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1.
Biol. Res ; 52: 3, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011433

RESUMO

BACKGROUND: Gymnema sylvestre is a medicinal woody perennial vine known for its sweetening properties and antidiabetic therapeutic uses in the modern and traditional medicines. Its over-exploitation for the therapeutic uses and to meet the demand of pharmaceutical industry in raw materials supply for the production of anti-diabetic drugs has led to considerable decline in its natural population. RESULTS: An efficient system of shoot bud sprouting from nodal segment explants and indirect plant regeneration from apical meristem-induced callus cultures of G. sylvestre have been developed on Murashige and Skoog (MS) medium amended with concentrations of cytokinins. Of the three growth regulators tested, N6-benzylaminopurine (BAP) was the most efficient and 2.0 mg L-1 gave the best shoot formation efficiency. This was followed by thidiazuron (TDZ) and kinetin (Kin) but, most of the TDZ-induced micro shoots showed stunted growth. Multiple shoot formation was observed on medium amended with BAP or TDZ at higher concentrations. The produced micro shoots were rooted on half strength MS medium amended with auxins and rooted plantlets acclimatized with 87% survival of the regenerates. CONCLUSIONS: The developed regeneration system can be exploited for genetic transformation studies, particularly when aimed at producing its high yielding cell lines for the anti-diabetic phytochemicals. It also offers opportunities for exploring the expression of totipotency in the anti-diabetic perennial vine.


Assuntos
Reguladores de Crescimento de Plantas/farmacologia , Regeneração/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Gymnema sylvestre/crescimento & desenvolvimento , Morfogênese/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Purinas/farmacologia , Tiadiazóis/farmacologia , Compostos de Benzil/farmacologia , Brotos de Planta/efeitos dos fármacos , Gymnema sylvestre/efeitos dos fármacos , Cinetina/farmacologia
2.
Electron. j. biotechnol ; 27: 80-83, May. 2017. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1010415

RESUMO

Background: A protocol for the micropropagation of the grape (Vitis vinifera L.) cultivar 'Monastrell' was developed. Initial plant material was obtained from the sanitary selection of grapevine plants performed by real-time RT-PCR to confirm the absence of Grapevine fanleaf virus, Arabis mosaic virus, Grapevine leafroll-associated virus 1, Grapevine leafroll-associated virus 3, and Grapevine fleck virus. Results: The effects of the salt composition (comparing Lloyd and McCown woody plant medium and Murashige and Skoog medium 1/2 macronutrients) and the growth regulator benzylaminopurine (BAP), at 0 and 8.9 µM, on plant propagation were evaluated using nodes as explants. The most efficient procedure consisted of bud induction in the medium with Lloyd and McCown woody plant salts and 8.9 µM BAP for 30 d along with elongation in cytokinin-free medium for 60 d, which gave 22 nodes/explant (174 plants/initial plant). A second cycle of propagation in a medium without BAP for another 60 d could give approximately 10,000 nodes, which can be obtained after an additional 2 months of culture. All plants acclimatized after the second cycle of multiplication were successfully transferred to soil. Conclusion: We developed an optimal protocol for V. vinifera cv. 'Monastrell' micropropagation, the first described for this cultivar.


Assuntos
Vitis/crescimento & desenvolvimento , Purinas/metabolismo , Compostos de Benzil/metabolismo , Técnicas In Vitro , Cloreto de Sódio/metabolismo , Vitis/virologia , Reação em Cadeia da Polimerase em Tempo Real , Aclimatação
3.
Biol. Res ; 50: 20, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-950891

RESUMO

BACKGROUND: Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. RESULTS: In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3-6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. CONCLUSIONS: For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.


Assuntos
Purinas/farmacologia , Regeneração/efeitos dos fármacos , Compostos de Benzil/farmacologia , Brotos de Planta/embriologia , Meristema/crescimento & desenvolvimento , Fragaria/embriologia , Chile , Brotos de Planta/efeitos dos fármacos , Meristema/efeitos dos fármacos , Meios de Cultura , Fragaria/efeitos dos fármacos
4.
Bol. latinoam. Caribe plantas med. aromát ; 13(6): 517-526, nov.2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-795822

RESUMO

The study aimed to evaluate the bactericidal activity of oil essential and dillapiole from P. aduncum against standard and multidrug-resistant strains of Staphylococcus spp. The oil showed antimicrobial action against these strains, but better results were obtained for the standards strains of S. epidermidis and S. aureus, with MIC of 250 and 500 ug/mL, respectively. Dillapiolle was less effective than the oil against the same standard and multi-drug resistant strains (MIC =1000 ug/mL). However, when dillapiolle was tested in combination with myristicin, another component of the oil, it increased its bactericidal activity and showed a synergistic action...


El objetivo del estudio fue evaluar la actividad bactericida de los aceites esenciales y dillapiole de P. aduncum contra cepas estándar y multirresistentes de Staphylococcus spp. El aceite mostró acción antimicrobiana frente a estas cepas, pero se obtuvo mejores resultados para las cepas de S. epidermidis y S. aureus, con MIC de 250 y 500 ug/ml, respectivamente. Dillapiolle fue menos eficaz que el aceite contra cepas estándar y multirresistentes (MIC = 1000 ug/ml). Sin embargo, cuando dillapiolle fue probado en combinación con la miristicina, otro componente del aceite, que aumentó su actividad bactericida y mostró una acción sinérgica...


Assuntos
Humanos , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Piper/química , Compostos Alílicos/farmacologia , Compostos de Benzil/farmacologia , Farmacorresistência Fúngica Múltipla , Monoterpenos/farmacologia , Staphylococcus
5.
Braz. j. microbiol ; 45(3): 929-932, July-Sept. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-727022

RESUMO

The β-ketoester benzyl acetoacetate was enantioselectively reduced to benzyl (S)-3-hydroxybutanoate by seven microorganism species. The best result using free cells was obtained with the yeast Hansenula sp., which furnished 97% ee and 85% of conversion within 24 h. After immobilization in calcium alginate spheres, K.marxianus showed to be more stable after 2 cycles of reaction.


Assuntos
Acetoacetatos/metabolismo , Compostos de Benzil/metabolismo , Kluyveromyces/metabolismo , Pichia/metabolismo , Células Imobilizadas/metabolismo , Oxirredução , Fatores de Tempo
6.
Biol. Res ; 45(2): 131-136, 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-648571

RESUMO

An efficient protocol for organogenesis through leaves has been established for Launaea sarmentosa (Willd.) Sch. Bip. ex Kuntze, a highly valuable medicinal plant. The leaf explants produced microshoots on MS basal medium when fortified with cytokinins and auxins. A combination of 6-benzylaminopurine (BAP) at 0.5mg/l and naphthaleneacetic acid (NAA) at 0.2mg/l resulted in the induction of high frequency microshoots in 30 days. The microshoots were successfully subcultured for shoot elongation and eventually for rooting on MS medium supplemented with indole-3-butyric acid (IBA) at 0.5mg/l. The regenerated plantlets were hardened under greenhouse conditions and transferred to garden, resulting in a 90% survival rate.


Assuntos
Asteraceae/crescimento & desenvolvimento , Organogênese Vegetal/fisiologia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Regeneração/fisiologia , Asteraceae/efeitos dos fármacos , Compostos de Benzil/farmacologia , Ácidos Naftalenoacéticos , Organogênese Vegetal/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Purinas/farmacologia , Regeneração/efeitos dos fármacos
8.
Biocell ; 33(3): 141-148, Dec. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-595018

RESUMO

Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatment s with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.


Assuntos
Ciclopentanos/farmacologia , Compostos Organofosforados/farmacologia , Compostos de Benzil/farmacologia , Etilenos/farmacologia , Etilenos/metabolismo , Purinas/farmacologia , Componentes Aéreos da Planta/crescimento & desenvolvimento , Componentes Aéreos da Planta , Pinus/crescimento & desenvolvimento , Pinus , Reguladores de Crescimento de Plantas/farmacologia
9.
West Indian med. j ; 58(5): 407-409, Nov. 2009.
Artigo em Inglês | LILACS | ID: lil-672511

RESUMO

Studies conducted on the secondary metabolite (natural product), dibenzyl trisulphide (DTS), which was isolated from the sub-tropical shrub Petiveria alliacea (guinea hen weed, anamu) [Phytolaccaceae] have shown tremendous pharmaceutical promise as a drug prototype. This is now reflected in the development of the broad spectrum anti-cancer molecule, fluorapacin (bis(4-fluorobenzyl) trisulphide) which has an excellent safety profile. The mode of action elucidated for DTS is the mitogen activated protein extracellular regulated kinases 1 and 2 (MAPKinases ERK 1 and ERK 2). The MAPKinase signal transduction biochemical pathways are important in the regulation of a wide range of cellular processes which are important in disease establishment. These processes include: cancer cell proliferation, nerve repair, memory enhancement, autoimmune diseases, which are linked to thymic cell involution and bone marrow functions, cerebrovascular and cardiovascular diseases. In addition to the MAPkinase signal transduction mode of action, DTS also prevents the denaturation of serum albumin which is a feature of nonsteroidal anti-inflammatory drugs, thus supporting the molecule's possible role in the treatment of inflammatory ageing diseases.


Los estudios realizados sobre el metabolito secundario (producto natural), trisulfuro de dibencilo (TSD), que fue aislado del arbusto subtropical Petiveria alliacea (hierba de guinea, anamú) [Phytolaccaceae] muestran que se trata de una tremenda promesa farmacéutica como prototipo de droga. Esto se refleja actualmente en el desarrollo de la molécula anticancerígena de amplio espectro, la fluorapacina (bis (4-fluorobencilo) trisulfuro) que posee un excelente perfil de seguridad. El modo de acción para el TSD se explica partiendo de las proteínas quinasas 1 y 2 activadas por mitógenos y reguladas por señales extracelulares (Quinasas MAP ERK 1 y ERK 2). Las vías bioquímicas de transducción de la señal de la quinasa MAP, son importantes en la regulación de una amplia variedad de procesos celulares, importantes a la hora de determinar una enfermedad. Dichos procesos comprenden: la proliferación de la célula cancerosa, la reparación de nervios, el mejoramiento de la memoria, y las enfermedades autoinmunes, vinculadas con la involución tímica y las funciones de la médula, las enfermedades cerebrovasculares y cardiovasculares. Además del modo de acción de las transducción de señales de la quinasa MAP, el TSD previene también la desnaturalización de la albúmina sérica, lo cual constituye una característica de las drogas anti-inflamatorias no esferoidales, apoyando así el posible papel de las moléculas en el tratamiento de las enfermedades inflamatorias en el proceso de envejecimiento.


Assuntos
Humanos , Compostos de Benzil/farmacologia , Desenho de Fármacos , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , Fluorbenzenos/farmacologia , Phytolaccaceae , Transdução de Sinais/efeitos dos fármacos , Sulfetos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células-Tronco Mesenquimais/efeitos dos fármacos , Degeneração Neural/tratamento farmacológico , Extratos Vegetais/farmacologia
10.
West Indian med. j ; 56(1): 17-21, Jan. 2007.
Artigo em Inglês | LILACS | ID: lil-471843

RESUMO

The data compiled in the present review on dibenzyl trisulphide (DTS) isolated from Petiveria alliacea L (the guinea hen weed or anamu) revealed that the compound and its derivatives could be of tremendous pharmaceutical interest. The mode of action elucidated for DTS revealed that it is a mitogen activated protein extracellular regulated kinases 1 and 2 (MAPKinases erk1 and erk 2) signal transduction molecule. Dibenzyl trisulphide caused hyper-phosphorylation of growth factor induced MAPKinases (erk 1 and erk 2) phosphorylation, a process critical for the improvement of long term memory, and is implicated in neuronal growth. Dibenzyl trisulphide and its derivatives exhibited potent anti-proliferation/cytotoxic activity on a wide range of cancer cell lines. The cytotoxic activity of DTS was increased by 70-1000 fold when bound to albumin in vitro. Dibenzyl trisulphide seems to have a cytokine switching mechanism in which it down regulates cytokines from the Type I helper cells (Th -1 cell) pathway which contained several pro-inflammatory cytokines and up-regulates those on the Type 2 helper cells (Th-2) pathway. The trisulphide up-regulates some reticuloendothelial system parameters eg granulocyte counts and increased thymic and Peyer's patches masses via cell proliferation processes which are known to be regulated via the MAPKinase signal transduction pathway. When the zygotes ofAsternia pectinifera (Starfish) were exposed to DTS at concentration of 10 mM, a dose lethal to all cancer cells tested, it was observed that the sensitive process of protein biosynthesis was not affected Similarly, the proliferation of the HOFA human fibroblast, a noncancerous cell line, was not severely affected by DTS at 8.9 microM over seven days, a concentration also lethal to most cancer cell lines tested The implications of the findings will be highlighted in the present review.


Los datos compilados en el presente estudio sobre el trisulfuro de dibencilo (TSD) aislado a partir de Petiveria alliacea L (yerba de Guinea, ó anamú) revelaron que el compuesto y sus derivados podrían tener extraordinario interés farmacéutico. El modo de acción esclarecido en el TSD, reveló que se trata de una molécula de transducción de señales de proteínas kinasas 1 y 2 (MAP quinasas ERk 1 y 2) reguladas extracelularmente y activadas por mitógenos. El trisulfuro de dibencilo causó hiperfosforilación de la fosforilación de las quinasas MAP (Erk 1 y 2) inducidas mediante factor de crecimiento, un proceso crítico para el mejoramiento de la memoria a largo plazo, y que está implicado en el crecimiento neuronal. El trisulfuro de dibencilo y sus derivados mostraron una poderosa actividad citotóxica y antiproliferativa en una amplia gama de líneas celulares de cáncer. La actividad citotóxica del TSD se incrementaba de 70 á 1000 veces, cuando se vinculaba a la albúmin in vitro. El trisulfuro de dibencilo parece poseer un mecanismo conmutador citoquínico que regula por decremento las citoquinas provenientes de la vía de las células auxiliares de tipo 1 (células Th-1), que contiene varias citoquinas pro-inflamatorias y regula por incremento las de la vía de las células auxiliares de tipo 2 (Th-2). El trisulfuro regula por incremento los parámetros del sistema reticuloendotelial, p.ej. los conteos de granulocitos y el aumento tanto de las masas tímicas como de las masas de placas de Peyer, a través de los procesos de proliferación celular, de los cuales se sabe que son regulados mediante la vía de la transducción de señales de la quinasa MAP. Cuando los cigotos de Asternia pectinifera (estrella de mar) fueron expuestos al TSD a una concentración de 10 mM ­ una dosis letal para todas las células cancerosas sometidas a prueba ­ se observó que el proceso sensible de biosíntesis de la proteína no era afectado. De modo similar, la proliferación del fibroblasto humano HOFA ­ una línea celular no cancerosa ­ no fue afectada severamente por el TSD a 8.9 µM en siete días ­ una concentración letal para la mayoría de las líneas celulares cancerosas sometidas a prueba. Las implicaciones de los hallazgos se pondrán de relieve en el presente estudio


Assuntos
Humanos , Compostos de Benzil/uso terapêutico , Extratos Vegetais , Fitoterapia , Sulfetos/uso terapêutico , Antígenos CD/fisiologia , Caderinas/fisiologia , Compostos de Benzil/farmacologia , Regulação para Cima/fisiologia , Sulfetos/farmacologia , Transdução de Sinais/efeitos dos fármacos
11.
Biocell ; 28(3): 271-277, dic. 2004. ilus, tab
Artigo em Inglês | LILACS | ID: lil-405199

RESUMO

Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber. Rooting percentage did not differ between origins, but higher values were encountered for medium without hormones. Subcultures increased significantly rooting percentage and reduced time to rooting. The leaves from micropropagated plants were thinner, did not exhibit hairs, and had poorly developed palisade parenchyma and less epicuticular waxes. In vitro leaves had lower stomatal density and their stomata were less functional when compared to acclimated leaves. A repopulation program of Lycium chilense based on microcutting culture, specialy using subcultures, is feasible.


Assuntos
Aclimatação/fisiologia , Técnicas de Cultura de Células , Lycium , Lycium/genética , Morfogênese/fisiologia , Compostos de Benzil/farmacologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/ultraestrutura , Ácidos Indolacéticos , Lycium/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Ácidos Naftalenoacéticos , Raízes de Plantas , Ploidias , Purinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta
12.
West Indian med. j ; 53(4): 208-219, Sept. 2004.
Artigo em Inglês | LILACS | ID: lil-410433

RESUMO

Sixty natural products belonging to the following structural classes: artemisinins, coumarins, flavonoids, tannins, tetrahydroberberine alkaloids, tetracyclic triterpenes, tetranortriterpenoids and polysulphides were screened against the human SH-SY5Y neuroblastoma cell line revealing differences in their effects on cell morphology and in anti-proliferation/cytotoxic activity. Based on the data obtained, dibenzyl trisulphide is the most effective anti-proliferative/cytotoxic compound. In addition, we hereby propose the human SH-SY5Y cell line as a sensitive and uncomplicated in vitro test system for detecting compounds with potential anti-proliferation/cytotoxic activity


Assuntos
Humanos , Antineoplásicos/farmacologia , Compostos de Benzil/farmacologia , Extratos Vegetais/farmacologia , Neuroblastoma/patologia , Sulfetos/farmacologia , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Extratos Vegetais/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos
14.
Gac. méd. Méx ; 129(3): 201-5, mayo-jun. 1993. ilus
Artigo em Espanhol | LILACS | ID: lil-177111

RESUMO

Se reporta un estudio clínico, doble ciego, controlado, para evaluar la eficacia y seguridad de ivermectina por vía bucal a la dosis de 200 mcg/kg de peso para el tratamiento de la escabiasis, efectuado en 55 pacientes. Los resultados informaron que 26 pacientes (79.3 por ciento) curaron con ivermectina en su primera visita de control, en comparación con cuatro (16 por ciento) del grupo que recibió placebó (X²= 77.07, p<0.001). Al final 37 pacientes de 50 (74 por ciento tratados con ivermectina curaron comparados con cuatro de 26 (16 por ciento) manejados con placebo. Esta diferencia es significativa (X²=23.66, p<0.001). Se concluyó que la ivermectina por vía oral efectiva y segura en el tratamiento de la escabiasis


Assuntos
Humanos , Masculino , Feminino , Adolescente , Antinematódeos/uso terapêutico , Compostos de Benzil/uso terapêutico , Dermatopatias Parasitárias/fisiopatologia , Infestações por Ácaros/fisiopatologia , Ivermectina/administração & dosagem , Oncocercose/terapia , Placebos/uso terapêutico , Escabiose/parasitologia
16.
Rev. farm. bioquim ; 5(1): 31-8, jan.-jun. 1983.
Artigo em Português | LILACS | ID: lil-139430

RESUMO

O p-benziloxialilbenzeno (O-benzilchavicol) foi obtido por síntese envolvendo oito etapas e submetido a testes farmacológicos. Apresentou efeito anticonvulsivante e potenciou fortemente o tempo de sono induzido pelo pentobarbital.


Assuntos
Animais , Anticonvulsivantes/uso terapêutico , Compostos de Benzil/farmacologia
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