Anti-diabetic properties of brewer's spent yeast peptides. In vitro, in silico and ex vivo study after simulated gastrointestinal digestion

Brewer's spent yeast (BSY) hydrolysates are a source of antidiabetic peptides. Nevertheless, the impact of in vitro gastrointestinal digestion of BSY derived peptides on diabetes has not been assessed. In this study, two BSY hydrolysates were obtained (H1 and H2) using β-glucanase and alkaline protease, with either 1 h or 2 h hydrolysis time for H1 and H2, respectively. These hydrolysates were then subjected to simulated gastrointestinal digestion (SGID), obtaining dialysates D1 and D2, respectively. BSY hydrolysates inhibited the activity of α-glucosidase and dipeptidyl peptidase IV (DPP-IV) enzymes. Moreover, although D2 was inactive against these enzymes, D1 IC50 value was lower than those found for the hydrolysates. Interestingly, after electrophoretic separation, D1 mannose-linked peptides showed the highest α-glucosidase inhibitory activity, while non-glycosylated peptides had the highest DPP-IV inhibitory activity. Kinetic analyses showed a non-competitive mechanism in both cases. After peptide identification, GILFVGSGVSGGEEGAR and IINEPTAAAIAYGLDK showed the highest in silico anti-diabetic activities among mannose-linked and non-glycosylated peptides, respectively (AntiDMPpred score: 0.70 and 0.77). Molecular docking also indicated that these peptides act as non-competitive inhibitors. Finally, an ex vivo model of mouse jejunum organoids was used to study the effect of D1 on the expression of intestinal epithelial genes related to diabetes. The reduction of the expression of genes that codify lactase, sucrase-isomaltase and glucose transporter 2 was observed, as well as an increase in the expression of Gip (glucose-dependent insulinotropic peptide) and Glp1 (glucagon-like peptide 1). This is the first report to evaluate the anti-diabetic effect of BSY peptides in mouse jejunum organoids.

Bio-functional and prebiotics properties of products based on whole grain sorghum fermented with lactic acid bacteria

BACKGROUND

Products fermented with lactic acid bacteria based on whole grain flours of red or white sorghum (Sorghum bicolor (L.) Moench) added with malted sorghum flour, or with skim milk (SM) were developed. Composition, protein amino acid profile, total acidity, pH, prebiotic potential, and bio-functional properties after simulation of gastrointestinal digestion were evaluated.

RESULTS

In all cases, a pH of 4.5 was obtained in approximately 4.5 h. The products added with SM presented higher acidity. Products made only with sorghum presented higher total dietary fiber, but lower protein content than products with added SM, the last ones having higher lysine content. All products exhibited prebiotic potential, white sorghum being a better ingredient to promote the growth of probiotic bacteria. The addition of malted sorghum or SM significantly increased the bio-functional properties of the products: the sorghum fermented products added with SM presented the highest antioxidant (ABTS•+ inhibition, 4.7 ± 0.2 mM Trolox), antihypertensive (Angiotensin converting enzyme-I inhibition, 57.3 ± 0.5%) and antidiabetogenic (dipeptidyl-peptidase IV inhibition, 31.3 ± 2.1%) activities, while the products added with malted sorghum presented the highest antioxidant (reducing power, 1.6 ± 0.1 mg ascorbic acid equivalent/mL) and antidiabetogenic (α-amylase inhibition, 38.1 ± 0.9%) activities.

CONCLUSION

The fermented whole grain sorghum-based products could be commercially exploited by the food industry to expand the offer of the three high-growth markets: gluten-free products, plant-based products (products without SM), and functional foods. © 2023 Society of Chemical Industry.

Xanthan gum and pectin as beverage stabilizers reduce the digestive enzyme hydrolysis of antioxidant and antihypertensive peptides obtained from a brewery byproduct

An acidic beverage was formulated with xanthan gum (XG), pectin (P) and brewer spent grain (BSG) peptides with antioxidant and antihypertensive properties. The impact of hydrocolloids levels on peptide bioaccessibility was studied. Peptides were obtained from BSG using Purazyme and Flavourzyme enzymes. BSG peptides were fractionated by ultrafiltration (UF) and four fractions were obtained: F1 (>10 kDa), F2 (10-5 kDa), F3 (1-5 kDa), and F4 (<1 kDa). F3 showed the highest protein purity, ferulic acid content, proportion of amphipathic peptides, and bioactive properties (ABTS+ radical scavenging and ACE-I inhibitory activity). The identified peptides from F3 by tandem mass spectrometry were 138. In silico analysis showed that 26 identified peptides had ABTS+ inhibitory activity, while 59 ones presented good antihypertensive properties. The effect of XG and P levels on bioaccessibility of F3 peptides in the formulated beverages was studied by a central composite experimental design. It was observed that F3 peptides interacted with hydrocolloids by electrostatic forces at pH of formulated beverages. The addition of hydrocolloids to formulation modulated the release of the antioxidant peptides and protected the degradation of ACE-I inhibitory peptides from F3 during simulated gastrointestinal digestion. Finally, the level of hydrocolloids that produced intermediate viscosities in the formulated beverages improved the bioaccessibility of the F3 peptides.

In vivo and in silico study of antioxidant and anti-inflammatory effects on the liver-spleen axis of microencapsulated brewers' spent grain peptides

Metabolic syndrome (MS) is a cluster of risk factors for the development of cardiovascular disease and type 2 diabetes mellitus. Some dietary bioactive compounds such as peptides can exert dual antioxidant and anti-inflammatory effects. The aim of this study was to analyze the effects of microencapsulated brewers' spent grain peptides (BSG-P-MC) on hepatic injury, lipid peroxidation, oxidative stress and inflammation in the liver-spleen axis in Wistar rats fed with a sucrose-rich diet (SRD). Male rats received for 100 days a reference diet (RD), SRD or RD and SRD containing 700 mg per kg body weight per day of BSG-P-MC. The results demonstrated that BSG-P-MC reversed injury, lipid peroxidation, and oxidative stress in the liver. For the spleen, BSG-P-MC decreased the levels of lipid peroxidation, CAT activity, NFκB, PAI-1 and F4/80 protein mass levels with respect to the SRD-fed rats. Three peptides identified by LC-MS/MS from BSG-P-MC after in vitro gastrointestinal digestion showed high in silico free radical scavenging activity (LPRDPYVDPMAPLPR, ANLPRDPYVDPMAPLPRSGPE and ANLPRDPYVDPMAPLPR). Moreover, two identified peptides presented high in silico anti-inflammatory properties (LTIGDTVPNLELDSTHGKIR and VDPDEKDAQGQLPSRT). This study is the first report of antioxidant and anti-inflammatory properties of microencapsulated BSG-peptides exerted in the liver-spleen axis in a MS rodent model.

Microencapsulated bioactive peptides from brewer's spent grain promotes antihypertensive and antidiabetogenic effects on a hypertensive and insulin-resistant rat model

The effects of microcapsules containing brewer's spent grain (BSG) peptides were evaluated on a hypertensive/insulin-resistant rat model induced by a sucrose-rich diet (SRD) administration. Animals received for 100 days the control diet (CD), SRD, and CD and SRD diets supplemented with microencapsulated peptides (CD-P and SRD-P). During the experimental period, blood pressure was monitored. Glycemia, tissue glycogen content, nitric oxide, and the activity of enzymes related to hypertensive and diabetogenic mechanisms were determined. The consumption of SRD caused hypertensive and hyperglycemic effects compared to CD. However, the SRD-P group presented lower systolic pressure at the middle of ingestion, achieving similar values than the CD. The SRD-P rats decreased all enzymes' activities compared to the SRD reaching the values of CD, except for those of α-amylase in cecal content and DPP-IV in serum. It was possible to corroborate potential antihypertensive and antidiabetogenic in vivo effects of the microencapsulated BSG peptides. PRACTICAL APPLICATIONS: Brewer's spent grain (BSG) is the main waste obtained from brewing industry. Bioactive peptides obtained after an enzymatic hydrolysis of proteins with in vitro antihypertensive and antidiabetogenic activity have been described. However, to corroborate the action of these bioactive peptides, in vivo studies are necessary. In the present work, microcapsules containing bioactive peptides from BSG were administered on the rat model with induced hypertension and insulin-resistance, corroborating an in vivo antihypertensive and antidiabetogenic effects by inhibition of enzymes related with blood pressure regulation and glucose metabolism. This work demonstrated that microcapsules of BSG peptides could be included into functional foods formulations, or used as dietary supplement for improving health and the prevention of non-communicable diseases, adding value to the brewing process by-product.

Physical, structural and antioxidant properties of brewer's spent grain protein films

BACKGROUND

The development of brewer's spent grain protein (BSG-PC) films with potential active packaging properties was investigated. Films were prepared by casting protein dispersions at different pH values (2, 8, 11), plasticizers [polyethylene glycol (PEG) or glycerol] and levels (0-0.25 g g^-1 ) of PEG. Mechanical, water-barrier and solubility, optical, antioxidant (reducing power, ABTS^•+ and lipidic radical scavenging), and antimicrobial properties of films were determined. Also, the structural characteristics of films were evaluated by attenuated total reflectance-Fourier transform infrared spectroscopy.

RESULTS

Only films prepared at pH 2 and plasticized by PEG were homogeneous in appearance and could be manipulated; thus, different levels of PEG were studied at this pH. Higher PEG concentrations increased water solubility, water vapor permeability and elongation at break, and decreased tensile strength and elastic modulus. PEG increased α-helix structure only when 0.10 g PEG g-1 BSG-PC was used. This could be related to the better mechanical properties of F_0.10 films (higher tensile strength, and elastic modulus) with respect to the other films. Antioxidant activity depended on PEG concentration, whereas no antimicrobial properties against Bacillus cereus, Salmonella newport and Penicillium corylophylum were detected.

CONCLUSION

The formulations with 0.10 and 0.15 g PEG g^-1 BSG-PC appear to be the most promising, balancing mechanical, water-barrier properties and the antioxidant capacity of these films. Moreover, BSG proteins could be a cheap alternative for the preparation of biodegradable films, which are capable of being used as active food packaging. © 2020 Society of Chemical Industry.

Molecular action mechanism of anti-inflammatory hydrolysates obtained from brewers' spent grain

BACKGROUND

Brewers' spent grain (BSG) is a relevant, protein-rich by-product of the brewing process. Protein hydrolysates from different sources exert immune-regulatory actions activating toll-like receptors (TLRs), nuclear factor kappa B (NFκB), and mitogen-activated protein kinases (MAPKs). Effects of gastrointestinal digestion have been poorly studied. Here, we studied the immune-regulatory effect of BSG hydrolysates, and their in-vitro-digested products, on rat splenocytes, macrophages, and T lymphocytes RESULTS: In primary cultures of rat spleen cells, BSG hydrolysates induced interleukin 10 and tumor necrosis factor production in basal conditions. Under stimulation with lipopolysaccharide or concanavalin A, hydrolysates further induced interleukin 10 production. Tumor necrosis factor and interferon-γ were inhibited in lipopolysaccharide- and concanavalin-A-stimulated cells respectively. In vitro gastrointestinal digestion attenuated the observed effects. Splenic macrophages and T lymphocytes behaved in a similar fashion. In spleen cells from TLR2^-/- and TLR4^-/- mice, immune-regulatory effects were greatly reduced or abrogated. The study of signal transduction pathways indicated a major involvement of NFκB, and the contribution of MAPKs p38, c-Jun N-terminal kinase, and extracellular signal-regulated kinases 1 and 2.

CONCLUSION

BSG hydrolysates, like those obtained from other food sources, regulate the immune response, involving TLR2 and TLR4 and the activation of NFκB and MAPKs, an effect partly maintained after in vitro gastrointestinal digestion. Our data support the hypothesis of a shared, rather unspecific, mechanism of action of protein hydrolysates. © 2020 Society of Chemical Industry.

Modification of nutritional properties of whole rice flours (Oryza sativa L.) by soaking, germination, and extrusion

Modifications of nutritional properties (amino acids, available lysine, protein digestibility, fatty acids, fiber, inositol phosphate (IPs), free and bound phenolics, and antioxidant properties) of whole rice ingredients processed by soaking, germination, and/or extrusion cooking were evaluated. Soaking and germination reduced proteins by lixiviation and hydrolysis, respectively. Lysine was the limiting amino acid. Polyunsaturated fatty acids increased after germination. Protein digestibility was 100% for germinated rice, decreased to 75% after the extrusion process. Fiber content decreased around 73% after the extrusion of soaked and germinated flours. Soaking-extrusion combined processes produces >50% IPs reduction. Germination-extrusion produced flours with the highest antioxidant capacity (54 µmol trolox g^-1 ), which was in accordance with the highest content of free and bound phenolics (66 and 69 mg GA 100 g^-1 , respectively). Grain treatments changed nutritional properties of flours resulting in low antinutrient whole grain ingredients, which could be used to develop whole grain-based foods. PRACTICAL APPLICATIONS: Phytic acid (PA) is an antinutrient having negative effects on mineral bioavailability and protein digestibility. There are processes such as soaking, germination, and extrusion, which alone or combined can decrease PA. However, nutritional composition and functionality of flours can change. We observed PA was highly reduced by soaking or germination combined with extrusion and antioxidant capacity and phenolic content increased in germinated and germinated-extruded flours compared to the other treatments. These modified whole grain rice flours low in anti-nutrients could be used in the production of expanded products or pre-cooked ingredients to develop whole grain based foods nutritionally improved.

Antithrombotic Activity of Brewers' Spent Grain Peptides and their Effects on Blood Coagulation Pathways

Antithrombotic activity of brewers' spent grain peptides before and after simulated gastrointestinal digestion and their effects on blood coagulation pathways were evaluated. Two hydrolysates were produced using sequential enzymatic systems: alkaline protease + Flavourzyme (AF) and neutral protease + Flavourzyme (PF). Simulation of gastrointestinal digestion of AF and PF hydrolysates was made using porcine pepsin and pancreatin enzymes, obtaining the corresponding digested samples: AFD and PFD, respectively. Peptides were fractionated by ultrafiltration using a 1 kDa cut-off membrane. Hydrolysates had peptides with medium and low molecular weights (2100 and 500 Da, respectively), and Glu, Asp, Leu, Ala, and Phe were the most abundant amino acids. Gastrointestinal digested hydrolysates presented high proportion of small peptides (~500 Da), and higher amount of Val, Tyr, and Phe than hydrolysates. Mass spectrum (HDMS Q-TOF) of AFD-ultrafiltered fraction <1 kDa exhibited peptides from 500 to 1000 Da, which are not present in AF. PFD showed the generation of new peptides from 430 to 1070 Da. All samples showed thrombin inhibitory activity. However, no effect was observed on prothrombin time. Peptides <1 kDa from hydrolysates and digested samples delayed thrombin and thromboplastin time respect to the control (~63%). Also the samples showed thrombin inhibitory activity at common pathway level. Thus, brewers' spent grain peptides exerted their antithrombotic activity by inhibiting the intrinsic and common pathways of blood coagulation. This is the first report to demonstrate that brewers' spent grain peptides are able to delay clotting time after simulated gastrointestinal digestion.

Parboiling of sorghum grains as a strategy to improve endosperm yield and mineral content of refined flours

The aims were (i) to optimize the parboiling/decorticating process by assessing the effects of parboiling soaking temperature (60-80 ℃) and pearling time (4-6 min and 5.5-9.5 min for red and white sorghum) on endosperm yield and ash content, to obtain pregelatinized refined flours from parboiling sorghum (RF-PS) and (ii) to evaluate the final content of selected nutrients in RF-PS obtained in these optimal conditions. Endosperm yield decreased with the increase of pearling time, and a maximum around 70 ℃ soaking temperature was observed. Ash content decreased with increasing soaking temperature and pearling time. The optimal conditions of soaking temperature-pearling time were 73.3 ℃-4.8 min for red sorghum and 67.9 ℃-8.6 min for white sorghum, considering maximum endosperm yield and ash content lower than 0.65 g/100 g. In RF-PS obtained under optimal conditions, protein, lipid, Cu, and free polyphenols were higher in red sorghum than white sorghum (10.16 ± 0.62 vs. 9.42 ± 0.61 g/100 g, 0.89 ± 0.16 vs. 0.62 ± 0.11 g/100 g, 2.08 ± 0.21 vs. 1.88 ± 0.20 mg/kg, 79.51 ± 14.51 vs. 63.82 ± 4.33 mg/100 g). Fe, Zn, Ca, and Na were higher in white sorghum than red sorghum (20.61 ± 2.92 vs. 17.56 ± 0.98 mg/kg, 11.94 ± 0.84 vs. 9.58 ± 1.65 mg/kg, 87.45 ± 12.91 vs. 75.31 ± 12.57 mg/kg, 129.62 ± 9.03 vs. 102.69 ± 28.34 mg/kg). No difference was observed in the contents of ash, Mg, and K. It was possible to improve endosperm yield using a parboiling process prior to decortication. In addition, this process contributes to increase the mineral content in RF-PS.

Green Alga Ulva spp. Hydrolysates and Their Peptide Fractions Regulate Cytokine Production in Splenic Macrophages and Lymphocytes Involving the TLR4-NFκB/MAPK Pathways

Hydrolysates of food protein sources have immunomodulatory effects, which are of interest for use as functional foods. In this study, we have characterized the immune regulatory effect on rat splenocytes, macrophages and T lymphocytes of Ulva spp. hydrolysates and their peptide fractions with or without in vitro gastrointestinal digestion and/or ultrafiltration. IL-10 was induced in almost all conditions and cell types obtained from wild type animals. The induction was in general increased by ultrafiltration and in vitro gastrointestinal digestion. TNF was also induced in basal conditions. In turn, TNF and IFN-γ production was attenuated by the hydrolysate products in lipopolysaccharide or concanavalin A immune stimulated cells. Inhibitors for the activation of NFκB, MAPK p38 and JNK inhibited IL-10 induction in rat splenocytes. The response was dramatically attenuated in TLR4-/- cells, and only modestly in TLR2-/- cells. Food peptides from Ulva spp. genus exert anti-inflammatory effects in immune cells mediated by TLR4 and NFκB. Similarity with the immunomodulatory profile of protein hydrolysates from other sources suggests a common mechanism.

Bioactive Properties of Phaseolus lunatus (Lima Bean) and Vigna unguiculata (Cowpea) Hydrolyzates Incorporated into Pasta. Residual Activity after Pasta Cooking

The aims of the study were to study the inclusion of P. lunatus (PLH) and V. unguiculata (VUH) protein hydrolyzates with bioactive properties into a pasta-extruded product and determine residual activity after extrusion or pasta cooking. Both protein hydrolyzates showed angiotensin-converting enzyme inhibition (ACEI) and antioxidant activity (TEAC). PLH showed higher ACEI but lower TEAC than VUH (97.19 ± 0.23 vs. 91.95 ± 0.29 % and 244.7 ± 3.4 vs. 293.7 ± 3.3 μmol Trolox/g, respectively). They were included at 5 or 10 % into wheat pasta. Control pasta had the lowest ACEI activity or TEAC (22.01 ± 0.76 % or 14.14 ± 1.28 μmol Trolox/g, respectively). Higher activity remained in pasta with PLH than VUH after extrusion, and higher the level of addition, higher the ACEI was. Pasta had practically the same ACEI activity after cooking, thus active compounds were not lost by temperature or lixiviation. Regarding TEAC, higher activity remained in pasta with 10 % VUH (31.84 ± 0.17 μmol Trolox/g). Other samples with hydrolyzates had the same activity. After cooking, pasta with hydrolyzates had higher TEAC values than control, but these were not modified by the level of incorporation. Moreover, the profile changed because pasta with PLH had the highest TEAC values (21.39 ± 0.01 and 20.34 ± 0.15 for 5 or 10 % hydrolyzates, respectively). Cooking decreased this activity (~ 20 %), for all samples. Although a certain loss of antioxidant activity was observed, pasta could be a good vehicle for bioactive compounds becoming a functional food.

Chelating Properties of Peptides from Red Seaweed Pyropia columbina and Its Effect on Iron Bio-Accessibility

The aim of this work was to evaluate copper-chelating, iron-chelating and anticariogenic activity of peptides obtained by enzymatic hydrolysis of P. columbina protein concentrate and to study the effects of chelating peptides on iron bio-accessibility. Two hydrolyzates were obtained from P. columbina protein concentrate (PC) using two hydrolysis systems: alkaline protease (A) and alkaline protease + Flavourzyme (AF). FPLC gel filtration profile of PC shows a peak having molecular weight (MW) higher than 7000 Da (proteins). A and AF hydrolyzates had peptides with medium and low MW (1013 and 270 Da), respectively. Additionally, AF presented free amino acids with MW around 82 Da and higher content of His and Ser. Peptides from AF showed the highest chelating properties measured as copper-chelating activity (the lowest β-carotene oxidation rate: Ro; 0.7 min(-1)), iron-chelating activity (33%), and phosphorous and Ca(2+) release inhibition (87 and 81%, respectively). These properties could indicate antioxidant properties, promotion of iron absorption and anticariogenic activity, respectively. In fact, hydrolyzates promoted iron dialyzability (≈ 16%), values being higher than that found for P. columbina seaweed. Chelating peptides from both hydrolyzates can maintain the iron in a soluble and bio-accessible form after gastrointestinal digestion.

Extruded whole grain diets based on brown, soaked and germinated rice. Effects on the lipid profile and antioxidant status of growing Wistar rats. Part II

The influence of whole grain (WG) rice based diets on the lipid profile and antioxidant status was evaluated.

Extruded whole grain diets based on brown, soaked and germinated rice. Effects on cecum health, calcium absorption and bone parameters of growing Wistar rats. Part I

The influence of diets with whole rice processed ingredients on cecum health, calcium absorption and bone parameters was studied using an animal model.

Proteins and Carbohydrates from Red Seaweeds: Evidence for Beneficial Effects on Gut Function and Microbiota

Based on their composition, marine algae, and namely red seaweeds, are good potential functional foods. Intestinal mucosal barrier function refers to the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules. Here, we will first outline the component of seaweeds and will summarize the effects of these on the regulation of mucosal barrier function. Special attention will be paid to unique components of red seaweeds: proteins and derived peptides (e.g., phycobiliproteins, glycoproteins that contain “cellulose binding domains”, phycolectins and the related mycosporine-like amino acids) together with polysaccharides (e.g., floridean starch and sulfated galactans, such as carrageenans, agarans and “dl-hybrid”) and minerals. These compounds have been shown to exert prebiotic effects, to regulate intestinal epithelial cell, macrophage and lymphocyte proliferation and differentiation and to modulate the immune response. Molecular mechanisms of action of peptides and polysaccharides are starting to be elucidated, and evidence indicating the involvement of epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGFR), Toll-like receptors (TLR) and signal transduction pathways mediated by protein kinase B (PKB or AKT), nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPK) will also be summarized. The need for further research is clear, but in vivo experiments point to an overall antiinflammatory effect of these algae, indicating that they can reinforce membrane barrier function.

Physicochemical properties and structural characteristics of whole grain Oryza sativa L. with different treatments

Physicochemical properties and structural characteristics of whole rice flours with different treatments (soaking, germination and extrusion cooking) were studied. Water solubility, water absorption, crystallinity, adsorption isotherms (BET and GAB models), and glass transition temperature of the samples were determined. Water solubility and water absorption were enhanced by extrusion cooking process (3.17–4.98 vs. 24.1–53.76 g/100 g and 2.77–3.05 vs. 4.46–7.04 ml/g, respectively), but crystallinity was decreased (30–33 vs. 4–16%). Adsorption isotherms showed that extruded samples exhibited higher equilibrium moisture content as compared with their corresponding non-extruded samples (5.0–19.2 vs. 4.0–16.1 g water/g solids). There were no changes in glass transition temperature values in the studied moisture range (3.8–16 g/100 g). These results allow the correct use of whole rice flours with different treatments in foods and also contributed to the knowledge of stabilization of the products.

Bioaccesibilidad de hierro de fortificación y zinc endógeno de fideos comerciales tipo spaghetti

Introducción: El presente trabajo tiene por objetivo evaluar la bioaccesibilidad y Aporte Potencial (AP) de Fe y Zn de Fideos Comerciales Fortificados (FCF), y la relación entre el tiempo de cocción y la pérdida de sólidos, Fe y Zn de dichos fideos.Material y métodos: Se analizaron cuatro diferentes marcas de FCF. Se evaluó la pérdida de sólidos, Fe y Zn, a dos tiempos de cocción (tiempo óptimo indicado por el fabricante y una sobrecocción de 10 minutos). La bioaccesibilidad de Fe y Zn se estimó a través del porcentaje del mineral dializado. El AP de minerales se determinó como el producto de la concentración y la dializabilidad de cada mineral.Resultados: Las pérdidas de sólidos resultaron inferiores al 7%, aún con sobrecocción. Tres de los cuatro FCF no cumplían con los valores declarados de contenido de Fe. Se produjeron grandes pérdidas de Fe y Zn durante la cocción, las cuales aumentaron al prolongarse el tiempo de cocción (de 43,7% a 64,7% para Fe; y de 7,7% a 15,2% para el Zn), siendo mayores las pérdidas de Fe (mineral de fortificación), que de Zn (mineral endógeno). La bioaccesibilidad de Fe y Zn resultó baja (0,82±0,27% y 0,90±0,45%, respectivamente) y el AP de una porción de 80 g de FCF sólo cubriría en promedio 0,646% de los requerimientos de Fe y 0,708% de los requerimientos de Zn.Conclusiones: Los resultados muestran que la fortificación de fideos contribuye muy poco a cubrir los requerimientos de los minerales analizados ya que gran parte se pierde en el agua de cocción.

Chemical composition, nutritional and antioxidant properties of the red edible seaweed Porphyra columbina

Proximate composition, fatty acids and amino acid profiles and nutritional (chemical score, protein digestibility, PDCAAS and mineral dialyzability) and antioxidant properties (TEAC, DPPH and power reduction) from Porphyra columbina were evaluated. Total dietary fiber (48.02 ± 1.13 g/100 g dry weight) and protein (24.61 ± 0.21 g/100 g dry weight) were the two most abundant components in this seaweed. The main saturated and unsaturated fatty acids were C16:0 and C20:5 (n-3), respectively. The limiting amino acid was tryptophan with a chemical score of 57%. Protein digestibility was 74.33 ± 3.0%. Porphyra columbina has high mineral content with good Na/K relationship and medium value of potential mineral accessibility (P, Ca and Zn dializability: 18.75 ± 0.01, 17.62 ± 0.16 and 16.70 ± 0.44, respectively). The highest antioxidant properties were obtained with an acetone/water extraction system. This work provides important information about chemical composition and nutraceutical new properties of P. columbina.

Development of naturally activated edible films with antioxidant properties prepared from red seaweed Porphyra columbina biopolymers

The aim of this work was to study the physicochemical and antioxidant properties of phycobiliproteins-phycocolloids-based films, obtained from mixtures of two aqueous fractions extracted from Porphyra columbina red seaweed, one enriched in phycocolloids (PcF) and the other in phycobiliproteins (PF). Films with different ratios of PF:PcF (0, 25, 50, 75, 100% [w/w]) and without plasticizer addition were prepared by casting. PcF films had excellent mechanical properties (tensile strength ∼50MPa, elongation at break ∼3% and an elastic modulus ∼17.5MPa). The addition of PF to formulations exerted a plasticizing effect on the PcF matrix, which was manifested in moisture content, water solubility and mechanical properties of the resulting films but not in its water vapour permeability. The antioxidant capacity (TEAC) of the PcF films was significantly increased by the addition of PF and a direct relationship between TEAC and the total phenolic compounds (r(2)=0.9998) and R-phycoerythrin (r(2)=0.9942) was observed.

Study of EDTA intake of children for potential use of FeNaEDTA for breakfast cereal fortification

EDTA is used as disodium salt or disodium-calcium in foods, to prevent lipid oxidation or as color and flavor stabilizer. In some countries, FeNaEDTA is also used as a source of iron for fortification. However, EDTA has an acceptable daily intake (ADI) of 2.5 mg/kg/day. The aim of this study was to estimate the intake of EDTA in children of school age and the potential use of FeNaEDTA as iron source for breakfast cereal fortification. A qualitative-quantitative food frequency questionnaire was conducted on 225 schoolchildren of both sexes, aged between 4 and 13, from school canteens, public and private schools, from the city of Santa Fe (Argentina). Only those foods which EDTA addition is allowed in Argentina: packaged ice cream, soda, soft drinks and powdered soft drinks (upper limit of Na2EDTA or Na2CaEDTA: 35 mg/kg) and dressings and margarines (upper limit of Na2CaEDTA: 75 mg/kg) were considered. EDTAAverage Daily Consumption (ADC) was 0.06 mg/kg/day with a median of 0.011 mg/kg/day, representing 2.4% of the ADI. In the hypothetical case that FeNaEDTA would be used as iron source for breakfast cereal fortification at level of 11 mg Fe%, the potential EDTA ADC would be 0.46 +/- 0.32 mg/kg/day, representing 18.4% of the ADI (2.5 mg/kg/day). Results indicate that children from Santa Fe city have an EDTA ADC currently well below the maximum ADI of EDTA, which would remain low even if FeNaEDTA is used for breakfast cereal fortification.

Immunomodulatory properties of the protein fraction from Phorphyra columbina

The phycobiliproteins from Rhodophyta , R-phycoerythrin (R-PE) and C-phycocyanin (C-PC), have been shown to exert immunomodulatory effects. This study evaluated the effects of a Phorphyra columbina protein fraction (PF) and R-PE and C-PC on rat primary splenocytes, macrophages, and T-lymphocytes in vitro. PF featured various protein species, including R-PE and C-PC. PF showed mitogenic effects on rat splenocytes and was nontoxic to cells except at 1 g L(-1) protein. IL-10 secretion was enhanced by PF in rat splenocytes, macrophages, and especially T-lymphocytes, whereas it was markedly diminished by R-PE and C-PC. The production of pro-inflammatory cytokines by macrophages was inhibited. The effect of PF on IL-10 was evoked by JNK/p38 MAPK and NF-κB-dependent pathways in macrophages and T-lymphocytes. It was concluded that PF has immunomodulatory effects on macrophages and lymphocytes that appear to be predominantly anti-inflammatory via up-regulated IL-10 production and cannot be accounted for by R-PE and C-PC.

[Iron and zinc in vitro potential availability in an infant diet with fortified bread with different iron sources or with the addition of different iron absorption promoters]

Home-made diets are the most frequently used complementary foods. In the present work we evaluated iron and zinc availability in a usually consumed infant diet containing either iron-fortified bread with different iron sources: ferrous sulfate, ferrous bisglycinate, NaFeEDTA. We also used non-fortified bread with absorption promoters: ascorbic acid, sodium citrate, Na2EDTA, combined with different beverages. The diet (potato, pumpkin, grits, bread, and apple) was combined with water, milk, tea, a soft drink and an orange-based artificial drink. Mineral dialyzability (D) as an indicator of potential availability was determined using an in vitro method. Statistical analysis was performed by ANOVA, and a posteriori Tukey test. There were no significant differences in FeD between diets with ferrous sulfate or ferrous bisglycinate fortified bread; in NaFeEDTA fortified bread it increased significantly (p<0.05). Iron D increase was greater in diets with bread containing absorption promoters than in those with fortified bread. The orange-based artificial drink increased FeD, while tea and milk decreased it significantly (p < 0.05). Zinc D increased significantly when the bread was fortified either with ferrous sulfate or NaFeEDTA, but remained unchanged in diets with ferrous bisglycinate fortified bread. The addition of tea or milk decreased ZnD while the orange-based artificial drink increased it significantly (p < 0.05). Regarding absorption promoters, the greater values both in FeD and ZnD were observed in diets with iron nonfortified bread containing Na2EDTA.