Conventional extraction of fucoidan from Irish brown seaweed Fucus vesiculosus followed by ultrasound-assisted depolymerization.

Fucoidan has attracted considerable attention from scientists and pharmaceutical companies due to its antioxidant, anticoagulant, anti-inflammatory, anti-tumor, and health-enhancing properties. However, the extraction of fucoidan from seaweeds often involves the use of harsh chemicals, which necessitates the search for alternative solvents. Additionally, the high viscosity and low cell permeability of high molecular weight (Mw) fucoidan can limit its effectiveness in drug action, while lower Mw fractions exhibit increased biological activity and are also utilized as dietary supplements. The study aimed to (1) extract fucoidan from the seaweed Fucus vesiculosus (FV) using an environmentally friendly solvent and compare it with the most commonly used extraction solvent, hydrochloric acid, and (2) assess the impact of ultrasound-assisted depolymerization on reducing the molecular weight of the fucoidan extracts and examine the cytotoxic effect of different molecular weight fractions. The findings indicated that the green depolymerization solvent, in conjunction with a brief ultrasound treatment, effectively reduced the molecular weight. Moreover, a significant decrease in cell viability was observed in selected samples, indicating potential anticancer properties. As a result, ultrasound was determined to be an effective method for depolymerizing crude fucoidan from Fucus Vesiculosus seaweed.

Antioxidant Guided Fractionation of Blackberry Polyphenols Show Synergistic Role of Catechins and Ellagitannins.

In the present study, blackberry extract was prepared using a previously optimized solid-liquid extraction method in 70% aqueous acetone aimed at the recovery of its principal phenolics. Subsequently, 0.5 g of freeze-dried extract was subjected to flash chromatography fractionation, which was conducted on a C18 column using a binary solvent system of water and methanol at 10 mL/min. The total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) activities of the obtained 42 flash fractions were determined, and a strong positive correlation (r ≥ 0.986) was exhibited among them. Furthermore, the graph of the antioxidant indices of the flash fractions resembled the flash chromatogram, suggesting a good correlation among the compounds within the chromatographic peaks and the antioxidant indices. LC-MS/MS identified as many 28 phenolics, including cinnamtannin A2 reported for the first time in blackberries. This study further established the role of dominant anthocyanins (cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside), but uniquely those of ellagitannins and catechins on the antioxidant capacity of blackberries.

High-Pressure Processing and Ultrasonication of Minimally Processed Potatoes: Effect on the Colour, Microbial Counts, and Bioactive Compounds.

HPP at 600 MPa alone, and in combination with US at 20 kHz (200 W), was applied to minimally processed potatoes of two commonly grown cultivars in Ireland. Changes in colour and microbial load (Enterobacteriaceae, total aerobic count, Salmonella, yeasts, and moulds) were monitored in vacuum-packaged potatoes during 14 days of storage at 4 °C. HPP and HPP/US significantly (p < 0.05) affected the colour parameters a*, b*, L*, and ΔE of minimally processed potatoes compared to the controls. Microbial growth was delayed in most of the treated samples with respect to those untreated (controls), while HPP completely inactivated Enterobacteriaceae in both cultivars. Total phenolic content and antioxidant activities were not altered in the treated samples of both varieties when compared to the controls. The levels of chlorogenic acid, ferulic acid, and caffeic acid were decreased after both treatments, with a significant (p < 0.05) increase in quinic acid in the treated samples as opposed to those untreated. A significant (p < 0.05) decrease in the levels of glycoalkaloids, namely α-chaconine and α-solanine, in HPP- and HPP/US-treated potatoes was also observed. These findings suggest that HPP and US can extend the shelf-life of minimally processed potatoes with a negligible impact on their antioxidant activity and phenolic content.

Advances in Azorella glabra Wedd. Extract Research: In Vitro Antioxidant Activity, Antiproliferative Effects on Acute Myeloid Leukemia Cells and Bioactive Compound Characterization.

Azorella glabra Wedd. (AG) is traditionally used to treat gonorrhea or kidney's problems. The antioxidant, antidiabetic, anticholinesterase and in vitro antitumor activities of AG extracts were recently reported. The aim of this work was to investigate anti-leukemic properties of AG chloroform fraction (AG CHCl3) and of its ten sub-fractions (I-X) and to identify their possible bioactive compounds. We determined their in vitro antioxidant activity using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), nitric oxide (NO) and superoxide anion (SO) assays, and their phytochemical profile by spectrophotometric and LC-MS/MS techniques. I-X action on two acute myeloid leukemia (AML) cell lines viability, apoptosis and cell cycle were evaluated by MTS, western blotting and cytofluorimetric assays. Different polyphenol, flavonoid and terpenoid amount, and antioxidant activity were found among all samples. Most of I-X induced a dose/time dependent reduction of cell viability higher than parent extract. IV and VI sub-fractions showed highest cytotoxic activity and, of note, a negligible reduction of healthy cell viability. They activated intrinsic apoptotic pathway, induced a G0/G1 block in leukemic cells and, interestingly, led to apoptosis in patient AML cells. These activities could be due to mulinic acid or azorellane terpenoids and their derivatives, tentatively identified in both IV and VI. In conclusion, our data suggest AG plant as a source of potential anti-AML agents.

Phytochemicals of Minthostachys diffusa Epling and Their Health-Promoting Bioactivities.

The genus Minthostachys belonging to the Lamiaceae family, and is an important South American mint genus used commonly in folk medicine as an aroma in cooking. The phytochemical-rich samples of the aerial parts of Minthostachys diffusa Epling. were tested for pharmacological and health-promoting bioactivities using in vitro chemical and enzymatic assays. A range of radical scavenging activities of the samples against biological radicals such as nitric oxide and superoxide anion and against synthetic 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, the ferric reducing antioxidant power and the lipid peroxidation inhibition were determined and ranked using the 'relative antioxidant capacity index' (RACI). The ethyl acetate fraction showed the highest RACI of +1.12. Analysis of the various fractions' inhibitory ability against enzymes involved in diabetes (α-amylase and α-glucosidase), and against enzymes associated with Parkinson's or Alzheimer's diseases (acetylcholinesterase and butyrylcholinesterase) also suggested that the ethyl acetate fraction was the most active. Liquid chromatography-tandem mass spectrometry analysis of the ethyl acetate fraction showed more than 30 polyphenolic compounds, including triterpenes. The inhibitory cholinesterase effects of the triterpenes identified from M. diffusa were further analysed by in silico docking of these compounds into 3D-structures of acetylcholinesterase and butyrylcholinesterase. This is the first study on pharmacological activities and phytochemical profiling of the aerial parts of M. diffusa, showing that this plant, normally used as food in South America, is also rich in health-promoting phytochemicals.

Antioxidant, Antidiabetic, and Anticholinesterase Activities and Phytochemical Profile of Azorella glabra Wedd.

Oxidative stress is involved in different diseases, such as diabetes and neurodegenerative diseases. The genus Azorella includes about 70 species of flowering plant species; most of them are commonly used as food and in particular as a tea infusion in the Andean region of South America in folk medicine to treat various chronic diseases. Azorella glabra Wedd. aerial parts were firstly analyzed for their in vitro antioxidant activity using different complementary assays. In particular, radical scavenging activity was tested against biological neutral radical DPPH; ferric reducing power and lipid peroxidation inhibitory capacity (FRAP and Beta-Carotene Bleaching tests) were also determined. The Relative Antioxidant Capacity Index (RACI) was used to compare data obtained by different assays. Then, the inhibitory ability of samples was investigated against α-amylase and α-glucosidase enzymes involved in diabetes and against acetylcholinesterase and butyrylcholinesterase enzymes considered as strategy for the treatment of Parkinson's or Alzheimer's diseases. Moreover, the phytochemical profile of the sample showing the highest RACI (1.35) and interesting enzymatic activities (IC50 of 163.54 ± 9.72 and 215.29 ± 17.10 µg/mL in α-glucosidase and acetylcholinesterase inhibition, respectively) was subjected to characterization and quantification of its phenolic composition using LC-MS/MS analysis. In fact, the ethyl acetate fraction derived from ethanol extract by liquid/liquid extraction showed 29 compounds, most of them are cinnamic acid derivatives, flavonoid derivatives, and a terpene. To the best of our knowledge, this is the first report about the evaluation of significant biological activities and phytochemical profile of A. glabra, an important source of health-promoting phytochemicals.

Antioxidant Activity and Phytochemical Characterization of Senecio clivicolus Wedd.

Antioxidant phytochemicals play a key role in oxidative stress control and in the prevention of related disorders, such as premature aging, degenerative diseases, diabetes, and cancer. The aim of this study was to investigate the potential antioxidant activity and the phytochemical profile of Senecio clivicolus Wedd., a perennial shrub, belonging to the Asteraceae family. Despite the wide interest of this family, this specie has not been investigated yet. S. clivicolus aerial parts were extracted with 96% ethanol. Then, the ethanol extract was fractionated by liquid/liquid extraction using an increasing solvents polarity. Total polyphenol and terpenoid contents were measured. Moreover, the antioxidant activity was evaluated by six different complementary in vitro assays. The Relative Antioxidant Capacity Index (RACI) was used to compare data obtained by different tests. The sample showing the highest RACI was subjected to characterization and quantitation of its phenolic composition using LC-MS/MS analysis. The ethyl acetate fraction, investigated by LC-MS/MS analysis, showed 30 compounds, most of them are chlorogenic acid and flavonoid derivatives. To the best of our knowledge, this is the first report about the evaluation of antioxidant activity and phytochemical profile of S. clivicolus, underlying the importance of this species as a source of health-promoting phytochemicals.

Meta-Analysis of the Effects of Foods and Derived Products Containing Ellagitannins and Anthocyanins on Cardiometabolic Biomarkers: Analysis of Factors Influencing Variability of the Individual Responses.

Understanding interindividual variability in response to dietary polyphenols remains essential to elucidate their effects on cardiometabolic disease development. A meta-analysis of 128 randomized clinical trials was conducted to investigate the effects of berries and red grapes/wine as sources of anthocyanins and of nuts and pomegranate as sources of ellagitannins on a range of cardiometabolic risk biomarkers. The potential influence of various demographic and lifestyle factors on the variability in the response to these products were explored. Both anthocyanin- and ellagitannin-containing products reduced total-cholesterol with nuts and berries yielding more significant effects than pomegranate and grapes. Blood pressure was significantly reduced by the two main sources of anthocyanins, berries and red grapes/wine, whereas waist circumference, LDL-cholesterol, triglycerides, and glucose were most significantly lowered by the ellagitannin-products, particularly nuts. Additionally, we found an indication of a small increase in HDL-cholesterol most significant with nuts and, in flow-mediated dilation by nuts and berries. Most of these effects were detected in obese/overweight people but we found limited or non-evidence in normoweight individuals or of the influence of sex or smoking status. The effects of other factors, i.e., habitual diet, health status or country where the study was conducted, were inconsistent and require further investigation.

Higher Antioxidant Activity, Total Flavonols, and Specific Quercetin Glucosides in Two Different Onion (Allium cepa L.) Varieties Grown under Organic Production: Results from a 6-Year Field Study.

We carried out a 6-year study to assess the effect of conventional, organic, and mixed cultivation practices on bioactive compounds (flavonoids, anthocyanins) and antioxidant capacity in onion. Total flavonoids, total anthocyanins, individual flavonols, individual anthocyanins, and antioxidant activity were measured in two varieties ('Hyskin' and 'Red Baron') grown in a long-term split-plot factorial systems comparison trial. This is the first report of repeated measurements of bioactive content over an extensive time period in a single crop type within the same trial. Antioxidant activity (DPPH and FRAP), total flavonol content, and levels of Q 3,4' D and Q 3 G were higher in both varieties under fully organic compared to fully conventional management. Total flavonoids were higher in 'Red Baron' and when onions were grown under organic soil treatment. Differences were primarily due to different soil management practices used in organic agriculture rather than pesticide/ herbicide application.

Evaluation of polyphenolic content and antioxidant activity in two onion varieties grown under organic and conventional production systems.

BACKGROUND: Onions contain a number of bioactive compounds, in particular polyphenols. They are rich sources of such compounds in the human diet and offer significant health benefits to the consumer. Demand for organic crops is steadily increasing partly based on the expected health benefits of organic food consumption. The current study examines the influence of organic and conventional crop management practices on bioactive polyphenolic content of onion. RESULTS: We examined the effect of conventional, organic, and mixed cultivation practices on the content of total phenolics, total flavonoids and antioxidant activity in two varieties of onion grown over 4 years in a split-plot factorial systems comparison trial. Levels of total phenolics and total flavonoids showed a significant year-on-year variation and were significantly different between organic and conventional production systems. The levels of total phenolics, total flavonoids and antioxidant activity in general were significantly higher (P < 0.05) under fully organic compared to fully conventional management. CONCLUSION: Organic cultivation practices resulted in significantly higher levels of potential bioactive compounds in onion. © 2016 Society of Chemical Industry.

Antioxidant-guided isolation and mass spectrometric identification of the major polyphenols in barley (Hordeum vulgare) grain.

In the present study, the relative contribution of individual/classes of polyphenols in barley, to its antioxidant properties, was evaluated. Flash chromatography was used to fractionate the total polyphenol extract of Irish barley cultivar 'Irina', and fractions with highest antioxidant properties were identified using total phenolic content and three in vitro antioxidant assays: DPPH, FRAP, and ORAC. Flavanols (catechin, procyanidin B, prodelphinidin B, procyanidin C) and a novel substituted flavanol (catechin dihexoside, C27H33O16(-), m/z 613.17), were identified as constituents of the fraction with highest antioxidant capacity. Upon identification of phenolics in the other active fractions, the order of most potent contributors to observed antioxidant capacity of barley extract were, flavanols>flavonols (quercetin)>hydroxycinnamic acids (ferulic, caffeic, coumaric acids). The most abundant polyphenol in the overall extract was ferulic acid (277.7µg/gdw barley), followed by procyanidin B (73.7µg/gdw barley).

Effect of Drying Methods on the Steroidal Alkaloid Content of Potato Peels, Shoots and Berries.

The present study has found that dried potato samples yielded significantly higher levels of steroidal alkaloids such as α-solanine and α-chaconine than the corresponding fresh samples, as determined by the UPLC-MS/MS technique. Among the drying techniques used, air drying had the highest effect on steroidal alkaloid contents, followed by freeze drying and vacuum oven drying. There was no significant difference between the freeze dried and vacuum oven dried samples in their α-chaconine contents. However, freeze dried potato shoots and berries had significantly higher α-solanine contents (825 µg/g dry weight (DW) in shoots and 2453 µg/g DW in berries) than the vacuum oven dried ones (325 µg/g dry weight (DW) in shoots and 2080 µg/g DW in berries). The kinetics of steroidal alkaloid contents of potato shoots during air drying were monitored over a period of 21 days. Both α-solanine and α-chaconine content increased to their maximum values, 875 µg/g DW and 3385 µg/g DW, respectively, after 7 days of drying. The steroidal alkaloid contents of the shoots decreased significantly at day 9, and then remained unchanged until day 21. In line with the potato shoots, air dried potato tuber peels also had higher steroidal alkaloid content than the freeze dried and vacuum oven dried samples. However, a significant decrease of steroidal alkaloid content was observed in air dried potato berries, possibly due to degradation during slicing of the whole berries prior to air drying. Remarkable variation in steroidal alkaloid contents among different tissue types of potato plants was observed with the potato flowers having the highest content.

Optimisation and validation of ultra-high performance liquid chromatographic-tandem mass spectrometry method for qualitative and quantitative analysis of potato steroidal alkaloids.

An ultra-high performance liquid chromatographic-tandem mass spectrometry (UHPLC-MS/MS) method for quantification of potato steroidal alkaloids, namely α-solanine, α-chaconine, solanidine and demissidine was developed and validated. Three different column chemistries, i.e. ethylene bridged hybrid (BEH) C18, hydrophilic lipophilic interaction and amide columns, were assessed. The BEH C18 column showed best separation and sensitivity for the alkaloids. Validation data (inter-day and intra-day combined) for accuracy and recovery ranged from 94.3 to 107.7% and 97.0 to 103.5%, respectively. The accuracy data were within the acceptable range of 15% as outlined in the United States Food and Drug Administration (USFDA) guidelines. The recovery data were consistent and reproducible with a coefficient of variation (CV) ranging from 6.2 to 9.7%. In addition, precision of the method also met the criteria of the USFDA with CV values lower than 15% even at lower limit of quantification (LLOQ), while the permissible variation is considered acceptable below 20%. The limit of detection and LLOQ of the four alkaloids were in the range of 0.001-0.004µg/mL whereas the linearities of the standard curves were between 0.980 and 0.995.

A Review of Extraction and Analysis of Bioactives in Oat and Barley and Scope for Use of Novel Food Processing Technologies.

Oat and barely are cereal crops mainly used as animal feed and for the purposes of malting and brewing, respectively. Some studies have indicated that consumption of oat and barley rich foods may reduce the risk of some chronic diseases such as coronary heart disease, type II diabetes and cancer. Whilst there is no absolute consensus, some of these benefits may be linked to presence of compounds such as phenolics, vitamin E and ß-glucan in these cereals. A number of benefits have also been linked to the lipid component (sterols, fatty acids) and the proteins and bioactive peptides in oats and barley. Since the available evidence is pointing toward the possible health benefits of oat and barley components, a number of authors have examined techniques for recovering them from their native sources. In the present review, we summarise and examine the range of conventional techniques that have been used for the purpose of extraction and detection of these bioactives. In addition, the recent advances in use of novel food processing technologies as a substitute to conventional processes for extraction of bioactives from oats and barley, has been discussed.

Cardioprotective potential of Irish macroalgae: generation of glycine betaine and dimethylsulfoniopropionate containing extracts by accelerated solvent extraction.

Accelerated solvent extraction (ASE®) was used to generate 18 macroalgal extracts from Irish seaweeds. The glycine betaine and dimethylsulfoniopriopionate content of the generated ASE® extracts were estimated using (1)H-NMR and confirmed for selected extracts using ultra performance liquid chromatography and mass spectrometry. Dimethylsulfoniopriopionate was only identified in the ASE® extract generated from Codium fragile ISCG0029. Glycine betaine was identified in the ASE® extract generated from Ulva intestinalis ISCG0356 using (1)H-NMR. Mass spectrometry analysis found that the seaweed species Cytoseira nodicaulis ISCG0070, Cytoseira tamariscofolia ISCG0283, and Polysiphonia lanosa ISCG0462 also had a glycine betaine content that ranged from 1.39 ng/ml to 105.11 ng/ml. Generated ASE® macroalgal extracts have potential for use as functional food ingredients in food products.

Recovery of steroidal alkaloids from potato peels using pressurized liquid extraction.

A higher yield of glycoalkaloids was recovered from potato peels using pressurized liquid extraction (1.92 mg/g dried potato peels) compared to conventional solid-liquid extraction (0.981 mg/g dried potato peels). Response surface methodology deduced the optimal temperature and extracting solvent (methanol) for the pressurized liquid extraction (PLE) of glycoalkaloids as 80 °C in 89% methanol. Using these two optimum PLE conditions, levels of individual steroidal alkaloids obtained were of 597, 873, 374 and 75 µg/g dried potato peel for α-solanine, α-chaconine, solanidine and demissidine respectively. Corresponding values for solid liquid extraction were 59%, 46%, 40% and 52% lower for α-solanine, α-chaconine, solanidine and demissidine respectively.

Exploring the effects of pulsed electric field processing parameters on polyacetylene extraction from carrot slices.

The effects of various pulsed electric field (PEF) parameters on the extraction of polyacetylenes from carrot slices were investigated. Optimised conditions with regard to electric field strength (1-4 kV/cm), number of pulses (100-1500), pulse frequency (10-200 Hz) and pulse width (10-30 µs) were identified using response surface methodology (RSM) to maximise the extraction of falcarinol (FaOH), falcarindiol (FaDOH) and falcarindiol-3-acetate (FaDOAc) from carrot slices. Data obtained from RSM and experiments fitted significantly (p < 0.0001) the proposed second-order response functions with high regression coefficients (R2) ranging from 0.82 to 0.75. Maximal FaOH (188%), FaDOH (164.9%) and FaDOAc (166.8%) levels relative to untreated samples were obtained from carrot slices after applying PEF treatments at 4 kV/cm with 100 number of pulses of 10 µs at 10 Hz. The predicted values from the developed quadratic polynomial equation were in close agreement with the actual experimental values with low average mean deviations (E%) ranging from 0.68% to 3.58%.

Optimization of pulsed electric field pre-treatments to enhance health-promoting glucosinolates in broccoli flowers and stalk.

BACKGROUND: The effect of pulsed electric field (PEF) treatment variables (electric field strength and treatment time) on the glucosinolate content of broccoli flowers and stalks was evaluated. Samples were subjected to electric field strengths from 1 to 4 kV cm(-1) and treatment times from 50 to 1000 µs at 5 Hz. RESULTS: Data fitted significantly (P < 0.0014) the proposed second-order response functions. The results showed that PEF combined treatment conditions of 4 kV cm(-1) for 525 and 1000 µs were optimal to maximize glucosinolate levels in broccoli flowers (ranging from 187.1 to 212.5%) and stalks (ranging from 110.6 to 203.0%) respectively. The predicted values from the developed quadratic polynomial equation were in close agreement with the actual experimental values, with low average mean deviations (E%) ranging from 0.59 to 8.80%. CONCLUSION: The use of PEF processing at moderate conditions could be a suitable method to stimulate production of broccoli with high health-promoting glucosinolate content.

Antioxidant activity guided separation of major polyphenols of marjoram (Origanum majorana L.) using flash chromatography and their identification by liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

Marjoram extracts have been separated into polar and nonpolar parts using liquid-liquid extraction. Both polar and nonpolar parts of the extracts were further fractionated by flash chromatography. The obtained fractions (90 polar and 45 nonpolar fractions) were investigated for their antioxidant activities by 2,2-diphenylpicrylhydrazyl and ferric ion reducing antioxidant power assays. A direct, positive, and linear relationship between antioxidant activity and total phenolic content of the fractions was observed. Based on antioxidant and total phenolic content data, the three fractions with the high antioxidant activities from polar and nonpolar part of the extract were analyzed for their constituent polyphenols by liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Compounds were identified by matching the mass spectral data and retention time with those of authentic standards. Identification of the compounds for which there were no "in-house" standards available was carried out by accurate mass measurement of the precursor ions and product ions generated from collision-induced dissociation. Rosmarinic acid was found to be the strongest antioxidant polyphenol conferring the highest antioxidant activity to fractions 47 and 17 of polar and nonpolar part of the extract, respectively. The identification of the rosmarinic acid was further confirmed by (1) H NMR spectroscopy.

Potential of a renin inhibitory peptide from the red seaweed Palmaria palmata as a functional food ingredient following confirmation and characterization of a hypotensive effect in spontaneously hypertensive rats.

This work examined the resistance of the renin inhibitory, tridecapeptide IRLIIVLMPILMA derived previously from a Palmaria palmata papain hydrolysate, during gastrointestinal (GI) transit. Following simulated GI digestion, breakdown products were identified using mass spectrometry analysis and the known renin and angiotensin I converting enzyme inhibitory dipeptide IR was identified. In vivo animal studies using spontaneously hypertensive rats (SHRs) were used to confirm the antihypertensive effects of both the tridecapeptide IRLIIVLMPILMA and the seaweed protein hydrolysate from which this peptide was isolated. After 24 h, the SHR group fed the P. palmata protein hydrolysate recorded a drop of 34 mm Hg in systolic blood pressure (SBP) from 187 (±0.25) to 153 (± 0.64) mm Hg SBP, while the group fed the tridecapeptide IRLIIVLMPLIMA presented a drop of 33 mm Hg in blood pressure from 187 (±0.95) to 154 (±0.94) mm Hg SBP compared to the SBP recorded at time zero. The results of this study indicate that the seaweed protein derived hydrolysate has potential for use as antihypertensive agents and that the tridecapeptide is cleaved and activated to the dipeptide IR when it travels through the GI tract. Both the hydrolysate and peptide reduced SHR blood pressure when administered orally over a 24 h period.