The aim was to evaluate the potential of nanocarriers, based on the coating of zein nanoparticles (ZNP) with a Gantrez (R) AN-PEG conjugate (GP), for the oral delivery of insulin. ZNP-GP displayed less negative surface charge and a 14-fold higher diffusion coefficient in pig intestinal mucus than ZNP. Both nanoparticles showed a spherical shape and an insulin load of 77.5 mu g/mg. Under simulated gastric conditions, ZNP-GP released significantly lower amount of insulin than ZNP, while under simulated intestinal conditions, both types of nanoparticles displayed similar behaviour. In Caenorhabditis elegans wild-type N2, grown under high glucose conditions, insulin treatments reduced glucose and fat accumulation without altering the growth rate, the worm length, or the pumping rate. The effect was significantly greater (p < 0.001) when insulin was nanoencapsulated in ZNP-GP compared with that encapsulated in ZNP or formulated in solution. This would be related to the highest capability of ZNP-GP to diffuse in the dense peritrophic-like layer covering intestinal cells in worms. In daf-2 mutants, the effect on fat and glucose reduction by insulin treatment was suppressed, indicating a DAF-2 dependent mechanism. In summary, ZNP-GP is a promising platform that may offer new opportunities for the oral delivery of insulin and other therapeutic proteins.

The metabolic properties of omega-6 fatty acid consumption are being increasingly accepted. We had previously observed that supplementation with a borage seed oil (BSO), as a source of linoleic (18:2n-6; LA) and gamma-linolenic (18:3n-6; GLA) acids, reduces body weight and visceral adiposity and improves insulin sensitivity in a diet-induced obesity model of Wistar rats. Here, it was investigated whether the anti-obesogenic properties of BSO could be maintained in a pre-obese model of rats, and if these effects are enhanced by a combination with low doses of quercetin, together with its potential role in the regulation of the adipocyte biology. The combination of BSO and quercetin during 8 weeks was able to ameliorate glucose intolerance and insulin resistance, and to improve liver steatosis. Although no effects were observed on body weight, animals supplemented with this combination exhibited a lower proportion of visceral adiposity. In addition, in vitro differentiation of epididymal adipose-precursor cells of the BSO-treated animals exhibited a down-regulation of Fasn, Glut4, Pparg and Srebp1 genes, in comparison with the control group. Finally, in vitro evaluation of the components of BSO demonstrated that the anti-adipogenic activity of quercetin was significantly potentiated by the combination with both LA and GLA through the down-regulation of different adipogenesis-key genes in 3T3-L1 cells. All these data suggest that omega-6 fatty acids LA and GLA, and their natural sources such as BSO, could be combined with quercetin to potentiate their effects in the prevention of the excess of adiposity and the insulin resistance.

The influence on the stability of Lactobacillus plantarum CECT 220 (25 C/60% relative humidity) of microencapsulation by simple coacervation followed by spray-drying using different Ca2þ-tosoybean protein isolate ratios was evaluated. After optimisation, the selected soybean protein concentrate (SPC) microparticles were used to evaluate the tolerance of L. plantarum under acidic conditions (lactic acid, pH¿4; and HCl, pH¿3) and heat stress (80 C for 1 min) in contrast to free cells. Moreover, after the heat treatment, the influence of the simulated gastric fluid was evaluated. Additionally, different foods were formulated using either microencapsulated or freeze-dried L. plantarum, and the stability of cells during the shelf-life of the formulated foods was studied. Results show that encapsulation with SPC enhanced significantly the stability of the Lactic Acid Bacteria all along the probiotic food value chain, from production to the end of the food shelf-life.

Supplementation with bioactive compounds capable of regulating energy homeostasis is a promising strategy to manage obesity. Here, we have screened the ability of different phenolic compounds (myricetin, kaempferol, naringin, hesperidin, apigenin, luteolin, resveratrol, curcumin and epicatechin), and phenolic acids (p-coumaric, ellagic, ferulic, gallic and vanillic acids) regulating C. elegans fat accumulation. Resveratrol exhibited the strongest lipid-reducing activity, which was accompanied by the improvement of lifespan, oxidative stress and ageing, without affecting worm development. Whole-genome expression microarrays demonstrated that resveratrol affected fat mobilization, fatty acid metabolism, and unfolded protein response of the endoplasmic reticulum (UPRER), mimicking the response to calorie restriction. Apigenin induced the oxidative stress response and lipid mobilization, while vanillic acid affected the unfolded-protein response in ER. In summary, our data demonstrates that phenolic compounds exert a lipid-reducing activity in C. elegans through different biological processes and signaling pathways, including those related with lipid mobilization and fatty acid metabolism, oxidative stress, ageing and UPR-ER response. These findings open the door to the possibility of combining them in order to achieve complementary activity against obesity-related disorders.

Brassicaceae contain bioactive compounds with potential positive effects on metabolic syndrome. Here, we evaluated the eventual anti-obesity properties of an ethanolic broccoli extract (BE), selected by a tested ability to reduce Caenorhabditis elegans fat content. Two doses (14 and 140 mg/kg animal) of BE were evaluated in a diet-induced obesity (DIO) Wistar rat model. After 10 weeks of BE supplementation, animals exhibited reduced body weight gain and food efficiency, decreased atherogenic index of plasma and improved glucose tolerance in comparison with non-supplemented rats. BE also reduced the retroperitoneal fat mass and adipocyte size, all associated to down-regulation of Cebpa, Srebp1, Fasn and Adipoq expression in adipocytes. Finally, BE significantly decreased liver steatosis, accompanied by the up-regulation of Acot8 and Acox1, and the down-regulation of Fasn, Fatp4 and Srebf1 expression in hepatocytes. Our data provides new knowledge about the potential role of broccoli components in the prevention of metabolic syndrome.

The aim of this work was to optimize the preparative process of quercetin loaded casein nanoparticles as well as to evaluate the pharmacokinetics of this flavonoid when administered orally in Wistar rats. Nanoparticles were obtained by coacervation after the incubation of casein, 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) and quercetin in an aqueous environment. Then, nanoparticles were purified and dried. The resulting nanoparticles displayed a size of 200 nm with a negative zeta potential and a payload of about 32 mu g/mg. Release studies showed a zero-order kinetic, suggesting a mechanism based on erosion of the nanoparticle matrix. For the pharmacokinetic study, quercetin was orally administered to rats as a single dose of 25 mg/kg. Animals treated with quercetin-loaded casein nanoparticles displayed higher plasma levels than those observed in animals receiving the solution of the flavonoid (control). Thus, the relative oral bioavailability of quercetin when administered as casein nanoparticles (close to 37%) was found to be about 9-times higher than the oral solution of the flavonoid in a mixture of PEG 400 and water. In summary, the combination of casein and 2-hydroxypropyl-beta-cyclodextrin produces nanoparticles that may be a good option to load quercetin for both nutraceutical and pharmaceutical purposes.

Cocoa polyphenols exhibit high antioxidant activity and have been proposed as a potential adjuvant for the treatment of metabolic disturbances. Here, we demonstrate that supplementation with low doses (14 and 140 mg per kg per rat) of a complete cocoa extract induces metabolic benefits in a diet-induced obesity (DIO) model of Wistar rats. After 10 weeks, cocoa extract-supplemented animals exhibited significantly lower body weight gain and food efficiency, with no differences in energy intake. Cocoa significantly reduced visceral (epididymal and retroperitoneal) and subcutaneous fat accumulation accompanied by a significant reduction in the adipocyte size, which was mediated by downregulation of the adipocyte-specific genes Cebpa, Fasn and Adipoq. Additionally, cocoa extract supplementation reduced the triacylglycerol/high density lipoprotein (TAG/HDL) ratio, decreased hepatic triglyceride accumulation, improved insulin sensitivity by reducing HOMA-IR, and significantly ameliorated glucose tolerance after an intraperitoneal glucose tolerance test. Finally, no adverse effect was observed in an in vivo toxicity evaluation of our cocoa extract at doses up to 500 mg kg -1 day -1. Our data demonstrate that low doses of cocoa extract supplementation (14 and 140 mg kg -1 day -1) are safe and sufficient to counteract obesity and type-2 diabetes in rats and provide new insights into the potential application of cocoa supplements in the management of the metabolic syndrome.

Phenolic compounds might modulate adiposity. Here, we report our observation that polyphenols and phenolic acids inhibit adipogenesis in 3T3-L1 with different intensity depending on the family and the stage of differentiation. While quercetin and resveratrol inhibited lipid accumulation along the whole process of differentiation, apigenin and myricetin were active during the early and latest stages, but not intermediate, contrary to hesperidin. The activity of phenolic acids was limited to the early stages of the differentiation process, except p-coumaric and ellagic acids. This anti-adipogenic effect was accompanied by down-regulation of Scd1 and Lpl. Molecular docking analysis revealed that the inhibitory activity of these phenolic compounds over the early stages of adipogenesis exhibits a significant correlation (r = 0.7034; p = 0.005) with their binding affinity to the ligand-binding domain of PPAR¿. Results show that polyphenols and phenolic acids would interact with specific residues of the receptor, which could determine their potential anti-adipogenic activity during the early stages of the differentiation. Residues Phe264, His266, Ile281, Cys285 and Met348 are the most frequently involved in these interactions, which might suggest a crucial role for these amino acids modulating the activity of the receptor. These data contribute to elucidate the possible mechanisms of phenolic compounds in the control of adipogenesis.

Obesity is a medical condition with increasing prevalence, characterized by an accumulation of excess fat that could be improved using some bioactive compounds. However, many of these compounds with in vitro activity fail to respond in vivo, probably due to the sophistication of the physiological energy regulatory networks. In this context, C. elegans has emerged as a plausible model for the identification and characterization of the effect of such compounds on fat storage in a complete organism. However, the results obtained in such a simple model are not easily extrapolated to more complex organisms such as mammals, which hinders its application in the short term. Therefore, it is necessary to obtain new experimental data about the evolutionary conservation of the mechanisms of fat loss between worms and mammals. Previously, we found that some omega-6 fatty acids promote fat loss in C. elegans by up-regulation of peroxisomal fatty acid ß-oxidation in an omega-3 independent manner. In this work, we prove that the omega-6 fatty acids¿ effects on worms are also seen when they are supplemented with a natural omega-6 source (borage seed oil, BSO). Additionally, we explore the anti-obesity effects of two doses of BSO in a diet-induced obesity rat model, validating the up-regulation of peroxisomal fatty acid ß-oxidation. The supplementation with BSO significantly reduces body weight gain and energy efficiency and prevents white adipose tissue accumulation without affecting food

This work describes the feasibility of poly(anhydride) nanoparticles as carriers for the oral administration of glibenclamide (GB) as well as the in vivo evaluation of their hypolipidemic effect in a C. elegans model. For this purpose, and in order to increase the GB payload, the drug was encapsulated in nanoparticles in presence of cyclodextrins (either ßCD or HPßCD). The optimized nanoparticles displayed a size of about 220¿nm and a negative zeta potential (-40¿mV), with a drug loading up to 52¿¿g/mg. Small-angle neutron scattering studies suggested an internal fractal-like structure, based on the repetition of spherical blocks of polymeric units (about 5¿nm) grouped to form the nanoparticle. X-ray diffraction study confirmed the absence of crystalline GB molecules due to its dispersion into the nanoparticles, either entrapped in the polymer chains and/or included into cyclodextrin cavities. GB-loaded nanoparticles induced a significant reduction in the fat content of C. elegans. This hypolipidemic effect was slightly higher for the nanoparticles prepared with coencapsulated HPßCD (8.2%) than for those prepared with ßCD (7.9%) or in the absence of cyclodextrins (7.0%). In summary, the coencapsulation of cyclodextrins into poly(anhydride) nanoparticles could be an interesting strategy to develop new oral formulations of glibenclamide.

Bioactive compounds, including some fatty acids (FAs), can induce beneficial effects on body fat-content and metabolism. In this work, we have used C. elegans as a model to examine the effects of several FAs on body fat accumulation. Both omega-3 and omega-6 fatty acids induced a reduction of fat content in C. elegans, with linoleic, gamma-linolenic and dihomo-gamma-linolenic acids being the most effective ones. These three FAs are sequential metabolites especially in omega-6 PUFA synthesis pathway and the effects seem to be primarily due to dihomo-gamma-linolenic acid, and independent of its transformation into omega-3 or arachidonic acid. Gene expression analyses suggest that peroxisomal beta oxidation is the main mechanism involved in the observed effect. These results point out the importance of further analysis of the activity of these omega-6 FAs, due to their potential application in obesity and related diseases.

Resveratrol is a naturally occurring polyphenol that provides several health benefits including cardioprotection and cancer prevention. However, its biological activity is limited by a poor bioavailability when taken orally. The aim of this work was to evaluate the capability of casein nanoparticles as oral carriers for resveratrol. Nanoparticles were prepared by a coacervation process, purified and dried by spray-drying. The mean size of nanoparticles was around 200 nm with a resveratrol payload close to 30 ¿g/mg nanoparticle. In vitro studies demonstrated that the resveratrol release from casein nanoparticles was not affected by the pH conditions and followed a zero-order kinetic. When nanoparticles were administered orally to rats, they remained within the gut, displaying an important capability to reach the intestinal epithelium. No evidence of nanoparticle "translocation" were observed. The resveratrol plasma levels were high and sustained for at least 8 h with a similar profile to that observed for the presence of the major metabolite in plasma. The oral bioavailability of resveratrol when loaded in casein nanoparticles was calculated to be 26.5%, 10 times higher than when the polyphenol was administered as oral solution. Finally, a good correlation between in vitro and in vivo data was observed.

The present work describes the encapsulation of probiotics using a by-product as wall material and a process feasible to be scaled-up: coacervation of soybean protein concentrate (SPC) by using calcium salts and spray-drying. SPC was extracted from soybean flour, produced during the processing of soybean milk, by alkaline extraction following isoelectric precipitation. Two probiotic strains were selected for encapsulation (Lactobacillus plantarum CECT 220 and Lactobacillus casei CECT 475) in order to evaluate the ability of SPC to encapsulate and protect bacteria from stress conditions. The viability of these encapsulated strains under in vitro gastrointestinal conditions and shelf-life during storage were compared with the most common forms commercialized nowadays. Results show that SPC is a feasible material for the development of probiotic microparticles with adequate physicochemical properties and enhanced significantly both probiotic viability and tolerance against simulated gastrointestinal fluids when compared to current available commercial forms.

Background: Eicosapentaenoic acid (EPA) and alpha-lipoic acid (alpha-LA) have been investigated for their beneficial effects on obesity and cardiovascular risk factors. In the current research, the goal was to evaluate metabolomic changes following the dietary supplementation of these two lipids, alone or combined in healthy overweight/obese sedentary women following an energy-restricted diet. For this purpose, an untargeted metabolomics approach was conducted on urine samples using liquid chromatography coupled with time of flight mass spectrometry (HPLC-TOF-MS). Methods: This is a short-term double blind placebo-controlled study with a parallel nutritional design that lasted 10 weeks. Participants were assigned to one of the 4 experimental groups [Control, EPA (1.3 g/d), alpha-LA (0.3 g/d) and EPA+alpha-LA (1.3 g/d + 0.3 g/d)]. All intervention groups followed an energy-restricted diet of 30% less than total energy expenditure. Clinically relevant biochemical measurements were analyzed. Urine samples (24 h) were collected at baseline and after 10 weeks. Untargeted metabolomic analysis on urine samples was carried out, and principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were performed for the pattern recognition and characteristic metabolites identification. Results: Urine samples were scattered in the PCA scores plots in response to the supplementation with alpha-LA. Totally, 28 putative discriminant metabolites in positive ionization, and 6 in negative ionization were identified among groups clearly differentiated according to the a-LA administration. Remarkably is the presence of an ascorbate intermediate metabolite (one of the isomers of trihydroxy-dioxohexanoate, or dihydroxy-oxohexanedionate) in the groups supplemented with aLA. This fact might be associated with antioxidant properties of both alpha-LA and ascorbic acid. Correlations between phenotypical parameters and putative metabolites of provided additional information on whether there is a direct or inverse relationship between them. Especially interesting are the negative correlation between ascorbate intermediate metabolite and asymmetric dimethylarginine (ADMA) and the positive one between superoxide dismutase (SOD) and aLA supplementation. Conclusions: This metabolomic approach supports that the beneficial effects of alpha-LA administration on body weight reduction may be partly explained by the antioxidant properties of this organosulfur carboxylic acid mediated by isomers of trihydroxy-dioxohexanoate, or dihydroxy-oxohexanedionate.

Obesity and type 2-diabetes are becoming a worldwide health problem, remarking the importance of alternative therapies to tackle their progression. Here, we hypothesized that supplementation of diet with 6 % w/w of a freeze-dried strawberry-blueberry (5:1) powder (FDSB) could exert beneficial metabolic effects in Wistar rats. FDSB-supplemented animals experienced significantly reduced body weight gain, food efficiency and visceral adiposity accumulation in two independent experiments. FDSB supplementation also contributed to lower area under the curve after an intraperitoneal GTT and reduced serum insulin levels and insulin resistance index (IR-HOMA) in HFS diet-fed animals, together with reduced plasma MCP-1 inflammation marker concentrations. Gene expression analysis in retroperitoneal adipocytes from experiment 1 and 3T3-L1 cells showed that FDSB inhibited adipogenesis and lipogenesis through down-regulation of Pparg, Cebpa, Lep, Fasn, Scd-1 and Lpl gene expression. Untargeted metabolomics identified the cis isomer ofresveratrol-3-glucoside-sulphate as a metabolite differentially increased in FDSB-treated serum samples, which corresponds to a strawberry metabolite that could be considered a serum biomarker of FDSB-intake. Our results suggest that FDSB powder might be useful for treatment/prevention of obesity-related diseases.

The aim of this work was to evaluate the capability of zein nanoparticles as oral carriers for glibenclamide (GB). Nanoparticles were prepared by a desolvation procedure in the presence of lysine as stabilizer. A central composite design was used to optimize this preparative process. Under the selected conditions, nanoparticles displayed a size of about 190 nm, a surface charge of -37 mV and a payload of 45 mu g GB/mg. Small-angle neutron scattering and X-ray diffraction techniques suggested an internal fractal-like structure, based on the repetition of spherical blocks of zein units (about 20 nm) grouped to form the nanoparticles. This structure, stabilized by lysine molecules located at the surface, would determine the release of GB (molecularly trapped into the nanoparticles) by a pure diffusion mechanism. Moreover, GB-loaded nanoparticles induced a significant hypolipidemic effect with a reduction of about 15% in the fat content of C. elegans worms. In addition, did not induce any significant modification in the lifespan of worms. In summary, the employment of zein nanoparticles as delivery systems of glibenclamide may be an interesting approach to develop new oral formulations of this antidiabetic drug.

In the last years, casein nanoparticles have been proposed as carriers for the oral delivery of biologically active compounds. However, till now, no information about their possible specific hazards in vivo was available. The aim of this work was to assess the safety of casein nanoparticles when administered orally to animals through a 90 days dose-repeated toxicity study (OECD guideline 408), that was performed in Wistar rats under GLP conditions. After 90 days, no evidences of significant alterations in animals treated daily with 50,150 or 500 mg/kg bw of nanoparticles were found. This safety agrees well with the fact that nanoparticles were not absorbed and remained within the gut as observed by radiolabelling in the biodistribution study. After 28 days, there was a generalized hyperchloremia in males and females treated with the highest dose of 500 mg/kg bw, that was coupled with hypernatremia in the females. These effects were related to the presence of mannitol which was used as excipient in the formulation of casein nanoparticles. According to these results, the No Observed Adverse Effect Level (NOAEL) could be established in 150 mg/kg bw/day and the Lowest Observed Effect Level (LOEL) could be established in 500 mg/kg bw/day. (C) 2017 Published by Elsevier Ltd.

Zein nanoparticles were evaluated as nanocarriers to promote the oral bioavailability of quercetin and, thus, improve its anti-inflammatory effect on a mouse model of induced endotoxemia. For this purpose, the flavonoid and 2-hydroxypropyl-ß-cyclodextrin were encapsulated in zein nanoparticles. The resulting nanoparticles displayed a mean size of about 300nm and the payload was calculated to be close to 70¿g/mg nanoparticle. The release of quercetin from zein nanoparticles followed a zero-order kinetic. After oral administration, nanoparticles provided high and sustained levels of quercetin in plasma and the relative oral bioavailability was calculated to be approx. 60%. Animals treated with quercetin-loaded nanoparticles (1 dose every two days; 1week) presented endotoxic symptoms less severe than those observed in animals treated with the oral solution of the flavonoid (1 dose every day; 1week). This was further corroborated by the significantly low circulating TNF-alpha in the quercetin-loaded nanoparticles treated mice.

Metabolomics is used to assess the compliance and bioavailability of food components, as well as to evaluate the metabolic changes associated with food consumption. This study aimed to analyze the effect of consuming ready-to-eat meals containing a cocoa extract, within an energy restricted diet on urinary metabolomic changes. Fifty middle-aged volunteers [30.6 (2.3) kg m(-2)] participated in a 4-week randomised, parallel and double-blind study. Half consumed meals supplemented with 1.4 g of cocoa extract (645 mg polyphenols) while the remaining subjects received meals without cocoa supplementation. Ready-to-eat meals were included within a 15% energy restricted diet. Urine samples (24 h) were collected at baseline and after 4 weeks and were analyzed by high-performance-liquid chromatography-time-of-flight-mass-spectrometry (HPLC-TOF-MS) in negative and positive ionization modes followed by multivariate analysis. The relationship between urinary metabolites was evaluated by the Spearman correlation test. Interestingly, the principal component analysis discriminated among the baseline group, control group at the endpoint and cocoa group at the endpoint (p < 0.01), although in the positive ionization mode the baseline and control groups were not well distinguished. Metabolites were related to theobromine metabolism (3-methylxanthine and 3-methyluric acid), food processing (L-beta-aspartyl-L-phenylalanine), flavonoids (2,5,7,3', 4'-pentahydroxyflavanone-5-O-glucoside and 7,4'-dimethoxy-6-C-methylflavanone), catecholamine (3-methoxy-4-hydroxyphenylglycol-sulphate) and endogenous metabolism (uridine monophosphate). These metabolites were present in higher (p < 0.001) amounts in the cocoa group. 3-Methylxanthine and L-beta-aspartyl-L-phenylalanine were confirmed with standards. Interestingly, 3-methoxy-4-hydroxyphenylglycol-sulphate was positively correlated with 3-methylxanthine (rho = 0.552; p < 0.001) and 7,4'-dimethoxy-6-C-methylflavanone (rho = 447; p = 0.002). In conclusion, the metabolomic approach supported the compliance of the volunteers with the intervention and suggested the bioavailability of cocoa compounds within the meals.

Food grade proteins can be viewed as an adequate material for the preparation of nanoparticles and microparticles. They offer several advantages such as their digestibility, price and a good capability to interact with a wide variety of compounds and nutrients. The aim of this work was to prepare and characterize casein nanoparticles for the oral delivery of folic acid. These nanoparticles were prepared by a coacervation process, stabilized with either lysine or arginine and, finally, dried by spray-drying. For some batches, the effect of a supplementary treatment of nanoparticles (before drying) with high hydrostatic pressure on the properties of the resulting carriers was also evaluated. The resulting nanoparticles displayed a mean size close to 150 nm and a folic acid content of around 25 ¿g per mg nanoparticle. From the in vitro release studies, it was observed that casein nanoparticles acted as gastro-resistant devices and, thus, folic acid was only released under simulated intestinal conditions. For the pharmacokinetic study, folic acid was orally administered to laboratory animals as a single dose of 1 mg/kg. Animals treated with folic acid-loaded casein nanoparticles displayed significantly higher serum levels than those observed in animals receiving an aqueous solution of the vitamin. As a consequence the oral bioavailability of folic acid when administered as casein nanoparticles was calculated to be around 52%, a 50% higher than the traditional aqueous solution. Unfortunately, the treatment of casein nanoparticles by high hydrostatic pressure modified neither the release profile of the vitamin nor its oral bioavailability.

During the past years there is a rising demand for improving the quality and nutritional value of foods that has encouraged the research and development of new food ingredients and products. Nevertheless, to date, many of the health claim applications evaluating EFSA have been rejected. Hence, it is critical for companies involved in the development of functional foods to be aware of the full flowchart needed for the scientific support of a health claim from the very beginning. This series of articles summarize the conclusions presented in July 2014 during the workshop INCOMES devoted to clarify methodologies for scientific support of health claims in foods/ingredients, in the framework of the XVI Reunión de la Sociedad Española de Nutrición, and are intended to be a practical tool, outlining the sections that an application for authorization of a health claim should contain.

The aim of this work was to prepare and evaluate the capability of zein nanoparticles for oral drug delivery. More particularly, in this work, the ability of these nanoparticles to improve the oral bioavailability of folic acid is reported. The nanoparticles were prepared by a desolvation process, followed by purification via ultrafiltration and drying in a spray-drier apparatus. The resulting nanoparticles displayed a mean size close to 200 nm with negative zeta potential and a payload of 54 ¿g folic acid per mg nanoparticle. From the in vitro release studies, it was observed that folic acid was only released from nanoparticles in simulated intestinal conditions. In vivo biodistribution studies, with radiolabelled or fluorescently marked nanoparticles, revealed that nanoparticles remained within the gut and were capable of interacting with the protective mucus layer of the jejunum. For the pharmacokinetic study, folic acid was orally administered to rats as a single dose of 1 mg/kg. The relatively oral bioavailability of folic acid, when encapsulated in zein nanoparticles, was around 70%: two-times higher than the value obtained with an aqueous solution of the vitamin. This fact might be explained by the mucoadhesive properties of these nanoparticles.

Resveratrol offers pleiotropic health benefits including a reported ability to inhibit lipopolysaccharide (LPS)-induced cytokine production. The aim of this work was to prepare, characterize, and evaluate a resveratrol nanoparticulate formulation based on zein. For this purpose, the oral bioavailability of the encapsulated polyphenol as well as its anti-inflammatory effects in a mouse model of endotoxic shock was studied. The resveratrol-loaded nanoparticles displayed a mean size of 307 +/- 3 nm, with a negative zeta potential (-51.1 +/- 1.55 mV), and a polyphenol loading of 80.2 +/- 3.26 mu g/mg. In vitro, the release of resveratrol from the nanoparticles was found to be pH independent and adjusted well to the Peppas-Sahlin kinetic model, suggesting a mechanism based on the combination of diffusion and erosion of the nanoparticle matrix. Pharmacokinetic studies demonstrated that zein-based nanoparticles provided high and prolonged plasma levels of the polyphenol for at least 48 h. The oral bioavailability of resveratrol when administered in these nanoparticles increased up to 50% (19.2-fold higher than for the control solution of the polyphenol). Furthermore, nanoparticles administered daily for 7 days at 15 mg/kg were able to diminish the endotoxic symptoms induced in mice by the intraperitoneal administration of LPS (i.e., hypothermia, piloerection, and stillness). In addition, serum tumor necrosis factor-alpha (TNF-alpha) levels were slightly lower (approximately 15%) than those observed in the control.

This paper evaluates the use of denaturing high performance liquid chromatography (DHPLC) technology for the discrimination of genetic differences in the 16S rRNA and alcohol dehydrogenase (AdhA) genes among bacterial species based on its efficiency and sensitivity to enable the detection and discrimination of different genetic sequences. In order to optimize DHPLC protocols for the analysis of 16S rRNA gene fragments amplified from bacteria, DNA isolated from 22 different strains representing main bacterial groups of interest in food microbiology was analyzed. While the use of 16S rRNA gene did not allow to difference two wild strains of Acetobacter malorum, this region revealed as useful to differentiate them from some pathogenic bacteria as Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Listeria innocua, Clostridium perfringens or Sthapylococcus aureus, from spoilage microorganisms as Xantomonas vesicatoria and Alicyclobacillus spp., and also from lactic acid bacteria as Lactobacillus plantarum, Lactobacillus casei, Lactobacillus sakei, Lactobacillus acidophilus, Streptococcus thermophilus and Lactococcus lactis that may suppose technological risk during vinegar production. The results demonstrate that 16S rRNA gene region is not adequate for the discrimination of the acetic acid bacteria (AAB) strains, so AdhA gene was selected to identify the two wild strains of Acetobacter malorum. Also 6 different reference strains of AAB were separated based on differences in AdhA gene region. DHPLC technology is able to discriminate between these two wild strains of A. malorum based on differences existing in the AdhA gene region. The data obtained indicate that the technique is capable of identifying most bacteria at species level and even at strain level with optimization of the protocols. This is of particular relevance in the case of AAB due to their poor recovery on culture media and difficulties in detection of viable but non cultivable cells.

eta-Carotene is a carotenoid usually applied in the food industry as a precursor of vitamin A or as a colourant. beta-Carotene is a labile compound easily degraded by light, heat and oxygen. Casein micelles were used as nanostructures to encapsulate, stabilise and protect beta-carotene from degradation during processing in the food industry. Self-assembly method was applied to re-assemble nanomicelles containing beta-carotene. The protective effect of the nanostructures against degradation during the most common industrial treatments (sterilisation, pasteurisation, high hydrostatic pressure and baking) was proven. Casein micelles protected beta-carotene from degradation during heat stabilisation, high pressure processing and the processes most commonly used in the food industry including baking. This opens new possibilities for introducing thermolabile ingredients in bakery products.

The objective of this work was to obtain and stabilize natural vitamins from red pepper by-products. The method of obtainment was supercritical carbon dioxide extraction, studying different parameters that affect the yield. The highest extraction yield was found at 60 degrees C, 24 MPa extraction, with no modifier added and 0.2-0.5 mm particle size. The recovered extract was a red-coloured oil. The extract was subsequently microencapsulated by spray-drying using gum arabic as wall material to avoid the degradation of vitamin over the storage time. The thermal stability of microcapsules was analysed by thermal gravimetric analysis (TGA), while size, shape and morphology of microcapsules were studied by scanning electron microscopy (SEM). The microcapsules containing pepper extract were particles of spherical shape with dents on the surface, the average size of these particles was 5.46 mu m. (C) 2012 Elsevier Ltd. All rights reserved.