Digestibility of Quinoa (Chenopodium quinoa Willd.) Protein Concentrate and Its Potential to Inhibit Lipid Peroxidation in the Zebrafish Larvae Model.

Quinoa protein concentrate (QPC) was extracted and digested under in vitro gastrointestinal conditions. The protein content of QPC was in the range between 52.40 and 65.01% depending on the assay used. Quinoa proteins were almost completely hydrolyzed by pepsin at pH of 1.2, 2.0, and 3.2. At high pH, only partial hydrolysis was observed. During the duodenal phase, no intact proteins were visible, indicating their susceptibility to the in vitro simulated digestive conditions. Zebrafish larvae model was used to evaluate the in vivo ability of gastrointestinal digests to inhibit lipid peroxidation. Gastric digestion at pH 1.2 showed the highest lipid peroxidation inhibition percentage (75.15%). The lipid peroxidation activity increased after the duodenal phase. The digest obtained at the end of the digestive process showed an inhibition percentage of 82.10%, comparable to that showed when using BHT as positive control (87.13%).

Short communication: Production of antihypertensive peptide HLPLP by enzymatic hydrolysis: optimization by response surface methodology.

This study evaluates the potential ability of proteolytic enzymes to release the antihypertensive peptide HLPLP, ß-casein f(134-138), from caseinate. Corolase PP (Röhm GmbH & Co. KG, Darmstadt, Germany) was found as the most appropriate enzyme to produce this peptide. The optimization of the main experimental variables involved in the process [concentration of Corolase PP, concentration of Peptidase 433P (Biocatalysts Ltd., Parc Nantgarw, UK), and the hydrolysis time on the HLPLP concentration, expressed as area of peak] were studied using a central composite face design. The optimum conditions to obtain the maximum concentration of HLPLP provided by the statistical program were a concentration of Corolase PP of 60 mg/g of protein and hydrolysis time of 24h. The use of the Peptidase 433P did not increase the amount of the active peptide. The obtained hydrolysate might be used as functional ingredient with antihypertensive properties.

Combined treatment for optic disc pit maculopathy secondary to glaucoma.

CASE REPORT: A 58-year-old man was referred to the retina specialist for evaluation of decreased vision in the left eye (LE). At the first visit, visual acuity was 0.9 in right eye (RE) and hands movement in LE, and the intraocular pressure (IOP) was 34 mmHg and 42 mmHg in right and left eye, respectively. Dilated funduscopic examination revealed papillary pallor, increased cup-to-disc ratio of the optic nerve in both eyes, and retinal posterior pole oedema in the LE. Optical coherence tomography (OCT) and fluorescein angiography assessment confirmed the diagnosis of a macular serous retinal detachment (RD) caused by an optic disc pit secondary to glaucoma. Combined surgical treatment with ExPress drainage device implantation, pars plana vitrectomy (PPV), and juxtapapillar laser endophotocoagulation was performed. The IOP returned to normal, as well as complete anatomical resolution of macular RD.

Combined Treatment for Optic Disc Pit Maculopathy Secondary to Glaucoma. / Tratamiento combinado de la maculopatía por foseta papilar secundaria a glaucoma.

CASE REPORT: A 58-year-old man was referred to the retina specialist for evaluation of decreased vision in the left eye (LE). At the first visit, visual acuity was 0.9 in right eye (RE) and hands movement in LE, and the intraocular pressure (IOP) was 34 mmHg and 42 mmHg in right and left eye, respectively. Dilated funduscopic examination revealed papillary pallor, increased cup-to-disc ratio of the optic nerve in both eyes, and retinal posterior pole edema in the LE. Optical coherence tomography (OCT) and fluorescein angiography assessment confirmed the diagnosis of a macular serous retinal detachment (RD) caused by an optic disc pit secondary to glaucoma. Combined surgical treatment with ExPress drainage device implantation, pars plana vitrectomy (PPV), and juxtapapillar laser endophotocoagulation was performed. IOP normalization was achieved as well as complete anatomical resolution of macular RD.

Towards a more efficient Hydrothermal Carbonization: Processing water recirculation under different conditions.

The use of Processing Water (PW) on the Hydrothermal Carbonization (HTC) of tunisian pine cones was investigated under different temperature (200 and 240 °C) and residence time conditions (3 and 20 h). Recirculating PW improved the HC (hydrochar) solid yield, without being detrimental to the carbon content of the HC. The heating value of the HCs, that with a single reaction already involved a rise of this parameter in the range 22.1-55.8% as compared to the raw material, was further increased up to 24.9-58.6% for cyclic runs. This was attributed to enhanced secondary char formation by reusing liquid, although this effect depended on the severity of previous HTC and was affected by both temperature and time. The HCs showed an increment on C and especially on N for cyclic runs. Also, thermal degradation peaks during HC TGA/DTA analyses showed a broader temperature range decomposition upon pyrolysis when PW was recirculated. The modifications of HC surface morphologies and functional groups was also investigated and associated to related reaction mechanisms.

Tryptic amaranth glutelin digests induce endothelial nitric oxide production through inhibition of ACE: antihypertensive role of amaranth peptides.

Amaranth seed proteins have a better balance of essential amino acids than cereals and legumes. In addition, the tryptic hydrolysis of amaranth proteins generates, among other peptides, angiotensin converting enzyme (ACE) inhibitory (ACEi) peptides. ACE converts angiotensin I (Ang I) into Ang II, but is also responsible for the degradation of bradykinin (BK). In contrast to Ang II, BK stimulates vasodilation modulated through endothelial nitric oxide (NO) production. The aim of the present study was to characterize the ACEi activity of amaranth trypsin-digested glutelins (TDGs) and their ability to induce endothelial NO production. An IC(50) value of 200microgml(-1) was measured for TDG inhibition of ACE. TDGs stimulated endothelial NO production in coronary endothelial cells (CEC) by 52% compared to control. The effects of TDGs were comparable to those of BK and Captopril, both used as positive controls of NO production. Consistent with these effects, TDGs induced, in a dose-dependent manner, endothelial NO-dependent vasodilation in isolated rat aortic rings. These results suggest that TDGs induce endothelial NO production and consequent vasodilation through their ACEi activity. Amaranth TDGs have a high potential as a nutraceutical food in prevention of cardiovascular diseases. Further molecular, cellular and physiological studies are currently under way and the results may contribute to a better understanding and control of cardiovascular disorders.

Beta-lactoglobulin as source of bioactive peptides.

Beta-lactoglobulin (beta-Lg) is currently an important source of biologically active peptides. These peptides are inactive within the sequence of the precursor protein, but they can be released by in vivo or in vitro enzymatic proteolysis. Once released, these peptides play important roles in the human health, including antihypertensive, antioxidant and antimicrobial activities as well as opioid-like features and ability to decrease the body-cholesterol levels. Bioactive peptides derived from beta-Lg are currently a point of intensive research. Their structure, biological significance and mechanism of action are briefly presented and discussed in this review.

Protein degradation and peptide release from milk proteins in human jejunum. Comparison with in vitro gastrointestinal simulation.

Human jejunal digests after oral ingestion of casein and whey protein were collected by a nasogastric tube and protein degradation and peptide release was compared with that found in the digests of the same substrates using a standardised protocol. No intact casein was detected in the jejunal nor in the in vitro samples taken during the intestinal phase, while ß-lactoglobulin was found in one hour-jejunal samples in agreement with the in vitro digestion. In vivo and in vitro digests showed comparable peptide profiles and high number of common sequences. A selective precipitation step was used to strengthen the identification of phosphorylated peptides. Most of the sequences found in jejunum, some of them not previously described, were also identified in the simulated digests. Common resistant regions to digestion were identified, revealing that the in vitro protocol constitutes a good approximation to the physiological gastrointestinal digestion of milk proteins.

Conversion of tomato-peel waste into solid fuel by hydrothermal carbonization: Influence of the processing variables.

In this work, the influence of the variables temperature, residence time, and biomass/water ratio on the hydrothermal carbonization (HTC) of tomato peel was investigated. The implementation of a Design of Experiments - Response Surface Methodology approach allowed to identify the importance of each variable, as well as their interactions, in both the reactivity (solid yield) and energy densification (increase in higher heating value). The HTC residence time and specially temperature had a major effect on the process, increasing the solid yield and promoting energy densification. Ratio had a minor effect although under certain temperature and time conditions, it was a decisive parameter. Solid yields in the range 27.6% and 87.7% with corresponding high heating values 23.6-34.6 MJ kg(-1) were obtained. From the statistical processing of the experimental data obtained pseudo-second order models were developed. It was proven that these approaches envisaged the hydrochar final characteristics successfully. From the elemental analysis and the FTIR spectra, it was possible to investigate the HTC pathway, which was defined as a combination of several processes; considering dehydration and decarboxylation reactions and especially lignin depolimerization reactions, which lead to the formation of monomeric radicals. Moreover, the surface morphology of selected hydrochars by Scanning Electron Microscopy (SEM) showed the original structure scaffold, with minor changes between hydrochars prepared under different conditions.

Homogeneous Diffusion Solid Model as a Realistic Approach to Describe Adsorption onto Materials with Different Geometries.

In this work, the adsorption kinetics of p-nitrophenol (PNP) onto several commercial activated carbons (ACs) with different textural and geometrical characteristics was studied. For this aim, a homogeneous diffusion solid model (HDSM) was used, which does take the adsorbent shape into account. The HDSM was solved by means of the finite element method (FEM) using the commercial software COMSOL. The different kinetic patterns observed in the experiments carried out can be described by the developed model, which shows that the sharp drop of adsorption rate observed in some samples is caused by the formation of a concentration wave. The model allows one to visualize the changes in concentration taking place in both liquid and solid phases, which enables us to link the kinetic behaviour with the main features of the carbon samples.

Production of Cost-Effective Mesoporous Materials from Prawn Shell Hydrocarbonization.

In this work, prawn shell was studied as raw material for the production of mesoporous adsorbents via hydrocarbonization, studying the effect of temperature and time on the process reactivity and final characteristics of the hydrochars. By suitable characterization technique analyses (N2 adsorption at 77 K, SEM observation, ultimate analysis, surface composition), the materials were examined. It was found that in both cases mesoporous materials with low values of S BET due to the presence of CaCO3 on the material structure. In order to provide a potential application for these materials, the adsorption behaviour of hydrochars (HCs) as well as that of pristine prawn shells and ashes from prawn shell combustion was studied for the first time with the model compound p-nitrophenol (PNP). The results indicated that HC treatment was beneficial and enhanced adsorption performance, especially at high values of equilibrium concentration, attaining adsorption capacities up to 1.6 mg g(-1).

Angiotensin-converting enzyme inhibitory activity of peptides derived from caprine kefir.

In this study, a potent angiotensin-converting enzyme (ACE)-inhibitory activity was found in a commercial kefir made from caprine milk. The low molecular mass peptides released from caseins during fermentation were mainly responsible for this activity. Sixteen peptides were identified by HPLC-tandem mass spectrometry. Two of these peptides, with sequences PYVRYL and LVYPFTGPIPN, showed potent ACE-inhibitory properties. The impact of gastrointestinal digestion on ACE-inhibitory activity of kefir peptides was also evaluated. Some of these peptides were resistant to the incubation with pepsin followed by hydrolysis with Corolase PP. The ACE-inhibitory activity after simulated digestion was similar to or slightly lower than unhydrolyzed peptides, except for peptide beta-casein f(47-52) (DKIHPF), which exhibited an activity 8 times greater after hydrolysis.

Development and characterization of activated hydrochars from orange peels as potential adsorbents for emerging organic contaminants.

Activated hydrochars obtained from the hydrothermal carbonization of orange peels (Citrus sinensis) followed by various thermochemical processing were assessed as adsorbents for emerging contaminants in water. Thermal activation under flows of CO2 or air as well as chemical activation with phosphoric acid were applied to the hydrochars. Their characteristics were analyzed and related to their ability to uptake three pharmaceuticals (diclofenac sodium, salicylic acid and flurbiprofen) considered as emerging contaminants. The hydrothermal carbonization and subsequent activations promoted substantial chemical transformations which affected the surface properties of the activated hydrochars; they exhibited specific surface areas ranging from 300 to ∼620 m(2)/g. Morphological characterization showed the development of coral-like microspheres dominating the surface of most hydrochars. Their ability to adsorb the three pharmaceuticals selected was found largely dependent on whether the molecules were ionized or in their neutral form and on the porosity developed by the new adsorbents.

Molecular cloning, sequencing and expression of a serine proteinase inhibitor gene from Toxoplasma gondii.

A cDNA clone from a Toxoplasma gondii tachyzoite cDNA library encoding a serine proteinase inhibitor (serpin) was isolated. The 1376 bp cDNA sequence encodes a 294 amino acid protein with a putative signal peptide of 23 amino acids resulting in a mature protein with a predicted mass of 30,190 Da and a pI of 4.86. This protein has internal sequence similarity of residues 30-66, 114-150, 181-217 and 247-283 indicating a four-domain structure. The four domains exhibit high identity to serine proteinase inhibitors belonging to the non-classical Kazal-type family. The gene is single copy in the tachyzoite haploid genome of RH strain and was amplified by polymerase chain reaction (PCR). Several introns were identified. The sequence encoding the mature protein was amplified by PCR, cloned into the pQE30 vector and expressed in Escherichia coli. Specific antiserum generated against the recombinant protein was used in immunoblot assay and two bands of 38 and 42 kDa were detected in a whole parasite homogenate. The recombinant protein showed trypsin-inhibitory activity, one of the two potential specificities. We discuss the possible roles that T. gondii serpin(s) may play in the survival of the tachyzoites in the host.

Pharmacokinetics of noreximide in the beagle dog.

The psychopharmacologically active drug noreximide was administered in a crossover design to beagle dogs intravenously, and perorally in form of a solution and as capsule. The dosage forms were prepared from 14C-labeled noreximide and cold material. The total radioactivity and that of the metabolite were determined in plasma after TLC separation. The mean half-life of the parent compound is about 4.5 hours after I.V. and 9.5 hours after P.O. administration. The apparent volume of distribution is about 20 l/kg, and the total clearance about 44 l/h after I.V. and about 29 l/h after P.O. dosing. The absolute bioavailability is about 50%. The drug is completely absorbed but undergoes extensive first-pass metabolism. The main metabolite, noreximide-epoxide has an elimination half-life of about 20 hours and an apparent volume of distribution identical to that of the parent compound. The peak metabolite concentrations occur about 10 hours after dosing.

Chemopreventive properties of Peptide Lunasin: a review.

Cancer has become one the most common causes of death in developed countries and has been defined as the medical challenge of our times. Accumulating evidence support the notion that prevention can be a major component of cancer control. Chemoprevention, a relatively new and promising strategy to prevent cancer, is defined as the use of natural and/or synthetic substances to block, reverse, or retard the process of carcinogenesis. Plant-based foods, containing significant amounts of bioactive phytochemicals, may provide desiderable health benefits beyond basic nutrition to reduce the process of cancer. In the last few years, proteins and peptides have become one group of nutraceuticals that show potential results in preventing the different stages of cancer including initiation, promotion, and progression. Lunasin is a 43- amino acid peptide identified in soybean and other plants whose anti-carcinogenic activity has been demonstrated both in in vitro and in vivo assays. Moreover, this peptide has been found to exert anti-inflammatory and antioxidant properties that could contribute to its chemopreventive effects. Lunasin's bioactivity and its molecular mechanism(s) of actions are summarized in this review.

Echinococcus granulosus: cloning and characterization of a tandemly repeated DNA element.

A repetitive DNA element from the genome of the cestode Echinococcus granulosus has been cloned and sequenced. The 186-base-pair repeating units are arranged in direct tandem, probably clustered in the parasite genome. The estimated copy number of the repeat is 11,500 and represents between 2 and 3% of the parasite genome. The repetitive sequence is specific for Echinococcus since it does not cross-hybridize with either DNA of other cestode species or pig and dog DNA. The repetitive element is capable of detecting between 250 and 500 pg of E. granulosus DNA by dot blot assay.