O Brasil é um dos países com maior biodiversidade mundial, porém, poucas espécies vegetais tiveram suas propriedades avaliadas. Os óleos essenciais são compostos voláteis produzidos pelas plantas que contribuem para a sua adaptação ao meio ambiente. Estudos que ampliem o conhecimento sobre o potencial tóxico de plantas medicinais são extremamente relevantes, permitindo que se avalie a segurança do seu uso. Os óleos essenciais da parte aérea de cinco espécies de Aloysia nativas no Rio Grande do Sul e uma cultivada foram obtidos por hidrodestilação em aparelho do tipo Clevenger e a composição química foi determinada por cromatografia gasosa acoplada ao espectrômetro de massas. As espécies que apresentaram 1.8-cineol como composto majoritário foram Aloysia dusenii (16.2%), A. citrodora (32.8%) e A. lycioides coletada em Guaiba (49.5%) e São Marcos (17.6%). A espécie A. polygalifolia e A. virgata tiveram maiores proporções de germacreno-D (11.2% e 12%, respectivamente) e A. chamaedryfolia apresentou espatulenol (15.6%). A espécie A. lycioides coletada em Rosário do Sul teve β-felandreno (23.7%) como o composto principal. Para as espécies A. citrodora, A. lycioides e A. dusenii também se avaliou a toxicidade dos seus óleos essenciais através do teste de letalidade frente a Artemia salina. Para as mesmas espécies, mas nas soluções 1%, 10% e óleo puro (v/v) também se testou os efeitos dos óleos essenciais sobre a germinação e o desenvolvimento inicial de Allium cepa (cebola). No bioensaio de A. salina observouse 100% de letalidade nas concentrações 1000 μg/mL e 500 μg/mL para as três espécies avaliadas. Nas demais concentrações avaliadas o grau de letalidade foi diretamente proporcional à concentração dos mesmos. O LC50 para A. citrodora foi de 55.96 μg/mL, para A. lycioides 48.12 μg/mL e A. dusenii o LC50 foi de 48.98 μg/mL. As espécies possuem composição química distinta o que resulta em respostas citotóxicas diversas. Os valores encontrados no LC50 para os óleos testados são considerados extremamente tóxicos. Os óleos voláteis de A. citrodora, A. lycioides e A. dusenii também apresentaram efeito inibitório sobre o tempo médio de germinação e sobre o crescimento inicial de A. cepa. Ainda, observou-se efeito inibitório significativo desses óleos essenciais sobre a atividade mitótica e metafásica na cebola. Os voláteis também induziram a ocorrência de anormalidades cromossômicas, como cromossomos não-orientados na metáfase, aderências, c-mitoses, micronúcleos e brotos nucleares. O óleo essencial de A. citrodora demonstrou ser o mais tóxico entre as espécies avaliadas. O presente estudo sugere que os compostos majoritários e minoritários das espécies de Aloysia têm ação sinérgica resultando nos efeitos observados, tanto para a atividade citotóxica como genotóxica. Esse trabalho contribuiu significativamente para ampliar os conhecimentos sobre a diversidade e composição química dos voláteis das espécies de Aloysia do RS e também para o entendimento do modo de ação dos produtos naturais com potencial alelopático e a relação ecológica entre as espécies, além de reportar sobre a toxicidade do óleo essencial dessas espécies que são muito utilizadas pela medicina popular. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2017-03-07T14:03:33Z No. of bitstreams: 1 Dissertacao Eluíza Thomas.pdf: 2451474 bytes, checksum: bb0c2710663f50ea10d880daa23289a5 (MD5) / Made available in DSpace on 2017-03-07T14:03:33Z (GMT). No. of bitstreams: 1 Dissertacao Eluíza Thomas.pdf: 2451474 bytes, checksum: bb0c2710663f50ea10d880daa23289a5 (MD5) Previous issue date: 2017-03-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. / Brazil is one of the countries with the highest global biodiversity, but few plant species had their properties evaluated. Essential oils are volatile compounds produced by plants that contribute to their adaptation to the environment. Studies that advances knowledge on the toxic potential of medicinal plants are extremely relevant, allowing you to assess the safety of their use. Essential oils of five species of native Aloysia in Rio Grande do Sul and a cultivated were obtained by hydrodistillation in a Clevenger type apparatus and the chemical composition was determined by gas chromatography coupled to mass spectrometer. The species showing 1.8-cineole as major compound were Aloysia dusenii (16.2%), A. citrodora (32.8%) and A. lycioides collected in Guaiba (49.5%) and São Marcos (17.6 %). The species A. virgata and A. polygalifolia had higher proportions of germacrene-D (11.2% and 12%, respectively) and A. chamaedryfolia spathulenol (15.6%). The species A. lycioides collected in Rosário do Sul had β-phellandrene (23.7%) as the main compound. For A. citrodora, A. lycioides and A. dusenii also evaluated the cytotoxicity of their essential oils through the lethality test front of Artemia salina. For the same species, but the solutions 1%, 10% and pure oil (v / v) also tested the effects of volatiles on the germination and initial growth of Allium cepa (onion). In bioassay A. salina there was 100% lethality in concentrations 1000 μg/mL and 500 μg/mL for the three species evaluated. Others concentrations tested the degree of mortality was directly proportional to the oil concentration. The LC50 for A. citrodora was 55.96 μg/mL, while for A. lycioides 48.12 μg/mL and A. dusenii the LC50 was 48.98 μg/mL. Species have different chemical composition resulting in various cytotoxic responses. The values found in the LC50 for the tested oils are considered highly toxic. The volatile oils of A. citrodora, A. lycioides and A. dusenii also showed inhibitory effect on the average germination time and on the initial growth of A. cepa. There was a significant inhibitory effect of essential oils in the mitotic index and index metaphase onion. Volatile also induced the occurrence of chromosomal abnormalities, such as non-oriented chromosomes in metaphase, sticky, c-mitosis, micronuclei and buds at interphase. The essential oil of A. citrodora proved to be the most toxic among the species assessed. The present study suggests that the majority compounds and minority species of Aloysia have synergistic action resulting in the observed effects, both for the cytotoxic activity as genotoxic. This work contributed significantly to increase knowledge of the diversity and composition essential oils of species of Aloysia and also to the mode of action of the understanding of natural products with allelopathic potential and the ecological relationship between the species, and report on the toxicity of the volatile oil of these species that are widely used in folk medicine.

O objetivo do presente trabalho foi avaliar o efeito antioxidante do óleo essencial de orégano e alfavacão no perfil de ácidos graxos da gordura de palma, utilizada em processo industrial de batata frita tipo chips, em diferentes etapas do processamento, visando reduzir o estado oxidativo da mesma. O óleo essencial foi obtido do resíduo do orégano da indústria de condimentos, e analisou-se também óleo essencial de orégano comercial. A atividade antioxidante do óleo essencial de orégano foi feita pelo método de DPPH, apresentando valores de IC50 de 797,04 µg.mL-1 e de 424,25 µg.mL-1, para o resíduo de orégano e orégano comercial, respectivamente . Em relação ao conteúdo de fenóis totais, o óleo essencial de orégano comercial apresentou 0,167±0,058 g EAG.g-1. Baseado nestes resultados, foram adicionados 50, 100 e 150ug.g-1 de óleo essencial de orégano comercial nas gorduras de palma. Foi realizada a análise do perfil de ácidos graxos por cromatografia gasosa das gorduras de palma sem fritura e sem adição de óleo essencial, assim como das gorduras com diferentes concentrações de óleo essencial, sendo que todas foram submetidas a três processos de fritura, em um único dia. Na segunda etapa do projeto, comparou-se o efeito do óleo essencial de orégano comercial com o óleo essencial do alfavacão obtido experimentalmente, na concentração de 100ug.g-1 em gordura de palma, e submetida a três processos de fritura durante onze ciclos. Os resultados mostraram que o perfil lipídico da gordura de palma foi semelhante ao descrito em literatura, na qual observou-se uma diminuição na concentração de ácidos graxos poliinsaturados e, por consequência, um aumento proporcional dos ácidos graxos saturados com o número de frituras; sendo observada um aumento nos valores de ácidos graxos saturados totais, passando de 43,36% (controle) para 43,60% (gordura de palma com óleo essencial após 11ciclos de frituras). Esse fato comprova que, durante o processo de fritura, há o aumento na taxa de formação de ácidos graxos saturados. Na análise do perfil de ácidos graxos, a adição de óleo essencial de orégano na concentração de 100 ug.g-1 até 3 ciclos de frituras apresentou efeito na redução da formação dos ácidos graxos trans. Todavia, realizando-se 11 ciclos de frituras não foi observado efeito dos óleos essenciais sobre a formação de compostos trans. Este fato pode sugerir que, nas condições estudadas neste projeto, os ciclos de fritura podem não ter ocasionado a formação de ácidos graxos saturados. / The objective of this study was to determine the antioxidant effect of essential oregano and alfavaca oil on the fatty acid profile of palm oil, used in industrial potato chips processing, aiming to reduce the oxidative state of palm oil. Essential oregano oil was obtained from industrial residues and commercial essential oregano oil was also acquired. The antioxidant activity of Oregano’s essential oil was taken by DPPH method. The DPPH analysis of the essential oil of oregano residue resulted in an IC50 of 797.04 mg.mL-1 and the essential oil of commercial oregano was 424.25 mg.mL-1. Regarding the content of total phenols, the essential oil of commercial oregano showed 0.167 ± 0.058 ug EAG.g-1. Based on these results, concentrations of 50, 100 e 150ug.g-1 of commercial oregano essential oil was added to palm oil and the fatty acid profile was determined by gas cromatography. Analysis were done with palm oil without being used in frying processes and without added essential oil, as well as with the different essential oil concentrations submitted at three frying processes at one single day. In the second part of the project, the effect of oreganos’s comercial essential oil compared to alfavacão essential oil, at the concentration of 100ug.g-1 in palm oil, and submitted to three frying processes during eleven cycles, was studied. The lipid profile was similar to that described in the literature, which an increase in the number of frying times caused a polyunsaturated fatty acids decrease and, therefore, a proportional increase in saturated fatty acids. It was noted an increase in the amounts of total saturated fatty acids from 43.36% (control) to 43.60% (palm oil with essential oil after 11 frying cycles at the concentration of 100ug.g-1). This fact proves that during the frying process, there is an increase in the rate of formation of saturated fatty acids. However, the addition of oregano essential oil did not provide significant change in the fatty acids of palm oil used in frying process of potato chips. The addition of oregano essential oil in a concentration of 100 ug./mL-1 until the third frying cycle showed a reduction effect of trans fatty acid formation. Although, during 11 frying cycles it was not noticed the essential oil effect under trans fatty acid formation. It can be suggested that this factor may be correlated to the frying time, which may not have been sufficient for significant formation of saturated and trans compounds.

Orientador: Ary Fernandes Júnior / Coorientador: José Maurício Sforcin / Coorientador: Ana Angélica Henrique Fernandes / Banca: Vera Lúcia Mores Rall / Banca: Fernanda Mani / Banca: Jairo Kenupp Bastos / Banca: Wander Rogério Pavanelli / Resumo: Produtos naturais, como os óleos essenciais, possuem diversas propriedades biológicas bem como são importantes fontes para a pesquisa. Além disto, os óleos essenciais estão presentes em nossa rotina, tanto em produtos como xampus, sabonetes e alimentos, assim como em alternativas terapêuticas como a aromaterapia. Objetivamos investigar atividades biológicas de produtos naturais, sendo os resultados apresentados na forma de três manuscritos. Investigamos a ação antibacteriana dos óleos essenciais de tea tree (Melaleuca alternifolia), gerânio (Perlagonium graveolens), palmarosa (Cymbopogon martinii) e seus respectivos compostos majoritários 1-terpinen-4-ol, citronelol e geraniol em sua fase líquida e gasosa (Capítulo I). Foi demonstrada a eficácia dos óleos essenciais e seus principais componentes como agentes antimicrobianos por contato direto e na forma de vapor utilizando três diferentes metodologias e foram destacados os danos causados por esses vapores utilizando informações de microscopia eletrônica de transmissão. Em outra parte do estudo, objetivamos analisar parâmetros bioquímicos séricos e o estresse oxidativo de ratos submetidos à inalação do óleo essencial de palmarosa e geraniol durante 30 dias (Capítulo II). Ratos tratados com os produtos naturais apresentaram níveis de colesterol total diminuídos bem como foi verificado efeitos benéficos do óleo essencial sobre o estresse oxidativo. Finalizando o estudo, avaliamos a ação imunomoduladora do óleo essencial de C. martinii e geraniol quanto à produção de citocinas pró- e anti-inflamatórias por monócitos humanos (Capítulo III). As diferentes concentrações testadas não mostraram efeitos citotóxicos em monócitos. A produção do fator de necrose tumoral (TNF)-α não foi afetada por C. martinii e geraniol, sendo que somente na concentração de 5 μg/mL de C. martinii, houve estímulo para a sua produção. Por outro lado, em todas as... / Abstract: Natural products such as essential oils have diverse biological properties and are important sources for research. In addition, the essential oils are present in our daily lives, both in products like shampoos, soaps and foods, as well as alternative therapies such as aromatherapy. We aimed to investigate the biological activities of natural products, the results are presented in the form of three manuscripts. We investigated the antibacterial action of essential oils of tea tree (Melaleuca alternifolia), geranium (Perlagonium graveolens), palmarosa (Cymbopogon martinii) and their major compounds respective 1-terpinen-4-ol, citronellol and geraniol in liquid and vapor phase (Chapter I). The effectiveness of essential oils and their main components such as antimicrobial agents, was demonstrated by direct contact and vapor form using three different methodologies and the information of the damage caused by these vapors using transmission electron microscopy. In another part of the study, we aimed to assess serum biochemical parameters and oxidative stress in rats subjected to inhalation of palmarosa essential oil and geraniol during thirty days (Chapter II). Mices treated with natural products had total cholesterol levels decreased and it was found beneficial effects of the essential oil on oxidative stress. Concluding the study, we evaluated the immunomodulatory action of C. martinii essential oil and geraniol as the production of proand anti-inflammatory by human monocytes (Chapter III). Different concentrations tested showed no cytotoxic effects on monocytes. The production of tumor necrosis factor (TNF)-α was not affected by C. martinii and geraniol, and only the concentration of 5 mg/mL of C. martinii, there was a stimulus for their production. Furthermore, at all concentrations of geraniol and C. martinii increased by interleukin (IL) -10 by human monocytes. The results showed that the noncytotoxic concentrations of oil and geraniol ... / Doutor

O óleo essencial de Citrus latifolia Tanaka (limão Tahiti) possui grande valor comercial e aplicações em diversos tipos de indústrias. A extração enzimática de óleos vegetais fixos aumenta o rendimento, consome pouca energia e causa um mínimo impacto ambiental, porém poucos estudos avaliaram o seu emprego para a extração de óleos essenciais de plantas aromáticas. Em vista disso, este trabalho teve como objetivo contribuir para o desenvolvimento de uma tecnologia enzimática para a extração do óleo essencial de cascas de C. latifolia Tanaka, além de avaliar a percentagem de compostos bioativos, como cumarinas, nos resíduos dos processos de extração. Para tanto, foram realizados pré-tratamentos enzimáticos nas cascas, através de um complexo constituído principalmente por celulases, caracterizado em papel filtro (FPA), e posterior extração do óleo por hidrodestilação. Nos três primeiros experimentos foram avaliados o efeito da carga enzimática (5, 7 e 12 FPA/g de substrato), o efeito do tempo de pré-tratamento enzimático (1, 2 e 3 horas) e o efeito do pré-tratamento em cascas trituradas sobre o rendimento e a composição do óleo essencial obtido por 1 hora de hidrodestilação. Em outro experimento foi avaliada a possibilidade de redução no tempo de hidrodestilação através do pré-tratamento enzimático, utilizando-se cargas de 5, 7 e 12 FPA/g em cascas trituradas, calculando-se o rendimento em óleo durante a hidrodestilação em diferentes intervalos de tempo (10, 15, 20, 30, 40, 50 e 60 minutos). As cumarinas foram extraídas com hexano dos resíduos líquidos e sólidos das hidrodestilações através de extração líquido-líquido e soxhlet, respectivamente. As análises dos compostos dos óleos essenciais e das cumarinas foram feitas por cromatografia gasosa (GC) e cromatografia gasosa acoplada à espectrometria de massas (GC/MS). Nos três primeiros experimentos descritos não foram verificadas diferenças estatísticas entre os rendimentos em óleo das amostras pré-tratadas enzimaticamente e os controles, demonstrando que o pré-tratamento enzimático não alterou o rendimento em óleo obtido por 1 hora de hidrodestilação. Porém, a análise dos componentes dos óleos permitiu observar um aumento nas proporções de alguns compostos oxigenados (p<0,05), responsáveis pela qualidade do aroma. No experimento onde foi avaliada a diminuição do tempo de hidrodestilação, verificou-se que o pré-tratamento com carga de 5 FPA/g atingiu o rendimento máximo em torno de 30 minutos do processo de destilação, enquanto que no controle o rendimento máximo foi em torno de 50 minutos. Utilizando-se a carga de 7 FPA/g, o rendimento máximo foi atingido em torno de 20 minutos, o mesmo ocorrendo com a carga de 12 FPA/g, enquanto que no controle foi em torno de 40 e 50 minutos, respectivamente. Estes resultados indicam que o pré-tratamento enzimático reduz o tempo de hidrodestilação apresentando vantagens do ponto de vista de custo energético e de integridade dos componentes do óleo, visto a redução do tempo de exposição do material vegetal à temperatura de ebulição da água, preconizando as bases para um processo tecnológico que envolve pré-tratamento enzimático associado à hidrodestilação para ser empregado na obtenção de óleo essencial de C. latifolia Tanaka. Em relação às cumarinas, os resultados obtidos indicaram que a percentagem da maioria desses compostos não foi alterada quando as amostras sofreram pré-tratamento enzimático. Entretanto, propõe-se que os resíduos gerados pela hidrodestilação podem ser aproveitados e utilizados como fonte de cumarinas. / Citrus latifolia Tanaka (Tahiti lime) essential oil has a high commercial value and a large application in different industries. The enzymatic extraction of vegetable oils increases yields extraction, energy efficient and cause minimal environmental impact, but few studies have evaluated its use for the extraction of essential oils from aromatic plants. As a result, this study aimed to contribute to the development of enzymatic technology for extraction of essential oil from peels of C. latifolia Tanaka, and assess the proportion of bioactive compounds such as coumarins, in wastes extraction processes. To do so, it was performed enzymatic pretreatment of the peels, through a complex composed primarily of cellulases, characterized in filter paper (FPA), and subsequent extraction of oil by hydrodistillation. In the first three experiments were evaluated the effect of enzyme loading (5, 7 and 12 FPA/g substrate), the effect of time of enzymatic pretreatment (1, 2 and 3 hours) and the effect of pretreatment on crushed peels, on yield and composition of essential oil obtained by 1 hour hydrodistillation. In another test, it was evaluated the possibility of reducing the time hydrodistillation by enzymatic pretreatment, using loads of 5, 7 and 12 FPA/g of crushed peels, calculating the oil yield during the hydrodistillation at different intervals time (10, 15, 20, 30, 40, 50 and 60 minutes). The coumarins were extracted from the liquid and solid wastes from hydrodistillations with hexane through liquid-liquid extraction and soxhlet, respectively. The analysis of the compounds of essential oils and coumarins were made by gas chromatography (GC) and gas chromatography-mass spectrometry (GC / MS). In the first three experiments described not statistical differences were found between the oil yields of enzymatically pretreated samples and controls, demonstrating that the enzymatic pretreatment did not affect the oil yield obtained by 1 hour hydrodistillation. However, the analysis of the oil components allowed to observe an increase in the proportions of some oxygenated compounds (p < 0,05), responsible for the quality of aroma. In the experiment where was evaluated the short-time hydrodistillation, it was found that pretreatment with a load of 5 FPA/g reached the maximum yield of about 30 minutes from the distillation process, while in the control the maximum yield was about 50 minutes. Using the load of 7 FPA/g, the maximum yield was reached in about 20 minutes, the same happened with the load of 12 FPA/g, while in the control was around 40 and 50 minutes, respectively. These results indicate that enzymatic pretreatment reduces the time hydrodistillation with advantages in terms of cost efficiency and integrity of the oil components, since the reduction in exposure time of the plant material at a temperature of boiling water, pointing out the foundation for a technological process that involves enzyme pretreatment associated with hydrodistillation to be employed in obtaining essential oil of C. latifolia Tanaka. For the coumarins, the results indicated that the percentage of most of these compounds was not altered when the samples were enzymatically pretreated. However, it is proposed that the waste generated by hydrodistillation can be recovered and used as a source of coumarins.

O Brasil é um dos países com maior biodiversidade mundial, porém, poucas espécies vegetais tiveram suas propriedades avaliadas. Os óleos essenciais são compostos voláteis produzidos pelas plantas que contribuem para a sua adaptação ao meio ambiente. Estudos que ampliem o conhecimento sobre o potencial tóxico de plantas medicinais são extremamente relevantes, permitindo que se avalie a segurança do seu uso. Os óleos essenciais da parte aérea de cinco espécies de Aloysia nativas no Rio Grande do Sul e uma cultivada foram obtidos por hidrodestilação em aparelho do tipo Clevenger e a composição química foi determinada por cromatografia gasosa acoplada ao espectrômetro de massas. As espécies que apresentaram 1.8-cineol como composto majoritário foram Aloysia dusenii (16.2%), A. citrodora (32.8%) e A. lycioides coletada em Guaiba (49.5%) e São Marcos (17.6%). A espécie A. polygalifolia e A. virgata tiveram maiores proporções de germacreno-D (11.2% e 12%, respectivamente) e A. chamaedryfolia apresentou espatulenol (15.6%). A espécie A. lycioides coletada em Rosário do Sul teve β-felandreno (23.7%) como o composto principal. Para as espécies A. citrodora, A. lycioides e A. dusenii também se avaliou a toxicidade dos seus óleos essenciais através do teste de letalidade frente a Artemia salina. Para as mesmas espécies, mas nas soluções 1%, 10% e óleo puro (v/v) também se testou os efeitos dos óleos essenciais sobre a germinação e o desenvolvimento inicial de Allium cepa (cebola). No bioensaio de A. salina observouse 100% de letalidade nas concentrações 1000 μg/mL e 500 μg/mL para as três espécies avaliadas. Nas demais concentrações avaliadas o grau de letalidade foi diretamente proporcional à concentração dos mesmos. O LC50 para A. citrodora foi de 55.96 μg/mL, para A. lycioides 48.12 μg/mL e A. dusenii o LC50 foi de 48.98 μg/mL. As espécies possuem composição química distinta o que resulta em respostas citotóxicas diversas. Os valores encontrados no LC50 para os óleos testados são considerados extremamente tóxicos. Os óleos voláteis de A. citrodora, A. lycioides e A. dusenii também apresentaram efeito inibitório sobre o tempo médio de germinação e sobre o crescimento inicial de A. cepa. Ainda, observou-se efeito inibitório significativo desses óleos essenciais sobre a atividade mitótica e metafásica na cebola. Os voláteis também induziram a ocorrência de anormalidades cromossômicas, como cromossomos não-orientados na metáfase, aderências, c-mitoses, micronúcleos e brotos nucleares. O óleo essencial de A. citrodora demonstrou ser o mais tóxico entre as espécies avaliadas. O presente estudo sugere que os compostos majoritários e minoritários das espécies de Aloysia têm ação sinérgica resultando nos efeitos observados, tanto para a atividade citotóxica como genotóxica. Esse trabalho contribuiu significativamente para ampliar os conhecimentos sobre a diversidade e composição química dos voláteis das espécies de Aloysia do RS e também para o entendimento do modo de ação dos produtos naturais com potencial alelopático e a relação ecológica entre as espécies, além de reportar sobre a toxicidade do óleo essencial dessas espécies que são muito utilizadas pela medicina popular. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. / Brazil is one of the countries with the highest global biodiversity, but few plant species had their properties evaluated. Essential oils are volatile compounds produced by plants that contribute to their adaptation to the environment. Studies that advances knowledge on the toxic potential of medicinal plants are extremely relevant, allowing you to assess the safety of their use. Essential oils of five species of native Aloysia in Rio Grande do Sul and a cultivated were obtained by hydrodistillation in a Clevenger type apparatus and the chemical composition was determined by gas chromatography coupled to mass spectrometer. The species showing 1.8-cineole as major compound were Aloysia dusenii (16.2%), A. citrodora (32.8%) and A. lycioides collected in Guaiba (49.5%) and São Marcos (17.6 %). The species A. virgata and A. polygalifolia had higher proportions of germacrene-D (11.2% and 12%, respectively) and A. chamaedryfolia spathulenol (15.6%). The species A. lycioides collected in Rosário do Sul had β-phellandrene (23.7%) as the main compound. For A. citrodora, A. lycioides and A. dusenii also evaluated the cytotoxicity of their essential oils through the lethality test front of Artemia salina. For the same species, but the solutions 1%, 10% and pure oil (v / v) also tested the effects of volatiles on the germination and initial growth of Allium cepa (onion). In bioassay A. salina there was 100% lethality in concentrations 1000 μg/mL and 500 μg/mL for the three species evaluated. Others concentrations tested the degree of mortality was directly proportional to the oil concentration. The LC50 for A. citrodora was 55.96 μg/mL, while for A. lycioides 48.12 μg/mL and A. dusenii the LC50 was 48.98 μg/mL. Species have different chemical composition resulting in various cytotoxic responses. The values found in the LC50 for the tested oils are considered highly toxic. The volatile oils of A. citrodora, A. lycioides and A. dusenii also showed inhibitory effect on the average germination time and on the initial growth of A. cepa. There was a significant inhibitory effect of essential oils in the mitotic index and index metaphase onion. Volatile also induced the occurrence of chromosomal abnormalities, such as non-oriented chromosomes in metaphase, sticky, c-mitosis, micronuclei and buds at interphase. The essential oil of A. citrodora proved to be the most toxic among the species assessed. The present study suggests that the majority compounds and minority species of Aloysia have synergistic action resulting in the observed effects, both for the cytotoxic activity as genotoxic. This work contributed significantly to increase knowledge of the diversity and composition essential oils of species of Aloysia and also to the mode of action of the understanding of natural products with allelopathic potential and the ecological relationship between the species, and report on the toxicity of the volatile oil of these species that are widely used in folk medicine.

Syzygium cordatum Hoscht ex. C Krauss, also known as water berry, is normally used by the people of South Africa for respiratory ailments including tuberculosis, stomach complaints, treatment of wounds and as emetics. An extract of the leaves can be used as a purgative for diarrhoea treatment. The leaves of Syzygium cordatum Myrtaceae were obtained from the Eastern Cape Province of South Africa, air dried and sequential solvent extraction was done to obtain various non volatile crude extracts. The volatile extract, that is the essential oil was extracted from the leaves using hydrodistillation and analysis of compounds was done by GC/MS for composition. 32 compounds were obtained from the fresh leaves and 18 compounds were obtained from the dry leaves. The fresh oil contains caryophyllene (11.8 percent) and caryophyllene oxide (11.1 percent) as the main sesquiterpene component. α-Pinene(5.0 percent) was the only monoterpene compound identified in the fresh oil in substantial amount. The dry leaves oil had copanene (17.0 percent), β-Caryophellene (26.0 percent), cubenol (6.5 percent) and caryophellene oxide (14.2 percent) as the dominant constituent of the oil. Summary of the classes of compounds in the oil revealed that the chemical profile of both oils were dominated by sesquiterpenoid compounds. This is the first time that terpenoids compounds are being identified in both the fresh and dry leaf oil of S. cordatum. Hexane leaf extract was selected due to the interest in the terpenoid compounds. Column chromatography of the hexane crude gave five (5) of which two are fully reported. The isolates were fully elucidated using spectroscopic methods to be β-Sitosterol (HC3) and Friedela-3-one (HC1A/HC1D). Cytotoxicity analysis was carried out on the crude using the Brine shrimps assay. Isolates 1C and1D showed significant lethality using the brine shrimps assay with lethality values (LC50) of 4.105mg/ml for HC1C and 4.11mg/ml for 1D/1A respectively.

SFME and HD for the extraction of essential oil in Lavandula officinalis in Alice have been reported. A total of 59 compounds were identified with the major compound being 1,8-cineole, an oxygenated monoterpene, with 46.89% and 44.84% yield obtained for HD and SFME respectively. Charge transfer (CT) complexes formed between α-pinene, 1,8-cineole and camphor as electron donors with iodine as the electron acceptor have been studied spectrophotometrically in methylene chloride solution. The Benesi- Hildebrand equation has been applied to estimate the formation constant (Kf) and molecular extinction coefficient (εCT). The value of Kf is the highest in camphor-I2 complex compared to the other two complexes. Antibacterial assessment was carried out on the various reagents, determining the MIC of individual reagents and in combination. The results show an improvement, on combination of the various reagents than when tested alone.

The common maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), a well known pest of stored-maize grain in most parts of the world, was identified as one of the major constraints of harvested maize grains in the Eastern Cape Province, South Africa. The use of plants or their products is one of the recent methods being investigated for insect pest control worldwide. Therefore, the main aim of the present study was to identify available plants in the Eastern Cape that could be used to combat the problem of Sitophilus zeamais in stored-maize grains. For the realization of the aims of this research, the following studies were carried out; a preliminary survey was conducted to obtain baseline information on the farmers’ knowledge and experience of indigenous insect pest control methods in the Eastern Cape. Also, studies on the insecticidal potential of the essential oils of some plants were investigated against the maize weevil. The quality parameters of maize grains treated with the essential oils was also studied and, using a rat model, the toxicity of the essential oils was investigated. The outcome from this study revealed that there is awareness amongst the farmers in the Eastern Cape on the use of plants or their products to control insect pests. Unfortunately, such methods are currently being neglected and the knowledge of their application was found to be eroding. Among the various essential oils screened were those from Mentha longifolia L. and Tagetes minuta L. which evoked an appreciable level of contact, fumigant and repellent toxicity on the maize weevil. Further work done to determine the effects of the oils on maize stored over a period of three months revealed that the two oils had no adverse effect on the proximate compositions and some quality parameters of the stored maize. However, the toxicological study conducted on rats showed that the oils at tested concentrations exhibited some level of toxicity. It is, therefore, suggested that the essential oils of M. longifolia and T. minuta should not be used to treat maize grains intended for human consumption.

Variations in the yield, chemical composition, antibacterial, and antioxidant properties of the essential oils of Rosmarinus officinalis L. cultivated in Alice, Eastern Cape of South Africa over a period of 12 months using the solvent-free microwave extraction and traditional hydrodistillation methods were evaluated. The GC-MS analyses of the essential oils revealed the presence of 33 compounds with 1,8-cineole, a-pinene, camphor, verbenone, bornyl acetate and camphene constituting about 80 percent of the oils throughout the period of investigation, with the solvent-free microwave extraction method generally yielding more of the major components than the hydrodistillation method. Each of the major components of the oils varied in quantity and quality of yield at different periods of the year. The method of extraction and time of harvest are of importance to the quantity and quality of essential oil of Rosmarinus officinalis. Higher amounts of oxygenated monoterpenes such as borneol, camphor, terpene- 4-ol, linalool, a-terpeneol were present in the oil of SFME in comparison with HD. However, HD oil contained more monoterpene hydrocarbons such as a-pinene, camphene, β-pinene, myrcene, a-phellanderene, 1,8-cineole, trans- β-ocimene, γ-teprinene, and cis-sabinene hydrate than SFME extracted oil. Accumulation of monoterpene alcohols and ketones was observed during maturation process of Rosmarinus leaves. Quantitative evaluation of antibacterial activity, minimum inhibitory concentration values were determined using a serial microplate dilution method. The essential oils obtained using both methods of extraction were active against all the bacteria tested at a concentration of 10 mg mL-1. The minimum inhibitory concentrations for the SFME extracted oils ranged between 0.23 and 1.88 mg mL-1, while those of the HD extracted oils varied between 0.94 and 7.5 mg mL-1, thus suggesting that the oil obtained by solvent free microwave extraction was more active against bacteria than the oil obtained through hydrodistillation. The antioxidant and free radical scavenging activity of the obtained oils were tested by means of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH+) assay and β- carotene bleaching test. In the DPPH+ assay, while the free radical scavenging activity of the oil obtained by SFME method showed percentage inhibitions of between 48.8 percent and 67 percent, the HD derived oil showed inhibitions of between 52.2 percent and 65.30 percent at concentrations of 0.33, 0.50 and 1.0 mg mL-1, respectively. In the β-carotene bleaching assay, the percentage inhibition increased with increasing concentration of both oils with a higher antioxidant activity of the oil obtained through the SFME than the HD method. Thin layer chromatography (TLC) was used to analyze the chemical composition of the extracts using three eluent solvent systems of varying polarities i. e. CEF, BEA and EMW and sprayed with vanillin-sulfuric acid. The chemical composition of the different extracts was similar with the exception of methanol and water extracts which had only one or two visible compounds after treating with vanillin-spray reagent. To evaluate the number of antibacterial compounds present in the fractions, bioautography was used against two most important nosocomial microorganisms. S. aureus (Gram positive) and E. coli (Gram negative). Nearly all the crude serial extraction fractions contained compounds that inhibited the growth of E. coli. The hexane extract had the most lines of inhibition followed by ethyl acetate. Bioassay-guided fractionation against E. coli was used to isolate antibacterial compounds. The largest number of antibacterial compounds occurred in the hexane fraction. Furthermore we tried to complete the characterization by extracting and studying other biologically important plant metabolites such as phenolic compounds to evaluate the antioxidant capacity of Rosmarinus extracts.

The roots and rhizomes of Anemopsis Californica (Nutt.) Hook and Arn. (family Saururaceae) have been used by the early Spanish Americans and Indians to treat a variety of ailments. The plant is commonly known as Yerba del Mansa, Yerba Mansa, or Manza. We decided to investigate the essential oil of Anemopsis Californica in greater detail. The results of our investigation to date are included and described in this thesis.