Identification and quantification of phenolic compounds in diverse cultivars of eggplant grown in different seasons by high-performance liquid chromatography coupled to diode array detector and electrospray-quadrupole-time of flight-mass spectrometry

Influence of Harvest Time on the Chemical Profile of Pereskia aculeate Mill. Using Paper Spray Mass Spectrometry

This study evaluated the physicochemical characteristics and the production of bioactive compounds of Pereskia aculeata Mill. at different harvest times. Here, we performed a qualitative evaluation of the chemical profile by paper spray mass spectrometry (PSMS), the phenolic acid and flavonoid profile by high-performance liquid chromatography (HPLC), antioxidant activity, total carotenoids, total phenolic compounds, total flavonoids, total anthocyanins, color characteristics, total soluble solids (TSS), total solids (TS), pH, and total titratable acidity (TTA). The chemical profile was not affected, with the exception of 4,5-dimethyl-2,6-octadiene and azelaic acid, which was only identified in the leaves harvested during the winter. The content of four phenolic acids and three flavonoids were analyzed; out of these, no significant amounts of ellagic acid and quercetin were detected. There was no difference in production of bioactive compounds between seasons, reflecting the antioxidant activity, which also did not differ. Brightness, chroma, and leaf pH were the only physicochemical characteristics that did not vary between seasons.

Impact of the Cooking Process on Metabolite Profiling of Acanthocereus tetragonus, a Plant Traditionally Consumed in Mexico

Acanthocereus tetragonus (L.) Hummelinck is used as an alternative food source in some Mexican communities. It has been shown that the young stems of A. tetragonus provide crude protein, fiber, and essential minerals for humans. In this work, we analyzed the phytochemical profile, the total phenolic content (TPC), and the antioxidant activity of cooked and crude samples of A. tetragonus to assess its functional metabolite contribution to humans. The phytochemical profile was analyzed using Ultra-High-Performance Liquid Chromatography coupled to High-Resolution Mass Spectrometry (UHPLC-PDA-HESI-Orbitrap-MS/MS). Under the proposed conditions, 35 metabolites were separated and tentatively identified. Of the separated metabolites, 16 occurred exclusively in cooked samples, 6 in crude samples, and 9 in both crude and cooked samples. Among the detected compounds, carboxylic acids, such as threonic, citric, and malic acids, phenolic acids, and glycosylated flavonoids (luteolin-O-rutinoside) were detected. The TPC and antioxidant activity were analyzed using the Folin–Ciocalteu method and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical inhibition method, respectively. The TPC and antioxidant activity were significantly reduced in the cooked samples. We found that some metabolites remained intact after the cooking process, suggesting that A. tetragonus represents a source of functional metabolites for people who consume this plant species.

Genetic Diversity and Utilization of Cultivated Eggplant Germplasm in Varietal Improvement

Eggplant is the fifth economically most important vegetable in the Solanaceae family after tomato, potato, chili, and tobacco. Apart from the well-cultivated brinjal or aubergine eggplant (Solanum melongena L.), two other underutilized eggplant species, the African eggplant (S. macrocarpon L.) and the scarlet eggplant (S. aethiopicum L.), were also cultivated with local importance where the leaves and fruits are used for food and medicinal purposes. The major objectives of the eggplant breeding program are to improve fruit quality, increase yield performance through heterosis breeding, and introduce pest and disease resistances from wild relatives. Europe and Asia hold a wide collection of germplasm resources with significant potential for genetic improvement. While cultivated eggplant is susceptible to several fungi and bacteria, many wild relatives offer potential resistance to these pathogens. In this paper, we review the genetic resources and diversity of cultivated eggplant and its wild relatives. As a point of departure, we examine the economic importance, domestication, taxonomy characterization, and relationships of the crop and its wild relatives. The importance of evaluating and safeguarding wild relatives is highlighted, as crop wild relatives are highly underrepresented. A key section in this study is an overview dedicated to genetic resources, resistance to biotic and abiotic stresses, pre-breeding, and breeding for sustainable eggplant production.

Fruit composition profile of pepper, tomato and eggplant varieties grown under uniform conditions

The study of the diversity within and between major Solanaceae crops (pepper, tomato, eggplant) is of interest for the selection and development of balanced diets. We have measured thirty-six major fruit composition traits, encompassing sugars, organic acids, antioxidants and minerals, in a set of 10 accessions per crop for pepper, tomato and eggplant, grown under the same cultivation conditions. The aim was to evaluate the diversity within species and to provide an accurate comparison of fruit composition among species by reducing to a minimum the environmental effect. Pepper, tomato and eggplant had a clearly distinct composition profile. Pepper showed the highest average content in total sugars and organic acids. Fructose and glucose were the major sugar compounds in the three species, although in pepper and tomato sucrose was present only in trace amounts. Citric acid was the major organic acid in pepper and tomato, while in eggplant it was malic acid. Pepper and eggplant had the highest total antioxidant activity. Vitamin C content was much higher in pepper than in tomato and eggplant, while eggplant accumulated high concentrations of chlorogenic acid. Furthermore, eggplant was the species with higher content in most minerals, particularly for K, Mg and Cu, while pepper was the richest in Fe. Due to their complementary nutritional profiles, a combined regular consumption of the three vegetables would supply more than 20% of the Dietary Reference Intake of several of the analysed phytochemicals. The large diversity within each species is of interest for selecting varieties with better nutritional and organoleptic profiles, as well as for breeding new cultivars.

Eggplant Fruit (Solanum melongena L.) and Bio-Residues as a Source of Nutrients, Bioactive Compounds, and Food Colorants, Using Innovative Food Technologies

Consumers are very concerned with following a healthy diet, along with some precautions that may influence environmental impact. Solanum melongena L. is one of the most consumed vegetables due to its excellent nutritional value and antioxidant action. Associated with its high consumption, considerable amounts of agro-food wastes are produced. This work targets the valorization of this matrix, through the use of its bio-residues to study the obtention of coloring pigments, applying innovative technologies. Its nutritional value, chemical composition, and bioactive potential were evaluated, and the ultrasound-assisted extraction to obtain coloring pigments of high industrial interest was optimized. Considering the results, low contents of fat and carbohydrates and energy value were evident, as well as the presence of compounds of interest (free sugars, organic acids, unsaturated fatty acids, and phenolic acids). In addition, the antioxidant and antimicrobial potential was detected. Response surface methodology was performed to optimize the extraction of natural pigments, showing a concentration of 11.9 mg/g of anthocyanins/g of extract, applying optimal conditions of time, solvent, and solid/liquid ratio of 0.5 min, 68.2% (v/v) and 5 g/L, respectively. S. melongena proved to be a good source of bioactive compounds and natural pigments, which can generate great interest in the food industry.

Vegetable Soups and Creams: Raw Materials, Processing, Health Benefits, and Innovation Trends

Vegetable soups and creams have gained popularity among consumers worldwide due to the wide variety of raw materials (vegetable fruits, tubers, bulbs, leafy vegetables, and legumes) that can be used in their formulation which has been recognized as a healthy source of nutrients (mainly proteins, dietary fiber, other carbohydrates, vitamins, and minerals) and bioactive compounds that could help maintain the body’s health and wellbeing. In addition, they are cheap and easy to preserve and prepare at home, ready to eat, so in consequence they are very useful in the modern life rhythms that modify the habits of current consumption and that reclaim foods elaborated with natural ingredients, ecologic, vegans, less invasive production processes, agroindustry coproducts valorization, and exploring new flavors and textures. This review focuses on the nutritional and healthy properties of vegetable soups and creams (depending on the raw materials used in their production) highlighting their content in bioactive compounds and their antioxidant properties. Apart from the effect that some processing steps could have on these compounds, innovation trends for the development of healthier soups and creams adapted to specific consumer requirements have also been explored.

Degradation Kinetics of Anthocyanins from Purple Eggplant in a Fortified Food Model System during Microwave and Frying Treatments

A model food system was designed with dietary fiber and crude anthocyanins from purple eggplant peel to explore the degradation mechanism of anthocyanins during microwave and frying treatments. Our results found that delphinidin-3-O-rutinoside was either hydrolyzed into delphinidin or condensed with p-coumaric acid to form p-coumaroyl-delphinidin-3-O-glucoside. Delphinidin was cleaved into gallic acid and phloroglucinaldehyde, which might be further oxidized into pyrogallol and phloroglucinol, respectively. The total anthocyanin degradation followed the first-order kinetics in fried and microwaved solid matrix samples as well as microwaved liquid matrix samples. However, the total anthocyanin degradation followed the second-order kinetics in the heated liquid matrix samples at the frying temperature. The brown/polymeric color index, which negatively correlated with the anthocyanin content, increased faster in the liquid matrix samples than in the solid matrix samples. Compared with frying treatment, a higher rate of anthocyanin degradation in solution was observed under microwave treatment. However, anthocyanins were subject to much more damage under frying treatment than microwave treatment in a solid food system.

Anthocyanins, Vibrant Color Pigments, and Their Role in Skin Cancer Prevention

Until today, numerous studies evaluated the topic of anthocyanins and various types of cancer, regarding the anthocyanins' preventative and inhibitory effects, underlying molecular mechanisms, and such. However, there is no targeted review available regarding the anticarcinogenic effects of dietary anthocyanins on skin cancers. If diagnosed at the early stages, the survival rate of skin cancer is quite high. Nevertheless, the metastatic form has a short prognosis. In fact, the incidence of melanoma skin cancer, the type with high mortality, has increased exponentially over the last 30 years, causing the majority of skin cancer deaths. Malignant melanoma is considered a highly destructive type of skin cancer due to its particular capacity to grow and spread faster than any other type of cancers. Plants, in general, have been used in disease treatment for a long time, and medicinal plants are commonly a part of anticancer drugs on the market. Accordingly, this work primarily aims to emphasize the most recent improvements on the anticarcinogenic effects of anthocyanins from different plant sources, with an in-depth emphasis on melanoma skin cancer. We also briefly summarized the anthocyanin chemistry, their rich dietary sources in flowers, fruits, and vegetables, as well as their associated potential health benefits. Additionally, the importance of anthocyanins in topical applications such as their use in cosmetics is also given.

Effects of Infrared Radiation on Eggplant (Solanum melongena L.) Greenhouse Cultivation and Fruits' Phenolic Profile

The implementation of Infrared (IR) radiation in heated greenhouses possesses the advantage of high directional control and focused compensation of energy losses, appropriate for creating local microclimate conditions in highly energy-consuming systems, such as greenhouses. Moreover, it can efficiently maintain favorable environmental conditions at the plant canopy. The present study studies the application of Infrared (IR) heating in an experimental greenhouse with eggplant (Solanum melongena L.) cultivation. The experimental results are presented from a full cultivation period inside two identical, small scale experimental greenhouses, with IR and forced air heating system, respectively. The effects of IR heating over plant growth parameters, including the yield of the fruits as well as the total phenolic content and the antioxidant profile of eggplants fruits’ extracts are measured and discussed. The results indicate a greater uniformity production in the IR heating greenhouse in terms of antioxidant and radical scavenging activities, as well as the total phenolic content. Moreover, the phenolic profile of eggplant fruits from both greenhouses revealed the existence of numerous bioactive compounds, some of which were only characteristic of the eggplant fruits from IR heated greenhouses.

Monitoring of Chlorogenic Acid and Antioxidant Capacity of Solanum melongena L. (Eggplant) under Different Heat and Storage Treatments

Solanum melongena L., also known as eggplant, is a widely consumed vegetable and it is well-known for its beneficial antioxidant properties, due to phenolic compounds. In this work, the influence of different cooking procedures on the content of chlorogenic acid was evaluated on eggplant samples of different geographic origin by high-performance liquid chromatography (HPLC). An easy and quick extraction procedure with 50% methanol as the extraction solvent was optimized for the first time by means of a design-of-experiment and applied to heat treated samples of eggplant. The antioxidant capacity of eggplant extracts was also evaluated by using the ABTS assay and it was correlated with the data obtained by the HPLC method. The content of chlorogenic acid was different in each heat-treated eggplant sample and it depended on the temperature applied during the cooking procedure. In particular, an increase of chlorogenic acid content with rising temperature was observed. Conversely, a very high temperature (250 °C) caused a decrease of chlorogenic acid amount. The influence of storage on the content of chlorogenic acid was also monitored. While the level of chlorogenic acid in fresh samples decreased during four weeks of storage, an increase in its content in heat treated eggplant was observed within the same period. Multivariate data analysis was used to classify eggplant samples into different groups, according to the country of origin and heat treatment procedure. This study provides new insights to preserve the antioxidant properties of eggplant phenolics during different thermal and storage treatments in order to highlight their health promoting effects.

Phytochemical Characterization of Five Edible Purple-Reddish Vegetables: Anthocyanins, Flavonoids, and Phenolic Acid Derivatives

Vegetables comprise a significant portion of our daily diet with their high content in nutrients including fiber, vitamins, minerals, as well as phenolic compounds. Vegetable consumption has been shown to be positively associated with the prevention of several degenerative diseases thanks to their bioactive compounds. Accordingly, five selected vegetables, namely, red chicory, red onion, eggplant, purple sweet potato, and black carrot were thoroughly assessed for their phenolic content in this study. For this purpose, the total phenolic and flavonoid content of these five vegetables and their antioxidant activities that are based on three common methods ABTS radical cation decolorization assay (ABTS), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and DPPH scavenging activity assay were determined. Additionally, HPLC-PDA/Electrospray ionization coupled with mass spectrometry (HPLC-PDA/-ESI⁺-MS)-based identification and quantification of the members belonging to polyphenols present in each vegetable were determined. Statistical correlations between antioxidant activities and the specific type of phenolic compounds, such as anthocyanins, flavonoids, anthocyanins, and phenolic acids were further elucidated. Phenolic acids (chlorogenic and syringic acids) were found to be the most abundant compounds that are present in all samples. Among the anthocyanins, cyaniding derivatives were present in all vegetables. In terms of their antioxidant activities, the analyzed vegetables were ranked as red chicory > purple sweet potato > black carrot > eggplant > red onion, in descending order. Superior antioxidant activities exhibited by red chicory and purple sweet potato were attributed to the high content of phenolic compounds, especially flavonols (quercetin-3,4-O-diglucoside) in red chicory and anthocyanins (peonidin-3-caffeoyl p-hydroxybenzoylsophoroside-5-glucoside) in purple sweet potato.

Eggplant fruits protect against DNA damage and mutations

Eggplant belongs to the Solanaceae family, and it has an important antioxidant capability that has been shown to counteract oxidation, which is harmful to health and many diseases. In this present study, we evaluated the antigenotoxic effects of six eggplants ((Solanum aculeatissimum Jacq. 'Ma-khuea-lueang'; ML), (Solanum aculeatissimum Jacq. 'Ma-khuea-pro'; MP), (Solanum aculeatissimum Jacq. 'Ma-khuea-sawoei'; MS), (Solanum melongena Linn. 'Ma-khuea-khai-tao'; MKT), (Solanum melongena Linn. 'Ma-khuea-muang klom'; MM) and (Solanum torvum Sw. 'Ma-khuea-phuang'; MPH)) against urethane-induced somatic mutation and recombination test (SMART) in Drosophila melanogaster and hydrogen peroxide-induced oxidative DNA damage in human lymphocytes. First, we determined all of the eggplant extracts of their antioxidant properties including radical scavenging activities, reducing antioxidant power and total phenolic contents, surprisingly ML extract showed the highest level of activity. In SMART, larvae were fed with each lyophilized eggplant. The results revealed that no sample was mutagenic. Interestingly, we found that all six eggplants had a potent inhibitory effect against urethane-induced mutagenicity. Moreover, the protective effect of each eggplant extract against oxidative DNA damage in human lymphocytes was investigated using the single-cell gel electrophoresis (comet) assay. The treatment cells with six eggplant extracts prevented DNA human lymphocytes in response to hydrogen peroxide, especially ML extract exhibited higher an inhibition percentage than other samples. This study demonstrated that these eggplants seem to be safe for consumption and their extracts could protect against DNA damage. Thus, these eggplants have the potential to provide health benefits associated with prevention or reduced risk of developing chronic diseases, such as cancer.

A Polyphenol Rich Extract from Solanum melongena L. DR2 Peel Exhibits Antioxidant Properties and Anti-Herpes Simplex Virus Type 1 Activity In Vitro

DR2B and DR2C extracts, obtained by ethanolic maceration of peel from commercially and physiologically ripe aubergine berries, were studied for the antioxidative cytoprotective properties and anti-HSV-1 activity, in line with the evidence that several antioxidants can impair viral replication by maintaining reducing conditions in host cells. The antioxidative cytoprotective effects against tBOOH-induced damage were assessed in Caco2 cells, while antiviral activity was studied in Vero cells; polyphenolic fingerprints were characterized by integrated phytochemical methods. Results highlighted different compositions of the extracts, with chlorogenic acid and delphinidin-3-rutinoside as the major constituents; other peculiar phytochemicals were also identified. Both samples reduced reactive oxygen species (ROS) production and exhibited scavenging and chelating properties. DR2C partly counteracted the tBOOH-induced cytotoxicity, with a remarkable lowering of lactate metabolism under both normoxia and hypoxia; interestingly, it increased intracellular GSH levels. Furthermore, DR2C inhibited the HSV-1 replication when added for 24 h after viral adsorption, as also confirmed by the reduction of many viral proteins' expression. Since DR2C was able to reduce NOX4 expression during HSV-1 infection, its antiviral activity may be correlated to its antioxidant properties. Although further studies are needed to better characterize DR2C activity, the results suggest this extract as a promising new anti-HSV-1 agent.

Effect of Long-Term Xanthophyll and Anthocyanin Supplementation on Lutein and Zeaxanthin Serum Concentrations and Macular Pigment Optical Density in Postmenopausal Women

Xanthophylls (lutein, L; zeaxanthin, Z) and anthocyanins are often included in food supplements to improve ocular health. There are no dietary reference intakes for them. The aim was to assess the effects of L, Z and anthocyanin supplementation on short and long-term lutein status markers (serum concentration and macular pigment optical density (MPOD)). Seventy-two postmenopausal women were randomized into a parallel study of 8 months: Group A-anthocyanines (60 mg/day); Group X-xanthophylls (6 mg L + 2 mg Z/day); Group X+A-anthocyanines (60 mg/day) + xanthophylls (6 mg L + 2 mg Z/day). At the beginning of the study, 4 and 8 month serum L and Z concentrations were determined (HPLC), as well as L, Z and anthocyanine dietary intake and MPOD (heterochromic flicker photometry). Baseline concentrations of L (0.35 ± 0.19 μmol/L), Z (0.11 ± 0.05 μmol/L), L+Z/cholesterol/triglycerides (0.07 ± 0.04 μmol/mmol) increased in Group X (2.8- and 1.6-fold in L and Z concentrations) and in group XA (2- and 1.4-fold in L and Z concentrations). MPOD (baseline: 0.32 ± 0.13 du) was not modified in any of the groups at the end of the study. There were no differences in the dietary intake of L+Z and anthocyanin at any point in time in any group. Supplementation of L and Z at a dietary level provoked an increase in their serum concentration that was not modified by simultaneous supplementation with anthocyanins.

Comprehensive metabolite profiling of Solanum tuberosum L. (potato) leaves by HPLC-ESI-QTOF-MS

The objective of this work was to study the non-targeted metabolite profiling of potato leaves using high performance liquid chromatography coupled to quadrupole-time of flight mass spectrometry (HPLC-ESI-QTOF-MS). The mass accuracy, true isotopic pattern in both MS and MS/MS spectra provided by QTOF-MS made possible the tentative identification of 109 compounds present in potato leaves, including organic acids, amino acids and derivatives, phenolic acids, flavonoids, iridoids, oxylipins and other polar and semi-polar compounds. Among them, 32 compounds have been found for the first time in potato leaf and in the Solanaceae family. Quinic acid and its derivatives represented more than 45% of the bioactive compounds quantified in the extract. Derivatives of hydroxybenzoic acid and gentisic acid were also founded at considerable concentrations. This study shed light on the composition of potato leaf extract and will serve as a base for further research into activities of the various compounds found in this matrix which has demonstrated a potential use as functional ingredients.

Screening of Combinatorial Quality Markers for Natural Products by Metabolomics Coupled With Chemometrics. A Case Study on Pollen Typhae

Natural products, especially for traditional Chinese medicines (TCMs), are of great importance to cure diseases. Yet it was hard to screen the influential quality markers for monitoring the quality. A simple and comprehensive strategy was developed and validated to screen for the combinatorial quality markers for precise quality evaluation and discrimination of natural products. In this study, Pollen Typhae (PT) and it's processed products carbonized PT were selected as the representative case. Firstly, metabolomics data of 49 batches crude PT and carbonized PT was obtained by ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS). Then, metabolomics approaches were performed to screen for the potential markers that lead to the quality difference. Finally, chemometric methods were used to validate the accuracy of combinatorial quality markers. Thus, 42 compounds were identified from PT, 5 markers (isorhamnetin-3-O-(2G-α-L-rhamnosyl)-rutinoside, isorhamnetin-3-O-neohesperidoside, astragalin, kaempferol and umbelliferone) were successfully screened, identified, quantified and regarded as combinatorial quality markers for precise quality evaluation of crude and carbonized PT. It was demonstrated that the established comprehensively strategy provide an efficient tool for precise quality evaluation of natural products from the whole.

Health benefits and bioactive compounds of eggplant

Eggplant is a vegetable crop that is grown around the world and can provide significant nutritive benefits thanks to its abundance of vitamins, phenolics and antioxidants. In addition, eggplant has potential pharmaceutical uses that are just now becoming recognized. As compared to other crops in the Solanaceae, few studies have investigated eggplant's metabolic profile. Metabolomics and metabolic profiling are important platforms for assessing the chemical composition of plants and breeders are increasingly concerned about the nutritional and health benefits of crops. In this review, the historical background and classification of eggplant are shortly explained; then the beneficial phytochemicals, antioxidant activity and health effects of eggplant are discussed in detail.

HPLC-PDA Combined with Chemometrics for Quantitation of Active Components and Quality Assessment of Raw and Processed Fruits of Xanthium strumarium L

As a valuable herbal medicine, the fruits of Xanthium strumarium L. (Xanthii Fructus) have been widely used in raw and processed forms to achieve different therapeutic effects in practice. In this study, a comprehensive strategy was proposed for evaluating the active components in 30 batches of raw and processed Xanthii Fructus (RXF and PXF) samples, based on high-performance liquid chromatography coupled with photodiode array detection (HPLC-PDA). Twelve common peaks were detected and eight compounds of caffeoylquinic acids were simultaneously quantified in RXF and PXF. All the analytes were detected with satisfactory linearity (R² > 0.9991) over wide concentration ranges. Simultaneously, the chemically latent information was revealed by hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results suggest that there were significant differences between RXF and PXF from different regions in terms of the content of eight caffeoylquinic acids. Potential chemical markers for XF were found during processing by chemometrics.

On the effect of ultrasound-assisted atmospheric freeze-drying on the antioxidant properties of eggplant

The low operating temperatures employed in atmospheric freeze-drying permits an effective drying of heat sensitive products, without any impairment of their quality attributes. When using power ultrasound, the drying rate can be increased, thus reducing the process duration. However, ultrasound can also affect the product quality. The aim of this study was to evaluate the effect of various drying process variables, namely air temperature and velocity, ultrasound power and sample size, on the antioxidant properties of eggplant (Solanum melongena L.) samples. For this reason, drying experiments were carried out at different drying temperatures (-5, -7.5, -10 °C), power ultrasound levels (0, 25, 50 W; 21.9 kHz) and air velocities (2, 5 m s^-1) using different sample sizes (8.8 mm and 17.6 mm cube side). The ascorbic acid content (Jagota and Dani method), total phenolic content (Folin-Ciocalteau method), and the antioxidant capacity (FRAP method) of the dried products were considered as quality indicators of the dried samples. The increase in air velocity and temperature, as well as the sample size, significantly reduced the antioxidant potential of the dried samples (p-value < .05). For a given sample size, the application of ultrasound, at the acoustic power levels tested, did not produce significant effects on the antioxidant indicators considered. Temperature measurements inside the drying sample showed a non-negligible temperature rise when acoustic power was applied.

Metabolic Alterations in Two Cirsium Species Identified at Distinct Phenological Stages using UPLC-QTOF/MS

INTRODUCTION

Cirsium chanroenicum and C. setidens are commonly used both in traditional folk medicine and as a food source. The quality of different species of Cirsium at different harvest times is a function of their metabolite composition, which is determined by the phenological stage.

OBJECTIVE

We sought to determine the differences in the metabolite composition of two species of Cirsium during different phenological stages using ultra-performance liquid chromatography (UPLC) quadrupole time-of-flight (QTOF) mass spectrometry (MS).

METHODOLOGY

Cirsium chanroenicum and C. setidens plants were collected at the floral budding and full flowering stages. Metabolic profiles of Cirsium extracts were determined using UPLC-QTOF/MS to characterise the differences between phenological stages, and the major metabolites were quantified using UPLC-QTOF/MS-multiple reaction monitoring (MRM).

RESULTS

At the full flowering stage, the levels of phenolic acids as well as components of the phenylpropanoid pathway were increased. Flavonoids predominated at the full flowering stage in both species. The levels of coumaric acid, kaempferol, and pectolinarigenin differed between the two species of Cirsium. Overall, these results suggest that components of the phenylpropanoid metabolic pathway are upregulated in the full flowering stage in Cirsium, although we did observe some variation between the species.

CONCLUSION

These results will help elucidate the metabolic pathways related to the different phases of the vegetative cycle, and may help determine the optimal season for the harvest of Cirsium with the highest levels of bioactive compounds. Copyright © 2017 John Wiley & Sons, Ltd.

Optimization of ultrasound-assisted extraction of total monomeric anthocyanin (TMA) and total phenolic content (TPC) from eggplant (Solanum melongena L.) peel

The present study describes the extraction of total monomeric anthocyanin (TMA) and total phenolic content (TPC) from eggplant peel using ultrasonic treatments and methanol and 2-propanol as extraction solvents. The extraction yields were optimized by varying the solvent concentration, ultrasonic frequency, temperature and time of ultrasonic treatment. Box-Behnken design was used to investigate the effect of process variables on the ultrasound-assisted extraction. The results showed that for TPC extraction the optimal condition were obtained with a methanol concentration of 76.6%, 33.88 kHz ultrasonic frequency, a temperature of 69.4 °C and 57.5 min extraction time. For TMA the optimal condition were the following: 54.4% methanol concentration, 37 kHz, 55.1 °C and process time of 44.85 min.

Characterization of Polyphenols from Lycium ruthenicum Fruit by UPLC-Q-TOF/MS(E) and Their Antioxidant Activity in Caco-2 Cells

The fruit of Lycium ruthenicum Murr. (LRF) has long been used in folk medicine. Nevertheless, detailed information related to its polyphenol compositions remains scarce. In this study, we confirmed that the total phenolic and anthocyanin contents of LRF fruit extracts (LRFEs) were 4906.5 ± 60.6 mg of gallic acid equivalents/100 g DW and 787.6 ± 34.1 mg of cyanindin-3-glucoside equivalents/100 g DW, respectively. A characterization of LRFEs was performed by ultrahigh performance liquid chromatography/quadrupole time-of-flight mass spectrometry using an MS(E) data acquisition. A total of 26 polyphenols were tentatively identified, of which 19 represent the first reports of these polyphenols in LRFEs. Furthermore, the cellular antioxidant array showed that LRFEs could protect Caco-2 cells against H2O2-induced oxidative damage based on microscopic fluorometric imaging.

Lycibarbarspermidines A-O, New Dicaffeoylspermidine Derivatives from Wolfberry, with Activities against Alzheimer's Disease and Oxidation

Fifteen new dicaffeoylspermidine derivatives, lycibarbarspermidines A-O (1-15), were isolated from the fruit of Lycium barbarum (wolfberry). The structures were unambiguously determined by spectroscopic analyses and chemical methods. Dicaffeoylspermidine derivatives, a rare kind of plant secondary metabolites, are primarily distributed in the family of Solanaceae. Only six compounds were structurally identified, and all of them are acyclic aglycones. Compounds 1-15 are the first glycosidic products of dicaffeoylspermidine derivatives, and compounds 14-15 are the first cyclization products of dicaffeoylspermidine derivatives. Moreover, dicaffeoylspermidine derivatives were first isolated and identified from wolfberry. The short-term memory assay on a transgenic fly Alzheimer's disease (AD) model showed that 1-15 exhibited different levels of anti-AD activity. The oxygen radical absorbance capacity assay revealed that 1-15 all displayed antioxidant capacity. Both anti-AD and antioxidant functions are related to the effects of wolfberry. Therefore, dicaffeoylspermidine derivatives are considered beneficial constituents responsible for the antiaging, neuroprotective, anti-AD, and antioxidant effects of wolfberry.

Effect of cultivar and variety on phenolic compounds and antioxidant activity of cherry wine

To compare the influence of cultivar and variety on the phenolic compounds and antioxidant activity (AA) of cherry wines, total phenolic (TP), total flavonoid (TF), total anthocyanin (TA), total tannin (TT), five individual phenolic acids, and AA were determined. An ultra-performance liquid chromatography tandem mass spectrometry (HPLC-DAD/ESI-MS) method was developed for the determination of gallic acid (GAE), p-hydroxybenzoic acid (PHB), chlorogenic acid (CHL), vanillic acid (VAN), and caffeic acid (CAF). A principal component analysis (PCA) and a cluster analysis (CA) were used to analyze differences related to cultivar and variety. The TP, TF, TA, TT, and AA of samples sourced from the Shandong province of China were higher than those from the Jiangsu province. The PCA and CA results showed that phenolic compounds in cherry wines were closely related to cultivar and variety and that cultivar had more influence on the phenolic compounds of cherry wines than variety.

Assessment of the distribution of phenolic compounds and contribution to the antioxidant activity in Tunisian fig leaves, fruits, skins and pulps using mass spectrometry-based analysis

The qualitative and quantitative phenolic composition explains the differences in the antioxidant activity of fig leaves, fruits, pulps, and skins.

Mass spectrometric profiling of flavonoid glycoconjugates possessing isomeric aglycones

In fields such as food and nutrition science or plant physiology, interest in untargeted profiling of flavonoids continues to expand. The group of flavonoids encompasses several thousands of chemically distinguishable compounds, among which are a number of isobaric compounds with the same elemental composition. Thus, the mass spectrometric identification of these compounds is challenging, especially when reference standards are not available to support their identification. Many different types of isomers of flavonoid glycoconjugates are known, i.e. compounds that differ in their glycosylation position, glycan sequence or type of interglycosidic linkage. This work focuses on the mass spectrometric identification of flavonoid glycoconjugate isomers possessing the same glycan mass and differing only in their aglycone core. A non-targeted HPLC-ESI-MS/MS profiling method using a triple quadrupole MS is presented herein, which utilizes in-source fragmentation and a pseudo-MS(3) approach for the selective analysis of flavonoid glycoconjugates with isomeric/isobaric aglycones. A selective MRM-based identification of the in-source formed isobaric aglycone fragments was established. Additionally, utilizing the precursor scanning capability of the employed triple quadrupole instrument, the developed method enabled the determination of the molecular weight of the studied intact flavonoid glycoconjugate. The versatility of the method was proven with various types of flavonoid aglycones, i.e. anthocyanins, flavonols, flavones, flavanones and isoflavones, along with their representative glycoconjugates. The developed method was also successfully applied to a commercially available sour cherry sample, in which 16 different glycoconjugates of pelargonidin, genistein, cyanidin, kaempferol and quercetin could be tentatively identified, including a number of compounds containing isomeric/isobaric aglycones.

Reducing capacity, chlorogenic acid content and biological activity in a collection of scarlet (Solanum aethiopicum) and Gboma (S. macrocarpon) eggplants

Scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants are important vegetables in Sub-Saharan Africa. Few studies have been made on these crops regarding the diversity of phenolic content and their biological activity. We have studied the reducing activity, the chlorogenic acid and other phenolic acid contents in a collection of 56 accessions of scarlet eggplant, including the four cultivated groups (Aculeatum, Gilo, Kumba, Shum) and the weedy intermediate S. aethiopicum-S. anguivi types, as well as in eight accessions of gboma eggplant, including the cultivated S. macrocarpon and its wild ancestor, S. dasyphyllum. A sample of the accessions evaluated in this collection has been tested for inhibition of nitric oxide (NO) using macrophage cell cultures. The results show that there is a great diversity in both crops for reducing activity, chlorogenic acid content and chlorogenic acid peak area (% of total phenolic acids). Heritability (H²) for these traits was intermediate to high in both crops. In all samples, chlorogenic acid was the major phenolic acid and accounted for more than 50% of the chromatogram peak area. Considerable differences were found among and within groups for these traits, but the greatest values for total phenolics and chlorogenic acid content were found in S. dasyphyllum. In most groups, reducing activity was positively correlated (with values of up to 0.904 in the Aculeatum group) with chlorogenic acid content. Inhibition of NO was greatest in samples having a high chlorogenic acid content. The results show that both crops are a relevant source of chlorogenic acid and other phenolic acids. The high diversity found also indicates that there are good prospects for breeding new scarlet and gboma eggplant cultivars with improved content in phenolics and bioactive properties.