Cristóbal Espinosa

Chemical and functional properties of the different by-products of artichoke (Cynara scolymus L.) from industrial canning processing

In this study, the basic chemical composition and functional properties of six by-product fractions collected from different steps of artichoke industrial processing were evaluated. Fractions differed in thermal treatment, the bract position in the artichoke head and the cutting size. Contents of moisture, ash, protein, fat, dietary fibre, inulin, total phenolics, total flavonoids, caffeoyl derivatives and flavones were analysed. Antioxidant activity values were also determined. All assessed artichoke by-product fractions contained high-dietary fibre (53.6-67.0%) and low fat (2.5-3.7%). Artichoke by-product fractions contained high levels of inulin, especially in the boiled inner bracts (30%). Total phenolic and flavonoid contents and antioxidant activity (153-729 μmol gallic acid equivalents, 6.9-19.2 μmol quercetin equivalents and 85-234 μmol ascorbic acid equivalents per gram of dry matter, respectively) varied widely with the bract positions in the artichoke head and the thermal treatments. The more interesting fractions for use as functional ingredients were those situated closer to the artichoke heart and thermally treated.

Protective effect of white tea extract against acute oxidative injury caused by adriamycin in different tissues.

Adriamycin (ADR) is an anticancer agent that increases oxidative stress in cells. We evaluated the protective effect of the long term consumption of white tea at two different doses against this drug. For this purpose rats were given distilled water (controls), 0.15 mg (Dose 1) or 0.45 mg (Dose 2) of solid tea extract/kg body weight for 12 months. All the animals received an injection of ADR, except half of the control group, which were given an injection of saline solution. This gave four experimental groups: Control (C), C+ADR, Dose 1+ADR, and Dose 2+ADR. The antioxidant activity (in liver, heart and brain microsomes) was analysed. White tea consumption for 12 months, at a non-pharmacological dose, reversed the oxidative damage caused by ADR, on both protein and lipid levels in all three organs. The heart recovered its antioxidant activity only at the highest dose of tea.

Effects of dietary polyvinylchloride microparticles on general health, immune status and expression of several genes related to stress in gilthead seabream (Sparus aurata L.)

Abstract It is a long‐recognized fact that marine plastic debris contaminates the oceans and seas of the entire world. Even though their effects on the aquatic biota are not well documented or understood. The effects of dietary polyvinylchloride microparticles (PVC‐MPs) on the general health, immune status and some stress markers were studied using gilthead seabream (Sparus aurata) as a model of marine fish. Thirty specimens were randomly placed in three running sea water aquaria and fish in each aquarium received an experimental diet containing 0 (control), 100 or 500 mg kg−1 of PVC‐MPs for 30 days. Metabolic parameters in serum indicated that the dietary intake of PVC‐MPs negatively affected several vital organs. Humoral immune parameters were determined in serum and skin mucus. Cellular immune parameters were determined in head‐kidney leucocytes. Concomitantly, the expression of different genes related to stress was studied in head‐kidney and liver. Regarding head‐kidney gene expression, prdx5 was significantly decreased by PVC‐MPs intake for 15 and 30 days, respect to the values found in control fish. On the other hand, the expression of prdx1 and prdx3 were significantly increased by the PVC‐MPs intake during 15 and 30 days, compared with the values found in control fish. Furthermore, the expression of hsp90 and ucp1 genes decreased and increased, respectively, in the liver of fish fed 500 mg kg−1 of PVC‐MPs for 30 days. Although ingestion of PVC‐MPs provoked few significant effects (mostly increases) in the main immune activities of gilthead seabream compared with the values found in control fish, PVC‐MPs are recognized by the fish as stressors. Continued exposure of fish to high concentrations of PVC‐MPs could have a negative impact on fish physiology due to the chronic stress produced. HighlightsFish were fed with 0, 100 or 500 mg kg−1 of PVC microplastics for 30 days.Aspartate aminotransferase and creatine kinase activities as well as albumin and glucose levels were increased.Ingestion of PVC‐MPs provokes few significant effects on the main immune activities.PVC microplastics diet induced stress in fish.

Microplastics in Aquatic Environments and Their Toxicological Implications for Fish

The intensive use of plastics and derivatives during the last century has increased the contamination of animal habitats. The breakdown of these primary plastics in the environment results in microplastics (MP), small fragments of plastic typically <1–5 mm in size. Apart from the potential negative effects of the MPs per se, it is generally assumed that microplastics may increase the exposure of marine aquatic organisms to chemicals associated with the plastics. In addition, to enhance the performance of plastics, additives are added during manufacture. Furthermore, they are active in absorbing other contaminants and be used as vectors of highly and well‐documented persistent contaminants. Finally, these small MPs are easily ingested by animals and affect their physiology and behaviour. Thus, aquatic living organisms are continuously exposed to these MPs, and associated contaminants, and could suffer from its contamination but also introduce them into the food chain.

Long-term intake of white tea prevents oxidative damage caused by adriamycin in kidney of rats.

BACKGROUND White tea infusion (Camelia sinensis) has antioxidants properties. The infusion contains polyphenols that have been proposed to induce antioxidant response element (ARE) response via nuclear factor E2-related factor 2 (NRF2). Adriamycin (ADR) has antitumour properties and oxidative effects. Oxidative stress is related to a variety of kidney diseases. Prevention of the oxidative stress through long-term intake of white tea and the study of the molecular mechanisms involved in protection could be of great interest. Rats were given distilled water, 0.015 or 0.045 g of solid white tea extract kg(-1) body weight for 12 months. Animals received an injection of ADR. In kidney, oxidative stress parameters were measured, the expressions of nuclear factor E2-related factor 2 gene (Nrf2), and detoxifying and antioxidants genes were analysed, and the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) were measured. RESULTS ADR administration increased oxidative parameters and decreased the antioxidant activity; significantly increased the expression of analysed genes and the activity of CAT and SOD and decreased GR activity. The highest white tea dose protected redox status and inhibited ARE response. CONCLUSION Long-term intake of white tea protected kidney against the oxidative stress. ADR activated the ARE response but in animals treated with the highest dose of white tea, this response was inhibited, probably for antioxidant protection.

Dietary dehydrated lemon peel improves the immune but not the antioxidant status of gilthead seabream (Sparus aurata L.)

ABSTRACT Lemon (Citrus limon) is the third most important species of citrus in the world, while Spain is the major producer in Europe. Numerous beneficial effects of lemon are known, which explains their use in traditional medicine. The paper describes the effect of dietary dehydrated lemon peel (a sub‐product of the lemon industry) on the growth, immune and antioxidant status of gilthead seabream (Sparus aurata L.) over a period of 30 days. Fish fed diets enriched with dehydrated lemon peel (1.5% and 3%) for 15 days showed improved growth and both humoral (seric immunoglobulin M) and cellular (peroxidase activity and phagocytic ability of head kidney leucocytes) immunity, as well as the expression of some immune‐related genes (nkefa, il1&bgr;, igth and csfr1). However, decreases growth promotion was observed after thirty days of trial. Neither the anti‐oxidant enzymes activity nor the expression of several anti‐oxidants and anti‐stress genes in liver was improved by the diet. The possible inclusion of dehydrated lemon peel in fish diets for its immunostimulant effects is discussed. HIGHLIGHTSDietary dehydrated lemon peel (DLP) for 15 days improved gilthead seabream immunity.Supplemented DLP diets improved leucocyte, serum and skin mucus immune activities.Immune‐related gene expression was stimulated by the supplemented diets.More concentrated diet (3% DLP) decreased weight and growth promotion at 30 days.Dehydrated lemon peel could be considered as a good dietary supplement.

Molecular oxidative stress markers in olive ridley turtles (Lepidochelys olivacea) and their relation to metal concentrations in wild populations

Due to their longevity and extensive migration areas, marine turtles are able to accumulate diverse contaminants over many years and as a consequence they represent an interesting bioindicator species for marine ecosystem pollution. Metals provoke toxicological effects in many aquatic animal species, but marine turtles have been under-investigated in this area. Thus, we have determined the presence of certain inorganic elements (As, Cd, Cu, Ni, Pb, Se and Zn) in olive ridley turtles (Lepidochelys olivacea) and related them to metallothionein (MT), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) transcription and/or enzymatic activities. Gene expression of sod, cat and gr was found to be higher in blood than liver or kidney but most of the significant relationships were found in liver, not only for gene expression but also for enzyme activities. This must be related to the role the liver has as the first filter organ. Several positive relationships of sod, cat and gr gene expression in the different tissues were found in this population, as well as very high Cd concentrations. This could mean that these turtles are adapting to the metals-production of ROS and damage through a high transcription of these antioxidants. Multiple positive relationships with GR seem to be part of its compensatory effect due to the decrease of SOD production against the high and chronic exposure to certain xenobiotics. CAT, on the other hand, seems not to be used much, and glutathione detoxification of H2O2 may be more important in this species. Finally, despite the very high Cd concentrations found in this population, no significant relationship was found in any tissue with metallothionein gene expression. These results, along with very high Cd concentrations and a negative relationship with Cu, lead us to consider some kind of disruption in mt gene expression in these turtles.

First synthesis of pyrene-functionalized silatranes for mechanistic insights into their potential anti-parasitic and anti-oxidation activities

The known silatranes have attached substituents such as hydrogen, organyl, organoxy, aminoalkyl, thioorganyl, acyloxy, halogen, pseudohalogen, and other groups; however, their functionalization with any polycyclic aromatic hydrocarbon substituent is not recognized; this creates a niche in silatrane chemistry. The current study involves the first synthesis of pyrene-functionalized silatranes starting from 1-pyrenecarboxaldehyde and aminopropylsilane, fulfilling the niche. These newly synthesized silatranes were structurally characterized by IR spectroscopy, multinuclear NMR (1H and 13C) spectroscopy, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), and thermogravimetric analysis, and the structure of one of the silatranes was further confirmed by single crystal XRD analysis. The protozoans Giardia lamblia and Trichomonas vaginalis are responsible for a significant number of intestinal infections, and antioxidants are needed to prevent the formation of reactive species in the body. In the present study, anti-oxidant, anti-giardiasis, and anti-trichomoniasis potential of the synthesized compounds were assessed. Both compounds displayed significant activity against G. lamblia and T. vaginalis and showed potential anti-oxidant activity. The results indicate that one of the compounds is even more active against G. lamblia than metronidazole, a standard drug. Moreover, a theoretically and electrochemically supported mechanism for the anti-oxidant activity of the compounds has been reported in this study.

EFFECT OF LONG TERM INTAKE OF WHITE TEA ON ACUTE OXIDATIVE STRESS IN RATS.

INTRODUCTION the well known antioxidant properties of white tea include the prevention of cancer, neurodegenerative diseases and oxidative stress. Adriamycin can generate an amount of oxidative stress in vivo. OBJECTIVE evaluate long term intake of white tea on plasma antioxidant capacity and on the fatty acid profile of liver and heart microsomes in animals subjected to acute oxidative stress. METHODS rats were given distilled water (controls), 15 mg/d (dose 1) or 45 mg/d (dose 2) of solid white tea extract/per kilogram of body weight for 12 months. After this time, all the animals received an injection of adriamycin (ADR) (10 mg/kg body weight), except half of the control group, which were given an injection of saline solution. Samples of plasma and liver and heart were taken. The antioxidant activity, the carbonyl groups and hydroperoxide concentration were analyzed in plasma, and the fatty acid profiles of liver and heart microsomes were obtained. RESULTS & DISCUSSION only the hydroperoxides showed significant changes, while slight tendencies were observed in antioxidant activity and the carbonyl groups. Although the long term intake of white tea and the administration of adriamycin did not change the fatty acid profile, slight tendencies existed for the SFAs, MUFAs and PUFAs.