Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.

Somatic embryogenesis and pant regeneration from callus cultures of Cleome rosea Vahl

This paper describes a protocol for the efficient vegetative propagation of Cleome rosea by somatic embryogenesis. Leaf and stem explants from nursery-grown seedlings of C. rosea were cultivated on Murashige and Skoog (MS) medium supplemented with indole-3-acetic acid (IAA), a -naphthaleneacetic acid (NAA), 4-amino-3,5,6-trichloropicolinic acid (picloram) or 2,4-dichlorophenoxyacetic acid (2,4-D). Nodular calli were produced from both explant types in the presence of 4.5 and 9.0 µM 2,4-D. Embryo development and maturation were achieved when calli from stem explants were transferred to media containing a ten-fold reduction of 2,4-D concentration initially used (0.45 and 0.90 µM). Leaf-derived calli did not form embryos with the same treatments. The highest frequency of embryogenic callus formation (85 percent) and number of embryo per callus (13.45 ± 2.8) were achieved during the first subculture on medium supplemented with 0.90 µM 2,4-D. Embryo conversion into plantlets was achieved following transfer to growth regulator-free MS medium solidified with 2 g.L-1 phytagel. An acclimatization rate of 53 percent was found three months after transfer to ex vitro conditions and the recovered plants presented a normal phenotypic aspect.

O trabalho descreve um protocolo para a propagação in vitro de Cleome rosea por embriogênese somática. Explantes foliares e caulinares, obtidos de plantas germinadas sob condições in vivo, foram cultivados em meio de Murashige and Skoog (MS) suplementado com ácido 3-indolacético (AIA), ácido naftalenoacético (ANA), ácido 4-amino-3,5,6-tricloropicolínico (picloram) ou ácido 2,4-diclorofenoxiacético (2,4-D). Calos de aspecto nodular foram produzidos a partir de ambos os tipos de explante na presença de 4,5 e 9,0 μM de 2,4-D. O desenvolvimento e a maturação de embriões somáticos foram alcançados quando calos obtidos de explantes caulinares foram transferidos para meio de cultura suplementado com uma concentração de 2,4-D dez vezes menor do que aquelas utilizadas na indução do processo de calogênese (0,45 e 0,90 μM). Calos derivados de explantes foliares não produziram embriões ao serem submetidos a estes mesmos tratamentos. Os maiores valores de freqüência de calos embriogênicos (85 por cento) e número médio de embriões por calo (13,45±2,8) foram alcançados durante a primeira subcultura em meio suplementado com 0,90 μM de 2,4-D. O processo de conversão dos embriões somáticos em plantas foi observado após transferência dos embriões para meio MS sem suplementação hormonal solidificado com 2 g.L-1 de fitagel. Três meses após a transferência para condições ex vitro a taxa de aclimatização alcançada foi de 53 por cento e as plantas apresentavam um aspecto fenotípico normal.

Atividade antineoplásica e tripanocida de Hovenia dulcis Thunb. cultivada in vivo e in vitro

Muitas são as substâncias do metabolismo vegetal que têm despertado grande interesse, principalmente no setor de fármacos. No presente estudo, foram avaliadas as atividades antineoplásica e tripanocida de extratos vegetais de Hovenia dulcis (Rhamnaceae) cultivada sob condições in vivo e in vitro. Extratos metanólicos das folhas de material jovem desenvolvido in vivo e in vitro, exibiram altas porcentagens na inibição do crescimento de todas as linhagens de células tumorais testadas, enquanto extratos etanólicos do pseudofruto mostraram seletividade com elevado percentual de inibição do crescimento celular nas linhagens SP2/0 e BW. Quanto à atividade tripanocida, os extratos aquoso do pseudofruto e metanólico das folhas das plantas germinadas in vivo, apresentaram percentual de inibição em 48 h, de 95 por cento e 100 por cento, respectivamente.

Plants produce a wide range of secondary metabolites, many of which are pharmaceutically important. In this paper were evaluated anti-cancer and trypanocidal activities from Hovenia dulcis (Rhamnaceae) in vivo and in vitro propagated plants. Methanolic extracts of young leaves from in vivo and in vitro material were remarkably active for all tumor cells lines tested, while ethanolic extracts of pseudofruit showed high degree of selectivity against to SP2/0 and BW cells in culture. Mortality of 95 and 100 percent (48 h) on Trypanosoma cruzi were observed on the aqueous extract of pseudofruit and methanolic extracts of leaves from seedlings.