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The purpose of this paper is to focus on the antioxidant properties of two phenolic-rich varieties of Nigerian local rice and their anti-cholinesterase potential after in vitro-simulated gastrointestinal digestion, with the aim of establishing their actual antioxidant and nutraceutical potential after their passage through the gastrointestinal tract upon consumption.

Two local rice varieties, commonly referred to as “Gboko” and “Ofada” rice commonly grown in Benue State, a middle belt region of Nigeria and south western regions of Nigeria, respectively, were locally processed. Each of the processed grains were divided into two portions; one portion was left uncooked, while the second portion was boiled conventionally as eaten, dried and subsequently milled into powder. The milled samples of the raw and boiled rice were treated with acidified methanol to obtain the methanol extracts; another portion of each samples was subjected to in vitro enzyme digestion using standard methods to mimic human digestion; and the third portion was treated using the same scheme of in vitro digestion without the sets of enzyme which was used to serve as a control for enzyme treatment. The quali-quantitative phenolic profiles of the two local varieties were carried out with the aid of high-performance liquid chromatography with diode-array detection (HPLC-DAD) method. The antioxidant potential and anti-cholinesterase action of the methanolic extracts, the simulated in vitro digested model and the enzyme-treated controls of the rice samples were determined using standard methods and data obtained were subjected to ANOVA; the differences of means were separated using Duncan’s multiple range test (DMRT).

The quali-quantitative assessment of phenolic compounds in the two studied local varieties revealed the presence of some phenolic acids and flavonoids, with a decreased level of most of the identified phenolic compounds after boiling. In vitro enzyme-digested rice for both raw and boiled rice samples showed significantly higher total phenolic content, total flavonoid content, ferric-reducing antioxidant power, 2, 2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS+) scavenging and NO− inhibitory activities than the aqueous-methanolic extracts and the enzyme-treated controls. The aqueous-methanolic extracts displayed a higher 1, 1 diphenyl-2-picrylhdrazyl radical scavenging activity and inhibited Fe2+-induced lipid oxidation in rat’s brain and liver homogenate than that displayed by the in vitro enzyme-digested samples. In vitro enzyme-digested and boiled “Gboko” and “Ofada” rice and raw “Ofada” rice have the potential of inhibiting acetylcholine esterase (AChE) activity. While methanolic extracts of raw and boiled “Ofada” and “Gboko” rice exhibited the potential to inhibit butrylcholinesterase activity. The result of this paper indicates that the selected rice varieties possess antioxidant capacities which are better released after the simulated in vitro enzyme digestion; the result also showed the anti-cholinesterase potential of the studied rice grains and, therefore, they can be considered as nutraceutical health supplements.

The paper has demonstrated the antioxidant potentials of the phenolic-containing two Nigerian local rice varieties and established their anti-cholinesterase potential after simulated in vitro enzyme digestion.

This study aimed to evaluate the compositional changes and bioaccessibility of phenolics and antioxidants in propolis during in vitro digestion as well as the cytotoxic effects of digested propolis on various cancer cell lines.

Six propolis samples were obtained and subjected to in vitro oral, gastric and intestinal digestion. Both digested and undigested samples were analyzed for their total phenolic, flavonoid and antioxidant activities. Additionally, changes in phenolic composition in the in vitro digestion system were revealed by the HPLC-DAD system. The cytotoxic effects of the digested samples were assessed on lung (A549, H1299), skin (A431), liver (Hep-G2) and colon (Caco-2) cancer cells as well as on fibroblast (Bj) cells.

The mean bioaccessibility values of phenolic and flavonoid compounds were found to be less than 35 and 24%, respectively, while the TEAC and CUPRAC antioxidant results ranged between 225.08–649.04 and 398.68–1552.28 µmol TE/g, respectively. The release of p-coumaric, ferulic, 3,4-dimethoxycinnamic acids, naringenin, pinocembrin and chrysin increased progressively from the oral to the intestinal stage. The cytotoxic effects of samples on cell lines were ranked, based on IC50 results, as A431 > Hep-G2 > Caco-2 > A549 > H1299 > Bj.

Propolis has been recognized for centuries as a natural remedy, and numerous studies have explored its bioactive components. However, no studies have previously examined the changes in the phenolic compositions of propolis samples during digestion or their cytotoxic effects on cancer cells. Therefore, this study provides novel insights and an approach to the existing literature on this topic.

Sargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food safety, but it can alter both the contents of elements along with speciation and bioavailability. Three common cooking methods, the soaking, steaming and boiling, were evaluated for their effects on the protein structures, protein digestibility, iodine content and iodine bioavailability of S. fusiforme.

Fourier transform infrared spectroscopy was used to study the structural changes of protein, and an in vitro digestion/Caco-2 cell culture system was used to evaluate the digestibility of protein, bioaccessibility and bioavailability of iodine.

Boiling and steaming altered the protein secondary structure demonstrated by increased a-helix and random coil and decreased β-sheet, which improved the in vitro protein digestibility. Iodine content was reduced by cooking, with the highest loss observed after boiling, followed by soaking and steaming, while it was found that both bioaccessibility and cellular uptake of iodine were significantly elevated by boiling and steaming using an in vitro digestion/Caco-2 cell culture system. The presence of ascorbic acid, citric acid or tyrosine was beneficial for the iodine absorption, while oxalic acid and phytic acid hindered the iodine bioavailability.

The present finding suggested that cooking was conducive to the digestion and absorption of iodine in S. fusiforme. In addition, different dietary factors could have a certain impact on the absorption of iodine. Results of the study are essential for improving the application value of S. fusiforme to ensure reasonable consumption of seaweeds.

The bioavailability of iron from faba bean is low because it is present as an insoluble complex with food components such as phytate, fiber and tannin. The purpose of this paper is to try to identify the nature of the complexes between anti‐nutritional factors and iron in faba bean and legume fractions by using simulations of gastro‐intestinal digestion.

To this aim, the authors evaluated the effect of the action of fiber‐ and/or phytate‐degrading enzymes on solubilization of iron from insoluble residues obtained after gastro‐intestinal digestion of faba bean flour and fractions.

In insoluble residues of raw faba bean flour, simultaneous action of cellulase and phytases made it possible to release about 28 percent units more iron than that released with the treatment without enzymes. About 49.8 percent of iron in raw faba bean flour was solubilized after in vitro digestion and simultaneous action of cellulase and phytase. In the residues of the hull fraction, a significant increase in iron solubility has not been seen (p>0.05) after action of cellulase or phytases. Simultaneous action of cellulase and phytase led to the release of more than 60 and 18 percent units of additional iron for residues of dehulled faba bean and hull fractions, respectively.

In dehulled faba bean, iron was chelated by phytates and fibers. In the hull of faba bean, a high proportion of iron was chelated by iron‐tannins, while the rest of iron was chelated in complexes between phytates and fibers.

The purpose of this paper was to develop a loaf bread enriched with naranjilla (lulo) fruit (shells, seeds and pulp) and determine the technical quality, sensory acceptability and bioavailability (by in vitro digestion) of antioxidant components.

Loaf bread was prepared by using a no-time bread-making process. The crumb moisture, specific volume, crust and crumb color, texture profile analysis, analysis of the crumbs' alveoli, sensory evaluation, in vitro simulation of gastrointestinal digestion and antioxidant capacity were determined. Data were analyzed with one-way ANOVA (α = 0.05).

The specific volume was reduced by 21% (4.62 cm3/g, p < 0.0001), and the hardness was increased by 70% (2.9 N, p < 0.0001). Enrichment of the bread with naranjilla fruit (NF) contributes a yellowish coloration to the bread, which was very well accepted by the consumers and could be considered a natural colorant alternative. Moreover, the sensory evaluation indicated that the analyzed attributes (appearance, color, odor, taste, firmness and overall quality) of the naranjilla bread presented scores higher than 6.5 of 9 points hedonic scale. Naranjilla in the bread formulation had good acceptability by consumers. Naranjilla-enriched bread had an increase in total phenolic (TP)compounds and total carotenoids. In the product without digestion, naranjilla bread increased 1.7 times for TP, 50 times for CT and 1.3 times for TEAC, compared to the control bread (p < 0.0001). The percentage of bioaccessibility for fresh bread without digestion was 39.2 and 53.9% for the control and naranjilla bread, respectively. The addition of NF contributes to a higher TP compounds content and favors its bioavailability.

For bread production, fruits that do not meet the quality standards to be consumed as a natural fruit can be used. In this way, these fruits can contribute as a potential use to reduce agro-industrial waste and as a natural colorant.

Naranjilla is a native fruit from the subtropical Andean regions, which has high ascorbic acid concentrations, making it a fruit rich in antioxidants. Naranjilla-enriched bread contributes with beneficial compounds for the consumer.

Tea contains high content of phenolics which are well-known to act as antioxidants. As such, there are claims that the consumption of infusion of tea could help ameliorate free radical-induced diseases; this therapeutic activity would depend on the amount of phenolics that is soluble and the amount that is absorbed and available for metabolic activity when consumed. The purpose of this study is to analyze the content of phenolics and antioxidant activity of some health tea and also to study the effect of addition of sugar and milk on in-vitro availability of phenolics in tea, cocoa and coffee drinks.

Seven brands of health tea, two brands of cocoa drink, one brand each of coffee, powdered milk and sugar were selected. The tea samples were analyzed for pH, titratable acidity, total phenol and antioxidant activity using Folin–Ciocalteau and 202-diphenyl-1-picryl-hydrazil 28DPPH-29-20 reagents. In-vitro simulated digestion modeling stomach and small intestine were carried out on tea infusion, coffee and cocoa drinks with or without sugar, and phenolic availability was analyzed.

The result indicated that pH, titratable acidity and total phenolics ranged from 4.5 to 5.6, 0.167 to 0.837 (as maleic acid) and 1.15 to 1.17 mg/g gallic acid equivalent, respectively. Black tea recorded the highest phenolic content, in-vitro phenolic availability and antioxidant activity. Addition of sugar to black tea and chocolate drink caused a significant decrease in the in-vitro available phenolics, while the addition of milk leads to a significant enhancement.

The data obtained in this study can be used nutritionally and commercially to show the impact of adding sugar or milk on the content of phenolics and their bioavailability in-vitro. The study justifies the claim that tea could help ameliorate free radical-induced health defects.

Assessment of antioxidant activity of food should not be based only on the content of total phenolics but on the amount that is bioavailable in the body system when the food is consumed.

Consumption of tea, cocoa and coffee drinks with milk and sugar have been found to enhance or inhibit phenolics. Therefore, the optimum level of these additives should be determined if the drinks were meant for therapeutic purposes.

Results obtained may provide some useful information for considering the bioavailability of phenolics present in tea and beverages in view of consumption/digestion in our body as well as interference of sugar and milk as the additives.

The purpose of this paper is to evaluate the effect of green tea polyphenols addition on physicochemical, microbiological and bioactive characteristics of yogurt.

Two incorporation methods of polyphenols were evaluated: direct addition or incorporated within protein particles of whey protein concentrate and gelatin. During yogurt’s shelf life, structure characteristics (water holding capacity, textural and rheological parameters), lactic acid bacteria (LAB) viability and polyphenols antioxidant activity were analyzed. Also, polyphenol bioaccesibility after in vitro digestion was evaluated.

Polyphenols addition (by the two methods used) did not affect the dynamics of the fermentation process, nor the LAB viability during storage. The color parameter a* for the yogurts with the highest polyphenol concentrations showed positive values (tending to red), but not visible to the naked eye. Because of the ability of polyphenols to interact with milk proteins, yogurts with polyphenols presented higher values in firmness and cohesiveness with respect to the control. Additionally, the incorporation of polyphenols in protein particles increased even more these parameters because of the higher protein content of these formulations. After simulated digestion, a high polyphenol bioaccesibility was observed, and the antioxidant activity was retained, which could be explained by the “protector” effect of the milk matrix.

Yogurt supplementation with green tea polyphenols is feasible for the development of functional food. However, the use of protein particles would not provide an extra benefit because milk proteins already act as protective molecules of polyphenols.

This study shows not only the physico-chemical implications of including polyphenols in yogurt but also their bioaccesibility after an in vitro digestion, revealing a suitable manner for delivery of antioxidants in a dairy product like yogurt.

The purpose of this paper is to study the effect of whey and whey components on the production of dialyzable non‐heme iron – an in vitro indicator of bioavailable forms of the mineral.

Whey, processed whey and whey components were mixed with ferric iron and digested in vitro with pepsin and pancreatin/bile using a dialysis bag containing bicarbonate for pH adjustment. Total and ferrous dialyzable iron were measured and compared to values from protein and non‐protein controls.

Whey produced much more dialyzable iron than egg albumin but less than deproteinized whey. Most of the iron was ferric. Whey protein concentrate was as effective as egg abumin but whey protein isolate, α‐lactalbumin and β‐lactoglobulin slightly reduced dialyzable iron formation. Milk salts produced more dialyzable iron than whey and about as much as deproteinized whey. The major component of whey producing dialyzable iron was citrate, which competes for iron chelation with the whey protein.

This study demonstrates that whey generates a large amount of dialyzable iron from ferric iron sources and that the iron is primarily due to chelation with citrate rather than to digestion of whey proteins. However, the effect of citrate is reduced by whey proteins.

This paper aims to focus on the antioxidant properties and consumer acceptability of biscuits produced from pearl millet (PM)–tiger nut (TN) composite blends, with the aim of encouraging the use of these under-utilised food crops in producing value-added products with nutraceutical potential.

PM grains and TN seeds were processed into flour and blended at ratios: 15:85 (A), 20:80 (B), 25:75 (C), 30:70 (D), 35:65 (E), 40:60 (F), 45:55 (G), of PM to TN using response surface methodology. The antioxidant properties of the biscuits produced from the flour blends were determined using standard methods, and data obtained were subjected to analysis of variance (ANOVA); differences of means were separated using Duncan multiple range test. The biscuits were subjected to sensory evaluation using 50 untrained panellist and results statistically analysed.

The total phenolic content (TPC-mg/GAE) of PM–TN flour blends ranged from 2.65-4.95 (A-G), with an average TPC of 3.85. In PM–TN biscuits, total phenolic values ranged from 1.20-3.42 (A-G), with an average of 2.39. The 2,2′-azino-bis(3-ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activities (μmolTEAC/g) of PM–TN flour blends ranged from 26.7-36.4 (A-G), and the values for biscuits ranged from 28.5-38.6 (A-G). There was a highly significant correlation, r = 0.811(p < 0.001) and r = 0.913 (p < 0.001) between phenolic content and antioxidant activity for flour and biscuit, respectively. The effect of in vitro digestion of biscuits on the antioxidant assays viz-a-viz: TPC and ABTS radical scavenging activities were also investigated. The order of phenolic release was enzymic > aqueous > ethanolic digest for TPC, while for ABTS, the order of release was enzymic > ethanolic > aqueous. The highest values for antioxidant properties were found in the simulated in vitro enzyme digested biscuits. Consumer acceptability revealed that the overall acceptability scores of the biscuits were not significantly different except for biscuit sample G.

The paper has demonstrated the antioxidant potentials and consumer acceptability of PM–TN biscuits. It also shows the effect of in vitro digestion on the antioxidant activities of the biscuit and its potential health benefit, as a source of antioxidant.

The aim of the article was to focus on various peptides identified in the egg and their probable application as novel ingredients in the development of functional food products. Bioactive peptides of egg origin have attracted increasing interest as one of the prominent candidates for development of various health-promoting functional and designer foods.

Traditionally known as a source of highly valuable proteins in human nutrition, eggs are nowadays also considered as an important source of many bioactive peptides which may find wide application in medicine and food production. These specific protein fragments from egg proteins which, above and beyond their nutritional capabilities, have a positive impact on the body’s function or condition by affecting the digestive, endocrine, cardiovascular, immune and nervous systems, and may ultimately influence health.

Several peptides that are released in vitro or in vivo from egg proteins have been attributed to different health effects, including antihypertensive effects, antimicrobial properties, antioxidant activities, anticancer activity, immunomodulating activity, antiadhesive properties and enhancement of nutrient absorption and/or bioavailability. Extensive research has been undertaken to identify and characterize these biologically active peptides of egg origin which has changed the image of egg as a new source of biologically active ingredients for the development of functional foods with specific benefits for human health and treatment and prevention of diseases.

The paper mainly describes the above-stated properties of bioactive peptides derived from egg proteins.