| 1. |
- Bohn, T., et al.
(författare)
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Mind the gap - deficits in our knowledge of aspects impacting bioavailability of phytochemicals and their metabolites - a position paper focusing on carotenoids and polyphenols
- 2015
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Ingår i: Molecular Nutrition and Food Research. - : Wiley. - 1613-4133 .- 1613-4125. ; 59:7, s. 1307-13231-17-1323
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Forskningsöversikt (refereegranskat)abstract
- Various secondary plant metabolites or phytochemicals, including polyphenols and carotenoids, have been associated with a variety of health benefits, such as reduced incidence of type 2 diabetes, cardiovascular diseases, and several types of cancer, most likely due to their involvement in ameliorating inflammatory and oxidative stress. However, discrepancies exist between their putative effects when comparing observational and intervention studies, especially when using pure compounds. These discrepancies may in part be explained by differences in intake levels and their bioavailability. Prior to exerting their bioactivity, these compounds must be made bioavailable, and considerable differences may arise due to their their matrix release, changes during digestion, uptake, metabolism, and biodistribution, even before considering dose and host related factors. Though many insights have been gained on factors affecting secondary plant metabolite bioavailability, many gaps still exist in our knowledge. In this position paper, we highlight several major gaps in our understanding of phytochemical bioavailability, including effects of food processing, changes during digestion, involvement of cellular transporters in influx/efflux through the gastrointestinal epithelium, changes during colonic fermentation, and their phase I and phase II metabolism following absorption.
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| 2. |
- Grundy, Myriam M.L., et al.
(författare)
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INFOGEST inter-laboratory recommendations for assaying gastric and pancreatic lipases activities prior to in vitro digestion studies
- 2021
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Ingår i: Journal of Functional Foods. - : Elsevier BV. - 1756-4646. ; 82
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Tidskriftsartikel (refereegranskat)abstract
- In vitro digestion studies often use animal digestive enzyme extracts as substitutes of human gastric and pancreatic secretions. Pancreatin from porcine origin is thus commonly used to provide relevant pancreatic enzymes such as proteases, amylase and lipase. Rabbit gastric extracts (RGE) have been recently introduced to provide gastric lipase in addition to pepsin. Before preparing simulated gastric and pancreatic extracts with targeted enzyme activities as described in in vitro digestion protocols, it is important to determine the activities of enzyme preparations using validated methods. The purpose of this inter-laboratory study within the INFOGEST network was to test the repeatability and reproducibility of lipase assays using the pH-stat technique for measuring the activities of gastric and pancreatic lipases from various sources. Twenty-one laboratories having different pH-stat devices received the same protocol with identical batches of RGE and two pancreatin sources. Lipase assays were performed using tributyrin as a substrate and three different amounts (50, 100 and 200 µg) of each enzyme preparation. The repeatability results within individual laboratories were satisfactory with coefficients of variation (CVs) ranging from 4 to 8% regardless of the enzyme amount tested. However, the inter-laboratory variability was high (CV > 15%) compared to existing standards for bioanalytical assays. We identified and weighted the contributions to inter-laboratory variability of several parameters associated with the various pH-stat equipment used in this study (e.g. reaction vessel volume and shape, stirring mode and rate, burette volume for the automated delivery of sodium hydroxide). Based on this, we established recommendations for improving the reproducibility of lipase assays using the pH-stat technique. Defining accurate and complete recommendations on how to correctly quantify activity levels of enzyme preparations is a gateway to promising comparison of in vitro data obtained from different laboratories following the same in vitro digestion protocol.
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| 3. |
- Langton, Maud, 1954, et al.
(författare)
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Microstructure control for ingredient processing
- 2006
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Ingår i: Gums and stabillisers for the food industry: 13th Gums and Stabilisers for the Food Industry Conference; Wrexham; United Kingdom; 20 June 2005 through 24 June 2005. - 0854046739 ; , s. 161-169
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Konferensbidrag (refereegranskat)
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| 4. |
- Abdollahi, Mehdi, 1985, et al.
(författare)
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Minimizing lipid oxidation during pH-shift processing of fish by-products by cross-processing with lingonberry press cake, shrimp shells or brown seaweed
- 2020
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Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 327
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Tidskriftsartikel (refereegranskat)abstract
- The potential of cross-processing herring or salmon by-products with brown seaweed, shrimp peeling by-products and lingonberry press cake (called “helpers”) to minimize lipid oxidation during acid/alkaline pH-shift protein isolation was evaluated. Lingonberry press cake remarkably reduced levels of lipid hydroperoxides, malondialdehyde (MDA) and 4-hydroxy-trans2-hexenal (HHE) in both herring and salmon protein isolates (PI) while seaweed and shrimp by-product mitigated generation of MDA and HHE in herring PI. The salmon PI, however, by itself had very low oxidation levels. Cross-processing reduced protein yield compared with the classical pH-shift process by diminishing protein solubility, but still, the alkaline process version was promising. The color of the PIs varied greatly between different process combinations, reflecting partitioning of natural pigments into isolates. Altogether, cross-processing seems a promising tool for inhibition of lipid oxidation during pH-shift processing of sensitive fish by-products, with the alkaline version and lingonberry press cake being closest at hand for further studies.
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| 5. |
- Alminger, Marie, 1957, et al.
(författare)
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Applicability of in vitro models in prediciting the in vivo bioavailability of lycopene and beta-carotene from differently processed soups
- 2012
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Ingår i: Food and Nutrition Sciences. - : Scientific Research Publishing, Inc.. - 2157-944X .- 2157-9458. ; 3:4, s. 477-489
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Tidskriftsartikel (refereegranskat)abstract
- Presently, there is no clear consensus on the best approach to estimate carotenoid bioavailability. The best alternative would be to use human studies, but they are labour-intensive and expensive and can only be used to investigate a lim-ited number of samples. Hence, a number of in vitro models have been developed to study pre-absorptive processes and factors affecting bioavailability. The question is, however, how well the results obtained by the various methods correlate to each other and to the in vivo situation. In the present paper, we have compared in vivo data from two human studies on differently processed soups containing carrots, tomato and broccoli, with results obtained by in vitro characterisation of the same soups. In vitro bioaccessibility was estimated by a static in vitro digestion investigating matrix release and micellarization of carotenoids and by uptake studies in a human intestinal cell line (Caco-2). In vivo data was obtained from clinical studies measuring total plasma carotenoid concentrations in human subjects after 4 weeks daily consumption of the soups. Comparison of the in vitro and in vivo results indicate that the combination of a two-step in vitro digestion and Caco-2 cells seems to be a useful tool for estimation of β-carotene bioaccessibility and screening of factors governing the release of β-carotene from this type of food. For lycopene the in vitro and in vivo results were less consistent, suggesting that reliable prediction of lycopene bioavailability might be more problematic.
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| 6. |
- Alminger, Marie, 1957, et al.
(författare)
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In Vitro Models for Studying Secondary Plant Metabolite Digestion and Bioaccessibility
- 2014
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Ingår i: Comprehensive Reviews in Food Science and Food Safety. - : Wiley. - 1541-4337. ; 13:4, s. 413-436
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Forskningsöversikt (refereegranskat)abstract
- There is an increased interest in secondary plant metabolites, such as polyphenols and carotenoids, due to their proposed health benefits. Much attention has focused on their bioavailability, a prerequisite for further physiological functions. As human studies are time consuming, costly, and restricted by ethical concerns, in vitro models for investigating the effects of digestion on these compounds have been developed and employed to predict their release from the food matrix, bioaccessibility, and assess changes in their profiles prior to absorption. Most typically, models simulate digestion in the oral cavity, the stomach, the small intestine, and, occasionally, the large intestine. A plethora of models have been reported, the choice mostly driven by the type of phytochemical studied, whether the purpose is screening or studying under close physiological conditions, and the availability of the model systems. Unfortunately, the diversity of model conditions has hampered the ability to compare results across different studies. For example, there is substantial variability in the time of digestion, concentrations of salts, enzymes, and bile acids used, pH, the inclusion of various digestion stages; and whether chosen conditions are static (with fixed concentrations of enzymes, bile salts, digesta, and so on) or dynamic (varying concentrations of these constituents). This review presents an overview of models that have been employed to study the digestion of both lipophilic and hydrophilic phytochemicals, comparing digestive conditions in vitro and in vivo and, finally, suggests a set of parameters for static models that resemble physiological conditions.
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| 7. |
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| 8. |
- Alminger, Marie, 1957, et al.
(författare)
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Whole-grain cereal products based on a high-fibre barley or oat genotype lower post-prandial glucose and insulin responses in healthy humans
- 2008
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Ingår i: European Journal of Nutrition. - : Springer Science and Business Media LLC. - 1436-6207 .- 1436-6215. ; 47:6, s. 294-300
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Tidskriftsartikel (refereegranskat)abstract
- Background: Several factors can affect glycemic and insulinemic responses from cereal foods. Some suggested factors lowering the responses are; intact botanical structure, high amylose/high β-glucan cereal varieties, organic acid produced during fermentation and food processes inducing retrogradation of starch. Aim of the study: To evaluate the impact of fermented whole grain cereal kernels with high content of amylose (40%) and/or β-glucan (4.6%) on postprandial glucose and insulin responses in healthy adults. Methods: Thirteen healthy volunteers (4 men and 9 women) were given 25 g available carbohydrate portions of: glucose solution; tempe fermented whole-grain barley and tempe fermented whole-grain oat. Blood samples were collected directly before the meal (fasting) and 15, 30, 45, 60, 90 and 120 min after the start of the meal. The GI (glycemic index) and II (insulin index) of meals were calculated for each subject according to FAO/WHO standards. Results: Peak glucose response was lowest after the tempe meal with high-amylose/ high-β-glucan barley tempe while insulin response was lowest after the meal with high β-glucan oat tempe. The mean blood glucose responses for both the barley and the oat tempe meals were significantly lower than from the reference glucose load (P < 0.0001) during the first 60 min. The calculated GI:s for barley and oat tempe were 30 and 63, respectively. Mean serum insulin responses from barley and oat tempe were significantly lower compared with the glucose load (P < 0.002) during the first 60 min, and the calculated II was lower for oat tempe (21) compared with barley tempe (55). Conclusions: The results suggest that cereal products with beneficial influence on postprandial plasma glucose and insulin responses can be tailored by fermentation and enclosure of high-amylose and/or high-β-glucan barley and oat kernels. © 2008 Spinger.
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| 9. |
- Auer, Jaqueline, et al.
(författare)
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Assessing the digestibility and estimated bioavailability/bioaccessibility of plant-based protein from soy, pea and faba bean ingredients.
- 2024
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Ingår i: LWT - Food Science and Technology. - 1096-1127 .- 0023-6438. ; 197
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Tidskriftsartikel (refereegranskat)abstract
- Concerns have been raised about the nutritional adequacy of plant-based foods due to the presence of antinutrients and overall low protein digestibility. Therefore, this study characterizes the estimated bioavailability/bioaccessibility of iron and zinc and the protein digestibility of 11 commercially available plant-based ingredients to assess their potential in the future development of nutritious plant-based foods. The accessibility of iron and zinc was limited in all ingredients, with only faba bean isolate, pea isolate, faba bean concentrate and texturized pea containing accessible iron. Faba bean isolate was found to have the highest amount of accessible iron (67.4 mg/kg) whereas textured pea showed the lowest amount (0.5 mg/kg). The estimated bioavailability of iron and zinc, based on the calculated molar ratio of phytate, was low for all studied ingredients, with isolates showing the highest overall tendency for available iron and zinc. The amino acid composition data revealed limitations regarding valine and/or isoleucine in all protein concentrates and texturized proteins, soy isolate, and faba bean flour. In contrast, no significant differences were found in overall protein digestibility, suggesting that all tested raw materials, including faba bean, can be considered good protein sources.
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| 10. |
- Barbosa, Gabriel, 1980, et al.
(författare)
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Effects of pulsed electric field-assisted osmotic dehydration and edible coating on the recovery of anthocyanins from in vitro digested berries
- 2019
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Ingår i: Foods. - : MDPI AG. - 2304-8158. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- Berry fruits, such as strawberries and blueberries, are rich sources of anthocyanins. Several studies have been made on the impact of non-thermal treatments on safety, shelf-life and nutritional characteristics of such products, but the effects of these processes on anthocyanin stability during digestion in the gastrointestinal tract are still not completely clear. The aim of this study was to assess the recovery of anthocyanins after simulated gastrointestinal digestion of (1) strawberry samples, pre-treated with pulsed electric field (PEF) at 100 or 200 V·cm−1, prior to osmotic dehydration (OD), and (2) blueberry samples coated with chitosan and procyanidin. After digestion, a significantly higher content of cyanidin-3-O-glucoside and malvidin-3-O-glucoside was quantified by LC-MS/MS in processed strawberry and blueberry samples, compared with the controls. The highest recovery of cyanidin-3-O-glucoside was detected in digested strawberry samples osmotically dehydrated with trehalose. The recovery of malvidin-3-O-glucoside was highest in digested blueberries coated with chitosan and stored for 14 days, compared with untreated samples or samples coated with chitosan and procyanidin. Our study shows the potential of mild PEF treatments combined with OD, or the use of edible coating, to obtain shelf-stable products without substantially affecting the composition or the stability of anthocyanins during digestion in the upper gastrointestinal tract.
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