Thesis (MTech (Biomedical Sciences))--Cape Peninsula University of Technology, 2015. / Wastewater treatment plants (WWTPs) are designed to remove/decrease conventional pollution parameters from the wastewater influent, so that the final effluent (run off) does not compromise the receiving surface water source. However, as hospital and clinical effluent may form part of the initial influent at a WWTP, bacteria may be exposed to various antibiotics or pharmaceuticals throughout the various stages of primary, secondary and tertiary processes utilised to remove or reduce the level of pollutants. Numerous studies have then indicated that WWTPs have become potential reservoirs for antibiotic resistant bacteria (ARB) and due to ineffective treatment practices, antibiotics are being released into the environment. Consequently, research has shown that relatively low concentrations of these compounds still promotes the development of bacterial resistance, which potentiates the rapid spread of ARB in the environment. The primary aim of this study was thus to identify and trace the antibiotic resistant strains of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) throughout the Stellenbosch WWTP. This was done in order to determine the persistance of the ARB organisms at the various stages of treatment and to ascertain which identification and antibiotic resistance detection methods are ideal for the routine application and detection of these organisms. / National Research Foundation

Orientador: Marcelo Brocchi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T01:54:39Z (GMT). No. of bitstreams: 1 Gosse_JessicaThandara_M.pdf: 9918536 bytes, checksum: dc4c91a89de0bb62c2d5c3f1c2ea0b3c (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital quando for liberada / Abstract: The abstract is available with the full electronic document when available / Mestrado / Genetica de Microorganismos / Mestra em Genética e Biologia Molecular

Orientador: Marcelo Brocchi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T15:34:06Z (GMT). No. of bitstreams: 1 Lima_BrunadeAraujo_D.pdf: 3794605 bytes, checksum: 178a4bf447e5292f789a4713d5500b38 (MD5) Previous issue date: 2013 / Resumo: A violaceína é um pigmento violeta produzido por algumas espécies bacterianas de origem ambiental, tais como Chromobacterium violaceum e Janthinobacterium lividum. Esta molécula apresenta várias propriedades biológicas incluindo antibacteriana, antifúngica, antiviral, antiprotozoária e antitumoral, apesar de sua função exata na fisiologia dos micro-organismos que a produz, ainda é desconhecido. No presente trabalho, a atividade antimicrobiana da violaceína produzida comercialmente, o extrato semi purificado e nanopartículas de vanadato de prata foram avaliados contra espécies de bacterianas gram-positivas e gram-negativas. A violaceína exibiu efeito antimicrobiano contra Staphylococcus aureus resistente à meticilina (MRSA) e Enterococcus resistente à vancomicina (VRE), que são micro-organismos frequentemente relacionados com infecções adquiridas em hospitais. Os valores de MIC (concentração inibitória mínima) e MBC (concentração bactericida mínima) da violaceína produzida comercialmente foram de 0,625 ?M e 1,25 ?M respectivamente e, análise de curvas de crescimento e tempo-morte revelaram um efeito antibacteriano durante 12 horas contra MRSA. A microscopia eletrônica de transmissão mostrou os efeitos da violaceína com alterações morfológicas e ultra estruturais, incluindo alterações na parede celular e formação de septos de divisão anormais. Nos resultados obtidos das análises de proteômica e transcriptoma a violaceína afetou a expressão de várias classes funcionais de proteínas e genes em MRSA, incluindo processos biológicos em biossíntese da parede celular e divisão celular que corroboram as alterações ultra estruturais visualizadas. Em conclusão, a violaceína produzida comercialmente demonstrou atividade antimicrobiana para S. aureus MRSA e pela primeira vez, os efeitos da violaceína sobre o metabolismo de S. aureus foram descritos, indicando possíveis alvos e vias metabólicas afetadas por esta droga. No seu conjunto, estes dados indicam a violaceína como uma droga potencial para o tratamento de infecções provocadas por MRSA / Abstract: Violacein is a violet pigment produced by some bacterial species of environmental source, such as Chromobacterium violaceum and Janthinobacterium lividum. This molecule has numerous biological properties including antibacterial, antifungal, antiviral, antiprotozoal and antitumor activity, although the exact role in the physiology of producing microorganisms is still unknown. In this study, the antimicrobial activity of violacein produced commercially, semi purified extract and silver vanadate nanoparticles were evaluated against several species of gram-positive and gram-negative bacteria. Violacein exhibited antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE), microorganisms that are often related to hospital-acquired infections. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) values of violacein produced commercially were 1.25 ?M mM and 0.625 ?M respectively, and analysis of growth and time-kill curves showed an antibacterial effect against MRSA for 12 hours. The transmission electron microscopy showed the effects of violacein with morphological and ultra-structural changes, including changes in cell wall formation and abnormal division septum. The results obtained from the analysis of proteomic and transcriptomic revealed that violacein affects the expression of several functional classes of proteins and genes in MRSA, including biological processes in cell wall biosynthesis and cell division, supporting ultra-structural changes. In conclusion, violacein produced commercially demonstrated antimicrobial activity against S. aureus MRSA and the effects on the metabolism of S. aureus have been described, indicating possible targets and pathways affected by this drug. These data indicate violacein as a potential drug for the treatment of infections caused by MRSA / Doutorado / Microbiologia / Doutora em Genética e Biologia Molecular

The undeniable efficacy of medicinal plants and wide range of biological activities attributed to plant secondary metabolites are an indication that plants can serve as an excellent pool of bioactive compounds with useful therapeutic properties. The South African flora is recognised as one of the richest centres of plant diversity in the world. From this enormous biodiversity a large number of species has the potential to yield pharmacologically active compounds. C. album is an indigenous plant belonging to the Cape fynbos biome with potentially useful bioactivities. The aim of this study was to evaluate the bioactivity of C. album by screening plant extracts for antibacterial, anti-mycobacterial, antifungal, antioxidant and anti-HIV activity. For rapid and effective screening for the presence of bioactive compounds, a bioassay-guided fractionation methodology was followed. Extracts from plant material obtained from two different geographic regions, the Cape and Highveld, were prepared by liquid extraction in a ratio of 150g fresh plant material per litre solvent, either acetone or ethanol. Qualitative analysis of the crude extracts by TLC and RP-HPLC documented the multi-component plant constituents as a fingerprint, revealing a highly complex, but similar profile of extracted components in both plant groups. Preliminary identification and structural information of the bioactive components present in the active C. album extracts was obtained by a combination of preparative TLC and LC/MS. The development of resistance to all available classes of antibiotic agents, their decreased effectiveness and the re-emergence of previously uncommon infections has necessitated the search for antimicrobial substances with novel antimicrobial mechanisms. The antimicrobial activity, including the antibacterial (Gram-positive and Gram-negative), anti-mycobacterial and antifungal activity of the crude extracts were evaluated. The TLC-bioautographic method used to screen the plant extracts for antimicrobial activity, as well as the localisation of compounds with antibacterial and antifungal activity, indicated the presence of a number of inhibitory compounds with activity against all the microorganisms tested. Evaluation of the inhibitory strength of each extract by the serial microdilution assay indicated that the C. album extracts effectively inhibited all the microorganisms, with the minimum inhibitory concentrations in the low mg/ml range. The significant antimicrobial activity exhibited against all the microorganisms, especially against the Gram-negative bacteria, Mycobacterium tuberculosis and Candida albicans, could suggest the potential use of the extracts or their active constituents as therapeutic agents for the treatment of infectious diseases. The need for natural antioxidants in the health care sector and food industry, due to the role that free radicals play in the pathology of a variety of human diseases and radical-induced deterioration of food products, supported the evaluation of the free radical scavenging activity of C. album extracts against relevant free radical species. The antioxidant activity of the extracts measured using the TLC-DPPH method, revealed the presence of a number of compounds with antioxidant activity. Quantification of the radical scavenging activity by the DPPHspectrophotometric assay revealed that the acetone extracts had a higher radical scavenging activity compared to the ethanol extracts, a pattern that was also found with the fluorescencemicroplate based oxygen radical absorbance assay (ORAC), specific for peroxyl radicals. The observed antioxidant activity were correlated with the total polyphenol content of the crude extracts, determined by the Folin-Ciocalteau procedure, but not with the reducing capacity evaluated by a Fe3 + - Fe2 + reduction method. HIV/AIDS has gained significant interest due to the high mortality rate and the rapid spread of the disease. The appearance of HIV strains resistant to certain antiretroviral drugs, in addition to the high cost, severe metabolic side effects and therapeutic failure of currently available antiretroviral agents, served as motivation for evaluation of C. album for anti-HIV properties and to evaluate potential cytotoxicity of plant extracts in mammalian cell cultures. The effects of the crude extracts on the in vitro HIV-1 subtype C (the predominant HIV-1 form in South Africa) replication and cytopathic effect on CEMnkrCCR5 lymphoid cells were determined. Viability assays using tetrazolium salts and viability dyes allowed the assessment of the host cell responses in the cytotoxicity and anti-HIV screening. Assays were performed at the maximum non-toxic concentration of 50 μg/ml. Some of the plant extracts exhibited significant reduction of the virusinduced cytopathic effect and induced a significant increase in cellular viability. The effect of the extracts on HIV activity was also investigated by determining the viral p24 core protein level, an indication of the replication fitness of the virus; and a significant decrease in p24 antigen level, was found. An attempt to clarify the main active compounds and the structural elements conferring the bioactivity in the analysed systems, revealed the presence of phenolic compounds, primarily coumarins and flavonoids, which are thought to be responsible for the observed antibacterial and antioxidant activities. The results of this study indicate that C. album possess strong bioactivity that warrants further investigation. / Prof. I.A. Dubery Dr. D. Meyer

Prevention of the accumulation of undesirable biological material i.e. biofouling upon a solid surface requires the use of antifouling systems. The solid surface may be a contact lens, an off shore oil rig or a living organism. When chemicals are employed as a mechanism of defense against biofouling, the agents involved are known as antifouling agents. Marine algae must protect themselves from fouling organisms and it is thought that one of the mechanisms used by these organisms is the production of secondary metabolites with an array of biological activities. In vitro studies have shown numerous compounds isolated from marine algae to possess antibacterial, antifungal and antimacrofouling activity. The aim of this study was to evaluate the secondary metabolite extracts of selected Southern African marine macro-algae as a potential source of compounds that inhibit biofilm formation and that could be used as antifouling agents. In this project, marine macro-algae were collected from various sites along the South African coastline. Their extracts were screened for antimicrobial activity against four ubiquitous microorganisms, Staphylococcus aureus, Klebsiella pneumoniae, Mycobacterium aurm and Candida albicans. Results of screening assays guided the fractionation of two Rhodophyta, Plocamium corallorhiza and Laurencia flexuosa. The algae were fractionated using silica gel column chromatography and compounds were isolated by semi-preparative normal phase HPLC. Compound characterization was performed using UV, IR and advanced one- and two-dimensional NMR (¹H, ¹³C NMR, COSY, HSQC, HMBC and NOESY) spectroscopy and mass spectrometry. Ten halogenated monoterpenes including four members of the small class of halogenated monoterpene aldehydes were isolated from extracts of P. corallorhiza. The compounds isolated included the known compounds 3,4,6,7-tetrachloro-3,7-dimethyl-1-octene; 4,6-dibromo-1, 1-dichloro-3,7 -dimethyl-2E,7 octadiene; 4,8-d ibromo-1,1,7 -trichloro-3, 7-dimethyl-2,5Eoctadiene;1 ,4,8-tribromo-3, 7 -dichloro-3,7-dimethyl-1 E,5E-octadiene; 8-bremo-6, 7-dichloro-3,7-dimethyl-octa-2E,4E-dienal; 4-Bromo-8-chloro-3,7-dimethyl-octa-2E,6E-dienal; 4,6- Dibromo-3,7-dimethyl-octa-2E,7-dienal; 2,4-dichloro-1-(2-chlorovinyl)-1-methyl-5-methylidene-cyclohexane and two new metabolites 4,8-chloro-3,7-dimethyl-2Z,4,6Z-octatrien-1-al and Compound 3.47. Methodology was developed for the chemical derivatization and mass spectrometric analysis of the aldehydic compounds, The aldehyde trapping reagent 0-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride was used to derivatize the molecules, stabilizing them and allowing for their complete characterization. From Laurencia flexuosa a new cuparene sesquiterpene 4-bremo-2-(5-hydroxy-1,2,2- trimethylcyclopent-3-enyl)-5-methylphenol was isolated along with two geometric isomers of the vinyl acetylene bromofucin , An halogenated monoterpene 3S*,4R*-1-bromo-3,4,8-trichloro-9-dichloromethyl-1-E,5-E,7-Z-octatriene was also isolated but was suspected to be a contaminant and an investigation into its biological source revealed that it originated from Plocamium suhrii. A third alga, Martensia elegans was extracted based on published reports of antimicrobial compounds in related species. A new a-alkyl malate derivative was isolated and characterized. Selected compounds isolated during the course of the study were employed in preliminary assays that tested their ability to inhibit biofilm formation by Pseudomonas aeruginosa. The halogenated monoterpenes isolated from the Plocamium species were the only active compounds. 3S*,4R*-1-bromo-3,4,S-trichloro-g-dichloromethyl-1-E,5-E,7-octatriene from P. suhrii inhibited biofilm formation through antibacterial activity on planktonic cells but could not prevent biofilm formation when employed as a film on the surface of microtitre plate wells. 1,4,8-tribromo-3,7-dichloro-3,7-dimethyl-1E,5E-octadiene and 4,6-dibromo-1,1-dichloro-3,7-dimethyl-2E,7-octadiene inhibited biofilm formation when applied as a film to the microtitre plate wells but had no significant antibacterial activity. No potential antifouling agents were identified in this project but the antimicrobial activity exhibited by the crude algal extracts was highly encouraging and a number of new research areas have been identified. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

Bacterial resistance to antibiotics has been a great problem for many years. The degree of resistance and the speed with which resistance develops varies with different organisms and different drugs. Enzymes called β-lactamases are produced by bacteria and are one mechanism in which bacteria develop antimicrobial resistance. Gram-negative bacteria producing enzymes called ESBLs because of their wide substrate range are of a particular concern in nosocomial infections. In many countries people still use traditional medicine derived from plants as an alternative to the Western medicine due to increased cost of Western medicine and microbial resistance of antibiotic treatments. Biologically active compounds isolated from plants species are used in herbal medicine. Because of the high prevalence of the ESBLs and their increasing resistance to the antibiotics, this research study was done to test the antimicrobial activities of selected medicinal plants of the Eastern Cape; G. incanum, D. angustifolia and E. autumnalis which were traditionally used to treat various infections. The in vitro antimicrobial activity of three different extracts (acetone, methanol & distilled water) and the traditional preparations of the three plants were tested against the selected strains of ESBL-producing bacteria, non β-lactamase producers and the different fungal species. The extracts were screened against 26 Gram-positive bacterial strains, 53 Gram-negative bacterial strains and 15 fungal strains. The Gram-positive bacteria included strains from S. aureus, B. cereus and E. faecalis. The Gram-negative bacteria included strains from E. ii coli, E. cloacae, K. pneumoniae, P. aeruginosa and Acinetobacter spp. The fungal strains included 9 strains of Candida albicans and a single strain of each of the following opportunistic fungi, Mucor sp, Geotrichium sp, Penicillium sp, Fusarium sp and Rhizopus sp. The agar dilution assay was used for the antimicrobial screening of the plants extracts and for the determination of the MICs. The Ames test was performed for the determination of probable carcinogenicity of the extracts of G. incanum and D. angustifolia. The distilled water extracts followed by acetone extracts of the plants revealed the highest antimicrobial activity against the different microbial strains. The extracts of G. incanum followed by the extracts of D. angustifolia inhibited the highest number of microbial strains. The extracts of E. autumnalis did not show any antimicrobial activity against all the pathogens in this study. More of the Gram-positive bacteria were inhibited by the plant extracts. The lowest MIC was obtained with Gram-positive bacteria. The bacterial strains of E. faecalis and P. aeruginosa were not inhibited by any of the plants extracts in the agar dilution assay yet Acinetobacter species which are MDR were inhibited by the distilled water and methanol extracts of G. incanum. A single strain of Mucor sp was the only spore forming fungi that was inhibited by the distilled water extracts of G. incanum. None of the plants extracts showed any mutagenic effects on the TA100 S. typhimurium strains incorporated on the Ames test. Apart from revealing of new antimicrobial agents that may be used against resistant organisms, the proper use of antimicrobial agents should be recommended. The study has highlighted a need for further investigations on the properties of the medicinal plants used in this study.

It has been estimated that between 3000 and 4000 plant species are used for their medicinal properties throughout South Africa, with approximately 27 million South Africans making use of traditional medicines. Of this 27 million, 3 million South Africans rely on traditional medicine as their primary source of health care. Of the 250 000 to 500 000 known plant species, very few have been investigated for their pharmacological qualities, and compounds of significant medicinal value may still remain undiscovered in many plant species. The aims of this study included investigating the antimicrobial properties of Geranium incanum and Artemisia afra, both plants traditionally used for their medicinal properties, and comparing the antimicrobial activity of the latter to that of Artemisia absinthium, as well as investigating the anticancer properties of G. incanum and A. afra, and comparing the anticancer activity of the latter to that of A. absinthium. Infusions, aqueous-, methanol- and acetone extracts of the three plants were prepared and used for anticancer and antimicrobial screening. Plant specimens used to prepare extracts for antimicrobial activity were collected and extracted over three seasons, while extracts used for anticancer screening were prepared from plants collected during the summer only. Considerable variation existed in the percentage crude extract yields obtained when different extractants were used, while the season in which the plants were harvested and extracted also appeared to play a significant role in the amount of extract obtained. The plant extracts were screened for antimicrobial activity against various strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus and Bacillus cereus, using an agar dilution method. G. incanum and A. afra possessed activity for C. albicans, while all three plants showed activity for S. aureus and B. cereus. Activity was largely dependent on the extraction method used. iii The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to screen for anticancer activity of the respective extracts, at varying concentrations, against MCF-7 (human breast adenocarcinoma) cells, HT-29 (human colonic adenocarcinoma) cells and HeLa (human cervical cancer) cells. All of the extracts showed cytotoxic activity in all three cell lines to varying extents, depending on the extract used and cell line screened. The acetone extract of A. afra proved to be the most effective inhibitor with the lowest IC50 (2.65 ± 1.05 μg/ml) having been shown in MCF-7 cells. A. afra and A. absinthium showed similar inhibitory patterns, with the methanol- and acetone extracts having been the most potent inhibitors of each of the respective cell lines in general. Fluorescence microscopy employing 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) and propidium iodide (PI) staining indicated that the acetone extract of A. afra induces apoptosis in MCF-7 cells as apposed to necrosis, and the results were comparable to those obtained for cells exposed to cisplatin. Screening of the A. afra acetone extract for toxicity in normal human cells using the CellTiter-Blue® assay indicated the extract to be toxic to peripheral blood mononuclear cells (PBMC’s) at concentrations comparable to that for MCF-7 cells, while cell cycle analysis of MCF-7 cells exposed to the A. afra acetone extract indicated the extract’s ability to induce apoptosis comparable to that of cisplatin, with the extract exerting its activity at a point during or just prior to the S phase of the cell cycle.

The promotion and development of indigenous knowledge pertaining to the traditional African healing system is one of the prime objectives set out by the South African government. Despite excellent research opportunities and funding, the biggest problem with ethnopharmacological research is a lack of interaction with indigenous communities, which tends to dilute the benefits this research has to offer these communities. The primary aim of this study was thus to promote the traditional African healing system through collaborative medicinal plant research with local traditional health practitioners. The research collaboration aimed to validate some biological activities of traditional remedies used by collaborating traditional health practitioners and ensured interactive sessions where scientific literature, research practices, findings and relevant legislation were discussed and debated. The joint development of a medicinal garden was a valuable tool in realising these goals. Aqueous and ethanol extracts of Bulbine frutescens, Ornithogalum longibracteatum, Ruta graveolens, Tarchonanthus camphoratus and Tulbaghia violacea were selected for antimicrobial, anticancer and anti-diabetic screening, because of their sustainable utilisation potential. The ethanol extract of T. violacea produced the best antimicrobial activity on Bacillus subtilis (100% growth inhibition) and Candida albicans (89% growth inhibition) at 250 μg/ml. The EC50 for the ethanol extract of T. violacea against HT29 colon cancer cells was 101 μg/ml. The aqueous extracts of B. frutescens and T. camphoratus (0.5 and 50 μg/ml) produced the highest overall glucose uptake activity in Chang liver and C2C12 muscle cells. T. camphoratus was unanimously chosen by participating practitioners as the plant to be investigated further. The aqueous extract of T. camphoratus increased glucose uptake in C2C12 muscle cells through increased translocation of GLUT4 to the plasma membrane and activation of the PI3-kinase and AMP-kinase pathways. It produced some alpha-glucosidase inhibitory activity at concentrations of ≥ 200 μg/ml. Apart from interactive feedback seminars at which the findings were presented to participating practitioners, all scientific literature regarding the plants was summarised, translated, compiled and given to participating practitioners in written format. An indigenous knowledge agreement has been negotiated and will formalise the collaboration in future. It is recommended that future research focuses on plants with economic development potential that can be cultivated in the medicinal garden.

M.Sc. (Biochemistry) / A rich diversity of medicinal plants is found in Southern Africa and approximately 80% of the population still relies on medicinal plants to fulfil its primary health care needs. Many of these medicinal plants are used to treat ailments such as burns, sores, urinary tract infections, colds, flu, rheumatism, gout, cancer, hypertension, diabetes, human immunodeficiency virus infections and acquired immunodeficiency syndrome. An example of such a plant is Hypoxis hemerocallidea (Fisch & CA Mey), formerly known as Hypoxis rooperi and popularly known as the African potato, from the Hypoxidaceae family. This plant is found across five of the South African provinces and corm extracts are reported to contain bioactive compounds that account for the plant’s medicinal and therapeutic properties. This study was conducted to investigate the anti-oesophageal cancer and antimicrobial potential of H. hemerocallidea. In cancer patients, the currently used cancer treatments such as radiotherapy and chemotherapy are ineffective in decreasing disease progression, prolonging survival, providing cure and are associated with side-effects such as cytotoxicity to normal body cells and tumour non-specificity. Therefore, current cancer research is aiming at searching for novel plant-based anticancer compounds that can be used for the development and manufacturing of cancer treatment drugs that will have less side-effects and less toxicity towards the normal human body cells, and ultimately provide cure for cancer. In addition to cancer, infectious diseases still contribute to most premature deaths worldwide and are now becoming more difficult to treat due to multidrug resistance developed by pathogens against many of the currently used antibiotics. This multidrug resistance of human pathogens to antibiotics has led to a search for new antimicrobial compounds from plants sources, for use in the production of new affordable antibiotic drugs to effectively treat infections without posing any unwanted toxicity and harm towards the human body. An oesophageal SNO cancer cell line was treated with H. hemerocallidea extracts and the effect of the extracts on the cancer cells were investigated with cell viability assays (trypan blue dye exclusion and AlamarBlue® viability assays), light microscopy and flow cytometrical analysis (forward and side scatter analysis). The plant extracts were also tested for antimicrobial activities against various microorganisms - Gram-positive and Gram-negative bacteria, yeast and fungi cultures by means of thin layer chromatographic bioautography (TLC-DB), microdilution assays and the BacTiter-GloTM assay. Antimicrobial compounds were then putatively identified and characterised using gas chromatography-mass spectrometry (GC-MS). No morphological changes were observed in the SNO cells and significant cell death did not occur following treatment with either water or ethanolic H. hemerocallidea extracts from fresh or dried corms or leaves. The ethanolic leaf extracts did not show any significant inhibition against any of the microorganisms tested in contrast to the ethanolic extracts from the corms, which showed microbial growth inhibition against Gram-positive bacteria and fungi and partial inhibition of the Gram-negative bacteria. The bioactive compounds responsible for the antibacterial and antifungal activities were identified as levoglucosan (as the major antimicrobial compound), pyrocatechol and hexahydro-3-(2-methylpropyl)-pyrrolo[1,2-α]pyrazine-1,4-dione. These results show that H. hemerocallidea plant extracts possessed no anticancer effects towards the SNO cell line. In addition, the corm extracts of H. hemerocallidea contain a levoglucosan compound, which may work synergistically with other antimicrobial compounds to exert antimicrobial properties. With more research, the antimicrobial compounds in H. hemerocallidea may hold promise for possible candidates for use in the development of antibiotic or antiseptic products (for example, topical creams and lozenges) to be used in the treatment of skin and soft tissue infections caused by bacterial and fungal infections.

N-acyl ethanolamines (NAEs) are a class of lipids recently recognized as signaling molecules which are controlled, in part, by their degradation by fatty acid amide hydrolase (FAAH). On the basis of previous studies indicating increased NAE levels in a tobacco cell suspension-xylanase elicitor exposure system and the availability of FAAH mutants, overexpressor and knockout (OE and KO) genotypes in Arabidopsis thaliana, further roles of NAEs in A. thaliana plant defense was investigated. The commonly occurring urban antimicrobial contaminant triclosan (TCS) has been shown to suppress lipid signaling associated with plant defense responses. Thus, a second objective of this study was to determine if TCS exposure specifically interferes with NAE levels. No changes in steady state NAE profiles in A. thaliana-Pseudomonas syringae pv. syringae and A. thaliana-flagellin (bacterial peptide, flg22) challenge systems were seen despite evidence that defense responses were activated in these systems. There was a significant drop in enoyl-ACP reductase (ENR) enzyme activity, which catalyzes the last step in the fatty acid biosynthesis pathway in plants, on exposure of the seedlings to TCS at 10 ppm for 24 h and decreased reactive oxygen species (ROS) production due to flg22 in long term exposure of 0.1 ppm and short term exposure of 5 ppm. However, these responses were not accompanied by significant changes in steady state NAE profiles.