The aim of this study was to evaluate the analgesic effect of the methanolic extract from callus culture of Phyllanthus tenellus, P. corcovadensis and P. niruri in several models of pain in mice. The extracts (medium containing 2,4-dichlorophenoxyacetic acid) of P. corcovadensis, P. niruri and P. tenellus (3-90 mg kg-1, i.p.) caused graded inhibition of abdominal constrictions induced by acetic acid (0.6%), with ID50 (i.e. dose that reduced response of control by 50%) values of about 30, 19 and > 30 mg kg-1, respectively. The extract of callus of Phyllanthus obtained in indole-3-butyric acid and indole-3-acetic acid media (3-90 mg kg-1, i.p.) caused a similar analgesic effect. In the formalin test, the extract of P. tenellus obtained in indole butyric acid medium (3-100 mg kg-1, i.p.) inhibited only the second phase of formalin-induced pain with an ID50 value of about 100 mg kg-1. Both the indole acetic acid and indole butyric acid methanolic extracts of P. tenellus and P. corcovadensis (10-100 mg kg-1, i.p.) dose-dependently inhibited both phases of formalin-induced pain (ID50 values for the second phase were approx. 100 and 52 mg kg-1, respectively). However, the extract of callus from Phyllanthus failed to affect formalin-induced paw oedema, as well as the response to radiant heat in the tail-flick test. In addition, the analgesic effect of morphine, but not the analgesic effects caused by Phyllanthus callus extract, was fully antagonized by naloxone.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of this work was to study morphological and biochemical aspects during zygotic embryogenesis in O. catharinensis, by measuring changes in the endogenous concentrations of proteins, amino acids, polyamines (PAs), indole-3-acetic acid (IAA) and abscisic acid (ABA). Buffer-soluble and insoluble protein contents were determined by spectrometry, and amino acids, PAs, IAA and ABA concentrations were determined by high performance liquid chromatography. Total amino acid accumulation, predominantly asparagine, occurred when the embryo showed completely developed cotyledons, with posterior reduction in the mature embryo. This decrease in total amino acid concentration in the mature embryo may result from their use in storage as well as for LEA protein synthesis. Free putrescine (Put) concentration decreased, while free spermine (Spm) increased during embryo development. This suggest a role for Put in the initial phases of embryogenesis when high rates of cell division occur, while elevated concentration of Spm are essential from the middle to the end of embryo development, when growth is mainly due to cell elongation. An IAA peak in zygotic embryos occurred during initial development, suggesting a link between growth and cellular division as well as with the establishment of bilateral symmetry. ABA concentration declined during initial stages of development then increased at the mature embryo stage, suggesting a possible relationship with dormancy and recalcitrance characteristics. Our results show that changes in the phytohormones (IAA, ABA and PAs) concentrations in combination with amino acids are likely important factors determining the developmental stages of O. catharinensis zygotic embryos.

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The Brazilian biomes (Amazon, Atlantic Forest, Cerrado, Caatinga, Pantanal, and Pampa) comprise one of the highest levels of plant diversity in the world; however, non-sustainable practices, deforestation, and land use have resulted in significant losses and fragmentation of the native forests. These ecosystems are now threatened and protection of their native plants through ex situ conservation is an urgent necessity. Cryopreservation and in vitro conservation are complementary options for securing and protecting Brazil's native plant species because their potential economic value is critically important to develop strategies that will (1) support their sustainable utilization, (2) protect against the over-exploitation of species growing in natural habitats, and (3) conserve the genetic diversity of germplasm from species of different provenances. Biotechnological approaches will help to address future economic and environmental demands placed upon already at-risk species. Conserving seed germplasm ex situ provides an additional safeguard against the risks (e.g., loss due to disease, climate change) of field conservation. Moreover, seed banks and cryobanks permit the long-term conservation of a wider genetic base; this offsets the labor and space intensive costs of conserving in the active growing state. This paper is a compilation of the current status of strategies applied for conserving Brazilian native plant species.

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A successful system of somatic embryogenesis is described for the forest tree Ocotea catharinensis Mez., which used mature zygotic embryo explants cultured on a modified Murashige and Skoog (MS) medium with activated charcoal, at 25°C in the dark. A medium composed of MS supplemented with 2% (w/v) sucrose, 0.3% (w/v) activated charcoal (AC), 362 p,M 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.8% (w/v) Technical Agar Grade III was used for multiplication of embryogenic cultures. Development up to the globular-stage was achieved using Lloyd and McCown woody plant medium (WPM) with 2.0% sucrose, 0.3% AC, 181 IxM 2,4-D and 0.8% Technical Agar Grade III. Significant effects of media pH on differentiation of early pro-embryogenic Ocotea cell aggregates were found. Low pH of media (ca.3-4) appeared to prevent differentiation of proembryogenic cell aggregates whereas higher pH levels (ca. 5-5.5) favoured the formation of globular structures. Once globular structures formed, they developed further to form cotyledonary somatic embryos, under the same set of culture conditions. Successful conversion of these somatic embryos to plantlets was achieved after culture on a medium composed of 1-strength WPM (minerals only) with 2% sucrose, 0.3% AC, 0.8% Technical Agar Grade III and 90.5 p.M 2,4-D, followed by transfer to a medium composed of ½-strength WPM (minerals only) with 2% sucrose, 0.8% Technical Agar Grade III and 0.905 txM 2,4-D and 1.4 txM gibberellic acid, in a 16-h photoperiod regime.

Foram isoladas de extratos de folhas de Ocotea catharinensis Mez (Lauraceae) quatorze neolignanas sendo nove benzofurânicas (incluindo três novas substâncias 1e, 2f e 4b), uma secobenzofurânica inédita (3b), duas biciclo[3.2.1]octânicas (incluindo a nova 5c), dois novos dímeros biciclo[3.2.1]octânicos (7a e 7b) e ainda dois sesquiterpenos (incluindo o novo humulanol 9). Nos embriões somáticos de O. catharinensis foram identificadas sete neolignanas incluindo uma nova neolignana biciclo[3.2.1]octânica (4a).The extracts from leaves of Ocotea catharinensis Mez (Lauraceae) were found to contain fourteen neolignans and two sesquiterpenes: nine benzofuran types (including three new compounds 1e, 2f and 4b), one new seco-benzofuran type (3b), two bicyclo[3.2.1]octane types (including the new compound 5c), two new dimers of bicyclo[3.2.1]octane type (7a and 7b) and two sesquiterpenes (including a new humulanol 9). In addition, seven neolignans were also showed to occur in somatic embryos of O. catharinensis including one new bicyclo[3.2.1]octane type (4a). Keywords:Ocotea catharinensis, benzofuran neolignans, bicyclo[3.2.1]octane neolignans, humulane sesquiterpene, somatic embryos IntroductionOcotea catharinensis (Lauraceae) is a woody plant species found in southern Atlantic forest in Brazil, which produces excellent quality of timber. The extensive logging over the past thirty years associated with difficulties for propagation has led its natural population to be significant decrease. Since O. catharinensis has been included as endangered species, a somatic embryogenic system was developed aiming to a massive propagation. 1,2The Ocotea has been one of the most phytochemically investigated Lauraceous genus and their major secondary compounds were showed to be phenylpropanoidderived including several sub-classes of neolignans. 3Previous phytochemical studies carried out in leaves of O. catharinensis collected at Horto Florestal (Serra da Cantareira), São Paulo State, Brazil, reported the occurrence of benzofuran (1b, 1c, 1d, 2b, 2c, 2d, 2e and 2h) and bicyclo[3.2.1]octane (5a, 5b and 5d) neolignans. 4Representatives of both sub-classes of neolignans have also been previously isolated from barks and woods of a specimen collected in São Paulo State, 5,6 and also from wood and leaves of O. porosa ("imbuia") collected in Rio Grande do Sul State, southern Brazil. [7][8][9] This work describes the isolation and characterization of major secondary compounds from leaves collected at Vale do Itajaí, Santa Catarina State, Brazil and from embryogenic cultures developed from the same plant source. The extracts from leaves afforded seven new neolignans 1e, 2f, 3b, 4b, 5c, 7a, 7b, besides seven previously reported ones 1a, 6,10 Results and DiscussionThe defatted fraction of hexane extracts from O. catharinensis leaves and from O. catharinensis somatic embryos were submitted to flash chromatography followed by prep. TLC and/or circular chromatography (Chromatotron®). This procedure yielded nine new compounds (1e, 2f, 3b, 4a, 4b, 5c, ...

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