Polymeric Procyanidins Research Articles

Cookies Fortified with Polyphenols Extracts: Impact on Phenolic Content, Antioxidant Activity, Inhibition of α-Amylase and α-Glucosidase Enzyme, Colour and Sensory Attractiveness.

The goal of the research was to determine the impact of fortification with polyphenolic compounds on (i) sensory attractiveness (global satisfaction, appearance, colour, odour, flavour, sweetness, bitterness), (ii) content of polyphenols and colour (L*, a*, b*) after the baking process and (iii) their bioactive potential (antioxidants activity and inhibiting of α-amylase and α-glucosidase enzyme). Fortification was made with extracts of polyphenolic compounds of selected plant raw materials rich in polyphenols from quince (fruits), tilia (flowers), pomegranate (skin), passion fruit (endocarp), sour cherries (leaves), haskap and chokeberry (berries), silver skin (coffee beans), rosehip (seeds). Depending on the nature of the polyphenol extract, flavan-3-ols (monomeric and polymeric), phenolic acid, flavonols and anthocyanins were identified in the product in amounts ranging from 53.7 to 212.6 mg/100 g DM. Cookies' colour (L*, a*, b*) depended on the type of polyphenol extract used for fortification. Cookies with haskap, chokeberry and sour cherry presented the highest antioxidant potential. Cookies with chokeberry, haskap and rosehip presented high activity in inhibiting α-amylase (65.5, 60.6 and 62.2% of inhibition, respectively), but cookies with haskap, silver skin and quince in inhibiting α-glucosidase activity (23.0, 20.4 and 21.4% of inhibition, respectively). In the sensory evaluation, the most attractive were cookies with rosehip and pomegranate (6.3 and 5.8 score, respectively), but the lowest ratings were given to cookies with passion fruit and silver skin but especially quince cookies, which obtained the lowest desirability (3.7 score). The acceptability of fortified cookies was determined to the least extent by monomeric flavan-3-ols and phenolic acids (in minus in odour/flavour, bitterness, sweetness and global satisfaction), but anthocyanins, polymeric procyanidins and flavonols had the most significant positive impact on consumer acceptance of the assessed features, i.e., global satisfaction, odour/flavour, sweetness and bitterness (positive consumer drivers).

Black and Red Currant Pomaces as Raw Materials to Create Smoothies with In Vitro Health-Promoting Potential.

Pomace is a by-product resulting from the pressing of fruits and vegetables into juices, and it is typically treated as waste. Interestingly, pomace contains minimal amounts of protein and fat but is characterized by its high polyphenol and dietary fiber contents, which may have health benefits for human physiology. Therefore, they are a potentially attractive raw material for the food industry, but to our knowledge, no smoothies with their addition have been prepared and described so far. Consequently, products derived from apple juice, incorporating different doses of fresh (6% and 12%) and dried (3% and 6%) black or red currant pomace, were formulated, and their physical properties, chemical composition, bioactive compound content, and health-promoting potential (in vitro antioxidant and antidiabetic activity) were evaluated. Additionally, the products underwent sensory assessment by consumers. The fortified beverages exhibited different physical characteristics and chemical compositions than apple juice. All smoothies were characterized by higher concentrations of anthocyanins, flavonols, and procyanidin polymers compared to the base product. Moreover, 75% of them exhibited a significantly elevated phenolic acid content as well as a higher concentration of flavan-3-ols. The majority of fresh smoothies exhibited significantly higher in vitro antioxidant capacities and increased in vitro α-amylase and α-glucosidase inhibitory effects compared to the base product. The highest ABTS activity was recorded in the variant with 6% dried black currant pomace. In turn, the smoothie with 3% dried red currant pomace had the most effective FRAP effect and, together with the product containing 12% fresh black currant pomace, ORAC antioxidant activity and α-glucosidase inhibition also. The introduction of 6% dried red currant pomace led to the creation of a beverage that most effectively inhibited α-glucosidase. The study showed that the application of various types of pomace, mainly that of black currant, into apple juice enables the development of new functional products with sensory attributes that are favorably evaluated by consumers.

Procyanidin B2-3'-O-Gallate Derived from Grape Seed Polymeric Procyanidins via the Galloyl-Attached Nucleophilic Degradation as a Potential Hepatoprotective Agent.

An effective method was developed for preparing galloylated procyanidins (GPCs) using galloyl-attached nucleophilic degradation. Under degradation conditions optimized through Box-Behnken design and single-factor experiments, two dimeric and three tetrameric GPCs were produced, with the yield of procyanidin B2-3'-O-gallate (B2-3'-G) reaching up to 232 mg/g (PPCs). The structure of B2-3'-G was identified by UV, FTIR, NMR, CD, MS, and phloroglucinolysis. Furthermore, the protective effect of B2-3'-G against alcohol-induced liver injury (ALI) was investigated. Compared with the parent compounds, B2-3'-G exhibited a stronger capacity for inhibiting ALI, attributed to its polymerization degree and galloyl group. Subsequent experiments revealed that the pretreatment of BRL-3A cells with B2-3'-G prior to ethanol improved ALI through activation of the Nrf2-HO-1/NQO1 pathway and initiation of enzymatic antioxidant systems. These findings suggest that GPC B2-3'-G is a potential hepatoprotective agent, which provides a new perspective for functional development of GPCs.

Review of the pharmacokinetics of French maritime pine bark extract (Pycnogenol®) in humans.

The French maritime pine bark extract Pycnogenol® is a proprietary product from Pinus pinaster Aiton. It complies with the quality specifications in the United States Pharmacopeia monograph "Pine extract" in the section of dietary supplements. Pycnogenol® is standardized to contain 65-75% procyanidins which are a variety of biopolymers consisting of catechin and epicatechin monomeric units. The effects of Pycnogenol® have been researched in a multitude of human studies. The basis for any in vivo activity is the bioavailability of constituents and metabolites of the extract. General principles of compound absorption, distribution, metabolism and elimination as well as specific data from studies with Pycnogenol® are summarized and discussed in this review. Based on plasma concentration profiles it can be concluded that low molecular weight constituents of the extract, such as catechin, caffeic and ferulic acid, taxifolin are readily absorbed from the small intestine into systemic circulation. Procyanidin oligomers and polymers are subjected to gut microbial degradation in the large intestine yielding small bioavailable metabolites such as 5-(3',4'-dihydroxyphenyl)-γ-valerolactone. After intake of Pycnogenol®, constituents and metabolites have been also detected in blood cells, synovial fluid and saliva indicating a substantial distribution in compartments other than serum. In studies simultaneously investigating concentrations in different specimen, a preferential distribution of individual compounds has been observed, e.g., of ferulic acid and 5-(3',4'-dihydroxyphenyl)-γ-valerolactone into synovial fluid compared to serum. The main route of elimination of constituents and metabolites of the French pine bark extract is the renal excretion. The broad knowledge accumulated regarding the pharmacokinetics of compounds and metabolites of Pycnogenol® constitute a rational basis for effects characterized on a cellular level and observed in human clinical studies.

Phenolic compounds in sea buckthorn (Hippophae rhamnoides L.) and their health‐promoting activities: a review

SummarySea buckthorn (SB) is used in cuisines and herbal remedies due to its remarkable nutritional composition and health‐enhancing properties. The phenolic compounds present in SB plant include phenolic acids (gallic, p‐coumaric, protocatechuic and ferulic acids), flavonols (isorhamnetin, quercetin and kaempferol), flavan‐3‐ols and polymeric procyanidins. The highest content of these compounds was reported in branches and leaves than corresponding edible parts of the plant. The antioxidant properties of SB are related to content and composition of phenolic compounds in different plant parts. The studies reported SB flavonoids (isorhamnetin and quercetin) as main phenolic compounds with medicinal potential and health‐promoting effects. The present review summarises information available in recent studies on phenolic composition, phenolic content, flavonoid content, antioxidant activity and health‐promoting activities (anti‐oxidant, hepatoprotective, cardioprotective, anti‐inflammatory, anti‐diabetic and obesity management) of SB that can be used in curtailing various acute and chronic maladies. SB can be projected as a promising source of bioactive constituents with the potential to be used in healthy foods for beneficial effects on human health.

Novel l-Cysteine Incomplete Degradation Method for Preparation of Procyanidin B2-3'-O-Gallate and Exploration of its in Vitro Anti-inflammatory Activity and in Vivo Tissue Distribution.

In this study, an effective method for preparation of bioactive galloylated procyanidin B2-3'-O-gallate (B2-3'-G) was first developed by incomplete depolymerization of grape seed polymeric procyanidins (PPCs) using l-cysteine (Cys) in the presence of citric acid. The structure-activity relationship of B2-3'-G was further evaluated in vitro through establishing lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. The results suggested that the better protective effects of B2-3'-G against inflammation were attributed to its polymerization degree and the introduction of the galloyl group, compared to its four corresponding structural units. In vivo experiments demonstrated that the B2-3'-G prototype was distributed in plasma, small intestine, liver, lung, and brain. Remarkably, B2-3'-G was able to penetrate the blood-brain barrier and appeared to play an important role in improving brain health. Furthermore, a total of 18 metabolites were identified in tissues. Potential metabolic pathways, including reduction, methylation, hydration, desaturation, glucuronide conjugation, and sulfation, were suggested.

The role of Arabic gum on astringency by modulating the polyphenol fraction-protein reaction in model wine.

The potential contribution of Arabic gum to wine astringency was discussed in this study. Two universally used Arabic gum (concentration of 0.2-1.2g/L) were investigated in model wine based on the polyphenol fractions (phenolic acids, monomeric/oligomeric, and polymeric procyanidin) and protein interaction system. Both physicochemical analyses and sensory evaluation revealed that the modulation of Arabic gum on astringency was affected by the structural properties and concentration of Arabic gum and polyphenolic fractions. Arabic gum at 0.2g/L appeared as the optimal dose to reduce astringency compared to 0.6 and 1.2g/L. It inhibited astringency induced by polymeric procyanidin more than that of oligomeric procyanidins and phenolic acids mainly by forming soluble ternary complexes with polyphenols and proteins, and preferentially binding proteins/polyphenols to decrease polyphenol-protein reactions. Arabic gum also inhibited the self-aggregation of polyphenols, exhibiting more binding sites when its higher molecular weight and more/longer branches, leading to competition with polyphenols for bind proteins.

Apple Pomace Compositional Data Highlighting the Proportional Contribution of Polymeric Procyanidins.

Recent years have seen an increase in research focusing on the amelioration of apple pomace waste for use in the food and nutraceutical industries. Much of this work has concentrated on the characterisation of the polyphenol composition of apple pomace materials to determine their role in conferring nutritional and health benefits. Although apples contain substantial quantities of polymeric procyanidins (condensed tannins), this class of compounds has received limited attention in apple research. This study quantified the polymeric procyanidins in apple pomace extracts using a rapid, methyl-cellulose precipitation (MCP) approach for the first time. In addition, a non-targeted metabolomics approach was applied to determine the most abundant phenolic classes present. Polymeric procyanidins were found to be the most abundant type of polyphenol in apple pomace extracts and were generally oligomeric in nature. Multivariate statistical analysis revealed that the ferric-reducing antioxidant power (FRAP) was most strongly correlated with the polymeric procyanidin concentration. Noting that polymeric procyanidins may not cross the cell layer to exert antioxidant activity in vivo, their presence in apple pomace extracts may therefore overestimate the FRAP. This work highlights the importance of polymeric procyanidins in the phenolic diversity of apple pomaces, and it is proposed that in future studies, rapid MCP assays may be used for their quantification.

Peach (Prunus persica (L.) Batsch) seeds and kernels as potential plant-based functional food ingredients: A review of bioactive compounds and health-promoting activities

Prunus persica (L.) Batsch (or peach) (Rosaceae) is the most important stone fruit crop in many areas, including North Africa, South Africa, and Europe. Peaches are well known for their flavor, nutritional value, and potential health benefits. During the consumption of peach fruit, usually jams, jellies, juices, and other food products, the seed and kernel (stone) is disposed of as waste. However, the seeds and kernels of peach fruit are considered remarkably rich sources of sodium, potassium, zinc, copper, iron, fatty acids (linolenic, oleic, palmitic, and linoleic acids), fiber, and carbohydrate (sucrose, glucose, and fructose) content. The preliminary results of various studies demonstrated that seed and kernels of peach fruit contain high amount of protein and bioactive peptides. Seed and kernels extract showed anti-ageing, anti-biofilm properties, protection against oxidative stress, cancer cell proliferation, inhibit type II diabetes, Alzheimer’s disease and obesity. It was concluded that biological properties are stimulated by the presence of hydroxycinnamic acids, polymeric procyanidins, cyanogenic glycosides, carotenoids and other metabolites. Oil extracted from the seeds of peach extracted via, supercritical CO2 shows the presence of phytosterols (stigmasterol, β-sitosterol, campesterol) that were widely known for their cholesterol-lowering effects, while additional research showed peach kernels as a potent source of phenolic compounds with high concentration of phenolic acids and catechin. Amygdalin is present in the seed extract of peach fruit, that changes into cyanide and supposed to kill cancer cells. A variety of studies are being conducted to recover possible bioactive compounds from peach seed and/or kernels in order to prevent environmental pollution and also economic losses. Thus, peach wastes, by-products, and their valorized compounds can be used as a sustainable resource of various important compounds that can be of great importance in different functional foods, pharmaceuticals, animal feed industry and cosmetics.

Inhibition of α-Amylase, α-Glucosidase, Pancreatic Lipase, 15-Lipooxygenase and Acetylcholinesterase Modulated by Polyphenolic Compounds, Organic Acids, and Carbohydrates of Prunus domestica Fruit.

This work aimed to establish the content of phenolic compounds, carbohydrates, and organic acids and to determine their potential to inactivate α-amylase, α-glucosidase, pancreatic lipase, 15-lipoxygenase (15-LOX), acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE), and antioxidant activity (ABTSo+ and FRAP) in 43 Prunus domestica cultivars. We identified 20 phenolic compounds, including, in the order of abundance, polymeric procyanidins, flavan-3-ols, phenolic acids, flavonols, and anthocyanins. The total content of phenolic compounds varied depending on the cultivar and ranged from 343.75 to 1419 mg/100 g d.w. The cultivars of Ś2, Ś11, and Ś16 accumulated the greatest amounts of polyphenols, while in cvs. Ś42, Ś35, and Ś20 polyphenols were the least abundant. The highest antioxidant potential of 7.71 (ABTSo+) and 13.28 (FRAP) mmoL Trolox/100 g d.w. was confirmed for cv. Ś11. P. domestica fruits showed inhibitory activity toward α-amylase (2.63-61.53), α-glucosidase (0.19-24.07), pancreatic lipase (0.50-8.20), and lipoxygenase (15-LOX; 4.19-32.67), expressed as IC50 (mg/mL). The anti-AChE effect was stronger than the anti-BuChE one. Cv. Ś3 did not inhibit AChE activity, while cv. Ś35 did not inhibit BuChE. Thanks to the abundance of biologically active compounds, P. domestica offers several health-promoting benefits and may prevent many diseases. For these reasons, they are worth introducing into a daily diet.

Oligomeric Proanthocyanidins: An Updated Review of Their Natural Sources, Synthesis, and Potentials.

Oligomeric Proanthocyanidins (OPCs), as a class of compounds widely found in plants, are particularly abundant in grapes and blueberries. It is a polymer comprising many different monomers, such as catechins and epicatechins. The monomers are usually linked to each other by two types of links, A-linkages (C-O-C) and B-linkages (C-C), to form the polymers. Numerous studies have shown that compared to high polymeric procyanidins, OPCs exhibit antioxidant properties due to the presence of multiple hydroxyl groups. This review describes the molecular structure and natural source of OPCs, their general synthesis pathway in plants, their antioxidant capacity, and potential applications, especially the anti-inflammatory, anti-aging, cardiovascular disease prevention, and antineoplastic functions. Currently, OPCs have attracted much attention, being non-toxic and natural antioxidants of plant origin that scavenge free radicals from the human body. This review would provide some references for further research on the biological functions of OPCs and their application in various fields.

Effect of Apple Juice Enrichment with Selected Plant Materials: Focus on Bioactive Compounds and Antioxidant Activity.

Using a multi-analytical approach, this paper aimed to investigate the effect of apple juice enrichment with Arbutus unedo and Diospyros kaki fruits, Myrtus communis berry extract, Acca sellowiana, or Crocus sativus flower by-products on both bioactive compounds content and antioxidant activity. Physico-chemical parameters, vitamin C, sugars, organic acids, total polyphenol content, antioxidant activity, and sensory attributes were evaluated. An LC-PDA/MS QTof analysis allowed for the identification of 80 different phenolic compounds. The highest polyphenol content (179.84 and 194.06 mg of GAE/100 g fw) and antioxidant activity (CUPRAC, 6.01 and 7.04 mmol of Fe2+/100 g fw) were observed in products with added A. sellowiana and D. kaki, respectively. Furthermore, the study showed a positive correlation between polymeric procyanidins and antioxidant activity (0.7646-0.8539). The addition of A. unedo fruits had a positively significant influence on the increment of vitamin C (23.68 ± 0.23 mg/100 g fw). The obtained products were attractive to consumers, especially those with 0.1% C. sativus flower juice, M. communis berry extract, and persimmon D. kaki fruits. The synergy among the different analytical techniques allowed us to obtain a complete set of information, demonstrating that the new apple smoothies were enriched in both different beneficial molecules for human health and in antioxidant activity.

Structure analysis and tyrosinase, melanogenesis, α-glucosidase, and nonenzymatic glycation inhibitory activities of polymeric proanthocyanidins from the pulp of Crataegus pinnatifida Bge.

Crataegus pinnatifida Bge. is a worthwhile industrial crop for its extensive application in Chinese herbal pharmaceuticals, food, and other industries. In this study, proanthocyanidins were extracted from the pulp of Crataegus pinnatifida Bge., and the structure, antityrosinase, antimelanogenesis, anti-α-glucosidase, and anti-glycation activities of these compounds were systematically elucidated. The combined utilization of high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), and nuclear magnetic resonance (NMR) demonstrated that the proanthocyanidins were B-type procyanidin polymers consisting of epicatechin . These polymers were efficient, reversible, and competitive inhibitors of both tyrosinase and α-glucosidase with IC 50 values of 0.10 ± 0.01 mg/mL (for monophenolase), 0.16 ± 0.02 mg/mL (for diphenolase), and 0.50 ± 0.02 µg/mL, respectively. Moreover, the process of nonenzymatic glycation was also delayed by proanthocyanidins. Further cell assays suggested that these polymers strongly inhibited intracellular tyrosinase activity and melanogenesis and induced apoptosis in mouse melanoma cells. The results of circular dichroism (CD), molecular docking , and molecular dynamics (MD) consistently revealed that the inhibition of procyanidins on the two enzymes was primarily driven by hydrogen bonding and hydrophobic interactions, and the binding of epicatechin caused structural stretching and conformational modification of tyrosinase. Consequently, this study confirms novel tyrosinase, melanogenesis, α-glucosidase, and nonenzymatic glycation inhibitors, which might offer scientific evidence for potential applications in the cosmetics and pharmaceutical industries. • Proanthocyanidins can be produced industrially for a yield of 11.08%. • Various biological activities of proanthocyanidins enabled their wide applications. • Hydrogen bond and hydrophobic interaction loosened tyrosinase secondary structures. • Proanthocyanidins can reduce melanogenesis by down-regulating tyrosinase proteins.

Characterisation and quantification of condensed tannins in rapeseed hulls and meals by depolymerization methods

Condensed tannins (i.e. polymerized procyanidins) were quantified in crude samples of rapeseed meal and hulls using two acidolysis methods. When it was applied directly on crude material, the colorimetric butanol-HCl assay allowed an estimation of two grams of tannins per kilogram of dried hulls. Interestingly, the estimation was more than double after solvent extraction using sodium dodecyl sulphate (SDS) when the colorimetric method was applied on both the extract and the insoluble residue. By altering the plant tissues organization, SDS treatment may allow a better accessibility of the depolymerizing reagents. However, this colorimetric assay was judged approximate because of browning side-reaction likely involving other components. Phloroglucinolysis combined with HPLC-UV-MS analysis was more rigorous and informative confirming that rapeseed hulls condensed tannins were essentially constituted of epicatechin units with an average degree of polymerization of close to 11. According to this method, the concentration of condensed tannins in hulls was estimated to 5.19 g/kg in the optimized conditions established through a factorial experimental design allowing optimization of hydrochloric acid concentration, reaction duration and temperature.

GRAPE BUNCH POLYPHENOLS, QUALITATIVE AND QUANTITATIVE COMPOSITION, TECHNOLOGICAL STOCK

The Magarach Institute has been addressing the issue of developing technologies for obtaining functional food products from grapes saturated with grape polyphenols; and of determining main properties and modes of grape polyphenol extraction from potential raw materials (pomace, seeds, crests) for the production of experimental samples of functional products. The aim of the present research was not only to experimentally determine the total stock of polyphenols in pomace, seeds, crests of red and white grape varieties, but also to assess empirically the qualitative and quantitative composition of total polyphenols in pomace, seeds, stems, vines, leaves of red and white grape varieties as functional components of a healthy nutrition. The research has dwelled upon the empiric assessment of the characteristics of grape raw materials (grape must, pomace, seeds, crests) in terms of their technological stock, quantitative and qualitative composition of polyphenols (by HPLC), and the main functional ingredients of the biological activity of grape products. An analysis of the data obtained shows that the aqueous-alcoholic extracts of grape raw materials possess the whole spectrum of polyphenols typical for red grape wines (anthocyanins, flavones, flavan-3-ols, hydroxycinnamic, hydroxybenzoic acids, stilbenes, oligomeric and polymeric procyanidins), however their concentration quantitatively exceeds that found in wines. It has been shown that the total content of water-soluble antioxidants experimentally determined by the amperometric method depends on the content of oligomeric and polymeric procyanidins in the extracts of grape raw materials. Thus, the content of oligomeric procyanidins in the extracts of grape raw materials from the sum of phenolic substances averaged 5.7%; while the content of polymer procyanides went up to 94%. The technological availability of polyphenols of pomace, stalks and grape seeds during water-alcohol extraction in the piled layer without mixing was shown, the equilibrium concentrations of polyphenols transferred into the extract and the potential amounts of polyphenols extracted during single-stage extraction (technological stock) were assessed. The maximum values of technological stock of polyphenols of 29.2–76.02 g/kg dry weight in the stalks of white and red grape varieties were determined.

Nuts as functional foods: Variation of nutritional and phytochemical profiles and their in vitro bioactive properties.

The aim of the present study was to examine the nutritional (fat, fatty acids, minerals, sugars) and bioactive compounds (polyphenols, tocochromanols, triterpene) and their influence on in vitro anti-diabetic (pancreatic α-amylase and intestinal α-glucosidase), anti-obesity (pancreatic lipase) and anti-cholinergic (AChE and BuChE) inhibitory activity of 8 different popular nuts-pecan, pine, hazelnuts, pistachio, almonds, cashew, walnuts, and macadamia. The total content of phenolic compounds in nuts ranged from 432.9 (walnuts) to 5.9 (pistachio) mg/100g. The dominant polyphenols are polymeric procyanidins (walnuts - 415.1mg/100g). Nuts are rich in tocochromanols (832.9-4377.5μg/100g), especially α- and γ-tocopherols. The highest content of α-tocopherol (vitamin E) was detected in hazelnuts and almonds (2551.0 and 2489.7μg/100g, respectively) while the lowest amounts were detected in macadamia, cashew and walnuts. The most abundant in nuts are oleanic and pomolic acids (35 and 22% of total, respectively), while betulin, uvaol and erythrodiol are less characteristic triterpenes for nuts (<1%). Pine nuts are the nuts with the highest content of triterpene (690.3mg/100g). Pistachio and almonds are the richest in total fat (>45%), but monounsaturated (17.5-79.3%; hazelnuts, almonds, cashew, macadamia, pistachio and pecan) and polyunsaturated (7.5-69.3%; pine, walnuts) are the dominant fatty acids. Moreover, nuts are low in Cu, Zn, Mn and Na content, but rich in K (464.5-1772.3mg/100g) and Mg (197.0-502.5mg/100g). Macadamia, walnuts and cashew are good sources of Se. Pistachio, almonds and cashew were characterized by the highest content of sugars, but the dominant sugar was saccharose (58.2-2399.3mg/100g). All nuts showed high activity in inhibiting intestinal α-glucosidase (>90%), but lower ability to inhibit pancreatic α-amylase and pancreatic lipase activity. The activity in inhibiting acetyl- and butylcholinesterase was up to 30%. As described above, all nuts contain various compounds that improve the nutritional value. Therefore they should be one of the important components of the daily human diet rich in functional foods.

Phytoconstituents of Red Grape Seeds Extract as Inflammatory Modulator in Adjuvant Arthritic Rats: Role Of IL-1 and its Receptor Blocking

This study focused on investigating the phytochemical composition of the total extract and the ethyl acetate fraction of red grape (Vitis vinifera L.) seeds as well as evaluating the total extract as anti-arthritis agents in rats compering with the new treating agent; interleukin-1 receptor antagonist (IL-1RA) and the classical anti-inflammatory drug; indomethacin. HPLC and LC-ESI-MS analysis was applied for identification and quantification the flavonoid and phenolic compounds. Arthritis was induced by using complete Freund’s adjuvant (CFA). The percentages of edema as well as the arthritis index were evaluated on the 7th, 14th, 21th and 28th day post CFA-induction. The evaluation was done by measuring serum interleukin-1 beta (IL-1β), IL-1 receptor type I gene expression, oxidative stress markers, intracellular adhesion molecule-1 (ICAM-1), caspase-3 (cas-3), c-reactive protein (CRP), prostaglandin E2 (PGE2), total protein content, DNA fragmentation, chromosomal aberration and cytogenic damage. The histopathological features of the ankle joint were analyzed. Stilbenes, phenolic acids, and anthocyanins were the major identified classes in the ethyl acetate fraction, while flavan-3-ol, oligomeric and polymeric procyanidins, flavonoid glucosides and phenolic acids were the main categories in the total extract. Three major proanthocyanidin compounds; gallic-4-O-β-glucopyranoside, catechin 3,5-di-O-gallate and catechin 3-O-gallate were identified in the ethyl acetate fraction. Treatment with seeds extract and IL-1RA improved the selected parameters by variable degrees. IL-1 RA showed a pronounced treating effect. In conclusion, Vitis vinifera seeds extract and IL-1RA are considered as promising anti-arthritis agents. More studies are required to conduct Vitis vinifera seeds extract and IL-1RA in pharmacological and clinical applications.

UPLC/ESI-Q-TOF-MS analysis of (poly)phenols, tocols and amino acids in Chaenomeles leaves versus in vitro anti-enzyme activities

The aim of this study was to investigate the content of phenolics, free amino acids, tocopherols, tocotrienols and in vitro biological activities (α-amylase, α-glucosidase, and pancreatic lipase inhibition activity) of 12 cultivars of Chaenomeles × superba, japonica and speciosa leaves. In the present work 39 phenolic compounds were tentatively identified, including polymeric procyanidins > flavan-3-ols > phenolic acids > flavonols > flavanones > flavones > ellagitannins. Chaenomeles leaves contained on average 16.8 g of phenolics per 100 g dry weight (dw), with C. × superba ˈNicolineˈ displaying the highest (27.5 g/100 g dw), and C. × superba ˈColour Trailˈ the lowest (7.7 g/100 g dw) total phenolic content. Chaenomeles leaves possess all eight tocol analogs (four tocopherols (TP), and four tocotrienols (TT)), ranked in decreasing content: α-TP > β-TP > γ-TP > δ-TP > α-TT > β-TT > δ-TT > γ-TT. The most active form (α-tocopherol) was present in amounts from 480.6 to 7201.1 µg/100 g dw. 23 amino acids were identified, including all nine essential amino acids. The highest amount of O-phospho-L-serine was found (average 249.2 mg/100 g dw). Leaves of C. japonica ˈRed Joyˈ displayed the highest total amino acid content (2735.2 mg/100 g dw). Chaenomeles leaves showed α-amylase (8.2–24.5 mg/mL), α-glucosidase (1.2-6.3 mg/mL), and pancreatic lipase (7.0-10.5 mg/mL) inhibition activity (expressed as half maximal inhibitory concentration, IC50). Chaenomeles leaves can be a good material for obtaining extracts rich in phenolics, vitamin E or amino acids, providing an alternative, natural source of these compounds to help meet the growing demand for nutraceuticals and supplements.

Chemical Diversity of Flavan-3-Ols in Grape Seeds: Modulating Factors and Quality Requirements.

Grape seeds are a rich source of flavan-3-ol monomers, oligomers, and polymers. The diverse profile of compounds includes mainly B-type procyanidins (especially C4→C8 linked molecules) and the key monomers, catechin, and epicatechin that are positively implicated in the ‘French Paradox’. Today grape seed nutraceuticals have become a multi-million-dollar industry. This has created incentives to elucidate the variations in chemistry across cultivars, to identify signs of adulteration, and to understand the intrinsic and extrinsic factors controlling the expression of metabolites in the seeds’ metabolome. This review provides a critical overview of the existing literature on grape seed chemistry. Although the biosynthetic pathways for polymeric procyanidins in seeds have not yet been explained, abiotic factors have been shown to modulate associated genes. Research of extrinsic factors has demonstrated that the control of procyanidin expression is strongly influenced, in order of importance, by genotype (species first, then variety) and environment, as claimed anecdotally. Unfortunately, research outcomes on the effects of abiotic factors have low certainty, because effects can be specific to genotype or variety, and there is limited control over physical metrics in the field. Thus, to gain a fuller understanding of the effects of abiotic factors and biosynthetic pathways, and realise potential for optimisation, a more fundamental research approach is needed. Nevertheless, the current synthesis offers insight into the selection of species or varieties according to the profile of polyphenols, as well as for optimisation of horticultural practices, with a view to produce products that contain the compounds that support health claims.

Investigating the effect of three phenolic fractions on the volatility of floral, fruity, and aged aromas by HS-SPME-GC-MS and NMR in model wine.

In this study, the volatility of three typical wine aromas in model wine was investigated by HS-SPME-GC-MS, NMR, and sensory evaluation as influenced by different concentrations and structural properties of phenolics. Results showed that three phenolic fractions (phenolic acids, monomeric/oligomeric and polymeric procyanidins) exhibited different matrix effects on floral, fruity, and aged aromas perception. Physico-chemical and sensory analyses together indicated that all fractions reduced the perceived intensity of fruity and aged aroma attributes, and displayed stronger retention effects on fruity aromas at higher mDP and concentrations. Monomeric/oligomeric and polymeric procyanidins promoted highly hydrophobic floral aromas release, whereas inhibiting the volatility of low hydrophobic fruity aromas. NMR confirmed that the reduction in the volatility of rose oxide, ethyl butanoate and whiskey lactone was attributed to interactions with epicatechin. This study aims to provide new thoughts and theoretical support for wine aroma regulation during winemaking by reconstructing the phenolic composition in wine.