Thesis (MTech. degree in Pharmaceutical Sciences)--Tshwane University of Technology, 2008. / The aim of the study is to investigate whether the chemical composition and antimicrobial activity of orally administered medicinal plants are affected by in vitro dissolution and gastrointestinal absorption processes. Few in vitro screening assays for biological activities of plant extracts consider the effect of the gastrointestinal system. This is an important factor for the bioavailability of plant extracts intended to be administered via the oral route. In this study, crude water and methanol extracts of selected plants (green tea, 'buchu', thyme, sage and wild camphor) were prepared and exposed to simulated gastric fluid and simulated intestinal fluid during dissolution studies. The crude extracts and resulting simulated gastric fluid and simulated intestinal fluid products were screened for antimicrobial activity.

Diabetes mellitus (DM) has become a global threat in developing and developed countries, where diabetic patients are more prone to cardiovascular complications, a condition called diabetic cardiomyopathy. Studies have shown a direct link between hyperglycaemia and an increase in the production of reactive oxygen species in cardiac cells leading to diabetic cardiomyopathy. This study tests oleanolic acid, a bioactive compound from the plant Syzigium aromaticum as an antioxidant which could have a potential role in management of DM. Aims i) To extract Oleanolic acid (OA) from Syzigium aromaticim, ii) Investigate the antioxidant effects of plant derived OA in an in-vitro model of hyperglycaemia induced oxidative stress. Methods The flower buds of the Syzigium aromaticim [(Linnaeus) Merrill & Perry] (Myrtaceae) plant (commonly called cloves) were used to isolate OA. The ethyl acetate solubles from the cloves were subjected to chromatographic fractionation to yield OA powder. Spectroscopic analysis was done using 1D and 2D 1H and 13C NMR techniques for the identification of the structure of the compound. This compound was then used in vitro to test for its antioxidative properties. H9C2 cardiac myoblasts were employed which were treated with normoglycaemic (5.5 mM) and hyperglycaemic (33 mM) glucose conditions. The cells were then treated with oleanolic acid to test for its antioxidant properties. We looked at a dose-dependent (0, 20, 50 μM) and time-dependent effects of OA treatment (6 and 24 hrs) following 48 hours glucose exposure. ROS levels were measured using H2DCF-DA fluorescence staining using microscopy and flow cytometry techniques for analysis. xviii Results Recrystallisation of the powder with ethanol and inspection of the 1 and 2- dimensional 1H- and 13C-NMR spectra of the compound with comparison to literature data confirmed OA molecular structure and IUPAC numbering similar to that of literature characterized and confirmed the structure of oleanolic acid. In cell specific data high glucose treatments on H9C2 cells showed increased ROS production (22 ± 6 % and 20 ± 7 % n= 3 p< 0.01) for 6 and 24 hrs treatments, respectively, compared to their normoglycaemic control groups. The 6 h OA treated group showed a decrease in ROS production with 26.6 ± 17.4 % for the 20 μM while for 50 μM there was a 37.7 ± 14.3% decrease. A ROS reduction trend was observed in the normoglycaemic group, but this was significant at 24 hrs with 46.8 ± 45.3% and 57.3 ± 9 % for both 20 and 50 μM treatments, respectively. The 24 hrs OA treated group showed a dose-dependent decrease in ROS with 50 μM more pronounced (80.7% ± 4.5 %). The 20 μM OA treatments also showed a 15.7 ± 19 % decrease in ROS. Discussion In the present study, we have evaluated the antioxidant effects of OA in vitro following extraction of the compound from Syzigium aromaticim. The oxidative stress induced by hyperglycaemia was attenuated by oleanolic acid and this also translated into decreased ROS suggesting its use as an antioxidant in alleviating cardiovascular complications associated with diabetes mellitus.

This research has been done on the riverside of the Žeimena. This territory belongs to the Pabrade town. After having done the research of flora of herbs on the riverside of the Žeimena in 2001 - 2004 from 43 families and 90 genera there have been inventoried 105 varieties Asteraceae (16), Rosaceae (12 varieties), Lamiaceae (8), Polygonaceae (6), Salicaceae (5), Apiaceae (5) in over families - less than 5 varieties. The varieties of herbs growing in Pabradės forestry are Vaccinium myrtillus, Vaccinium vitis-idaea, Filipendula ulmaria, Urtica dioica; Žeimenos forestry - Vaccinium myrtillus, Fragaria vesca, Achillea millefolium and Filipendula ulmaria; Magūnų forestry - Juniperus communis, Vaccinium myrtillus, Vaccinium vitis-idaea, Acorus calamus, Padus avium and Urtica dioica. According to active substances for rohich those herbs are being collected 26% of them belong to the essential oil group, 21% to the glucosidic group, 5% to the ferment group, 5% to the nucous group and 4% to the resinous group. Appreciate to the farm meaning 82% have genetic conseąuehce, 15% have local output and 2% have production consequence. In most cases herbs are collected from June till August because of actine substances concentrations in 65% of the herbs during that period of time. In this work has been established a fact that the same species of herbs in Žeimena, Pabradė and Magūnai forestries differ in their morphological and biological characteristics and efficiency, for example, Vaccinium... [to full text]

<p>Aim: To determine whether there was any significant difference in the antimicrobial activity of 4 herbal toothpastes against cultures of 3 primary plaque colonizers (Streptococcus mutans, Streptococcus sanguinis and a non-specific &alpha / -heamolytic streptococcus).</p>

<p>Infusions, decoctions, alcoholic preparations and other dosage forms of Artemisia afra are frequently used in South African traditional medicine. Generally when these preparations are made without applying good manufacturing practices they do not meet microbial quality control standards, safety and toxicity criteria and encourage poor patients compliance. To overcome the aforementioned disadvantages of traditional dosage forms a sold dosage form, i.e. a table might be recommended. The first objective of this study was to formulate and manufacture a rapid release tablet dosage of Artemisia afra that would contain an amount of plant material equivalent to that found in its traditional liquid dosage forms and that would meet conventional pharmaceutical standards. The second objective was to conduct a pilot study to obtain a preliminary profile of the bioavailability of select flavonoids presents in both the tablet and traditional liquid preparation of Artemisia afra in humans.</p>

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 81-92) Also available in print.

Thesis (Ph. D.) (Botany)--University of Pretoria, 2002.

Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 129-156). Also available in electronic format on the Internet.

Thesis (Ph.D.)--University of Western Sydney, 2007. / "A thesis submitted to the University of Western Sydney, College of Health and Science, School of Biomedical and Health Sciences in fulfilment of the requirements for the degree of Doctor of Philosophy." Includes bibliography.

Thesis (Ph.D.)--University of Western Sydney, 2008. / A thesis presented to the University of Western Sydney, College of Health and Science, Centre for Complementary Medicine, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographies.