Identification of phenolic compounds in soursop (Annona muricata) pulp by high-performance liquid chromatography with diode array and electrospray ionization mass spectrometric detection

Soursop (Annona muricata L., Annonaceae) is a neotropical fruit species producing large fruits that can be consumed fresh and mainly processed. While the leaves, roots and stems of this species have been the subject of reiterated phytochemical studies, their fruits have received less attention. Phenolic compounds were extracted from the pulp of ripe soursop fruits and separated into two fractions by solid phase extraction. The first was eluted with water and HCl (0.01%), while the second was obtained with ethyl acetate. Their characterization was conducted with high-performance liquid chromatography with diode array and electrospray ionization mass spectrometric detection. The analytical system allowed the separation and tentative identification of 16 phenolic compounds, mainly based on MS fragmentation patterns. Prevalent compounds were a cinnamic acid derivative and p-coumaric acid, together with several other minor compounds that may have health benefits due to antioxidant characteristics. To the best of our knowledge, this is the first study on the phenolic composition of soursop fruit pulp based on a mass spectrometric method.German Academic Exchange Service/[]/DAAD/AlemaniaUCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de AlimentosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS

Genetic diversity analysis based on molecular marker and quantitative traits of the response of different tomato (Lycopersicon esculentum Mill.) cultivars to drought stress

The drought tolerance of tomato (Lycopersicon esculentum Mill.) is a trait needing urgent improvement due to recent climate changes and limited water availability. We therefore conducted a greenhouse screening experiment to identify tomato cultivars with improved drought tolerance. Several sensitivity and tolerance indices were computed based on morphological markers. With the aim of establishing a correlation to these markers, a total of 16 inter-simple sequence repeat (ISSR) primers were used, the genetic diversity among cultivars was elucidated and clustering the cultivars into groups based on their molecular profiles was performed. The obtained results indicated that selection indices, such as geometric mean productivity (GMP), mean productivity (MP), tolerance index (TOL),and stress tolerance index (STI), represented suitable indices for screening the drought tolerance of tomato cultivars. An interesting correlation of the ISSR analyses to these morphological findings was established according to 83 detectable fragments derived from 10 primers. The highest value of the effective multiplex ratio (EMR) and marker index (MI) was detected for primer INC7 followed by INC1. Based on Jaccard's similarity coefficients, the genetic distance of the genotypes varied from 0.702 to 0.942 with a mean value of 0.882. The results showed a clear-cut separation of the 15 tomato cultivars due to their genetic variability, making them a valuable genetic source for their incorporation into potential breeding programs. Molecular data were in good agreement with the results as regards selection indices, and both of them will be useful tools for improvement of the tomato germplasm

Ultrastructural deposition forms and bioaccessibility of carotenoids and carotenoid esters from goji berries (Lycium barbarum L.)

Goji berries (Lycium barbarum L.) have been known to contain strikingly high levels of zeaxanthin, while the physical deposition form and bioaccessibility of the latter was yet unknown. In the present study, we associated ripening-induced modifications in the profile of carotenoids with fundamental changes of the deposition state of carotenoids in goji berries. Unripe fruit contained common chloroplast-specific carotenoids being protein-bound within chloroplastidal thylakoids. The subsequent ripening-induced transformation of chloroplasts to tubular chromoplasts was accompanied by an accumulation of up to 36 mg/100 g FW zeaxanthin dipalmitate and further minor xanthophyll esters, prevailing in a presumably liquid-crystalline state within the nano-scaled chromoplast tubules. The in vitro digestion unraveled the enhanced liberation and bioaccessibility of zeaxanthin from these tubular aggregates in goji berries as compared to protein-complexed lutein from spinach. Goji berries therefore might represent a more potent source of macular pigments than green leafy vegetables like spinach

Deposition Form and Bioaccessibility of Keto-carotenoids from Mamey Sapote (Pouteria sapota), Red Bell Pepper (Capsicum annuum), and Sockeye Salmon (Oncorhynchus nerka) Filet

The ultrastructure and carotenoid-bearing structures of mamey sapote (Pouteria sapota) chromoplasts were elucidated using light and transmission electron microscopy and compared to carotenoid deposition forms in red bell pepper (Capsicum annuum) and sockeye salmon (Oncorhynchus nerka). Globular−tubular chromoplasts of sapote contained numerous lipid globules and tubules embodying unique provitamin A keto-carotenoids in a lipid-dissolved and presumably liquid-crystalline form, respectively. Bioaccessibility of sapotexanthin and cryptocapsin was compared to that of structurally related ketocarotenoids from red bell pepper and salmon. Capsanthin from bell pepper was the most bioaccessible pigment, followed by sapotexanthin and cryptocapsin esters from mamey sapote. In contrast, astaxanthin from salmon was the least bioaccessible ketocarotenoid. Thermal treatment and fat addition consistently enhanced bioaccessibility, except for astaxanthin from naturally lipidrich salmon, which remained unaffected. Although the provitamin A keto-carotenoids from sapote were highly bioaccessible, their qualitative and quantitative in vivo bioavailability and their conversion to vitamin A remains to be confirmed.Centro Agronómico Tropical de Investigación y Enseñanza, Universidad de Costa Rica/[]/CATIE/Costa RicaAlexander von Humboldt Foundation/[]//GermanyUniversity of Costa Rica/ [Project VI-735-B2-A16]/UCR/Costa Rica.Research Center on Microscopic Structures and the Research Vice-Rectory of the University of Costa Rica/[Project VI-810-B3-183]/CIEMIC/Costa RicaGerman Academic Exchange Service/[]/DAAD/GermanyUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Estructuras Microscópicas (CIEMIC)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimento

Effect of processing on biofunctionality of selected tropical fruit juices

This review compiles the current state of knowledge on the effects of processing using thermal and nonthermal technologies and fermentation on selected compounds in potentially health-promoting tropical fruit juices, specifically those of pineapple, pitaya, guava, and papaya. The most relevant functional compounds in pineapple fruit are phenolic compounds, carotenoids, and vitamin C. Pitaya fruit functional properties are mainly defined by the presence of betalains, heat-labile molecules with high antioxidant potential. The guava fruit is very-well-known because of its high ascorbic acid contents and, depending on the genetic background, also lycopene and anthocyanins. Finally, the relevance of the papaya fruit relies mostly on high carotenoid contents and their role as precursors of vitamin A and as antioxidants. For every case, the pertinent functional constituents are summarized followed by a description of the effect of conventional and emerging processing strategies on their retention. Fermentation is also mentioned as an option to improve biofunctionality in certain cases.Universidad de Costa Rica/[735-C0-750]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de AlimentosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Instituto de Investigaciones Agrícolas (IIA

Spectral detection of stress-related pigments in salt-lake succulent halophytic shrubs

The spectral detection of vegetation pigment concentrations has a high potential value, but it is still underdeveloped, especially for pigments other than chlorophylls. In this study, the seasonal pigment dynamics of two Tecticornia species (samphires; halophytic shrubs) from north-western Australia were correlated with spectral indices that best document the pigment changes over time. Pigment dynamics were assessed by analysing betacyanin, chlorophyll and carotenoid concentrations at plant level and by measuring reflectance at contrasting seasonal dates. Plant reflectance was used to define a new reflectance index that was most sensitive to the seasonal shifts in Tecticornia pigment concentrations. The two Tecticornia species turned from green to red-pinkish for the period March–August 2012 when betacyanins increased almost nine times in both species. Chlorophyll levels showed the opposite pattern to that of betacyanins, whereas carotenoid levels were relatively stable. Normalised difference indices correlated well with betacyanin (r = 0.805, using bands at 600 and 620 nm) and chlorophyll (r = 0.809, using bands at 737 and 726 nm). Using knowledge of chlorophyll concentrations slightly improved the ability of the spectral index to predict betacyanin concentration (r = 0.822 at bands 606 and 620 nm, in the case of chemically determined chlorophyll, r = 0.809 when using remotely sensed chlorophyll). Our results suggest that this new spectral index can reliably detect changes in betacyanin concentrations in vegetation, with potential applications in ecological studies and environmental impact monitoring.Fil: Marchesini, Victoria Angela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina. University of Western Australia; AustraliaFil: Guerschman, Juan P.. Csiro Land and Water; AustraliaFil: Schweiggert, Ralf M.. Universidad de Hohenheim; AlemaniaFil: Colmer, Timothy D.. University of Western Australia; AustraliaFil: Veneklaas, Erik J.. University of Western Australia; Australi

Studies into the Stability of 3‑<i>O</i>-Glycosylated and 3,5-<i>O</i>-Diglycosylated Anthocyanins in Differently Purified Liquid and Dried Maqui (Aristotelia chilensis (Mol.) Stuntz) Preparations during Storage and Thermal Treatment

Anthocyanin stabilities in diluted and differently purified maqui preparations were assessed during storage and thermal treatment at different pH values. By sequentially depleting the matrix, the influence of polar low-molecular-weight matrix constituents and non-anthocyanin phenolics was shown to be negligible. In contrast, pH substantially affected thermal stabilities of differently glycosylated cyanidin and delphinidin derivatives. At pH 3.6, half-lives of 3-<i>O</i>-glycosides were substantially shorter than those of respective 3,5-<i>O</i>-diglycosides. However, at pH 2.2, an inverse stability behavior was observed. Findings were corroborated using isolated pigments. Upon heating, cyanidin derivatives were more stable than their respective delphinidins, but their stability was similar during storage. Anthocyanins in liquid samples were more stable when stored at 4 °C as compared to 20 °C, whereas those in dried powders revealed maximum stability throughout storage. The study contains a detailed discussion and mechanistic hypothesis for the above-mentioned findings, providing insights relevant for food applications of maqui anthocyanins

Formas de deposición de carotenoides en alimentos vegetales y sus posibles implicaciones en su bioaccesibilidad y biodisponibilidad

En las plantas, los carotenoides son generalmente biosintetizados y depositados en diferentes tipos de plastidios. En tejidos vegetales verdes, los carotenoides se encuentran dentro de cloroplastos, los cuales tienen morfología y composición similar. En tejidos vegetales no verdes, estos pigmentos se encuentran en cromoplastos, los cuales pueden tener cierta diversidad estructural (Cazzonelli y Pogson, 2010). Se han descrito cuatro formas de deposición de carotenoides en cromoplastos: aquellos que están disueltos en lípidos, en forma líquido-cristalina, asociados a membranas y en forma sólido-cristalina. Se postula que el tipo de plastidio en el que se encuentran puede tener una importante influencia en la biodisponibilidad de los carotenoides (Schweiggert et al., 2012). Debido a ello, la caracterización ultra-estructural de estos orgánulos es interesante para estimar el potencial de un material vegetal en particular como fuente de carotenoides biodisponibles.UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimento