Fingerprinting of anthocyanins from grapes produced in Brazil using HPLC–DAD–MS and exploratory analysis by principal component analysis

Stability of anthocyanin extracts from chokeberry, grape, hibiscus, and purple sweet potato in ω-3-fatty acid rich oil-in-water emulsions

The food industry is actively investigating the stability of natural red pigments to replace artificial food colorants from all food applications in the near future. In this study, the stability of coloring extracts from chokeberry, grape, hibiscus, and purple sweet potato was investigated in ω-3 fatty acid-rich flaxseed oil-in-water emulsion during storage. The red color of the oil-in-water emulsions faded within 4 days, indicating that the anthocyanin extracts were susceptible to lipid oxidation reactions of the ω-3 fatty acids. The color stability varied between all used extract sources: The chokeberry (degradation constant k = 19.6 h-1) and grape (k = 15.2 h-1) extracts showed similar degradation kinetics, whereas purple sweet potato extract (k = 10.7 h-1) degraded significantly slower, and hibiscus extract (k = 110.2 h-1) significantly faster. The differences can be explained by the different anthocyanins contained in the plant extract, especially by the proportion of acylated anthocyanins.

Ultrasound-assisted extraction of anthocyanins from grape pomace using acidified water: Assessing total monomeric anthocyanin and specific anthocyanin contents

This study aimed to optimize the ultrasound-assisted extraction (UAE) of anthocyanins from oven-dried and freeze-dried Vitis labrusca grape pomace, using acidified water as the solvent. The effects of power density (8.3-16.7 W/mL), pulse interval (0-2 s), and extraction time (1-5 min) on both total and specific anthocyanins were investigated. The findings suggested that acidified water can be a viable alternative to conventional solvents and that oven drying was an effective method for drying the pomace. Using response surface methodology, the study identified power density and extraction time as key factors influencing total anthocyanin content, with extracts reaching contents up to 2.56 mg/g. The analysis using LC-MS identified 14 anthocyanins, while NMR quantified 3 and malvidin diglucoside was generally the most abundant. However, higher power and longer extraction times were found to reduce its content while increasing malvidin monoglucoside content, suggesting ultrasound-induced anthocyanin hydrolysis. In conclusion, this study presents a sustainable method for extracting anthocyanins using acidified water, contributing to the valorization of Vitis labrusca grape pomace for industrial use.

Exploration of the anthocyanin and proanthocyanidin profile of Greek red grape skins belonging to Vradiano, Limnio, and Kotsifali cultivars, analyzed by a novel LC-QTOF-MS/MS method

INTRODUCTION

Winegrape varieties Kotsifali, Limnio, and Vradiano OBJECTIVE: The aim of this study was to develop a liquid chromatographic quadrupole time-of-flight tandem mass spectrometric (LC-QTOF-MS/MS) method for the investigation of the anthocyanin and proanthocyanidin content of Greek grape varieties employing target and suspect screening strategies.

METHODOLOGY

A novel LC-QTOF-MS/MS method was developed and validated to assess the anthocyanin content of Kotsifali, Limnio, and Vradiano grape varieties. Sixteen grape samples were collected from the main growing areas of each variety in Greece. The influence of the grape variety on the anthocyanin and proanthocyanidin composition of three Greek winegrapes was investigated using chemometrics.

RESULTS

Excellent linearity (R2 > 0.99) was achieved for all the target analytes, and recoveries ranged between 90.1% and 119.1%. The limits of quantification (LOQs) and limits of detection (LODs) were calculated over the range of 0.020-0.40 mg/g and 0.010-0.13 mg/g, respectively. The RSD% was lower than 9.1% and 7.3% for intra-day and inter-day studies, respectively, indicating satisfactory trueness and precision. Target and suspect screening resulted in the identification of 5 and 26 anthocyanins, respectively.

CONCLUSIONS

Kotsifali variety exhibited a higher concentration of anthocyanins compared with Vradiano and Limnio. Higher levels of mean degree of polymerization (mDp) and different percentage levels of prodelphinidins (%P) were established among the varieties.

Chemical characterization, multivariate analysis and comparison of biological activities of different parts of Fraxinus mandshurica

Fraxinus mandshurica (Oleaceae) is used as a traditional medicinal plant for the treatment of red eyes, menstrual disorders, excessive leucorrhea, chronic bronchitis and psoriasis. To perform chemical characterization of the secondary metabolites of F. mandshurica roots, bark, stems and leaves, 32 samples were collected from eight provinces in this study. A total of 64 chemical components were detected from four different parts of F. mandshurica by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Meanwhile, a total of nine secoiridoids were obtained by natural product chemical extraction, isolation and identification methods. Quantitative analysis by high-performance liquid chromatography-diode array detection-mass spectrometry showed the highest total content of secoiridoids in the bark, which is also consistent with the traditional medicinal parts. The results of methodological validation showed that the correlation coefficient (R2) values were all >0.9993, indicating a good linear range of the standard curve, while the relative standard deviations of precision, reproducibility and stability were <3%, and the spiked recoveries ranged from 98.22 to 102.27%, indicating that the experimental method was reliable and stable. In addition, fingerprinting and a heatmap were established to demonstrate the content trends of F. mandshurica more visually from different origins. Multivariate analysis, including principal component analysis and partial least squares discriminant analysis, was performed to determine the chemical characteristics of different parts of F. mandshurica, and six characteristic secoiridoids that could be used to distinguish different origins were screened. Finally, the inhibition of tyrosinase, α-glucosidase, acetylcholinesterase and pancreatic lipase activities by the nine characteristic compounds and extracts from different parts were investigated, and the results showed that they all exhibited different degrees of enzyme activity inhibition and thus have potential applications in whitening and blemish removal, hypoglycemia, anti-Alzheimer's disease and anti-obesity as a new source of natural enzyme activity inhibitors. This study establishes an identification and evaluation method applicable to phytochemistry of different origins, which is a guideline for quality control, origin evaluation and clinical application of traditional medicinal plants. This is also an unprecedented study on the identification of the chemical composition of different parts of F. mandshurica, characteristic compounds and the inhibition of enzyme activity of extracts from different parts.

Chemometrics-based Chemical Analysis of Myrrh and Its Vinegar-processed Products by UPLC-MS/MS

Myrrh is widely used in clinical practice but accompanied by obvious toxicity. According to traditional Chinese medicines theory, processing with vinegar can effectively reduce its toxicity. However, the detoxification processing technology of Myrrh and the corresponding mechanism have been unclear. The objective of this study is to systematically analyze the variation in chemical composition of raw Myrrh and its processed products using UPLC-Q-TOF-MS/MS coupled with chemometrics. A total of 75 compounds including 56 sesquiterpenoids, 2 diterpenoids, 15 triterpenoids and 2 other types were identified. Raw Myrrh and its processed products were divided into two major groups, and 14 chemical markers were selected out by principal component analysis and partial least square discriminant analysis. Additionally, the exact content of 5 representative chemical markers was determined to be significantly reduced after vinegar-processing by UPLC-QQQ-MS/MS. Moreover, multivariate statistical analysis and the quantitative results comprehensively indicated that the optimized processing method was processing at a ratio of 200 : 5 (Myrrh:vinegar). This research provides not only a reliable foundation for the study of Myrrh, but also a scientific reference for clinical use of this herb.

Relation between Strawberry Fruit Redness and Bioactivity: Deciphering the Role of Anthocyanins as Health Promoting Compounds

The red colour of most berries is often associated to fruit healthiness, since it has been linked to enrichment in anthocyanins (polyphenol with antioxidative properties). However, recent studies suggest that anthocyanins could not be the major contributors to bioactivity leading to uncertainty about their role as important molecules in the generation of health-promoting properties. To shed light on this issue, spectrophotometric and HPLC techniques were used for characterizing the content of phenolic compounds, including anthocyanins, in fruits of red (Fragaria x ananassa, cv. Fortuna) and white strawberry (Fragaria vesca spp. XXVIII) species (distinguishing receptacle from achene). In addition, the effect of these extracts on the reduction of intracellular ROS was tested, as well as on the activity of antioxidant enzymes and the quantification of cell oxidation markers. The results showed that white receptacle extracts (deprived of anthocyanins) were able to protect cells from oxidative damage to a greater extent than red fruits. This could be due per se to their high antioxidant capacity, greater than that shown in red fruits, or to the ability of antioxidants to modulate the activity of antioxidant enzymes, thus questioning the positive effect of anthocyanins on the wholesomeness of strawberry fruits. The results shed light on the relevance of anthocyanins in the prevention of health-associated oxidative damage.

Phenolic Composition of Brazilian BRS Carmem (Muscat Belly A × BRS Rúbea) Grapes: Evaluation of Their Potential Use as Bioingredients

The BRS Carmem grape was developed as an alternative for processing juices and wines. This study aimed to determine the phenolic compounds (PC) in the edible parts of this grape from two harvests-one harvested at ideal maturation time and another when the grapes were still immature-using HPLC-DAD-ESI-MS/MS. Student's t-test was used (α = 0.05) to evaluate differences in the PC content between the edible parts and between the harvests. Both skins showed a predominance of flavonols, anthocyanins, hydroxycinnamic acids derivatives (HCAD) and stilbenes, with higher concentrations for harvest 1 than harvest 2. For both harvests (harvest 1 and harvest 2), the HCAD (mg of caftaric acid•kg fruit^-1) was higher in whole grapes (383.98 and 67.09) than in their skins (173.95 and 21.74), with a predominance of trans-caffeic acid for all samples; the flavan-3-ols and proanthocyanidins (mg of (+)-catechin•kg fruit^-1) presented higher concentrations in the seeds (flavan-3-ols: 203.20 and 182.71, proanthocyanidins: 453.57 and 299.86) than in the skins (flavan-3-ols: 1.90 and 4.56, proanthocyanidins: 37.58 and 98.92); the stilbenes concentration (µg 3-glc-resveratrol•kg fruit^-1) was higher for the seeds from harvest 2 (896.25) than those from harvest 1 (48.67). BRS Carmem grapes contain a phenolic composition complex, and still have a relevant concentration of flavonols, anthocyanins and stilbenes, even when immature.

Unveiling the Potential of Polyphenols as Anti-Amyloid Molecules in Alzheimer's Disease

Alzheimer's disease (AD) is a devastating neurodegenerative disease that mostly affects the elderly population. Mechanisms underlying AD pathogenesis are yet to be fully revealed, but there are several hypotheses regarding AD. Even though free radicals and inflammation are likely to be linked with AD pathogenesis, still amyloid-beta (Aβ) cascade is the dominant hypothesis. According to the Aβ hypothesis, a progressive buildup of extracellular and intracellular Aβ aggregates has a significant contribution to the AD-linked neurodegeneration process. Since Aβ plays an important role in the etiology of AD, therefore Aβ-linked pathways are mainly targeted in order to develop potential AD therapies. Accumulation of Aβ plaques in the brains of AD individuals is an important hallmark of AD. These plaques are mainly composed of Aβ (a peptide of 39-42 amino acids) aggregates produced via the proteolytic cleavage of the amyloid precursor protein. Numerous studies have demonstrated that various polyphenols (PPHs), including cyanidins, anthocyanins, curcumin, catechins and their gallate esters were found to markedly suppress Aβ aggregation and prevent the formation of Aβ oligomers and toxicity, which is further suggesting that these PPHs might be regarded as effective therapeutic agents for the AD treatment. This review summarizes the roles of Aβ in AD pathogenesis, the Aβ aggregation pathway, types of PPHs, and distribution of PPHs in dietary sources. Furthermore, we have predominantly focused on the potential of food-derived PPHs as putative anti-amyloid drugs.

Comparative Study on Grape Berry Anthocyanins of Various Teinturier Varieties

The red-fleshed grape cultivars, called teinturier or dyer grapes, contain anthocyanins in both the skin and flesh. These phenolic compounds exhibit excellent coloring ability, and as antioxidants, they are important bioactive compounds in food crops. In this work, anthocyanin patterns of grape berries of fifteen teinturier varieties collected from the gene bank located at Pécs in the southwest of Hungary were compared. Anthocyanin profiles of numerous varieties originating from Hungary such as 'Bíborkadarka', 'Kármin', 'Kurucvér', and 'Turán' are reported for the first time. Anthocyanins extracted separately from the skin and juice were analyzed using high-performance liquid chromatography coupled with a photodiode array detector. For the identification of compounds, high-resolution orbitrap mass spectrometry was used. All in all, twenty-one anthocyanins were identified and quantified. We found that anthocyanin patterns differed significantly in the skin and juice for all investigated cultivars. For Vitis vinifera varieties, the predominant anthocyanin in the skin was malvidin-3-O-glucoside, while the main pigment in the juice was peonidin-3-O-glucoside. For the first time, a significant amount of diglucosides was detected in two Vitis Vinifera cultivars with a direct relationship. In general, the pigment composition of the skin was much more complex than that of the juice. The comparative study with presented patterns gives valuable and beneficial information from a chemotaxonomical point of view. Our results also help to choose the appropriate teinturier varieties with the desired anthocyanins for food coloring or winemaking purposes.

Effect of Aqueous Extract of Phenolic Compounds Obtained from Red Wine in Experimental Model of Colitis in Mice

Background: Inflammatory bowel disease (IBD) is a chronic relapsing inflammatory disorder represented by Crohn’s disease and ulcerative colitis. Currently, there is no cure and pharmacological treatment aims to induce and maintain remission on patients. Because the therapy reveals a relatively high toxicity, during a long-term utilization, it is essential to investigate new pharmacological approaches. Polyphenols, commonly present on red wine, have shown health-beneficial effects related to their antioxidant and anti-inflammatory effects through the inhibition of NF-kB activation, COX-2 and iNOS induction. In this sense, it would be interesting to study their effects in an IBD context. Therefore, this study aims to evaluate the effects of an aqueous extract of phenolic compounds in a 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced model of colitis. Method: Experimental colitis was induced in mice through an intrarectal administration of TNBS and then the mice were treated with an aqueous extract of phenolic compounds intraperitoneally for four days. Results and Discussion: The extract demonstrated an anti-inflammatory effect, reducing TNF-α levels in the colon, and had a beneficial effect on the extraintestinal manifestations related to IBD, without any significant side effects. The extract of phenolic compounds demonstrated to be a valuable object of study for the management of IBD in the future.

Anthocyanins: Traditional Uses, Structural and Functional Variations, Approaches to Increase Yields and Products' Quality, Hepatoprotection, Liver Longevity, and Commercial Products

Anthocyanins are water-soluble, colored compounds of the flavonoid class, abundantly found in the fruits, leaves, roots, and other parts of the plants. The fruit berries are prime sources and exhibit different colors. The anthocyanins utility as traditional medicament for liver protection and cure, and importance as strongest plants-based anti-oxidants have conferred these plants products different biological activities. These activities include anti-inflammation, liver protective, analgesic, and anti-cancers, which have provided the anthocyanins an immense commercial value, and has impelled their chemistry, biological activity, isolation, and quality investigations as prime focus. Methods in extraction and production of anthocyanin-based products have assumed vital economic importance. Different extraction techniques in aquatic solvents mixtures, eutectic solvents, and other chemically reactive extractions including low acid concentrations-based extractions have been developed. The prophylactic and curative therapy roles of the anthocyanins, together with no reported toxicity has offered much-needed impetus and economic benefits to these classes of compounds which are commercially available. Information retrieval from various search engines, including the PubMed®, ScienceDirect®, Scopus®, and Google Scholar®, were used in the review preparation. This imparted an outlook on the anthocyanins occurrence, roles in plants, isolation-extraction, structures, biosynthetic as well as semi- and total-synthetic pathways, product quality and yields enhancements, including uses as part of traditional medicines, and uses in liver disorders, prophylactic and therapeutic applications in liver protection and longevity, liver cancer and hepatocellular carcinoma. The review also highlights the integrated approach to yields maximizations to meet the regular demands of the anthocyanins products, also as part of the extract-rich preparations together with a listing of marketed products available for human consumption as nutraceuticals/food supplements.

Grape bioactive molecules, and the potential health benefits in reducing the risk of heart diseases

Grapes are a rich source of bioactive molecules including phenolic acids, flavonoids, anthocyanins, stilbenes, and lipids. These are the compounds which contribute to the health benefits of grape and grape-derived products. They possess antioxidant, antimicrobial, anti-inflammatory, and anti-carcinogenic activities and have wide applications in food and nutraceutical industries. Use of grape extracts rich in these bioactive compounds are linked to reduced incidence of cardiovascular disease and its major risk factors including hypertension (high blood pressure); a clinical condition associated with high mortality worldwide. Therefore, considerable attention has been given to grape-based products to alleviate and treat hypertension. The aim of this review is to summarize the bioactive compounds of grapes, composition changes in different grape extracts and the potential benefits in reducing hypertension.

Determination and Chemometrics-Assisted Comparative Analysis of Active Components in Different Tissue of Rana chensinensis

In this study, the chemical composition of different tissues of Rana temporaria chensinensis David derived from the same individual was analyzed by comparative approach. First, pre-column derivatization combined with high performance liquid chromatography (HPLC) was established to determine the content of 1-methyl hydantoin in samples, which used S1–S5 samples. The results indicated that 1-methyl hydantoin was determined in Oviductus Ranae (OR), Rana chensinensis ovum (RCO), Rana chensinensis meat (RCM), and Rana chensinensis skin (RCS), except for Rana chensinensis bone (RCB). Moreover, the content of it in RCS was the highest. In addition, the contents of six polyunsaturated fatty acids (PUFAs) in different tissues of Rana chensinensis were measured by HPLC, including eicosapentaenoic acid (EPA), α-linolenic acid (ALA), docosahexaenoic acid (DHA), arachidonic acid (ARA), linoleic acid (LA) and oleic acid (OA). The results indicated that OR, RCO, RCM, RCS, and RCB all contained the above six PUFAs. With the aid of chemometrics methods, the results of principal component analysis (PCA), hierarchical cluster analysis (HCA), and orthogonal partial least squares discriminant analysis (OPLS-DA) combined with the sequencing results of the total PUFAs content of each sample, showed that different tissues of Rana chensinensis could be divided into four categories, and the RCO sample was divided into one category because of the highest PUFAs content, which was a good source of PUFA. For comparison, OR and other tissue from the perspective of PUFAs, we also established OPLS-DA models of them. It could be found that the RCM was the most similar to the OR in the diversity and content of PUFAs. This study provided a theoretical basis for the further development and utilization of RCO, RCM, RCS, and RCB as by-products of OR.

Normal-phase chromatographic separation of pigmented wine tannin by nano-HPLC quadrupole time-of-flight tandem mass spectrometry and identification of candidate molecular features

BACKGROUND

As a wine ages, altered sensory properties lead to changes in perceived quality and value. Concurrent modifications of anthocyanin and tannin occur forming pigmented tannin, softening astringency and retaining persistent color. Wine tannin extracts of 1990 and 2010 vintages of Oakville Station Cabernet Sauvignon have been analyzed using normal-phase chromatography with tandem quadrupole time-of-flight mass spectrometry (QToF) to investigate the compositional differences in their pigmented tannin fractions.

RESULTS

The older wine demonstrates much greater structural diversity and a range of more polar compounds, while the younger wine contains fewer observed ion peaks. Several hundred molecular features are observable, and, as expected, there is progression to higher molecular weights after long aging. Between 7% and 16% of molecular features could be matched to a database of anticipated pigmented tannin compounds. Many signals had multiple possible isomeric identities, but fragmentation to resolve their identity was stymied by low sensitivity of the tandem mass spectrometric capability provided by QToF, so isomeric disambiguation is incomplete.

CONCLUSIONS

The chromatography displayed a high degree of resolution in aged wines, separating many of the known pigment types, including aldehyde bridged compounds, pyranoanthocyanins and direct condensation products among others, as well as resolving a great number of unknown compounds. Expanding our understanding of red wine pigments will lead to better wines as winemakers will be able to associate quality with particular wine pigment profiles once we can distinguish the relevant patterns in those pigments. © 2021 Society of Chemical Industry.

Salicylic acid and oxalic acid in enhancing the quality and extending the shelf life of grape cv. Thompson seedless

Postharvest life of table grapes is usually shortened by berry softening, berry drop, stem browning, fungal decay. Salicylic acid reduces fruit respiration and ethylene biosynthesis, during storage of fruits. Similarly, application of oxalic acid is a secure and hopeful postharvest handling technology for keeping quality and prolonging storage life of fruit. To study the effect of Salicylic acid and oxalic acid in enhancing the quality and extending the shelf life of grape, the present investigation was conducted. The grape berries were treated with Oxalic acid (OA) (1, 2, 3, 4, and 5 mM) and Salicylic acid (SA) (0.5, 1, 1.5 and 2 mM). The treatments were compared within 16th days at an interval of 4 days. Among the treatments, SA (2 mM) showed superiority in different quality attributing characters like physiological loss in weight (PLW), berry firmness, rachis browning, berry appearance, fungal decay, berry shattering, TSS, ascorbic acid, titratable acidity, total sugars, reducing sugars, TSS: acid ratio, taste, overall acceptability and shelf life. Hence, SA (2 mM) can be used as an effective strategy for maintaining quality of table grapes.

Characterization of Tempranillo negro (VN21), a high phenolic content grapevine Tempranillo clone, through UHPLC-QqQ-MS/MS polyphenol profiling

Grapevine cultivar and clone genotype is an important factor in the phenolic composition of wine. In this study, a new intense dark black berry color variant of Tempranillo, known as Tempranillo negro or VN21, is described. A targeted chromatographic approach based on UHPLC-QqQ-MS/MS was used to study the anthocyanins and non-colored phenols of the grape berry (skin and seeds) and wine. RJ43, one of the most cultivated clones in D.O.Ca. Rioja (Spain), was analyzed for comparison. Results suggest that the unique color of the grape skin in Tempranillo negro could be explained by higher concentrations of peonidin and cyanidin derivatives. This genotype accumulated anthocyanins in the seeds. Those differences in the berry were enhanced in the VN21 wines, which displayed notably higher concentrations of anthocyanins, and significantly increased contents of proanthocyanidins and stilbenes. This study exemplifies the application of phenol chromatographic analyses of spontaneous somatic variants to grapevine clonal selection.

Digital image-based tracing of geographic origin, winemaker, and grape type for red wine authentication

This work proposes the development of a simple, fast, and inexpensive methodology based on color histograms (obtained from digital images), and supervised pattern recognition techniques to classify red wines produced in the São Francisco Valley (SFV) region to trace geographic origin, winemaker, and grape variety. PCA-LDA coupled with HSI histograms correctly differentiated all of the SFV samples from the other geographic regions in the test set; SPA-LDA selecting just 10 variables in the Grayscale + HSI histogram achieved 100% accuracy in the test set when classifying three different SFV winemakers. Regarding the three grape varieties, SPA-LDA selected 15 variables in the RGB histogram to obtain the best result, misclassifying only 2 samples in the test set. Pairwise grape variety classification was also performed with only 1 misclassification. Besides following the principles of Green Chemistry, the proposed methodology is a suitable analytical tool; for tracing origins, grape type, and even (SFV) winemakers.

Anthocyanins Potentially Contribute to Defense against Alzheimer's Disease

Anthocyanins (ANTs) are plant pigments that belong to a flavanol class of polyphenols and have diverse pharmacological properties. These compounds are primarily found in fruits and vegetables, with an average daily intake of 180 mgd-1 of these compounds in the developed world. ANTs are potent antioxidants that might regulate the free radical-mediated generation of amyloid peptides (Abeta-amyloids) in the brain, which causes Alzheimer's disease (AD). This study presents a literature review of ANTs from different berries and their potential therapeutic value, with particular emphasis on neurodegenerative AD, which owing to oxidative stress. This review also highlights reactive oxygen species (ROS) generation through energy metabolism, nitrogen reactive species, the role of transition metals in generating ROS, and the radical-quenching mechanisms of natural antioxidants, including ANTs. The current status of the bioavailability, solubility, and structure activity relationship of ANTs is discussed herein.

Cysteine-Rich Peptide Fingerprinting as a General Method for Herbal Analysis to Differentiate Radix Astragali and Radix Hedysarum

Species misidentification and adulteration are major concerns in authenticating herbal medicines. Radix Astragali (RA), the roots of Astragalus membranaceus, is a traditional herbal medicine used for treating diabetes. However, it is often substituted by Radix Hedysarum (RH), the roots of Hedysarum polybotrys from the same plant family Fabaceae, which possesses different bioactivities. Current authentication methods, focusing on the chemical composition differences of herbal medicines based on small molecules, have limitations when these chemical markers are found in many species. Herein, we describe a rapid and general method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), coupled with multivariate analyses to differentiate herbal medicines. We used cysteine-rich peptide (CRP) fingerprinting, a method that exploits an underexplored chemical space between 2 to 6 kDa and which is populated by highly stable CRPs. To show the generality of the method, we screened 100 medicinal plant extracts and showed that CRP fingerprints are unique chemical markers. In addition, CRP fingerprinting was many-fold faster than the conventional authentication method using ultra-performance liquid chromatography (UPLC). Multivariate analyses showed that it has comparable classification accuracy as UPLC fingerprinting. Together, our findings revealed that CRP fingerprinting coupled with multivariate analyses is a rapid and general method for authentication and quality control for natural products in medicinal plants.

Chemical compositions and α-glucosidase inhibitory effects of anthocyanidins from blueberry, blackcurrant and blue honeysuckle fruits

The chemical compositions and α-glucosidase inhibitory activities of anthocyanins extracted from blueberry, blackcurrant and blue honeysuckle fruits and their acid hydrolysates (anthocyanidins) were analysed. Those anthocyanins were glycosidic anthocyanins that converted to anthocyanidins during acid hydrolysis, leading to increases in their α-glucosidase inhibitory activities (expressed as IC₅₀ values) from 0.232, 0.152 and 0.188 to 0.113 to 0.005 and 0.025 mg/mL. The potential inhibitory mechanism of these anthocyanidins was then investigated through inhibition kinetics, fluorescence quenching and docking simulations. The results showed the following: 1) all anthocyanidins were mixed-type inhibitors of α-glucosidase and they bind more tightly to free α-glucosidase as compared to the α-glucosidase-substrate complex; 2) anthocyanidin inhibition of α-glucosidase was a static procedure, presumably driven by hydrophobic associations and hydrogen bonding; and 3) all anthocyanidins were inserted into the active site of α-glucosidase and avoided the entrance of p-nitrophenyl-a-D-glucopyranoside. This study is valuable for anthocyanidins as potential α-glucosidase inhibitors.

Simultaneous determination of eight flavonoids in Sedum sarmentosum Bunge from different areas by UHPLC with triple quadrupole MS/MS

Sedum sarmentosum Bunge (SSB) is a traditional Chinese herbal medicine containing multiple components that has been extensively used clinically to treat chronic viral hepatitis and some inflammatory diseases. Total flavonoids are major pharmacologically active components of SSB. To gain a deeper understanding of SSB resources, we analyzed eight chemical constituents in 33 batches of SSB from 11 regions in China. An accurate, precise and sensitive ultra-high-performance liquid chromatography coupled with triple quadrupole electrospray tandem mass spectrometry method was developed for the determination of eight flavonoids in SSB. Under the optimized chromatographic conditions, good separation for the eight target components was obtained on an Agilent Zobax SB C₁₈ (50 × 2.1 mm, 5 μm) column within 4 min. The established methods were validated with good linearity (r ≥ 0.9988), precision (RSD ≤ 2.68%), stability (1.43-3.28%) and repeatability (1.14-2.89%). Moreover, the average recoveries were 95.91-100.68%, and the RSDs were 1.50-3.80%. In addition, the analytical conditions of UPLC-ESI-MS/MS provided better sensitivity with a shorter analysis time when compared with the HPLC-DAD method. Hierarchical clustering analysis and principal component analysis were performed to estimate and classify these samples based on the contents of the eight chemical constituents. This study provided the theoretical basis and scientific evidence for the development and utilization of SSB resources.

Protein-Based Fingerprint Analysis for the Identification of Ranae Oviductus Using RP-HPLC

This work demonstrated a method combining reversed-phase high-performance liquid chromatography (RP-HPLC) with chemometrics analysis to identify the authenticity of Ranae Oviductus. The fingerprint chromatograms of the Ranae Oviductus protein were established through an Agilent Zorbax 300SB-C8 column and diode array detection at 215 nm, using 0.085% TFA (v/v) in acetonitrile (A) and 0.1% TFA in ultrapure water (B) as mobile phase. The similarity was in the range of 0.779-0.980. The fingerprint chromatogram of Ranae Oviductus showed a significant difference with counterfeit products. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) successfully identified Ranae Oviductus from the samples. These results indicated that the method established in this work was reliable.

Combinatorial approach for improved cyanidin 3-O-glucoside production in Escherichia coli

BACKGROUND

Multi-monocistronic and multi-variate vectors were designed, built, and tested for the improved production of cyanidin 3-O-glucoside (C3G) in Escherichia coli BL21 (DE3). The synthetic bio-parts were designed in such a way that multiple genes can be assembled using the bio-brick system, and expressed under different promoters in a single vector. The vectors harbor compatible cloning sites, so that the genes can be shuffled from one vector to another in a single step, and assembled into a single vector. The two required genes: anthocyanidin synthase (PhANS) from Petunia hybrida, and cyanidin 3-O-glucosyltransferase (At3GT) from Arabidopsis thaliana, were individually cloned under PT7, Ptrc, and PlacUV5 promoters. Both PhANS and At3GT were shuffled back and forth, so as to generate a combinatorial system for C3G production. The constructed systems were further coupled with the genes for UDP-D-glucose synthesis, all cloned in a multi-monocistronic fashion under PT7. Finally, the production of C3G was checked and confirmed using the modified M9 media, and analyzed through various chromatography and spectrometric analyses.

RESULTS

The engineered strains endowed with newly generated vectors and the genes for C3G biosynthesis and UDP-D-glucose synthesis were fed with 2 mM (+)-catechin and D-glucose for the production of cyanidin, and its subsequent conversion to C3G. One of the engineered strains harboring At3GT and PhANS under Ptrc promoter and UDP-D-glucose biosynthesis genes under PT7 promoter led to the production of ~ 439 mg/L of C3G within 36 h of incubation, when the system was exogenously fed with 5% (w/v) D-glucose. This system did not require exogenous supplementation of UDP-D-glucose.

CONCLUSION

A synthetic vector system using different promoters has been developed and used for the synthesis of C3G in E. coli BL21 (DE3) by directing the metabolic flux towards the UDP-D-glucose. This system has the potential of generating better strains for the synthesis of valuable natural products.

Comparison and multivariate statistical analysis of anthocyanin composition in Lycium ruthenicum Murray from different regions to trace geographical origins: The case of China

Anthocyanin composition in forty-five Lycium ruthenicum Murray (LRM) samples grown in China was identified by high-performance liquid chromatography-electrospray ionisation-mass spectrometry (HPLC-ESI-MS) and quantified by HPLC with a diode array detector (HPLC-DAD). The results showed that the overall pattern of anthocyanin composition of LRM from different provinces was the same, while the individual and total anthocyanin concentrations, were significantly different, indicating an important impact of geographical origin on anthocyanin composition, which can be considered as credible indices for LRM classification. Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to develop discrimination models for the anthocyanin concentrations. PCA clearly separated the LRM based on its geographical origins. LDA satisfactorily categorized the samples by providing a 100% success rate based on geographical origins. The results obtained could be used to trace the geographical origin of LRM.

Characterisation of (poly)phenolic constituents of two interspecific red hybrids of Rondo and Regent (Vitis vinifera) by LC-PDA-ESI-MS QTof

The aim of this study was to identify and compare phenolic acids, flavan-3-ols, flavonols, and anthocyanins in two the most popular interspecific hybrids of red grapes, Rondo and Regent, nowadays very popular in red wine production in Poland. The phenolic profiles of these hybrids have not yet been reported. Thirty-three phenolic compounds, including 2 flavan-3-ols, 3 phenolic acids, 5 flavonols, and 23 anthocyanins, were determined in the examined samples using the ultra-performance liquid chromatography photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS) method. Major differences were found in the phenolic profiles of investigated cultivars. The Regent hybrid exhibited the highest total phenolics content (27029.75mg/kg dry matter) but Rondo was characterized by the highest concentration of anthocyanins (19342.36mg/kgdm). The dominant fraction was anthocyanin compounds, especially acetylated>diglucosylated forms than glucosylated ones. This data represents valuable information that may be useful for oenological practices and to valorise these varieties as sources of bioactive compounds.

Optimisation of pulsed electric fields extraction of anthocyanin from Beibinghong Vitis Amurensis Rupr

Beibinghong Vitis amurensis Rupr has wide plantation area, high productivity and rich anthocyanin. Common hot-extraction has poor deficiency and destroys anthocyanin severely. For Beibinghong V. amurensis Rupr as materials, response surface-optimised electric fields were used, the structure of Beibinghong was observed by SEM, antioxidant activity was measured by DPPH, ABTS and reducing force, the component of anthocyanin was analyzed by HPLC-MS. We found the content of total anthocyanin extracted by pulsed electric fields was 166.65 ± 3.88 mg/100 g.FW. Total anthocyanin from Beibinghong had high antioxidant activity, also contained multiple steady anthocyanin of delphinidin 3-O-glucoside, cyanidin 3-O-glucoside, petunidin 3-O-glucoside, peonidin 3-O-glucoside, malvidin 3-O-glucoside, delphinidin-3-O-(6-O-acetyl) glucoside and delphinidin-3-O-(6-O-p-coumaroyl) glucoside et al. In conclusion, the optimised pulsed electric fields method can quickly and efficiently extract several kinds of anthocyanins from V. amurensis Rupr. This study promoted the intensive processing of V. amurensis Rupr and widened the practical application of pulsed electric field technology.

Spontaneous variation regarding grape berry skin color: A comprehensive study of berry development by means of biochemical and molecular markers

Understanding grape berry development and the metabolism of different classes of compounds responsible for traits like berry's color is imperative to control and improve quality aspects of grapes. A colorimetric, biochemical and molecular characterization allowed the comprehensive description of the pigment-related characteristics of nine berry skin color somatic variants, belonging to four different varieties. Although the observed berry skin color variability was not fully explained by MybA locus, the phenolic profiles allowed inferring about specific interferences among the biosynthetic pathways. Data were consistent concerning that grapes showing cyanidin-3-O-glucoside as the major anthocyanin and flavonols with two substituent groups in the lateral B-ring are generally originated by a white ancestor. After retro-mutation, these grapes seem to keep the dysfunction on flavonoid hydroxylases enzymes, which negatively affect the synthesis of both flavonols and anthocyanins with three substituent groups in the lateral B-ring. Overall, the obtained results indicate that the color differences observed between somatic variants are not solely the result of the total amount of compounds synthesized, but rather reflect a different dynamics of the phenolic pathway among the different color variants of the same variety.

CHEMICAL COMPOUNDS

Gallic acid (PubChem CID: 370); Caftaric acid (PubChem CID: 6,440,397); Catechin (PubChem CID: 73,160); Epigallocatechin gallate (PubChem CID: 65,064); Quercetin-3-O-galactoside (PubChem CID: 5,281,643); Quercetin-3-O-glucoside (PubChem CID: 25,203,368); Malvidin-3-O-glucoside (PubChem CID: 443,652); Peonidin-3-O-p-coumaroylglucoside (PubChem CID: 44,256,849); Malvidin-3-O-p-coumaroylglucoside (PubChem CID: 44,256,988); Resveratrol-3-O-glucoside (PubChem CID: 25,579,167).

Anti-oxidant, anti-inflammatory, analgesic and antipyretic activities of grapevine leaf extract (Vitis vinifera) in mice and identification of its active constituents by LC-MS/MS analyses

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Vitis vinifera is used in traditional medicine for diarrhea, hepatitis and stomachaches. The objective of this study was to investigate the anti-oxidant, anti-inflammatory, analgesic and antipyretic properties of the hydroalcoholic leaf extract of Vitis vinifera (EVV) on experimental models to provide scientific basis for its use.

MATERIALS AND METHODS

The EVV was chemically characterized by LC-MS/MS analyses. The in vitro antioxidant activities of the EVV extract were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and Ferric reducing antioxidant power assay (FRAP). Analgesic activity using acetic acid induced writhing and formalin test in mice, anti-inflammatory activity using carrageenan induced paw oedema and acetic acid-induced vascular permeability in mice, and antipyretic activity using Brewer's yeast induced pyrexia in rats were evaluated at 100mg/kg, 200mg/kg, and 400mg/kg doses of the extract.

RESULTS

The extract (EVV) was found to contain resveratrol, quercetin, catechin, flavone, flavonols, anthocyanin, gallic acid and epicatechin. EVV produced significant dose-response anti-inflammatory activity against carrageenan-induced paw edema. EVV at dosages of 100, 200 and 400mg/kgbw significantly reduced carrageenan-induced paw edema by 34.48% (P<0.05), 36.20% (P<0.05), and 41.37% (P<0.05) at 5h after carrageenan injection, respectively. Also EVV extract reduces significantly acetic acid-induced vascular permeability in mice dose dependently. EVV (100, 200 and 400mg/kgbw) produced significant dose-response analgesic activity in the formalin test. However, the low percentage inhibition (50%) suggests that it is not a centrally acting analgesic. Extract at dosages of 100, 200 and 400mg/kg bw, p.o. significantly reduced acetic acid-induced writhing by 48.15% (p<0.05), 57.97% (p<0.05), and 68.09% (p<0.05), respectively. The extract also caused marked dose-dependent inhibition of formalin-induced pain in the second phase (p<0.05). Statistical significant reduction in rectal temperatures was observed in standard group at 21 and 23h, and in 200mg/kg and 400mg/kg doses of the extract at 23h (p<0.05) compared with the 19h.

CONCLUSIONS

The results obtained indicated potential analgesic, anti-inflammatory and antipyretic effects of them hydroalcoholic leaf extract of V. vinifera observed at doses tested which support the claim for the traditional use of the plant in the treatment of various inflammatory and pain diseases.

Use of Visible and Short-Wave Near-Infrared Hyperspectral Imaging To Fingerprint Anthocyanins in Intact Grape Berries

In red grape berries, anthocyanins account for about 50% of the skin phenols and are responsible for the final wine color. Individual anthocyanin levels and compositional profiles vary with cultivar, maturity, season, region, and yield and have been proposed as chemical markers to differentiate wines and to provide valuable information regarding the adulteration of musts and wines. A fast, easy, solvent-free, nondestructive method based on visible, short-wave, and near-infrared hyperspectral imaging (HSI) in intact grape berries to fingerprint the color pigments in eight different grape varieties was developed and tested against HPLC. Predictive models based on modified partial least-squares (MPLS) were built for 14 individual anthocyanins with coefficients of determination of cross-validation (R²_CV) ranging from 0.70 to 0.93. For the grouping of total and nonacylated anthocyanins, external validation was conducted with coefficient of determination of prediction (R²_P) of 0.86. HSI could potentially become an alternative to HPLC with reduced analysis time and labor costs while providing reliable and robust information on the anthocyanin composition of grape berries.

Quality Evaluation of Traditional Chinese Medicine Compounds in Xiaoyan Lidan Tablets: Fingerprint and Quantitative Analysis Using UPLC-MS

XiaoyanLidan tablets (XYLDTs) are traditional Chinese medicines frequently used for syndromes of the liver and gallbladder, cholecystitis and cholangitis. To evaluate the consistency of the quality of commercial XYLDT preparations, we established a simple and reliable ultra-performance liquid chromatography (UPLC) method with a photodiode array (PDA) detector and mass spectrometry (MS), including a fingerprint analysis and quantification of the main pharmacologically-active markers. In the UPLC-PDA detection-based fingerprint analysis of XYLDTs, approximately 39 peaks were found in the XYLDT chromatogram, 26 of which were attributed to Picrasmaquassioides, nine to Andrographis and four to Isodonserra. Subsequently, the structures of these bioactive markers were identified through ESI-MS analyses. Using the chemometricmethods of similarity analysis and principal component analysis, the five significant herbal componentswere determined as 4-methoxy-5-hydroxycanthin-6-one, andrographolide, dehydroandrographolide, neoandrographolide and rosmarinic acid, and these components were qualitatively assessed. Our experimental results demonstrated that combining the fingerprint analysis with UPLC-MS and multi-ingredient determination is useful for rapid pharmaceutical quality evaluation. Moreover, the combined approach can potentially differentiate the origin, determine the authenticity and assess the overall quality of the formulae.