Castalagin

Interaction between salivary proteins and cork phenolic compounds able to migrate to wine model solutions.[Pubmed:34388630]

Food Chem. 2022 Jan 15;367:130607.

This work reports the study of the interaction of human salivary proteins (SP) with phenolic compounds that migrate from cork stoppers to wine. This study yields valuable data to understand the influence that these compounds may have on the sensory perception of wine from an astringency perspective. For that, three cork fractions containing the phenolic compounds that migrate in greater amounts from cork to model wine solutions were selected. Fraction M1 contains gallic acid, protocatechuic acid, vanillin and protocatechuic aldehyde; fraction M2 comprises essentially gallic acid and ellagic acid, as well as Castalagin and dehydroCastalagin; and fraction M3 contains the two isomeric ellagitannins Castalagin and vescalagin. The reactivity of each fraction towards SP was M3 > M2 > M1. Within M3 fraction, Castalagin showed a higher ability to precipitate SP (mainly aPRPs, statherin and P-B peptide) comparatively to vescalagin. In M1 fraction, caffeic and sinapic acids were the compounds with the highest interaction with SP, mainly cystatins. In addition, there also seems to be a matrix effect (presence of other compounds) that could be affecting these interactions.

Pharmacological investigation of antioxidant and anti-inflammatory activities of leaves and branches extracts from Plinia cauliflora (Jaboticaba).[Pubmed:34352328]

J Ethnopharmacol. 2021 Nov 15;280:114463.

ETHNOPHARMACOLOGICAL RELEVANCE: Among all native Brazilian plant species, Plinia cauliflora (DC.) Kausel (Jaboticaba), is well known for producing "superfruits", due to their high phenolic content and antioxidant property. The fruit has astringent characteristics, and it is popularly known for the treatment of diarrhea, rash, and intestinal inflammation. However, there are only a few studies on the use of leaves and branches of this species in the literature, mainly to treat oxidative stress and inflammation. AIM OF THE STUDY: The present study aimed to investigate the antioxidant and anti-inflammatory potential of leaves and branches extracts from P. cauliflora. MATERIAL AND METHODS: The phytochemical analysis of P. cauliflora extracts was performed by the total phenolic, flavonoid, and tannin dosage method. Moreover, the compounds were identified by HPLC-MS-Q-TOF. Antioxidant capacity was determined by DPPH, beta-carotene/linoleic acid system, MDA formation, and phosphomolybdenum assays. In vitro and in vivo anti-inflammatory activities of P. cauliflora were evaluated by the reduction of nitric oxide in the J774A.1 cell line and inhibition of ear edema in mice, respectively. RESULTS: The ethanolic extract of the leaves exhibited greater flavonoid content whereas the ethanolic extract of the branches showed higher tannins content. Twenty-two and seventeen compounds were identified by HPLC-MS-Q-TOF in the leaves and branches, respectively, being tellimagrandin I, Castalagin, and valoneic acid dilactone reported for the first time in P. cauliflora. The antioxidant potential of extracts was confirmed through different oxidation pathways from oxidizing radicals, which might be related to the presence of phenolic compounds. For the anti-inflammatory assay, the leaves and branches extracts showed promising results, with a reduction of nitric oxide ear edema inhibition around 95% and 80%, respectively. CONCLUSIONS: Herein, the great biological potential of leaves and branches extracts from P. cauliflora was highlighted. These parts of the plant are underused and poorly reported in the literature, especially for the antioxidant and anti-inflammatory activities.

Two new C-glycosidic ellagitannins and accompanying tannins from Lawsonia inermis leaves and their cytotoxic effects.[Pubmed:33984438]

Fitoterapia. 2021 Sep;153:104925.

Investigation on tannins having antitumor properties led to the isolation of two new C-glycosidic ellagitannins (1 and 2) along with seven known ellagitannins (3-9) and a related polyphenolic constituent (10) from Lawsonia inermis leaves. Our intensive HRESIMS, 1D and 2D NMR, and ECD spectroscopic studies of new tannins have shown that one (1) has a monomer structure of C-glycosidic tannin, and the other (2) has a dimeric structure of 2,3-O-hexahydroxydiphenoyl glucopyranose and a C-glycosidic tannin. Among the known compounds, one (3) is a C-glycosidic tannin that was isolated first of all from nature, five were C-glycosidic tannins, vescalagin (4), 1-O-methylvescalagin (5), Castalagin (6), stachyurin (7), and casuarinin (8), and one was an O-glycosidic ellagitannin, tellimagrandin II (9). The remaining phenolic constituent from the leaves was identified as valoneic acid dilactone (10). The ellagitannins 1, and 3-9 demonstrated noticeable cytotoxicity on human oral squamous cell carcinoma cell lines (HSC-2, HSC-4, and Ca9-22), and lower effects on human oral normal cells (HGF, HPC, and HPLF). Tellimagrandin II (9) had the highest tumor-specific cytotoxicity, and also cleaved poly (ADP-ribose) polymerase 1 in HSC-2 cells. These findings showed that L. inermis ellagitannins may be a candidate for the production of anti-oral cancer materials.

Identification and quantification of phenolic composition from different species of Jabuticaba (Plinia spp.) by HPLC-DAD-ESI/MS(n).[Pubmed:33799238]

Food Chem. 2021 Sep 1;355:129605.

The aim of this study was to investigate phenolic compounds in peel, pulp and seeds of five different jabuticabas - Plinia trunciflora, "cabinho", P. cauliflora, cultivars "paulista" and "canaa-acu", P. jaboticaba, "sabara" and P. phitrantha, "branca-vinho". In addition to the commonly reported cyanidin-3-glucoside and delphinidin3-glucoside, it was also found the unreported cyanidin-3-coumaroylglucoside in the peels. Flavonols derived from quercetin and myricetin were also detected in jaboticaba peels, along with a wide variety of derivatives of ellagic acid and methyl ellagic acid. The latter derivatives occurred in acylated forms, which were not usually found in jabuticabas. The pulps and seeds of jabuticabas contained large amounts of ellagitannins vescalagin and Castalagin, as well as gallic and ellagic acids. The jabuticabas showed small amounts of catechin and gallocatechin. P. jaboticaba showed the highest levels of anthocyanins and flavonols derived from myricetin, and P. phitrantha presented the highest concentration of ellagitannins and flavan-3-ols.

Correction: Vescalagin and castalagin reduce the toxicity of amyloid-beta42 oligomers through the remodelling of its secondary structure.[Pubmed:33729246]

Chem Commun (Camb). 2021 Mar 28;57(25):3158.

Correction for 'Vescalagin and Castalagin reduce the toxicity of amyloid-beta42 oligomers through the remodelling of its secondary structure' by Ana R. Araujo et al., Chem. Commun., 2020, 56, 3187-3190, DOI: .

Vescalagin and Castalagin Present Bactericidal Activity toward Methicillin-Resistant Bacteria.[Pubmed:33596039]

ACS Biomater Sci Eng. 2021 Mar 8;7(3):1022-1030.

Polyphenols have been extensively exploited in the biomedical field because of their wide range of bioactive properties and historical use as traditional medicines. They typically present antioxidant, antimicrobial, antiamyloidogenic, and/or antitumor activities. In particular, cork water extracts and their components, have been previously reported to present antioxidant and antiamyloidogenic properties. On the basis of this knowledge, we tested cork water extract (CWE), cork water enriched extract (CWE-E), vescalagin/Castalagin (two of the main polyphenols present in CWE and CWE-E) for their antibacterial activity against four bacterial strains, namely, methicillin-resistant Staphylococcus epidermidis (MRSE), Staphylococcus aureus (SA), methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa (PA). Vescalagin and Castalagin presented bactericidal activity against all the tested bacterial strains, in particular toward the methicillin-resistant ones, i.e., MRSA and MRSE, as well as the ability to inhibit the formation of biofilms and to disrupt preformed ones. Moreover, vescalagin/Castalagin seem to modulate the normal assembly of the peptidoglycans at the bacteria surface, promoting the disruption of their cell wall, leading to bacterial cell death. We also demonstrate that vescalagin/Castalagin can be loaded into alginate hydrogels to generate antibacterial biomaterials that are not toxic to eukaryotic cells.

Variation in the Phenolic Composition of Cork Stoppers from Different Geographical Origins.[Pubmed:33274939]

J Agric Food Chem. 2020 Dec 16;68(50):14970-14977.

Cork stopper granulates from five geographical origins from Portugal and six from Spain were analyzed regarding polyphenol composition by HPLC-DAD/ESI-MS and geographical discrimination studied by near-infrared spectroscopy (NIRS). The phenolic composition of the eleven origins ranged from 30 to 52 mg/g cork granulates, with vescavaloninic acid, Castalagin, sanguisorbic acid dilactone, vescalagin, castavaloninic acid, dehydrated tergallic-C-Glc, and ellagic acid being the major compounds. NIRS revealed to be a powerful tool to discriminate origins and predict the concentration of polyphenols. However, polyphenols do not fully explain the discrimination of geographical origins. Variability in the polyphenol composition of cork stoppers is not significantly influenced by geographical location but probably may be more related to the plant genetics, tree age, and phytosanitary and edaphoclimatic conditions.

Generation Times of E. coli Prolong with Increasing Tannin Concentration while the Lag Phase Extends Exponentially.[Pubmed:33271746]

Plants (Basel). 2020 Dec 1;9(12). pii: plants9121680.

The current study examines the effect of tannins and tannin extracts on the lag phase duration, growth rate, and generation time of Escherichia coli. Effects of Castalagin, vescalagin, gallic acid, Colistizer, tannic acid as well as chestnut, mimosa, and quebracho extracts were determined on E. coli's growth phases using the broth microdilution method and obtained by turbidimetric measurements. E. coli responds to the stress caused by the investigated antimicrobial agents with reduced growth rates, longer generation times, and extended lag phases. Prolongation of the lag phase was relatively small at low tannin concentrations, while it became more pronounced at concentrations above half the MIC. Moreover, for the first time, it was observed that lag time extensions follow a strict exponential relationship with increasing tannin concentrations. This feature is very likely a direct consequence of the tannin complexation of certain essential ions from the growth medium, making them unavailable to E. coli for its growth.

Lythrum salicaria Ellagitannins Stimulate IPEC-J2 Cells Monolayer Formation and Inhibit Enteropathogenic Escherichia coli Growth and Adhesion.[Pubmed:33270444]

J Nat Prod. 2020 Dec 24;83(12):3614-3622.

Lythrum salicaria herb (LSH) was applied in diarrhea therapy since ancient times. Despite empirically referenced therapeutic effects, the bioactivity mechanisms and chemical constituents responsible for pharmacological activity remain not fully resolved. Taking into consideration the historical use of LSH in treatment of diarrhea in humans and farm animals, the aim of the study was to examine in vitro the influence of LSH and its C-glycosylic ellagitannins on processes associated with maintaining intestinal epithelium integrity and enteropathogenic Escherichia coli (EPEC) growth and adhesion. LSH was not only inhibiting EPEC growth in a concentration dependent manner but also its adhesion to IPEC-J2 intestinal epithelial cell monolayers. Inhibitory activity toward EPEC growth was additionally confirmed ex vivo in distal colon samples of postweaning piglets. LSH and its dominating C-glycosylic ellagitannins, Castalagin (1), vescalagin (2), and salicarinins A (3) and B (4) were stimulating IPEC-J2 monolayer formation by enhancing claudin 4 production. Parallelly tested gut microbiota metabolites of LSH ellagitannins, urolithin C (5), urolithin A (6), and its glucuronides (7) were inactive. The activities of LSH and the isolated ellagitannins support its purported antidiarrheal properties and indicate potential mechanisms responsible for its beneficial influence on the intestinal epithelium.

Validation of a mass spectrometry method to identify and quantify ellagitannins in oak wood and cognac during aging in oak barrels.[Pubmed:33069531]

Food Chem. 2021 Apr 16;342:128223.

Ellagitannins are the main extractible phenolic compounds in oak wood; the monomers vescalagin and Castalagin, lyxose/xylose-bearing monomers grandinin and roburin E, dimers roburins A and D and lyxose/xylose-bearing dimers roburins B and C are the principal ones. These compounds are responsible for the high durability of wood and may contribute to the organoleptic quality of wines and spirits (color, astringency, bitterness). Despite their importance, their presence and forms in distilled spirits are not well known. The aim of this work was therefore to develop and validate a method to identify and quantify oak wood ellagitannins in Cognac using high liquid chromatography-triple quadrupole (LC-QQQ) analysis. The method was validated using vescalagin as the standard and by studying sensitivity, linearity in working range, intraday repeatability, and intraday precision in order to quantify individual ellagitannins in this complex matrix.

New insights into the phenolic compounds and antioxidant capacity of feijoa and cherry fruits cultivated in Brazil.[Pubmed:32846605]

Food Res Int. 2020 Oct;136:109564.

Acca sellowiana (feijoa) and Eugenia involucrata (cherry) are fruits species of Brazilian biodiversity (Myrtaceae family). In this study, a sampling process was used with three different harvesting sites. The composition of phenolic compounds of these fruits was determined by HPLC-DAD-MS/MS. Moreover, the antioxidant capacity of hydroethanolic extracts against hydrogen peroxide (H2O2), hydroxyl (OH), peroxyl (ROO(-)) and ABTS radicals was evaluated. Thirty and twenty-seven phenolic compounds were identified in feijoa and cherry, respectively. The major phenolic compounds found were pedunculagin isomer (5040.87, 3443.66 and 1324.95 mug.g(-1)) in feijoa and procyanidin (1406.54, 1888.00 and 1380.64 mug.g(-1)) in cherry. Hydroethanolic extract of these fruits was a potent scavenger of free radicals and excellent source of phenolic compounds. In hydroethanolic extracts of feijoa, the phenolic content increased by around 50%, while in the cherry the content was similar to that found in the fruit. For ORAC method, sample 2 of feijoa and cherry showed values of 383 and 126 microM.TE.g(-1), respectively, featuring the highest antioxidant capacity. This study is the first to report the identification of Castalagin, catechin and epicatechin in feijoa, and rutin in cherry. Besides, the health benefits, these fruits can contribute to biodiversity conservation.

Polyphenols of jabuticaba [Myrciaria jaboticaba (Vell.) O.Berg] seeds incorporated in a yogurt model exert antioxidant activity and modulate gut microbiota of 1,2-dimethylhydrazine-induced colon cancer in rats.[Pubmed:32717686]

Food Chem. 2021 Jan 1;334:127565.

The chemical composition, antioxidant activity (AA), cytotoxic activity, antihemolytic effects, and enzyme inhibition (EI) of lyophilized jabuticaba (Myrciaria jaboticaba) seed extract (LJE) was studied. The main compounds found were Castalagin, vescalagin, procyanidin A2, and ellagic acid. LJE was more toxic to cancer cells than to normal cells, meaning relative toxicological safety. This cytotoxic effect can be attributed to the pro-oxidant effect observed in the reactive oxygen species (ROS) generation assay. LJE inhibited alpha-amylase, alpha-glucosidase, and ACE-I activities and protected human erythrocytes from hemolysis. LJE was incorporated into yogurts at different concentrations and the total phenolic content, AA, and EI increased in a dose-dependent manner. LJE-containing yogurt presented 86% sensory acceptance. The yogurt was administered to Wistar rats bearing cancer and it modulated the gut bacterial microbiota, having a prebiotic effect. LJE is a potential functional ingredient for food companies looking for TPC, AA, and prebiotic effect in vivo.