Air-borne xylene degradation by Bougainvillea buttiana and the role of epiphytic bacteria in the degradation.

The efficiency of xylene removal from contaminated air by thirteen perennial plants was studied. The results showed that Bougainvillea buttiana had the highest xylene removal efficiency. Different parts of B. buttiana such as stems, epicuticular waxes, and plant stomata (including microorganism-associated plant leaves) can uptake xylene 53.1±1.9%, 32.3±0.9, and 14.6±0.0%, respectively. Metabolite products found in treated plants may result from stress or defense compounds triggered by exposure to xylene. Moreover, possible degradation products in B. buttiana stems were analyzed after treatment with xylene at 100 ppm. Various metabolites in B. buttiana stems such as 2,6-dimethoxyphenol, 4-hydroxy-3,5-dimethoxy benzoic acid, 1-isopropyl-4-methylbenzene, p-tolualdehyde, 2,5-dimethoxy-4-methylbenzaldehyde, 2,4-dihydroxy-2,5-dimethyl-3(2H)-furanone, 3-methyl-2-butenal, dihydroxy acetone, propanedial, and many organic acids are related to the xylene degradation pathway. In addition, microorganism-associated B. buttiana leaves especially Enterobacter cloacae LSRC11, Staphylococcus sp. A1 and Pseudomonas aeruginosa enhanced the plant resulting in quicker xylene removal.

Advances in Boerhaavia diffusa hairy root technology: a valuable pursuit for identifying strain sensitivity and up-scaling factors to refine metabolite yield and bioactivity potentials.

The present study reports the Agrobacterium rhizogenes-mediated hairy root induction in of an ethno-medicinally significant herb-Boerhaavia diffusa L., for elucidating the underlying competence regarding its biosynthetic (i.e. boeravinone B and eupalitin) and bioactivity (antibacterial, antioxidant and anti-inflammatory) potentials. Host plant-specific receptiveness towards A. rhizogenes strains and disparity in compatibility threshold of leaf and nodal explants were evident. Only leaf explants responded, attaining hairy root induction with the ATCC 15834 followed by A4 and SA79 strains in reducing order of transformation efficiency. The growth behaviours differed amongst independent rhizoclones, and two clones of A4 (RBH) and ATCC 15834 (RBT8) origin demonstrated higher growth potentials. Polymerase chain reaction amplification of rol genes confirmed their transformed nature. Optimization of the appropriate solvent and reverse phase high-performance liquid chromatography parameters relating to the targeted metabolite production in the selected RBH and RBT8 clones revealed higher accumulation of eupalitin with the RBH clone having the best result of 1.44 times greater yield over the control root. Compared to the selected rhizoclones, the control roots however showed higher boeravinone B content. Devising a modified "stirred-tank" reactor through equipping with marine impellers and ring spargers facilitated high-density RBH root biomass yield with 6.1-fold and 1.15-fold yield increment of the boeravinone B and eupalitin respectively compared to shake-flask cultures. Considering the control roots, the RBH clone revealed analogous antioxidant/antibacterial activities with improved anti-inflammatory potential. The hairy root mediated higher production of boeravinone B and eupalitin could be achieved for the first time in bioreactor.

Phylogenetic trait conservation in the partner choice of a group of ectomycorrhizal trees.

Ecological interactions are frequently conserved across evolutionary time. In the case of mutualisms, these conserved interactions may play a large role in structuring mutualist communities. We hypothesized that phylogenetic trait conservation could play a key role in determining patterns of association in the ectomycorrhizal symbiosis, a globally important trophic mutualism. We used the association between members of the pantropical plant tribe Pisonieae and its fungal mutualist partners as a model system to test the prediction that Pisonieae-associating ectomycorrhizal fungi will be more closely related than expected by chance, reflecting a conserved trait. We tested this prediction using previously published and newly generated sequences in a Bayesian framework incorporating phylogenetic uncertainty. We report that phylogenetic trait conservation does exist in this association. We generated a five-marker phylogeny of members of the Pisonieae and used this phylogeny in a Bayesian relaxed molecular clock analysis. We established that the most recent common ancestors of Pisonieae species and Pisonieae-associating fungi sharing phylogenetic conservation of their patterns of ectomycorrhizal association occurred no more recently than 14.2 Ma. We therefore suggest that phylogenetic trait conservation in the Pisonieae ectomycorrhizal mutualism association represents an inherited syndrome which has existed for at least 14 Myr.

Los "equibióticos" ni combate ni Resistencia / The "equibiotics": no combato resistance

Investigando las propiedades de plantas que suelen ser usadas con propósitos anti-infecciosos en las medicinas populares, postulamos que la acción de ciertas combinaciones de extractos con acción antimicrobiana se da a la par de un efecto de preservación y fortalecimiento del equilibrio normal de la microbiota local en el huésped. A tales fitomedicamentos proponemos denominarlos "equibióticos" (que equilibran la microbiota) y a las dos vías de actuación bajos las que actúan: "auferobiótica" (que inactiva a los microorganismos patógenos) y "alerebiótica" (que protege y reconstruye la conformación normal de la microbiota). Estos productos formarían parte de la nueva tendencia en la búsqueda de fitomedicamentos para detener y prevenir las infecciones, sustentada en un nuevo marco de referencia teóric-práctico en el que la recuperación del equilibrio de la microbioma del huésped suplanta a la idea de exterminación microbiana, generalmente aceptada en otros tiempos(AU)

Investigating the properties of plants often used in traditional medicines for anti.infective purposes, we postúlate the action of certain combinations of extracts that possess antimicrobial properties together with effects on the preservation and strengthening of the normal balance of the host microbiota. For such herbal medicines we propose the term "equibiotics" (that balance the microbiota), and to their two models of action :"auferobiotics" (that inactivate pathogens) and "alerebiotics" (that protect and restore the balance of the biota). Equibiotics have the peculiarity that their bimodal action influences and strengthens the natural ability of the host to regulate the microbiota. These products belong to the global new trend in the search for herbal medicinal products for stopping and preventing infections, based on a new theoretical and practical framework in which the recovery of the balance of the host microbiome substitutes, as goal, the idea of extermination of pathogens, generally accepted in the past(AU)

Edaphic factors do not govern the ectomycorrhizal specificity of Pisonia grandis (Nyctaginaceae).

Pisonia grandis (Nyctaginaceae), a widespread tree of Pacific coral atolls and islands, displays one of the more restrictive ranges of ectomycorrhizal (ECM) fungus associates among autotrophic plants. Only five ECM fungi are currently known associates; our study adds one. In many habitats, P. grandis is restricted to large seabird colonies where nitrogen and phosphorus inputs in the form of guano are substantial. It has been suggested that the ECM specificity displayed by P. grandis is the result of the unusual nutrient-rich habitat in which P. grandis grows. On Rota, Commonwealth of the Northern Mariana Islands, P. grandis grows in habitats heavily influenced by guano additions and also in upland forests where seabirds do not roost or nest. To test the hypothesis that the ECM specificity displayed by P. grandis is the result of nutrient-related or toxicity-related factors associated with guano inputs, we sampled P. grandis growing in both guano-rich and guano-poor habitats on Rota, Commonwealth of the Northern Mariana Islands. We identified ECM symbionts of P. grandis from both habitats as well as two symbionts of Intsia bijuga (Fabaceae) from nutrient-rich habitats. We identified three ECM symbionts of P. grandis from Rota; all three were found in both guano-rich and guano-poor habitats. No differences in community diversity were detected between guano-rich and guano-poor habitats. We also detected two ECM fungal species associating with I. bijuga but not associating with P. grandis inside guano-rich habitats. From these results, we infer that edaphic factors are not responsible for limiting the ECM community associating with P. grandis to its observed level of specificity.

Inocybe tauensis, a new species from the Samoan Archipelago with biogeographic evidence for a Paleotropical origin.

Inocybe tauensis is described as a new species from the island of Ta'u, American Samoa. The species occurs in native littoral forest and is associated with the ectomycorrhizal tree Pisonia grandis. Based on an analysis of nLSU, RPB1, and RPB2 sequence data, I. tauensis appears to be derived from ancestors with a Paleotropical biogeographical distribution. Alternative explanations for the unexpected presence of an Inocybe species in the Samoan Archipelago are discussed.

Mycorrhizal symbionts of Pisonia grandis and P. sechellarum in Seychelles: identification of mycorrhizal fungi and description of new Tomentella species.

Nyctaginaceae includes species that are predominantly non-mycorrhizal or form arbuscular or ectomycorrhiza. Root-associated fungi were studied from P. grandis and P. sechellarum roots collected respectively on the islands of Cousin and Silhouette in Seychelles. In addition fungal sporocarps were collected from the sampling area. Fungal symbionts were identified from the roots by anatomotyping and rDNA sequencing; sporocarps collected were examined microscopically and sequenced. Three distantly related ectomycorrhizal fungal species belonging to Thelephoraceae were identified from the roots of P. grandis. Sporocarps also were found for two symbionts and described as new Tomentella species. In addition Tomentella species collected from other Seychelles islands were studied and described as new species if there was no close resemblance to previously established species. P. sechellarum was determined to be an arbuscular mycorrhizal plant; three arbuscular mycorrhizal fungal species were detected from the roots. P. grandis is probably associated only with species of Thelephoraceae throughout its area. Only five Tomentella species are known to form ectomycorrhiza with P. grandis and they never have been found to be associated with another host, suggesting adaptation of these fungi to extreme environmental conditions in host's habitat.

Ectomycorrhizal mycobionts of Pisonia grandis on coral cays in the Capricorn-Bunker group, Great Barrier Reef, Australia.

The diversity of ectomycorrhizal mycobionts of Pisonia grandis (Nyctaginaceae) from coral cays in the Capricorn-Bunker group, Great Barrier Reef, Australia, was examined. Only two ectomycorrhiza morphotypes (brown and black) were identified in soil from seven cays and DNA from both morphotypes was subjected to ITS-RFLP and sequence analysis. The brown morphotype was present in soil from all cays but the black morphotype was only observed in soil from three cays. ITS-RFLP analysis showed that the brown and black morphotypes were formed by different fungal taxa, with the RFLP pattern for the black morphotype being consistent with that of the culture previously obtained from black ectomycorrhizal roots on Heron Island. Comparison with the GenBank database revealed that closest matches to both morphotypes were sequences for various Thelephoraceae (Basidiomycota), but the brown and black morphotypes had only 80% sequence similarity to each other. Neighbour-joining analysis of these sequences with sequences for other Thelephoraceae grouped the brown and black morphotypes in a well-supported clade with several Tomentella species, suggesting that both belong to this genus. The data are discussed in relation to ectomycorrhizal fungal diversity and the coral cay habitat.

Russulaceae and Thelephoraceae form ectomycorrhizas with members of the Nyctaginaceae (Caryophyllales) in the tropical mountain rain forest of southern Ecuador.

* Three members of the Nyctaginaceae, two Neea species and one Guapira species, occurred scattered within a very species-rich neotropical mountain rain forest. The three species were found to form ectomycorrhizas of very distinctive characters, while all other tree species examined formed arbuscular mycorrhizas. * The ectomycorrhizas were structurally typified according to light and transmission electron microscope investigations. The internal transcribed spacer (ITS) rDNA and part of the nuclear large subunit (LSU, 28S) rDNA of the mycorrhiza forming fungi were amplified and sequenced. Phylogenetic analyses were carried out. * Neea species 1 was found to form typical ectomycorrhizas with five different fungal species, Russula puiggarii, Lactarius sp., two Tomentella or Thelephora species, and one ascomycete. Neea species 2 and the Guapira species were associated with only one fungus each, a Tomentella/Thelephora species clustering closely together in an ITS-neighbour-joining tree. The long and fine rootlets of the Guapira species showed proximally a hyphal mantle and a Hartig net, but distally intracellular fungal colonization of the epidermis and root hair development. The ectomycorrhizal segments of the long roots of Neea species 2 displayed a hyphal mantle and a Hartig net around alive root-hair-like outgrowths of the epidermal cells. * The distribution and the evolution of ectomycorrhizas in the predominantly neotropic Nyctaginaceae are discussed.