Functional and bioactive properties of collagen and gelatin from alternative sources: A review

The rising interest in the valorisation of industrial by-products is one of the main reasons why exploring different species and optimizing the extracting conditions of collagen and gelatin has attracted the attention of researchers in the last decade. The most abundant sources of gelatin are pig skin, bovine hide and, pork and cattle bones, however, the industrial use of collagen or gelatin obtained from non-mammalian species is growing in importance. The classical food, photographic, cosmetic and pharmaceutical application of gelatin is based mainly on its gel-forming properties. Recently, and especially in the food industry, an increasing number of new applications have been found for gelatin in products such as emulsifiers, foaming agents, colloid stabilizers, biodegradable film-forming materials and micro-encapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones. In the last decade, a large number of studies have dealt with the enzymatic hydrolysis of collagen or gelatin for the production of bioactive peptides. Besides exploring diverse types of bioactivities, of an antimicrobial, antioxidant or antihypertensive nature, studies have also focused on the effect of oral intake in both animal and human models, revealing the excellent absorption and metabolism of Hyp-containing peptides. The present work is a compilation of recent information on collagen and gelatin extraction from new sources, as well as new processing conditions and potential novel or improved applications, many of which are largely based on induced cross-linking, blending with other biopolymers or enzymatic hydrolysis. © 2011 Elsevier Ltd.Peer Reviewe

Functional and bioactive properties of collagen and gelatin from alternative sources: A review

The rising interest in the valorisation of industrial by-products is one of the main reasons why exploring different species and optimizing the extracting conditions of collagen and gelatin has attracted the attention of researchers in the last decade. The most abundant sources of gelatin are pig skin, bovine hide and, pork and cattle bones, however, the industrial use of collagen or gelatin obtained from non-mammalian species is growing in importance. The classical food, photographic, cosmetic and pharmaceutical application of gelatin is based mainly on its gel-forming properties. Recently, and especially in the food industry, an increasing number of new applications have been found for gelatin in products such as emulsifiers, foaming agents, colloid stabilizers, biodegradable film-forming materials and micro-encapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones. In the last decade, a large number of studies have dealt with the enzymatic hydrolysis of collagen or gelatin for the production of bioactive peptides. Besides exploring diverse types of bioactivities, of an antimicrobial, antioxidant or antihypertensive nature, studies have also focused on the effect of oral intake in both animal and human models, revealing the excellent absorption and metabolism of Hyp-containing peptides. The present work is a compilation of recent information on collagen and gelatin extraction from new sources, as well as new processing conditions and potential novel or improved applications, many of which are largely based on induced cross-linking, blending with other biopolymers or enzymatic hydrolysis. © 2011 Elsevier Ltd.Peer Reviewe

Quality of thawed deepwater pink shrimp (Parapenaeus longirostris) treated with melanosis-inhibiting formulations during chilled storage

This work investigates how the treatment of thawed deepwater pink shrimp (Parapenaeus longirostris) with several melanosis-inhibiting formulations, affects the quality of the shrimp during chilled storage. Formulations were as follows: a formulation containing 4-hexylresorcinol (0.1 and 0.05%), in combination with organic acids and chelating agents, a commercial formula based on sulphites, and a mixture of gluconic acid and commercial sulphites. No noticeable differences were observed for both trimethylamine and total volatile bases during chilled storage. pH evolution was irrespective of the treatment condition. Microbial load enlarged after the sixth day of chilled storage. Higher total bacteria counts were associated with the control and sulphite treatment conditions, while lactic acid bacteria growth seemed to be favoured under formulations based on 4-hexylresorcinol. The appearance of melanosis occurred more rapidly in control shrimp or in shrimp treated with commercial sulphites. 4-hexylresorcinol formulations preserved the quality of thawed shrimp and could replace traditional sulphites. © 2007 The Authors. Journal compilation 2007 Institute of Food Science and Technology Trust Fund.Peer Reviewe

Antioxidant and antimicrobial peptide fractions from squid and tuna skin gelatin

27 páginas, 4 figuras, 4 tablas.Gelatin extracted from tuna skins and giant squid tunics were hydrolysed with Alcalase at 50ºC for 3h. Two peptide fractions (1-10K and ≤1K) were obtained from each gelatin hydrolysate by subjecting them to centrifugal ultrafiltration using successively a 10 kDa and a 1 kDa membrane. The peptide fractions were characterized in terms of amino acid composition and Fourier transform infrared (FTIR) spectroscopy. Antioxidant properties were tested according to the Ferric Reducing Antioxidant Power (FRAP) assay and the radical scavenging capacity (ABTS) assay. A disk diffusion test was performed to test antimicrobial action against a panel of Gram-positive and Gramnegative pathogenic and fish spoilage-associated microorganisms. Although antioxidant and antimicrobial properties could be detected in all tested peptide fractions, the lowermost molecular weight fraction from squid hydrolysate presented the highest reducing and radical scavenging capacities, whereas microbial growth inhibition was found to be specifically related to the type of microorganism.This study was supported by the Spanish “Ministerio de Educación y Ciencia” (project AGL2005-02380/ALI and AGL2008-02135/ALI).Peer reviewe

Oral health-related quality of life after dental treatment in patients with intellectual disability

The influence of dental treatment on oral health-related quality of life (OHRQOL) has rarely been evaluated in patients with intellectual disability (ID) through validated questionnaires. The aim of this study was to estimate the changes on OHRQOL in patients with ID after the implementation of an institutional dental treatment program under general anesthesia using the Franciscan Hospital for Children Oral Health-Related Quality of Life questionnaire (FHCOHRQOL-Q). A prospective longitudinal study was conducted on 85 patients (mean age=24.85 years) classified according to DSM-V whose parents/caregivers completed the FHC-OHRQOL-Q. We analyzed the changes in the questionnaire?s overall score and its dimensions from pre-treatment to 12-months of follow-up, considering effect sizes and minimal important differences estimated by the standard measurement error. The impact of clinical and therapeutic factors was evaluated using univariate and multiple linear regression analysis (p<0.05). Significant improvement of OHRQOL was found after dental treatment in oral symptoms (p0.001), daily life problems (p=0.018), parent?s perceptions (p=0.013) and FHCOHRQOL-Q´s overall score (p=0.001). OHRQOL changes exhibited an intermediate magnitude (0.38-0.21) as estimated by effect sizes. Changes in oral symptoms showed positive correlation with DMFT index (r=0.375, p=0.002), decayed teeth (r=0.244, p=0.036), dental extractions (r=0.424, p<0.001) and number of treatments (r=0.255, p=0.019). The improvement was greater in patients with 4 decayed teeth (p=0.049) and undergoing 2 dental extractions (p=0.002). Multiple regression analysis demonstrated that dental extractions (p<0.001) and DMFT index (p=0.028) were significantly related to oral symptom improvement. Dental treatment under general anesthesia showed a positive effect on the overall FHC-OHRQOL-Q score and most of its dimensions. At 12-months of follow-up, the improvement of oral symptoms was significantly associated with DMFT index, decayed teeth, dental extractions and number of treatments. In our clinical setting, the implementation of a dental treatment program enhanced the OHRQOL of patients with ID

Structure, Functionality, and Active Release of Nanoclay–Soy Protein Films Affected by Clove Essential Oil

Nowadays, there is a pronounced interest in the potential use of biopolymer/layered silicate systems as active food packaging. This manuscript studied the effect of clove essential oil addition to soy protein–montmorillonite (MMT) films on the material’s structure, functionality, and active release. Active nanocomposite films were prepared by casting from aqueous dispersions containing soy protein isolates (SPI), glycerol, different concentrations of MMT and clove essential oil. Besides the important antioxidants and antimicrobial properties provided to nanocomposite films, the addition of clove essential oil exerted a plasticizing effect, which was verified in a decrease in the tensile strength and elastic modulus (up to 50 and 75 %, respectively) and an increase of the water content of films (up to 20 %). But the nanoclay caused a further strengthening effect in films containing CEO. While nanocomposite films containing 10 g MMT/100 g SPI reached an increase of 105 and 200 % in tensile strength and Young’s modulus, respectively, and a decrease of 340 % in their elongation at break, those that also contained CEO reached higher variations (230, 345, and 290 %, respectively). Clove essential oil presence also favored the exfoliation of montmorillonite into the soy protein matrix, while the nanoclay seemed to promote the release of active compounds, occasionally modifying the antimicrobial activity of films as well as the release of some of its Si and Al ions after being in contact with water (at least twice).Centro de Investigación y Desarrollo en Criotecnología de Alimento

Rhodamine-based sensor for real-time imaging of mitochondrial ATP in living fibroblasts

Mitochondria are essential for the production and maintenance of ATP in the eukaryotic cell. To image and monitor intracellular ATP level without cell breakage, biological and chemical sensors were developed in the last years. Here, we have internalized a rhodamine-based sensor RSL+ into living cells and monitored the mitochondrial ATP levels in cultured mouse embryonic fibroblasts. To evaluate the robustness of the sensor we imaged the changes of the mitochondrial ATP levels under non-physiological conditions upon incubation with FCCP, oligomycin, azide, deoxyglucose or phosphoenolpyruvate; all compounds that interfere with ATP homeostasis of the cell. The ATP sensor allowed us to determine the mitochondrial ATP levels in human skin fibroblasts where we observe a similar amount of ATP compared to mouse embryonic fibroblasts. We propose the RSL+ to be a valuable tool for the assessment of mitochondrial dysfunction in human cells derived from mitochondrial OXPHOS patients and for basic studies on bioenergetics metabolism

How rotating ATP synthases can modulate membrane structure

F1Fo-ATP synthase (ATP synthase) is a central membrane protein that synthetizes most of the ATP in the cell through a rotational movement driven by a proton gradient across the hosting membrane. In mitochondria, ATP synthases can form dimers through specific interactions between some subunits of the protein. The dimeric form of ATP synthase provides the protein with a spontaneous curvature that sustain their arrangement at the rim of the high-curvature edges of mitochondrial membrane (cristae). Also, a direct interaction with cardiolipin, a lipid present in the inner mitochondrial membrane, induces the dimerization of ATP synthase molecules along cristae. The deletion of those biochemical interactions abolishes the protein dimerization producing an altered mitochondrial function and morphology. Mechanically, membrane bending is one of the key deformation modes by which mitochondrial membranes can be shaped. In particular, bending rigidity and spontaneous curvature are important physical factors for membrane remodelling. Here, we discuss a complementary mechanism whereby the rotatory movement of the ATP synthase might modify the mechanical properties of lipid bilayers and contribute to the formation and regulation of the membrane invaginations

Transport Phenomena in Films and Coatings Including Their Mathematical Modeling

In the present chapter, two examples related to transport phenomena in films and coatings are discussed. One of them represents the heat and mass transfer process in fried foods that were covered with an edible coating based on methylcellulose (MC). This is an alternative to reduce oil uptake (OU) in fried foods due to its lipid-barrier properties. The following aspects are discussed: (1) mathematical modeling of heat and moisture transfer during the deep-fat frying of food, (2) experimental validation of the mathematical model with regard to the temperature profiles and the water losses from the food product, (3) analysis of the relationship between the OU measurements and microstructural changes developed, and (4) performance of applying an edible coating based on MC on a food model dough system. The mathematical model of the frying process based on the numerical solution of the heat and mass transfer differential equations under unsteady-state conditions was proposed and solved. It allows simulating satisfactorily the experimental data of temperature and water content during the different frying stages. OU was also linearly correlated with water loss at the initial frying stage. A simple equation for OU as a function of frying times was proposed, considering the microstructural changes developed during the frying process. The presence of MC coating reduced the OU, modifying the wetting properties and also becoming a mechanical barrier to the oil. The second example represents the mathematical modeling of potassium sorbate release from a starch biodegradable active film to a model food system represented by a gel in contact with the active film. Mass transfer partial differential equations in nonstationary conditions were numerically solved using the finite element method. The model assumes a constant initial mass of antimicrobial in the active film that diffuses through the film penetrating in the food system. The numerical solution allowed the determination of the diffusion coefficients of the antimicrobial agent in both, the film and the gel. Concentration profiles were simulated to predict the time period in which the antimicrobial concentration can be maintained above the critical inhibitory concentration in the packaged food. Experimental data of sorbate diffusion from active films and from a liquid solution to the semisolid medium were compared with the predicted concentration profiles. The model allows the simulation of nonstationary diffusion of different additives incorporated to polymeric matrixes, taking into account the preservative concentration in the film and the dimensions of the semisolid food system.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Immunosuppression-independent role of regulatory T cells against hypertension-driven renal dysfunctions

Hypertension-associated cardiorenal diseases represent one of the heaviest burdens for current health systems. In addition to hemodynamic damage, recent results have revealed that hematopoietic cells contribute to the development of these diseases by generating proinflammatory and profibrotic environments in the heart and kidney. However, the cell subtypes involved remain poorly characterized. Here we report that CD39+ regulatory T (TREG) cells utilize an immunosuppression-independent mechanism to counteract renal and possibly cardiac damage during angiotensin II (AngII)-dependent hypertension. This mechanism relies on the direct apoptosis of tissue-resident neutrophils by the ecto-ATP diphosphohydrolase activity of CD39. In agreement with this, experimental and genetic alterations in TREG/TH cell ratios have a direct impact on tissue-resident neutrophil numbers, cardiomyocyte hypertrophy, cardiorenal fibrosis, and, to a lesser extent, arterial pressure elevation during AngII-driven hypertension. These results indicate that TREG cells constitute a first protective barrier against hypertension-driven tissue fibrosis and, in addition, suggest new therapeutic avenues to prevent hypertension-linked cardiorenal diseases.This work has been supported by grants from the Castilla-León Autonomous Government (CSI101U13), the Spanish Ministry of Economy and Competitiveness (SAF2012-31371, RD12/0036/0002), Worldwide Cancer Research, the Solórzano Foundation, and the Ramón Areces Foundation to X.R.B. P.M. is funded by the Spanish Ministry of Economy and Competitiveness (SAF2011-27330). S.F., M.M.-M., J.R.-V., and A.M.-M. were supported by the Spanish Ministry of Economy and Competitiveness through BES-2010-031386, CSIC JAE-Doc, Juan de la Cierva, and BES-2009-016103 contracts, respectively. Spanish government-sponsored funding to X.R.B. is partially supported by the European Regional Development Fund.Peer Reviewe