Chitosan-Based Sustained Expression of Sterol Regulatory Element-Binding Protein 1a Stimulates Hepatic Glucose Oxidation and Growth in Sparus aurata.

The administration of a single dose of chitosan nanoparticles driving the expression of sterol regulatory element-binding protein 1a (SREBP1a) was recently associated with the enhanced conversion of carbohydrates into lipids. To address the effects of the long-lasting expression of SREBP1a on the growth and liver intermediary metabolism of carnivorous fish, chitosan-tripolyphosphate (TPP) nanoparticles complexed with a plasmid expressing the N terminal active domain of hamster SREBP1a (pSG5-SREBP1a) were injected intraperitoneally every 4 weeks (three doses in total) to gilthead sea bream (Sparus aurata) fed high-protein-low-carbohydrate and low-protein-high-carbohydrate diets. Following 70 days of treatment, chitosan-TPP-pSG5-SREBP1a nanoparticles led to the sustained upregulation of SREBP1a in the liver of S. aurata. Independently of the diet, SREBP1a overexpression significantly increased their weight gain, specific growth rate, and protein efficiency ratio but decreased their feed conversion ratio. In agreement with an improved conversion of dietary carbohydrates into lipids, SREBP1a expression increased serum triglycerides and cholesterol as well as hepatic glucose oxidation via glycolysis and the pentose phosphate pathway, while not affecting gluconeogenesis and transamination. Our findings support that the periodical administration of chitosan-TPP-DNA nanoparticles to overexpress SREBP1a in the liver enhanced the growth performance of S. aurata through a mechanism that enabled protein sparing by enhancing dietary carbohydrate metabolisation.

Antibacterial and Antiproliferative Activities of Azadirachta indica Leaf Extract and Its Effect on Oil-in-Water Food Emulsion Stability.

The present study aims to identify and quantify the phenolic compounds of Azadirachta indica leaf extract using HPLC-MS and to evaluate the antioxidant, antibacterial (against different Gram-positive and negative bacteria) and in vitro anti-proliferative activities of this extract (against breast, human liver and cervix adenocarcinoma-derived cells). The application of this extract as a natural antioxidant for food preservation was also tested on oil-in-water food emulsions for the first time in the present work in order to determine the use of Azadirachta indica leaves as a natural additive to preserve the food against lipid oxidation and rancidity. The results obtained revealed that 50%-aqueous ethanol leaf extract showed the best extraction yield (25.14%), which was characterized by a high content in phenolic compounds and strong antioxidant activity. Moreover, this leaf extract inhibited the growth of the bacterial strains tested (Staphylococcus aureus, Escherichia coli, Salmonella paratyphi and Micrococcus luteus) and showed better anti-proliferative activity against breast and cervix adenocarcinoma-derived cells than human liver cancer cells after 48 h of treatment. Additionally, Azadirachta indica leaf extract showed almost similar effects as gallic acid solutions (0.25% and 0.5%) in preserving the oxidation of oil-in-water food emulsions and prevented the formation of secondary oxidation products (malondialdehyde) as well. The results obtained suggested that extracts of Azadirachta indica leaves are a potential source of antioxidant and antibacterial compounds and pointed to the potential of these natural extracts as therapeutic agents.

Phenolic Profile, EPR Determination, and Antiproliferative Activity against Human Cancer Cell Lines of Anthyllis vulneraria Extracts.

In the current work, the leaf and flower extracts of Anthyllis vulneraria were evaluated for their chemical characterization using HPLC-MS and for their radical scavenging capacity toward methoxy radicals produced by a Fenton-type reaction using an electron paramagnetic resonance (EPR) spectroscopy assay. The in vitro antiproliferative activity of these extracts against several human-derived cancer cells (breast: MCF-7; cervical: HeLa; hepatocellular: HepG2) was also evaluated. The results showed that the Anthyllis vulneraria leaf extract was characterized by 17 different phenolic compounds, among which phenolic acids were the most abundant, while its flower extract exhibited higher contents of flavonoids. Furthermore, Anthyllis vulneraria extracts demonstrated a potent radical scavenging activity against methoxy radicals. Both extracts also significantly reduced the viability of the different cancer cell lines. The results of the current study suggested that Anthyllis vulneraria extracts are a promising source of antioxidant compounds with health benefits and pointed to their potential use for treating cancer and developing novel therapeutic agents.

Formation of a stable biradical triplet state cation versus a closed shell singlet state cation by oxidation of adducts of 3,6-dimethoxycarbazole and polychlorotriphenylmethyl radicals.

We report an experimental and theoretical study of two stable radical adducts of the triphenylmethyl series, 1 and 2, whose composition and molecular structure are distinguished by the content and position of chlorine atoms in phenyls. The electrochemical study through cyclic voltammetry of these open layer species shows the existence of two reversible processes, related to reduction and oxidation, to stable charged species. The chemical oxidation of both radical adducts gives rise to stable cations, whose fundamental state has a biradical triplet electronic structure or a closed shell singlet character, depending on the electronic conjugation between the donor and acceptor electron moieties. The presence of chlorines adjacent to the nitrogen in 1 breaks the conjugation between both halves, facilitating the formation of a triplet electronic state of the cation, while the absence of chlorines in these positions in 2 facilitates partial conjugation and stabilizes the closed shell singlet electronic state of the cation.

Effects of Pecan Nut (Carya illinoiensis) and Roselle Flower (Hibiscus sabdariffa) as Antioxidant and Antimicrobial Agents for Sardines (Sardina pilchardus).

The effects of pecan nut (Carya illinoinensis) and roselle flower (Hibiscus sabdariffa) as antioxidant and antimicrobial agents on shelf life extension of sardines (Sardina pilchardus) were evaluated over a period of 5 days at 7 ± 1 °C. Treatments consisted of the addition of 5% and 10% w/w pecan nut, 5% w/w roselle flower and a combination of 5% of each. Physicochemical (lipid oxidation, fatty acids, hexanal and biogenic amines), sensory and microbiological characteristics of fish samples were periodically analyzed. All treatments effectively improved physicochemical quality parameters, with 10% w/w pecan nut having the highest effectiveness. The presence of roselle flower reduced microbial growth. Our findings suggest that addition of a natural preservative combining pecan nut and roselle flower may extend the shelf life of fresh sardines during chilled storage while maintaining quality indexes.

Radical Scavenging and Antioxidant Activity of Anthyllis Vulneraria Leaves and Flowers.

The main targets of this work were to determine the phenolic content of Anthyllis vulneraria (A. vulneraria) leaves and flowers and to evaluate their antioxidant activity. Total polyphenols and flavonoid content (TPC and TFC, respectively) were determined. Antioxidant capacity was evaluated by the Ferric Reducing Antioxidant Power (FRAP), the Oxygen Radical Absorbance Capacity (ORAC), the Trolox Equivalent Antioxidant Capacity (TEAC) and the diphenyl picrylhydrazyl (DPPH) assays, and by the analysis of primary and secondary oxidation products in oil-in-water emulsions and in raw beef patties during storage. The results revealed that the flowers of the A. vulneraria contained the highest content of total polyphenols and flavonoids and extracts from these tissues exhibited the strongest antioxidant activity, as they were more effective at retarding lipid oxidation in oil-in-water emulsions and raw beef patties than extracts from the leaves which had a potent antioxidant effect only at the beginning of the oxidation process. The results of this study allowed us to obtain a deep knowledge about the properties of A. vulneraria and confirmed the possibility of using its biologically active extracts in the food, cosmetic and pharmaceutical industries.

Continuous or Batch Solid-Liquid Extraction of Antioxidant Compounds from Seeds of Sterculia apetala Plant and Kinetic Release Study.

This work has been intended to investigate the antioxidant properties of compounds extracted from seeds of Sterculia apetala (a plant from Central America) in order to add further results to the relatively poor existing literature on the beneficial properties of this plant. Different extraction methodologies were used such as batch or continuous extraction conditions using water or ethanol 50% as solvents. The kinetic study has allowed estimation of the effective diffusion coefficients in a continuous solid-liquid extraction, highlighting the strict dependence of the diffusion rate and temperature and kind of solvent, showing the highest diffusion rate with ethanol 50% at 60 °C. The comparison between different techniques and two solvents led to the selection of water as the best extraction solvent while batch mechanically-agitated extraction was the most efficient mode, with the benefits of use of an environmental-friendly solvent and reduction in process time to achieve a high amount of extracted phenolic compounds. The analysis techniques used were ABTS and Folin-Ciocalteau methods to investigate the antioxidant activity and quantify the Total Phenolic Content (TPC) respectively. Also, different fatty acids were extracted from Sterculia apetala seeds and analysed by Gas Chromatography in order to quantify other interesting chemical species besides antioxidants.

Avocado Seed: A Comparative Study of Antioxidant Content and Capacity in Protecting Oil Models from Oxidation.

Increasingly, consumers want products containing little or no synthetic compounds. Avocado seeds, which are a residue of the food industry, could be used to obtain extracts with high antioxidant power. In the present study, the most popular radical scavenging methods are presented, establishing a comparison between them, besides working with two different extractions: pure methanol and ethanol⁻water (50:50 v/v). The radical scavenging assay methods ORAC and ABTS were performed, as well as a novel method: the reaction to methoxy radical, as determined by electron paramagnetic resonance (EPR). Peroxide value and thiobarbituric acid reactive compounds (TBARs) were used to monitor the oxidation of avocado seed oil, as well as the power of the avocado seed extract (ASE) to delay oil oxidation by oxidation induction time (OIT) and measured by differential scanning calorimetry (DSC). Radical scavenging methods have values between 1310⁻263 µmol TE/g of mass dissolved for ORAC and ABTS, respectively. The individual contribution of each of the compounds present in the extract was analyzed. The sum of all of them contributed up to 84% of the total radical scavenging activity. The concentration of 0.75% ASE causes a delay in the oxidation that is close to 80%, as measured by OIT. This implies that avocado seed residue may have a use as a natural antioxidant source, providing added value to organic waste.

A transcriptomic approach to study the effect of long-term starvation and diet composition on the expression of mitochondrial oxidative phosphorylation genes in gilthead sea bream (Sparus aurata).

BACKGROUND: The impact of nutritional status and diet composition on mitochondrial oxidative phosphorylation (OXPHOS) in fish remains largely unknown. To identify biomarkers of interest in nutritional studies, herein we obtained a deep-coverage transcriptome by 454 pyrosequencing of liver and skeletal muscle cDNA normalised libraries from long-term starved gilthead sea bream (Sparus aurata) and fish fed different diets. RESULTS: After clean-up of high-throughput deep sequencing reads, 699,991 and 555,031 high-quality reads allowed de novo assembly of liver and skeletal muscle sequences, respectively (average length: 374 and 441 bp; total megabases: 262 and 245 Mbp). An additional incremental assembly was completed by integrating data from both tissues (hybrid assembly). Assembly of hybrid, liver and skeletal muscle transcriptomes yielded, respectively, 19,530, 11,545 and 10,599 isotigs (average length: 1330, 1208 and 1390 bp, respectively) that were grouped into 15,954, 10,033 and 9189 isogroups. Following annotation, hybrid transcriptomic data were used to construct an oligonucleotide microarray to analyse nutritional regulation of the expression of 129 genes involved in OXPHOS in S. aurata. Starvation upregulated cytochrome c oxidase components and other key OXPHOS genes in the liver, which exhibited higher sensitive to food deprivation than the skeletal muscle. However, diet composition affected OXPHOS in the skeletal muscle to a greater extent than in the liver: most of genes upregulated under starvation presented higher expression among fish fed a high carbohydrate/low protein diet. CONCLUSIONS: Our findings indicate that the expression of coenzyme Q-binding protein (COQ10), cytochrome c oxidase subunit 6A2 (COX6A2) and ADP/ATP translocase 3 (SLC25A6) in the liver, and cytochrome c oxidase subunit 5B isoform 1 (COX5B1) in the liver and the skeletal muscle, are sensitive markers of the nutritional condition that may be relevant to assess the effect of changes in the feeding regime and diet composition on fish farming.

Evaluation of the antioxidant activity of Betula pendula leaves extract and its effects on model foods.

CONTEXT: Betula pendula Roth (Betulaceae) exhibits many pharmacological activities in humans including anticancer, antibacterial, and antiviral effects. However, the antioxidant activity of BP towards lipid degradation has not been fully determined. OBJECTIVE: The BP ethanol and methanol extracts were evaluated to determine antioxidant activity by an in vitro method and lyophilized extract of BP was added to beef patties to study oxidative stability. MATERIALS AND METHODS: Antioxidant activities of extracts of BP were determined by measuring scavenging radical activity against methoxy radical generated by Fenton reaction 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (TEAC) radical cation, the oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP) assays. The lipid deterioration in beef patties containing 0.1% and 0.3% (w/w) of lyophilized extract of BP stored in 80:20 (v/v) O2:CO2 modified atmosphere (MAP) at 4 °C for 10 days was determined using thiobarbituric acid reacting substances (TBARS), % metmyoglobin and colour value. RESULTS: The BP methanol extract revealed the presence of catechin, myricetin, quercetin, naringenin, and p-coumaric acid. The BP ethanol (50% w/w) extract showed scavenging activity in TEAC, ORAC and FRAP assays with values of 1.45, 2.81, 1.52 mmol Trolox equivalents (TE)/g DW, respectively. Reductions in lipid oxidation were found in samples treated with lyophilized BP extract (0.1% and 0.3% w/w) as manifested by the changes of colour and metmyoglobin concentration. A preliminary study film with BP showed retard degradation of lipid in muscle food. CONCLUSION: The present results indicated that the BP extracts can be used as natural food antioxidants.

Effect of Tara (Caesalpinia spinosa) Pod Powder on the Oxidation and Colour Stability of Pork Meat Batter During Chilled Storage.

The effect of dried pods of Caesalpinia spinosa, known as tara, on pH, cooking loss, lipid oxidation, colour stability and texture of model meat systems stored at 4 °C for 21 days was investigated. Tara pod powder showing a potential antioxidant activity was added at 0.02, 0.04 and 0.08% (by mass) directly to the pork batter and compared with a synthetic antioxidant, butylated hydroxyanisole (BHA) and control (no added antioxidants). The addition of tara pod powder at 0.02% was as effective as BHA (0.02%) in retarding lipid oxidation in pork products during storage. Results showed that redness increased after the addition of tara pod powder. Specifically, 0.02% of tara pod powder was effective in keeping the red colour of meat batter stored under illumination at 4 °C for 48 h. Hardness of pork products was the lowest in samples manufactured with tara pod powder compared with control. Results highlight the potential of using tara pod powder as natural functional ingredient in the development of pork products with enhanced quality and shelf life.

Use of lyophilised and powdered Gentiana lutea root in fresh beef patties stored under different atmospheres.

BACKGROUND: Gentiana lutea root is a medicinal herb that contains many active compounds which contribute to physiological effects, and it has recently attracted much attention as a natural source of antioxidants. The aim of this study was to evaluate the effects on the colour, pH, microbial activities, sensory quality and resistance to lipid oxidation (through the thiobarbituric acid method) during storage of beef patties containing different concentrations of G. lutea. Fresh beef patties were formulated with 0-5 g kg(-1) of G. lutea and 0 or 0.5 g kg(-1) of ascorbic acid and packed in two different atmospheres, Modified Atmosphere 1 (MAP1) and Modified Atmosphere 2 (MAP2), and stored at 4 ± 1 °C for 10 days. MAP1 contained 20:80 (v/v) O2:CO2 and MAP2 contained 80:20 (v/v) O2:CO2. RESULTS: G. lutea extracts possessed antioxidant activity measured by the ferric reducing antioxidant power and the oxygen radical absorbance capacity assays. Beef patties containing 2 g kg(-1) of lyophilised G. lutea were stable towards lipid oxidation in both atmospheres (P < 0.05). Beef patties containing a combination of 2 g kg(-1) G. lutea and 0.5 g kg(-1) ascorbic acid showed significantly reduced changes in colour and in lipid oxidation (P < 0.05). CONCLUSION: The results from this study demonstrate the potential of G. lutea as a food ingredient in the design of healthier meat commodities.

Antioxidant properties of aqueous and ethanolic extracts of tara (Caesalpinia spinosa) pods in vitro and in model food emulsions.

BACKGROUND: The successful replacement of some synthetic food antioxidants by safe natural antioxidants has fostered intensive search for new vegetable sources of antioxidants. In our study the phenol and flavonoid content of extracts of tara pods was determined. The antioxidant activity was also studied by three different analytical assays: the measurement of scavenging capacity against a radical ABTS⁺ , the oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP). RESULTS: All analyzed samples showed a good antioxidant capacity, but the use of a solution of ethanol 75% in a 1 h ultrasonic process allowed achieving the greatest quantity of phenolics (0.464 mg gallic acid equivalent (GAE) g⁻¹ dry weight (DW) ) and the highest antioxidant activity measured by the ABTS⁺ and ORAC methods (10.17 and 4.29 mmol L⁻¹ Trolox equivalents (TE) g⁻¹ DW, respectively). The best method for efficient extraction of flavonoids (3.08 mg catechin equivalent (CE) g⁻¹ DW) was a 24 h maceration in cold water. Two extracts obtained with ethanol 75% and water were added to a model food system (oil-in-water emulsion) and the oxidative stability was studied during storage at 38 °C. Oxidation was monitored by determination of the peroxide value. The addition of 48 µg mL⁻¹ ethanol extract to the emulsion delayed oxidation to the same extent as 17.8 µg mL⁻¹ of Trolox, while water extract was only effective in the early stages of the oxidation process. CONCLUSION: The results of this study indicate that ethanolic tara extracts may be suitable for use in food, cosmetic and nutraceutical applications.

Evaluating the Incorporation of Myrtus communis L. Leaves Infusion in Alginate-Based Films and Spheres to Enhance the Oxidative Stability of Oil-in-Water Emulsions.

Myrtus communis L. is a species of the Myrtaceae family that is found in the Mediterranean region, and it is traditionally recognized for its importance and different uses. The objective of this study was to determine the effect of M. communis L. leaf extract (MCLE), which was incorporated directly into alginate spheres and films, on preserving oil-in-water emulsions from oxidation. For this purpose, the solvent extraction (with ethanol at 40, 60, and 80%) of the antioxidant compounds was optimized (total phenolic compounds (TPCs) and total flavonoid content (TFC)) along with the scavenging activity. The best condition for the extraction corresponded with 60% ethanol (MCLE60), with a TPC of ~66.06 g GAE/L and a TFC of ~18.91 g QE/L, which was selected for use in the following assays. MCLE60 showed a considerable radical scavenging activity (24.85 mmol TE/L in FRAP, 28.75 mmol TE/L in DPPH, 30.61 mmol TE/L in ABTS, and 14.94 mmol TE/L in ORAC), which was probably due to its content in the phenolic compounds arbutin (122.08 mg/L), epicatechin (73.89 mg/L), sinapic acid (51.85 mg/L), and gallic acid (36.72 mg/L). The oil-in-water emulsions with the MCLE60 spheres showed the best oxidative stability (TBARS ~2.64 mg MDA/kg of emulsion, PV ~35.7 meq hydroperoxides/kg of emulsion) in comparison to the control. The film was also able to protect the emulsion from oxidation for more than a week at 30 °C (TBARS ~1.9 mg MDA/kg of emulsion). The alginate films with MCLE60 presented an important release of phenolic compounds in water and acetic food simulants, while in both ethanol simulants, the release of TPC remained more stable over time. Thus, this study highlights the potential uses of MCLE as a natural ingredient for emulsion oxidative preservation and the production of alginate delivery systems (spheres and films).

Antioxidant and Antiradical Activities of Hibiscus sabdariffa L. Extracts Encapsulated in Calcium Alginate Spheres.

The interest in natural sources with high antioxidant powder has recently increased in several sectors. Ionic gelation methods could be used to protect bioactive substances to control the kinetics and release of these ingredients to the food matrix. This study dealt with the evaluation of the antioxidant capacity and scavenging activity of extracts of Hibiscus Sabdariffa L. (HSL) (with 50% ethanol) encapsulated in calcium alginate spheres as a new source for preserving food against oxidative damage. Their antioxidant activity was measured in different o/w emulsions in which HSL spheres reduced the formation of hydroperoxides (~80%) and thiobarbituric-acid-reactive substance products (~20%). The scavenging activity of HSL extracts was measured in different food simulants (water, water acidified with 3% acetic acid, ethanol at 50%, and pure ethanol), and corresponded to 0.20-0.43, 0.31-0.62, and 11.13-23.82 mmol Trolox/mL extract for Trolox equivalent antioxidant capacity (TEAC), 2,2-diphenylpicrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) assays, respectively. In general, the best antiradical activity was observed in the ethanolic and acidified mediums, in which the highest concentration of released polyphenols ranged from 0.068 to 0.079 mg GAE/mL. This work indicates the potential of alginate spheres for encapsulating antioxidant compounds as an innovative strategy for several industrial applications.

Exploring the Potential of Seaweed Derivatives for the Development of Biodegradable Plastics: A Comparative Study.

Biodegradable films made from biopolymer materials have the potential to replace conventional plastics, which can reduce waste disposal problems. This study aims to explore the potential of different seaweed derivate films consisting of 2% (w/w) of kappaphycus alverezi (KA), kappa carrageenan (KC), refined carrageenan (RC) and semi-refined carrageenan (SRC) as bio-based materials with 0.9% (w/w) glycerol (G), and reinforced with different concentrations of cellulose nanofibers (CNFs) derived from palm waste. A characterization of the glycerol-plasticized seaweed derivatives containing 0, 5, 10, and 15% (v/w) cellulose nanofiber is carried out. The CNFs were studied based on their mechanical, physical and thermal properties including mechanical properties, thickness, moisture content, opacity, water solubility, water vapor permeability and thermal stability. The hydrogen bonding was determined using the DFT calculation generated by Gauss view software version 9.6. The KA + G + 10%CNF film exhibited a surface with slight cracks, roughness, and larger lumps and dents, resulting in inferior mechanical properties (18.50 Mpa), making it unsuitable for biofilm production. The KC + G + 10%CNF film exhibited mechanical properties 24.97 Mpa and water vapor permeability of 1.42311 × 10-11 g s-1 m-1 Pa-1. The RC/G/10%CNF film displayed the highest TS (48.23 MPa) and water vapor permeability (1.4168 × 10-11 g s-1 m-1 Pa-1), but it also had higher solubility in water (66%). In contrast, the SRC + G + 10%CNF film demonstrated excellent mechanical properties (45.98 MPa), low water solubility (42.59%), low water vapor permeability (1.3719 × 10-11 g s-1 m-1 Pa-1), and a high decomposition temperature (250.62 °C) compared to KA, KC and RC. These attributes develop films suitable for various applications, including food packaging with enhanced properties and stability.

Brewing By-Products as a Source of Natural Antioxidants for Food Preservation.

Brewer's spent grain (BSG) and brewer's spent hops (BSH) are the major solid by-products of the brewing industry. The present work evaluated their potential as an alternative source of natural antioxidants. The efficacy of different solvents (MilliQ water, 0.75% NaOH, 50% MeOH, 50% MeOH + 0.3% HCl and 50% Acetone) for extracting polyphenols of these by-products was firstly evaluated, with NaOH showing the best results. The extraction conditions were optimized using the response surface methodology, and were determined to be 1.45% NaOH and 80 °C. BSG extracts showed the highest total polyphenol content (24.84-38.83 µmol GAE/g), whereas the BSH showed the lowest value (24.84 ± 1.55 µmol GAE/g). In general, BSG extracts presented significantly higher antioxidant capacity (ABTS, ORAC). Ferulic acid was the main polyphenol in all BSG extracts (156.55-290.88 mg/100 g), whereas in BSH, this compound was not detected. The addition of 10% BSG extract in o/w emulsions (stored 14 days) showed a reduction in the formation of primary oxidation products of 97%. In the emulsions covered with polylactic acid active films (1% BSG), this reduction corresponded to 35%. Hence, this study demonstrates the potential of these by-products as natural antioxidant sources for protecting food systems against oxidation.

Effects of Water Deficit Irrigation on Phenolic Composition and Antioxidant Activity of Monastrell Grapes under Semiarid Conditions.

The high phenolic compound content of grapes makes them an important source of natural antioxidants, among other beneficial health properties. Vineyard irrigation might affect berry composition and quality. Regulated deficit irrigation (RDI) is a widely used strategy to reduce the possible negative impact of irrigation on grapes, improving grape composition and resulting in water savings. Monastrell grapevines (Vitis vinifera L.) grown in eastern Spain were subjected to two water regime strategies: rainfed (non-irrigation) and RDI. The content of anthocyanins, flavonols, flavanols, hydroxybenzoic and hydroxycinnamic acids, and stilbenes was determined by HPLC and was related with total phenolic content and three antioxidant activity methods (ABTS, DPPH, and ORAC). The study aimed to evaluate and compare the phenolic composition and antioxidant potential of Monastrell grapes. The rainfed regime concentrated grapes in terms of phenolic compounds. Thus, total content of anthocyanins, flavonols, flavanols, hydroxybenzoic acids, and total phenols were higher in the rainfed grapes than in the RDI ones. Besides, the rainfed grapes doubled their antioxidant potential with respect to the RDI grapes with the ORAC method. Total phenolic content and antioxidant activity by ORAC assay positively correlated with most of the total phenolic compounds analyzed. This study demonstrates how field practices can modulate final grape composition in relation to their antioxidant activity.

Characterization and Application of Gelatin Films with Pecan Walnut and Shell Extract (Carya illinoiensis).

Phenolic compounds that come from natural products are a good option for minimizing lipid oxidation. It should be noted that these are not only introduced directly into the food, but also incorporated into edible biofilms. In contact with food, they extend its useful life by avoiding contact with other surface and preventing deterioration air, one of the main objectives. In particular, gelatin is a biopolymer that has a great potential due to its abundance, low cost and good film-forming capacity. The aim of this study has been to design and analyse gelatin films that incorporate bioactive compounds that come from the walnut and a by-product, the walnut shell. The results showed that mechanical and water vapor barrier properties of the developed films varied depending on the concentration of the walnut, shell and synthetic antioxidant. With increasing walnut concentration (15%) the permeability to water vapor (0.414 g·mm/m2·day·Pascal, g·mm/m2·day·Pa) was significantly lower than the control (5.0368 g·mm/m2·day·Pa). Furthermore, in the new films the elongation at the break and Young's modulus decrease by six times with respect to the control. Films with pure gelatin cannot act as an antioxidant shield to prevent food oxidation, but adding pecan walnut (15% concentration) presents 30% inhibition of the DPPH stable radical. Furthermore, in the DSC, the addition of walnut (15 and 9% concentrations), showed the formation of big crystals; which could improve the thermal stability of gelatin films. The use of new gelatin films has shown good protection against the oxidation of beef patties, increasing the useful lifetime up to nine days, compared to the control (3-4 days), which opens up a big field to the commercialization of meat products with lower quantities of synthetic products.

Chitosan-Based Drug Delivery System: Applications in Fish Biotechnology.

Chitosan is increasingly used for safe nucleic acid delivery in gene therapy studies, due to well-known properties such as bioadhesion, low toxicity, biodegradability and biocompatibility. Furthermore, chitosan derivatization can be easily performed to improve the solubility and stability of chitosan-nucleic acid polyplexes, and enhance efficient target cell drug delivery, cell uptake, intracellular endosomal escape, unpacking and nuclear import of expression plasmids. As in other fields, chitosan is a promising drug delivery vector with great potential for the fish farming industry. This review highlights state-of-the-art assays using chitosan-based methodologies for delivering nucleic acids into cells, and focuses attention on recent advances in chitosan-mediated gene delivery for fish biotechnology applications. The efficiency of chitosan for gene therapy studies in fish biotechnology is discussed in fields such as fish vaccination against bacterial and viral infection, control of gonadal development and gene overexpression and silencing for overcoming metabolic limitations, such as dependence on protein-rich diets and the low glucose tolerance of farmed fish. Finally, challenges and perspectives on the future developments of chitosan-based gene delivery in fish are also discussed.