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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Effect of roasting time of buckwheat groats on the formation of Maillard reaction products and antioxidant capacity.

Changes in the formation of Maillard reaction products and antioxidant capacity of buckwheat, induced by roasting at 160 °C for 30, 40 and 50 min, were evaluated in the study. Furozine, was detected after roasting, in all buckwheat samples. Increase of FIC, the presence of significant amounts of CML and enhanced browning were observed, along with increasing times of roasting. The formation of acrylamide in the obtained buckwheat products was also significantly connected with the time of roasting. A significant degradation was observed in natural antioxidants, as affected by heat treatment time. The colour parameter changed significantly with the increasing of roasting time. Overall, 30min of roasting was beneficial from a nutritional point of view for the obtained buckwheat product.

Quercetin and isorhamnetin aglycones are the main metabolites of dietary quercetin in cerebrospinal fluid.

SCOPE: Reports on the protective effect of certain foods on brain functions are numerous; however, the permeability of the brain barriers by food components is still hardly recognised. There have been in vitro studies aimed at demonstrating this possibility, but not much is known about this phenomenon in in vivo systems. The objective of the study was to determine the metabolites of dietary quercetin (Q) in urine, blood plasma and cerebrospinal fluid (CSF) after intra-rumen administration of Q rich onion dry skin in an animal model. METHODS AND RESULTS: Eleven sheep had permanently implanted cannulas in the third ventricle of the brain as the means for CSF collection. The animals were administered Q at the dose of 10 mg/kg bwt. For 12 h the concentration of Q metabolites was measured in urine, blood plasma, and CSF. It was demonstrated that while in blood plasma Q and isorhamnetin mono-glucuronides or mono-sulphates were the main metabolites (80%), in CSF their aglycones were the dominating ones (88%). CONCLUSION: Q and IR aglycones are the main Q metabolites present in CSF after dietary Q intake. Their passive transport through blood-CSF barrier or a de-conjugating mechanism within that barrier may be involved.

Exposure of breastfed infants to quercetin after consumption of a single meal rich in quercetin by their mothers.

SCOPE: The exposure to quercetin (Q) has not been studied in breastfed infants whose mothers were consuming a Q-rich diet. The objective of the study was to determine whether plant-origin antioxidant-Q passes from the mother's diet to her milk and to calculate the pharmacokinetic parameters of this phenomenon. METHODS AND RESULTS: Eleven breastfeeding women were included in this controlled case study. Volunteers followed a Q-restricted diet for 5 consecutive days with the exception of the 3rd day when they received a single meal providing 1 mg of Q per kg of body weight. Urine analysis showed the presence of Q already in the first collected samples after the test (1.5-4 h), which indicated its rapid absorption from the meal. The Cmax = 68 ± 8.44 nmol/L concentration of Q in the milk was calculated for Tmax = 11.89 ± 3.37 h. It was significantly different (p = 0.007) from 40 nmol/L and (p = 0.016) from 42 nmol/L of Q concentration before and 48 h after the test, respectively. CONCLUSIONS: Q was shown to be a component of human milk at the nmol/L level. Infants breastfed by mothers consuming a diet rich in Q are exposed to a dose of approximately 0.01 mg of Q daily.

Accumulation of orally administered quercetin in brain tissue and its antioxidative effects in rats.

Quercetin is widely distributed in vegetables and herbs and has been suggested to act as a neuroprotective agent. Here, we demonstrate that quercetin can accumulate enough to exert biological activity in rat brain tissues. Homogenates of perfused rat brain without detectable hemoglobin contaminants were treated with ß-glucuronidase/sulfatase and the released quercetin and its methylated form were analyzed using high-performance liquid chromatography (HPLC) with three different detection methods. Both quercetin and the methylated form were detected in the brain of quercetin-administered rats using HPLC-UV and HPLC with electrochemical detection and were further identified using HPLC-tandem mass spectrometry. Oral administration of quercetin (50mg/kg body wt) attenuated the increased oxidative stress in the hippocampus and striatum of rats exposed to chronic forced swimming. The possible transport of quercetin derivatives into the brain tissue was reproduced in vitro by using a rat brain capillary endothelial cell line, a model of the blood-brain barrier. These results show that quercetin could be a potent nutrient that can access the brain and protect it from disorders associated with oxidative stress.

Bioavailability of cyanidin glycosides from natural chokeberry (Aronia melanocarpa) juice with dietary-relevant dose of anthocyanins in humans.

The aim of this study was to investigate the bioavailability of anthocyanins from chokeberry juice with a dietary-relevant dose of anthocyanins. Thirteen healthy volunteers consumed chokeberry juice providing 0.8 mg of anthocyanins/kg of body weight. Before and after juice consumption, blood and urine were collected. Concentration of anthocyanins was measured with HPLC-PDA-MS-ESI. Cyanidin-3-galactoside comprised 66% of total chokeberry anthocyanins. Eight cyanidin derivatives were found in blood and urine after juice consumption. The maximum plasma anthocyanin concentration of 32.7 ± 2.9 nmol/L was reached at 1.3 ± 0.1 h after juice consumption. The anthocyanins' urine excretion rate (62.9 ± 5.0 nmol/h) was the highest within the first 2 h. In total, 0.25 ± 0.02% of the ingested anthocyanins was excreted by the renal route during 24 h, mainly as metabolites of cyanidin. According to these observations, after consumption of a dietary-relevant dose of anthocyanins as natural chokeberry juice, anthocyanins and their metabolites were present in plasma and urine of volunteers.