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Dipicolinic acid (DPA) is a major constituent of spores and reportedly provides protection against inactivation by various thermal processes; however, the relationship between DPA and resistance towards pressure-assisted thermal processing is not well understood. Thermal and pressure-assisted thermal inactivation studies of Clostridium botulinum nonproteolytic strains QC-B and 610-F, proteolytic strain Giorgio-A, and thermal surrogate Clostridium sporogenes PA3679 spores suspended in ACES buffer (0.05 M, pH 7.0) were performed to determine if a relationship exists between DPA release and log reduction of spores. Thermal inactivation at 80, 83, and 87 °C for nonproteolytic strains and 101, 105, and 108 °C for the proteolytic strain and thermal surrogate were conducted. Pressure-assisted thermal inactivation for nonproteolytic strains at 83 °C/600 MPa and for the proteolytic strain and thermal surrogate at 105 °C/600 MPa were performed. Surviving spores were enumerated by 5-tube MPN method for log reductions and analyzed for released DPA by liquid chromatography-tandem mass spectrometry. The correlation between MPN log reductions, released DPA, and D-values were calculated. A positive correlation between released DPA and log reduction of spores was observed for QC-B and 610-F at 80 and 83 °C (r = 0.6073 - 0.7755; P < 0.01). At 87 °C, a positive correlation was detected for 610-F (r = 0.4242, P < 0.05) and no correlation was observed for QC-B (r = 0.1641; P > 0.05). A strong, positive correlation (r = 0.8359 - 0.9284; P < 0.05) between released DPA and log reduction of spores was observed for Giorgio-A at 101, 105, and 108 °C, and a strong, positive correlation (r = 0.8402; P < 0.05) was observed for PA3679 at 101 °C. A positive correlation (r = 0.5646 - 0.6724; P < 0.01) was observed for QC-B, 610-F, and Giorgio-A after pressure-assisted thermal treatment. No correlation (r = 02494; P > 0.05) was found for PA3679 after pressure-assisted thermal treatment. These results suggest a correlation exists between DPA release and heat resistance; however, the level of correlation varied between strains and temperatures. The findings from this research may aid in the development of spore inactivation strategies targeting the thermal resistance profiles of various strains of C. botulinum spores., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Inc.)

The effect of thermal processing treatments on key micronutrients in fortified almond-based beverages has not been well characterized. An almond-based beverage was produced in a pilot plant, fortified with vitamin A palmitate, vitamin D2, riboflavin (vitamin B2), calcium carbonate, and zinc gluconate, and was processed using various high-temperature short-time (HTST) pasteurization treatments. Naturally present micronutrients in the base ingredients included several B vitamins (vitamin B1 [thiamin], total vitamin B3 [sum of nicotinamide and nicotinic acid], and total vitamin B6 [sum of pyridoxal, pyridoxamine, and pyridoxine]) and minerals (magnesium, phosphorus, and potassium). The prepared almond-based beverage was homogenized and thermally processed using HTST pasteurization with a temperature range from ~94 to 116°C for a constant time of 30 s. The samples were analyzed for vitamin A palmitate, vitamin D2, target B vitamins (thiamin, riboflavin, total vitamin B3, and total vitamin B6), and minerals (magnesium, phosphorus, potassium, calcium, and zinc). The results showed that amounts of vitamin A, vitamin D2, riboflavin, and total vitamin B6 did not significantly ( p > 0.05) change after the HTST treatments, whereas thiamin significantly ( p < 0.05) decreased by 17.9% after HTST treatment at 116°C. Interestingly, total vitamin B3 content significantly ( p < 0.05) increased by 35.2% after HTST treatment at 116°C. There was no effect of processing on the minerals that were monitored. The results from this study indicate that the majority of key micronutrients assessed in this study are stable during HTST processing of an almond-based beverage and that fortification of plant-based milk alternatives may be a viable process to enhance the micronutrient content consumers receive from these products., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Redan, Zuklic, Cai, Warren, Carter, Wan, Sandhu, Black and Jackson.)

For centuries, Hawaiians have gathered seaweed for food, medicine, and ceremonial purposes. Seaweed contains nutrients, but some varieties can accumulate toxic elements. We measured target macrominerals (Na, Mg, P, K, Ca), microminerals (B, V, Mn, Co, Cu, Zn, Mo), and nonessential/toxic elements (As, Sr, Cd, Sn, Hg, Pb, and U) in a sample of wild-collected and cultivated seaweeds from Hawai'i. The samples consisted of brown (Sargassum aquifolium, Sargassum echinocarpum), red (Gracilaria parvispora, Halymenia formosa, Halymenia hawaiiana), and green (Ulva ohnoi) seaweed. Elemental composition was determined by inductively coupled plasma (ICP)-atomic emission spectroscopy and ICP-mass spectrometry (MS). Speciation of As was conducted by using liquid chromatography-ICP-MS. S. echinocarpum per 80 g serving was high in Ca (~37% daily value [DV]), U. ohnoi was high in Mg (~40%DV), H. formosa was high in Fe (~40%DV), and G. parvispora was high in Mn (~128%DV). In this study, the highest amounts of toxic elements were observed in S. aquifolium and S. echinocarpum (27.6 mg inorganic As/kg fdw), G. parvispora (43.3 mg Pb/kg fdw) and H. formosa (46.6 mg Pb/kg fdw). These results indicate that although seaweeds from Hawai'i contain a variety of nutrients, some species can accumulate high amounts of toxic elements.

A wide variety of commercial plant-based foods that are marketed and sold as alternatives for milk (plant-based milk alternatives or PBMAs) are available to consumers. In this study, PBMAs from the United States (n=85) were subjected to analysis for target minerals (magnesium, phosphorus, selenium, and zinc) to compare their variability across PBMA types, brands, and production lots. Samples were also screened for the environmental contaminant elements arsenic, cadmium, and lead. The eight PBMA types sampled were produced from almond, cashew, coconut, hemp, oat, pea, rice, and soy. Elemental analysis was conducted using microwave-assisted acid digestion followed by inductively coupled plasma-mass spectrometry. The results showed that pea PBMAs contained the highest mean amounts of phosphorus, selenium, and zinc, while soy PBMAs were highest in magnesium. Mean amounts of minerals were lower than those found in milk for the majority of PBMA types. There was significant variation ( P <0.05) in amounts of minerals across the majority of product brands. The amounts of phosphorus and magnesium varied across production lots ( P <0.05), but the absolute value of these differences was low. Total arsenic was highest in rice PBMAs; amounts of cadmium and lead across PBMAs were generally found at low or non-quantifiable amounts. These results underscore the importance of generating analytical data on the elemental composition of products within the rapidly growing category of PBMA.

Aims: Viral diseases can be indirectly transmitted by contaminated non-food contact surfaces to final food products by cross-contamination. The interaction of metal surfaces and viruses, MS2 coliphage and hepatitis A virus (HAV), was investigated for strategy development in decreasing this transmission risk., Methods and Results: MS2 deposited onto stainless-steel surface was stable but inactivated at 0.95 log10 PFU min-1 on 99.9% copper surfaces. Greater copper-inactivation of MS2 was observed in (a) simple media (phosphate buffered saline, PBS) than protein-rich media (beef extract buffer), and (b) acidic than pH ≥ 6.8 environments. Among food matrices (strawberry juices and beef broth), the greatest MS2 inactivation by copper occurred in filtered strawberry juice at pH 3.5. At a reduction of 0.17 log10 PFU min-1, HAV survived longer than MS2 on copper by FRhK-4 cell infectivity assay., Conclusions: The inactivation of virus on copper surfaces was greater in acidic viral surrounding environments and in simple PBS medium. In the same 99% PBS medium, MS2 may not be an appropriate surrogate for HAV when assessing viral inactivation on copper surfaces., (Published by Oxford University Press on behalf of Applied Microbiology International 2023. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

We performed a market basket survey of plant-based milk alternatives (PBMAs) from the US market for vitamin A, vitamin D, calcium, and potassium to identify the amount and variability of these micronutrients across various PBMAs. The PBMA types included in this analysis were almond, cashew, coconut, hemp, oat, pea, rice, and soy (n=90 total product units). Analyses for vitamin A (as retinyl palmitate), vitamin D2/D3, and minerals were performed using high-performance liquid chromatography, liquid chromatography-tandem mass spectrometry, and inductively coupled plasma-mass spectrometry, respectively. A majority of PBMA types had significant differences ( P <0.05) in the amounts of target micronutrients across brands. The coefficient of variation (%CV) for micronutrient concentrations within one lot of a single brand ranged from 4.1-42.2% for vitamin A, 1.5-44.1% for vitamin D, 1.7%-37.6% for calcium, and 0.7%-39.0% for potassium. The variability of these micronutrients should be taken into account when considering the nutritional value of PBMAs., Competing Interests: Declaration of interest The authors have no competing interests.

Analysis of the dipicolinic acid (DPA) released from Clostridium botulinum spores during thermal processing is crucial to obtaining a mechanistic understanding of the factors involved in spore heat resistance and related food safety applications. Here, we developed a novel mixed-mode liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection of the DPA released from C. botulinum type A, nonproteolytic types B and F strains, and nonpathogenic surrogate Clostridium sporogenes PA3679 spores. DPA was retained on a mixed-mode C18/anion exchange column and was detected using electrospray ionization (ESI) positive mode within a 4-min analysis time. The intraday and interday precision (%CV) was 1.94-3.46% and 4.04-8.28%, respectively. Matrix effects were minimal across proteolytic type A Giorgio-A, nonproteolytic types QC-B and 202-F, and C. sporogenes PA3679 spore suspensions (90.1-114% of spiked DPA concentrations). DPA recovery in carrot juice and beef broth ranged from 105 to 118%, indicating limited matrix effects of these food products. Experiments that assessed the DPA released from Giorgio-A spores over the course of a 5-min thermal treatment at 108 °C found a significant correlation (R = 0.907; P < 0.05) between the log reduction of spores and amount of DPA released. This mixed-mode LC-MS/MS method provides a means for rapid detection of DPA released from C. botulinum spores during thermal processing and has the potential to be used for experiments in the field of food safety that assess the thermal resistance characteristics of various C. botulinum spore types., (© 2022. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Limited information is available on methods to reduce concentrations of the opium alkaloid noscapine in poppy seeds. A series of experiment were conducted using poppy seeds to evaluate the impact of thermal treatments, water rinsing, and baking on noscapine concentrations. A sample set of commercially available poppy seeds (n=15) was screened for noscapine using liquid chromatography-tandem mass spectrometry. The mean and median noscapine concentrations for poppy seed samples above the limit of quantitation (LOQ) was 89.9 and 28.4 mg kg -1 , respectively. Six out of 15 samples were less than the LOQ. Poppy seed samples containing a mean noscapine concentration of 121 mg kg -1 were subjected to dry heat treatments ranging from 120-200 °C and a 5 min rinse with water. Baking experiments were also done by incorporating the poppy seeds into a muffin batter and baking in an oven at 200 °C. The dry heat treatment experiments showed that noscapine degraded at 160-200 °C, with a 50% loss of noscapine observed after 3.44 ± 0.46 min at 200 °C. Although the mean concentration of noscapine decreased when a muffin containing poppy seeds was baked at 200 °C for 16 min, these changes were not statistically significant ( P >0.05). Rinsing the poppy seeds with water did not have a significant effect on noscapine concentrations. Together, these data allow for better characterization of potential dietary exposure to noscapine and indicate that certain thermal treatments can be effective for reduction of noscapine in poppy seeds.

Edible algae products have increasingly become a larger component of diets worldwide. Algae can be a source of essential micronutrients and bioactive phytochemicals, although select varieties also often contain elevated concentrations of heavy metal contaminants. Due to the effects thermal processing of foodstuffs can have on levels of nutrients, phytochemicals, and contaminants, it is important to consider the role processing has on the levels of these components in algae food products. Here, we evaluate the literature covering how different types of processing, including commercial thermal application and in-home preparation, affect constituents such as vitamins, minerals, carotenoids, pigment compounds, and metal contaminants. Overall, the literature suggests that there are optimum processing conditions and specific cooking techniques that can be used to increase retention of important nutritional components while also reducing concentrations of metal contaminants. Although further research is needed on how thermal processing affects individual compounds in algae and their ultimate bioavailability, these data should be taken into consideration in order to inform design of product processing to both increase retention of nutritional components and limit metal contaminants.

Abstract: Ethyl carbamate (EC) is a process contaminant that can be formed as a by-product during fermentation and processing of foods and beverages. Elevated EC concentrations are primarily associated with distilled spirits, but this compound has also been found at lower concentrations in foods and beverages, including breads, soy sauce, and wine. Evidence from animal studies suggests that EC is a probable human carcinogen. Consequently, several governmental institutions have established allowable limits for EC in the food supply. This review includes EC formation mechanisms, occurrence of EC in the food supply, and EC dietary exposure assessments. Current analytical methods used to detect EC will be covered, in addition to emerging technologies, such as nanosensors and surface-enhanced Raman spectroscopy. Various mitigation methods have been used to maintain EC concentrations below allowable limits, including distillation, enzymatic treatments, and genetic engineering of yeast. More research in this field is needed to refine mitigation strategies and develop methods to rapidly detect EC in the food supply., (Published 2021 by the International Association for Food Protection. Not subject to U.S. Copyright.)

Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Nanotechnology-based packaging may improve food quality and safety, but packages manufactured with polymer nanocomposites (PNCs) could be a source of human dietary exposure to engineered nanomaterials (ENMs). Previous studies showed that PNCs release ENMs to foods predominantly in a dissolved state, but most of this work used food simulants like dilute acetic acid and water, leaving questions about how substances in real foods may influence exposure. Here, we demonstrate that food and beverage ingredients with reducing properties, like sweeteners, may alter exposure by inducing nanoparticle formation in foods contacting silver nanotechnology-enabled packaging. We incorporated 12.8 ± 1.4 nm silver nanoparticles (AgNPs) into polyethylene and stored media containing reducing ingredients in packages manufactured from this material under accelerated room-temperature and refrigerated conditions. Analysis of the leachates revealed that reducing ingredients increased the total silver transferred to foods contacting PNC packaging (by as much as 7-fold) and also induced the (re)formation of AgNPs from this dissolved silver during storage. AgNP formation was also observed when Ag + was introduced to solutions of natural and artificial sweeteners (glucose, sucrose, aspartame), commercial beverages (soft drinks, juices, milk), and liquid foods (yogurt, starch slurry), and the amount and morphology of reformed AgNPs depended on the ingredient formulation, silver concentration, storage conditions, and light exposure. These results imply that food and beverage ingredients may influence dietary exposure to nanoparticles when PNCs are used in packaging applications, and the practice of using food simulants may in certain cases underpredict the amount of ENMs likely to be found in foods stored in these materials.

There are currently increased efforts to determine potential sources of trace metal contaminants in the food supply. While there are likely many sources of these elements, processing of foods has gained attention as one such route. Research is reviewed on how processing aids used for food production, including beverage filtration and fining, have been targeted as potential sources of trace metals. Potential remediation methods to reduce elemental transfer occurring during processing is discussed. While food processing aids are often a critical part of food manufacturing, they can be a potential source of trace metal contaminants, including heavy metals.

A symposium was held at the 2019 American Chemical Society (ACS) Fall National Meeting in San Diego, CA, U.S.A., entitled "Metals Trace Elements in Food Safety, Health, and Food Quality". The 2 day symposium was sponsored by the Division of Agricultural and Food Chemistry (AGFD) and co-sponsored by the Division of Agrochemicals (AGRO). This symposium was convened to broadly cover advances in the detection of metals/trace elements in food and our understanding of how metals and trace elements impact food safety, food quality, toxicology, and human nutrition. There were 21 presentations from speakers from academia, government, and industry. This introduction provides a brief summary of the presentations and serves as a record of the symposium proceedings.

Limited information exists on the effectiveness of potential treatments to reduce levels of opium alkaloids that may be present in seeds from poppy ( Papaver somniferum L.). Poppy seeds containing morphine at relatively lower (14.7 mg kg -1 ) and higher (210.0 mg kg -1 ) concentrations were subjected to dry heat and steam treatments, water washing, and baking. Sample extracts were then analyzed using liquid chromatography-tandem mass spectrometry for the opium alkaloids morphine, codeine, and thebaine. The results indicated that thermal treatment promoted opium alkaloid degradation in poppy seed samples, with a 50% loss of morphine observed after 30-40 min at 200 °C. Water washing reduced concentrations of opium alkaloids in poppy seeds by approximately 50-80%, while steam treatment resulted in reduction of morphine in only one sample type. Importantly, baking had no significant effect on concentrations of opium alkaloids. Overall, these results indicate that opium alkaloids may not be significantly affected by baking or steam application and that poppy seeds may require water washing or extended thermal treatment to promote reduction of these compounds.

Copper (Cu) metal and alloys are used in cookware and other food contact surfaces due to their desirable properties for various applications. However, Cu metal can ionise and subsequently transfer to food and beverages under certain conditions. Here, we tested how pH and temperature affected Cu release kinetics using model systems utilising Cu metal foil and commercially available copperware. Cu foil and copperware were exposed to food simulants composed of 3% (w:w) aqueous solutions of citric acid, malic acid, acetic acid, or deionised (DI) water at temperatures ranging from 4°C to 60°C. An additional pilot experiment tested how simulated long-term cleaning affected subsequent Cu release from lined and unlined copperware to 3% citric acid. Food simulants were then analysed by ICP-MS for total Cu. After 180 min, incubation of Cu metal foil with acid-containing food simulants at 4°C resulted in Cu release ranging from 8.7 - 14.0 µg cm -2 , while 21.5-38.1 µg cm -2 was released at 60°C. In contrast, Cu transfer from metal foil to DI water was relatively low, with <0.6 µg cm -2 released after 180 min at 60°C. With citric acid food simulant, lined copperware released between 0.6 and 3.0 µg Cu cm -2 over 180 min at the set temperatures, while unlined copperware released approximately 25-45 fold higher amounts of Cu (26.9-74.6 µg cm -2 ) over this same time period. In contrast, use of DI water food simulant resulted in Cu release of <0.1 µg cm -2 for the lined copperware and <2 µg cm -2 for the unlined type. No significant effect of simulated long-term cleaning on Cu release from copperware was observed. These data indicate that Cu release is affected by temperature and pH, and that specific steps can be taken to limit Cu metal release from food contact surfaces to foods and beverages.

Anthocyanins and the broader class of polyphenols are strong antioxidants in vitro. Polyphenols are one of the major antioxidants in plant foods, and the beverages derived from them. There is extensive evidence in the literature that polyphenols are beneficial to health. In order to be bioactive in vivo, they need to be bioavailable and be transported from the circulation to target organs. To date, there have been few studies testing the extent to which polyphenols and especially anthocyanins affect the antioxidant capacity of animal organs. In our first pilot study, we investigated how three pure polyphenols (the flavonoids quercetin, catechin and hesperetin) given to rats by intraperitoneal injection (49 to 63 mg/kg) affected their organ antioxidant capacity. This was followed by a subsequent study that injected one ml of 100% cranberry juice (high in anthocyanins) to hamsters. Antioxidant capacity of animal organs was determined by using the ferric reducing antioxidant power (FRAP) colorimetric assay on methanolic extracts of select rat organs (i.e., liver, kidney, heart, prostate and brain) and in the hamster organs (i.e., liver, kidney, heart, bladder and brain). Overall the results showed that antioxidant capacity was significantly increased ( p < 0.05) in experimental vs. control organs. Analysis of organs by high performance liquid chromatography (HPLC) from both animal studies provided evidence of polyphenol metabolites in the organ extracts. Taken together, this study provides data that the administration of anthocyanins and other polyphenols cause an increase in organ antioxidant capacity in two animal models. This result supports the growing evidence for the hypothesis that dietary polyphenols reduce the risk and extent of various chronic disease at the disease site.

Filtration methods for alcoholic fermented beverages often use filter aids such as diatomaceous earth (DE), which may contain elevated amounts of the heavy metals arsenic (As), lead (Pb), and cadmium (Cd). Here, we evaluated factors affecting transfer of these heavy metals from DE to beer and wine. A laboratory-scale filtration system was used to process unfiltered ale, lager, red wine, and white wine with three types of food-grade DE. Filtrate and DE were analyzed for heavy metals using ICP-MS, in addition to LC-ICP-MS for As-speciation analysis. Use of 2 g/L DE containing 5.4 mg/kg soluble inorganic As (iAs) for filtering beer and wine resulted in significant ( p < 0.05) increases of 11.2-13.7 μg/L iAs in the filtered beverage. There was a significant ( p < 0.05) effect from the DE quantity used in filtration on the transfer of iAs in all beverage types, whereas no alterations were observed for Pb and Cd levels. Methods to wash DE using water, citric acid, or EDTA all significantly ( p < 0.05) reduced iAs concentrations, whereas only EDTA significantly reduced Pb levels. Cd concentrations were not affected by any wash method. These data indicate that specific steps can be taken to limit heavy-metal transfer from DE filter aids to beer and wine.

Berries and other anthocyanin-rich treatments have prevented weight gain and adiposity in rodent models of diet-induced obesity. Their efficacy may be explained by modulation of energy substrate utilization. However, this effect has never been translated to humans. The objective of this study was to evaluate the effects of berry intake on energy substrate use and glucoregulation in volunteers consuming a high-fat diet. Twenty-seven overweight or obese men were enrolled in a randomized, placebo-controlled crossover study with two treatment periods. Subjects were fed an investigator controlled, high-fat (40% of energy from fat) diet which contained either 600 g/day blackberries (BB, 1500 mg/day flavonoids) or a calorie and carbohydrate matched amount of gelatin (GEL, flavonoid-free control) for seven days prior to a meal-based glucose tolerance test (MTT) in combination with a 24 h stay in a room-sized indirect calorimeter. The washout period that separated the treatment periods was also seven days. The BB treatment resulted in a significant reduction in average 24 h respiratory quotient (RQ) (0.810 vs. 0.817, BB vs. GEL, p = 0.040), indicating increased fat oxidation. RQ during the MTT was significantly lower with the BB treatment (0.84) compared to GEL control (0.85), p = 0.004. A 4 h time isolation during dinner showed similar treatment effects, where RQ was reduced and fat oxidation increased with BB (0.818 vs. 0.836, 28 vs. 25 g, respectively; BB vs. GEL treatments). The glucose AUC was not different between the BB and GEL treatments during the MTT (3488 vs. 4070 mg·min/dL, respectively, p = 0.12). However, the insulin AUC was significantly lower with the BB compared to the GEL control (6485 vs. 8245 µU·min/mL, p = 0.0002), and HOMA-IR improved with BB ( p = 0.0318). Blackberry consumption may promote increased fat oxidation and improved insulin sensitivity in overweight or obese males fed a high fat diet.

As evidence mounts for a health-protective role of dietary phenolics, the importance of understanding factors influencing bioavailability increases. Recent evidence has suggested chronic exposure to phenolics may impact their absorption and metabolism. To explore alterations occurring from chronic dietary exposure to phenolics, Caco-2 cell monolayers were differentiated on Transwell inserts with 0-10 μM blackberry (Rubus sp.) total phenolics extracts rich in anthocyanins, flavonols, and phenolic acids. Following differentiation, apical to basolateral transport of phenolics was assessed from an acute treatment of 100 μM blackberry phenolics from 0 to 4 h. Additionally, differences in gene expression of transport and phase II metabolizing systems including ABC transporters, organic anion transporters (OATs), and uridine 5'-diphospho (UDP) glucuronosyltransferases (UGTs) were probed. After 4 h, 1 μM pretreated monolayers showed a significant (P < 0.05) decrease in the percentage of cumulative transport including less epicatechin (42.1 ± 0.53), kaempferol glucoside (23.5 ± 0.29), and dicaffeoylquinic acid (31.9 ± 0.20) compared to control. Finally, significant (P < 0.05) alterations in mRNA expression of key phase II metabolizing enzymes and transport proteins were observed with treatment. Therefore, adaptation to blackberry extract exposure may impact intestinal transport and metabolism of phenolics.

The relatively low oral bioavailability of flavan-3-ols from acute doses is commonly highlighted as a limitation when considering the biological significance of these compounds. However, evidence suggests that the absorption of flavan-3-ols may be enhanced during periods of repeated exposure which is more representative of dietary patterns. To explore changes occurring in the upper small intestine from repeated exposure to dietary flavan-3-ols, Caco-2 human intestinal cells were cultured and differentiated in the presence of isolated flavan-3-ols epigallocatechin gallate (EGCG) and epicatechin (EC) or flavan-3-ol-rich green tea and grape seed extracts. Following differentiation, cellular accumulation, Phase II metabolism, and transcellular transport were assessed from a final acute dose of the respective pretreated compound or extract. 10 μM EGCG pretreatment significantly (P < 0.05) decreased the appearance rate of both sulfated and methyl sulfate EGCG metabolites compared to the control. In contrast, 10 μM EC pretreatment resulted in a significantly greater appearance of methylated EC from acute treatment. After 4 h, 10 μM green tea extract pretreatment resulted in a significant (P < 0.05) 38% greater cumulative transport of EC, in addition to 44-60% increased transport of EGCG and epicatechin gallate (ECG) at 60 min compared to the control. For monolayers pretreated with 10 μM grape seed extract, there was a significant (P < 0.05) 17-56% greater cumulative transport of C and EC after 4 h. Assessment of the mRNA expression of select xenobiotic and metabolizing genes revealed that pretreatment with green tea and grape seed extracts significantly (P < 0.05) increased the expression of COMT, ABCC2 and ABCB1. Overall, these results suggest that intestinal adaptation to both isolated flavan-3-ols and extracts rich in these compounds alters their intestinal transport and metabolism.

Interest in the application of phenolic compounds from the diet or supplements for the prevention of chronic diseases has grown substantially, but the efficacy of such approaches in humans is largely dependent on the bioavailability and metabolism of these compounds. Although food and dietary factors have been the focus of intense investigation, the impact of disease states such as obesity or diabetes on their absorption, metabolism, and eventual efficacy is important to consider. These factors must be understood in order to develop effective strategies that leverage bioactive phenolic compounds for the prevention of chronic disease. The goal of this review is to discuss the inducible metabolic systems that may be influenced by disease states and how these effects impact the bioavailability and metabolism of dietary phenolic compounds. Because current studies generally report that obesity and/or diabetes alter the absorption and excretion of these compounds, this review includes a description of the absorption, conjugation, and excretion pathways for phenolic compounds and how they are potentially altered in disease states. A possible mechanism that will be discussed related to the modulation of phenolic bioavailability and metabolism may be linked to increased inflammatory status from increased amounts of adipose tissue or elevated plasma glucose concentrations. Although more studies are needed, the translation of benefits derived from dietary phenolic compounds to individuals with obesity or diabetes may require the consideration of dosing strategies or be accompanied by adjunct therapies to improve the bioavailability of these compounds., Competing Interests: 2 Author disclosures: BW Redan, KK Buhman, JA Novotny, and MG Ferruzzi, no conflicts of interest., (© 2016 American Society for Nutrition.)

Each of the macronutrients-carbohydrate, protein, and fat-has a unique set of properties that influences health, but all are a source of energy. The optimal balance of their contribution to the diet has been a long-standing matter of debate. Over the past half century, thinking has progressed regarding the mechanisms by which each macronutrient may contribute to energy balance. At the beginning of this period, metabolic signals that initiated eating events (i.e., determined eating frequency) were emphasized. This was followed by an orientation to gut endocrine signals that purportedly modulate the size of eating events (i.e., determined portion size). Most recently, research attention has been directed to the brain, where the reward signals elicited by the macronutrients are viewed as potentially problematic (e.g., contribute to disordered eating). At this point, the predictive power of the macronutrients for energy intake remains limited.

Grape seed polyphenolic extract (GSPE) rich in the flavan-3-ols (+)-catechin and (-)-epicatechin beneficially modulates Alzheimer's Disease phenotypes in animal models. The parent molecules in the extract are converted to a series of methylated and glucuronidated derivatives. To fully characterize these metabolites and establish a robust quantitative assay of their levels in biological fluids, we have implemented a partial synthetic approach utilizing chemical methylation followed by enzymatic glucuronidation. Liquid chromatography/time-of-flight mass spectrometry (LC-TOF-MS) and nuclear magnetic resonance (NMR) spectroscopy were used to assign unequivocal structures to the compounds. An analytical method using solid-phase extraction and LC-MS/MS in selective reaction monitoring mode (SRM) was validated for their quantitation in plasma. These studies provide a basis for improvements in future work on the bioavailability, metabolism, and mechanism of action of metabolites derived from dietary flavan-3-ols in a range of interventions.

Though much attention has been devoted to phenolics in beans, to our knowledge no studies have been done to determine the effect commercial canning has on these compounds. Free and total phenolic concentration in 18 cultivars of raw beans and 9 cultivars of commercial canned beans was determined. Alkaline hydrolysis was used on samples prior to analysis by Folin-Ciocalteu's reagent (FCR) and ferric-reducing antioxidant power (FRAP). A correction for non-phenolic antioxidants, interferences, was then made. There is a significant difference between the free phenolics of canned and raw beans using FCR (P = 0.006) but not FRAP. There is also a significant difference in the total phenolics of canned and raw beans using FRAP (P = 0.006) but not FCR. When considered on a single serving basis, the amount of phenolics in canned beans is comparable to that provided by raw fruits and vegetables.