Relationship between the Consumption of Fermented Red Beetroot Juice and Levels of Perfluoroalkyl Substances in the Human Body's Fluids and Blood Parameters.

Per- and polyfluoroalkyl substances (PFASs) are a group of fluorinated, organic, man-made chemicals; they do not occur naturally in the environment. This study aimed to determine the profile and content of PFASs in the volunteers' blood plasma and urine after the consumption of fermented red beetroot juice and then correlated it with the blood parameters. Over 42 days, 24 healthy volunteers ingested 200 mL/60 kg of body weight of fermented red beetroot juice. PFASs were analyzed using the micro-HPLC-MS/MS method. Five perfluoroalkyl substances were found in the volunteers' body fluids. After consuming the juice, it was discovered that regarding the perfluorocarboxylic acids, a downward trend was observed, while regarding the perfluoroalkane sulfonates, and their plasma content showed a statistically significant upward trend. Analysis of the hematology parameters indicated that the intake of fermented red beetroot juice showed a significant decrease in mean corpuscular volume (MCV), platelets concentration, mean platelet volume (MPV), platelet large cell ratio (P-LCR) at the significance level p < 0.01, and hematocrit (p < 0.05). On the other hand, the dietary intervention also indicated a significant (p < 0.01) increase in corpuscular/cellular hemoglobin concentration (MCHC). In the case of blood biochemistry, no significant change was observed in the blood samples after the intake of the fermented beetroot juice. However, a decreasing tendency of total cholesterol and low-density lipoprotein concentration (LDL-C) was observed. Based on the presented results, there is a need to analyze and monitor health-promoting food regarding undesirable substances and their impact on consumer health.

Identification and Bioaccessibility of Maillard Reaction Products and Phenolic Compounds in Buckwheat Biscuits Formulated from Flour Fermented by Rhizopus oligosporus 2710.

The identification and potential bioaccessibility of phenolic compounds using the highly sensitive micro-HPLC-QTRAP/MS/MS technique and Maillard reaction products (MRPs) in buckwheat biscuits formulated from flours, raw and roasted, fermented by Rhizopus oligosporus 2710 was addressed in this study after in vitro digestion. The content of the analyzed MRPs such as furosine, FAST index, and the level of melanoidins defined by the browning index was increased in the biscuits prepared from fermented flours as compared to the control biscuits prepared from non-fermented ones. After in vitro digestion higher content of furosine was observed in control and tested biscuits providing its high potential bioaccessibility. The fermented buckwheat flours used for baking affected the nutritional value of biscuits in comparison to the control biscuits in the context of the twice-increased FAST index. More than three times higher value of the browning index was noted in control and tested biscuits after digestion in vitro indicating the high bioaccessibility of melanoidins. Our results showed the presence of ten phenolic acids and eight flavonoids in the investigated biscuits. Among phenolic acids, vanillic, syringic, and protocatechuic were predominant while in the group of flavonoids, rutin, epicatechin, and vitexin were the main compounds in analyzed biscuits. Generally, the lower potential bioaccessibility of phenolic acids and higher potential bioaccessibility of flavonoids was found for biscuits obtained from buckwheat flours fermented by fungi compared to control biscuits obtained from non-fermented flours. Fermentation of buckwheat flour with the fungus R. oligosporus 2710 seems to be a good way to obtain high-quality biscuits; however, further research on their functional properties is needed.

Bioaccessibility of Phenolic Acids and Flavonoids from Buckwheat Biscuits Prepared from Flours Fermented by Lactic Acid Bacteria.

The literature reports that the consumption of common buckwheat (Fagopyrum esculentum Moench), exactly the polyphenols it contains, is associated with a wide spectrum of health benefits. Therefore, the determination of the bioaccessibility of phenolic acids and flavonoids from buckwheat biscuits formulated from liquid-state fermented flours (BBF) by selected lactic acid bacteria (LAB) after gastrointestinal digestion was addressed in this study. Bioaccessibility could be defined as the fraction of a compound that is released from the food matrix in the gastrointestinal lumen and used for intestinal absorption. The bioaccessibility of eight phenolic acids (protocatechuic, vanillic, syringic ferulic, caffeic, sinapic, p-coumaric, and t-cinnamic) and six flavonoids (epicatechin, vitexin, orientin, apigenin, kaempferol, and luteolin) were provided for BBF and BBC (buckwheat biscuits prepared from fermented and unfermented flours, respectively). The bioaccessibility indexes (BI) indicated the high bioaccessibility of phenolic acids and improved bioaccessibility of flavonoids from BBF. Moreover, the data provide evidence for the suitability of selected LAB strains to be used as natural sour agents for further bakery product development rich in phenolic acids and flavonoids with LAB-dependent bioaccessibility.

Bioavailability of Quercetin in Humans with a Focus on Interindividual Variation.

After consumption of plant-derived foods or beverages, dietary polyphenols such as quercetin are absorbed in the small intestine and metabolized by the body, or they are subject to catabolism by the gut microbiota followed by absorption of the resulting products by the colon. The resulting compounds are bioavailable, circulate in the blood as conjugates with glucuronide, methyl, or sulfate groups attached, and they are eventually excreted in the urine. In this review, the various conjugates from different intervention studies are summarized and discussed. In addition, the substantial variation between different individuals in the measured quercetin bioavailability parameters is assessed in detail by examining published human intervention studies where sources of quercetin have been consumed in the form of food, beverages, or supplements. It is apparent that most reported studies have examined quercetin and/or metabolites in urine and plasma from a relatively small number of volunteers. Despite this limitation, it is evident that there is less interindividual variation in metabolites which are derived from absorption in the small intestine compared to catabolites derived from the action of microbiota in the colon. There is also some evidence that a high absorber of intact quercetin conjugates could be a low absorber of microbiota-catalyzed phenolics, and vice versa. From the studies reported so far, the reasons or causes of the interindividual differences are not clear, but, based on the known metabolic pathways, it is predicted that dietary history, genetic polymorphisms, and variations in gut microbiota metabolism would play significant roles. In conclusion, quercetin bioavailability is subject to substantial variation between individuals, and further work is required to establish if this contributes to interindividual differences in biological responses.

Levels of Contamination by Perfluoroalkyl Substances in Honey from Selected European Countries.

Perfluoroalkyl substances (PFASs) are man-made chemicals manufactured for numerous applications. The aim of this study was to assess the levels of 10 PFASs in selected types of honey samples from selected eastern, northern and southern European countries. A total of 26 samples of honey were analyzed. PFCAs (perfluoroalkyl carboxylic acids) were detected in almost all (92 %) analyzed samples in the range of 0.124-0.798 ng g(-1) ww (wet weight). The average concentrations of particular PFCAs (ng g(-1) ww) in honey samples increased in the following order: perfluorononanoic acid (0.164) < perfluorooctanoic acid (0.189) < perfluoroheptanoic acid (0.271) < perfluorodecanoic acid (0.278). Amongst perfluoroalkane sulfonates, only perfluorohexane sulfonate (PFHxS) was identified in four of 26 analyzed samples, and its concentrations ranged from 0.080 to 0.191 ng g(-1) ww. Italian eucalyptus honey contained the highest total content of PFASs (0.878 ng g(-1) ww). Samples originating from an industrial region of Poland showed 20 % higher concentrations of PFCAs compared to those from non-industrial regions.

Detection of Per- and Polyfluoroalkyl Substances in High-Protein Food Products.

Per- and polyfluoroalkyl substances (PFAS) belong to the emerging class of persistent organohalogenated contaminants in the environment. We determined the levels of 10 PFAS in selected samples representing different food types, with a special focus on those rich in protein such as fish, meat and meat preparations, liver, eggs, and leguminous vegetables. Such determinations were based on the Quick Easy Cheap Effective Rugged Safe extraction procedure followed by micro-high-performance liquid chromatography-tandem mass spectrometry. The most frequently found was perfluorooctanoic acid, in 84% of the food samples. However, its maximum measured concentration was 0.50 ng g-1 , in a herring sample. The highest concentrations were for perfluorobutanoic acid (35 ng g-1 measured in a pork liver sample) and perfluorooctane sulfonate (12 ng g-1 measured in a herring sample). Because these compounds may bioaccumulate in human tissues by dietary intake, further research into their impact on human health is called for. Environ Toxicol Chem 2023;42:2589-2598. © 2023 SETAC.

Bioaccessibility of Maillard Reaction Products from Biscuits Formulated from Buckwheat Flours Fermented by Selected Lactic Acid Bacteria.

The in vitro bioaccessibility of the soluble protein and Maillard reaction products (MRPs) such as furosine (an early indicator of the MR), free FIC (fluorescent intermediate compounds), and FAST index (fluorescence of advanced MRPs and tryptophan), and the level of melanoidins defined by the browning index were analyzed in biscuits formulated from raw and roasted common buckwheat flours fermented by select lactic acid bacteria (LAB). The content of soluble proteins in fermented buckwheat flour and biscuits before and after digestion in vitro was significantly dependent on the LAB applied and the type of flour used and was the highest in the digested biscuits, indicating increased bioaccessibility. Generally, in all analyzed biscuits a lower furosine content was observed as compared to control samples, and its high bioaccessibility was noted after digestion. The free FIC in biscuits was strain-dependent, resulting in low bioaccessibility with the exception of biscuits obtained from both types of flours fermented by Streptococcus thermophilus MK-10. Compared to control biscuits obtained from raw buckwheat flour, the almost twice-increased FAST index was found for samples fermented by L. plantarum IB or Streptococcus thermophilus MK-10. After digestion, at least a fivefold higher value of the browning index was noted in control and tested biscuits, indicating the high bioaccessibility of melanoidins. This study indicates that fermentation of buckwheat flours by selected lactic acid bacteria seems to be a good way to obtain a product with high bioaccessibility of MRPs. However, further research on their functional properties is needed.

An Electrochemical Determination of the Total Reducing Capacity of Wheat, Spelt, and Rye Breads.

The most interesting activities associated with bread components such as phenolic compounds, fibre, tocols, or newly formed compounds in the Maillard reaction, are their reducing properties responsible for the formation of the overall reducing capacity of bread. Among the electrochemical methods, the cyclic voltammetry (CV) technique has been recently adapted for this purpose. In this study, the application of the CV assay for the determination of the total reducing capacity of flours, doughs, and breads as well as their crumbs and crusts, originated from wheat, spelt, and rye formulated on white flours (extraction rate of 70%) and dark flours (extraction rate of 100%) and baked at 200 °C for 35 min and at 240 °C for 30 min was addressed. The reducing capacity of hydrophilic extracts from white flours and breads as well as their crumbs and crusts showed double values when compared to that of lipophilic ones whilst hydrophilic and lipophilic extracts from dark breads and their parts revealed comparable levels. The dark wheat, spelt, and rye breads showed an approximately threefold higher total reducing capacity than white breads. Baking at higher temperature slightly increased the total reducing capacity of breads and the highest value was found for dark rye bread as well as its crust baked at 240 °C for 30 min. The cyclic voltammetry methodology showed to be especially suitable for screening the bread technology and allows for obtaining rapid electrochemical profiles of bread samples.

In Vitro Expanded Bioaccessibility of Quercetin-3-Rutinoside and Quercetin Aglycone from Buckwheat Biscuits Formulated from Flours Fermented by Lactic Acid Bacteria.

The expanded bioaccessibility of rutin (Ru) and quercetin (Q) from buckwheat biscuits (BBs) formulated from liquid-state fermented flours by selected lactic acid bacteria (LAB) were determined after gastrointestinal digestion. Fermentation of buckwheat flours caused a LAB-dependent variation in Ru and Q content. BBs baked at 220 °C for 30 min showed lower content of Ru and Q, and no correlation was found between the content of these compounds in fermented flours and BBs. The expanded bioaccessibility of Ru from BBs was low when its content in the soluble and insoluble fractions remaining after digestion in vitro was taken into account. Contrary results were found for Q bioaccessibility which had an index greater than 1, indicating the high Q bioaccessibility from BBs. Since very low Q content was noted in the insoluble fraction remaining after BBs digestion, the high Q bioaccessibility was determined to be due to its concentration in the soluble fraction.

Determination of perfluoroalkyl substances (PFASs) in fats and oils by QuEChERS/micro-HPLC-MS/MS.

Per- and polyfluoroalkyl substances (PFASs) are man-made chemicals that have been identified as global pollutants. Their widespread occurrence, including in food, is a potential concern for consumers. This work focuses on the application of a simple and reliable analytical method for the simultaneous determination of ten perfluoroalkyl acids in highly complex fatty matrices (fats and oils). The perfluoroalkyl substances were extracted by the QuEChERS method, based on the dispersive-Solid Phase Extraction using styrene-divinylbenzene bulk sorbent, and quantitatively analysed by micro-high performance liquid chromatography tandem mass spectrometry. Recoveries ranged from 72 to 104% with an acceptable relative standard deviation below 10%. Limits of quantification were within the range 0.002-0.075 ng/g depending on the perfluoroalkyl compound. The most predominant compound in fat and oil food samples was perfluorooctanoic acid (PFOA) with a detection frequency of 100%, and the highest levels were found for perfluorobutanoic acid (PFBA). The estimated exposure to PFOA, which was 46% and 19% of the existing TWI for the EU and Polish population, respectively, is relatively high and indicates a potential risk to human health.

ACE Inhibitory Properties and Phenolics Profile of Fermented Flours and of Baked and Digested Biscuits from Buckwheat.

The angiotensin converting enzyme (ACE) inhibitory activity and phenolics profile of fermented flours and of baked and digested buckwheat biscuits was studied. The fermentation of buckwheat flour by select lactic acid bacteria (LAB) caused a decrease in ACE inhibitory activity as compared to the non-fermented flour. The baking process significantly reduced the ACE inhibitory activity of biscuits obtained from fermented flours, whereas digestion significantly increased these properties. In non-fermented and fermented flours and buckwheat biscuits before and after in vitro digestion samples, ten phenolic acids and eight flavonoids were found. Highly significant correlations were found between sample concentration of 50% inhibition of ACE (IC50) and total phenolic compounds of fermented flour and biscuits before and after digestion for each applied LAB, thus indicating a link between phenolic compound content and ACE inhibitory activity. In the digested biscuits, the input to ACE inhibitory activity was provided by p-coumaric, sinapic, syringic, vanillic, and protocatechuic acids as well as by kaempherol, quercetin, apigenin, and orientin. Therefore, it can be concluded that cumulative action of those phenolic acids and flavonoids released after digestion is responsible, in part, for the bioaccessible ACE inhibitory activity of buckwheat biscuits.

Quercetin from shallots (Allium cepa L. var. aggregatum) is more bioavailable than its glucosides.

The lipophilic character of quercetin suggests that it can cross enterocyte membranes via simple diffusion. Therefore, it should be more bioavailable than its glucosides, which require preliminary hydrolysis or active transport for absorption. However, the published human studies show that quercetin is less bioavailable than its glucosides. Assuming that low bioavailability of quercetin aglycone provided to humans as a pure substance is the result of its low solubility in the digestive tract, we studied its bioavailability from dietary sources in which quercetin was dispersed in the food matrix. In a randomized crossover study, 9 volunteers took a single dose of either shallot flesh (99.2% quercetin glucosides and 0.8% quercetin aglycone) or dry shallot skin (83.3% quercetin aglycone and 16.7% quercetin glucosides), providing 1.4 mg quercetin per kg of body weight. Blood samples were collected before and after consumption of shallot preparations. Plasma quercetin was measured on HPLC with electrochemical detection after plasma enzymatic treatment. The maximum plasma quercetin concentration of 1.02 +/- 0.13 micromol/L was reached at 2.33 +/- 0.50 h after shallot flesh consumption compared with 3.95 +/- 0.62 micromol/L at 2.78 +/- 0.15 h after dry skin consumption. The area under the concentration-time curve after dry skin consumption was 47.23 +/- 7.53 micromol x h(-1) x L(-1) and was significantly higher than that after shallot flesh intake (22.23 +/- 2.32 micromol x h(-1) x L(-1)). When provided along with dietary sources, quercetin aglycone is more bioavailable than its glucosides in humans. Results point to the food matrix as a key factor.

Determination of the relative contribution of quercetin and its glucosides to the antioxidant capacity of onion by cyclic voltammetry and spectrophotometric methods.

This paper describes the use of cyclic voltammetry (CV), spectrophotometric methods [Trolox equivalent antioxidant capacity (TEAC), peroxyl radical trapping capacity (PRTC), DPPH radical scavenging activity (RSA), and Folin-Ciocalteu reagent (FCR) reducing capacity], and photochemiluminescence (PCL) for the measurement of the antioxidant capacity of onion var. Sochaczewska and var. Szalotka. The antioxidant and reducing activity of the dominant onion flavonoids quercetin (Q), quercetin-3- O-beta-glucoside (Q3G), quercetin-4'- O-beta-glucoside (Q4'G), and quercetin-3,4'-di- O-beta-glucoside (Q3,4'G) were determined by spectrophotometric (TEAC and PRTC) and CV methods, respectively. The contribution of quercetin and its glucosides to the antioxidant capacity of onion was calculated in consequence of the qualitative and quantitative analysis of onion flavonoids by high-performance liquid chromatography-ultraviolet-mass spectrometry. The dominant forms of quercetin in the onion var. Sochaczewska and Szalotka included Q4'G (61 and 54%), Q3,4'G (37 and 44%), Q3G (1.4 and 1.1%), and free quercetin (1.1 and 0.7%), respectively. The CV experiment showed the highest reducing activity of Q while Q3G, Q4'G, and Q3,4'G exhibited about 68, 51, and 30% of the reducing power noted for Q. The order of the reducing activity of onion flavonoids was confirmed by their free radical scavenging activity and evaluated by TEAC and PRTC assays as follows: Q > Q3G > Q4'G > Q3,4'G. The Q4'G and Q3,4'G showed poor antioxidant activity under both applied spectrophotometric assays but still exhibited reducing activity based on CV experiments. The reducing capacity of onions determined by CV method was twice higher than the antioxidant capacity formed by water-soluble compounds (ACW) evaluated by PCL, and it was about 50% higher than PRTC and DPPH RSA results and the converted FCR reducing capacity. In contrast, the reducing capacity of onions determined by the CV method was 3-fold and about four times lower when compared to the antioxidant capacity evaluated by the TEAC method and that formed by lipid-soluble compounds (ACL) provided by PCL, respectively. The highest antioxidant capacity of onion was found under cumulative consideration of PCL (ACW + ACL) and TEAC assays. The relative contribution of Q and its glucosides to the antioxidant capacity of onions showed a low contribution of Q, Q3G, and Q3,4'G derived from CV, TEAC, and PRTC assays while the highest contribution to the antioxidant capacity of onions was provided by Q4'G.

The impact of the matrix of red beet products and interindividual variability on betacyanins bioavailability in humans.

The influence of the matrix of red beetroot products and interindividual variability on betacyanins bioavailability in humans was studied. In a randomized crossover study 12 volunteers consumed red beet juice and crunchy slices containing betanin and isobetanin. Betalains were analyzed by the HPLC-DAD-MS. Urine samples examined after the consumption of both products contained not only native betacyanins but also their aglycones. In case of juice, the highest betacyanins urine excretion rate was observed within the first 2 h (64 nmol/h), while in case of crunchy slices within the period of 2-4 h (66 nmol/h). Among volunteers, the average total betacyanins excretion rate ranged from 18.54 to 67.96 nmol/h and, 13.15 to 63.58 nmol/h for red beet juice and crunchy slices, respectively. In total, approximately 0.3% of betacyanins (ranging from 0.12 to 0.58%) ingested from both products was excreted. The study showed that betacyanins bioavailability from juice and crunchy slices is similar, with the matrix of products consumed having an impact on betacyanins excretion profile, and the phenotype of volunteers affecting betacyanins excretion rate.

The role of glucocorticoid in the regulation of prostaglandin biosynthesis in non-pregnant bovine endometrium.

To determine whether glucocorticoids (GCs) play a role in regulating uterine function in cow, the present study examined the expression of mRNA encoding GC receptor (GC-R) alpha, 11beta-hydroxysteroid dehydrogenase (11-HSD) type 1 and type 2, and the activity of 11-HSD1 in bovine endometrial tissue throughout the estrous cycle. We also studied the effects of cortisol on basal, oxytocin (OT)- and tumor necrosis factor-alpha (TNFalpha)-stimulated prostaglandin (PG) production. A quantitative real-time PCR analysis revealed that GC-Ralpha mRNA was expressed more strongly in the mid-luteal stage (days 8-12) than in the other stages. In contrast to GC-Ralpha mRNA expression, 11-HSD1 mRNA expression was greater in the follicular stage than in the other stages, whereas 11-HSD2 mRNA expression was lowest in the follicular stage. The activity of 11-HSD1 was greater in the follicular stage and estrus than in the other stages and was lowest in the mid-luteal stage. Cortisone was dose-dependently converted to cortisol in the cultured endometrial tissue. Although cortisol did not affect either the basal or OT-stimulated production of PGs in the cultured epithelial cells, the production of PGs stimulated by TNFalpha in the stromal cells was suppressed by cortisol (P < 0.05). Cortisol suppressed basal prostaglandin (PG)F2alpha without affecting basal PGE2 production in the stromal cells. The overall results suggest that the level of cortisol is locally regulated in bovine endometrium throughout the estrous cycle by 11-HSD1, and that cortisol could act as a luteoprotective factor by selectively suppressing luteolytic PGF2alpha production in bovine endometrium.

Antioxidant contents and antioxidative properties of traditional rye breads.

The purpose of this research was to find out the effect of flour extraction rate on the antioxidative properties of traditional rye bread and then to compare the bioactive compounds content and antioxidant properties of rye breads with commercial wheat roll. Four types of rye flour with different extraction rates of 100 (whole meal dark flour), 95 (brown flour), 90 (brown flour), and 70% (light flour) originated from Warko rye cultivar were used for traditional bread baking with sourdough fermentation. Four types of the respective rye breads were analyzed for their potentially beneficial components, including tocopherols and tocotrienols, total phenolics and flavonoids, reduced glutathione, and inositol hexaphosphates. Moreover, the phenolic acids profile was provided. The Trolox equivalent antioxidant capacity (TEAC) of the breads was evaluated using free radical scavenging activities of 80% methanol extracts against ABTS*+ radical cation (ABTS radical cation decolorization method) whereas radical scavenging activity (RSA) was determined against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*). The superoxide dismutase-like activity (SOD-like activity) was evaluated as free radical scavenging activities of PBS extracts against superoxide anion radicals (O2*-). The results were compared to whole meal rye bread as well as to wheat roll taken as representative example of wheat based bakery product. The studies showed that flour extraction rates strongly affected the content of bioactive compounds and antioxidative properties of traditionally baked rye breads. The incorporation of the rye flours with extraction rates from 100 down to 70% in the formulation caused decrease in tocopherol (T), tocotrienol (T3), inositol hexaphosphate (IP6), and phenolic compound (TPC) contents in rye breads. No changes in reduced glutathione (GSH) contents were noted between each type of rye bread. A significant decrease in Trolox equivalent antioxidant capacity and radical DDPH scavenging activity was also found in bread formulated on flour with an extraction rate of 70% in comparison to the breads formulated on flour with extraction rates from 100 to 90%. The highest SOD-like activity was noted for rye bread formulated on flour with an extraction rate of 70%. The four types of rye breads showed better antioxidative properties and higher antioxidant contents when compared to wheat roll with one exception made to tocopherols and tocotrienols.

Fermentation as a bio-process to obtain functional soybean flours.

The effect of fermentation on the antioxidant compounds [vitamins C and E, total phenolic compounds (TPC), and reduced glutathione (GSH)], and antioxidant capacity [superoxide anion scavenging activity (SOD-like activity), peroxyl radical-trapping capacity (PRTC), inhibition of phosphatidylcholine (PC) peroxidation, and Trolox equivalent antioxidant capacity (TEAC)] of soybean (Glycine max cv. Merit) was studied. Fermentation was carried out in solid state in cracked seeds inoculated with Aspergillus oryzae, Rhizopus oryzae, Bacillus subtilis, and Lactobacillus plantarum and in liquid state either in cracked seeds or milled soybean flours fermented naturally by only the microorganisms present in the seeds or by inoculation with L. plantarum. Vitamin C was not detected in the studied samples. Fermentation caused a decrease in vitamin E activity, except when cracked seed was fermented with A. oryzae, R. oryzae, or B. subtilis that increased 31, 30, and 89%, respectively. Fermentation produced an increase in TPC content and did not affect or reduce the GSH content. Fermentation decreased SOD-like activity drastically, while PRTC increased except when it was carried out naturally in cracked seed. TEAC values rose sharply when soybeans were fermented with B. subtilis. Processed soybean extracts inhibited PC peroxidation in comparison with the control assay. On the basis of the results obtained, the relative contributions of vitamin E, TPC, and GSH to antioxidant capacity were calculated and results showed a very high TPC contribution and a low contribution of GSH and vitamin E activity. Optimum results for functional soybean flours were achieved when fermentation was carried out with B. subtilis inoculum.

Buckwheat bioactive compounds, their derived phenolic metabolites and their health benefits.

SCOPE: Buckwheat (BW) consumption has been associated with a broad range of health benefits: antioxidant, anti-inflammatory and anticancer. These beneficial effects have been partially related to the presence of flavonoids. However, some of these compounds (i.e., rutin and quercetin) are metabolized in the gastrointestinal tract generating derived phenolic metabolites. In this study, we investigated the biological activity of rutin (Ru), quercetin (Q) an their derived phenolic metabolites 3,4-dihydroxyphenylacetic acid (3,4-DHPAA), 3-hydroxyphenylacetic acid (3-HPAA), and 4-hydroxy-3-methoxyphenylacetic acid (homovanillic acid, HVA). METHODS AND RESULTS: Q showed the highest antioxidant and reducing activity, and Ru the maximum chelating activity (85.33%). Antioxidant activity of 3,4-DHPAA was 5-fold higher than that of HVA, whereas their reducing activity was similar. The formation of methylglyoxal (MGO)-BSA and glucose-BSA (advanced glycation end products) was inhibited by Ru (98.5 and 92.7%), Q (95.6 and 89.1%) and 3,4-DHPPA (84.4.6 and 77.5%). Furthermore, Q (10-50 µM) and Ru (1-50 µM) downregulated the release of PGE2 , IL-8 and MCP-1, molecules involved in the inflammatory response, in IL1ß-inflamed myofibroblasts of colon CCD-18Co. CONCLUSION: This study suggests that BW phytochemicals and their phenolic metabolites may be responsible for the beneficial effects against chronic diseases attributed to BW consumption.

Development, validation and evaluation of an analytical method for the determination of monomeric and oligomeric procyanidins in apple extracts.

There is a lack of data for individual oligomeric procyanidins in apples and apple extracts. Our aim was to develop, validate and evaluate an analytical method for the separation, identification and quantification of monomeric and oligomeric flavanols in apple extracts. To achieve this, we prepared two types of flavanol extracts from freeze-dried apples; one was an epicatechin-rich extract containing ∼30% (w/w) monomeric (-)-epicatechin which also contained oligomeric procyanidins (Extract A), the second was an oligomeric procyanidin-rich extract depleted of epicatechin (Extract B). The parameters considered for method optimisation were HPLC columns and conditions, sample heating, mass of extract and dilution volumes. The performance characteristics considered for method validation included standard linearity, method sensitivity, precision and trueness. Eight laboratories participated in the method evaluation. Chromatographic separation of the analytes was best achieved utilizing a Hilic column with a binary mobile phase consisting of acidic acetonitrile and acidic aqueous methanol. The final method showed linearity for epicatechin in the range 5-100µg/mL with a correlation co-efficient >0.999. Intra-day and inter-day precision of the analytes ranged from 2 to 6% and 2 to 13% respectively. Up to dp3, trueness of the method was >95% but decreased with increasing dp. Within laboratory precision showed RSD values <5 and 10% for monomers and oligomers, respectively. Between laboratory precision was 4 and 15% (Extract A) and 7 and 30% (Extract B) for monomers and oligomers, respectively. An analytical method for the separation, identification and quantification of procyanidins in an apple extract was developed, validated and assessed. The results of the inter-laboratory evaluation indicate that the method is reliable and reproducible.

Antioxidants in thermally treated buckwheat groats.

The seeds of buckwheat (Fagopyrum esculentum Moench L.) were dehulled and then, following milling, extruded on a counter rotating, twin-screw extruder with the different barrel temperature profiles: 120, 160, and 200 degrees C. After extrusion cooking process, the following compounds were analyzed: free and conjugated phenolic acids, total polyphenols (TPC), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP), reduced glutathione (GSH), and melatonin (MLT). The antioxidant capacity and superoxide dismutase-like activity (SOD-like activity) were determined in the groats and extrudates. Extrusion caused a significant decrease in all the compounds tested, except for phenolic acids. The content of IP decreased by 13%, that of GSH by 42%, and that of T + T3 by 62%. A three-fold lower level of MLT and TPC was noted whereas the SOD-like activity disappeared when compared to the nonextruded material. A two-fold higher content of phenolic acids (free and released from ester bonds) was observed. In spite of the clear decrease in the investigated antioxidants, the extruded dehulled buckwheat seeds contained still significant content of bioactive compounds, which resulted in as little as an average 10% decrease of the antioxidant capacity.