García Carmona, Francisco

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García Carmona, Francisco

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Formation of carboxylated and decarboxylated betalains in ripening grains of Chenopodium quinoa by a dual dioxygenase
(Oxford University Press, Society for Experimental Biology, 2022-04-07) Henarejos Escudero, Paula; Martínez-Rodríguez, Pedro; Gomez-Pando, Luz Rayda; Gandía Herrero, Fernando; García Carmona, Francisco; Bioquímica y Biología Molecular "A"
Chenopodium quinoa (quinoa) is a pseudo-cereal that forms part of the cultural heritage of Andean countries, and its grains have high nutritional value and potential health benefits. Betalains are nitrogenous water-soluble pigments and bioactive molecules that contribute to these health-promoting properties. Betalains are restricted to plants of the order Caryophyllales, to which quinoa belongs. A new family of betalains has been discovered in the form of unconventional decarboxylated pigments. Here, we show that these pigments accumulate in ripening quinoa grains of fluorescent nature, and are putatively based on a dopamine-cleaving activity. This study describes for the first time the purification and molecular and functional characterization of a 4,5-dopamine extradiol dioxygenase enzyme from plants. It is a monomeric protein with a molecular mass of 34.5 kDa characterized by chromatography, electrophoresis, and time-offlight mass spectrometry. We demonstrate that this key enzyme has a dual function in a square-shaped biosynthetic pathway towards the formation of both carboxylated and decarboxylated pigments. Enzyme kinetic properties are characterized for the production of 6-decarboxy-betalamic acid and 3,4-dihydroxy-l-phenylalanine-derived betalamic acid, the two structural units of plant pigment in nature. The profile of multiple betalains present in quinoa grains has been reproduced in one-pot bioreactors containing the novel enzyme and two competing substrates
Open Access
Purification and characterization of Terfezia claveryi TcCAT-1, a desert truffle catalase upregulated in mycorrhizal symbiosis
(Public Library of Science, 2019-07-10) Marqués Gálvez, José Eduardo; Morte Gómez, María Asunción; Navarro Ródenas, Alfonso; Pérez Gilabert, Manuela; García Carmona, Francisco; Biología Vegetal; Facultades de la UMU::Facultad de Biología
Terfezia claveryi Chatin is a mycorrhizal fungus that forms ectendomycorrhizal associations with plants of Helianthemum genus. Its appreciated edibility and drought resistance make this fungus a potential alternative crop in arid and semiarid areas of the Mediterranean region. In order to increase the knowledge about the biology of this fungus in terms of mycorrhiza formation and response to drought stress, a catalase from T. claveryi (TcCAT-1) has been purified to apparent homogeneity and biochemically characterized; in addition, the expression pattern of this enzyme during different stages of T. claveryi biological cycle and under drought stress conditions are reported. The results obtained, together with the phylogenetic analysis and homology modeling, indicate that TcCAT-1 is a homotetramer large subunit size monofunctional-heme catalase belonging to Clade 2. The highest expression of this enzyme occurs in mature mycorrhiza, revealing a possible role in mycorrhiza colonization, but it is not upregulated under drought stress. However, the H2O2 content of mycorrhizal plants submitted to drought stress is lower than in well watered treatments, suggesting that mycorrhization improves the plant’s oxidative stress response, although not via TcCAT-1 upregulation.
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Nanoparticles of betalamic acid derivatives with cyclodextrins. Physicochemistry, production characterization and stability
(Elsevier, 2020-07-14) Guerrero Rubio, Alejandra; Matencio Durán, Adrián; Gandía Herrero, Fernando; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular A
The use of betalains as bioactive compounds has been widely investigated. However, their use as a functional food requires a more exhaustive study because of their photosensitivity and poor stability. For this reason, this works studies the stabilization of two highly bioactive betalain derivatives, phenylethylamine-betaxanthin (Ph- Bx) and indoline-betacyanin (In-Bc) by nanoencapsulation in natural a modified cyclodextrins (CDs). Methyl- β-CD (Mβ-CD) showed the best results for Ph-Bx while Hydroxypropyl-β-CD (HPβ-CD) was better in the case of In- Bc. In addition, the effect of pH and temperature on encapsulation was studied finding that the encapsulation constant (KF) value increased as the pH decreased in the case of Ph-Bx but not in the case of In-Bc. The KF decreased as the temperatures increased. The thermodynamic parameters, ΔH◦, ΔS◦ and ΔG◦, were also calculated. Molecular docking provided further insight into how the different interactions influenced the encapsulation constant. The results show that the presence of CDs during the biotechnological synthesis of Ph-Bx and In- Bc increased production by 51 and 26%, respectively, and also increased the stability of both derivatives. This study represents a first step towards increasing the production of this type of compound for introduction into functional foods.
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Reversible bleaching of betalains induced by metals and application to the fluorescent determination of anthrax biomarker
(Elsevier, 2020-05-01) Guerrero Rubio, M. Alejandra; Martínez Zapata, Joaquín; Henarejos Escudero, Paula; Gandía Herrero, Fernando; García Carmona, Francisco; Bioquímica y Biología Molecular A
Betalains are antioxidant pigments of plant origin that are found in nature in the order Caryophyllales. They are classified into two groups: betacyanins, which present a violet coloration, and betaxanthins, fluorescent betalains with yellow coloration. In this work, the effect of metals, such as copper and europium, on the spectroscopic properties of betalains is studied. For the first time, the reversibility of spectral changes in fluorescence and absorbance is considered after the addition of chelating substances. These results explain the general bleaching of betalains by metals. The reversibility of the betalain-metal complexes is applied to the fluorescent detection of the presence of spores from Bacillus by the interaction of the complexes with the chelator dipicolinic acid, which is the main and characteristic component of endospores. This fast, economic method allows the detection of spores below the infective dose for anthrax by using a flower pigment present in Mirabilis jalapa.
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Inactivation of lipoxygenase and cyclooxygenase by natural betalains and semi-synthetic analogues
(Elsevier, 2014-01-13) Vidal, Pedro J.; Gandía Herrero, Fernando; López Nicolás, José Manuel; García Carmona, Francisco; Bioquímica y Biología Molecular "A"
Betalains are natural pigments characteristic of plants of the order Caryophyllales. In this work, the role of betalains in the anti-inflammatory activity described for plant extracts is analysed in terms of the inactivation of the enzymes involved in the biochemical response (lipoxygenase and cyclooxygenase). Pure natural betalains and semi-synthetic analogues are demonstrated to promote a significant reduction of the enzymes activity. Reactions were followed spectrophotometrically and by HPLC-DAD. Phenethylamine-betaxanthin was the most potent in the inactivation of cyclooxygenase, with a reduction of 32% of the control activity at 125 lM, while the natural pigment betanidin and a betalain analogue derived from indoline resulted as the most potent inactivators of lipoxygenase, with IC50 values of 41.4 and 40.1 lM, respectively. Molecular docking studies revealed that betalains interact with the lipoxygenase amino acids involved in substrate binding and with Tyr-385 and Ser-530 close to the yclooxygenase active site, interfering in enzyme catalysis.
Open Access
Light emission in betalains: from fluorescent flowers to biotechnological applications
(Cell Press, 2020-02) Guerrero Rubio, María Alejandra; Escribano Cebrián, Josefa; Gandía Herrero, Fernando; García Carmona, Francisco; Bioquímica y Biología Molecular A
The discovery of visible fluorescence in the plant pigments betalains revealed the existence of fluorescent patterns in flowers of plants of the order Caryophyllales, where betalains substitute anthocyanins. The serendipitous initial discovery led to a systemized characterization of the role of different substructures on the photophysical phenomenon. Strong fluorescence is general to all members of the family of betaxanthins linked to the structural property that the betalamic acid moiety is connected to an amine group. This property has led to bioinspired tailor-made probes and to the development of novel biotechnological applications in screening techniques or microscopy labeling. Here, we comprehensively review the photophysics, photochemistry, and photobiology of betalain fluorescence and describe all current applications.
Open Access
El legado del Catedrático Mario Honrubia García
(Universidad de Murcia, 2016) García Carmona, Francisco
Embargo
Production of dihydroxylated betalains and dopamine in cell suspension cultures of Celosia argentea var. plumosa
(American Chemical Society, 2015-03-01) Guadarrama-Flores, Berenice; Rodríguez-Monroy, Mario; Cruz-Sosa, Francisco; Gandía Herrero, Fernando; García Carmona, Francisco; Bioquímica y Biología Molecular "A"
Betalains are plant pigments of hydrophilic nature with demonstrated chemopreventive potential in cancer celllines and animal models. Among the betalains, those containing an aromatic moiety with two free hydroxyl groups possess thestrongest antioxidant and free radical scavenging activities. The betaxanthins dopaxanthin and miraxanthin V and the betacyaninsbetanidin and decarboxy-betanidin are the only natural betalains with catecholic substructures. These four pigments have beenproduced in cell cultures established from hypocotyls of the plant Celosia argentea. Two stable and diﬀerentially colored cell lines,yellow and red, were maintained on Murashige and Skoog medium supplemented with the plant growth regulators 6-benzylaminopurine (6.66 μM) and 2,4-dichlorophenoxyacetic acid (6.79 μM). Derived suspension cultures showed increasedproduction of dihydroxylated betalains in the cells and secreted to the medium with a maximum reached after 8 days of culture.In addition, precursor molecules betalamic acid and dopamine, with content up to 42.08 mg/g dry weight, were also obtained.The joint presence of the bioactive betalains together with the production of dopamine and betalamic acid show the ability of cellcultures of C. argentea to become a stable source of valuable phytochemicals
Embargo
Effect of industrial processing on amino acid content of broccoli
(Wiley, Society of Chemical Industry, 2001) Murcia Tomás, María Antonia; López Ayerra, Beatriz; Martínez Tomé, Magdalena; García Carmona, Francisco; Tecnología de Alimentos, Nutrición y Bromatología
The levels of amino acids in broccoli stems and florets before and after various blanching times (in the case of freezing) and after bottling have been studied to elucidate to what extent nutrient quality is affected by industrial processing. The following amino acids (mg kg-1 fresh weight) were identified by ion exchange chromatography in raw broccoli florets: glutamine (1338), proline (732), asparagine (578), valine (310), arginine (296), isoleucine (204), threonine (169), leucine (166), phenylalanine (159), aspartic acid (140), lysine (127), alanine (122), tyrosine (105), S-methylcysteine (96), histidine (89), ornithine (59), glutamic acid (44), -y-aminobutyric acid (31), glycine (11) and serine (0.2). Raw stems contained the same amino acids but at lower levels (p < 0.05). The levels of all these amino acids fell during both industrial processes studied (bottling and freezing after blanching for 60, 90, 120 and 150 s), particularly in the frozen samples (losses of 50-70% in the florets and 20-50% in the stems). In summary, losses of broccoli amino acids were lower if blanching times were kept short. The optimal blanching time at 94 C for florets and stems intended for freezing was 90 s, and this did not result in any great loss of nutritional value related to amino acid content. Bottled florets had greater nutritional value than those frozen after being exposed to the longest blanching times (120 and 150 s).
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Propiedades cinéticas de la actividad hidroxilante de tirosinasa /Francisco García Carmona ; Directores J. A. Lozano Teruel, Fcº García Cánovas.
(Murcia : Universidad,, 1980) García Carmona, Francisco