Não consta resumo na publicação. / Abstract not available.

As the battle against ever-increasing drug resistence bacteria rages on, novel and sometimes more complex natural products can be used to combat this. In this study, two-dimensional NMR techniques were utilized to collect a complete spectral data set for two natural products. The first structure, a synthesized Pyrrolobenzodiazepine alkaloid natural product was confirmed through these methods. The second, a strain of Rhodococcus, MTM3W5.2, produces a novel antibacterial molecule in broth cultures and the active compound was fractionated using a Sephedex LH-20 column. Chromatographic purification yielded a pure sample at 58.90 minutes, RT.58. HRMS data deduced an exact mass of 911.5490 Da, equivalent to a molecular formula of C52H78O13. Several major spin systems were constructed from the 2D-NMR spectra. However, due to limited sample quantity in compound with a large molecular weight and product instability, the long range HMBC signals needed to connect these fragments have not yet been obtained.

No description available.

No description available.

The use of traditional medicine through the use of medicinal plants in Africa and especially in South Africa has long been considered an important characteristic of people's daily lives and socio-cultural heritage. Cotyledon Orbiculata is among the medicinal plants that are used by South African traditional practitioners for the treatment of epilepsy and painful conditions such as corns, warts, toothache, earache, boils and various other ailments. However, the claim of therapeutic successes of medicinal plants by traditional medicine practitioners are hardly subjected to scientific scrutiny. This study therefore, investigated the anti-epileptic property of Cotyledon Orbiculata by studying the effects of the methanol extract of the plant against chemically induced seizures by pentylenetetrazole, picrotoxin, bicuculline and N-methyl-DL-aspartic acid in mice. The study also investigated the analgestic effects of Cotyledon Orbiculata by studying the effect of the plant extract on pain induced by acetic acid and hot plate thermal stimulation.

Medicinal bulbs form part of the diversified flora in South Africa. The plants are used extensively in South African traditional medicine in the treatment of various ailments. Due to the ever-increasing demand and the unrestricted collection of medicinal plants from the wild, many of these slow growing bulbous plant species are driven into over-exploitation and extinction. The main parts collected for use are the underground bulbs, leading to the destructive harvesting of the whole plant. This form of plant harvesting poses threats to the long term sustainability of these plant resources from their natural habitats. Sustainable harvesting of these plants should be within the limits of their capacity for self-renewal. However, this seldom occurs with the often inconsiderate medicinal plant gatherers. Conservation of these plants is therefore necessary. A strategy that would take into consideration the sustainable harvesting and perhaps simultaneously provide similar medicinal benefits, would be the substitution of bulbs with leaves of the same plant. This study was aimed at evaluating the seasonal pharmacological and phytochemical properties in bulbs/corms and leaves of medicinal bulbs with a view of promoting the substitution of bulbs with leaves in traditional medicinal use. Four medicinal bulbous plants, Tulbaghia violacea, Hypoxis hemerocallidea, Drimia robusta and Merwilla plumbea were evaluated for the pharmacological and phytochemical properties in their bulbs/corms and leaves in spring, summer, autumn and winter seasons, with a view of promoting the use of leaves as a conservation strategy. Dried plant materials were sequentially extracted with petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water in each season. The extracts were tested for activities against Gram-positive (Bacillus subtilis and Staphylococcus aureus), Gram-negative (Escherichia coli and Klebsiella pneumoniae) bacteria and the fungus Candida albicans using the in vitro microdilution assays to obtain minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC). The four plant species were also evaluated for their ability to inhibit cyclooxygenase (COX-1 and COX-2) enzymes. Spectrophotometric methods were used to evaluate saponin and phenolic contents of samples from the four plant species in each season. Antibacterial activity was fairly comparable between bulbs/corms and leaves of H. hemerocallidea, T. violacea, and M. plumbea, with at least one extract showing some good activity (MIC < 1 mg/ml) in most of the seasons. Bulb extracts of D. robusta did not show good antibacterial activity while the leaf extracts showed good activity (0.78 mg/ml) against B. subtilis in spring, summer, and autumn and S. aureus (0.78 mg/ml) in autumn. The best antibacterial activity was recorded in winter, with MIC values as low as 0.195 mg/ml from the DCM bulb extracts of T. violacea against K. pneumoniae and S. aureus and PE corm extracts of H. hemerocallidea (0.195 mg/ml) against B. subtilis. Good antibacterial activity from water extracts were only recorded from corm extracts of H. hemerocallidea in summer, autumn and winter, H. hemerocallidea leaf extracts in autumn and winter, and M. plumbea bulb extracts in autumn. The leaf extracts of all the screened plant species demonstrated good fungicidal activity in autumn, with H. hemerocallidea corm water extracts recording an MFC value as low as 0.39 mg/ml. The leaf extracts of H. hemerocallidea (water), D. robusta (DCM) and M. plumbea (DCM) had good MFC values of 0.78 mg/ml each, in spring. The DCM leaf extracts of T. violacea also showed good fungicidal activity (0.78 mg/ml) in summer, while corm water extracts of H. hemerocallidea had an MFC value of 0.39 mg/ml in winter. There were no fungicidal activities recorded from all the bulb extracts in all the seasons. All the PE and DCM extracts in all the tested plant samples recorded between moderate (40-70%) and high (> 70%) COX-1 and COX-2 inhibition levels across all seasons. The EtOH corm extracts of H. hemerocallidea also demonstrated moderate to high inhibitory activity against COX-1 enzyme across all seasons. Bulb and leaf extracts of T. violacea showed selective inhibitory activity for COX-2 enzyme in all the seasons. The highest COX inhibitory levels were recorded in COX-2 from the PE leaf (spring) and bulb (autumn) extracts of T. violacea, with both recording 100% inhibitory activity. Phytochemical analysis revealed higher total phenolic compounds in bulbs/corms and leaves of all the analysed plant species, to be either higher in spring or winter. Plant material collected in autumn had the least levels of total phenolics. An almost similar trend to that of total phenolics was observed for flavonoids, gallotannins and condensed tannins in most plant samples, with higher levels either in spring or winter. Total saponins were consistently higher in winter than in the other seasons in all the screened plant species. There were in some cases, relationships between the peaks in the levels of some phytochemical compounds and the observed levels of bioactivity in different assays. The results obtained from this study demonstrate that the leaves of the screened plant species may substitute or complement bulbs in the treatment of certain ailments in traditional medicine. Thus, plant part substitution can be sustainably utilised in the conservation of these plant species while retaining the same medicinal benefits. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

The use of traditional medicine is a popular practice in South Africa especially among rural dwellers due to several reasons such as availability of natural products, cultural beliefs, preference of natural products to synthetically derived drugs and the high cost of modern drugs. Traditional healers in South Africa play key roles in administering treatment for all sorts of ailments using plants. The aim of this study was to evaluate the efficacy of seven selected medicinal plants that are used in traditional medicine to treat stomach-related ailments for their pharmacological and phytochemical properties. Plant material was extracted sequentially with ethyl acetate (EtOAc), ethanol (EtOH) and water. The extracts were evaluated for their antimicrobial activities using the microdilution technique against two Gram-positive (Enterococcus faecalis ATCC 19433 and Staphylococcus aureus ATCC 12600) bacteria and a Gram-negative (Escherichia coli ATCC 11775) bacterium. A modified microdilution technique was used to screen for antifungal activity against a yeast-like fungus (Candida albicans ATCC 10231). Only the EtOAc extract of Tetradenia riparia demonstrated good antibacterial activity against the Gram-negative E. coli, all the other extracts that were active only showed good antibacterial activity against the two Gram-positive (E. faecalis and S. aureus) bacteria with MIC values <1 mg/ml. None of the extracts that exhibited good inhibitory activity showed corresponding bactericidal activity against the bacterial test strains, suggesting that the observed activity were all inhibitory. Good antifungal activity with an MIC value <1 mg/ml was observed in only 5 extracts, and none of the extracts exhibited corresponding fungicidal activity. The in vitro colorimetric assay for anthelmintic activity against Caenorhabditis elegans revealed that almost all the extracts possessed moderate to high anthelmintic properties. The EtOAc extract of T. riparia had the best activity at MLC value of 0.004 mg/ml. The anti-inflammatory activity of the plant extracts was tested using the cyclooxygenase assays to determine their inhibitory potential against COX-1 and COX-2 enzymes. All the EtOAc extracts demonstrated both COX-1 and COX-2 inhibitory activity in the range of 50.7 ± 2.4 to 99.5 ± 0.5%. Apart from the EtOH extracts of C. multicava that showed high inhibitory activity against both COX-1 and COX-2, all the other EtOH extracts were COX-2 selective. Aqueous extracts exhibited poor inhibitory activity against both COX-1 and COX-2 enzymes with the exception of T. riparia and Coddia rudis that showed good inhibitory activity (69.1 ± 0.9 and 92.65 ± 0.7%) against COX-1 and COX-2 respectively. The standard plate incorporation assay for the Ames test was carried out to determine the potential genotoxic effects of the plant extracts and this revealed that all the extracts were non-mutagenic towards Salmonella typhimurium tester strains TA98, TA100 and TA1537 without metabolic activation. However, further studies incorporating metabolizing enzymes are needed to confirm the safe use of the studied plants. Phytochemical analysis revealed relatively high amounts of total phenolics, gallotannins and flavonoids in all the evaluated plants. Total and steroidal saponins were detected in only two plant samples, Canthium spinosum and Cassinopsis ilicifolia (bark). These findings present useful information on the types of bioactive compounds that could be responsible for the pharmacological activities observed among some of the plant extracts. The results obtained in this study showed different levels of pharmacological activities among all the evaluated medicinal plants which provide scientific validation for their use in traditional medicine as antimicrobial agents. Phytochemical analysis provides valuable information for further study that will be aimed at isolation and identification of the bioactive principles in the evaluated plant species. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Philodendron bipinnatifidum Schott é populannente conhecida como cipó-imbé, filodendro, imbé, guaimbé, banana-de-macaco, costela-de-Adão, entre outras denominações populares. Apesar de ser reconhecida como planta tóxica por muitos, existem relatos de sua utilização em erisipela, inflamações reumáticas, orquite; as folhas são aplicadas sobre úlceras. A raiz em pó é conhecida como purgativo drástico. Para as análises anatômicas foram utilizadas as partes aéreas floridas e as raízes aéreas de plantas adultas. A raiz aérea escora apresenta duetos secretores (resiníferos) de origem esquizógena, cilindro vascular lobado, laticíferos entre cordões de floema de tamanho conspícuo Na lâmina foliar, as epidermes em vista frontal apresentam cutícula espessa sem ornamentações, na face adaxial as células epidérmicas possuem paredes retas com ausência total de tricomas e estômatos. Na face abaxial as células são de contorno levemente sinuoso e ocorrem estômatos do tipo paracítico. O parênquima esponjoso mostra uma organização colunar das células do mesofilo e no meio deste, ocorrem grandes idioblastos contendo ráfides. No pedalo, como na nervura central e no caule, existem grandes cavidades de ar alongadas longitudinalmente, delimitadas por uma camada de células, entre as quais ocorrem idioblastos contendo ráfides que se projetam para o interior das mesmas. A triagem química revelou a presença de flavonóides, mucilagens, compostos esteroidais, alcalóides, saponinas (4,52% e 2,52%, para órgãos aéreos e raízes aéreas escoras, respectivamente) e taninos (5,46% e 21,13%, para órgãos aéreos e raízes aéreas escoras, respectivamente). O extrato fluido e a fração hidroalcoólica 50% foram ensaiadas através de indução aguda de úlcera por etanol e ácido clorídrico. Os resultados foram significativos apenas no nível de ulceração IH. Foi realizado teste de toxicidade aguda com os extratos fluidos liofilizados de órgãos aéreos e raízes aéreas escoras de P. bipinnatifidum Schott em dose única de 5000 mglkg, por via oral, em camundongos Swiss, machos e fêmeas, observados por um período de 14 dias. O ensaio de toxicidade subcrônica do extrato fluido liofilizado de raízes aéreas escoras foi realizado em dose diária de 800 mg/kg, por via oral, durante 38 dias consecutivos. Os resultados analisados em função da variação do peso dos animais, do consumo de água e ração e do peso relativo do baço, figado, rins e pulmões, não foi significativo, ou seja, nas condições experimentais não houve variação em relação ao controle. A atividade antiinflamatória foi avaliada, sendo os modelos utilizados: edema de pata induzido pela carragenina e dermatite induzida pelo óleo de cróton, no entanto, não foram obtidos resultados significativos. Os extratos liofilizados de órgãos aéreos e raízes aéreas escoras não apresentaram atividade antimicrobiana. / Philodendron bipinnatifidum Schott is populary known as Cipo-imbé, Filodendro, Imbé, Guaimbé, Banana-de-macaco, Costela-de-Adão, Bananeira do brejo. Nevertheless it is recognized as a toxic plant, there are reports about utilization in erysipela, rheumatic inflammations, orchits; the leaves are applied on ulcers. The powdered root is a drastic purgative. Aerial parts and aerial roots have been employed for the anatomic analyses. Phytochemical screening showed the presence of flavonoids, steroids, saponins, alkaloids, essential oilJs and mucilages. The crude extract and the 50% hydroalcoholic fraction were tested against ulcer through acute induction by ethanol and hydrochloric acid. Results were significant only at level mulceration. The acute toxicity was tested with the dose of 5000mg/kg, and the subchronic toxicity, with 800 mg/kg, of the crude extract, orally administred, and the subchronic toxicity was performed during 38 days. The weight variation ofthe animals, food and water consumption and the relative weight of the spleen, liver, kidneys and lungs, were not significant. The results of the antiinflammatory test were not significant.

Croton urucurana Baillon, comumente conhecida como \"sangra-d\'água\", é uma árvore medicinal do suldeste brasileiro utilizada como cicatrizante e antiinflamatório. A espécie carece de estudos botânicos, químicos e farmacológicos para que possa ser utilizada com segurança. O objetivo deste trabalho foi caracterizar a casca, a folha e o látex obtidos desta espécie, através de estudos farmacognósticos, isolando princípios ativos e verificando a toxicidade e as atividades antiúlcera e cicatrizante. Dentre as principais características macroscópicas podemos citar: (a) casca; enrolada com presença de manhas brancas, fratura fibrosa e sabor adstringente; (b) folha; simples, pubescente, cordiforme, peninérvea e ápice agudo. Quanto as características microscópicas temos: (a) casca; floema, pseudocórtex e periderme apresentado drusas, cristais prismáticos e amiloplastos; grande quantidade de esclereídes, células com taninos e laticíferos não articulados; (b) folha; mesofilo assimétrico com presença de grandes drusas; epiderme com pêlos estelares e estômas paracíticos. Na triagem fitoquímica foram encontrados alcalóides, esteróides, compostos fenólicos, taninos, saponinas e óleo essencial. O teor de taninos presente no látex é de 1,02%, determinado por gravimetria. Foram realizadas determinações físico-químicas (segundo Farmacopéia Brasileira) e cromatográficas das drogas (casca e folha) e de seus extratos. A taspina, um alcalóide cicatrizante, foi isolado do látex e identificado por I.V. e RM.N. O látex é altamente tóxico por via oral, e apresenta atividade cicatrizante e antiúlcera, verificado por ensaios com ratos Wistar. / Croton urucurana Baillon, commonly known as \"sangra-d\'água\", is a medicinal tree a southest brazilian, used for healing of wounds and antiinflammatory. There are not data about the botanical, chemical and pharmacological studies for the drug to used with safety. The objective of our search to was characterize to bark, the leaf and the latex obtained from this species, through pharmagnostics studies, active principle isolation and its toxicity, antiulcer and wound healing activities. the main macroscopic characteristics are: (a) bark, rolled up with presence of white spots, its fractures is fibrous and flavor astringent; (b) leaf; simple, puberulent, cordate, pinnately veined and acute apice. The microscopic characteristics have: (a) bark; phoem, pseudocortex and periderm with druses, prismatic crystals and starch; great amount of sclereids, cells with phenolic content and non-articulate laticifers; (b) leaf; asymmetric mesophyll with enormous druses of calcium oxalate, abundant in the palisade parenchyma; epidermis with stellate hairs and stomata paracytic. In the phytochemical screening there were detected alkaloids, steroids, phenolics compounds, tannins, saponins and essential Gil. The proportion of tannins presents in the latex is of 1,02%. The physical-chemical and chromatographic profiles (according to Farmacopéia Brasileira) of the drugs (bark and leaf) and of its extracts were determined. The taspine, a wound healing alkaloid, was isolated of the latex and identified by I.R. and M.N.R. The látex showed to be highly toxicant and to have a wound healing and antiulcer activity, assayed in Wistar rats.

O jambeiro (Syzygium jambos (L.) Alston) constitui uma das diversas espécies frutíferas e medicinais pertencentes à família Myrtaceae. Popularmente, são atribuídas ao jambo propriedades antidiabética, antitussígena e contra dores de cabeça. A caracterização farmacobotânica da droga constituída de folhas foi realizada através de análise macro e microscópica, buscando características peculiares com objetivo de contribuir na identificação da droga vegetal. A triagem fitoquímica da droga indicou a presença de flavonóides, taninos e óleo volátil. O extrato hidroetanólico a 70%, obtido através de percolação, foi concentrado e liofilizado. O teor de taninos verificado na droga e no extrato foi de 21,9% e 43,3%, respectivamente. A droga apresentou 0,6% de flavonóides totais e o extrato, 1,2%. O extrato foi fracionado por solventes de polaridades diferentes (clorofórmio, acetato de etila, etanol e etanol a 50%). O perfil cromatográfico foi determinado para o extrato e frações. A toxicidade aguda foi avaliada através da administração oral do extrato a camundongos, em dose única de 5 g/kg. Como houve mortes, foi determinada a DL50 através da administração de 5 doses crescentes de extrato. O valor de DL50 encontrado foi de 4,68 g/kg. A atividade antimicrobiana do extrato foi avaliada através da determinação de concentração mínima inibitória (CMI) pelo método de diluição em meio líquido em tubos. Os microrganismos utilizados foram S. aureus, E. coli, A. niger e C. albicans. O extrato mostrou-se eficaz apenas contra S. aureus, apresentando CMI entre 200 e 300 &#181;g/mL. A avaliação da atividade antiúlcera do extrato e das frações foi realizada através de indução aguda por etanol acidificado. O extrato, administrado na dose de 400 mg/kg, apresentou resultados extremamente significativos nas ulcerações de nível III (hemorrágicas). As frações etanólica e clorofórmica mostraram-se efetivas nas ulcerações de nível II e III. A atividade antioxidante foi testada através da medida da velocidade de produção de malonildialdeído na lipoperoxidação espontânea de homogenato de cérebro de ratos. O extrato de S. jambos apresentou Q1/2=0,165 &#181;g/mL. / Syzygium jambos (L.) Alston, Myrtaceae, is commonly employed in folk medicine to treat diabetes, cough and headaches. Dried leaves were morphologic and anatomically studied. Phytochemical screening of the powdered dried leaves indicates the presence of flavonoids, tannins and essential Gil. Hydroethanolic extracts (70%) were prepared by percolation and freeze-drying. The tannin content of dried leaves and extract was, respectively, 21,9% and 43,3%. The flavanoid content was 0,6% (dried leaves) and 1,2% (extract). Acute toxicity studies were performed afier oral administration of the leaf extract to mice, at a dose of 5 g/kg. The LD50 value for the extract (oral administration of five different doses) was 4,68 g/kg. The dilution method was used to determine the minimum inhibitory concentration (MIC) of S. jambos extract against Staphylococcus aureus strain ATCC 6538, Escherichia coli strain ATCC 10536, Candida albicans strain ATCC 10231, Aspergillus niger strain ATCC 16404. Hydroethanolic extract of leaves of S. jambos inhibited the growth of S. aureus (200 < MIC < 300 &#181;g/mL), but had no activity against E. coli, A. niger and C. albicans at 1000 &#181;g/mL. Previous oral administration of S. jambos extract (400 mg/kg) reduced significantly gastric injury induced by HCl/ethanol. In vitro antioxidant activity of S. jambos extract was evaluated by malondialdehyde (MOA) measure in a method based on the inhibition of spontaneous lipid peroxidation of brain homogenates. The Q1/2 value for the extract was 0,165&#181;g/mL.