Woody Medicinal Plant Research Articles

Woody medicinal plants of the caatinga in the state of Pernambuco (Northeast Brazil)

Floristic and phytosociological studies undertaken in six areas of the state of Pernambuco were selected with the aim of analyzing the Relative Importance of the woody medicinal plant species of Pernambuco's caatinga from an ethnobotanical perspective. For the data analysis, only those identified up to the species level were selected and information on medicinal properties was obtained for each one from the literature. The Relative Importance was calculated for each species. From the 57 woody species, 22 had therapeutic indications; from these, Anacardium occidentale L., Tabebuia impetiginosa (Mart. ex DC) Standley, Schinopsis brasiliensis Engl., and Myracrodruon urundeuva (Engl.) Fr. All. had the greatest values of Relative Importance. The correlation analysis made clear that the Relative Importance of the species is negatively correlated with the Density and Relative Frequency (p<0.05). The most important species, in the ethnobotanical point view, are the most vulnerable, possible due to the systematic exploration they have been suffering. Schinopsis brasiliensis and Myracrodruon urundeuva are listed as endangered species and deserve special attention in the development of techniques of sustainable management, where both economic return and species conservation must be guaranteed. In depth studies that take into consideration each region's characteristics are necessary both from a floristic perspective and considering medicinal aspects, since each area seems to have its own woody medicinal flora, as suggested in the cluster analysis.

Somatic embryogenesis, encapsulation, and plant regeneration of Rotula aquatica lour., a rare rhoeophytic woody medicinal plant

Indirect somatic embryogenesis, encapsulation, and plant regeneration was achieved with the rare rhoeophytic woody medicinal plant Rotula aquatica Lour. (Boraginaceae). Friable callus developed from leaf and internode explants on Murashige and Skoog (MS) medium with 0.45 μM 2,4-dichlorophenoxyacetic, acid (2,4-D) was most effective for the induction of somatic embryos. Subculture of the callus onto half-strength MS medium with the same concentration of 2,4-D resulted in highly embryogenic callus. Suspension culture was superior to solid medium culture for somatic embryogenesis. Embryogenic callus.during subsequent transfer to suspension cultures of half-strength MS medium having 0.23 μM 2,4-D induced the highest number of somatic embryos (a mean of 25.6 embryos per 100 mg callus) and the embryos were grown up to the torpedo stage. Transfer of embryos to half-strength MS basal solid medium allowed development, of 50% of the embryos to the cotyledonary stage. Of the cotyledonary embryos, 90% underwent conversion to plantlets on the same medium. Encapsulated cotyledonary embryos exhibited 100% conversion to plantlets. Ninety-five percent of the plantlets established in field conditions survived, and were morphologically identical to the mother plant.

In vitro regeneration of the medicinal woody plant Phellodendron amurense Rupr. through excised leaves

Shoot organogenesis and plant establishment has been achieved for Phellodendron amurense Rupr. from excised leaf explants. Young leaf explants were collected from in vitro established shoot cultures and used for the induction of direct shoot regeneration, callus and subsequent differentiation into shoots on MS medium. Direct shoot regeneration was achieved by culturing 1 cm2 sections of about 10-day-old leaves on MS medium enriched with 4.4 μM BAP and 1.0 μM NAA after 4 weeks of culture. The leaf explants produced callus from their cut margins within 3 weeks of incubation on medium supplemented with 2.0 μM TDZ and 4.0 μM 2,4-D or 4.0 μM NAA. The maximum number of adventitious shoots was regenerated from the leaf-derived callus within 4 weeks of culture on MS medium containing 1.5 μM BAP and 1.0 μM NAA. The highest rate of shoot multiplication was achieved at the third subculture, and more than 65 shoots were produced per callus clump. For rooting, the in vitro proliferated and elongated shoots were excised into 2–4 cm long microcuttings, which were planted individually on a root-induction MS medium containing 2.0 μM IBA. Within 3 weeks of transfer to the rooting medium, all the cultured microcuttings produced 2–6 roots. The in vitro regenerated plantlets were transferred to Kanuma soil, and the survival rate ex vitro was 90%.

Stem and leaf morphoanatomy of Maytenus ilicifolia

Maytenus ilicifolia is a woody medicinal plant, employed mainly for its antiulcerogenic properties. The stem and leaf morphoanatomy has been studied, aiming to supply knowledge for the pharmacognostic and taxonomic species identification. The vegetative material was fixed, freehand sectioned and stained according to usual microtechniques. The stem organization, in secondary growth, shows periderm beneath the remaining epidermis, conspicuous sclerenchymatic ring in the cortex and cambium forming phloem outside and xylem inside. The leaf is simple, alternate and lanceolate and has sparsely spiny teeth along the margin. Epidermal cells containing calcium oxalate crystals, thick cuticle that forms cuticular flanges, dorsiventral mesophyll and amphicrival bundle in the midrib and petiole are observed.

Mass production of Siberian ginseng plantlets through large-scale tank culture of somatic embryos

Siberian ginseng (Eleutherococcus senticosus) is an endangered medicinal woody plant that is distributed throughout the cold regions of northeast Asia. Its propagation is very difficult. In the present article we describe the mass production of Siberian ginseng plantlets by large-scale tank cultures. High-frequency somatic embryogenesis was achieved through suspension culture of embryogenic cells in Murashige and Skoog (MS) liquid medium lacking 2,4-D. About 12,000 embryos were produced per 500-ml flask after 4 weeks of culture. Cotyledonary somatic embryos were germinated, and these converted into plantlets following a pretreatment of the embryos with gibberellic acid (20 µM) and subsequent transfer to a 10-l plastic tank. Low-strength MS medium (1/5-, 1/3-strength) was more effective than its full-strength counterpart for the production of plantlets. After 40 days, an initial 35-g inoculum of embryos was converted to 567 g fresh mass of plantlets in 1/3-strength MS medium. This result indicates that an efficient protocol for the mass production of Siberian ginseng plantlet can be achieved by tank culture of somatic embryos. The Siberian ginseng plantlets produced can be used as a source of medicinal raw materials.

A kinetic model for growth of callus derived from Eucommia ulmoides aiming at mass production of a factor enhancing collagen synthesis of animal cells

Callus induced from the leaves of Eucommia ulmoides, a medicinal woody plant, was cultivated to produce a factor capable of enhancing collagen synthesis in animal cells (FECS). However, the callus was too rigid to be divided into small pieces by a hydrodynamic force during the cultivation, which led to a slow callus growth characterized by enlargement of the callus size rather than increase in the callus number. Improved growth rate of the callus with smaller sizes and cavity formation in the central region of the callus with its enlargement, implied the occurrence of transfer limitation of nutrient(s) inside the callus. Distributions of the principal nutrients of sugar, nitrogen and dissolved oxygen concentrations across the cultivated callus were simulated by a kinetic model consisting of nutrients diffusion and bioreaction kinetics, suggesting that oxygen transfer in the callus was the limiting factor for the callus growth. A callus growth model considering the effect of the nutrients’ transfer and cell death kinetics in the callus which was caused by the oxygen depletion successfully described the callus enlargement process. Based on these results, a newly developed bioreactor with a fragmentation device enabled the callus to grow with enhanced growth rate by controlling the callus at small sizes during the cultivation.

Efficient plant regeneration from cell suspension protoplasts of the woody medicinal plant Solanum dulcamara L. (bittersweet, woody nightshade)

Large populations of viable protoplasts were released from suspension cultured cells of the woody medicinal plant Solanum dulcamara (bittersweet, woody nightshade) when the cells were harvested 3 to 7 months after culture initiation and 4 to 5 days after transfer to fresh medium. A Bio-Gel p6 purified enzyme mixture enhanced the protoplast plating efficiency 6 fold compared to the unpurified mixture, without affecting protoplast yield. Agarose-solidified medium markedly improved protoplast division and colony formation, and enabled protoplasts to be plated at lower densities than in liquid medium. All protoplast-derived tissues produced shoots on MS based medium with 1.0 mgl-1 zeatin. Shoots rooted readily on medium lacking phytohormones. Cytological examination revealed high chromosome stability of suspension cultured cells, of plants derived from such cells, and of protoplast-derived plants. The implication of these results is discussed in relation to the genetic manipulation of this pharmaceutically important plant.

Electroporation Stimulates Plant Regeneration from Protoplasts of the Woody Medicinal SpeciesSolarium dulcamaraL.

Exposure of cell suspension protoplasts of the woody medicinal plant Solatium dulcamara L. to voltages of 250 to 1250 V cm−1 for three successive pulses, each of 10–50 us duration, stimulated growth of protoplast-derived tissues. Such tissues exhibited increased morphogenesis and required a shorter period in culture to exhibit this effect than tissues from untreated protoplasts. Regenerated shoots also rooted more readily and developed more prolific root systems than shoots from untreated protoplasts. These observations have important implications for plant genetic manipulation and may have application in the recovery and rooting of shoots from tissues of woody species, normally considered recalcitrant in culture.