Phenolic profile of Sercial and Tinta Negra Vitis vinifera L. grape skins by HPLC–DAD–ESI-MSn: novel phenolic compounds in Vitis vinifera L. grape

This study represents the first phytochemical research of phenolic components of Sercial and Tinta Negra Vitis vinifera L. The phenolic profiles of Sercial and Tinta Negra V. vinifera L. grape skins (white and red varieties, respectively) were established using high performance liquid chromatography–diode array detection–electrospray ionisation tandem mass spectrometry (HPLC–DAD–ESI-MSn), at different ripening stages (véraison and maturity). A total of 40 phenolic compounds were identified, which included 3 hydroxybenzoic acids, 8 hydroxycinnamic acids, 4 flavanols, 5 flavanones, 8 flavonols, 4 stilbenes, and 8 anthocyanins. For the white variety, in both ripening stages, hydroxycinnamic acids and flavonols were the main phenolic classes, representing about 80% of the phenolic composition. For red variety, at véraison, hydroxycinnamic acids and flavonols were also the predominant classes (71%), but at maturity, anthocyanins represented 84% of the phenolic composition. As far as we know, 10 compounds were reported for the first time in V. vinifera L. grapes, namely protocatechuic acid-glucoside, p-hydroxybenzoyl glucoside, caftaric acid vanilloyl pentoside, p-coumaric acid-erythroside, naringenin hexose derivate, eriodictyol-glucoside, taxifolin-pentoside, quercetin-glucuronide-glucoside, malylated kaempferol-glucoside, and resveratrol dimer. These novel V. vinifera L. grape components were identified based on their MSn fragmentation profile. This data represents valuable information that may be useful to oenological management and to valorise these varieties as sources of bioactive compounds.

A comprehensive study on the phenolic profile of widely used culinary herbs and spices: Rosemary, thyme, oregano, cinnamon, cumin and bay

Herbs and spices have long been used to improve the flavour of food without being considered as nutritionally significant ingredients. However, the bioactive phenolic content of these plant-based products is currently attracting interest.In the present work, liquid chromatography coupled to high-resolution/accurate mass measurement LTQ-Orbitrap mass spectrometry was applied for the comprehensive identification of phenolic constituents of six of the most widely used culinary herbs (rosemary, thyme, oregano and bay) and spices (cinnamon and cumin). In this way, up to 52 compounds were identified in these culinary ingredients, some of them, as far as we know, for the first time. In order to establish the phenolic profiles of the different herbs and spices, accurate quantification of the major phenolics was performed by multiple reaction monitoring in a triple quadrupole mass spectrometer. Multivariate statistical treatment of the results allowed the assessment of distinctive features among the studied herbs and spices. (C) 2014 Elsevier Ltd. All rights reserved.

Home Cooking and Phenolics: Effect of Thermal Treatment and Addition of Extra Virgin Olive Oil on the Phenolic Profile of Tomato Sauces

Tomato products are a key component of the Mediterranean diet, which is strongly related to a reduced risk of cardiovascular events. The effect of cooking time (15, 30, 45, and 60 min) and the addition of extra virgin olive oil (5 and 10%) on the phenolic content of tomato sauces was monitored using liquid chromatography coupled to tandem mass spectrometry. Concentration of phenolics in the tomato sauces decreased during the cooking process, with the exception of caffeic acid and tyrosol. The main degradation observed was the oxidation of quercetin, since the hydroxy-function at the C-ring of this flavonoid is not blocked by a sugar moiety, unlike rutin. Higher levels of virgin olive oil in tomato sauce seemed to enhance the extraction of phenolic compounds from the tomato, leading to higher phenolic contents in the sauces. Thus, the food matrix containing the phenolic compounds plays a crucial role in determining their accessibility.

Variability of the phenolic profile of banana from Gran Canaria during maturation

[EN] The identification and quantification of phenolic compounds in bananas from Gran Canaria were carried out to examine changes in their profile during maturation. The phenolic composition of extracts derived from bananas was determined by using HPLC. The total phenolic contents were measured with Folin–Cicolteau`s phenol reagent. To quantify the total antioxidant capacity of banana extracts, we chose two methods commonly used: the percentage of inhibition of radical 1,1–diphenyl-2-picrylhydrazyl (DPPH) and the ferric reducing antioxidant power (FRAP assay). The antioxidant potential on banana extracts was found to increase during maturation in correlation whit the total phenol content.

Phenolic profile of Cynara scolymus L. and Silybum marianum(L.) Gaertn and related antimicrobial properties

Cynara scolymus L. (artichoke) and Silybum marianum (L.) Gaertn (milk thistle), belonging to the Asteraceae family, are medicinal plants vo.ith well-reported antioxidant and hepatoprotective effects. Widely consumed as infusions, these plants can also be found in several formulations to allow an easier consumption. The bioactivity of infusions, pills, and syrups based on artichoke and milk thistle was previously reported by our research group [1 ,2] and among the various phytochemicals present in these dietary supplements, phenolic compounds are pointed out as the most responsible for their beneficial properties. With the aim of studying the antimicrobial activity and possible relation vo.ith the phenolic composition, two different formulations of each plant were assessed (pills and syrups). The phenolic profiles were obtained by HPLC-DAD-ESIIMS, and the antimicrobial activity was performed with clinical isolates from hospitalized patients, namely Escherichia coli, Escherichia coli spectrum extended producer of P-lactarnases (ESBL), Proteus mirabilis, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus (MRSA). Vanillic acid (5.58 J.tg/g) and luteolin-7-0-glucoside (2.2 J.tg/g) were the most abundant compounds in artichoke syrup, that did not reveal antimicrobial activity against the studied strains, which could be due to their low concentrations. On the other hand, artichoke pills presented a prevalence of 5-0-caffeoylquinic (28.2 J.tg/g), 1,3-dicaffeoylquinic (24 J.tg/g), and 4-0-Caffeoylquinic acids (13.3 J.tg/g); revealing the capacity to inhibit MRSA vo.ith a MIC value of 1.9 mg!g. Regarding milk thistle, isorhamnetin-0-deoxyhexoside-0-hexoside, isorhamnetin-3-0-rutinoside, and isorhamnetin-0-deoxyhexoside-0-dihexoside were the major compounds detected in the syrup, in concentrations of 7.26, 5. 75, and 3.64 J.tg/g, respectively. This formulation proved to be able to inhibit the growth of E. coli, ESBL, MRSA and P. aeruginosa, with MIC values ranging from 0.2 to 1.3 mg!mL. Hydroxylated silibinin (1.565 J.!g/g) was the major flavonoid found in the pills, that revealed antimicrobial activity against ESBL, with a MIC value of 15 mg!mL, but did not inhibit the growth of the remaining bacteria None of the studied samples was able to inhibit P. mirabilis at the studied concentrations (1000 and 26.4 mg!mL for the syrups of artichoke and milk thistle, respectively; 150 mg/mL for both pills). Overall, the studied syrups and pills of artichoke and milk thistle revealed to be a good source of phenolic compounds, with some of these formulations revealing antimicrobial activity.

Phenolic profile and antimicrobial activity of dietary supplements based on Cochlospermum angolensis Welw.

Cochlospermum angolensis Welw. (borututu) is a widespread tree in Angola that belongs to the Cochlospermaceae family. Its bark infusion is used in the traditional medicine of Angola for the treatment of jaundice, hepatic diseases and for the prophylaxis of malaria [1]. In the present work, three formulations based on this plant (infusion, pills, and syrup) were characterized by HPLC-DAD-ESI/MS regarding phenolic composition, and evaluated by their in vitro antimicrobial activity against isolates of multiresistant bacteria (Escherichia coli, Escherichia coli spectrum extended producer of β-lactamases (ESBL), Proteus mirabilis, methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa). The infusion and pills revealed the highest variety of phenolic compounds, with eleven compounds identified. Protocatechuic acid was only present in infusions, being the most abundant compound, while (epi)gallocatechin-O-gallate and eucaglobulin/globulusin were the main molecules identified in pills and syrup, respectively. Methyl ellagic acids, eucaglobulin/globulusin B (Fig. 1) and (epi)gallocatechin-O-gallate were found in all the formulations. The infusion revealed antimicrobial activity against all the studied bacteria with the exception of P. mirabilis whereas the pills revealed activity in E. coli ESBL and MRSA. No significant antimicrobial activity was detected in the syrup, in agreement with its low concentrations of phenolic compounds. None of the tested formulations inhibited P. mirabilis. Considering the obtained results, C. angolensis infusion can be considered a good source of phenolic compounds as well as a good antimicrobial agent.

Profile Of Phenolic Compounds Of Brazilian Virgin Olive Oils By Rapid Resolution Liquid Chromatography Coupled To Electrospray Ionisation Time-of-flight Mass Spectrometry (rrlc-esi-tof-ms).

In recent years, agronomical researchers began to cultivate several olive varieties in different regions of Brazil to produce virgin olive oil (VOO). Because there has been no reported data regarding the phenolic profile of the first Brazilian VOO, the aim of this work was to determine phenolic contents of these samples using rapid-resolution liquid chromatography coupled to electrospray ionisation time-of-flight mass spectrometry. 25 VOO samples from Arbequina, Koroneiki, Arbosana, Grappolo, Manzanilla, Coratina, Frantoio and MGS Mariense varieties from three different Brazilian states and two crops were analysed. It was possible to quantify 19 phenolic compounds belonging to different classes. The results indicated that Brazilian VOOs have high total phenolic content because the values were comparable with those from high-quality VOOs produced in other countries. VOOs from Coratina, Arbosana and Grappolo presented the highest total phenolic content. These data will be useful in the development and improvement of Brazilian VOO.

Phenolic compounds from olive mill wastes: Health effects, analytical approach and application as food antioxidants

Background Over the years, food industry wastes have been the focus of a growing interest due to their content in high added-value compounds. A good example are the olive oil by-products (OOBP), which retain a great amount of phenolic compounds during olive oil production. Their structure and biological properties justify their potential use as antioxidants in other food products. The efficient recovery of phenolic compounds has been extensively studied and optimized in order to maximize their reintroduction in the food chain and contribute to a higher valorization and better management of wastes from olive oil industry. Scope and approach This paper reviews the most representative phenolic compounds described in OOBP and their biological properties. New extraction procedures to efficiently recover these compounds and the most advanced chromatographic techniques that have been used for a better understanding of the phenolic profile of these complex matrices are also referred. Finally, this paper reports the main applications of OOBP, with emphasis on their phenolic content as natural antioxidants for food applications. Key findings and conclusions Besides their antioxidant activity, phenolic compounds from OOBP have also shown antimicrobial and antitumoral properties. Their application as food antioxidants requires new extraction techniques, including the use of non-toxic solvents and, in a pilot scale, the use of filters and adsorbent resins. The inclusion of phenolic compounds from OOBP in some food matrices have improved not only their antioxidant capacity but also their sensory attributes.

Characterization of the phenolic and antioxidant profiles of selected culinary herbs and spices: caraway, turmeric, dill, marjoram and nutmeg

Culinary herbs and spices have long been considered essentially as flavor enhancers or preservatives, with little attention given to their potential health-promoting properties. Nevertheless, recent research has shown them to be significant dietary sources of bioactive phenolic compounds. Despite noteworthy efforts performed in recent years to improve our knowledge of their chemical composition, a detailed phenolic profile of these plant-based products is still lacking. In the present work, antioxidant activities and phenolic composition of five herbs and spices, namely caraway, turmeric, dill, marjoram and nutmeg, have been studied. The use of liquid chromatography coupled to LTQ-Orbitrap mass spectrometry enabled the identification of up to 42 phenolic compounds. To the best of our knowledge, two of them, apigenin-C-hexoside-C-pentoside and apigenin-C-hexoside-C-hexoside have not been previously reported in turmeric. Qualitative and quantitative differences were observed in polyphenol profiles, with the highest phenolic content found in caraway. Multivariate statistical treatment of the results allowed the detection of distinctive features among the studied herbs and spices.

Phenolic composition of the berry parts of hybrid grape cultivar BRS Violeta (BRS Rubea×IAC 1398-21) using HPLC-DAD-ESI-MS/MS

The grape is considered a major source of phenolic compounds when compared to other fruits and vegetables, however, there are many cultivars with distinct characteristics directly linked to phenolic profile. Thus, the present study aimed to identify and quantify, for the first time and in detail, the phenolic compounds present in the skin, flesh and seeds of BRS Violeta grape berry using combination of SPE methodologies and analytical HPLC-DAD-ESI-MS/MS. The study was extended to the different berry parts and the most important grape and wine phenolic families, and has revealed interesting features. Violeta grape has a very thick skin (46% of grape weight) that accumulated the most of grape phenolic compounds: great amount of anthocyanins (3930. mg/kg, as malvidin 3,5-diglucoside), together with also important amounts of flavonols (150. mg/kg, as quercetin 3-glucoside), hydroxycinnamic acid derivatives (HCAD; 120. mg/kg, as caftaric acid), and proanthocyanidins (670. mg/kg, as (+)-catechin); in contrast, it seems to be a low resveratrol producer. Violeta grape seeds accounted for similar proportions of low molecular weight flavan-3-ols (mainly monomers; 345. mg/kg, as (+)-catechin) and proanthocyanidins (480. mg/kg, as (+)-catechin). Violeta grape is a teinturier cultivar, but it only contained traces of anthocyanins and low amounts of all the other phenolic types in its red-colored flesh. The anthocyanin composition of Violeta grape was dominated by anthocyanidin 3,5-diglucosides (90%). Within flavonols, myricetin-type predominated and kaempferol-type was missing. In addition to expected hydroxycinnamoyl-tartaric acids, several isomeric esters of caffeic and p-coumaric acids with hexoses were tentatively identified, accounting for relevant proportions within the pool of HCAD. Although pending of further confirmation over successive vintages, the aforementioned results suggest that BRS Violeta grape cultivar could be considered an interesting candidate for the elaboration of highly colored and antioxidant-rich grape juices and wines. © 2013 Elsevier Ltd.

Characterization of the phenolic and antioxidant profiles of selected culinary herbs and spices: caraway, turmeric, dill, marjoram and nutmeg

Culinary herbs and spices have long been considered essentially as flavor enhancers or preservatives, with little attention given to their potential health-promoting properties. Nevertheless, recent research has shown them to be significant dietary sources of bioactive phenolic compounds. Despite noteworthy efforts performed in recent years to improve our knowledge of their chemical composition, a detailed phenolic profile of these plant-based products is still lacking. In the present work, antioxidant activities and phenolic composition of five herbs and spices, namely caraway, turmeric, dill, marjoram and nutmeg, have been studied. The use of liquid chromatography coupled to LTQ-Orbitrap mass spectrometry enabled the identification of up to 42 phenolic compounds. To the best of our knowledge, two of them, apigenin-C-hexoside-C-pentoside and apigenin-C-hexoside-C-hexoside have not been previously reported in turmeric. Qualitative and quantitative differences were observed in polyphenol profiles, with the highest phenolic content found in caraway. Multivariate statistical treatment of the results allowed the detection of distinctive features among the studied herbs and spices.

Quali-quantitative study of the phenolic and polyphenolic compounds and their antioxidant capacity in vegetal matrix processed with different technologies

Food technologies today mean reducing agricultural food waste, improvement of food security, enhancement of food sensory properties, enlargement of food market and food economies. Food technologists must be high-skilled technicians with good scientific knowledge of food hygiene, food chemistry, industrial technologies and food engineering, sensory evaluation experience and analytical chemistry. Their role is to apply the modern vision of science in the field of human nutrition, rising up knowledge in food science. The present PhD project starts with the aim of studying and improving frozen fruits quality. Freezing process in very powerful in preserve initial raw material characteristics, but pre-treatment before the freezing process are necessary to improve quality, in particular to improve texture and enzymatic activity of frozen foods. Osmotic Dehydration (OD) and Vacuum Impregnation (VI), are useful techniques to modify fruits and vegetables composition and prepare them to freezing process. These techniques permit to introduce cryo-protective agent into the food matrices, without significant changes of the original structure, but cause a slight leaching of important intrinsic compounds. Phenolic and polyphenolic compounds for example in apples and nectarines treated with hypertonic solutions are slightly decreased, but the effect of concentration due to water removal driven out from the osmotic gradient, cause a final content of phenolic compounds similar to that of the raw material. In many experiment, a very important change in fruit composition regard the aroma profile. This occur in strawberries osmo-dehydrated under vacuum condition or under atmospheric pressure condition. The increment of some volatiles, probably due to fermentative metabolism induced by the osmotic stress of hypertonic treatment, induce a sensory profile modification of frozen fruits, that in some way result in a better acceptability of consumer, that prefer treated frozen fruits to untreated frozen fruits. Among different processes used, a very interesting result was obtained with the application of a osmotic pre-treatment driven out at refrigerated temperature for long time. The final quality of frozen strawberries was very high and a peculiar increment of phenolic profile was detected. This interesting phenomenon was probably due to induction of phenolic biological synthesis (for example as reaction to osmotic stress), or to hydrolysis of polymeric phenolic compounds. Aside this investigation in the cryo-stabilization and dehydrofreezing of fruits, deeper investigation in VI techniques were carried out, as studies of changes in vacuum impregnated prickly pear texture, and in use of VI and ultrasound (US) in aroma enrichment of fruit pieces. Moreover, to develop sensory evaluation tools and analytical chemistry determination (of volatiles and phenolic compounds), some researches were bring off and published in these fields. Specifically dealing with off-flavour development during storage of boiled potato, and capillary zonal electrophoresis (CZE) and high performance liquid chromatography (HPLC) determination of phenolic compounds.

Phenolic acids in Australian Melaleuca, Guioa, Lophostemon, Banksia and Helianthus honeys and their potential for floral authentication

Eight phenolic acids and two abscisic acid isomers in Australian honeys from five botanical species (Melaleuca, Guioa, Lophostemon, Banksia and Helianthus) have been analyzed in relation to their botanical origins. Total phenolic acids present in these honeys range from 2.13 mg/100 g sunflower (Helianthus annuus) honey to 12.11 mg/100 g tea tree (Melaleuca quinquenervia) honey, with amounts of individual acids being various. Tea tree honey shows a phenolic profile of gallic, ellagic, chlorogenic and coumaric acids, which is similar to the phenolic profile of an Australian Eucalyptus honey (bloodwood or Eucalyptus intermedia honey). The main difference between tea tree and bloodwood honeys is the contribution of chlorogenic acid to their total phenolic profiles. In Australian crow ash (Guioa semiglauca) honey, a characteristic phenolic profile mainly consisting of gallic acid and abscisic acid could be used as the floral marker. In brush box (Lophostemon conferta) honey, the phenolic profile, comprising mainly gallic acid and ellagic acid, could be used to differentiate this honey not only from the other Australian non-Eucalyptus honeys but also from a Eucalyptus honey (yellow box or Eucalyptus melliodora honey). However, this Eucalyptus honey could not be differentiated from brush box honey based only on their flavonoid profiles. Similarly, the phenolic profile of heath (Banksia ericifolia) honey, comprising mainly gallic acid, an unknown phenolic acid (Phl) and coumaric acid, could also be used to differentiate this honey from tea tree and bloodwood honeys, which have similar flavonoid profiles. Coumaric acid is a principal phenolic acid in Australian sunflower honey and it could thus be used together with gallic acid for the authentication. These results show that the HPLC analysis of phenolic acids and abscisic acids in Australian floral honeys Could assist the differentiation and authentication of the honeys. © 2005 Elsevier Ltd. All rights reserved.

Optimization of microwave-assisted extration of phenolic compounds from tomao by full factorial design coupled with response surface methodology

Tomato (Lycopersicon esculentum Mill.), apart from being a functional food rich in carotenoids, vitamins and minerals, is also an important source of phenolic compounds [1 ,2]. As antioxidants, these functional molecules play an important role in the prevention of human pathologies and have many applications in nutraceutical, pharmaceutical and cosmeceutical industries. Therefore, the recovery of added-value phenolic compounds from natural sources, such as tomato surplus or industrial by-products, is highly desirable. Herein, the microwave-assisted extraction of the main phenolic acids and flavonoids from tomato was optimized. A S-Ieve! full factorial Box-Behnken design was implemented and response surface methodology used for analysis. The extraction time (0-20 min), temperature (60-180 "C), ethanol percentage (0-100%), solidlliquid ratio (5-45 g/L) and microwave power (0-400 W) were studied as independent variables. The phenolic profile of the studied tomato variety was initially characterized by HPLC-DAD-ESIIMS [2]. Then, the effect of the different extraction conditions, as defined by the used experimental design, on the target compounds was monitored by HPLC-DAD, using their UV spectra and retention time for identification and a series of calibrations based on external standards for quantification. The proposed model was successfully implemented and statistically validated. The microwave power had no effect on the extraction process. Comparing with the optimal extraction conditions for flavonoids, which demanded a short processing time (2 min), a low temperature (60 "C) and solidlliquid ratio (5 g/L), and pure ethanol, phenolic acids required a longer processing time ( 4.38 min), a higher temperature (145.6 •c) and solidlliquid ratio (45 g/L), and water as extraction solvent. Additionally, the studied tomato variety was highlighted as a source of added-value phenolic acids and flavonoids.

HPLC-DAD-ESI/MS analysis of phenolic compounds in four tomato varieties and evaluation of the antioxidant capacity

Tomato (Lycopersicon esculentum L.) is the second most important vegetable crop worldwide and a key component in the so-called “Mediterranean diet”. In the Northeastern region of Portugal, local populations still prefer to consume traditional tomato varieties which they find very tasty and healthy, as they are grown using extensive farming techniques. A previous study of our research team described the nutritional value of the round (batateiro), long (comprido), heart (coração) and yellow (amarelo) tomato varieties [1], but the phenolic profile was unknown until now. Thus, the objective of this study was to characterize the phenolic profiles of these four tomato farmers’ varieties by using HPLC-DAD-ESI/MS and evaluate its antioxidant capacity through four in vitro assays based on different reaction mechanisms. A cis p-coumaric acid derivative was the most abundant compound in yellow and round tomato varieties, while 4-O-caffeolyquinic acid was the most abundant in long and heart varieties. The most abundant flavonoid was quercetin pentosylrutinoside in the four tomato varieties. Yellow tomato presented the highest levels of phenolic compounds, including phenolic acids and flavonoids, but the lowest antioxidant activity. In turn, the round tomato gave the best results in all the antioxidant activity assays. This study demonstrated that these tomato farmers’ varieties are a source of phenolic compounds, mainly phenolic acid derivatives [2], and possess high antioxidant capacity [1]; being thus key elements in the diet to prevent chronic degenerative diseases associated to oxidative stress, such as cancer and coronary artery disease.