... third. ABSTRACT Lopes, SA, Ribeiro, DM, Roberto, PG, França, SC, and Santos, JM 2000. ... sam... more ... third. ABSTRACT Lopes, SA, Ribeiro, DM, Roberto, PG, França, SC, and Santos, JM 2000. ... samples and the positive control. Popula-tion of viable X. fastidiosa cells varied from 4.9 × 104 to 6.6 × 105 CFU/g of to-bacco tissue. Phase ...
Introduction -Although medicinal plants are widely used throughout the world, few studies have be... more Introduction -Although medicinal plants are widely used throughout the world, few studies have been carried out concerning the levels of heavy metal contaminants present. Such metals are highly toxic to living organisms even in low concentrations owing to their cumulative eff ect. The present paper describes the the development of a pre-concentration fl ow injection analysis-fl ame atomic absorption spectrometric system to determine the lead content in medicinal plants at the ppb level.
Jacaranda decurrens (Bignoniaceae) is an endemic species of the Cerrado with validated antitumora... more Jacaranda decurrens (Bignoniaceae) is an endemic species of the Cerrado with validated antitumoral activity. The genetic diversity of six populations of J. decurrens located in the State of São Paulo was determined in this study by using molecular markers for randomly amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP). Following optimization of the amplification reaction, 10 selected primers generated 78 reproducible RAPD fragments that were mostly (69.2%) polymorphic. Two hundred and five reproducible AFLP fragments were generated by using four selected primer combinations; 46.3% of these fragments were polymorphic, indicating a considerable level of genetic diversity. Analysis of molecular variance (AMOVA) using these two groups of markers indicated that variability was strongly structured amongst populations. The unweighted pair group method with arithmatic mean (UPGMA) and Pearson's correlation coefficient (RAPD -0.16, p = 0.2082; AFLP 0.37, p = 0.1006) between genetic matrices and geographic distances suggested that the population structure followed an island model in which a single population of infinite size gave rise to the current populations of J. decurrens, independently of their spatial position. The results of this study indicate that RAPD and AFLP markers were similarly efficient in measuring the genetic variability amongst natural populations of J. decurrens. These data may be useful for developing strategies for the preservation of this medicinal species in the Cerrado.
Croton antisyphiliticus is a medicinal plant widely used in the treatment of microbial infections... more Croton antisyphiliticus is a medicinal plant widely used in the treatment of microbial infections, especially those affecting the genital tract. Crude extract, fractions and pure compound isolated from roots of this species were investigated to validate their antimicrobial activity against Escherichia coli and Staphylococcus aureus. The compound ent-kaur-16-en-18-oic acid was isolated as a major component (0.7% of crude extract), and its MIC value determined against S. aureus (ATCC 6538) was 250 μg/mL. This is the first phytochemical work on the species monitored with antimicrobial assay.
ABSTRACT Extracts of the medicinal plant Palicourea rigida Kunth, popularly known as douradinha, ... more ABSTRACT Extracts of the medicinal plant Palicourea rigida Kunth, popularly known as douradinha, are widely used for treating urinary tract disorders. Unfortunately, nowadays this is one of the species endemic to Brazilian Cerrado that is at greatest risk of extinction. The aim of the this work was to use AFLP molecular markers to determine the genetic structure and diversity of eight natural populations of P. rigida and to associate their genetic characteristics with loganin production in order to obtain provide relevant information to promote programs for the conservation of this valuable medicinal plant. A total of 120 polymorphic bands were scored and higher proportion of genetic diversity was found in inter-populations (64%) rather than in intra-populations (36%). Fst value was found to be significantly greater than zero (0.3601), demonstrating the complex genetic structure of P. rigida populations. Accessions collected from Cristalina, GO, showed higher percentage of polymorphic loci (65.5%) and the highest genetic diversity. Analysis of Molecular variance (AMOVA) demonstrated 63.9% of intra-population genetic variation. The lowest genetic variability was detected among accessions from the population found in Sacramento, MG. No spatial standard was observed for P. rigida population, suggesting a partially isolated island model. It was observed a minor but significant positive correlation (r = 0.22) between chemical and genetic matrices. The association between chemical and genetic data indicated that environmental factors promoted the loganin production in populations growing in Luziânia, GO, and therefore accessions from those populations should be considered as prime material for initiating the conservation process of P. rigida.
The HIV-tuberculosis co-infection has caused an impact on tuberculosis epidemiology all over the ... more The HIV-tuberculosis co-infection has caused an impact on tuberculosis epidemiology all over the world and the efficacies of the therapeutic schemes traditionally prescribed in the treatment of tuberculosis, such as isoniazid, rifampicin and pyrazinamide, have decreased due to the appearance of multidrug-resistant M. tuberculosis strains (MDR). This work is part of research on natural antimicrobial agents from plant extracts through bioassay-guided fractionation, by in vitro determination of the minimum inhibitory concentration (MIC) using the microdilution method with Alamar blue oxidation-reduction dye. Crude CHCl3Physalis angulata extracts and physalin-containing fractions displayed antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium malmoense and Mycobacterium intracellulare.
A protocol for in vitro micropropagation of Eclipta alba (L.) Hassk from nodal segment explants h... more A protocol for in vitro micropropagation of Eclipta alba (L.) Hassk from nodal segment explants has been established. The maximum number of shoots was obtained after 60 days of culture in Murashige & Skoog (MS) medium supplemented with 4.4 μM benzyladenine. Multiple rooting was achieved using MS medium with 2.4 μM 2-isopentyladenine. Wedelolactone was present in shoots cultured in media containing cytokinins.
Evidence-Based Complementary and Alternative Medicine, 2013
The antihyperglycemic effects of several plant extracts and herbal formulations which are used as... more The antihyperglycemic effects of several plant extracts and herbal formulations which are used as antidiabetic formulations have been described and confirmed to date. The main objective of this work was to evaluate the hypoglycemic activity of the aqueous extract of Anacardium humile. Although the treatment of diabetic animals with A. humile did not alter body weight significantly, a reduction of the other evaluated parameters was observed. Animals treated with A. humile did not show variation of insulin levels, possibly triggered by a mechanism of blood glucose reduction. Levels of ALT (alanine aminotransferase) decreased in treated animals, suggesting a protective effect on liver. Levels of cholesterol were also reduced, indicating the efficacy of the extract in reestablishing the balance of nutrients. Moreover, a kidney protection may have been achieved due to the partial reestablishment of blood glucose homeostasis, while no nephrotoxicity could be detected for A. humile. The obtained results demonstrate the effectiveness of A. humile extracts in the treatment of alloxan-induced diabetic rats. Therefore, A. humile aqueous extract, popularly known and used by diabetic patients, induced an improvement in the biochemical parameters evaluated during and following treatment of diabetic rats. Thus, a better characterization of the medicinal potential of this plant will be able to provide a better understanding of its mechanisms of action in these pathological processes.
Bark extracts of Stryphnodendron adstringens (Mart.) Coville a Leguminosae species, well known in... more Bark extracts of Stryphnodendron adstringens (Mart.) Coville a Leguminosae species, well known in Brazil as barbatimão, are popularly used as healing agent. The objective of this work was to determine the genetic diversity of S. adstringens populations and to correlate genetic distances to the production of tannins. S. adstringens accessions from populations found in Cerrado regions in the states of Goiás, Minas Gerais and São Paulo were analyzed using the AFLP (Amplified Fragment Length Polymorphism) technique. A total of 236 polymorphic bands were scored and higher proportion of genetic diversity was found inter populations (70.9%), rather than intra populations (29.1%). F ST value was found to be significantly greater than zero (0.2906), demonstrating the complex genetic structure of S. adstringens populations. Accessions collected in Cristalina, GO, showed higher percentage of polymorphic loci (87.3%) and the highest genetic diversity. The lowest genetic variability was detected among accessions from the population growing in Caldas Novas, GO. The genetic distance among populations was estimated using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), which grouped populations into 3 clusters. Moreover, chemotypes with tannin concentration above 40% showed higher genetic similarity. AFLP analysis proved to be an efficient gene mapping technique to determine the genetic diversity among remaining populations of S. adstringens. Obtained results may be employed to implement further strategies for the conservation of this medicinal plant.
ABSTRACT The quinone-methide triterpenoids (QMTs) are chemotaxonomic markers of the family Celast... more ABSTRACT The quinone-methide triterpenoids (QMTs) are chemotaxonomic markers of the family Celastraceae and many compounds of this class possess important anticancer and anti-inflammatory activities. However, the levels of QMTs in the roots of Celastraceous species are typically very low (ca. 0.0003 %) and commercial production by extraction from such tissues would not be commercially viable. With the aim of determining if cells cultured in vitro might provide alternative sources of these bioactive triterpenoids, we have quantified and compared the concentrations of QMTs accumulated by the roots of plants of Maytenus ilicifolia Mart. ex Reissek (Celastraceae) aged 0.5–10 years, and in callus and suspension cultures derived from a cell line that had been subcultured over a period of 10 years. Comparing plants cultivated in natura, the highest levels of QMTs were detected in the root bark of 5-year old specimens. However, cell suspensions derived from the long-term cell line retained their capacity to synthesize and accumulate QMTs, and presented levels of maytenin, 22β-hydroxymaytenin, celastrol and pristimerin that were, respectively, 1.96-, 2.48-, 8.85- and 3.29-times higher than those in the roots of 5-year old plants. The results presented herein open up new possibilities for the large-scale production of QMTs and for the development of novel pharmaceuticals.
Phospholipases A2 (PLA2) are multifunctional proteins which exhibit varied biological activities ... more Phospholipases A2 (PLA2) are multifunctional proteins which exhibit varied biological activities correlated to the structural diversities of the sub-classes. The crude aqueous extract from subterranean system of Mandevilla velutina, a plant found in Brazilian savanna, was assayed for its ability to inhibit biological activities of several snake venoms and isolated PLA2s. The extract induced total inhibition of the phospholipase activity of Crotalus durissus terrificus venom and only partial inhibition of Bothrops venoms. When assayed against purified toxins, the highest efficacy was detected against CB and crotoxin, while almost ineffective against PLA2s from the genus Bothrops. Although M. velutina crude extract significantly inhibited the myotoxic activity of C. d. terrificus venom and CB, it produced only partial inhibition of either Bothrops jararacussu venom or its main myotoxins BthTX-I (basic Lys49), BthTX-II (basic Asp49) and BthA-I-PLA2 (acidic Asp49). The extract exhibited also full inhibition of hemorrhage caused by Bothrops alternatus, Bothrops moojeni and Bothrops pirajai snake venoms, but partial inhibition (90%) of that induced by B. jararacussu venom. The extract was ineffective to inhibit the fibrinogenolytic activity of B. moojeni, B. alternatus and B. pirajai crude venoms, while their caseinolytic activity was only partially inhibited. No inhibition of the anticoagulant activity, although partial reduction of the edema-inducing activity of C. d. terrificus and B. alternatus crude venoms, CB, PrTX-I, BthTX-I and crotoxin was observed. Besides extending survival of mice injected with lethal doses of C. d. terrificus and B. jararacussu venoms, M. velutina extract decreased to 50% the lethality of mice. Extracts of 18 month old micropropagated plants were able to partially neutralize the effect of the crude venoms and toxins.
An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu ven... more An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu venomous gland, according to sequence similarities of their domains, is described. The program was written in C and Perl languages. This algorithm compares a domain with each ORF protein sequence in the database. Each nucleotide FASTA sequence generates six ORFs. As a result, the user has a list containing all sequences found in a specific domain and a display of the sequence, domain and number of hits. The algorithm lists only the sequences that present a minimum similarity of 30 hits and the best alignment. This limit was considered appropriate. The algorithm is available in the Internet (www.compbionet.org.br/cgi-domains/homesnake) and it can quickly and accurately organizes large database into classes.
Micropropagated shoots of Maytenus ilicifolia Mart. were obtained from axillary buds cultured in ... more Micropropagated shoots of Maytenus ilicifolia Mart. were obtained from axillary buds cultured in Murashige & Skoog medium supplemented with 13.3 μM 6-benzyladenine (BA). Addition of 1.1 μM 1-indole-3-acetic acid (IAA) to the medium increased shoot elongation. The number of shoots formed was influenced by BA concentration, degree of juvenility of the explant, and by bud explant position on the stem. Cultures of buds taken from stem parts located close to the shoot tip yielded more callus than shoots, whereas axillary buds at distant positions from the apical bud yielded more shoots.
Maytenus aquifolium (Celastraceae) and Salacia campestris (Hippocrateaceae) species accumulate fr... more Maytenus aquifolium (Celastraceae) and Salacia campestris (Hippocrateaceae) species accumulate friedelane and quinonemethide triterpenoids in their leaves and root bark, respectively. Enzymatic extracts obtained from leaves displayed cyclase activity with conversion of the substrate oxidosqualene to the triterpenes, 3β-friedelanol and friedelin. In addition, administration of (±)5-3H mevalonolactone in leaves of M. aquifolium seedlings produced radio labelled friedelin in the leaves, twigs and stems, while the root bark accumulated labelled maytenin and pristimerin. These experiments indicated that the triterpenes once biosynthesized in the leaves are translocated to the root bark and further transformed to the antitumoral quinonemethide triterpenoids.
The establishment of a micropropagation protocol for Pothomorphe umbellata was carried out using ... more The establishment of a micropropagation protocol for Pothomorphe umbellata was carried out using leaf segments cultured on 1/4 strength Murashige and Skoog medium supplemented with 0.5 mg l-1 6-benzyladenine, 0.1 mg l-1 gibberelic acid added with 10 g l-1 sucrose. Rooting was achieved using MS medium devoid of growth regulators. An anatomical study confirmed shoot regeneration via direct organogenesis.
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically i... more Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis-a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.
In order to produce explants of Mandevilla illustris (Vell) Woodson for the “Cerrado in vitro”, t... more In order to produce explants of Mandevilla illustris (Vell) Woodson for the “Cerrado in vitro”, the Germplasm Bank of UNAERP, we carried out a micropropagation protocol using MS or MS/3 medium supplemented with different concentrations of 6-benzyladeninepurine (BA), Zeatin or 2-isopentenyladenine for nodal segment growth, and α-naphthaleneacetic acid, indole-3-butyric acid (IBA) or 1,4 dithiothreitol for rooting. For nodal segments, all the cytokinins tested yielded similar results. However, 2.22 µM BA is more economical to use. MS/3 medium supplemented with 0.49 µM IBA was the most appropriate medium for rooting, resulting in 29% rooted explants. The crude aqueous extract from the subterranean system (SS) of M. illustris was assayed for its inhibitory action on the enzymatic activity of Crotalus durissus terrificus snake venom, isolated basic phospholipase A2 (CB) and crotoxin. It totally inhibited the phospholipase activity of crude Cdt venom and CB toxin and inhibited the phospholipase activity of crotoxin by 49%. The toxic action of both the crude venom and crotoxin was partially inhibited—there was a prolonged survival time and a 40.0% decrease in lethality.
... third. ABSTRACT Lopes, SA, Ribeiro, DM, Roberto, PG, França, SC, and Santos, JM 2000. ... sam... more ... third. ABSTRACT Lopes, SA, Ribeiro, DM, Roberto, PG, França, SC, and Santos, JM 2000. ... samples and the positive control. Popula-tion of viable X. fastidiosa cells varied from 4.9 × 104 to 6.6 × 105 CFU/g of to-bacco tissue. Phase ...
Introduction -Although medicinal plants are widely used throughout the world, few studies have be... more Introduction -Although medicinal plants are widely used throughout the world, few studies have been carried out concerning the levels of heavy metal contaminants present. Such metals are highly toxic to living organisms even in low concentrations owing to their cumulative eff ect. The present paper describes the the development of a pre-concentration fl ow injection analysis-fl ame atomic absorption spectrometric system to determine the lead content in medicinal plants at the ppb level.
Jacaranda decurrens (Bignoniaceae) is an endemic species of the Cerrado with validated antitumora... more Jacaranda decurrens (Bignoniaceae) is an endemic species of the Cerrado with validated antitumoral activity. The genetic diversity of six populations of J. decurrens located in the State of São Paulo was determined in this study by using molecular markers for randomly amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP). Following optimization of the amplification reaction, 10 selected primers generated 78 reproducible RAPD fragments that were mostly (69.2%) polymorphic. Two hundred and five reproducible AFLP fragments were generated by using four selected primer combinations; 46.3% of these fragments were polymorphic, indicating a considerable level of genetic diversity. Analysis of molecular variance (AMOVA) using these two groups of markers indicated that variability was strongly structured amongst populations. The unweighted pair group method with arithmatic mean (UPGMA) and Pearson's correlation coefficient (RAPD -0.16, p = 0.2082; AFLP 0.37, p = 0.1006) between genetic matrices and geographic distances suggested that the population structure followed an island model in which a single population of infinite size gave rise to the current populations of J. decurrens, independently of their spatial position. The results of this study indicate that RAPD and AFLP markers were similarly efficient in measuring the genetic variability amongst natural populations of J. decurrens. These data may be useful for developing strategies for the preservation of this medicinal species in the Cerrado.
Croton antisyphiliticus is a medicinal plant widely used in the treatment of microbial infections... more Croton antisyphiliticus is a medicinal plant widely used in the treatment of microbial infections, especially those affecting the genital tract. Crude extract, fractions and pure compound isolated from roots of this species were investigated to validate their antimicrobial activity against Escherichia coli and Staphylococcus aureus. The compound ent-kaur-16-en-18-oic acid was isolated as a major component (0.7% of crude extract), and its MIC value determined against S. aureus (ATCC 6538) was 250 μg/mL. This is the first phytochemical work on the species monitored with antimicrobial assay.
ABSTRACT Extracts of the medicinal plant Palicourea rigida Kunth, popularly known as douradinha, ... more ABSTRACT Extracts of the medicinal plant Palicourea rigida Kunth, popularly known as douradinha, are widely used for treating urinary tract disorders. Unfortunately, nowadays this is one of the species endemic to Brazilian Cerrado that is at greatest risk of extinction. The aim of the this work was to use AFLP molecular markers to determine the genetic structure and diversity of eight natural populations of P. rigida and to associate their genetic characteristics with loganin production in order to obtain provide relevant information to promote programs for the conservation of this valuable medicinal plant. A total of 120 polymorphic bands were scored and higher proportion of genetic diversity was found in inter-populations (64%) rather than in intra-populations (36%). Fst value was found to be significantly greater than zero (0.3601), demonstrating the complex genetic structure of P. rigida populations. Accessions collected from Cristalina, GO, showed higher percentage of polymorphic loci (65.5%) and the highest genetic diversity. Analysis of Molecular variance (AMOVA) demonstrated 63.9% of intra-population genetic variation. The lowest genetic variability was detected among accessions from the population found in Sacramento, MG. No spatial standard was observed for P. rigida population, suggesting a partially isolated island model. It was observed a minor but significant positive correlation (r = 0.22) between chemical and genetic matrices. The association between chemical and genetic data indicated that environmental factors promoted the loganin production in populations growing in Luziânia, GO, and therefore accessions from those populations should be considered as prime material for initiating the conservation process of P. rigida.
The HIV-tuberculosis co-infection has caused an impact on tuberculosis epidemiology all over the ... more The HIV-tuberculosis co-infection has caused an impact on tuberculosis epidemiology all over the world and the efficacies of the therapeutic schemes traditionally prescribed in the treatment of tuberculosis, such as isoniazid, rifampicin and pyrazinamide, have decreased due to the appearance of multidrug-resistant M. tuberculosis strains (MDR). This work is part of research on natural antimicrobial agents from plant extracts through bioassay-guided fractionation, by in vitro determination of the minimum inhibitory concentration (MIC) using the microdilution method with Alamar blue oxidation-reduction dye. Crude CHCl3Physalis angulata extracts and physalin-containing fractions displayed antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium malmoense and Mycobacterium intracellulare.
A protocol for in vitro micropropagation of Eclipta alba (L.) Hassk from nodal segment explants h... more A protocol for in vitro micropropagation of Eclipta alba (L.) Hassk from nodal segment explants has been established. The maximum number of shoots was obtained after 60 days of culture in Murashige & Skoog (MS) medium supplemented with 4.4 μM benzyladenine. Multiple rooting was achieved using MS medium with 2.4 μM 2-isopentyladenine. Wedelolactone was present in shoots cultured in media containing cytokinins.
Evidence-Based Complementary and Alternative Medicine, 2013
The antihyperglycemic effects of several plant extracts and herbal formulations which are used as... more The antihyperglycemic effects of several plant extracts and herbal formulations which are used as antidiabetic formulations have been described and confirmed to date. The main objective of this work was to evaluate the hypoglycemic activity of the aqueous extract of Anacardium humile. Although the treatment of diabetic animals with A. humile did not alter body weight significantly, a reduction of the other evaluated parameters was observed. Animals treated with A. humile did not show variation of insulin levels, possibly triggered by a mechanism of blood glucose reduction. Levels of ALT (alanine aminotransferase) decreased in treated animals, suggesting a protective effect on liver. Levels of cholesterol were also reduced, indicating the efficacy of the extract in reestablishing the balance of nutrients. Moreover, a kidney protection may have been achieved due to the partial reestablishment of blood glucose homeostasis, while no nephrotoxicity could be detected for A. humile. The obtained results demonstrate the effectiveness of A. humile extracts in the treatment of alloxan-induced diabetic rats. Therefore, A. humile aqueous extract, popularly known and used by diabetic patients, induced an improvement in the biochemical parameters evaluated during and following treatment of diabetic rats. Thus, a better characterization of the medicinal potential of this plant will be able to provide a better understanding of its mechanisms of action in these pathological processes.
Bark extracts of Stryphnodendron adstringens (Mart.) Coville a Leguminosae species, well known in... more Bark extracts of Stryphnodendron adstringens (Mart.) Coville a Leguminosae species, well known in Brazil as barbatimão, are popularly used as healing agent. The objective of this work was to determine the genetic diversity of S. adstringens populations and to correlate genetic distances to the production of tannins. S. adstringens accessions from populations found in Cerrado regions in the states of Goiás, Minas Gerais and São Paulo were analyzed using the AFLP (Amplified Fragment Length Polymorphism) technique. A total of 236 polymorphic bands were scored and higher proportion of genetic diversity was found inter populations (70.9%), rather than intra populations (29.1%). F ST value was found to be significantly greater than zero (0.2906), demonstrating the complex genetic structure of S. adstringens populations. Accessions collected in Cristalina, GO, showed higher percentage of polymorphic loci (87.3%) and the highest genetic diversity. The lowest genetic variability was detected among accessions from the population growing in Caldas Novas, GO. The genetic distance among populations was estimated using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), which grouped populations into 3 clusters. Moreover, chemotypes with tannin concentration above 40% showed higher genetic similarity. AFLP analysis proved to be an efficient gene mapping technique to determine the genetic diversity among remaining populations of S. adstringens. Obtained results may be employed to implement further strategies for the conservation of this medicinal plant.
ABSTRACT The quinone-methide triterpenoids (QMTs) are chemotaxonomic markers of the family Celast... more ABSTRACT The quinone-methide triterpenoids (QMTs) are chemotaxonomic markers of the family Celastraceae and many compounds of this class possess important anticancer and anti-inflammatory activities. However, the levels of QMTs in the roots of Celastraceous species are typically very low (ca. 0.0003 %) and commercial production by extraction from such tissues would not be commercially viable. With the aim of determining if cells cultured in vitro might provide alternative sources of these bioactive triterpenoids, we have quantified and compared the concentrations of QMTs accumulated by the roots of plants of Maytenus ilicifolia Mart. ex Reissek (Celastraceae) aged 0.5–10 years, and in callus and suspension cultures derived from a cell line that had been subcultured over a period of 10 years. Comparing plants cultivated in natura, the highest levels of QMTs were detected in the root bark of 5-year old specimens. However, cell suspensions derived from the long-term cell line retained their capacity to synthesize and accumulate QMTs, and presented levels of maytenin, 22β-hydroxymaytenin, celastrol and pristimerin that were, respectively, 1.96-, 2.48-, 8.85- and 3.29-times higher than those in the roots of 5-year old plants. The results presented herein open up new possibilities for the large-scale production of QMTs and for the development of novel pharmaceuticals.
Phospholipases A2 (PLA2) are multifunctional proteins which exhibit varied biological activities ... more Phospholipases A2 (PLA2) are multifunctional proteins which exhibit varied biological activities correlated to the structural diversities of the sub-classes. The crude aqueous extract from subterranean system of Mandevilla velutina, a plant found in Brazilian savanna, was assayed for its ability to inhibit biological activities of several snake venoms and isolated PLA2s. The extract induced total inhibition of the phospholipase activity of Crotalus durissus terrificus venom and only partial inhibition of Bothrops venoms. When assayed against purified toxins, the highest efficacy was detected against CB and crotoxin, while almost ineffective against PLA2s from the genus Bothrops. Although M. velutina crude extract significantly inhibited the myotoxic activity of C. d. terrificus venom and CB, it produced only partial inhibition of either Bothrops jararacussu venom or its main myotoxins BthTX-I (basic Lys49), BthTX-II (basic Asp49) and BthA-I-PLA2 (acidic Asp49). The extract exhibited also full inhibition of hemorrhage caused by Bothrops alternatus, Bothrops moojeni and Bothrops pirajai snake venoms, but partial inhibition (90%) of that induced by B. jararacussu venom. The extract was ineffective to inhibit the fibrinogenolytic activity of B. moojeni, B. alternatus and B. pirajai crude venoms, while their caseinolytic activity was only partially inhibited. No inhibition of the anticoagulant activity, although partial reduction of the edema-inducing activity of C. d. terrificus and B. alternatus crude venoms, CB, PrTX-I, BthTX-I and crotoxin was observed. Besides extending survival of mice injected with lethal doses of C. d. terrificus and B. jararacussu venoms, M. velutina extract decreased to 50% the lethality of mice. Extracts of 18 month old micropropagated plants were able to partially neutralize the effect of the crude venoms and toxins.
An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu ven... more An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu venomous gland, according to sequence similarities of their domains, is described. The program was written in C and Perl languages. This algorithm compares a domain with each ORF protein sequence in the database. Each nucleotide FASTA sequence generates six ORFs. As a result, the user has a list containing all sequences found in a specific domain and a display of the sequence, domain and number of hits. The algorithm lists only the sequences that present a minimum similarity of 30 hits and the best alignment. This limit was considered appropriate. The algorithm is available in the Internet (www.compbionet.org.br/cgi-domains/homesnake) and it can quickly and accurately organizes large database into classes.
Micropropagated shoots of Maytenus ilicifolia Mart. were obtained from axillary buds cultured in ... more Micropropagated shoots of Maytenus ilicifolia Mart. were obtained from axillary buds cultured in Murashige & Skoog medium supplemented with 13.3 μM 6-benzyladenine (BA). Addition of 1.1 μM 1-indole-3-acetic acid (IAA) to the medium increased shoot elongation. The number of shoots formed was influenced by BA concentration, degree of juvenility of the explant, and by bud explant position on the stem. Cultures of buds taken from stem parts located close to the shoot tip yielded more callus than shoots, whereas axillary buds at distant positions from the apical bud yielded more shoots.
Maytenus aquifolium (Celastraceae) and Salacia campestris (Hippocrateaceae) species accumulate fr... more Maytenus aquifolium (Celastraceae) and Salacia campestris (Hippocrateaceae) species accumulate friedelane and quinonemethide triterpenoids in their leaves and root bark, respectively. Enzymatic extracts obtained from leaves displayed cyclase activity with conversion of the substrate oxidosqualene to the triterpenes, 3β-friedelanol and friedelin. In addition, administration of (±)5-3H mevalonolactone in leaves of M. aquifolium seedlings produced radio labelled friedelin in the leaves, twigs and stems, while the root bark accumulated labelled maytenin and pristimerin. These experiments indicated that the triterpenes once biosynthesized in the leaves are translocated to the root bark and further transformed to the antitumoral quinonemethide triterpenoids.
The establishment of a micropropagation protocol for Pothomorphe umbellata was carried out using ... more The establishment of a micropropagation protocol for Pothomorphe umbellata was carried out using leaf segments cultured on 1/4 strength Murashige and Skoog medium supplemented with 0.5 mg l-1 6-benzyladenine, 0.1 mg l-1 gibberelic acid added with 10 g l-1 sucrose. Rooting was achieved using MS medium devoid of growth regulators. An anatomical study confirmed shoot regeneration via direct organogenesis.
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically i... more Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis-a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.
In order to produce explants of Mandevilla illustris (Vell) Woodson for the “Cerrado in vitro”, t... more In order to produce explants of Mandevilla illustris (Vell) Woodson for the “Cerrado in vitro”, the Germplasm Bank of UNAERP, we carried out a micropropagation protocol using MS or MS/3 medium supplemented with different concentrations of 6-benzyladeninepurine (BA), Zeatin or 2-isopentenyladenine for nodal segment growth, and α-naphthaleneacetic acid, indole-3-butyric acid (IBA) or 1,4 dithiothreitol for rooting. For nodal segments, all the cytokinins tested yielded similar results. However, 2.22 µM BA is more economical to use. MS/3 medium supplemented with 0.49 µM IBA was the most appropriate medium for rooting, resulting in 29% rooted explants. The crude aqueous extract from the subterranean system (SS) of M. illustris was assayed for its inhibitory action on the enzymatic activity of Crotalus durissus terrificus snake venom, isolated basic phospholipase A2 (CB) and crotoxin. It totally inhibited the phospholipase activity of crude Cdt venom and CB toxin and inhibited the phospholipase activity of crotoxin by 49%. The toxic action of both the crude venom and crotoxin was partially inhibited—there was a prolonged survival time and a 40.0% decrease in lethality.
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Papers by Suzelei Franca