Estudio de los parámetros de calidad de la especie vegetal Urtica urens L. recolectada en la provincia Ingavi del Departamento de La Paz / Study of the quality parameters of Urtica urens L. collected in the Ingavi province of the Department of La Paz

INTRODUCCIÓN: el incremento en el consumo de recursos naturales para el alivio de diferentes enfermedades ha llevado a varios países a diseñar mecanismos de control, que garanticen mediante métodos físico-químicos la calidad del material vegetal que se utilizará como materia prima para las preparaciones farmacéuticas y/o como medicina tradicional. La falsificación, la mala calidad o la adulteración en estos productos constituyen una grave amenaza a la seguridad del consumidor. El estudio de los parámetros de calidad de una especie vegetal nos permite reconocer su identidad, su pureza, así como el contenido de principios activos, que garanticen su calidad, eficacia y seguridad. U. urens L. (Urticáceas) es una especie ampliamente distribuida en América del Sur, en Bolivia se encuentra en diferentes tipos de terreno, en el Cantón Chama de la provincia Ingavi es ampliamente utilizada por sus pobladores principalmente en el tratamiento de enfermedades inflamatorias e urinarias. OBJETIVO: estudiar los parámetros de calidad de la especie vegetal U. urens L. recolectada en el Cantón Chama de la provincia Ingavi del Departamento de La Paz. MATERIALES Y MÉTODOS: se realizó el análisis de las características organolépticas, para el análisis micrográfico se utilizó el material vegetal seco reducido a polvo, el análisis físico químico se realizó por métodos oficiales AOAC. Se obtuvieron cuatro tipos de extractos, extracto etéreo, diclorometánico, etanólico y acuoso, en ellos se determinó la composición cualitativa de grupos mayoritarios de moléculas mediante la técnica Screening Fitoquímico y se elaboró el perfil cromatográfico de la especie vegetal. RESULTADOS: el estudio reveló la presencia de pelos urticantes unicelulares y pluricelulares, los parámetros fisicoquímicos concuerdan con los valores referencia encontrados en las principales farmacopeas. El screening fitoquímico cualitativo reveló la presencia mayoritaria de taninos, alcaloides, compuestos reductores, esteroles, flavonoides y cumarinas. Adicionalmente, el perfil cromatográfico reveló la presencia de diferentes manchas en fases móviles asociadas principalmente con flavonoides. CONCLUSIONES: el estudio de los parámetros de calidad de Urtica urens L aporta con información para su identificación y establece la presencia de determinados compuestos que serían los responsables de la actividad farmacológica atribuida por su uso tradicional.(AU)

INTRODUCTION: the increase in the consumption of natural resources for the relief of different diseases has led several countries to design control mechanisms that guarantee through physical-chemical methods the quality of the plant material that will be used as raw material for pharmaceutical preparations and / or as traditional medicine. Counterfeiting, poor quality, or adulteration in these products pose a serious threat to consumer safety. The study of the quality parameters of a plant species allows us to recognize its identity, its purity, as well as the content of active principles, which guarantee its quality, efficacy and safety. U. urens L. (Urticaceae) is a widely distributed species in South America, in Bolivia it is found in different types of terrain, in the Canton Chama of the Ingavi province it is widely used by its inhabitants mainly in the treatment of inflammatory and urinary diseases. OBJECTIVE: to study the quality parameters of the plant species U. urens L. collected in the Canton Chama of the Ingavi province of the Department of La Paz. MATERIALS AND METHODS: the analysis of the organoleptic characteristics was carried out, for the micrographic analysis the dry plant material reduced to powder was used, the physical-chemical analysis was carried out by official AOAC methods. Four types of extracts were obtained, ethereal, dichloromethane, ethanolic and aqueous extract, in which the qualitative composition of major groups of molecules was determined by the phytochemical screening technique and the chromatographic profile of the plant species was elaborated. RESULTS: the study revealed the presence of unicellular and multicellular stinging hairs, the physicochemical parameters agree with the reference values found in the main pharmacopoeias. The qualitative phytochemical screening revealed the majority presence of tannins, alkaloids, reducing compounds, sterols, flavonoids and coumarins. Additionally, the chromatographic profile revealed the presence of different spots in mobile phases mainly associated with flavonoids. CONCLUSIONS: The study of the quality parameters of Urtica urens L provides information for its identification and establishes the presence of certain compounds that would be responsible for the pharmacological activity attributed to its traditional use.(AU)

The SREBP (Sterol Regulatory Element-Binding Protein) pathway: a regulatory bridge between carotenogenesis and sterol biosynthesis in the carotenogenic yeast Xanthophyllomyces dendrorhous

Xanthophyllomyces dendrorhous is a basidiomycete yeast that naturally produces the red-orange carotenoid astaxanthin, which has remarkable antioxidant properties. The biosynthesis of carotenoids and sterols share some common elements that have been studied in X. dendrorhous. For example, their synthesis requires metabolites derived from the mevalonate pathway and in both specific pathways, cytochrome P450 enzymes are involved that share a single cytochrome P450 reductase, CrtR, which is essential for astaxanthin biosynthesis, but is replaceable for ergosterol biosynthesis. Research on the regulation of carotenoid biosynthesis is still limited in X. dendrorhous; however, it is known that the Sterol Regulatory Element-Binding Protein (SREBP) pathway, which is a conserved regulatory pathway involved in the control of lipid metabolism, also regulates carotenoid production in X. dendrorhous. This review addresses the similarities and differences that have been observed between mammal and fungal SREBP pathways and what it is known about this pathway regarding the regulation of the production of carotenoids and sterols in X. dendrorhous.

Antidiabetic activities of alkaloids isolated from medicinal plants

Diabetes mellitus is a metabolic disorder affecting a great part of population around the world. It is the fifth leading death causing disease in the world and its cases are increasing day by day. Traditional medicine is thought to have promising future in the treatment of diabetes mellitus. In contrast to synthetic drugs phytochemicals are considered to be free from side effects. As one of the main class of natural products, alkaloids and their derivatives have been widely used as sources of pharmacological agents against a variety of medical problems. Many studies confirmed the role of alkaloids in the management of diabetes and numerous alkaloids isolated from different medicinal plants were found active against diabetes. Like other natural products, alkaloids regulate glucose metabolism either by inhibiting or inducing multiple candidate proteins including AMP-activated protein kinase, glucose transporters, glycogen synthase kinase-3, sterol regulatory element-binding proteins 1, glucokinase, glucose-6-phosphatase, acetyl-CoA carboxylase among the others. A comprehensive review of alkaloids reported in the literature with anti-diabetic activities and their target enzymes is conducted, with the aim to help in exploring the use of alkaloids as anti-diabetic agents. Future work should focus on rigorous clinical studies of the alkaloids, their development and relevant drug targets.

Chlorella sorokiniana and Chlorella minutissima exhibit antioxidant potentials, inhibit cholinesterases and modulate disaggregation of ß-amyloid fibrils

BACKGROUND: Microalgae are aquatic chlorophyll-containing organisms comprising unicellular microscopic forms, and their biomasses are potential sources of bioactive compounds, biofuels and food-based products. However, the neuroprotective effects of microalgal biomass have not been fully explored. In this study, biomass from two Chlorella species was characterized, and their antioxidant, anticholinesterase and anti-amyloidogenic activities were investigated. RESULTS: GC­MS analysis of the extracts revealed the presence of some phenols, sterols, steroids, fatty acids and terpenes. Ethanol extract of Chlorella sorokiniana (14.21 mg GAE/g) and dichloromethane extract of Chlorella minutissima (20.65 mg QE/g) had the highest total phenol and flavonoid contents, respectively. All the extracts scavenged 2,2-diphenyl-1-picrylhydrazyl, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) and hydroxyl radicals. The highest metal chelating activity of the extracts was observed in the ethanol extracts of C. minutissima (102.60 µg/mL) and C. sorokiniana (107.84 µg/mL). Furthermore, the cholinesterase inhibitory activities of the extracts showed that ethanol extract of C. sorokiniana (13.34 µg/mL) exhibited the highest acetylcholinesterase inhibitory activity, while dichloromethane extract of C. minutissima (11.78 µg/mL) showed the highest butyrylcholinesterase inhibitory activity. Incubation of the ß-amyloid protein increased the aggregation of amyloid fibrils after 96 h. However, ethanol extract of C. sorokiniana and C. minutissima inhibited further aggregation of Aß1­42 and caused disaggregation of matured protein fibrils compared to the control. This study reveals the modulatory effects of C. sorokiniana and C. minutissima extracts on some mediators of Alzheimer's disease and provides insights into their potential benefits as functional food, nutraceutics or therapeutic agent for the management of this neurodegenerative disease.

Pharmacological importance of Manilkara zapota and its bioactive constituents / Importancia farmacologica de Manilkara zapota y sus constituyentes bioactivos

Manilkara zapota (Sapotaceae), commonly known as Sapodilla, is widely known for its delicious fruit. Various parts of this plant are also used in folk medicine to treat a number of conditions including fever, pain, diarrhoea, dysentery, haemorrhage and ulcers. Scientific studies have demonstrated analgesic, anti-inflammatory, antioxidant, cytotoxic, antimicrobial, antidiarrheal, anti-hypercholesteremic, antihyperglycemic and hepatoprotective activities in several parts of the plant. Phytochemical studies have revealed the presence of phenolic compounds including protocatechuic acid quercitrin, myricitrin, catechin, gallic acid, vanillic acid, caffeic acid, syringic acid, coumaric acid, ferulic acid, etc. as main constituents of the plant. Several fatty acids, carotenoids, triterpenes, sterols, hydrocarbons and phenylethanoid compounds have also been isolated from M. zapota. The present review is a comprehensive description focused on pharmacological activities and phytochemical constituents of M. zapota.

Manilkara zapota (Sapotaceae), comúnmente conocida como Sapodilla, es ampliamente conocida por su delicioso fruto. Variadas partes de esta planta se usan en medicina popular para tratar una serie de afecciones, como fiebre, dolor, diarrea, disentería, hemorragia y úlceras. Estudios científicos han demostrado actividad analgésica, antiinflamatoria, antioxidante, citotóxica, antimicrobiana, antidiarreica, antihipercolesterolémica, antihiperglucémica y hepatoprotectora en diferentes partes de la planta. Los estudios fitoquímicos han revelado la presencia de compuestos fenólicos que incluyen ácido protocatechúico, quercitrina, miricitrina, catequina, ácido galico, ácido vanílico, ácido cafeico, ácido sirínico, ácido cumárico, ácido fúnico y ácido ferúlico como componentes principales de la planta. Varios ácidos grasos, carotenoides, triterpenos, esteroles, hidrocarburos y compuestos feniletanoides también han sido aislados de M. zapota. La presente revisión es una descripción exhaustiva centrada en las actividades farmacológicas y los constituyentes fitoquímicos de M. zapota.

Antioxidant capacity of Momordica charantia extract and its protective effect on testicular damage in valproic acid-induced rats / Capacidad antioxidante del extracto de Momordica charantia y su efecto protector sobre el daño testicular en ratas inducidas con ácido valproico

Although Momordica charantia (MC) has preventive effects on tissue injuries, antioxidant capacity and protective effect of MC pulp and peel (MCP) on valproic acid (VPA)-testicular damage have never been reported. Fresh MCPs were aqueous extracted and determined for antioxidant capacity and momordicine I level by HPLC. Male rats were divided into 5 groups (control, VPA (500 mg/kgBW), MCP20/40/ or 80 mg/kgBW+VPA). In 30 experimental days, animals were pretreated with different doses of MCPs for 20 days before VPA injection for 10 consecutive days. Sperm concentration, testosterone hormone, and testicular histology of all groups were investigated. Expressions of testicular tyrosine phosphorylated and steroidogenic acute regulatory (StAR) proteins were examined by Western blot. Results showed that MCP contains TPC (39.24±0.65 ug/mg garlic acid), antioxidant capacities (FRAP=33.08±0.21 ug/ mg ascorbic acid equivalent, IC50 of DPPH=389.8±3.20 ug/ml), and momordicine I (404.9 mg/g MCP). Sperm concentration in MCP80+VPA group was increased as compared to VPA group. Testosterone level in MCP treated groups was significantly increased. MCP protected testicular damage and could prevent the decrease of StAR and a 50-kDa phosphorylated protein expression in VPAtreated testis. In conclusion, MCP has antioxidant activities and can prevent male reproductive toxicity in VPA-induced rats.

A pesar que la Momordica charantia (MC) tiene efectos preventivos sobre las lesiones en los tejidos, capacidad antioxidante y un efecto protector de la pulpa y la cáscara de MC (CMC) sobre el ácido valproico (AVP), aún no se ha informado efectos sobre el daño testicular. Las CMC frescas fueron extraídas de forma acuosa y se determinó la capacidad antioxidante y el nivel de Momordicina I por HPLC. Las ratas machos se dividieron en 5 grupos: control, AVP (500 mg/kg de peso corporal), CMC20 / 40 / u 80 mg/kg de peso corporal + AVP . En 30 días experimentales, los animales fueron pretratados con diferentes dosis de CMC durante 20 días antes de la inyección de AVP durante 10 días consecutivos. Se investigó la concentración de espermatozoides, la hormona testosterona y la histología testicular de todos los grupos. Las expresiones de proteínas reguladoras agudas (StAR) fosforiladas con tirosina y esteroidogénicas testiculares se examinaron mediante inmunotransferencia de tipo Western. Los resultados mostraron que CMC contiene TPC (39.24 ± 0.65 ug / mg de ácido de ajo), capacidades antioxidantes (FRAP = 33.08 ± 0.21 ug / mg de ácido ascórbico equivalente, IC50 de DPPH = 389.8 ± 3.20 ug / ml) y momordicina I (404.9 mg) / g CMC). La concentración de esperma en el grupo MCP80 + AVP aumentó en comparación con el grupo AVP. El nivel de testosterona en los grupos tratados con CMC aumentó significativamente. La CMC protegió el daño testicular y pudo prevenir la disminución de StAR y una expresión de proteína fosforilada de 50 kDa en los testículos tratados con AVP. En conclusión, la CMC tiene efectos antioxidantes y puede prevenir la toxicidad reproductiva en ratas machos inducidas por VPA.

MOLLUSCICIDAL AND LARVICIDAL ACTIVITIES OF Atriplex inflata AERIAL PARTS AGAINST THE MOLLUSK Galba truncatula, INTERMEDIATE HOST OF Fasciola hepatica / Atividade moluscicida e larvicida das partes aéreas de Atriplex inflata contra o molusco Galba truncatula, hospedeiro intermediário da Fasciola hepatica

Fasciolosis is a widespread parasitosis of farm live-stock in many developing countries. For this reason, it is necessary to search for new substances against parasitic diseases caused by flukes. Indeed, a wide variety of terrestrial plants have been subjected to chemical and pharmacological screening in order to discover their potential for human medicinal use. The molluscicidal and larvicidal activities of Atriplex inflata were tested on Galba truncatula and Fasciola hepatica larval stages infecting this snail in Tunisia. Phytochemical tests were conducted on extracts in order to establish a meaningful relationship with molluscicidal and larvicidal activities. The molluscicidal activity was evaluated by subjecting snails to sample aqueous solutions. Accordingly, hexane, ethyl acetate, methanol and methanol-water (8:2, v-v) were used as extraction solvents. As a result, hexane and ethyl acetate extracts showed potent activity, according to the World Health Organization, giving LC50 = 7.59 mg/L and 6.69 mg/L for hexane extracts of leaves and fruits, respectively. Ethyl acetate extracts gave LC50 = 5.90 mg/L and 7.32 mg/L for leaves and fruits, successively. Molluscicidal activities of powders were less potent on snails, but active according to the World Health Organization. Hexane and ethyl acetate extracts from leaves and fruits gave potent larvicidal activities with a delay rate exceeding 45.50% (45.50- 98.92%). Phytochemical tests showed that these activities may be attributed to the presence of triterpenoids and/or sterols.

Fasciolose é uma parasitose generalizada que ocorre em animais de fazendas em muitos países em desenvolvimento. Por esta razão, é necessária a busca de novas substâncias contra as doenças parasitárias causadas por vermes. De fato, uma grande variedade de plantas terrestres foi objeto de testes farmacológicos e químicos a fim de descobrir o seu potencial para utilização em terapêutica humana. As atividades moluscicida e larvicida de Atriplex inflata foram testadas contra estágios larvários de Galba truncatula e Fasciola hepatica infectando este caracol na Tunísia. Testes fitoquímicos foram realizados com extratos a fim de estabelecer uma relação significativa com as atividades moluscicida e larvicida. A atividade moluscicida foi avaliada submetendo os caracóis a soluções aquosas. Conforme o caso, hexano, acetato de etilo, metanol e metanol-água (8:2, v-v) foram utilizados como solventes de extração. Como resultado, hexano e extratos de acetato apresentaram atividades potentes de acordo com a Organização Mundial de Saúde, resultando em LC50 = 7,59 mg/L e 6,69 mg/L para extratos de hexano de folhas e frutos, respectivamente. Extratos de acetato de etilo resultaram em LC50 = 5,90 mg/L e 7,32 mg/L para as folhas e frutos sucessivamente. Atividades moluscicidas das substâncias sob a forma de pó foram menos potentes em caracóis, mas ativas de acordo com a Organização Mundial de Saúde. Hexano e extratos de acetato de folhas e frutos apresentaram atividade larvicida potente, com uma taxa de atraso superior a 45,50% (45,50-98,92%). Testes fitoquímicos mostraram que estas atividades podem ser atribuídas à presença de triterpenóides e/ou esteróis.

Compositional studies and biological activities of some mash bean (Vigna mungo (L) Hepper) cultivars commonly consumed in Pakistan

BACKGROUND: In recent years, the desire to adopt a healthy diet has drawn attention to legume seeds and food products derived from them. Mash bean is an important legume crop used in Pakistan however a systematic mapping of the chemical composition of mash bean seeds is lacking. Therefore seeds of four mash bean (Vigna mungo (L.) Hepper, family Leguminoseae) cultivars (NARC-Mash-1, NARC-Mash-2, NARC-Mash-3, NARC-Mash-97) commonly consumed in Pakistan have been analyzed for their chemical composition, antioxidant potential and biological activities like inhibition of formation of advanced glycation end products (AGE) activity and tyrosinase inhibition activity. RESULTS: The investigated cultivars varied in terms of biochemical composition to various extents. Mineral composition indicated potassium and zinc in highest and lowest amounts respectively, in all cultivars. The amino acid profile in protein of these cultivars suggested cysteine is present in lowest quantity in all cultivars while fatty acid distribution pattern indicated unsaturated fatty acids as major fatty acids in all cultivars. All cultivars were found to be rich source of tocopherols and sterols. Fourier transform infrared spectroscopy (FTIR) fingerprints of seed flour and extracts indicated major functional groups such as polysaccharides, lipids, amides, amines and amino acids. Results indicated that all investigated cultivars possessed appreciable antioxidant potential. CONCLUSIONS: All cultivars are rich source of protein and possess sufficient content of dietary fiber, a balanced amino acid profile, low saturated fatty acids and antioxidant capacity that rationalizes many traditional uses of seeds of this crop besides its nutritional importance. The collected data will be useful for academic and corporate researchers, nutritionists and clinical dieticians as well as consumers. If proper attention is paid, it may become an important export commodity and may fetch considerable foreign exchange for Pakistan.

Papel do colesterol exógeno nos mecanismos de adaptação de Leishmania spp a condições de estresse metabólico e farmacológico / Role of exogenous cholesterol in Leishmania spp adaptation mechanisms to conditions of metabolic and pharmacological stress

Os tripanossomatídeos não sintetizam o colesterol e sim esteróis com o esqueleto ergostano, porém um percentual significativo de colesterol exógeno é encontrado em todas as espécies de Leishmania, sugerindo um papel biológico para esta molécula. Esta tese tem como objetivo estudar a importância do uso de colesterol para Leishmania spp. em várias situações, avaliando o potencial deste sistema como um possível alvo farmacológico. A atividade dos inibidores de biossíntese de ergosterol associado com inibidores de transporte de colesterol derivado de LDL, foi avaliada em promastigotas e amastigotas intracelulares. A associação entre LBqT01 e cetoconazol, miconazol ou terbinafina mostrou sinergia. A associação entre a imipramina ou progesterona e cetoconazol ou terbinafina indicaram um efeito aditivo. O cetoconazol e miconazol demonstraram uma diminuição de até duas vezes o valor de IC50 nas formas amastigotas, quando combinado com os inibidores de transporte de colesterol. Foi observado também alteração da biossíntese de ergosterol após tratamento dos parasitos com os inibidores de transporte de colesterol, demonstrado por CG/MS. A combinação de LBqT01 e cetoconazol mostrou ser mais ativa in vivo do que cada fármaco individualmente. Estudamos também o mecanismo de resistência desses inibidores, avaliando a modulação de enzimas da via de biossíntese de esteróis e a utilização de colesterol exógeno pelos parasitos. Promastigotas de Leishmania amazonensis, Leishmania braziliensis e Leishmania guyanensis foram cultivadas com concentrações crescentes de sinvastatina, terbinafina e miconazol. Estes inibidores mostraram um índice de resistência de 2,5 - 8 vezes. A resistência cruzada também foi avaliada, com estes inibidores e fármacos de referência (miltefosina, anfotericina B e antimônio trivalente)...

The trypanosomes do not synthesize cholesterol sterols but with ergostane skeleton, buta significant percentage of exogenous cholesterol is found in all species of Leishmania,suggesting a biological role for this molecule. This work aims to study the importanceof use cholesterol to Leishmania spp. in several cases, evaluating the potential of thesystem as a possible drug target. The activity of the inhibitors of ergosterol biosynthesisinhibitors associated with transport of LDL cholesterol derivative was evaluated inintracellular amastigotes and promastigotes. The association between LBqT01 andketoconazole, miconazole or terbinafine showed synergy. The association betweenimipramine or progesterone, and ketoconazole, or terbinafine indicated an additiveeffect. The ketoconazole and miconazole showed a reduction of up to twice the IC50value in amastigotes when combined with the inhibitors of cholesterol transport. Changeof ergosterol biosynthesis of parasites after treatment with inhibitors of cholesteroltransport as demonstrated by GC/MS was also observed. The combination of LBqT01and ketoconazole was more active in vivo than either drug individually. We also studiedthe mechanism of resistance of these inhibitors by evaluating the modulation ofenzymes of the sterol biosynthesis pathway and use of exogenous cholesterol byparasites. Promastigotes of Leishmania amazonensis, Leishmania braziliensis andLeishmania guyanensis were cultured with increasing concentrations of simvastatin,terbinafine and miconazole. These inhibitors showed resistance index from 2.5 to 8times. Cross-resistance was evaluated with these inhibitors and reference drugs(miltefosine, amphotericin B and trivalent antimony)...

Estudio de la composición química y actividad antifouling del extracto de la esponja marina Cliona delitrix / Study of the chemical composition and antifouling activity of the marine sponge Cliona delitrix extract

El extracto crudo y la fracción orgánica de la esponja marina Cliona delitrix, recolectada en San Andrés Islas (Caribe Colombiano), muestra actividad antifouling en ensayos de campo. La fracción orgánica es separada por cromatografía en columna logrando obtener fracciones enriquecidas en glicéridos, glicolípidos, fosfolípidos, ácidos grasos libres, ésteres metílicos y monohidroxiesteroles. Cada una de las fracciones es identificada de manera preliminar por TLC y técnicas de dereplicación (RMN). Los ácidos grasos obtenidos de la hidrólisis de cada una de las fracciones de glicéridos, glicolípidos y fosfolípidos son transformados en sus correspondientes ésteres metílicos, los cuales son analizados por CGAREM; luego se convierten en sus derivados pirrolidínicos y también se analizan por CG-EM. El estudio cuidadoso de los EM, tanto del éster metílico como de las pirrolidina, y los valores de ECL permiten identificar 89 ácidos grasos diferentes. Entre éstos se destacan: el ácido 7,10,12,14-icosatetraenoico, que se reporta por primera vez, y los ácidos 5,9-hexacosadienoico y hexadecanoico, por ser los más abundantes en todas las fracciones. Adicionalmente se identifican, mediante análisis de CG-EM y H-RMN, 19 monohidroxiesteroles. Se destacan el colestanol y el clionasterol, por ser los más abundantes, y también es de notar la presencia de estanoles (cerca del 30%) que no se habían informado antes para este género.

In a field test for antifouling activity the raw extract and the organic fraction obtained from the marine sponge Cliona delitrix, collected at the San Andrés Islas (Colombia, Caribbean Sea), showed activity. The organic fraction was separated by column chromatography to obtain enriched fractions of glycerides, glycolipids, phospholipids, free fatty acids, fatty acids methyl esters (FAMEs) and monohydroxysterols identified by TLC and dereplication techniques (NMR). The glyceride, glycolipid, and phospholipid fractions were hydrolyzed, and the fatty acids methyl esters obtained, together with the initial fatty acids fraction were converted into their methyl esters and analyzed by HRGC-MS. In order to locate unsaturations and alkyl branches in fatty acids, their methyl esters derivates were transformed to the corresponding pyrrolidides and subsequently analyzed by HRGC-MS. The identification of the fatty acids was carried out using their ECL value as methyl esters, and particularly the study of their pyrrolidide spectra was used to locate unsaturations and alkyl branch positions. The analysis allowed the identification of 89 fatty acids. The main acids include the new 7,10,12,14-icosatetraenoic acid, as well as 5,9-hexacosadienoic acid and hexadecanoic acid. Additionally, 19 monohydroxysterols were identified by HRGC-MS and NMR H. Cholestanol and clionasterol were the most abundant compounds and the stanols presence (near to 30%) was not previously reported for this genus.

Avaliação da utilização de colesterol exógeno por Leishmania amazonensis como possível alvo farmacológico / Evaluation of the use of exogenous cholesterol by Leishmania amazonensis as possible pharmacological target

Todos os fármacos atualmente em uso para o tratamento da leishmaniose apresentam restrições, como toxicidade, graves efeitos colaterais, custo elevado, administração parenteral ou teratogenicidade. Desta forma, o desenvolvimento de fármacos mais eficazes e seletivos é de suma importância e a identificação de vias metabólicas exclusivas do parasito que possam ser usadas como alvo pode ser um ponto de partida interessante. Acredita-se que a leishmania não dependa da utilização do colesterol exógeno para sua sobrevivência, uma vez que sintetiza seus próprios esteróis. Porém, apesar disso, um percentual expressivo de colesterol é encontrado em suas membranas sendo, em alguns casos, o esterol majoritário indicando um papel biológico para essa molécula. O presente trabalho visa estudar a importância para a L. amazonensis da utilização do colesterol proveniente do soro, em diversas situações, avaliando o potencial desse sistema como um possível alvo farmacológico. A atividade dos inibidores da biossíntese do ergosterol (cetoconazol, miconazol, terbinafina e sinvastatina) foi avaliada, na presença de soro normal ou deslipidado. Foi observada que a privação das lipoproteínas do soro potencializa o efeito dos inibidores do ergosterol. Os promastigotas tratados com esses inibidores mostraram diferenças na sua composição lipídica, com acúmulo de colesterol nas células tratadas, principalmente, com cetoconazol e miconazol, indicando um possível mecanismo de compensação da leishmania, para suprir a inibição do ergosterol. Experimentos com LDL-I125, no qual tanto a leishmania tratada com cetoconazol, quanto a tratada com sinvastatina, que inibe o início da via de biossíntese de ergosterol, aumentaram a captação da LDL. A suramina, um inibidor da captação de LDL, mostrou uma diminuição do conteúdo de colesterol da leishmania e, em associação com a sinvastatina, obteve um efeito sinérgico, mostrando que o conteúdo da LDL, principalmente colesterol, pode estar envolvido na manutenção da integridade da membrana da célula. Em adição, a resistência ao cetoconazol induzida in vitro foi estudada. Foi observada uma relação direta entre o aumento da expressão gênica da C14-desmetilase com o nível de resistência induzido em promastigotas de L. amazonensis, sugerindo que esse seja o principal mecanismo de resistência a essa classe de fármacos. De uma maneira geral, a análise dos resultados como um todo sugere que o colesterol desempenhe um importante papel na atividade dos inibidores da biossíntese do ergosterol e que o bloqueio da sua utilização pode ser um possível alvo farmacológico.

Caracterização de microdomínios da membrana resistentes a detergentes não-iônico em promastigotas de Leishmania (Viannia) braziliensis: papel dos microdomínios na infectividade / Characterization of non-ionic detergent resistant membrane microdomains in Leishmania (Viannia)braziliensis promastigote: role of microdmains in the infectivity

A elucidação estrutural de glicoconjugados de superfície de Leishmania é um tema de grande relevância uma vez que estes componentes mostram-se envolvidos em diversos processos na interação do parasita com a célula hospedeira. Desse modo, seis frações glicolipídicas, denominadas de B1 a B6, foram purificadas de promastigotas de L. (v. ) braziliensis por cromatografia líquida de alta resolução (HPLC) . Todas as frações foram lábeis à hidrólise alcalina suave e as análises por cromatografia gasosa acoplada a espectrometria de massa (GC/MS) demonstraram a presença de manose, galactose, glucose, glucosamina e myo-inositol, sugerindo que os glicolipídeos sejam glicoinositolfosfolipídeos (GIPLs) . A análise dos alditóis acetato parcialmente metilados (PMAAs) mostrou a presença de 2,4 -di -O-metil-mani tol tetracetato, sugerindo uma estrutura glicana ramificada contendo resíduo de galactose terminal, decorrente da presença de 2,3,4,6-tetra-O-metil galactitol diacetato entre os PMAAs . A reatividade com o anticorpo monoclonal (mAb) 8T-3 também sugere a presença de resíduos de Galb1-+3Galcx na porção glicana dos GIPLs. Estes resultados indicam que promastigotas de L. (v. ) braziliensis expressam GIPLs, os quais possivelmente possam ser incluídos nos GIPLs tipo híbrido apresentando, entretanto, novas estruturas glicanas...

Caracterização físico-química de creme vegetal enriquecido com ésteres de fitosteróis / Physico-chemical characterization of a phytosterol ester enriched margarine

Atualmente, esteróis e estanóis têm sido adicionados a margarinas especiais, comercialmente disponíveis como alimentos funcionais, com o intuito de reduzir os níveis de colesterol. Como parte de uma dieta saudável, é cientificamente comprovado que esse tipo de produto reduz o colesterol LDL em aproximadamente 10-15 por cento. A literatura disponível sobre os efeitos dos fitosteróis/fitostanóis na redução do colesterol no organismo, bem como a forma como estes componentes são metabolizados, é muito vasta. Porém, informações sobre as propriedades físicas e químicas destas substâncias e os efeitos de sua aplicação em alimentos, do ponto de vista tecnológico, dificilmente são encontradas...

Relación entre acumulación de rodamina 6G y resistencia a fluconazol en Saccharomyces cerevisiae S288c / Relationship between rhodamine 6G accumulation and fluconazole resistance in Saccharomyces cerevisiae S288c

Severe mycotic infections are a source of concern in immunocompromised patients or in those who receive chemotherapy for hematological malignant diseases. One of the causes is referred to the appearance of antimycotic resistant microorganisms. Fluconazole is one of the antimycotic used for invasive mycoses treatment. Therefore it is necessary to evaluate the factors that originate this resistance. In the present report the yeast Saccharomyces cerevisiae S288c was used as a model system. In resistant strains the accumulation of the lipophilic cation Rhodamine 6G, L-leucine uptake and growth inhibition by crystal violet dye were determined. The results presented herein demonstrate the correlation between the membrane potential and the resistance to fluconazole presented by S. cerevisiae strain S288c.

Partial chemical characterization of antigenic preparations of chromoblastomycosis agents

Antigenic preparations (saline, methylic, metabolic and exoantigens) of four agents of chromoblastomycosis, Fonsecaea pedrosoi, Phialophora verrucosa, Cladophialophora (Cladosporium) carrionii and Rhinocladiella aquaspersa were obtained. Partial chemical characterization of these antigenic preparations was obtained by determination of the levels of total lipids, protein, and carbohydrates, and identification of the main sterols and carbohydrates. Methylic antigens presented the highest lipid contents, whereas metabolic antigens showed the highest carbohydrate content. Total lipid, protein, and carbohydrate levels were in the range of 2.33 to 2.00 mg/ml, 0.04 to 0.02 mg/ml and 0.10 to 0.02 mg/ml, respectively, in the methylic antigens and in the range of 0. 53 to 0.18 mg/ml, 0.44 to 0.26 mg/ml, and 1.82 to 1.02 mg/ml, respectively, in saline antigens. Total lipid, protein, and carbohydrate contents were in the range of 0.55 to 0.20 mg/ml, 0.69 to 0.57 mg/ml and 10.73 to 5.93 mg/ml, respectively, in the metabolic antigens, and in the range of 0.55 to 0.15 mg/ml, 0.62 to 0.20 mg/ml and 3.55 to 0.42 mg/ml, respectively, in the exoantigens. Phospholipids were not detected in the preparations. Saline and metabolic antigens and exoantigens presented hexose and the methylic antigen revealed additional pentose units in their composition. The UV light absorption spectra of the sterols revealed squalene and an ergosterol fraction in the antigens. The characterization of these antigenic preparations may be useful for serological evaluation of patients of chromoblastomycosis.

Fatty Acid and Sterol Composition of Three Phytomonas Species

Fatty acid and sterol analysis were performed on Phytomonas serpens and Phytomonas sp. grown in chemically defined and complex medium, and P. françai cultivated in complex medium. The three species of the genus Phytomonas had qualitatively identical fatty acid patterns. Oleic, linoleic, and linolenic were the major unsaturated fatty acids. Miristic and stearic were the major saturated fatty acids. Ergosterol was the only sterol isolated from Phytmonas sp. and P. serpens grown in a sterol-free medium, indicating that it was synthesized de novo. When P. françai that does not grow in defined medium was cultivated in a complex medium, cholesterol was the only sterol detected. The fatty acids and sterol isolated from Phytomonas sp. and P. serpens grown in a chemically defined lipid-free medium indicated that they were able to biosynthesize fatty acids and ergosterol from acetate or from acetate precursors such as glucose or threonine

Valor de los niveles basales de gonadotropinas para predecir la respuesta folicular en ciclos de FIV-TE y GIFT / Baseline values of gonadotrophins for predecting follicle response in FIVTE and GIFT cycles

El objetivo del trabajo es determinar el valor predictivo que pueden tener los nivles séricos basales de gonadotropinas hipofisiarias en relación a la respuesta folicular a esquemas de estimulación folicular múltiple en un programa de reproducción asistida. Se estudiaron 35 paciente tratadas con FSH pura y mentropinas, haciéndose la monitorización de la respuesta mediante determinación sérica de estradiol y medición ultrasonográfica vaginal de los diámetros foliculares a partir del día 8 del ciclo. Las cuantificaiones basales de gonodotropinas hispofisiarias y estradiol se realizaron en el día 3 del ciclo de tratamiento. En función de la respuesta folicular se formaron 2 grupos y en cambio las diferencias en los niveles basales de FSH y de LH fueron notorias y estadísticamente significativas llegándose a la conclusión de que los niveles basales de las hormonas gonadotrópicas hipofisiarias tomadas en el día 3 del ciclo, predicen sensiblemente la cálidad de la respuesta folicular distinguiéndose dos patrones diferentes.

Contenido de colesterol y otros esteroles en alimentos chilenos / Cholesterol and other sterols content in chilean food

Se determinó colesterol y esteroles vegetales en diversos alimentos de consumo frecuente en nuestro país. Entre los alimentos analizados se encuentran vísceras, yemas de huevo, alimentos grasos tanto de origen vegetal como animal, algunas especies de pescados y mariscos y ocho raciones consideradas de alto consumo en Chile. Las muestras fueron adquiridas en locales comerciales ubicados en diversos lugares de Santiago, excepto algunas de las muestras de raciones que fueron proporcionadas por particulares. De los resultados obtenidos se puede concluir que los alimentos con más alto contenido de colesterol son las vísceras, en especial los sesos, con un promedio de 2.420 mg. y la yema de huevo, con un promedio de 1.118 mg. por 100 g entre los alimentos grasos, las margarinas de origen animal y/o marino presentaron valores del mismo orden de colesterol que la mantequilla, alrededor de 200 mg de colesterol por 100 g de producto. De los productos marinos las gónadas de erizo fueron las que presentaron el más alto contenido en colesterol, los otros pescados y mariscos presentaron valores más bajos. De las ocho raciones estudiadas sólo aquellas que incluyeron huevo en su preparación presentaron un alto contenido de colesterol por ración que sobrepasa las recomendaciones de ingesta diaria de 300 mg. En los aceites vegetales se cuantificaron los fitoesteroles presentes, siendo el más importante el betasitoesterol.

Investigación de Esteroles en productos lácteos por cromatografia de gases / Study of sterols in dairy products for gas chromatography

Se describe un nuevo método de análisis cualitativo para detectar la presencia de colesterol y de grasas vegetales en la mantequila y en otros productos lácteos, basado en la parte insaponificable de los ésteres glicéridos constituyentes de la grasa láctea, con el objeto de separar la parte insaponificable (la cuál esta constituida por los esteroides: colesterol, sitosterol, etc.), de la parte saponificable. La saponificación es seguida de la extracción con el solvente adecuado, para la posterior identificación de los compuestos señalados