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(2331) Proposal to conserve the name Globulina boliviana (Bryoerythrophyllum bolivianum) against Trichostomum brunneum (Bryophyta: Pottiaceae)
(Wiley Online Library, 2014-12-01) Jiménez, Juan Antonio; Cano Bernabé, María Jesús; Alonso García, Marta; Biología Vegetal
Embargo
(2442) Proposal to conserve the name Tortula angustata (Chionoloma angustatum) against Syrrhopodon crispus (Bryophyta: Pottiaceae)
(Wiley Online Library, 2016-06-01) Alonso García, Marta; Jiménez, Juan A.; Cano, María J.; Biología Vegetal
Open Access
A molecular approach to the phylogeny of the moss genus Pseudocrossidium (Pottiaceae, Bryopsida) and its taxonomic implications
(Wiley, 2022-08-12) Cano, María J.; Jiménez, Juan A.; Gallego, M. Teresa; Guerra, Juan; Biología Vegetal
Pseudocrossidium is a genus of 21 species belonging to the Pottiaceae with the highest concentration of taxa and morphological variation found in South America. To investigate the evolutionary relationships among the species of Pseudocrossidium and other members of the Pottioideae, molecular phylogenetic reconstructions, using the nuclear ITS1‐5.8S‐ITS2, and the plastid atpB‐rbcL, trnG, and trnL‐F, has been performed because this genus has only been partially tested using molecular markers. Bayesian and maximum likelihood topologies show that the genus, as presently circumscribed, is polyphyletic. Consequently, the circumscription of Pseudocrossidium is amended and numerous taxonomic changes resulting from the molecular, morphological, and nomenclatural studies are proposed. The phylogenetic and morphologically divergent Pseudocrossidium mendozense is renamed as Gertrudiella mendozensis. Pseudocrossidium linearifolium and P. porphyreoneurum are representatives of the new genera Barbulastrum and Helicobarbula, respectively. Pseudocrossidium carinatum and P. santiagense are accommodated in a new genus Austrobarbula. Aloinella, nested in a paraphyletic Pseudocrossidium, is maintained at generic rank, apparently derived from Pseudocrossidium. Barbula integrifolia, B. riograndensis, and Tortula jaffuelii are transferred to Pseudocrossidium. The remaining species of Pseudocrossidium are maintained in this genus, pending further studies. Conflicts of the trees observed could be evidence of interspecific or intergeneric gene flow in various lineages in the Pottioideae.
Embargo
A multilocus phylogeny of the moss genus Didymodon and allied genera (Pottiaceae): generic delimitations and their implications for systematics
(Wiley, 2022-03-21) Jiménez, Juan A.; Cano, María J.; Guerra, Juan; Biología Vegetal
Didymodon s.l. is one of the largest genera in the moss family Pottiaceae, with about 122 species distributed in all continents. This, together with its high degree of morphological variation, has made it one of the taxonomically most challenging genera of Pottiaceae. Circumscription of Didymodon s.l. has been, and still is, controversial. To date, the only molecular study that has investigated the delimitation of the genus has been far from comprehensive (35 samples from 27 species), limited in geographical scope (mainly restricted to Europe), and based exclusively on ITS sequences. To evaluate the circumscription of Didymodon s.l. and its relationships with the allied genera Andinella, Gertrudiella, and Tridontium, we conducted phylogenetic analyses of DNA sequences for three plastid markers (atpB–rbcL, trnG, and trnL‐F) and one nuclear locus (ITS) for 335 samples representing 86 species of Didymodon s.l. (ca. 70%), and all taxa of the genera Andinella, Gertrudiella, and Tridontium. Individual markers and concatenated matrices were analyzed using maximum likelihood and Bayesian approaches. Our results indicate that Didymodon s.l. is not monophyletic, because Andinella, Gertrudiella, and Tridontium species are nested within it. Species of these four genera can be divided into eight well‐supported and morphologically distinct genera: Didymodon s.s., Geheebia, Gertrudiella, Husnotiella, Trichostomopsis, Tridontium, Vinealobryum, and Zanderella. In correspondence with the results presented, 38 new combinations, 10 new synonyms, and a new name are provided for those taxa where required, and lectotypes are designated for 13 names. A diagnostic key to the eight recognized genera is provided.
Embargo
A new combination in Pseudosymblepharis (Pottiaceae) from South and Central América
(Taylor and Francis Group, 2014-02-23) Alonso García, Marta; Jiménez, Juan Antonio; Cano Bernabé, María Jesús; Biología Vegetal
Trichostomum schlimii Müll.Hal., a neglected Colombian taxon, is transferred to the genus Pseudosymblepharis Broth. as Pseudosymblepharis schlimii (Müll.Hal.) comb. nov. The species, known only from the type locality in Santa Marta, Colombia, is newly reported for the moss floras of Bolivia, Brazil, Dominican Republic, Ecuador, Guiana, Peru, and Venezuela. It is described, lectotypified, illustrated, and mapped. Diagnostic characters, and distinction from one closely related American species within the genus are discussed. Trichostomum mollissimum (Broth. ex E.B.Bartram) H.A.Crum and Pseudosymblepharis guatemalensis (E.B.Bartram) B.H.Allen are reduced to the synonymy of Pseudosymblepharis schlimii.
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A new species of Chionoloma (Pottiaceae) from Central and South America with a key to Neotropical species of the genus
(BioOne Digital Library, 2017-09-05) Alonso García, Marta; Jiménez, Juan A.; Cano, María J.; Biología Vegetal
A new species of Chionoloma Dixon, C. fractum M.Alonso, M.J.Cano & J.A.Jiménez, is described from Central and South America (Argentina, Belize, Bolivia, Brazil, Colombia, Ecuador, Panama, Peru and Venezuela). The species is distinguished morphologically by lanceolate or linear leaves, with apices usually broken, leaf margins strongly sinuous, basal marginal cells forming a V-shaped pattern, dorsal surface cells of the costa quadrate-round and papillose toward apex, costa percurrent or excurrent in a short mucro and central strand present. Drawings and light microscope photographs of the new species are provided. Moreover, the principal distinctive characters that separate it from the nearest species of Chionoloma are discussed and a key to Neotropical species of the genus is provided.
Embargo
A rational approach to improving the biotechnological production of taxanes in plant cell cultures of Taxus spp.
(Elsevier, 2014-03-27) Cusido, Rosa M.; Onrubia, Miriam; Sabater Jara, Ana Belén; Moyano, Elisabeth; Bonfill, Mercedes; Goossens, Alain; Pedreño, María Angeles; Palazón, Javier; Biología Vegetal
Taxol is a complex diterpene alkaloid scarcely produced in nature and with a high anticancer activity. Biotechnological systems for taxol production based on cell cultures of Taxus spp. have been developed, but the growing commercial demand for taxol and its precursors requires the optimization of these procedures. In order to increase the biotechnological production of taxol and related taxanes in Taxus spp. cell cultures, it is necessary not only to take an empirical approach that strives to optimize in-put factors (cell line selection, culture conditions, elicitation, up-scaling, etc.) and out-put factors (growth, production, yields, etc.), but also to carry out molecular biological studies. The latter can provide valuable insight into how the enhancement of taxane biosynthesis and accumulation affects metabolic profiles and gene expression in Taxus spp. cell cultures. Several rational approaches have focused on studying the transcriptomic profiles of key genes in the taxol biosynthetic pathway in Taxus spp. cell cultures treated with elicitors such as methyl jasmonate, coronatine and cyclodextrins in relation with the taxane pattern, production and excretion to the culture medium. These studies have provided new insights into the taxol biosynthetic pathway and its regulation. Additionally, identifying genes with low levels of expression even in the presence of elicitors, together with metabolomics studies, has shed light on the limiting steps in taxol biosynthesis and could help define suitable metabolic targets for engineering with the main aim of obtaining highly productive Taxus cultured cells. In this review, we have summarized the latest endeavors to enhance the molecular understanding of the action mechanism of elicitors in Taxus spp. cell cultures. Developments in the ongoing search for new and more effective elicitation treatments and the application of metabolic engineering to design new transgenic cell lines of Taxus with an improved capacity for taxane production are described.
Open Access
A smart strategy to Improve t-Resveratrol production in grapevine cells treated with Cyclodextrin polymers coated with magnetic nanoparticles
(MDPI, 2020-04-24) Almagro Romero, Lorena; Gea Abellán, Alicia de; Rodríguez López, Marïa Isabel; Núñez Delicado, Estrella; Gabaldón, José Antonio; Pedreño, María Ángeles; Biología Vegetal
One of the most successfully procedures used to increase the production of t-resveratrol in Vitis vinifera suspension-cultured cells is the application of cyclodextrins (CDs) and methyl jasmonate (MJ) as elicitors. In particular, β-CDs are characterized by their chemical structure which makes them special, not only by acting as elicitors, but also because they are compounds capable of trapping high added-value hydrophobic molecules such as t-resveratrol. However, the use of β-CDs as elicitors increases the production costs of this compound, making their industrial exploitation economically unfeasible. Therefore, the development of β-CDs recovery strategies is necessary to provide a viable solution to their industrial use. In this work, carboxymethylated and hydroxypropylated β-CDs have been used to form polymers using epichlorohydrin (EPI) as a cross-linking agent. The polymers were coated to Fe3O4 nanoparticles and were jointly used with MJ to elicit V. vinifera suspension-cultured cells. Once elicitation experiments were finished, a magnet easily allowed the recovery of polymers, and t-resveratrol was extracted from them by using ethyl acetate. The results indicated that the production of t-resveratrol in the presence of free carboxymethyl-β-CDs was much lower than that found in the presence of carboxymethyl-β-cyclodextrins-EPI polymer coated magnetic nanoparticles. In addition, the maximal levels of t-resveratrol were found at 168 h of elicitation in the presence of 15 g/L hydroxypropyl-β-CDs polymer coated magnetic nanoparticles and MJ, and non-t-resveratrol was found in the extracellular medium, indicating that all the t-resveratrol produced by the cells and secreted into the culture medium was trapped by the polymer and extracted from it. This work also showed that polymers can be regenerated and reused during three cycles of continuous elicitation since the induction and adsorption capacity of hydroxypropyl-β-CDs polymer-coated magnetic nanoparticles after these cycles of elicitation remained high, allowing high concentrations of t-resveratrol to be obtained.
Open Access
Algas aerofíticas epipélicas del Marjal de Pego-Oliva, este de la Península Ibérica
(2011) García Fernández, María Eugenia; Sánchez Lorencio, María Isabel; Aboal Sanjurjo, Marina; Biología Vegetal
Embargo
Alterations in the silymarin metabolism in transgenic Silybum marianum cultured cells by the heterologous expression of the Arabidopsis thaliana V-myb myeloblastosis viral oncogene homolog transcription factor MYB12 and Cicer arietinum chalcone synthase
(Elsevier, 2020-11-01) Villar, David; Almagro Romero, Lorena; Palazón, Javier; Corchete, Purificación; Biología Vegetal
Silymarin (Sm), the main bioactive principle of Silybum marianum (L.) Gaernt. fruits, has strong antihepatotoxic properties and also exhibits antitumor and antiviral activity. This flavonolignan complex is synthesized from the flavonoid precursor taxifolin, which undergoes an oxidative coupling with the monolignol coniferyl alcohol. Attempts to produce Sm in plant cell suspensions have met with limited success, probably due to insufficient flux into the flavonoid branch pathway of Sm biosynthesis. In this study, it was attempted to increase Sm production in in vitro cultures of S. marianum by genetically engineering the flavonoid pathway. Using Agrobacterium tumefaciens strain C58C1, S. marianum cell suspension cultures were transformed either with the Arabidopsis thaliana transcription factor AtMYB12 (V-myb myelo-blastosis viral oncogene homolog) (MYB) or with a chalcone synthase (CHS) gene from Cicer arietinum. A double transformant was also generated by introducing the CaCHS gene in AtMYB12-expressing cultures. The ectopic expression of AtMYB12 in cultures activated some of the genes involved in the flavonoid pathway, notably chalcone isomerase (CHI) and flavonoid 3′-hydroxylase (F3’H), whereas the secondary metabolites al-tered by the inserted gene were chlorogenic acid glycoside derivatives. Expression of CaCHS in the cultures led to the production of the flavanone naringenin (Ng), which accumulated as glycosides. The simultaneous ex-pression of AtMYB12-CaCHS resulted in the production of lower amounts of chlorogenic derivatives but similar levels of Ng glycosides compared with the CaCHS lines. Both CaCHS lines and the double transformant could be maintained over prolonged subcultures without Ng production losses, confirming long-term and stable CaCHS transgene expression. In no case did the inserted genes have a discernable effect on Sm production compared with the un-transformed cultures, neither under control culture conditions or in cultures elicited with MeJA.
Open Access
Bacterial community of reindeer lichens differs between northern and southern lichen woodlands
(Canadian Science Publishing, 2022-01-18) Alonso García, Marta; Villarreal A., Juan Carlos; Biología Vegetal
Lichens cover nearly 7% of the earth’s surface, and in eastern Canada, lichen woodlands occupy over 300 000 km2. Reindeer lichens (genus Cladonia) are the main component of lichen woodlands and they play a crucial role in boreal forest ecology. We study, for the first time, the bacterial community of four species of reindeer lichens from eastern North America’s boreal forests. Using the 16S rRNA gene, we characterize the bacterial community of 189 lichen samples. We aim to analyse the effect of geography and host identity in the bacterial community composition and structure, verify the presence of a common core bacteria, and identify the most abundant core taxa. Our results suggest that host-lichen identity does not determine bacterial community composition and structure in reindeer lichens, but we confirm the influence of geography in shaping the diversity and abundance of bacteria associated with Cladonia stellaris. We also reveal that reindeer lichens share a reduced common core bacteria composed exclusively by Alphaproteobacteria. Northern lichen woodlands exhibit a significantly higher diversity and abundance of bacteria associated with C. stellaris than southern lichen woodlands do. The presence of the species Methylorosula polaris in the core bacteria is evident and may have a particular importance for reindeer lichens.
Open Access
Beneficial native bacteria improve survival and mycorrhization of desert truffle mycorrhizal plants in nursery conditions
(Springer, 2016-06-04) Navarro-Ródenas, Alfonso; Berná Amorós, Luis Miguel; Lozano-Carrillo, Cecilia; Andrino, Alberto; Morte Gómez, María Asunción; Biología Vegetal
Sixty-four native bacterial colonies were isolated from mycorrhizal roots of Helianthemum almeriense colonized by Terfezia claveryi, mycorrhizosphere soil, and peridium of T. claveryi to evaluate their effect on mycorrhizal plant production. Based on the phylogenetic analysis of the 16S rDNA partial sequence, 45 different strains from 17 genera were gathered. The largest genera were Pseudomonas (40.8 % of the isolated strains), Bacillus (12.2 % of isolated strains), and Varivorax (8.2 % of isolated strains). All the bacteria were characterized phenotypically and by their plant growth-promoting rhizobacteria (PGPR) traits (auxin and siderophore production, phosphate solubilization, and ACC deaminase activity). Only bacterial combinations with several PGPR traits or Pseudomonas sp. strain 5, which presents three different PGPR traits, had a positive effect on plant survival and growth. Particularly relevant were the bacterial treatments involving auxin release, which significantly increased the root-shoot ratio and mycorrhizal colonization. Moreover, Pseudomonas mandelii strain 29 was able to considerably increase mycorrhizal colonization but not plant growth, and could be considered as mycorrhiza-helper bacteria. Therefore, the mycorrhizal roots, mycorrhizosphere soil, and peridium of desert truffles are environments enriched in bacteria which may be used to increase the survival and mycorrhization in the desert truffle plant production system at a semi-industrial scale.
Open Access
Bioactivity and bioavailability of phytoene and strategies to improve its production
(SPRINGER, 2018-12-12) Miras-Moreno, B.; Pedreño García, María Ángeles; Almagro, L.; Biología Vegetal
Embargo
Bioactivity of phytosterols and their production in plant in vitro cultures
(American Chemical Society, 2016-09-12) Miras Moreno, Begoña; Sabater Jara, Ana Belén; Pedreño, María Angeles; Almagro, Lorena; Biología Vegetal
Phytosterols are a kind of plant metabolite belonging to the triterpene family. These compounds are essential biomolecules for human health, and so they must be taken from foods. β-Sitosterol, campesterol, and stigmasterol are the main phytosterols found in plants. Phytosterols have beneficial effects on human health since they are able to reduce plasma cholesterol levels and have antiinflammatory, antidiabetic, and anticancer activities. However, there are many difficulties in obtaining them, since the levels of these compounds produced from plant raw materials are low and their chemical synthesis is not economically profitable for commercial exploitation. A biotechnological alternative for their production is the use of plant cell and hairy root cultures. This review is focused on the biosynthesis of phytosterols and their function in both plants and humans as well as the different biotechnological strategies to increase phytosterol biosynthesis. Special attention is given to describing new methodologies based on the use of recombinant DNA technology to increase the levels of phytosterols.
Open Access
Biotechnological approach to increase oxyresveratrol production in mulberry in vitro plants under elicitation
(MDPI, 2023-01-25) Sabater Jara, Ana Belén; Almagro, Lorena; Nicolás Sánchez, Isabel; Pedreño, María Angeles; Biología Vegetal
Morus alba L. is used for a range of therapeutic purposes in Asian traditional medicine, and its extracts are reported to be effective against lipidemia, diabetes, and obesity, as well as being hepatoprotective and tyrosinase-inhibitory. They are also included in cosmetic products as anti-aging and skin-whitening agents. Stilbenes, the major bioactive compounds found in M. alba, have received renewed attention recently because of their putative activity against COVID-19. In this study M. alba plants were established in vitro, and the effect of elicitation on plant growth and stilbene accumulation, specifically oxyresveratrol and trans-resveratrol, was investigated. Different concentrations of the elicitors including methyl jasmonate and cyclodextrins were applied, and stilbene levels were determined in leaves, roots, and the culture medium. Elicitation of the M. alba plants with 5 mM cyclodextrins, alone or in combination with 10 µM methyl jasmonate, significantly increased the total phenolic content in the culture medium and leaves after 7 days of treatment. The higher total phenolic content in the roots of control plants and those treated only with methyl jasmonate indicated that cyclodextrins promoted metabolite release to the culture medium. Notably, the cyclodextrin-treated plants with the highest levels of oxy- and trans-resveratrol also had the highest total phenolic content and antioxidant capacity. These results indicate that elicited M. alba in vitro plants constitute a promising alternative source of bioactive stilbenes to supply pharmaceutical and cosmeceutical industries.
Embargo
Biotechnological approaches to enhance the biosynthesis of ginkgolides and bilobalide in Ginkgo biloba
(Springer, 2013-02-09) Sabater Jara, Ana Belén; Souliman Youssef, Sabry; Novo Uzal, Esther; Almagro, Lorena; Belchí Navarro, Sarai; Pedreño, María Ángeles; Biología Vegetal
Ginkgo biloba is one of the oldest living tree species and its extracts or powdered leaves are one of the best selling herbal preparations. The main bioactive constituents are flavonoids and the terpene trilactones, ginkgolides and bilobalide, which are responsible for their pharmacological activity. However, there are many difficulties for ginkgo leaves supply and the chemical synthesis is far from of being applicable for commercial-scale production. G. biloba cell cultures have arisen as a useful alternative source of pharmacologically active terpene trilactones. This review sheds light on the chemistry and biosynthesis of terpene trilactones with the aim of increasing the production of these high value compounds by biotechnological approaches. Different biotechnological strategies to improve ginkgolides and bilobalide production will be discussed, including screening and selection of in vitro ginkgo cultures, cell differentiation levels of these cultures, optimization of culture conditions, feeding and elicitation strategies. Special attention will be paid in developing new methodologies to enhance ginkgo cell biomass and provide high amounts of these bioactive terpene trilactones using large-scale cell cultures.
Embargo
Biotechnological production of β‑carotene using plant in vitro cultures
(Springer, 2022-07-14) Almagro, Lorena; Correa Sabater, José Manuel; Sabater Jara, Ana Belén; Pedreño, María Angeles; Biología Vegetal
β-carotene is an orange carotenoid often found in leaves as well as in fruits, flowers, and roots. A member of the tetraterpene family, this 40-carbon isoprenoid has a conjugated double-bond structure, which is responsible for some of its most remarkable properties. In plants, β-carotene functions as an antenna pigment and antioxidant, providing protection against photooxidative damage caused by strong UV-B light. In humans, β-carotene acts as a precursor of vitamin A, prevents skin damage by solar radiation, and protects against several types of cancer such as oral, colon and prostate. Due to its wide spectrum of applications, the global market for β-carotene is expanding, and the demand can no longer be met by extraction from plant raw materials. Considerable research has been dedicated to finding more efficient production alternatives based on biotechnological systems. This review provides a detailed overview of the strategies used to increase the production of β-carotene in plant in vitro cultures, with particular focus on culture conditions, precursor feeding and elicitation, and the application of metabolic engineering.
Open Access
Broccoli byproduct extracts attenuate the expression of UVB-induced proinflammatory cytokines in HaCaT keratinocytes
(MDPI, 2024-12-02) Borja Martínez, María; Pedreño, María Angeles; Sabater Jara, Ana Belén; Biología Vegetal
Broccoli byproducts are an important source of bioactive compounds, which provide important benefits for human skin due mainly to their antioxidant and anti-inflammatory properties. The primary target of UVB radiation is the basal layer of cells in the epidermis, with keratinocytes being the most abundant cell population in this layer. Given the wide range of side effects caused by exposure to UVB radiation, reducing the amount of UV light that penetrates the skin and strengthening the protective mechanisms of the skin are interesting strategies for the prevention of skin disorders. This work aims to evaluate the protective mechanisms triggered by broccoli by-products extract (BBE) on HaCaT keratinocytes exposed to UVB radiation as well as the study of the regenerative effect of these extracts on the barrier of skin keratinocytes damaged by superficial wounds as a strategy to revalorize this agricultural waste. The results obtained revealed that the BBEs exhibited a high cytoprotective effect on the HaCaT exposed to UVB light, allowing it to effectively reduce the intracellular content of ROS, as well as effectively attenuating the increase in proinflammatory cytokines (IL-1β, IL-6, IL-78, TNF-α) and COX-2 induced by this type of radiation. Furthermore, the BBE could be an excellent regenerative agent for skin wound repair, accelerating the migration capacity of keratinocytes thus contributing to the valorization of this byproduct as a valuable ingredient in cosmetic formulations.
Embargo
Bryoerythrophyllum sollmanianum (Pottiaceae), a new moss species from the Sino-Himalayan region
(The American Bryological and Lichenological Society, 2019-07-12) Jiménez, Juan A.; Cano, María J.; Shevock, James; Biología Vegetal
Bryoerythrophyllum sollmanianum J.A.Jiménez, M.J.Cano & Shevock is described and illustrated as a new species from the Sino-Himalayan region of China, Nepal and India. The species is corticolous, and easily distinguished from all its congeners in having stems with cluster of deciduous flagellate branchlets. Additionally, it is characterized by its lingulate leaves with apiculate apices, plane and regularly dentate margins above midleaf, costa ending below the apex, papillose basal cells that are not differentiated from the upper cells, and a rudimentary peristome. Its distinction from, and relationships with, similar species within the genus are discussed. Distribution of the new species is mapped.
Open Access
Changes in the secretome of Vitis vinifera cv. Monastrell cell cultures treated with cyclodextrins and methyl jasmonate
(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2019-02) Belchí Navarro, Sarai; Almagro, L.; Bru, R.; Pedreño García, María Ángeles; Biología Vegetal

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