Role of Pterostilbene in Metabolic Diseases through SIRT1 pathway- A Review

Pterostilbene (PTE) (3-5 dimethoxy-4-hydroxy-trans-stilbenes) is an analogue of resveratrol. It is extracted and isolated from a natural source of the heartwood of Pterocarpus marsupium Roxb., red grape skin, and blueberries (Vaccinium spp.). Substantial evidence suggested that PTE displayed numerous preventive and therapeutic properties in many metabolic disorders such as diabetes and obesity. Metabolic diseases result in Insulin resistance (IR) which advances to impaired sensitivity to insulin-mediated glucose disposal. The prominent role of SIRT (silent information regulator proteins) is now getting emphasized in metabolic disorders. SIRT1 represses Uncoupling protein 2 (UCP2) expressions which are further responsible for improving synthesis of ATP from glucose. This results in improving glucose utilization and insulin secretion, thus preventing IR. SIRT1 also exhibits prominent role in facilitating fatty acid mobilization thereby inhibiting adiposity. Metabolic disorders are therefore the consequences of SIRT1 downregulation. Pterostilbene, being a SIRT1 activator, increases insulin sensitivity reduces adiposity, therefore can prove to be beneficial in diabetes as well as obesity. The review summarizes therapeutic effects portrayed by Pterostilbene via the SIRT1 pathway in metabolic diseases.

Thermal Stability and Inhibitory Action of Red Grape Skin Phytochemicals against Enzymes Associated with Metabolic Syndrome

The present study focuses on heat-induced structural changes and the degradation kinetics of phytochemicals and antioxidant activity of red grape skin extract. The thermal degradation of anthocyanins, flavonoids, polyphenols, and antioxidant activity followed a first-order kinetic model, increasing with temperature due to the intensification of the degradation process. The activation energy (Ea) highlighted this phenomenon. Likewise, the kinetic and thermodynamic parameters certified the irreversible degradation of the bioactive compounds from the skin of the Băbească neagră grape variety. Both temperature and duration of heating had a significant impact on the content of bioactive compounds. In addition, the red grape skin extract inhibited certain enzymes such as α-amylase, α-glucosidase, lipase, and lipoxygenase, which are associated with metabolic syndrome and inflammation. Further knowledge on the possible inhibition mechanisms exerted by the major anthocyanins found in red grape skin extract on the metabolic syndrome-associated enzymes was gathered upon running molecular docking tests. Detailed analysis of the resulting molecular models revealed that malvidin 3-O-glucoside binds in the vicinity of the catalytic site of α-amylase and lipase, whereas no direct contact with catalytic amino acids was identified in the case of α-glucosidase and lipoxygenase.

Renoprotection of Selected Antioxidant-Rich Foods (Water Spinach and Red Grape) and Probiotics in Gentamicin-Induced Nephrotoxicity and Oxidative Stress in Rats

Objectives: The current study investigated the curative effects of two selected antioxidant-rich foods (water spinach and red grape) and probiotics on the kidney exposed to nephrotoxicity induced by gentamicin. Methods: A total of 30 Wistar Albino female rats equally divided into six groups were studied for seven days. Except for the normal control (NC) group, all groups received 80 mg/kg/day gentamicin (GEN) injection intra-peritoneally for seven days. NC and GEN groups received only regular diet. In the water spinach group (GEN + WS) and red grape (GEN + RG) groups, rats were provided with 20 g/rat/day of boiled water spinach and 5 mL/rat/day of red grape juice, respectively. The probiotic (GEN + P4) and (GEN + P8) groups received 4 × 109 and 8 × 109 viable bacteria, respectively. On the 8th day, all the rats were sacrificed to collect blood and kidney. Serum creatinine, urea, uric acid, malondialdehyde (MDA), nitric oxide (NO), and superoxide dismutase (SOD) were analyzed. In addition, kidney histopathology was taken for final observation. Results: Both antioxidant-rich foods and probiotic (P4) significantly (p < 0.05) attenuated the GEN-induced oxidative and nitrosative stress and improved kidney function by lowering uremic toxin (serum creatinine, and uric acid) levels. Histopathological findings of kidney tissues of all groups were consistent with the biochemical findings. Conclusion: The current preclinical study suggests that the consumption of antioxidant-rich foods might be a promising fighting option against gentamycin-induced nephrotoxicity and oxidative stress. However, extensive studies and clinical monitoring are immediately required to determine the appropriate probiotic doses and mechanism of action for such effects.

Determining the pectinesterase enzyme activity when storing table grape varieties depending on the degree of ripening

Grapes are rich in easily digestible carbohydrates, mineral compounds, vitamins, phenolic compounds. and other vital components. It is known that fresh grapes can be used from September to December. To prolong the terms of consumption of this valuable raw material, the most appropriate varieties and conditions for storing grapes have been determined. White, pink, and red grape varieties were taken as the object of research. The changes in the activity of the pectinesterase enzyme were determined depending on the degree of ripening of table grape varieties, the change in the pectinesterase enzyme during storage of table grape varieties in various variants was investigated. Statistical processing and calculation of variations in the indicators of changes in the activity of the enzyme pectinesterase were performed, depending on the degree of ripening of grapes of the Shamakhi Marandi variety. During the study, the pectinesterase enzyme remained more stable in mature varieties. This means that in ripe table grape varieties, the absorption of nutrients in the respiratory process is significantly slowed down. However, as they mature, the activity of the pectinesterase enzyme gradually increases. Therefore, for long-term storage in refrigerated chambers, fully ripe varieties of table grapes were used; to this end, grapes of the white Ganja table variety, the pink Shamakhi Marandi variety, and the red Black Asma variety are more suitable. The comparison of the investigated variants showed that table grape varieties, when stored in a refrigerated chamber in a controlled atmosphere, at 3–4 % CO2 and 2–3 % O2, retain better quality than other variants. When storing table grape varieties of various variants in the refrigerator, the enzyme activity decreases but is not completely suppressed.

Yeast and Filamentous Fungi Microbial Communities in Organic Red Grape Juice: Effect of Vintage, Maturity Stage, SO2, and Bioprotection

Changes are currently being made to winemaking processes to reduce chemical inputs [particularly sulfur dioxide (SO2)] and adapt to consumer demand. In this study, yeast growth and fungal diversity were investigated in merlot during the prefermentary stages of a winemaking process without addition of SO2. Different factors were considered, in a two-year study: vintage, maturity level and bioprotection by the adding yeast as an alternative to SO2. The population of the target species was monitored by quantitative-PCR, and yeast and filamentous fungi diversity was determined by 18S rDNA metabarcoding. A gradual decrease of the α-diversity during the maceration process was highlighted. Maturity level played a significant role in yeast and fungal abundance, which was lower at advanced maturity, while vintage had a strong impact on Hanseniaspora spp. population level and abundance. The presence of SO2 altered the abundance of yeast and filamentous fungi, but not their nature. The absence of sulfiting led to an unexpected reduction in diversity compared to the presence of SO2, which might result from the occupation of the niche by certain dominant species, namely Hanseniaspora spp. Inoculation of the grape juice with non-Saccharomyces yeast resulted in a decrease in the abundance of filamentous fungi generally associated with a decline in grape must quality. Lower abundance and niche occupation by bioprotection agents were observed at the overripened stage, thus suggesting that doses applied should be reconsidered at advanced maturity. Our study confirmed the bioprotective role of Metschnikowia pulcherrima and Torulaspora delbrueckii in a context of vinification without sulfites.

Bilberry/red grape juice decreases plasma biomarkers of inflammation and tissue damage in aged men with subjective memory impairment –a randomized clinical trial

Background Few randomized clinical trials have explored the health effects of bilberries in humans. The aim was to test the effect of bilberry and red grape-juice consumption on visual memory, motor speed and dexterity as well as inflammatory and tissue damage biomarkers of plasma in aged men with subjective memory impairment. Methods Nine-week double-blind, placebo-controlled, dietary intervention study of aged men (n = 60, age ≥ 67 years) with subjective memory impairment randomized to consume a 50/50 mix of bilberry/red grape-juice or an iso-caloric placebo juice. A selection of Cambridge Cognition Test Battery (CANTAB), Grooved Pegboard tests and blood-sampling for biomarker analysis were performed before and after the intervention. Results Compared to placebo the selected memory and motor test scores were un-affected by the bilberry/red grape intervention. However, the plasma levels of tissue damage biomarkers decreased significantly more in the bilberry/red grape group. In particular lactate dehydrogenase (LDH) decreased from 362 U/L (median, baseline) to 346 U/L (median, post intervention) in the bilberry/red grape group. Also, several biomarkers of inflammation (EGF, IL6, IL9, IL10 and TNFα) decreased significantly more in the bilberry/red grape group. Furthermore, several plasma polyphenols; p-coumaric acid, hippuric acid, protocatechuic acid, 3HPAA and vanillic acid, increased significantly more in the bilberry/red grape group compared to placebo with the largest increase in p-coumaric acid with 116%; from 2.2 [1.0,5.5] to 4.7 [2.8,8.1] μM/L (median [95% CL]). Conclusions The results indicate that a nine-week bilberry/red grape juice intervention has no measurable effects on the selected memory scores in aged men experiencing memory problems but decreases the level of biomarkers of inflammation and tissue damage. Whether the dampening effects on inflammation and tissue damage biomarkers have relevance for neuroinflammatory brain pathology remains to be established. Trial registration Registration number (ClinicalTrials.gov: NCT00972972), September 9, 2009.

SwinGD: A Robust Grape Bunch Detection Model Based on Swin Transformer in Complex Vineyard Environment

Accurate recognition of fruits in the orchard is an important step for robot picking in the natural environment, since many CNN models have a low recognition rate when dealing with irregularly shaped and very dense fruits, such as a grape bunch. It is a new trend to use a transformer structure and apply it to a computer vision domain for image processing. This paper provides Swin Transformer and DETR models to achieve grape bunch detection. Additionally, they are compared with traditional CNN models, such as Faster-RCNN, SSD, and YOLO. In addition, the optimal number of stages for a Swin Transformer through experiments is selected. Furthermore, the latest YOLOX model is also used to make a comparison with the Swin Transformer, and the experimental results show that YOLOX has higher accuracy and better detection effect. The above models are trained under red grape datasets collected under natural light. In addition, the dataset is expanded through image data augmentation to achieve a better training effect. After 200 epochs of training, SwinGD obtained an exciting mAP value of 94% when IoU = 0.5. In case of overexposure, overdarkness, and occlusion, SwinGD can recognize more accurately and robustly compared with other models. At the same time, SwinGD still has a better effect when dealing with dense grape bunches. Furthermore, 100 pictures of grapes containing 655 grape bunches are downloaded from Baidu pictures to detect the effect. The Swin Transformer has an accuracy of 91.5%. In order to verify the universality of SwinGD, we conducted a test under green grape images. The experimental results show that SwinGD has a good effect in practical application. The success of SwinGD provides a new solution for precision harvesting in agriculture.

Effect of dietary red grape pomace on growth performance, hematology, serum biochemistry, and meat quality parameters in Hy-line Silver Brown cockerels

Red grape (Vitis vinifera L.) pomace’s (RGP) beneficial bioactive compounds could improve growth and meat quality traits in chickens and thus valorize RGP waste that is usually disposed in landfills to the detriment of the environment. This study investigated the effect of RGP inclusion in diets of Hy-line Silver Brown cockerels on physiological and meat quality responses. Five isonitrogenous and isocaloric diets were formulated by mixing a standard grower diet with RGP at 0 (G0), 15 (G15), 30 (G30), 45 (G45) and 60 g/kg (G60). A total of 250, 5-week-old cockerels (304.6 ± 6.57 g live-weight) were evenly allocated to 25 pens replicated 5 times per experimental diet. No linear and quadratic trends (P > 0.05) were observed for overall feed intake, body weight gain, feed conversion ratio, and meat quality traits as dietary RGP levels increased. Erythrocytes linearly decreased (P < 0.05), whereas mean corpuscular hemoglobin and urea linearly increased (P < 0.05) with RGP levels. There were significant quadratic effects for glucose, phosphorus, total protein, albumin, globulin, and cholesterol, from which a maximum RGP inclusion level was calculated to be 43 g/kg. In conclusion, dietary red grape pomace had no adverse effect on physiological parameters and meat quality traits of Hy-line Silver Brown cockerels. However, including red grape pomace beyond 43 g/kg could compromise serum biochemical parameters of the birds.

Workflow to Investigate Subtle Differences in Wine Volatile Metabolome Induced by Different Root Systems and Irrigation Regimes

To allow for a broad survey of subtle metabolic shifts in wine caused by rootstock and irrigation, an integrated metabolomics-based workflow followed by quantitation was developed. This workflow was particularly useful when applied to a poorly studied red grape variety cv. Chambourcin. Allowing volatile metabolites that otherwise may have been missed with a targeted analysis to be included, this approach allowed deeper modeling of treatment differences which then could be used to identify important compounds. Wines produced on a per vine basis, over two years, were analyzed using SPME-GC-MS/MS. From the 382 and 221 features that differed significantly among rootstocks in 2017 and 2018, respectively, we tentatively identified 94 compounds by library search and retention index, with 22 confirmed and quantified using authentic standards. Own-rooted Chambourcin differed from other root systems for multiple volatile compounds with fewer differences among grafted vines. For example, the average concentration of β-Damascenone present in own-rooted vines (9.49 µg/L) was significantly lower in other rootstocks (8.59 µg/L), whereas mean Linalool was significantly higher in 1103P rootstock compared to own-rooted. β-Damascenone was higher in regulated deficit irrigation (RDI) than other treatments. The approach outlined not only was shown to be useful for scientific investigation, but also in creating a protocol for analysis that would ensure differences of interest to the industry are not missed.

Incorporation of Natural Blueberry, Red Grapes and Parsley Extract by-Products into the Production of Chitosan Edible Films

The aim of the research was to produce edible packaging based on chitosan with the addition of various concentrations of extracts of blueberry, red grape and parsley marcs. Packaging was made from extrudate extracts, which were subsequently analyzed by physicochemical methods: zeta-potential, gas barrier properties, thickness, water content, solubility, swelling degree, textural properties, total polyphenol content (TPC), polyphenols by high pressure liquid chromatography (HPLC), antioxidant activity, attenuated total reflectance Fourier-Transform spectroscopy (FTIR), antimicrobial activity and determination of migration of bioactive substances. The results indicate that a higher content of plant extracts have a statistically significant (p < 0.05) influence on properties of experimentally produced edible films. Edible films produced with the highest concentrations of red grapes marc extracts showed the most advantageous properties since antimicrobial activity against E. coli were the highest in this kind of produced film. The physical properties of edible films were also improved by the addition of extracts; gas permeability toward oxygen can be defined as advantageous, as can swelling degree, which decreased with higher concentrations of extracts. The research emphasized the possibility to use plant foodstuffs by-products in the production of edible/biodegradable films, helping in the overall sustainability and eco-friendliness of food/package production.