La durabilité du bois de teck (Tectona grandis) est une propriété pouvant varier selon le génotype et les facteurs environnementaux. Chez le teck, le degré d'implication des extractibles dans la durabilité naturelle est controversé. A partir d'une approche quantitative incluant les aspects biologiques et technologiques conduites sur des échantillons de bois séchés à l'air ambiant, cette thèse s'est attachée à rechercher les déterminants chimiques de nature phénolique de la durabilité naturelle. Nous avons tout d'abord mis en évidence que les formes osidiques stockées dans l'aubier sont transformées en extractibles de nature quinonique. Nous avons ainsi caractérisé deux composés, l'un dans l'aubier le forsythoside B, un trisaccharide de l'acide caféique et l'autre dans le duramen, le 4',5'-dihydroxy-épiisocatalponol qui ont été identifiés pour la première fois dans le bois de teck. Nous avons mis en évidence que le second composé inhibe la croissance de Trametes versicolor indiquant son rôle directe dans la propriété de durabilité naturelle du bois de teck. Ainsi, les composés du métabolisme des naphthoquinones sont les plus impliqués dans la durabilité naturelle du bois de teck à l'égard de Trametes versicolor et de Poria placenta. Les mécanismes de transformation des sucres pourraient indiquer le niveau de durabilité naturelle des espèces. Ces nouvelles données contribueront aussi à l'amélioration de la qualité du bois qui par ailleurs assure la pérennité des arbres. / Teak (Tectona grandis) wood natural durability is a property which can vary with genotype and environmental factors. The implication of quinonic extractives in the property of natural durability is controversial. Using a quantitative approach including biological and technological conducted on air-dried wood samples, this thesis aimed to search chemical attributes of natural durability. We first demonstrated that osidic forms stored in the sapwood were transformed into quinone derivative. We have characterized two compounds the forsythoside B, a trisaccharide of cafeic acid in the sapwood and in the heartwood, the 4',5'-dihydroxy(epi)isocatalponol that were identified for the first time in teakwood. The latter compound exhibited strong fungicidal activity against Trametes versicolor indicating that its direct implication in decay resistance of teak wood. We have shown that compounds from naphthoquinones metabolism were involved in decay resistance of teak wood against Trametes versicolor and Poria placenta. The mechanisms of sugars transformation may indicate the natural durability level of sustainable species. There these new data will contribute to improve the wood quality that ensures the perennity of trees.

Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2019 / The agro-processing industry is currently facing losses due to microbial spoilage of agricultural produce and associated value-added products such as beverages. Decay and undesired fermentation of fruit and beverages by fungal, yeast and bacterial spoilage organisms are among the major contributors of product losses in the food industry. When looking at the different level of food spoilage, it is common to find different spoilage organisms occurring in the same food item; which usually requires food producers to utilise a mixture of synthetic preservatives for spoilage organism control. Some of the synthetic chemical compounds with growth inhibition properties that have been used in food preservation are sulphur dioxide, benzoic, lactic, sorbic and acetic acid. These compounds act against a variety of spoilage microorganisms. In post-harvest control of fungi, triazoles, hydroanilide fenhexamid, dicarboximides and succinate dehydrogenase are also being used. Some spoilage organisms have been found to be resistant to the use of synthetic chemical preservatives which usually favour the use of higher dosage of preservatives in food. The use of synthetic chemicals as preservative and as postharvest control agents has been found to present serious health risks such as cardiovascular diseases, muscles and stomach pains, eyesight and skin damages and impairment of brain functions. The problem posed by the current use of synthetic chemicals in food put pressure on food producers and exporters to seek alternatives that will allow for the eradication of the use of synthetic chemicals as preservative in beverages and as postharvest control agents on fruits. Yeasts have been found to have the ability to grow at a faster rate on cheap media and to colonise dried surfaces rapidly. It has also been found that yeasts produce extracellular compounds of proteinaceous and volatile organic nature with growth inhibition properties against spoilage organisms. The current findings lack some engineering concept that could assist in the design of a production system for high scale production of biopreservation compounds from yeasts. The availability of a cost effective production media, the growth and production kinetics data using a cheaply available nutrient sources as well as the biological thermodynamic data are some of the gaps in biopreservation bioprospecting. Although several yeasts have already been studied to have great inhibition properties against fruit fungal pathogens, it was still unclear what was the minimum inoculum dose to be able to have a fungistatic and fungicidal effect on the growth of fruit spoilage organisms. The concept of combination of biopreservatives and the interaction effect of their biopreservation activity against consortia of spoilage organisms has also been lacking. As an attempt to seek alternatives to the use of synthetic chemicals as preservatives or postharvest control agents, Candida pyralidae Y1117, Pichia kluyveri Y1125 and Pichia kluyveri Y1164 strains were assessed for antimicrobial activity against spoilage yeasts (Dekkera bruxellensis, Dekkera anomala, Zygosaccharomyces bailii) and spoilage fungi (Botrytis cinerea, Colletotrichum acutatum and Rhizopus stolonifer). As alternative to refined media, a cost effective approach was explored whereby the use of agro-waste, i.e. grape pomace extracts (GPE), as production medium for biopreservation compounds, was studied. Production kinetics using modified existing models, subsequent to optimization using response surface methodology (RSM) for biopreservation compounds production was studied for the three biocontrol yeasts using GPE broth as the fermentation medium. The evaluation of the interaction study between mixtures of crude biopreservatives against consortia of common spoilage organisms present in beverages was also conducted by producing the crude biopreservation compounds separately from yeasts and then formulating growth inhibition combinations (GICs); GIC 1 (Candida pyralidae Y1117 and Pichia kluyveri Y1125); GIC 2 (C. pyralidae Y1117 and P. kluyveri Y1164), GIC 3 (P. kluyveri Y1125 and Pichia kluyveri Y1164); GIC 4 (C. pyralidae, P. kluyveri Y1125 and P. kluyveri Y1164). The spoilage organism consortia combinations, i.e. SC1, D. anomala and D. bruxellensis; SC2 (D. anomala and Z. bailii); SC3 (D. bruxellensis and Z. bailii) and SC4 (D. anomala, D. bruxellensis and Z. bailii) were also prepared. This study also investigated the effect of varying inoculum dose (ID) of Candida pyralidae strain Y1117, Pichia kluyveri Y1125 and Pichia kluyveri Y1164 on the biocontrol of Botrytis cinerea by contaminating the headspace of the growth medium with a fungal plug subsequent to biotreatment with different initial inoculum dose of the respective biocontrol yeasts. Finally, grape pomace extracts was used as fermentation medium to study the biological thermodynamics of biopreservation compound production from the three biocontrol yeasts. The results obtained demonstrated some interesting results. The antagonistic properties of C. pyralidae and P. kluyveri were observed on cheap solidified medium (grape pomace extracts) as well as on fruits (grapes and apples). These yeasts produced extracellular volatile organic compounds (VOCs) that could be responsible for yeast and fungal growth inhibition. Twenty-five VOCs in the category of alcohols, organic acids and esters were identified by GC-MS. The results of the kinetic study showed that the highest volumetric zone of inhibition (VZI) was 1.24 L contaminated solidified media (CSM) per mL biopreservation compounds used (BCU) when Candida pyralidae Y1117 was inoculated in a pH 3-diluted GPE broth (150 g L−1) incubated at 25 °C for 24 h. Similar conditions were applied for Pichia kluyveri Y1125 and P. kluyveri Y1164, albeit under slightly elongated fermentation periods (up to 28 h), prior to the attainment of a maximum VZI of only 0.72 and 0.76 L CSM mL−1 ACU, respectively. The potential biopreservation compounds produced were identified to be isoamyl acetate, isoamyl alcohol, 2-phenyl ethylacetate and 2-phenyl ethanol. The growth inhibition interaction study showed a variation in growth inhibition proficiency depending on the spoilage organisms or the consortia of spoilage organisms being deactivated. It was then suggested that, a food environment contaminated with a consortium of spoilage organisms can be controlled by employing either the crude biopreservation compounds from individual yeast or those of the following yeast combinations, GIC1-4, which showed a better growth inhibition proficiency against SC1-3. The fungistatic and fungicidal effects on the fungal pathogen were dose dependent. The fungistatic characteristics against Botrytis cinerea were displayed after 7 days when 102-105 cells mL-1 of Candida pyralidae Y1117, Pichia kluyveri Y1125 and Pichia kluyveri Y1164 were independently used in-vitro and in-vivo. However, 106-108 cells mL-1 inoculum doses displayed fungicidal characteristics. Additionally, the fungicidal property of yeasts studied was also confirmed on table grape (in vivo studies) using closed jar method. The biological thermodynamic study showed that, dried biomass molecular weight of 28.9 g/C-mol, 29.163 g/C-mol, and 27.176 g/C-mol were obtained for Candida pyralidae strain Y1117, Pichia kluyveri Y1125 and Pichia kluyveri Y1164 respectively. The results obtained successfully established useful biological thermodynamic data applicable to the design of adequate biopreservatives production system from yeasts using cheaply available nutrients source.

No description available.

A pele e as mucosas constituem as primeiras barreiras na defesa contra infecções e os macrófagos são componentes essenciais do sistema imune inato, importante neste aspecto. O envolvimento destas células pode ser verificado em grande percentual das imunodeficiências primárias. Desta forma, a avaliação da função fagocitária é de extrema relevância para o reconhecimento dos distúrbios imunológicos que acometem a pele. O objetivo do presente estudo foi avaliar a metodologia laboratorial para a detecção de defeitos funcionais dos fagócitos. Para isto foram estabelecidos os seguintes testes laboratoriais: Nitro Blue Tetrazolium (NBT), Dihidrorodamina (DHR), quimiotaxia, fagocitose e a aderência de S. aureus e C. albicans por citometria de fluxo (CF), além de morte intracelular de S. aureus e C. albicans (CF). Para verificar a integridade do sistema complemento realizou-se ensaios hemolíticos para as vias clássica e alternativa (CH50 e AP50). A metodologia proposta foi aplicada em indivíduos normais para a padronização dos testes. O burst oxidativo avaliado pelo teste da dihidrorodamina (DHR) foi aplicado em 101 indivíduos saudáveis e em paralelo, 50 indivíduos sadios para o teste do NBT. Os mesmos testes foram realizados em pacientes com Candidíase mucocutânea crônica (CMC) (n=9 ), Candidíase persistente (n=5), Suspeita de distúrbios de fagócitos (SDF) (n=14), Doença Granulomatosa Crônica (DGC)(n= 7) e portadores de DGC (n=5). A quimiotaxia foi padronizada em 34 controles para neutrófilos estimulados com Lipopolissacarídeo de E.Coli (LPS) e 5 com fungo Candida albicans. A técnica de fagocitose e aderência de patógenos foi padronizada com os mesmos estímulos (n=7 para fungos/n=5 para bactéria). Após a padronização, o ensaio foi aplicado em pacientes com candidíase persistente (n=5 para bactéria e n=5 para fungo) e em pacientes com CMC (n= 3 para bactéria e n=4 para fungo). Os ensaios de fagocitose e morte intracelular (capacidade bactericida e fungicida) foram padronizados em 18 indivíduos sadios para bactérias e os ensaios de morte intracelular para S. aureus foi aplicado em pacientes com CMC (n=5), com CP (n=6), com SDF (n =9) e com DGC (n=2), para os ensaios de fagocitose com morte intracelular para fungos foram utilizados 22 indivíduos saudáveis e após a padronização do ensaio foram aplicados em pacientes com CMC (n=8), pacientes com CP ( n= 7), pacientes com DGC (n=2) e indivíduos com SDF (n= 13) O ensaio de DHR foi padronizado e estabelecido em 80% de intensidade de fluorescência para células estimuladas com PMA e 15% de intensidade de fluorescência para células sem estímulo. Nos resultados do DHR encontrou-se diferença significativa no grupo de DGC (n=7)(P= 0,0001), no grupo de portadores (n=5)(P=0,0005) e no grupo de SDF (n=14)(P= 0,0053). O ensaio do DHR foi repetido após 24 horas da coleta (n=7), não se verificando alteração da resposta. A quimiotaxia mostrou diferença significativa entre C (n=4) vs SDF (n=3)(P=0,0001) e pacientes com CMC apresentaram redução da capacidade quimiotática para bactérias (n=3)e fungos (n= 4) com soro autólogo (P= 0,0246 e P=0,0109, respectivamente). Na fagocitose e aderência de bactérias inativadas ,os grupos de CMC, CP E SDF não mostraram diferenças significativas com bactérias não opsonizadas ou opsonizadas com soro AB e apresentaram menor índice de fagocitose (C x CMC)(P=0,0357) quando foram opsonizadas com soro autólogo. Na fagocitose e aderência de fungos inativados, controles e grupos de pacientes apresentaram resposta semelhante com fagocitose preservada. Os ensaios de morte intracelular para bactérias não opsonizadas houve menor expressão de fagocitose no grupo de C x SDF (P=0,0044). Na capacidade bactericida verificou-se diferença significativa entre os grupos CxCMC (P=0,0403). A opsonização das bactérias com soro AB foi significativamente diferente entre os grupos CxCP (P=0,0129) e CxSDF (P=0,0048) e com capacidade bactericida diferente entre grupos CxCP (P=0,0258) e CxSDF (P=0,0205). Na avaliação da fagocitose de bactérias opsonizadas com soro autólogo foi verificada diferença significativa entre os grupos CxCP (P=0,0013) e CxSDF (P=0,0048). Não houve diferença na capacidade bactericida dos grupos de pacientes com o controle. Os ensaios de fagocitose e morte intracelular para fungos sem opsonização não mostrou diferença estatisticamente significativa. A morte intracelular mostrou-se diferente para o grupo CxCMC (P=0,0155) e quando opsonizado com soro AB houve diferença CxCP (P=0,0369). A fagocitose com opsonização por soro autólogo significativa no grupo CxSDF (P=0,0001) e um paciente de CMC com sua fagocitose comprometida quando comparado com o controle do dia. A morte intracelular foi diferente nos grupos CxCMC (P=0,0018) e CxCP (p=0,0203). Não houve diferença estatisticamente significativa à avaliação do complemento. O ensaio do DHR mostrou ser sensível e preciso para o diagnóstico de DGC e portadores de DGC, porém pode detectar outras alterações de fagócitos. O ensaio de aderência e fagocitose mostraram-se variáveis dificultando a padronização de valores de normalidade e exclusão de defeitos. Ensaios de fagocitose com morte intracelular mostraram-se como a melhor forma de detectar distúrbios de fagócitos além do diagnóstico de DGC. A aplicação de controles do dia mostrou-se necessária e importante para a detecção de defeitos funcionais. O presente trabalho mostrou que a avaliação de distúrbios de fagócitos por morte intracelular por citometria de fluxo pode ser aplicado em outras situações clínicas com comprometimento imunológico / Skin and mucosa are part of the first barriers in the defense against infections, and the macrophages are essential components of the innate immune system, important when related to this aspect. The involvement of these cells can be seen in a large percentage of the primary immunodeficiencies. Therefore, the assessment of the phagocitary function is extremely important for the recognition of immunological disorders which affect the skin. The present study focus on the evaluation of the laboratorial methodology for the detection of functional defects of phagocytes. For this the following laboratorial tests were established: Nitro Blue Tetrazolium (NBT), chemotaxis, phagocytosis and adherence of S. aureus and C. albicans through flow cytometry (FC), besides the intracellular death of S. aureus and C. albicans (FC). To assess the integrity of the complement system hemolytic assays were performed for the classic and alternative pathways (CH50 and AP50). The proposed methodology was applied to normal individuals for the standardization of the assays. The oxidative burst evaluated through the dihydrorodamine essay (DHR) was applied to 101 healthy individuals and in parallel, 50 healthy individuals for the NBT assay. The same assays were performed on patients with Chronic mucocutaneous candidiasis (CMC)(n=9), persistent candidiasis (n=5), Phagocytes disorders suspicious (PDS) (n=14), Chronicle granulomatous disease (CGD)(n=7) and CGD carriers (n=5). Chemotaxis was standardized using 34 controls for neutrophils stimulated by lipopolisacharydes from e. coli (LPS) and 5 by C. albicans. Phagocytosis and adherence of pathogens were standardized using the same stimuli (n=7 for fungi and n=5 for bacteria). Following the standardization, the assay was applied to patients with persistent candidiasis (n=5 for fungi and n=5 for bacteria) and on patients with CMC (n=4 for fungi and n=3 for bacteria). Phagocytosis and intracellular death assays (bactericidal and fungicidal capacity) were standardized using 18 healthy individuals for bacteria and the intracellular death assays for S. aureus were applied on patients suffering from CMC (n=5), from PC (n=6), from PDS (n=9) and from CGD (n=2), for the phagocytosis with fungi intracellular death assays 22 healthy individuals were used, and following the standardization the assay was applied to patients suffering from CMC (n=8), from PC (n=7), from CGD (n=2) and PDS individuals (n=13). The DHR assay was standardized and established according to fluorescence intensity 80% for cells stimulated by PMA and fluorescence intensity 15% for cells without stimuli. In the DHR results a significant difference in the CGD group (n=7)(P= 0,0001), in the carriers group (n=5)(P=0,0005) and in the PDS group (n=14)(P= 0,0053) was found. The DHR assay was performed once again 24 hours after the sample collection (n=7) and no changes in the response were seen. Chemotaxis showed a significant difference between C (n=4) vs PDS (n=3)(P=0,0001) and patients suffering from CMC showed decreased ability in the chemotaxis of bacteria (n=3) and fungi (n=4) with autologous serum (P= 0,0246 e P=0,0109, respectively). In the phagocytosis and adherence of inactivated bacteria, the CMC, PC and PDS groups showed no significant differences with non-opsonizated bacteria or opsonizated with AB serum and presented a lower phagocytosis level (C x CMC)(P=0,0357) when they were opsonizated by autologous serum. In the phagocytosis and adherence of inactivated fungi, controls and patient groups presented a similar response with preserved phagocytosis. In the intracellular death assays for non-opsonizated bacteria there was a lower phagocytosis expression in the C x SDF group (P=0,0044). In the bactericidal ability a significant difference between the groups C x CMC was seen (P=0,0403). The opsonization of bacteria with AB serum showed a significant difference among the groups C x CP (P=0,0129) and C x SDF (P=0,0048) and with different bactericidal ability among the groups C x CP (P=0,0258) and C x SDF (P=0,0205). In the evaluation of the phagocytosis of bacteria opsonizated by autologous serum a significant difference among the groups C x CP (P=0,0013) and C x SDF (P=0,0048) was seen. There was no difference between the bactericidal ability of the patients group and control group. The phagocytosis and intracellular assays for fungi without opsonization presented no significant statistical difference. Intracellular death was different for the C x CMC group (P=0,0155) and when opsonizated by AB serum difference was shown C x CP (P=0,0369). The phagocytosis with opsonization by autologous serum presented significant difference in the C x SDF group (P=0,0001) and in a CMC patient with compromised phagocytosis when compared with the daily control. Intracellular death was different in the C x CMC (P=0,0018) and C x CP (p=0,0203) groups. There was no significant statistical difference according to the complement evaluation. The DHR assay was seen as very sensitive and precise for the diagnosis of CGD, however it can detect other phagocyte alterations. The phagocytosis and adherence assay varied a lot making the standardization of normal values and defects exclusion very difficult. Phagocytosis with intracellular death assays showed the best performance to detect phagocytes disorders besides CGD diagnosis. The use of daily controls was seen as very necessary and important to detect functional disorders. This study demonstrated that phagocytes disorder evaluation through intracellular death using flow cytometry can be applied to other clinical situations which are immunologically compromised

A pele e as mucosas constituem as primeiras barreiras na defesa contra infecções e os macrófagos são componentes essenciais do sistema imune inato, importante neste aspecto. O envolvimento destas células pode ser verificado em grande percentual das imunodeficiências primárias. Desta forma, a avaliação da função fagocitária é de extrema relevância para o reconhecimento dos distúrbios imunológicos que acometem a pele. O objetivo do presente estudo foi avaliar a metodologia laboratorial para a detecção de defeitos funcionais dos fagócitos. Para isto foram estabelecidos os seguintes testes laboratoriais: Nitro Blue Tetrazolium (NBT), Dihidrorodamina (DHR), quimiotaxia, fagocitose e a aderência de S. aureus e C. albicans por citometria de fluxo (CF), além de morte intracelular de S. aureus e C. albicans (CF). Para verificar a integridade do sistema complemento realizou-se ensaios hemolíticos para as vias clássica e alternativa (CH50 e AP50). A metodologia proposta foi aplicada em indivíduos normais para a padronização dos testes. O burst oxidativo avaliado pelo teste da dihidrorodamina (DHR) foi aplicado em 101 indivíduos saudáveis e em paralelo, 50 indivíduos sadios para o teste do NBT. Os mesmos testes foram realizados em pacientes com Candidíase mucocutânea crônica (CMC) (n=9 ), Candidíase persistente (n=5), Suspeita de distúrbios de fagócitos (SDF) (n=14), Doença Granulomatosa Crônica (DGC)(n= 7) e portadores de DGC (n=5). A quimiotaxia foi padronizada em 34 controles para neutrófilos estimulados com Lipopolissacarídeo de E.Coli (LPS) e 5 com fungo Candida albicans. A técnica de fagocitose e aderência de patógenos foi padronizada com os mesmos estímulos (n=7 para fungos/n=5 para bactéria). Após a padronização, o ensaio foi aplicado em pacientes com candidíase persistente (n=5 para bactéria e n=5 para fungo) e em pacientes com CMC (n= 3 para bactéria e n=4 para fungo). Os ensaios de fagocitose e morte intracelular (capacidade bactericida e fungicida) foram padronizados em 18 indivíduos sadios para bactérias e os ensaios de morte intracelular para S. aureus foi aplicado em pacientes com CMC (n=5), com CP (n=6), com SDF (n =9) e com DGC (n=2), para os ensaios de fagocitose com morte intracelular para fungos foram utilizados 22 indivíduos saudáveis e após a padronização do ensaio foram aplicados em pacientes com CMC (n=8), pacientes com CP ( n= 7), pacientes com DGC (n=2) e indivíduos com SDF (n= 13) O ensaio de DHR foi padronizado e estabelecido em 80% de intensidade de fluorescência para células estimuladas com PMA e 15% de intensidade de fluorescência para células sem estímulo. Nos resultados do DHR encontrou-se diferença significativa no grupo de DGC (n=7)(P= 0,0001), no grupo de portadores (n=5)(P=0,0005) e no grupo de SDF (n=14)(P= 0,0053). O ensaio do DHR foi repetido após 24 horas da coleta (n=7), não se verificando alteração da resposta. A quimiotaxia mostrou diferença significativa entre C (n=4) vs SDF (n=3)(P=0,0001) e pacientes com CMC apresentaram redução da capacidade quimiotática para bactérias (n=3)e fungos (n= 4) com soro autólogo (P= 0,0246 e P=0,0109, respectivamente). Na fagocitose e aderência de bactérias inativadas ,os grupos de CMC, CP E SDF não mostraram diferenças significativas com bactérias não opsonizadas ou opsonizadas com soro AB e apresentaram menor índice de fagocitose (C x CMC)(P=0,0357) quando foram opsonizadas com soro autólogo. Na fagocitose e aderência de fungos inativados, controles e grupos de pacientes apresentaram resposta semelhante com fagocitose preservada. Os ensaios de morte intracelular para bactérias não opsonizadas houve menor expressão de fagocitose no grupo de C x SDF (P=0,0044). Na capacidade bactericida verificou-se diferença significativa entre os grupos CxCMC (P=0,0403). A opsonização das bactérias com soro AB foi significativamente diferente entre os grupos CxCP (P=0,0129) e CxSDF (P=0,0048) e com capacidade bactericida diferente entre grupos CxCP (P=0,0258) e CxSDF (P=0,0205). Na avaliação da fagocitose de bactérias opsonizadas com soro autólogo foi verificada diferença significativa entre os grupos CxCP (P=0,0013) e CxSDF (P=0,0048). Não houve diferença na capacidade bactericida dos grupos de pacientes com o controle. Os ensaios de fagocitose e morte intracelular para fungos sem opsonização não mostrou diferença estatisticamente significativa. A morte intracelular mostrou-se diferente para o grupo CxCMC (P=0,0155) e quando opsonizado com soro AB houve diferença CxCP (P=0,0369). A fagocitose com opsonização por soro autólogo significativa no grupo CxSDF (P=0,0001) e um paciente de CMC com sua fagocitose comprometida quando comparado com o controle do dia. A morte intracelular foi diferente nos grupos CxCMC (P=0,0018) e CxCP (p=0,0203). Não houve diferença estatisticamente significativa à avaliação do complemento. O ensaio do DHR mostrou ser sensível e preciso para o diagnóstico de DGC e portadores de DGC, porém pode detectar outras alterações de fagócitos. O ensaio de aderência e fagocitose mostraram-se variáveis dificultando a padronização de valores de normalidade e exclusão de defeitos. Ensaios de fagocitose com morte intracelular mostraram-se como a melhor forma de detectar distúrbios de fagócitos além do diagnóstico de DGC. A aplicação de controles do dia mostrou-se necessária e importante para a detecção de defeitos funcionais. O presente trabalho mostrou que a avaliação de distúrbios de fagócitos por morte intracelular por citometria de fluxo pode ser aplicado em outras situações clínicas com comprometimento imunológico / Skin and mucosa are part of the first barriers in the defense against infections, and the macrophages are essential components of the innate immune system, important when related to this aspect. The involvement of these cells can be seen in a large percentage of the primary immunodeficiencies. Therefore, the assessment of the phagocitary function is extremely important for the recognition of immunological disorders which affect the skin. The present study focus on the evaluation of the laboratorial methodology for the detection of functional defects of phagocytes. For this the following laboratorial tests were established: Nitro Blue Tetrazolium (NBT), chemotaxis, phagocytosis and adherence of S. aureus and C. albicans through flow cytometry (FC), besides the intracellular death of S. aureus and C. albicans (FC). To assess the integrity of the complement system hemolytic assays were performed for the classic and alternative pathways (CH50 and AP50). The proposed methodology was applied to normal individuals for the standardization of the assays. The oxidative burst evaluated through the dihydrorodamine essay (DHR) was applied to 101 healthy individuals and in parallel, 50 healthy individuals for the NBT assay. The same assays were performed on patients with Chronic mucocutaneous candidiasis (CMC)(n=9), persistent candidiasis (n=5), Phagocytes disorders suspicious (PDS) (n=14), Chronicle granulomatous disease (CGD)(n=7) and CGD carriers (n=5). Chemotaxis was standardized using 34 controls for neutrophils stimulated by lipopolisacharydes from e. coli (LPS) and 5 by C. albicans. Phagocytosis and adherence of pathogens were standardized using the same stimuli (n=7 for fungi and n=5 for bacteria). Following the standardization, the assay was applied to patients with persistent candidiasis (n=5 for fungi and n=5 for bacteria) and on patients with CMC (n=4 for fungi and n=3 for bacteria). Phagocytosis and intracellular death assays (bactericidal and fungicidal capacity) were standardized using 18 healthy individuals for bacteria and the intracellular death assays for S. aureus were applied on patients suffering from CMC (n=5), from PC (n=6), from PDS (n=9) and from CGD (n=2), for the phagocytosis with fungi intracellular death assays 22 healthy individuals were used, and following the standardization the assay was applied to patients suffering from CMC (n=8), from PC (n=7), from CGD (n=2) and PDS individuals (n=13). The DHR assay was standardized and established according to fluorescence intensity 80% for cells stimulated by PMA and fluorescence intensity 15% for cells without stimuli. In the DHR results a significant difference in the CGD group (n=7)(P= 0,0001), in the carriers group (n=5)(P=0,0005) and in the PDS group (n=14)(P= 0,0053) was found. The DHR assay was performed once again 24 hours after the sample collection (n=7) and no changes in the response were seen. Chemotaxis showed a significant difference between C (n=4) vs PDS (n=3)(P=0,0001) and patients suffering from CMC showed decreased ability in the chemotaxis of bacteria (n=3) and fungi (n=4) with autologous serum (P= 0,0246 e P=0,0109, respectively). In the phagocytosis and adherence of inactivated bacteria, the CMC, PC and PDS groups showed no significant differences with non-opsonizated bacteria or opsonizated with AB serum and presented a lower phagocytosis level (C x CMC)(P=0,0357) when they were opsonizated by autologous serum. In the phagocytosis and adherence of inactivated fungi, controls and patient groups presented a similar response with preserved phagocytosis. In the intracellular death assays for non-opsonizated bacteria there was a lower phagocytosis expression in the C x SDF group (P=0,0044). In the bactericidal ability a significant difference between the groups C x CMC was seen (P=0,0403). The opsonization of bacteria with AB serum showed a significant difference among the groups C x CP (P=0,0129) and C x SDF (P=0,0048) and with different bactericidal ability among the groups C x CP (P=0,0258) and C x SDF (P=0,0205). In the evaluation of the phagocytosis of bacteria opsonizated by autologous serum a significant difference among the groups C x CP (P=0,0013) and C x SDF (P=0,0048) was seen. There was no difference between the bactericidal ability of the patients group and control group. The phagocytosis and intracellular assays for fungi without opsonization presented no significant statistical difference. Intracellular death was different for the C x CMC group (P=0,0155) and when opsonizated by AB serum difference was shown C x CP (P=0,0369). The phagocytosis with opsonization by autologous serum presented significant difference in the C x SDF group (P=0,0001) and in a CMC patient with compromised phagocytosis when compared with the daily control. Intracellular death was different in the C x CMC (P=0,0018) and C x CP (p=0,0203) groups. There was no significant statistical difference according to the complement evaluation. The DHR assay was seen as very sensitive and precise for the diagnosis of CGD, however it can detect other phagocyte alterations. The phagocytosis and adherence assay varied a lot making the standardization of normal values and defects exclusion very difficult. Phagocytosis with intracellular death assays showed the best performance to detect phagocytes disorders besides CGD diagnosis. The use of daily controls was seen as very necessary and important to detect functional disorders. This study demonstrated that phagocytes disorder evaluation through intracellular death using flow cytometry can be applied to other clinical situations which are immunologically compromised

PhD (Department of Biotechnology, Faculty of Applied and Computer Sciences), Vaal Universtiy of Technology / The genus Tulbaghia has been used in traditional medicine to treat various ailments such as fever, earache, tuberculosis and esophageal cancer. However, there is limited scientific evidence to support its use. Therefore the objectives of this study were to perform phytochemical analysis, investigate the antioxidant, antimicrobial, anticancer, immunomodulatory activities and toxicity of crude acetone and water extracts from selected Tulbaghia species. Standard methods were used for preliminary phytochemical analysis. The total phenolic content of the plant extracts was determined using the folin ciocalteu method whereas the total flavonoids were determined by using the aluminium chloride colorimetric method. DPPH and ABTS assays were used to evaluate the antioxidant activity. The antimicrobial activity was assessed by agar well diffusion, microtiter dilution and time kill assays. For anticancer studies, the antiproliferative activity of the extracts was evaluated using the MTT assay on Hkesc-1 and KB cells. Morphological changes of the cancer cells treated with extracts were examined using light microscopy. Induction of apoptosis was assessed using fluorescence microscopy and acridine orange/ethidium bromide staining. Flow cytometry analysis was conducted to examine the multicaspase activity and cell cycle arrest. For immunomodulatory activity, the Greiss reagent and Luminex cytokine assays were used to determine the effect of the extracts on NO production and the concentration of the cytokines in the treated cells, respectively. Toxicity of selected Tulbaghia species was examined by investigating the effect of the extracts on the metabolic activity and cell membrane integrity on the treated RAW264.7 cells using the MTT and LDH assays, respectively. The zebrafish assay was used to evaluate the embryotoxicity and teratogenic effects of crude acetone and water extracts of T. violacea at 24 h intervals for 96 h post fertilisation (hpf). The percentage mortality, hatchability and heart rate were examined. Phytochemical screening of eight Tulbaghia species demonstrated the presence of flavonoids, glycosides, tannins, terpenoids, saponins and steroids. The amount of total phenol and flavonoid content varied in different plant extracts ranging from 4.50 to 11.10 milligrams gallic acid equivalent per gram (mg GAE/g) of fresh material and 3.04 to 9.65 milligrams quercetin equivalent per gram (mg QE/g) of fresh material respectively. The IC50 values based on DPPH and ABTS for T. alliacea (0.06 and 0.06 mg/mL) and T. violacea (0.08 and 0.03 mg/mL) were generally lower showing potential antioxidant activities. For antimicrobial activity, the acetone extracts of T. acutiloba, T. alliacea, T. leucantha, T. ludwigiana, T. natalensis and T. simmleri showed moderate antimicrobial activity against all test organisms while the water extracts showed moderate to no activity. One species, T. cernua, showed poor activity against all the tested microbes. The acetone and water extracts of T. violacea showed the greatest antibacterial and antifungal activity against all the tested microorganisms with minimum inhibitory concentration ranging from 0.1 mg/mL to 3.13 mg/mL. The acetone extracts of T. violacea also exhibited both bacteriostatic/fungistatic and bactericidal/fungicidal activity depending on the incubation time and concentration of the extract. The bactericidal/fungicidal activity was observed at x2 MIC. The results for anticancer activity showed that treatment of Hkesc-1 cells with acetone and water crude extracts had anti-proliferative activity with IC50 values of 0.4 mg/mL and 1.625 mg/mL, respectively while KB had 0.2 mg/mL and 1 mg/mL, respectively. Morphological changes such as blebbing, cell shrinkage and rounding were observed in the treated cells suggesting that apoptosis was taking place. AOEB staining showed that the level of apoptosis was dependent on the concentration of the extracts. The activation of multicaspase activity in both Hkesc-1 and KB treated cells was also concentration dependent leading to cell death by apoptosis and the induction of cell cycle arrest at the G2/M phase. Immunomodulatory activity results indicated that cell viability was above 80% when concentrations of 50 µg/mL or less of both acetone and water crude was used. Treatment with the acetone extract had no significant effect (p>0.05) on the LPS induced NO production in RAW264.7 cells except at 50 µg/mL where significant inhibition was observed. The water extract had no significant effect (p>0.05) on NO production at all the concentrations. Treatment of LPS–induced RAW264.7 cells with acetone extract stimulated the production of IL-1α, IL-6 and TNF-α, but had no significant effect (p > 0.05) on IL-1β. On the other hand, treatment with the water extracts stimulated the production of IL-1α, IL-6 but had no significant effect (p>0.05) on TNF-α and IL-1β. Treatment of LPS-induced RAW264.7 cells with the acetone extract had very little stimulatory effect on IL-4, IL-5 and IL-13 and no significant effect on IL-10 whereas for the water extract a significant stimulatory effect was only observed for IL-4 after 48 h of treatment. High concentrations (>10000 pg/mL) of MCP-1, MIP1-α, MIP1-β, MIP-2, GCSF, GM-CSF, RANTES and IP-10 were also observed in acetone and water extract treated RAW264.7 cells. For toxicity studies, acetone and aqueous crude leaf extracts from T. alliacea, T. simmleri, and T. violacea had a significant inhibitory (p<0.05) effect on the RAW264.7 cells after 48h treatment. Acetone extracts from T. alliacea, T. simmleri and T. violacea resulted in IC50 values of 0.48 mg/mL, 0.72 mg/mL and 0.1 mg/mL, respectively. Treatment with water extracts showed minimal toxic effect indicated by higher IC50 values of 0.95 mg/mL, 2.49 mg/mL and 0.3 mg/mL for T. alliacea, T. simmleri and T. violacea, respectively. The LDH release by macrophages after 24 h treatment with acetone extracts was observed to be concentration dependent while treatment with water extracts did not induce LDH release. The zebra fish assay showed a lethal dose (LD50) for the T. violacea acetone crude extract of 20 μg/mL whereas that for water extract was 85 μg/mL. The observed teratogenic effects included scoliosis, edema of the pericardial cavity, retarded yolk resorption, hook-like/bent tail and shorter body length. In conclusion, the results from this study indicate that the extracts from the eight Tulbaghia species examined contain phytochemicals that may have the antioxidant, antimicrobial, anticancer and immunomodulatory properties. Extracts from T. violacea were observed to be the most potent. This study thus supports the use of T. violacea in treating bacterial and fungal infections in traditional medicine. The results of this study also confirm the anticancer potential of T. violacea. The immunomodulatory activity of the acetone and water extracts from T. violacea indicated a dominantly pro-inflammatory activity. Traditional medicine prepared form T. violacea may be of benefit to individuals with weak immune systems. The toxicity of selected Tulbaghia species was observed to be concentration, extract and time dependent. Therefore, traditional medicine prepared from Tulbaghia extracts should be taken with caution preferably in small doses over a short period of time. Future studies will focus on the identification of the bioactive compound(s) responsible for the antimicrobial, anticancer and immunomodulatory activities.