MS/MS and RNA-sequencing technologies. Anthocyanins are the main flavonoids responsible for Yan73 berry flesh color, and the coloration is coordinately regulated by the VvMYBA1 transcriptional activator and VvMYBC2-L1 transcriptional repressor. Furthermore, yeast one- and two-hybrid, dual luciferase, and bimolecular fluorescence complementation assays suggested that VvMYBA1 positively regulates Yan73 berry flesh color via interactions with VvWDR1 and the activation of the VvCHI3, VvOMT, and VvGST4 promoters, whereas VvMYBC2-L1 negatively regulates Yan73 berry flesh color, possibly by competing with the R2R3-MYB transcriptional activators for bHLH partners or by repressing VvOMT and VvGST4 expression. Our findings provide new insights into the molecular mechanisms regulating grape flesh color.

Quantitative Proteome Analysis Reveals Changes in the Protein Landscape During Grape Berry Development With a Focus on Vacuolar Transport Proteins.

The vacuole plays a central role in fruit growth and quality formation, yet its proteomic landscape is largely unknown. In the present study, a protocol for isolating intact vacuoles from grape flesh tissue was successfully established. Quantitative proteome analysis identified 2533 proteins from five sampling dates along Cabernet Sauvignon berry development from stage I to III; among them, 1443 proteins were identified on all five sampling dates in at least two biological replicates per sample and were designated core proteome, and 1820 were recruited as differentially abundant proteins (DAPs) by sequential pairwise comparisons using arbitrary fold change of >1.5 and P < 0.05. Metabolism consistently constituted the largest category of identified proteins for both core proteome and DAPs, together with a consistently high proportion of protein-fate category proteins, indicating that the classic lytic functions of vegetative cell vacuoles are maintained throughout berry development; accumulation of metabolites involved in high sugar and other berry qualities in the late developmental stage added to the conventional lytic role of the flesh cell vacuoles. Overall increases in abundance of the DAPs were seen in the transporter proteins, membrane fusion/vesicle trafficking, and protein-fate categories, and decreased abundance was seen for DAPs in the stress, energy and cytoskeleton categories as berry development progressed. A very pronounced proteomic change was revealed between late stage I and mid stage II, with 915 increased and 114 decreased DAPs, demonstrating a significant surge of the vacuolar proteome underlying the rather static phenotypical and physiological phase. We identified 161 transport proteins with differential abundance, including proton pumps, aquaporins, sugar transporters, ATP-binding cassette transporters and ion transport proteins, together with organic compound transport proteins, the highest number and variety of berry tonoplast transporters found in grape proteome efforts to date. We further found a pre-positive increment of 96 transport proteins from the middle of stage II, before the berry undergoes its dramatic physiological changes at and following véraison. Our results are the first to describe the proteome of a vacuole-enriched preparation, toward understanding the functions of the largest compartment in berry cells during grape growth and ripening.

In vitro antioxidant activity of Kyoho grape extracts in DPPH[rad] and ABTS[rad] assays: Estimation methods for EC50 using advanced statistical programs

The antioxidant capacities of Kyoho skin, seed, and flesh extracts were determined using DPPH and ABTS assays and a suitable statistical program was tested for the prediction of EC50 values of Kyoho skin, seed, and flesh extracts obtained by DPPH and ABTS assays. Statistical programs: OriginPro® version 8, GraphPad Prism® version 7, GraphPad Prism® version 7 five-parameter (5P) logistic model, SigmaPlot® version 14.0, Microsoft Excel® version 2016, interpolation log, and direct interpolation methods were employed to estimate the EC50 values. Linear regression and direct interpolation results showed deviations for non-linear models in the prediction of EC50 values of grape extracts. The correlation results of grape flesh extracts demonstrated a positive correlation (r = ≥ 0.95) between EC50 values of antioxidant assays. Therefore, non-linear methods were appropriate for EC50 calculations. These findings have significant implications for selecting an efficient statistical tool to calculate EC50 values for DPPH and ABTS assays.

Changes of Anthocyanin Component Biosynthesis in 'Summer Black' Grape Berries after the Red Flesh Mutation Occurred.

The coloring process of grape flesh is valuable for research and promotion of the high nutritional quality of anthocyanins. 'Summer Black' and it is new red flesh mutant were used to analyze the changes of anthocyanin biosynthesis during grape berry development. Eighteen kinds of anthocyanins were detected in mature berries of the two cultivars, but the content of most 3'- and 3',5'-substituted anthocyanins was higher in the skin of the mutant. Anthocyanin accumulation occurred simultaneously in the skin and flesh of the mutant, and their types and content were more abundant in the former. For the mutant, there were only CHS, OMT, MYBA3, and MYBPA1 at lower transcriptional level in the flesh during veraison when compared with these in the skin, which might be an important factor to limit the anthocyanin accumulation in the flesh. The occurrence of red flesh might be related the enhancement of anthocyanin biosynthesis in the whole berry.

Endophytic fungi specifically introduce novel metabolites into grape flesh cells in vitro.

Since endophytes can affect metabolism of host plants, they are expected to be used to improve crop quality, especially for crops with organoleptic sensitive products such as wine grape. However, details of metabolic interactions between endophytes and host plants were less understood. In this work, we used high pressure liquid chromatography (HPLC) to analyze the metabolites of fruit flesh cells of grape treated with dual culture of different endophytic fungal strains (EFS). We observed that the dual-culture with different fungal strains show different metabolites composition in grape cells. In response to different EFS, quantities of detected metabolites in grape cells varied from 6 to 17 in this assay, and 1 to 11 novel metabolites were introduced into metabolome of grape cells. Dual-culture with fungal strains CS2, RH16 and RH5 introduced the highest quantities (10 or 11) of novel metabolites in grape cells. More importantly, the modification of metabolic profiles in grape cells via fungal endophytes appeared to be fungal strain/genus-specificity. Overall, this work revealed that introduction of specific metabolites in host plants may be one consequence during the process of endophytes-host metabolic interactions, which raise the possibility to shape grape qualities and characteristics using tool of fungal endophytes.

Antioxidant activities of fresh grape juices prepared using various household processing methods.

The purpose of this study was to evaluate and compare the antioxidant activities, and their contents, in grape juices prepared by various household juicers, and grape flesh (GF). The grape juices were prepared using a low-speed masticating (LSM) juicer, a high-speed centrifugal (HSC) juicer, and a blender (BLD). The total polyphenol, total flavonoid, total monomeric anthocyanin, and vitamin C contents were highest in the LSM grape juice, and decreased in the order: LSM>BLD>HSC>GF. The antioxidant activities such as DPPH radical scavenging activity, and SOD-like activity were significantly higher in the LSM juice than in other juices and grape flesh. The antioxidant activities and the quality of grape juices were significantly affected by the household juicing method used, and an LSM juicer is strongly recommended for making healthy grape juice, rich in antioxidants.

Table grape of Ukraine – varietal resources, pers­pectives of production and consumption

Purpose. To enrich and improve the range of table grape varieties of Ukraine. Methods. Breeding, hybridological, mathematic, visual ones. Results. Modern Ukrainian gene pool of table grape varieties has been created on the base of the best introduced and homegrown cultivars and selections. New genotypes that are creating at the National Scientific Centre “Institute of Viticulture and Wine-Making named after V. Ye. Tairov” under the breeding program “Resistense plus Quality” are the basis of current and future regional assortments for the south and central areas of the steppe zone of Ukraine. The complexity of the origine explains the genetically determined high-level manifestation of commercially valuable characters. New varieties and selections are ecologically safe for humans and the environment, as the level of their resistance to the group of fungal main diseases is not less than 6.5 points according to the 9-point scale, therefore they do not require a large pesticide load. New promising table varieties demonstrate a stable yield and high marketability of grapes – 5–10 kg per plant with the marketability nearly 80–87% during the last five years. In addition, dense flesh of grapes is a guarantee of high transportability. The variety of table genotypes taste, shape and berries ripening from very early to very late embodied in the innovative and highly profitable development “Conveyor of table grapes”. Depending on the ecological and geographical conditions, the conveyor can include a diffe­rent quantity of varieties, but to in order increase the efficiency and profitability it is necessary to have a few groups (from 2 to 4 varietes) of different ripening. The approximate ratio (%) of varieties of different ripening time is recommended: very early – 22%, early – 22%, average – 17%, mid-late – 17%, and late – 22%. Conclusions. The variation of shape, flavour and color of new promising genotypes of table grapes makes them very popular on the market and may satisfy the most demanding consumer. The stability of the adaptive and technological traits makes the new table varieties very attractive for the producers of grape products.

Protective role of extracts of grape skin and grape flesh on ethanol-induced oxidative stress, inflammation and histological alterations in rat brain

Ethanol consumption has deleterious effects on all organs and especially on brain. In our study, the radical scavenging properties of grape skin and grape flesh (contains natural antioxidants like polyphenols) was determined in vitro and for in vivo studies, male Wistar rats (16–18 week-old) and 100–120 gm weight were divided in five groups of six animals each. One group were fed with ethanol (1.6 gm/kg body weight), while second group were fed with ethanol (1.6 g/kg body weight) and grape skin extract (2.5 g/kg body weight), the third group were fed with ethanol (1.6 g/kg body weight) and grape flesh extract, daily once for 12 weeks, while the fourth group were fed with ethanol (1.6 g/kg body weight) and tocopheryl acetate (80 mg/kg/day) daily once for 12 weeks. Results of in vitro studies indicate that grape skin extracts showed significant radical scavenging properties (ROS). There was also significantly alteration of serum cytokines in our study.

Study on the Pathogens Carrier Rate of “Red Globe” Table Grape at Different Temperatures

“Red Globe” table grapes were packaged at four temperature conditions: -1C、-0.5C、0C and 4C. Pathogens carrier rate of grape flesh, grape pedicel, grape peduncle and disease incidence rate were measured at 0, 15, 30, 45, 60, 75 and 90 days. The result revealed that-0.5C was the best storage condition of “Red Globe” table grape, from perspective of pathogens carrier rate of grape flesh, grape pedicel, grape peduncle and disease incidence rate. There was a positive correlation between disease incidence rate and pathogens carrier rate of grape parts. This study is to provide a theoretical basis for reducing the loss red grapes.

Hydro- and thermotimes for conidial germination kinetics of the ochratoxigenic species Aspergillus carbonarius in vitro, on grape skin and grape flesh

The objective was to compare the ability of spores of Aspergillus carbonarius to germinate in vitro, in situ on grape skin and grape flesh in relation to temperature (15–40 °C) and different relative humidities (100–85 % RH). Spores were inoculated as a spore suspension (106 spores ml−1) onto the surface of white organic grapes and directly onto cut grape flesh. For comparison, spores were spread plate onto a synthetic grape juice medium (SGM) modified to the equivalent water activity (aw) range of 0.995–0.85. This showed that conidia germinated more rapidly on grape flesh (6 h) followed by that on the SGM medium (9 h) and then grape skin (24 h) under optimal condition of 30–35 °C and 100 % RH. At marginal conditions, such as 15 °C and 85–90 % RH, germination was very slow. The time to 5 % germination was significantly shorter on grape flesh than in vitro on grape medium and slowest on grape skin. This suggests that damaged grapes provide the main method of infection and contamination of grapes and grape products with ochratoxin A (OTA). The combined effect of temperature and RH on conidial germination of A. carbonarius on SGM and grape skin was described by combining Beta and polynomial equations. The equations developed in this work provided a good fit of the biological processes; they could be integrated in a predictive model for infection and OTA prediction in ripening grapes.

Measurement and analysis of mineral and heavy metal components in grape cultivars by inductively coupled plasma-optical emission spectrometer (ICP-OES)

Mineral and heavy metal in grape flesh of different cultivars were measured by inductively coupled plasma-optical emission spectrometer. Eight grape varieties including four wine grapes (Cabernet Sauvignon, Cabernet Franc, Merlot, Cabernet Gernischt) and four table grapes (Muscat, Red Globe, Vitis labruscana Kyoho, Milk grape) from China’s main grape planting region, Changli, Hebei province were investigated. Concentrations of calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), lead (Pb) and zinc (Zn) were measured. All the parameters investigated in this study significantly changed depending on the cultivar. The minor and heavy metal levels for grape were determined between 5.68 and 15.11 mg/kg Cr, 6.56 and 19.85 mg/kg Cu, 96.79 and 172.15 mg/kg Fe, 6.54 and 25.23 mg/kg Mn, 3.70 and 5.89 mg/kg Ni, 0 and 1.64 mg/kg Pb and 4.29 and 13.44 mg/kg Zn. K ranged from 7,622.87 to 15,276.51 mg/kg and Na concentration ranged from 8,932.82 to 54,343.4 mg/kg. Cadmium was not detected at all.