Morphoanatomic characterization of the stem and the leaf of Tabernaemontana catharinensis A. DC (Apocynaceae) and antimutagenic activity of its leaves / Caracterização morfoanatômica do caule e da folha de Tabernaemontana catharinensis A. DC (Apocynaceae) e atividade antimutagênica de suas folhas

ABSTRACT Tabernaemontana catharinensis A. DC (Apocynaceae) is used as a medicinal plant by the population. In order to contribute to the safe use of the plant as herbal medicine, this study aimed to morphoanatomically characterize the aereal vegetative organs of T. catharinensis and to evaluate the leaves’ mutagenic and antimutagenic activities. Histological blades of leaves and stem of T. catharinensis were performed; the methionine system (methG1) and Aspergillusnidulans conidia germination analysis were employed for mutagenic and antimutagenic evaluation. The morphoanatomic analysis did not show trichomes in the stem, petiole and leaf. Besides, it was observed both the presence of bi-collateral bundles - except in the foliar apex where the bundles were from the collateral type - as well as anamphistomatic leaf with paracyte stomata and sub-epidermal layer in the region of the leaf edges. The mutagenicity/antimutagenicity trial indicated a significant decrease of mutation frequency in comparison with the control group and showed that the T. catharinensis had antimutagenic activity within the type, time and form of treatment. Since the germination test showed that the conidia germination was accelerated from the bud phase, activities at the cell cycle level and polarized growth proved to be possible. The morphoanatomic analysis of the leaf and stem associated with the mutagenic and antimutagenic analyses contributes to the safe use of the plant by humans and also for the quality control of a possible phytotherapeutic drug.

RESUMO Tabernaemontana catharinensis A. DC (Apocynaceae) é utilizada como planta medicinal pela população. A fim de contribuir para o uso seguro da planta como medicinal, este trabalho teve como objetivo caracterizar morfoanatomicamente os órgãos vegetativos aéreos de T. catharinensis e avaliar a atividade mutagênica e antimutagênica de suas folhas. Foram realizados cortes histológicos da folha e do caule de T. catharinensis e, para a avaliação mutagênica e antimutagênica, foi utilizado o sistema metionina (methG1) e análise da germinação de conídios em Aspergillus nidulans. A análise morfoanatômica evidenciou a ausência de tricomas no caule, pecíolo e folha; presença de feixes bicolaterais, com exceção no ápice foliar cujos feixes são do tipo colateral; folha anfiestomática com estômatos paracíticos e camada subepidérmica na região do bordo foliar. O ensaio de mutagenicidade/antimutagenicidade mostrou uma diminuição significativa da frequência de mutação em relação ao controle, indicando que nesse tipo, tempo e forma de tratamento, T. catharinensis apresentou atividade antimutagênica. O ensaio de germinação evidenciou que houve aceleração da germinação dos conídios, a partir da fase de botão, indicando uma possível atuação em nível de ativação de ciclo celular e crescimento polarizado. A análise morfoanatômica da folha e do caule associados à análise mutagênica e antimutagênica, contribuem para o uso seguro da planta pela população e para o controle de qualidade de um possível fitoterápico.

Methionine Enhances the Contractile Activity of Human Colon Circular Smooth Muscle In Vitro

Effective drug to manage constipation has been unsatisfactory. We sought to determine whether methionine has effect on the human colon. Human colon tissues were obtained from the specimens of colon resection. Microelectrode recording was performed and contractile activity of muscle strips and the propagation of the contractions in the colon segment were measured. At 10 microM, methionine depolarized the resting membrane potential (RMP) of circular muscle (CM) cells. In the CM strip, methionine increased the amplitude and area under the curve (AUC) of contractions. In the whole segment of colon, methionine increased the amplitude and AUC of the high amplitude contractions in the CM. These effects on contraction were maximal at 10 microM and were not observed in longitudinal muscles in both the strip and the colon segment. Methionine reversed the effects of pretreatment with sodium nitroprusside, tetrodotoxin and Nw-oxide-L-arginine, resulting in depolarization of the RMP, and increased amplitude and AUC of contractions in the muscle strip. Methionine treatment affected the wave pattern of the colon segment by evoking small sized amplitude contractions superimposed on preexisting wave patterns. Our results indicate that a compound mimicking methionine may provide prokinetic functions in the human colon.

Antioxidant Effects of Sulfur-Containing Amino Acids

Sulfur is an essential element for the entire biological kingdom because of its incorporation into amino acids, proteins and other biomolecules. Sulfur atoms are also important in the iron-containing flavoenzymes. Unlike humans, plants can use inorganic sulfur to synthesize sulfur-containing amino acids. Therefore, plants are an important source of sulfur for humans. Sulfur-containing compounds are found in all body cells and are indispensable for life. Some of sulfur-containing antioxidant compounds are, cysteine, methionine, taurine, glutathione, lipoic acid, mercaptopropionylglycine, N-acetylcysteine, and the three major organosulfur compounds of garlic oil, diallylsulfide, diallyldisulfide and diallyltrisulfide. In a comparison of the structure-function relationship among these sulfur-containing antioxidant compounds, dihydrolipoic acid (the reduced form of LA) is the most effective antioxidant. Dihydrolipoic acid contains two sulfhydryl groups and can undergo further oxidation reaction to form lipoic acid. The antioxidative activities of sulfur-containing compounds follow a general trend, the more highly reduced forms are stronger antioxidants and the number of sulfur atoms determine, at least in part, their modulatory activites on the glutathione related antioxidant enzymes. In this article, the antioxidant effects and the antioxidative activities, of sulfur-containing amino acids, are reviewed. In addition, the general antioxidant effects and the structure-function relationship of some sulfur-containing compounds are also reviewed.

Paracetamol and conventional antimalarial drugs induced hepatotoxicity and its protection by methionine in rats.

Hepatotoxicity, induced in rats, by treatment with high doses of paracetamol and chloroquine was confirmed by estimating blood transaminase levels. Hepatoprotective effect was determined by administering combination of methionine (10% of paracetamol/chloroquine, p.o.) and hepatotoxic drugs quinine. The results were confirmed by histopathological examination of liver. Paracetamol (7 g/kg) and chloroquine (970 mg/kg) administration increased significantly the transaminase levels. Methionine alone did not produced any change. Hepatonecrosis induced by paracetamol, chloroquine alone and their combinations and its protection with methionine was revealed by histopathological study whereas the combination of paracetamol and methionine showed no significant histopathological difference when compared to the normal liver section. The results reveal that, methionine significantly prevented the rise in transaminases levels produced by hepatotoxic doses of paracetamol and chloroquine. But, to prevent occasional cases of paracetamol overdosage, it is not advisable to give methionine concurrently with paracetamol to patients who are taking paracetamol therapeutically.

Beneficial effects of methionine on the testicular and hepatic toxicity of thiocarbamate herbicide in adult male albino rats

This study was conducted on 165 adult male albino rats divided into seven groups: Group I included negative control, Group II received distilled water, Group III received corn oil, Group IV [IVa and IVb] received methionine, Group V [Va and Vb] received thiocarbamate, Group VI [VIa and Vib] received methionine 1/2 hour after thiocarbamate and Group VII [VIIa and VIIb] received methionine two hours after thiocarbamate. Groups IVa, Va, VIa and VIIa were sacrificed after 48 hours; while groups I, II, III, IVb, Vb, VIb and VIIb were sacrificed after three weeks. Serum testosterone, estimation of testis weight, liver function tests [AST, ALT, ALP and T. Bil], histochemical and histopathological examination were done. The results showed that thiocarbamate caused testicular and hepatic toxicity and its severity increased by time. Methionine was found to be a promising protective agent against such toxicity through glutathione dependent mechanism. Also, the earlier it was given, the better protection could be offered

Producción y sensibilidad a microcinas en cepas de Pseudomonas aeruginosa / Pseudomonas aeruginosa microcins: production and sensibility

Se aislaron cepas de Pseudomonas aeruginosa de distintos procesos infecciosos con el objeto de estudiar la capacidad de producir microcinas y la sensibilidad a las elaboradas por otras cepas. Se investigaron por el método de estrías cruzadas en condiciones mínimas de crecimiento y en agar nutritivo, siendo más adecuado el primero. Se analizó el efecto de la presencia de metionina en medio mínimo. El tamaño molecular de las bacteriocinas se estimó con membranas capaces de retener moléculas mayores de 8000 daltons. Los resultados obtenidos indicaron una alta incidencia de cepas productoras de microcinas (85,7 por ciento). La sensibilidad a las mismas fue variada desde 0 a 10 cepas susceptible. Al mantener P. aeruginosa en el laboratorio se redujo el espectro de actividad, mientras que las recientemente aisladas inhibieron mayor número de cepas. Se observó también que disminuyó la sensibilidad a microcinas al conservarse las cepas por más de seis meses. Es conveniente realizar tipificación mediante microcinas con bacterias mantenidas por poco tiempo en cultivo

Restoration of tissue antioxidants and prevention of renal stone deposition in vitamin B6 deficient rats fed with vitamin E or methionine.

Observed loss in body weight gain, increased lipid peroxidation reaction, decreased concentrations of antioxidants, ascorbic acid, alpha-tocopherol and reduced glutathione and antioxidant enzymes, glutathione peroxidase and catalase and increased concentration of hydroperoxides and hydroxyl radicals in vitamin B6 deficient rat liver [J Nutri Biochem, 2 (1991) 245] and kidney [Biochem International, 21 (1991) 599] were nearly normalized on feeding with vitamin E or methionine. Accumulation of oxalate and calcium during vitamin B6 deficiency was abolished by feeding vitamin E or methionine. Calcium oxalate deposition observed in vitamin B6 deficient kidney was completely prevented when fed along with vitamin E or methionine. However the hyperoxaluria and hypercalciuria persisted even after feeding with vitamin E or methionine.

Curative effect of methionine on certain enzymes of chick kidney cortex under lanthanum toxicity situation.

Acute single dose administration of lanthanum chloride (250 mg/kg body wt, ip) to chicks have been found to alter the levels of enzymes of the antioxidant defence system of chick renal cortex fractions. Such changes involved significant decrease in activities of glucose-6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase and catalase of kidney epithelial cells. However glutathione-S-transferase activity was not altered. Glutathione and total thiol contents were decreased while lipoperoxidative reactions in kidney-cortex was significantly enhanced. The data indicate that amelioration of lanthanum toxicity condition by methionine supplementation may be due to the methionine serving as a precursor of glutathione.

Restoration of antioxidants in liver by methionine feeding in experimental rat urolithiasis.

The effect of methionine or citrate on antioxidant defense system has been studied in urolithic rat. Liver weight and its protein concentration did not change in the rats fed with calculi producing diet (CPD) when compared to normal diet fed rats. Feeding rats along with citrate (c-CPD) or methionine (m-CPD) improved their body weight gain. Liver microsomes and mitochondria fractions of CPD and c-CPD fed groups showed increased susceptibility for lipid peroxidation in presence of ascorbate and t-butyl hydroperoxide when compared to either control or m-CPD fed groups. Increased superoxide dismutase and xanthine oxidase activities, decreased catalase, glutathione peroxidase and glucose-6-phosphate dehydrogenase activities, decreased concentrations of reduced glutathione, total thiols, ascorbic acid and vitamin-E and increased formation of hydroxyl radical, hydroperoxides and diene conjugates were observed in the liver of both CPD fed group as well as c-CPD fed group. Except SOD and xanthine oxidase, all other parameters were normalized in m-CPD fed group. This suggested that feeding methionine reduced the susceptibility for lipid peroxidation by restoration of the level of free radical scavengers.

Calidad nutricional de la proteína de la falsa lenteja (Vicia sativa ssp. abovata (Ser) Gaudin) / Nutritional quality of the protein of the false lentil (Vicia sativa ssp. abovata (Ser) Gaudin)

La falsa lenteja (Vicia sativa) es una leguminosa que se desarrolla en forma rústica en la zona central de Chile. Es consumida por la población rural, como lenteja, y también se utiliza en la alimentación animal. El objetivo del presente trabajo fue estudiar su valor nutricional con énfasis en la calidad biológica, digestibilidad de la proteína y características de su fibras dietética. Se estudiaron semillas proporcionadas por el Instituto de Investigaciones Agropecuarias (INIA), en las que se determinó la composición química, fibra dietética, calidad biológica de la proteína mediante el PER, y digestibilidad aparente y verdadera. Destacó la alta concentración de proteína )23.5%), superior a las legunosas de consumo habitual. El porcentaje de fibra dietética es de 14.2%, con 13.2% de fibra insolubre y 1.0% de la soluble. El PER mostró valores de 1.30 ñ 0.44 para el material crudo y de 1.32 ñ 0.37 en el cocido, la suplementación con 0.15% de DL - metionina produjo un incremento a 2.43 ñ 0.32, siendo el valor de la caseína de 3.02 ñ 0.36. la digestibilidad verdadera fue de 76.2 ñ 2.0 en el material crudo y de 73.8 ñ 2.2 en el cocido. Estos resultados demuestran que la falsa lenteja no presenta tóxicos termolábiles que son frecuentes en las leguminosas. Sin embargo, se ha descrito la presencia de derivados de la cianoalanina, que tienen un efecto neurotóxico. El presente estudio sugiere que la falsa lenteja es un alimento con características nutricionales promisoras. En consecuencia, es pues imprescindible profundizar los estudios tendientes a dilucidar la toxicidad real de este alimento

Location of the supressor of meth A17 mutation in the 30 mutant of Aspergillus nidulans

O mutante 30 foi selecionado principalmente pelo seu comportamento mitótico e meiótico, muito peculiar. A alta freqüência de recombinaçäo no intervalo meth-w do cromossomo II é devido a um supressor recessivo e silencioso de meth A17. A análise mitótica mostrou uma forte pressäo seletiva contra os cromossomos I e VII. A morfologia da linhagem suprimida, em um meio sem metionina, permitiu a determinaçäo da localizaçäo da mutaçäo sup 30 no cromossomio VII ligado ao locus nic B8 (26,8%)

Estudo do concentrado proteico da folha de mandioca: obtençäo, análisis químicas e suplementaçäo com aminoácidos / Protein concentrate of manioc leaf: obtention, chemical analyses and supplementation with amino acids

O presente trabalho teve por objetivo obter um concentrado proteico de folhas de mandioca através de modificaçöes na metodologia já existente. O valor nutricional da folha de mandioca e do concentrado proteico foi avaliado através de análises químicas, ensaio biológico e suplementaçäo da proteína tanto do concentrado como da folha com os aminoácidos limitantes lisina e metionina.. Dos resultados obtidos foram sugeridas as seguintes conclusöes: - A folha de mandioca e o concentrado proteico da folha apresentaram um teor proteico elevado, 25.2% e 34%, respectivamente. - Ensaios biológicos tanto do concentrado como da folha com o aminoácido lisina mais metionina mostrou ser eficiente, dando maiores valores para PER, NPU e digestibilidade. - A adiçäo do aminoácido lisina näo mostrou ter nunhum efeito significativo na melhora do valor nutricional da proteína. - Exames anátomo patológico dos órgäos dos animais näo revelaram nenhuma alteraçäo, indicando näo haver fatores tóxicos na folha e no concentrado