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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Caracterização química e biológica de espécies do gênero Brunfelsia L. (Solanaceae) nativas do Rio Grande do Sul

Schneider, Ana Leticia Stedelle 13 March 2015 (has links)
No description available.
92

A biochemical study of the antidiabetic and anticogulant effects of Tulbaghia Violacea

Davison, Candice January 2010 (has links)
Secondary metabolites derived from plants, especially those used by traditional healers, are at the forefront of new drug development in combating diseases such as cancer and diabetes. Garlic is employed in indigenous medicine all over the world for the treatment of a variety of diseases. Dietary garlic has been recognized for its beneficial health effects. In particular, garlic consumption has been correlated with (i) reduction of risk factors for cardiovascular diseases and cancer, (ii) stimulation of immune function, (iii) enhanced detoxification of foreign compounds, (iv) hepatoprotection, (v) antimicrobial effects, (vi) antioxidant effects, and most importantly (vii) its hypoglycemic and anticoagulant properties. Due to these beneficial properties, garlic and its closely related genera which includes Tulbaghia violacea, may be useful as coadjuvant therapy in the treatment of type 2 diabetes and some of its physiological complications. The aim of this study was to determine if T. violacea has antidiabetic and anticoagulant properties. This was performed in vitro using both aqueous and organic extracts of the roots, leaves and bulbs. An organic extract was able to improve glucose-stimulated insulin secretion (GSIS) in INS-1 pancreatic β-cells and glucose uptake in Chang liver cells. The BO extract had no effect on the glucose uptake in 3T3-L1 an adipose cell line and reduced glucose utilisation in C2C12, a skeletal muscle cell line. Some of the properties displayed by T. violacea in this study are consistent with those found in similar studies with garlic extracts. It was observed that the BO extract increased the membrane potential and Glut-2 expression in INS-1 cells cultured at hyperglycemic levels, however, at normoglycemic levels a reduction was observed. The oxygen consumption increased at both glycemic levels due to treatment with the BO extract. Platelets were exposed to the extracts to determine their effects upon platelet aggregation, adhesion and protein secretion. Since the BO extract displayed the highest potential at inhibiting platelet aggregation and adhesion. A rat model was used in ex vivo studies to determine if the extract exhibited the same effect in a physiological model. It was noted that the BO extract exhibited a higher degree of inhibition on platelet aggregation and adhesion than the positive control, aspirin. The BO extract reduced clotting times in the prothrombin time (PT) test, but prolonged the clotting time in the actived partial thromboplastin time (APTT) assay in the ex vivo model; however, it had no affect on these clotting assays in the in vitro model using human blood. The BO extract increased the D-dimer and Fibrinogen-C levels in the in vitro model, but had no effect on the D-dimer concentrations and lowered the Fibrinogen-C levels in the ex vivo model. The active compounds in the extract remain to be elucidated.
93

The therapeutic value of Aloe Ferox Mill

Mhaladi, Refilwe January 2014 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, 2014 / The rising costs of health care, the outbreak of drug resistant organisms, health depleting lifestyles and the risky side effects of currently used drugs are world-wide problems. This has led to the search for novel drugs and drug leads. Traditional healers and other individuals across the globe possess unlimited knowledge on the healing powers of different plants that has been passed on through generations. This knowledge together with scientific investigations can lead to the eradication of most of the diseases either by treatment or prevention. Aloe ferox Mill. is one of the plants that have gained a lot of interest from the pharmaceutical industry. The plant has over 80 documented medicinal uses. These include treatment of impotence and infertility, sexually transmitted infections, arthritis, hypertension, leukaemia, bacterial and fungal infections. It is also known as a blood purifier, widely used as a laxative and anti- inflammatory agent. More research is required to discover more about A. ferox and its benefits to health as well as to investigate its potential for the development of novel drugs. The current study was focused at investigating the anti- cancer, anti- microbial antidiabetic, cytotoxic activities and phytochemical composition of leaf extracts of A. ferox. Three cancer cell lines namely: breast (MCF7), colon (HCT116) and prostate (PC3) cancer cell lines were used to investigate the anticancer activity of the extracts using the Sulforhodamine B (SRB) method. To determine the anti- diabetic activity of the plant extracts the C2C12 and Chang cell in- vitro models of glucose uptake were used. The micro- dilution technique was IV used to evaluate the antibacterial and antifungal activity of the extract. The safety of these extracts against normal human foetal lung fibroblasts (W138), Chang and C2C12 cells was done by through the SRB and the MTT methods. To determine the phytochemical profile of A. ferox the DPPH radical scavenging and the Folin Ciocalteu methods were used to test the antioxidant activity and the total phenolic content of the different extracts respectively. Different methods were used to determine the presence of phytochemicals such as steroids, saponins, alkaloids, carbohydrates and flavonoids. LCMS was also done to detect the elemental composition of the plant extracts. According to the CSIR criteria A. ferox was inactive against the cancer cell lines used. It however exhibited antioxidant activity even at low concentrations, with an EC50 of 0.865 ± 0.783. The methanol extract showed more phenolic content than the dichloromethane and aqueous extracts at a concentration of 5mg/ml. It is believed that the antioxidant activity correlates with the phenolic content and quality of the phenols present in the plant and more assays have to be done to prove this hypothesis. Other phytochemicals found in the extract included saponins, steroids, alkaloids as well as flavonoids. Both the methanol and aqueous extracts of A. ferox caused a significant increase in glucose uptake by C2C12 cells but caused a slightly decreased uptake by the Chang cells. The plant extracts inhibited the growth of Staphylococcus epidermidis, Streptococcus pneumonia, Escherichia coli and Candida albicans at a concentration of 15mg/ml extract. Candida tropicalis and Escherichia faecalis were resistant to A. ferox extracts. Finally the extracts showed no toxic activity against the normal foetal lung fibroblasts, Chang and C2C12 cells validating the safety of this plant for human use. V The results in conjunction with literature findings show A. ferox to be a promising source of drugs and therapeutic agents. Due to the fact that traditional healers already rely on it as treatment for different ailments, it is important that the safety of the plant for use has been validated though other studies and clinical trial still need to be done to fully confirm this. All the information gathered also showed this plant to be of great benefit against major health problems, responsible for millions of deaths each year such as cancer, cardiovascular and inflammatory diseases, and diabetes. There is however still a great need for more investigation to be done on this plant against a vast majority of organisms and diseases so as to fully benefit from it.
94

HPLC-MS analysis of radix astragali, cortex phellodendri, rhizoma coptidis and sanhuang xiexin decoction /cTsai, Sam Hip. / CUHK electronic theses & dissertations collection

January 2007 (has links)
A method is presented for the simultaneous identification of nine compounds in samples of A. membranaceus and A. membranaceus var. mongholicus. Compounds identified in the extracts of the two plants included glycosides, saponins and flavonoids. They are identified as Calycosin-7-O-beta-D-glucoside (C1), Ononin (C2), (6aR,11aR)-3-hydroxy- 9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (C3), (3R)-7,2'-dihydr- oxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside (C4), Calycosin (C6), Astragaloside IV (C5 ), Formononetin (C7), (6aR,11a R)-3-hydroxy-9,10-di-methoxypterocarpan (C8), and Isomucronulatol (C9). / An HPLC-DAD-MS method is proposed for the differentiation of Rhizoma Coptidis and Cortex Phellodendri samples. This method can also be used to identify two common species of Rhizome Coptidis, i.e., C. chinensis and C. deltoidea, and two species of Cortex Phellodendri, i.e., P. chinensis and P. amurense. From the experiment results, there are thirteen, twelve and seven common components found in samples Rhizoma Coptidis, P. amurense and P. chinensis, respectively. Nine compounds in Rhizoma Coptidis were identified to be alkaloids. The common components in Cortex Phellodendri included four alkaloids and two lactones, i.e., obaculacotone and obacunone, present in all samples of P. amurense. / High Performance Liquid Chromatography-Atmospheric Pressure Chemical Ionization Mass-Spectrometry has been applied to the analysis and standardization of Chinese Herbal Medicines. The applications included quantitative study of Astragaloside in Radix Astragali, investigation on the chromatographic fingerprint of Radix Astragali, differentiation of Cortex Phellodendri and Rhizoma Coptidis, and identification of constituents in Sanhuang Xiexin Decoction. / In the quantitative study of Astragaloside, an Multiple Reaction Monitoring scan mode was used. The linearity between 2 and 500 mg/L is 0.9996. The precision of injection and reproducibility of method is 1.72% and 3.27% respectively. A total of 20 samples from local market and mainland China were analyzed and the results are comparable to those obtained from HPLC-ELSD analysis. / The present study also proposed a HPLC separation and online identification for the 15 constituents in a composite Chinese herbal formula, the Sanhuang Xiexin Decoction. It provided a possible starting point to evaluate related herbal preparations containing Rhizoma Coptidis, Radix Scutellariae and Rhizoma Rhei. Thirteen constituents in the decoction were identified, including five major alkaloids from Rhizoma Coptidis, five anthraquinones from Rhizoma Rhei and two favonoids and one glycoside from Radix Scutellariae. / "November 2007." / Adviser: Chi Chun Tao. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4726. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 177-200). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
95

Southern African plants used to treat central nervous system related disorders.

Stafford, Gary Ivan. January 2009 (has links)
The majority of the population in South Africa use traditional health care to treat various mental conditions. This thesis has two main objectives; to bring together a comprehensive and detailed record of psychotropic plants used in southern Africa by indigenous peoples for medicinal or cultural purposes. Secondly, this research attempts to investigate the validity and rationale of the use of these plants by screening them in various biological assays for psychotropic activity. Plants were selected, based on their traditional use and availability, and were screened in four assays, which detect biological activity of a useful nature. A number of in vitro enzymatic and neuronal signal transduction assays were employed in this thesis, the inhibition of the serotonin reuptake transporter protein (SERT); inhibition of catabolic enzymes (e.g. acetylcholinesterase, monoamine oxidase); GABAA- benzodiazepine receptor binding. The influence of legislation, past and present, on the state of traditional medicine is highlighted. Aspects of the philosophies and practises of the various practitioners of South African traditional medicine will be discussed. An annotated list compiled from available ethnobotanical literature of plants traditionally used for central nervous system-related purposes is provided. It contains more than 330 species, from 94 families, which are currently used or have been used for cultural, medicinal and recreational purposes related to the central nervous system (CNS). Where available, information pertaining to plant part used, preparation method, dosage, route of administration, known and potentially active constituents are included. Seventy five extracts from 34 indigenous plant species used in South African traditional medicine or taxonomically related to these were investigated for their affinity to the serotonin reuptake transport protein, making use of an in vitro [3H]-citalopram serotonin reuptake transport protein binding assay. Aqueous and 70% ethanolic extracts of various plant parts were screened and 45 extracts derived from 15 plant species showed affinity. The affinity of 12 extracts from four plants was characterized as high (more than 50% inhibition at 5, 1, and 0.5 mg/ml). Plant species with high affinity to the serotonin reuptake transport protein included Agapanthus campanulatus, Boophone disticha, Datura ferox and Xysmalobium undulatum. Agapanthus campanulatus yielded high activity in aqueous extracts from leaves and flowers. B. disticha showed high activity both in aqueous and ethanolic extracts of leaves and bulbs. D. ferox showed high activity in aqueous extracts from the seeds and X. undulatum showed high activity in the ethanolic extract of the whole plant. Two compounds, buphanadrine and buphanamine, were isolated by bioassay-guided fractionation on vacuum-liquid-chromatography (VLC) and preparative thin-layer-chromatography (TLC) from B. disticha. The structures of the compounds were determined by 1H and 13C NMR. Fractions were tested for affinity to the serotonin transporter in a binding assay using [3H]-citalopram as a ligand. The IC50 values of buphanidrine and buphanamine were 274 ìM (Ki = 132 ìM) and 1799 ìM (Ki = 868 ìM), respectively. The two alkaloids were also tested for affinity to the 5HT1A receptor, but only showed slight affinity. Aqueous and ethanol extracts of 43 plants that are traditionally used to treat against epilepsy and convulsions were initially tested in the GABAA-benzodiazepine receptor binding assay, where the binding of 3H-Ro 15-1788 (flumazenil) to the benzodiazepine site is measured. The GABAA-benzodiazepine receptor complex is involved in epilepsy and convulsions. Out of the 118 extracts tested, one aqueous and 18 ethanol extracts showed activity. The most active extracts were the ethanolic leaf extracts of Searsia tridentata, Searsia rehmanniana and Hoslundia opposita and the ethanolic corm extract of Hypoxis colchicifolia, which all showed good dose-dependent activity. A further forty-six ethanol extracts from another 35 species, both indigenous and exotic that are traditionally used predominantly as sedatives or to treat various CNS-related ailments were tested in the GABAA-benzodiazepine receptor-binding assay. Out of the 46 extracts tested, seven showed good activity and 10 showed moderate activity. The most active extracts were the ethanolic leaf extracts of Arctopus echinatus, Artemisa afra, four Helichrysum species and Mentha aquatica which all showed good dose-dependent activity. Two biflavonoids with activity in the 3H-Ro 15-1788 (flumazenil) binding assay were isolated by high pressure liquid chromatography (HPLC) fractionation of the ethanol extract of the leaves from Searsia pyroides. The structures of the two biflavonoids were elucidated by nuclear magnetic resonance spectroscopy (NMR) to be agathisflavone and amentoflavone. Agathisflavone and amentoflavone competitively inhibited the binding of 3H-Ro 15-1788 with a Ki of 28 and 37 nM, respectively. Extracts of Searsia dentata and Searsia pentheri were not as active as the extract from Searsia pyroides; both were found to contain apigenin and agathisflavone. The monomer apigenin, agathisflavone and amentoflavone were fitted into a pharmacophore model for ligands binding to the GABAA receptor benzodiazepine site. This reflected the affinities of the compounds in the [3H]-flumazenil binding assay. Mentha aquatica, a mint that is found in Europe and Africa, is used in Zulu traditional medicine for spiritual purposes. The ethanolic leaf extract showed a strong affinity to the GABA-benzodiazepine receptor. Viridiflorol from the essential oil and (S)-naringenin from an ethanolic extract was isolated by bioassay-guided fractionation using binding to the GABA-benzodiazepine site. Viridiflorol had an IC50 of 0.19 M and (S)-naringenin of 0.0026 M. Twenty plants used in Zulu traditional medicine for several CNS-related ailments were screened for MAO inhibition and specific MAO-B inhibition activity. MAO-B inhibitors are currently employed in the treatment of neurodegenerative related illnesses such as Parkinson's and Alzheimer's diseases. A photometric peroxidase linked assay was used to determine the inhibition of the oxidative deamination of tyramine by MAO isolated from rat liver. Ruta graveolens exhibited the best MAO inhibitory activity (ethyl acetate leaf extract = IC50 5 ± 1 ìg/ml, petroleum ether extract = 3 ± 1 ìg/ml) and specific MAO-B inhibition (ethyl acetate leaf extract = IC50 7 ± 6 ìg/ml petroleum ether extract = 3 ± 1 ìg/ml). Schotia brachypetala, Mentha aquatica and Gasteria croucheri also exhibited good MAO-B inhibition activity. Six extracts of varying polarity of Mentha aquatica were tested in a photometric peroxidase linked MAO bioassay. The 70% ethanol extract had highest inhibitory activity. (S)-Naringenin was isolated from the extract by bioassay guided fractionation on VLC and preparative TLC. The structure of the compound was determined by 1H, 13C and 13C-DEPT NMR and optical rotation. The IC50 values for MAO inhibition by naringenin were 342 ± 33 ìM for the rat liver mitochondrial fraction, 955 ± 129 ìM for MAO-A and 288 ± 18 ìM for MAO-B respectively. South African traditional medicine clearly utilizes many botanical species with CNS-related activity. Only a small number of the more than 330 southern African plant species reported to treat or alter the CNS have been scientifically evaluated. To date very few of the active compounds have been isolated and identified. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
96

Artificial neural networks for the classification of Meliaceae extractives.

Fraser, Leigh-Anne. January 1998 (has links)
The goal of this project was the development of a computer-based system using artificial intelligence to classify the limonoids, protolimonoids and triterpenoids isolated from the family Meliaceae by the Natural Products Research Group of the University of Natal, Durban. A database of samples was obtained between 1991 and 1996, part of which time the author was a member of the group and isolated compounds from Turraea obtusifolia and Turraea floribunda. Over and above the problem of complexity and similarity in structures of the above mentioned natural products, are other difficulties. These include very small amounts of sample being isolated producing very weak peak signals in the C-13 NMR spectra, extraneous peaks in the NMR spectra due to different impurities and instrument noise, non-reproducible spectra due to the pulsed Fourier transform intervals and the nuclear Overhauser effect, impure samples often isolated as stereoisomeric mixtures or as mixed esters and superposition of peak signals in the NMR spectra due to carbons in the same environment within the same compound. These factors make identification by traditional computational and expert systems impossible. As a result of these shortcomings, the author has developed a novel approach using artificial neural network techniques. The artificial neural network system developed used real data from the 300 MHz NMR spectrometer in the Department of Chemistry, Durban. The system was trained to discriminate between limonoids, triterpenoids and flavonoids/coumarins from the C-13 NMR spectra of pure, impure and unseen compounds with an accuracy of better than 90%. Further differentiation of the glabretals from the rest of the protolimonoids as well as from the rest of the triterpenoids showed similarly significant results. Finally, individual limonoid discrimination within the limonoid dataset was extremely successful. Apart from its application to the extractives from Meliaceae, the methodology and techniques developed by the author can be applied to other sets of extractives to provide a robust method for the spectral classification of pre-identified natural products. / Thesis (Ph.D.)-University of Natal, Durban, 1998.
97

Análise química e biológica de metabólitos voláteis isolados de plantas das famílias Myrtaceae e Zingiberaceae

Ribeiro, Jane Cristina Lara 26 April 2013 (has links)
CAPES / Neste trabalho foi investigado a composição química de metabólitos voláteis extraídos de quatro plantas Pimenta pseudocaryophyllus (Myrtaceae), Psidium cattleyanum (Myrtaceae), Hedychium coronarium (Zingiberaceae) e Costus spiralis (Zingiberaceae) através da cromatografia gasosa acoplada à espectrometria de massas (CG/MS). São apresentados resultados relativos à composição química sazonal do óleo essencial obtido das folhas de Pimenta pseudocaryophyllus, em amostras coletadas bimestralmente de janeiro a novembro de 2009. Em novembro foram observadas as maiores concentrações relativas aos constituintes majoritários do óleo essencial das folhas dessa espécie, sendo o chavibetol (70,90%) e metileugenol (20,70%). Além disso, foram avaliadas as atividades antimicrobianas do óleo essencial das folhas de P. pseudocaryophyllus através de técnicas de difusão com discos e microdiluição em caldo. O chavibetol, composto majoritário mostrou-se o responsável pela maior atividade antifúngica. São apresentados também a sazonalidade do óleo essencial obtido do rizoma de Hedychium coronarium, em amostras coletadas bimestralmente de março a janeiro de 2012 a 2013. Em março foram observadas as maiores concentrações relativas aos constituintes majoritários do óleo essencial do rizoma dessa espécie, sendo β- pineno (31,82%) e 1,8 cineol (28,30%). O estudo populacional dos metabólitos voláteis das folhas do Psidium cattleyanum coletados em Curitiba-PR identificou vinte e oito componentes sendo majoritário o lavander lactona (12,26%). Por outro lado, trinta e um compostos foram identificados no óleo essencial dessa mesma espécie em ecossistema de restinga, sendo majoritário o α-tujeno (25,20%). A extração de metabólitos voláteis das flores H. coronarium e brácteas da C. spiralis foi efetuada através do processo de aeração, fornecendo o linalol (43,58%) e o β- pineno (23,25%), respectivamente como os compostos majoritários. / In this work we investigated the chemical composition of volatile metabolites extracted from four plants Pepper pseudocaryophyllus (Myrtaceae), Psidium cattleyanum (Myrtaceae), Hedychium coronarium (Zingiberaceae) and Costus spiralis (Zingiberaceae) by gas chromatography-mass spectrometry (GC / MS). Results are presented relative to seasonal chemical composition of the essential oil obtained from the leaves of Pepper pseudocaryophyllus in samples collected bimonthly from January to November 2009. In November showed the highest concentrations on the major constituents of the essential oil from the leaves of this species, being chavibetol (70.90%) and methyleugenol (20.70%). Furthermore, we evaluated the antimicrobial activity of essential oil from the leaves of P. pseudocaryophyllus through techniques of diffusion disk and broth microdilution. The chavibetol, major compound was shown to be responsible for the greatest antifungal activity. We present also the seasonality of the essential oil obtained from the rhizome of Hedychium coronarium in samples collected bimonthly from March to January 2012-2013. In March the highest concentrations were observed on the major constituents of the essential oil of the rhizome of this species, and β-pinene (31.82%) and 1,8 cineole (28,30%). The population study of volatile metabolites from the leaves of Psidium cattleyanum collected in Curitiba identified twenty-eight components, the majority being lavander lactone (12.26%). Conversely, thirty-one compounds were identified in the essential oil of the species ecosystem in restinga provided the major constituent being the α-tujeno (25.20%). The extraction of volatile metabolites of flowers H. coronarium and bracts of C. spiralis was effected through the aeration process, providing linalool (43.58%) and β-pinene (23.25%), respectively as the major compounds.
98

Análise química e biológica de metabólitos voláteis isolados de plantas das famílias Myrtaceae e Zingiberaceae

Ribeiro, Jane Cristina Lara 26 April 2013 (has links)
CAPES / Neste trabalho foi investigado a composição química de metabólitos voláteis extraídos de quatro plantas Pimenta pseudocaryophyllus (Myrtaceae), Psidium cattleyanum (Myrtaceae), Hedychium coronarium (Zingiberaceae) e Costus spiralis (Zingiberaceae) através da cromatografia gasosa acoplada à espectrometria de massas (CG/MS). São apresentados resultados relativos à composição química sazonal do óleo essencial obtido das folhas de Pimenta pseudocaryophyllus, em amostras coletadas bimestralmente de janeiro a novembro de 2009. Em novembro foram observadas as maiores concentrações relativas aos constituintes majoritários do óleo essencial das folhas dessa espécie, sendo o chavibetol (70,90%) e metileugenol (20,70%). Além disso, foram avaliadas as atividades antimicrobianas do óleo essencial das folhas de P. pseudocaryophyllus através de técnicas de difusão com discos e microdiluição em caldo. O chavibetol, composto majoritário mostrou-se o responsável pela maior atividade antifúngica. São apresentados também a sazonalidade do óleo essencial obtido do rizoma de Hedychium coronarium, em amostras coletadas bimestralmente de março a janeiro de 2012 a 2013. Em março foram observadas as maiores concentrações relativas aos constituintes majoritários do óleo essencial do rizoma dessa espécie, sendo β- pineno (31,82%) e 1,8 cineol (28,30%). O estudo populacional dos metabólitos voláteis das folhas do Psidium cattleyanum coletados em Curitiba-PR identificou vinte e oito componentes sendo majoritário o lavander lactona (12,26%). Por outro lado, trinta e um compostos foram identificados no óleo essencial dessa mesma espécie em ecossistema de restinga, sendo majoritário o α-tujeno (25,20%). A extração de metabólitos voláteis das flores H. coronarium e brácteas da C. spiralis foi efetuada através do processo de aeração, fornecendo o linalol (43,58%) e o β- pineno (23,25%), respectivamente como os compostos majoritários. / In this work we investigated the chemical composition of volatile metabolites extracted from four plants Pepper pseudocaryophyllus (Myrtaceae), Psidium cattleyanum (Myrtaceae), Hedychium coronarium (Zingiberaceae) and Costus spiralis (Zingiberaceae) by gas chromatography-mass spectrometry (GC / MS). Results are presented relative to seasonal chemical composition of the essential oil obtained from the leaves of Pepper pseudocaryophyllus in samples collected bimonthly from January to November 2009. In November showed the highest concentrations on the major constituents of the essential oil from the leaves of this species, being chavibetol (70.90%) and methyleugenol (20.70%). Furthermore, we evaluated the antimicrobial activity of essential oil from the leaves of P. pseudocaryophyllus through techniques of diffusion disk and broth microdilution. The chavibetol, major compound was shown to be responsible for the greatest antifungal activity. We present also the seasonality of the essential oil obtained from the rhizome of Hedychium coronarium in samples collected bimonthly from March to January 2012-2013. In March the highest concentrations were observed on the major constituents of the essential oil of the rhizome of this species, and β-pinene (31.82%) and 1,8 cineole (28,30%). The population study of volatile metabolites from the leaves of Psidium cattleyanum collected in Curitiba identified twenty-eight components, the majority being lavander lactone (12.26%). Conversely, thirty-one compounds were identified in the essential oil of the species ecosystem in restinga provided the major constituent being the α-tujeno (25.20%). The extraction of volatile metabolites of flowers H. coronarium and bracts of C. spiralis was effected through the aeration process, providing linalool (43.58%) and β-pinene (23.25%), respectively as the major compounds.
99

The medicinal properties of ipomoea oblongata E.Mey. ex Choisy

Polori, Ketlareng Liza January 2014 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, 2014. / Traditional medicine has been known by mankind since ancient times as a healthcare system. All cultures have used herbs throughout history and it was an integral part of the development of modern civilization. Primitive man observed and appreciated the great diversity of plants available to him. Plants provided food, clothes, shelter and medicine and still play a vital role in rural villages of South Africa. The medicinal uses of plants and animals have been developed through trial and error. Herbal plants produce and contain a wide variety of chemical substances that act upon the body’s immune system. The medicinal properties of Ipomoea oblongata (E.Mey.ex Choisy) in this study was to determine the phytochemical content, antioxidant, anti-cancer and anti-diabetic properties of I. oblongata (Mothokho), a medicinal plant used by traditional medical practitioners of Thaba-Nchu in the Free State. The study was carried out in order to validate the ethnomedicinal claims made by the traditional medical practitioners and to evaluate the plant’s potential as a novel therapeutic agent. Twelve traditional medical practitioners of the Kopanang Dingaka Association were interviewed on the knowledge and use of I. oblongata (Mothokho). The phytochemical constituents of the plant were determined using standard screening methods. Testing for antioxidant properties (free radical scavenging activity) was carried out by means of the 2, 2- diphenylpicrylhydrazyl (DPPH) assays. The Sulforhodamine B assay was used to screen for anti-cancer activity in breast (MCF7), colon (HCT116) and prostate (PC3) cancer cell lines. Glucose uptake in C2C12 muscle cells was used to evaluate the anti- iii diabetic potential of I. oblongata. Methanol extract was fractionated using Ultra-Pure Liquid Chromatography (UPLC) to identify active compounds. The traditional medical practitioners cited the plant roots as the main ingredient in the treatment of respiratory infections, sexually transmitted infections, postnatal womb treatments, inflammation, arthritis, wounds and cancer. The methanol extract of I. oblongata showed remarkable (99.03%, 98.39, 71.31%) antioxidant potential in all triplicates tested which explains its use in oxidative stress-related diseases such as arthritis and cancer. Phytochemical tests showed the presence of carbohydrates, glycosides, steroids, terpenoids, alkaloids, flavonoids and tannins. However, the extracts were inactive against the cancer cell lines used. Glucose uptake by the C2C12 muscle cells was increased by over 150% and was comparable to that of insulin and metformin, suggesting good anti-diabetic activity. Predicted compounds found were dihydroquercetin pentaacetate, actinorhodin and actinorhodine, using Chemspider analysis. These are possible compounds that could be found in the Ipomoea oblongata extracts when using nuclear magnetic resonance (NMR) to determine the structure and names of the active compounds. Ethnobotanical uses of Ipomoea oblongata were found to have a link with other ethnobotanical studies to capture the indigenous knowledge, culture and therapeutic uses. The phytochemical results of Ipomoea oblongata can contribute to the knowledge of new drug development as indicated by literature (Harbone; 1973, Soforowa, 1993; De et al., 2010) that plants contain phytochemical contents and phenolic compounds that are valuable as medicinal properties. Methanolic extract of Ipomoea oblongata presented high levels of antioxidant activity respectively, which can become a potential iv antimicrobial agent and remedy oxidative stress related diseases. The anticancer properties were inactive and the cytotoxicity levels were found to below in I. oblongata. Low levels of cytotoxicity allow medicinal plants to be consumed by humans with fewer side effects however doses must be standardized. High levels of glucose uptake in muscle cells were indicated from the aqueous extract of Ipomoea oblongata, therefore showing great potential as an antidiabetic agent. Many medicinal plants have been validated as antidiabetic therapeutic agents in South Africa and the world. New treatment of cancer, diabetes, bacterial and viral infections is required from natural products that are cost effective with minimal side effects that can be used in health care systems. There is a correlation between the medicinal properties found in I. oblongata and the ethnomedicinal uses cited by the traditional medical practitioners. The plant I. oblongata has six ethno-pharmaceutical uses. I. oblongata is a good source of anti-diabetic and antioxidant agents that can be developed further. However the plant is not a good source of anticancer properties. Future research will be into the isolation and identification of the active compounds.
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Authentication of traditional Chinese medicines Radix Aconiti and Radix Aucklandiae by DNA and chemical technologies.

January 2006 (has links)
Shum Ka Chiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 174-182). / Abstracts in English and Chinese. / Acknowledgement --- p.ii / Abstract --- p.iii / 摘要 --- p.vi / Table of content --- p.viii / List of figures --- p.xvi / List of tables --- p.xxii / Abbreviations --- p.xxv / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Importance of authentication of Traditional Chinese Medicines --- p.1 / Chapter 1.1.1 --- Confusing nomenclatures --- p.1 / Chapter 1.1.2 --- Similar morphologies of different medicinal materials --- p.2 / Chapter 1.1.3 --- Toxicities of medicinal materials --- p.2 / Chapter 1.1.4 --- Conservation of natural products --- p.2 / Chapter 1.2 --- TCM listed in the Pharmacopoeia of People's Republic of China --- p.3 / Chapter 1.3 --- Overview of mis-use and intoxication of TCM --- p.4 / Chapter 1.4 --- Ordinances regulating Chinese medicines as natural products --- p.7 / Chapter 1.4.1 --- Laws governing Chinese medicine --- p.7 / Chapter 1.4.2 --- Laws governing endangered species --- p.8 / Chapter 1.5 --- Current technologies in the authentication of Traditional Chinese Medicines and their limitations --- p.9 / Chapter 1.6 --- Historical applications of Radix Aconiti --- p.12 / Chapter 1.7 --- Modern applications of Radix Aconiti --- p.16 / Chapter 1.8 --- Research on Radix Aconiti and its chemical components --- p.17 / Chapter 1.8.1 --- Chemistry --- p.17 / Chapter 1.8.2 --- Pharmacology --- p.19 / Chapter 1.8.3 --- Molecular interaction --- p.22 / Chapter 1.9 --- Brief review on the systematics and phylogeny of Aconitum --- p.23 / Chapter 1.10 --- Historical applications of Radix Aucklandiae and related materials --- p.25 / Chapter 1.11 --- Modern applications of Radix Aucklandiae and related material --- p.27 / Chapter 1.12 --- Research on Aucklandiae and related material and their chemical components --- p.28 / Chapter 1.12.1 --- Chemistry --- p.28 / Chapter 1.12.2 --- Pharmacology --- p.29 / Chapter 1.13 --- Brief review on the systematics and phylogeny of Aucklandia and related medicinal species --- p.31 / Chapter 1.14 --- Authentication by DNA sequencing --- p.33 / Chapter 1.14.1 --- Introduction --- p.33 / Chapter 1.14.2 --- Criteria of sequence markers --- p.36 / Chapter 1.14.3 --- Model used to process polymorphism in DNA sequences --- p.37 / Chapter 1.15 --- Screening for novel markers --- p.38 / Chapter 1.15.1 --- Reason for screening novel markers --- p.38 / Chapter 1.15.2 --- Basic principle --- p.39 / Chapter 1.16 --- Introduction to gas chromatography- mass spectrometry --- p.40 / Chapter 1.16.1 --- Basic principles and components of GC-MS --- p.41 / Chapter 1.16.2 --- Advantages and limitations of GC-MS --- p.42 / Chapter 1.16.3 --- Usage of GC-MS on natural product analysis --- p.43 / Chapter 1.16.4 --- Chemometric analysis --- p.44 / Chapter 1.17 --- Objectives --- p.46 / Chapter Chapter 2. --- Materials and Methods --- p.47 / Chapter 2.1 --- Plant samples --- p.47 / Chapter 2.1.1 --- Samples of Aconitum --- p.47 / Chapter 2.1.2 --- Samples of Aucklandia and related species --- p.51 / Chapter 2.2 --- DNA extraction method --- p.58 / Chapter 2.2.1 --- Reagents --- p.58 / Chapter 2.2.2 --- Methods --- p.59 / Chapter 2.3 --- Chemical extraction methods --- p.61 / Chapter 2.4 --- Chemical standard extraction and purification method --- p.62 / Chapter 2.5 --- DNA sequencing --- p.63 / Chapter 2.5.1 --- Reagents --- p.63 / Chapter 2.5.2 --- Methods --- p.65 / Chapter 2.6 --- Genomic subtraction --- p.70 / Chapter 2.7 --- Search for species-specific markers from the subtraction library --- p.74 / Chapter 2.8 --- Gas chromatography- mass spectrometry --- p.74 / Chapter 2.9 --- GC-MS chemometric analysis --- p.75 / Chapter Chapter 3. --- Authentication of Aconitum by DNA Sequencing --- p.76 / Chapter 3.1 --- Introduction --- p.76 / Chapter 3.2 --- Methods --- p.77 / Chapter 3.3 --- Results - 5S spacer --- p.77 / Chapter 3.3.1 --- Sequence information --- p.77 / Chapter 3.3.2 --- Sequence similarity --- p.78 / Chapter 3.3.3 --- Phylogram study --- p.81 / Chapter 3.4 --- Results -psbA-trnH --- p.85 / Chapter 3.4.1 --- Sequence information --- p.85 / Chapter 3.4.2 --- Sequence similarity --- p.85 / Chapter 3.4.3 --- Phylogram study --- p.87 / Chapter 3.5 --- Discussion --- p.91 / Chapter 3.5.1 --- Overview of nuclear ribosomal 5S spacer --- p.91 / Chapter 3.5.2 --- Extensive polymorphism of 5S spacer --- p.91 / Chapter 3.5.3 --- Distribution of samples in the phylograms constructed by 5S spacer --- p.93 / Chapter 3.5.4 --- Utility of 5S spacer for authentication --- p.94 / Chapter 3.5.5 --- Overview of psbA-trnH spacer --- p.94 / Chapter 3.5.6 --- Distribution of samples in the phylograms constructed by psbA-trnH spacer --- p.95 / Chapter 3.5.7 --- A distinctive region of inversion --- p.96 / Chapter 3.5.8 --- Utility of psbA-trnH for authentication --- p.97 / Chapter Chapter 4. --- Screening for Novel Markers for Authentication of Aconitum --- p.98 / Chapter 4.1 --- Introduction --- p.98 / Chapter 4.2 --- Methods --- p.99 / Chapter 4.3 --- Results - subtracted clones --- p.99 / Chapter 4.4 --- Results - SSH6 --- p.104 / Chapter 4.4.1 --- Sequence information --- p.104 / Chapter 4.4.2 --- Sequence similarity --- p.105 / Chapter 4.5 --- Results-SSH15 --- p.107 / Chapter 4.5.1 --- Sequence information --- p.107 / Chapter 4.5.2 --- Sequence similarity --- p.107 / Chapter 4.5.3 --- Phylogram study --- p.109 / Chapter 4.6 --- Results-SSH45 --- p.113 / Chapter 4.6.1 --- Sequence information --- p.113 / Chapter 4.6.2 --- Sequence similarity --- p.113 / Chapter 4.6.3 --- Phylogram study --- p.115 / Chapter 4.7 --- Discussion --- p.119 / Chapter 4.7.1 --- Utility of subtraction in screening markers --- p.119 / Chapter 4.7.2 --- SSH6 --- p.121 / Chapter 4.7.3 --- SSH15 --- p.122 / Chapter 4.7.4 --- SSH45 --- p.123 / Chapter 4.7.5 --- Hybridization in Aconitum --- p.124 / Chapter 4.7.6 --- Inferring species identities of samples from the market --- p.126 / Chapter 4.8 --- Conclusion --- p.128 / Chapter Chapter 5. --- Assessment of Aucklandia lappa and Related Species by GC-MS --- p.129 / Chapter 5.1 --- Introduction --- p.129 / Chapter 5.2 --- Methods --- p.130 / Chapter 5.3 --- Results --- p.130 / Chapter 5.3.1 --- Extraction of essential oil --- p.130 / Chapter 5.3.2 --- GC-MS analysis --- p.131 / Chapter 5.3.3 --- Peak alignment and hierarchical cluster analysis --- p.133 / Chapter 5.3.4 --- Purification of chemical markers from Aucklandia lappa --- p.148 / Chapter 5.3.5 --- Standardization of the purified chemical markers --- p.148 / Chapter 5.3.6 --- Quantitative analysis of chemical markers --- p.152 / Chapter 5.4 --- Discussion --- p.154 / Chapter 5.4.1 --- Analysis of chemical composition --- p.154 / Chapter 5.4.2 --- A comparison on chemometric methods --- p.154 / Chapter 5.4.3 --- Similarity of chemical profiles --- p.156 / Chapter 5.4.4 --- Dendrogram analysis --- p.157 / Chapter 5.4.5 --- Utility of GC-MS in authentication of A. lappa and related species --- p.159 / Chapter 5.4.6 --- Limitations --- p.159 / Chapter 5.4.7 --- Comparison with molecular data --- p.161 / Chapter 5.4.8 --- Contents of dehydrocostuslactone and costunolide --- p.163 / Chapter 5.4.9 --- Locality study --- p.164 / Chapter 5.5 --- Conclusion --- p.165 / Chapter Chapter 6. --- General Discussion --- p.167 / Chapter 6.1 --- DNA sequencing --- p.168 / Chapter 6.2 --- Genomic subtraction --- p.169 / Chapter 6.3 --- Future work on molecular authentication --- p.170 / Chapter 6.4 --- Future work on authentication of Aconitum --- p.170 / Chapter 6.5 --- Gas chromatography- mass spectrometry --- p.171 / Chapter 6.6 --- Future work on authentication by GC-MS --- p.172 / Chapter 6.7 --- Future work on authentication of Aucklandia lappa and related species … --- p.173 / References --- p.174 / Appendix A. Sequence Alignment of 5S Spacer from Aconitum Species --- p.183 / Appendix B. Sequence Alignment of psbA- trnH Spacer from Aconitum Species --- p.188 / Appendix C. Sequences of Subtracted Clones from Aconitum --- p.191 / Appendix D. Sequence Alignment of SSH6 from Aconitum Species --- p.194 / Appendix E. Sequence Alignment of SSH15 from Aconitum Species --- p.195 / Appendix F. Sequence Alignment of SSH45 from Aconitum Species --- p.200 / Appendix G. Gas Chromatograms of Essential Oil Extracts of Aucklandia lappa and Related Species --- p.202

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