Different Citrus rootstocks present high dissimilarities in their antioxidant activity and vitamins content according to the ripening stage

“Lane Late” sweet orange grafted on six different citrus rootstocks and grown in the Guadalquivir valley (Seville, Spain) were picked at different ripening stages in two consecutive seasons to characterize their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and quantify their main antioxidant compounds (vitamin E and vitamin C). Linear discriminant analysis and 2-way ANOVA were applied to compare the effects induced by citrus rootstock and ripening stage. The results showed that differences in antioxidant activity and related compounds are mainly dependent on the citrus rootstock, despite ripening stage had also some particular effects. Changes observed in 2012 showed less marked differences among the citrus rootstock. Nevertheless, Cleopatra rootstock showed the highest antioxidant activity in both years, indicating that an increase in its cultivation might be a good solution to sweet orange farmers. Concerning the ripening stage, samples collected in January presented higher vitamin contents, while those collected in April showed higher antioxidant activity. This result allows deciding the harvesting period according to the desired effect.Foundation for Science and Technology (FCT, Portugal) for financial support to the research center CIMO (strategic project PEst-OE/AGR/UI0690/2011), J.C.M. Barreira grant (SFRH/BPD/72802/2010) and L. Barros researcher contract under “Programa Compromisso com Ciência - 2008”. And Vanessa Cardeñosa is grateful to IFAPA for the fellowship obtained for the development of her PhD thesis

Variety and Harvesting Season Effects on Antioxidant Activity and Vitamins Content of Citrus sinensis Macfad.

Five sweet orange (Citrus sinensis Osbeck) varieties cultivated in Huelva (Spain) and picked at two seasons during two consecutive years, were characterized for their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and vitamin content (vitamin E and vitamin C). The effects induced by sweet orange variety and stage of maturity were comprehensively compared by applying 2-way ANOVA and linear discriminant analysis. The results indicated higher differences in antioxidant activity and vitamin contents in response to the effect of the harvesting season, when compared to the effect of sweet orange variety. Nevertheless, the results observed in 2012 showed less marked differences among the assayed sweet orange varieties. Either way, it might be concluded that oranges sampled in January show the highest antioxidant activity and vitamin contents. Furthermore, concerning the properties evaluated in this work, all sweet orange varieties represent good alternatives, except for Rhode Summer, which would not be the preferable choice as a target to enhance sweet orange overall characteristics

Efecto de los factores precosecha sobre la calidad nutricional y los compuestos bioactivos en fresas y naranjas

Existe una tendencia general hacia un mayor consumo y variedad de frutas y hortalizas. Los consumidores demandan calidad en términos de apariencia, frescura, presentación así como de valor nutricional. Pero, hay que tener en cuenta que tanto el genotipo, como el estado de madurez, el manejo en la producción y los factores medioambientales pueden influir en todos estos aspectos relacionados con la calidad de las frutas y hortalizas. Esta tesis tiene seis capítulos con diferentes estrategias para mejorar la calidad general de las frutas estudiadas, que en este caso se trata de fresas y naranjas. El capítulo uno trata de ofrecer una introducción que contextualice el tema a tratar en este documento y los objetivos que se persiguen, se muestran en el capítulo dos. El tercer capítulo se centra en la evaluación de los efectos de la salinidad y el aporte de nitrógeno en la calidad y en los compuestos relacionados con la salud (compuestos antioxidantes) en fresa (Fragaria × ananassa cv. Primoris). Este estudio se llevó a cabo porque diferentes aportes de nitrógeno y/o el desarrollo en condiciones de agua adversas (como estrés hídrico/ baja calidad del agua de riego y/o alta salinidad/ conductividad eléctrica), como las que prevalecen en Almería (España), pueden afectar a la calidad en general de frutas y hortalizas. En resumen, los resultados obtenidos en este trabajo fueron que las fresas cosechadas bajo tratamientos de salinidad registraron los valores más altos en el contenido de sólidos solubles (SSC) y por lo tanto, puede verse reflejado en una mejora de la percepción sensorial en fresa. Además, la salinidad afectó al valor nutricional de la fresa, obteniendo una mayor capacidad antioxidante (DPPH) para las fresas sometidas a este tratamiento. Durante el primer y segundo muestreo, las fresas cultivadas bajo las condiciones de menor aporte de N y tratamiento no salino mostraron los valores más altos de la firmeza con respecto a las frutas cultivadas bajo otros tratamientos. En cuanto a los compuestos relacionados con la salud, se encontraron pocas diferencias en los parámetros estudiados dentro de cada tiempo de muestreo pero, para la primera fecha de muestreo en el caso de las fresas cultivadas bajo tratamiento con mayor solución salina, se obtuvieron los valores más altos de concentración de polifenoles totales (PPT) y de actividad antioxidante (DPPH). En conclusión: El uso de agua de baja...There is a general tendency towards greater consumption and variety of fruits and vegetables. The consumer demands are related to quality in terms of appearance, freshness, presentation as well as nutritional value. Fruit or vegetable genotype and maturity; production inputs and the growing environment may influence all this aspects connected to fruit and vegetable quality. This thesis holds six chapters with different strategies to improve the overall quality of orange and strawberry fruits. Chapter one contextualizes the topic stated in this document and the objectives pursued are shown in chapter two. Chapter three is focused on the evaluation of the effects of salinity and nitrogen supply on the quality and health-related compounds of strawberry fruits (Fragaria × ananassa cv. Primoris). Different nitrogen inputs and/or development under adverse water conditions (water stress/low quality and/or high salinity/electrical conductivity), such as those prevailing in Almeria (Mediterranean coast, south-east Spain), may affect overall fruit and vegetable quality. In summary, the results obtained were that strawberries harvested under salinity treatments recorded the highest values for soluble solids content (SSC) and therefore, sensory perception of strawberry fruits was enhanced. Additionally, salinity impacted on fruit nutritional value, with higher antioxidant capacity (DPPH). During first and second samplings, strawberries grown under N reduction and non-saline conditions showed higher values for firmness compared to fruits developed under other treatments. Regarding healthrelated compounds, few differences were found for the studied parameters within each sampling time but, for the first sampling for strawberries grown under saline treatment, we obtained the highest values for total polyphenols (PPT) concentration and antioxidant activity (DPPH). In conclusion: The use of low-quality waters, such as those found in Almeria (high salinity) and low nitrogen inputs (diminishing environmental impact) for strawberry cultivation does not exert a negative impact on the overall quality of fruits. In fact, positive differences could be found in SSC, firmness and health-related compounds when compared the different treatments with the control one..

Variety and Harvesting Season Effects on Antioxidant Activity and Vitamins Content of Citrus sinensis Macfad.

Five sweet orange (Citrus sinensis Osbeck) varieties cultivated in Huelva (Spain) and picked at two seasons during two consecutive years, were characterized for their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and vitamin content (vitamin E and vitamin C). The effects induced by sweet orange variety and stage of maturity were comprehensively compared by applying 2-way ANOVA and linear discriminant analysis. The results indicated higher differences in antioxidant activity and vitamin contents in response to the effect of the harvesting season, when compared to the effect of sweet orange variety. Nevertheless, the results observed in 2012 showed less marked differences among the assayed sweet orange varieties. Either way, it might be concluded that oranges sampled in January show the highest antioxidant activity and vitamin contents. Furthermore, concerning the properties evaluated in this work, all sweet orange varieties represent good alternatives, except for Rhode Summer, which would not be the preferable choice as a target to enhance sweet orange overall characteristics

Widespread diversity deficits of coral reef sharks and rays

A global survey of coral reefs reveals that overfishing is driving resident shark species toward extinction, causing diversity deficits in reef elasmobranch (shark and ray) assemblages. Our species-level analysis revealed global declines of 60 to 73% for five common resident reef shark species and that individual shark species were not detected at 34 to 47% of surveyed reefs. As reefs become more shark-depleted, rays begin to dominate assemblages. Shark-dominated assemblages persist in wealthy nations with strong governance and in highly protected areas, whereas poverty, weak governance, and a lack of shark management are associated with depauperate assemblages mainly composed of rays. Without action to address these diversity deficits, loss of ecological function and ecosystem services will increasingly affect human communities