O chá é uma das bebidas mais consumidas no mundo. Os chás provenientes da planta Camellia sinensis possuem altos teores de antioxidantes, o que significa que podem ter diversos efeitos benéficos na preservação da saúde. Durante séculos, a humanidade procura formas de conservar melhor e por mais tempo os alimentos que consomem. O processo de irradiação de alimentos é uma técnica amplamente utilizada em todo o mundo e é indicada por diversos órgãos de saúde e sanitários de diversos países. A radiação interage com o material causando dois tipos de efeitos, o efeito direto e o efeito indireto. No efeito direto a radiação interage com a molécula de DNA, causando a quebra dessa molécula, inativando a célula. No efeito indireto, que representa 70% da interação, a radiação quebra a molécula de água presente no meio, em um processo chamado de radiólise, criando uma série de radicais livres que vão interagir com os componentes celulares, levando a morte da célula. Portanto, o objetivo deste trabalho foi estudar os efeitos da radiação gama em dois tipos de chás da planta Camellia sinensis irradiados com diferentes valores de atividade de água. As amostras de chá verde e chá preto tiveram suas Aw ajustadas a três valores (Aw alta, Aw média e Aw baixa). As amostras foram irradiadas em fonte de 60Co nas doses de 0; 1,0; 1,5; 2,0; 2,5; 5,0; 7,5 e 10,0 kGy. As análises utilizadas foram: microbiologia por semeadura de superfície, quantificação de fenólicos totais, análise da atividade antioxidante por ORAC e identificação e quantificação dos principais antioxidantes presente nessas bebidas. Foi possível constatar que quanto maior a quantidade de água livre presente no meio, menor foi a dose para realizar o controle microbiológico. O chá verde mostrou ser um pouco mais suscetível a irradiação com alta Aw do que o chá preto, pois houve variação da quantidade de fenólicos e flavonóides, diminuindo a quantidade desses compostos em algumas doses, mas também houve aumento da quantidade em outras doses. Entretanto em ambos os chás, essas mudanças podem ser consideradas insignificantes, uma vez que não houve diferença da atividade antioxidante em doses de até 10 kGy. A dose de 5,0 kGy foi a dose mínima que garantiu o controle microbiológico e não causou alterações nos parâmetros analisados. / Tea is the most consumed beverage in the world. Teas from Camellia sinensis plant have high levels of antioxidants, which mean that they may have several beneficial effects on health preservation. For centuries, mankind looks for ways to conserve better and for a longer time the food that they eat. The food irradiation process is a largely technique used worldwide, and is recommended by many health agencies and authorities of several countries. The radiation interacts with the material causing two kinds of effects, the direct and the indirect effect. In the direct effect the radiation interacts with the DNA molecule, breaking it, and then inactivates the cell. In the indirect effect, which represents 70% of the interaction, the radiation breaks the water molecule in a process denominated radiolysis, creating a number of free radicals that will interact with the cellular components, leading to the cell death. Therefore, the aim of this work is to study the effects of gamma radiation on two kinds of tea from Camellia sinensis plant irradiated with different water activities. The green tea and black tea samples had their Aw adjusted to three values (high Aw, medium Aw, and low Aw). The samples were irradiated in 60Co source at doses of 0, 1.0, 1.5, 2.0, 2.5, 5.0, 7.5, and 10.0 kGy. The analyses used were: microbiology by plate count, total phenolic compounds quantification, antioxidant activity by ORAC assay, and identification and quantification of main antioxidants in these beverages. It was noted that the greater the quantity of free water present in the medium, the lower was the dose to achieve microbiological control. The green tea showed to be a little more susceptible to irradiation by high Aw once there was more variation in the amount of flavonoids and phenolics than the black tea, decreasing the amount of these compounds in some doses, but increasing the amount in other ones. However in both teas, these changes can be considered insignificant, since there was no difference in antioxidant activity at doses up to 10 kGy. The dose of 5.0 kGy was the minimum dose that secured the microbiological control and had no changes on the parameters analyzed.

Introdução. Os efeitos antimicrobianos dos óleos essenciais têm sido relatados na literatura científica, sobretudo referentes ao óleo essencial de Tea Tree (Melaleuca alternifolia). Tal óleo essencial tem demonstrado propriedades antissépticas e pode representar uma alternativa de um produto natural para higienização das mãos nos estabelecimentos de assistência à saúde que por ora utilizam predominantemente produtos à base de triclosan e clorexidina. Objetivo. Avaliar a eficácia da higiene das mãos na redução da carga microbiana realizada com duas formulações de sabonetes líquidos já disponíveis no mercado, contendo: óleo essencial de Tea Tree 0,3% e sabonete com triclosan na concentração de 0,5%; comparar dois procedimentos referência, sendo um da metodologia oficial (soft soap) e o outro da versão draft (soft soap + propan-2-ol). Método. Foram utilizadas as diretrizes da metodologia do Comitê Europeu de Padronização, EN 1499, indicada para avaliar a eficácia antimicrobiana de produtos para higiene das mãos. A metodologia recomenda a contaminação artificial das mãos de 12 a 15 voluntários sadios com Escherichia coli K12, seguida pela higienização das mãos com cada produto em avaliação. Ainda segundo a metodologia, os resultados além de serem comparados entre si, são comparados com um sabão de referência (soft soap), no mesmo voluntário, dia e sob condições ambientais semelhantes. Foi realizada a contagem do número de microrganismos antes (pré-valores) e após (pós-valores) cada procedimento. O fator de redução logaritimica entre os pré e pós-valores representou a atividade antimicrobiana de cada produto testado, permitindo evidenciar a eficácia dos produtos em teste comparativamente ao produto referência (soft soap seguido ou não por propan-2-ol). Resultados. Em termos de redução logarítmica, o sabonete contendo óleo essencial de Tea Tree à 0,3% foi mais eficaz do que o sabonete contendo triclosan à 0,5% (3,89 log10 x 3,59 log10), porém, pelo teste de Wilcoxon, não houve diferença estatisticamente signficante. Em relação à eficácia antimicrobiana, nenhum dos dois sabonetes apresentou desempenho superior a nenhum dos dois procedimentos referência (soft soap ou soft soap + propan-2-ol). O procedimento de higienização das mãos de referência utilizando soft soap + propan-2-ol (proposto pela versão draft da metodologia EN 1499), demonstrou-se mais eficaz do que apenas o uso do soft soap (descrito na metodologia oficial). / Introduction. The antimicrobial effects of essential oils have been reported in scientific literature, especially about essential oil of Tea Tree (Melaleuca alternifolia). This essential oil has shown antiseptic properties and may represent a natural and alternative product for hand hygiene in health care establishments that currently use products based on triclosan and chlorhexidine. Objective. Evaluate the efficacy of hand hygiene in reducing microbial load performed with two differents formulations of liquid soaps available: Tea Tree essential oil 0.3% soap and triclosan 0.5% soap; compare two references procedure, one of the official methodology (soft soap) and one of the draft version (soft soap + propan-2-ol). Method. Was used the guidelines of the European Committee for Standardization, EN1499 methodology, indicated to evaluate the efficacy of antiseptics for hand hygiene. The methodology recommends the artificial contamination of hands from 12 to 15 healthy volunteers with Escherichia coli K12 followed by washing hands with each product under evaluation. According to the methodology, results should be compared between products and with a reference soap (\"soft soap\"), in the same subject, same day and under similar environmental conditions. Were counted the number of microorganisms before (pre-values) and after (post-values) handwashing. The logarithmic reduction factor between pre-and post-values represents the antimicrobial activity of each product under test, showing the efficacy of products under test compared to the reference product (soft soap follwed or not followed by propan-2-ol). Results. In terms of logarithmic reduction, the soap containing the tea tree essential oil 0.3% was more efficacious than the soap containing 0.5% triclosan (3,89 log10 x 3,59 log10). However, the Wilcoxon test does not detected statistically significant diference. Regarding the antimicrobial efficacy, none of the two soaps showed superior performance to either references procedure (soft soap or soft soap + propan-2-ol). The procedure for reference hand hygiene using soft soap + propan-2-ol, (proposed by the draft version of the methodology EN 1499) showed to be more efficacious than use only soft soap (described in the oficial methodology).

Este estudo originou-se do interesse em investigar a sensibilidade do IRDI-Questionário, adaptação do instrumento IRDI, para detecção de sinais iniciais de TEA (Transtorno de espectro de autismo). O autismo ou TEA caracteriza-se por severos déficits na interação social recíproca, na comunicação e na atividade imaginativa, assim como por padrões repetitivos e limitados de interesses e de comportamentos. Nesse sentido, deve-se ressaltar a indefinição de sua etiologia, pois, se trata de um distúrbio complexo e heterogêneo com graus variados de severidade, resultado provável de uma combinação de fatores ambientais e genéticos. Soma-se à ausência de um marcador biológico a acentuada heterogeneidade das manifestações clínicas do transtorno, daí o conceito de espectro que lhe foi atribuído. Tais condições terão como consequências dificuldades no próprio processo diagnóstico. Isso significa que o diagnóstico do autismo e as condições associadas ainda estão baseados em observações de confluência de anormalidades comportamentais nos campos social, de comunicação, do jogo e da imaginação. É importante pensar que a heterogeneidade do quadro implica que os sintomas podem não se expressar do mesmo modo em todas as crianças, apesar de apresentarem certa regularidade que permite a construção de um diagnóstico. Além disso, algumas crianças vão apresentar sinais de risco desde os primeiros meses de vida e, outras, apresentarão sintomas mais tardios. Nesse contexto, os instrumentos de avaliação são importantes ferramentas de auxílio na avaliação clínica da criança com TEA, sendo que vários pesquisadores ressaltam a importância de se realizarem triagens de crianças de até três anos de idade a fim de propiciar o diagnóstico e a intervenção ainda nos primeiros meses de vida. Com o intuito de instrumentalizar a detecção de sinais iniciais de TEA, diversos pesquisadores têm formulado protocolos com foco em diferentes formas de expressão de tais sinais e os instrumentos especializados para fins de rastreamento/ triagem têm se mostrado eficientes na detecção de sinais iniciais de TEA, além disso, são de fácil e rápida aplicação. Esta pesquisa, portanto, se propôs a investigar a sensibilidade de um instrumento para sinais iniciais de TEA, sendo que, para a investigação, participaram 72 pais de crianças/crianças divididos em 2 (dois) grupos: grupo pesquisa-TEA (32 pais) e grupo controle-típico (40 pais). Para ambos os grupos, foram utilizados o IRDI-Questionário e a CARS-BR, os quais tiverem seus resultados comparados. Utilizou-se o teste de inteligência não verbal SON-R 2½-7 no grupo pesquisa-TEA para controlar a variável DI (deficiência intelectual). Os dados foram submetidos a tratamento estatístico e as análises estatísticas demonstraram que as médias descritas pelo IRDI-Questionário foram diferentes, sendo que os IRDI do grupo TEA (85,09) são, em média, menores que os IRDI do grupo típico (129,32). Os grupos juntos mostraram alta correlação negativa entre os valores do IRDI-Questionário e da CARS-BR. Para o estudo de sensibilidade foi realizada uma análise através da curva ROC, que definiu um ponto de corte do escore gerado pelo instrumento IRDI-Questionário. A sensibilidade do IRDI-Questionário para sinais iniciais de TEA foi de 96,9%, resultado este que também indicou que o instrumento pode ser interessante para um instrumento para o rastreamento da condição estudada. Além do estudo de sensibilidade, apresentou-se, ainda, um breve estudo sobre o conceito de Intersubjetividade e suas rupturas, assim como algumas pesquisas atuais a ele referentes, relacionando-o aos indicadores IRDI e ao TEA. O conceito de intersubjetividade tem sido investigado por vários campos de conhecimento. A Psicologia do desenvolvimento é um desses campos, sendo que diversos autores nos apresentam diferentes interpretações sobre o conceito. Neste trabalho, destacou-se a importância de apresentar o conceito, pois, este guarda uma estreita relação com o autismo / This study originated from the interest in investigating the sensitivity of the IRDI - Questionnaire, adaptation of the IRDI instrument to detect early signs of ASD (autism spectrum disorder). Autism or ASD is characterized by severe deficits in reciprocal social interaction, communication and imaginative activity, as well as repetitive and restricted patterns of interest and behavior. His early appearance, profile and chronicity of symptoms are strong arguments for a biological causality, however, not defined a biological indicator present in all cases. In this sense, it should be noted the vagueness of its etiology, because it is a complex and heterogeneous disorder with varying degrees of severity, likely the result of a combination of environmental and genetic factors. Added to the absence of a biomarker a marked heterogeneity of clinical manifestations of the disorder, hence the concept of spectrum allocated to it. Such conditions will have as consequences difficulties in itself diagnostic process. This means that the diagnosis of autism and associated conditions are still based on observations of confluence of behavioral abnormalities in the social, communication, play and imagination. It is important to think that the heterogeneity of the picture implies that the symptoms can not express themselves in the same way in all children, despite having certain regularity that allows the construction of a diagnosis. In addition, some children will show signs of risk in the first months of life, and others, will present the later symptoms. In this context, the assessment tools are important aid tools in the clinical evaluation of children with ASD, and several researchers emphasize the importance of conducting trials of children under three years of age in order to provide diagnosis and intervention still in first months of life. In order to manipulate the detection of initial signs of TEA, many researchers have made agreements with focus on different ways of expressing such signals and specialized tools for tracking / sorting have been shown to be effective in detecting early signs of TEA, moreover, they are quick and easy application. This research therefore aims to investigate the sensitivity of an instrument for early signs of ASD, and for research, participated 72 parents of children / children divided into two (2) groups: research - TEA group ( 32 parents ) and control group - typical (40 parents). For both groups, we used the IRDI - Questionnaire and the CARS-BR, which have their results compared. We used the non-verbal intelligence test SON- R 2½ -7 in the search -TEA group to control the variable DI (intellectual disability). The data were subjected to statistical analysis and statistical analyzes showed that the average described by IRDI - Questionnaire were different, and the IRDI TEA group (85.09) are on average smaller than the typical group IRDI (129, 32). Groups together showed high negative correlation between the values of the IRDI - Questionnaire and the CARS- BR. For the sensitivity study was carried out through an analysis of the ROC curve, it defined a cutoff score generated by IRDI - Questionnaire tool. The sensitivity of the IRDI - Questionnaire for early signs of ASD was 96.9 %, a result which also indicated that the instrument may be interesting to a tool for tracking the condition studied. In addition to the sensitivity analysis presented is also a brief study on the concept of Intersubjectivity and their breaks, as well as some current research relating thereto, relating it to IRDI indicators and TEA. The concept of intersubjectivity has been investigated by several fields of knowledge. Developmental Psychology is one of those fields, and several authors present us with different interpretations of the concept. In this work, we stressed the importance of presenting the concept, because this is closely related to autism

The aim of the present thesis is to determine whether the Tea Party candidatesʼ attitudes towards selected controversial issues influenced their electoral success and the success of the Tea Party movement as a whole. The thesis consists of two parts, theoretical and empirical. In the theoretical part the author focuses on the historical perspective of the political and party system in the United States of America, bipartism and position of third parties in the system. It also includes a brief analysis of the Democratic and Republican parties. Next, the author examines the Tea Party phenomenon - its genesis, structure, purposes and ideals. The subsequent section deals with three controversial issues, i.e. abortion, LGBT rights, and race, which reflect an ideological cleavage among the american public. The empirical part presents a case study entitled The influence of controversial issues on the (non)success of the Tea Party candidates, which deals with attitudes of the House and Senate Tea Party candidates who won the 2010 congressional elections towards the above- mentioned controversial issues.

No description available.

This thesis deals with the total antioxidant activity (TAA) evaluation of various sorts of tea (green, black, half-fermented, white, mate, rooibos and herbal) depending on the process and time of their treatment. The main emphasis is put on testing a new method of measuring the total antioxidant activity by flow coulometry. The results acquired by this method are compared to the results of the chemiluminescent Trolox equivalent antioxidant capacity (TEAC) method which is a standard for measuring the total antioxidant capacity in various materials and raw materials. The work discusses the reasons for the differences in the values found by both methods.

This thesis researches the world coffee and tea trade, especially their flows and trends in consumption and production and trade regulations that affect these flows. This paper is divided into three chapters. The first chapter focuses on the world coffee and tea production, the economic benefits of these commodities for producing countries and the outlook for these markets. Another chapter deals with the coffee and tea market, the development of demand, supply and price is examined. This chapter is also dedicated to the concept of Fair Trade and to the forms of trading on examined markets. It is explained how the commodity exchange, tea auctions and trading on the basis of financial derivatives work. The last chapter investigates the forms of international regulations that have been requested by the global coffee and tea trade.

[Truncated abstract] Conventional historical research on the tea trade focussed on the trade between the United Kingdom and China up to 1937. Very little has been done on the tea trade between China and other regions such as colonial Singapore. In addition, the focus on the overseas Chinese community in Singapore has concentrated on two opposite ends of the social ladder the rich traders or merchants who came to dominate the political, economic and social life of the community, and the coolies or those in the working class and how the harsh reality of life in colonial Singapore often quashed any dreams they had of a better life. The key focus of this dissertation is a study of the trading links between a group of Chinese traders in Singapore and commodity producers in China. To date, research into Chinese traders in Singapore has focussed on their trade in products from British Malaya such as rubber and tin. This dissertation aims to steer away from this approach, and study the relationship between Fujian tea production and trade and the Chinese tea traders in Singapore . . . This dissertation, therefore, takes a two-pronged approach. First, it examines the conditions in Fujian tea production and trade since they were the key trading concerns of the Chinese tea traders in Singapore. Secondly, the dissertation examines the political beliefs and sense of patriotism among the Chinese tea traders in Singapore and their response to major events in their lives such as the Sino-Japanese War (1937-1945), the Japanese Occupation of Singapore (1942-1945), the Chinese Civil War (1945-1949) and self-government for Singapore from June 1959.

Thesis (MScAgric)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Grey mould, caused by Botrytis cinerea, is the most important foliar disease of rooibos seedlings. Although the disease is primarily controlled with applications of fungicides, the improvement of cultural methods of disease management should lessen this dependence on chemical control. Such improvements would, however, not be possible without knowledge of the inoculum sources and dispersal of the pathogen. The aim of this study was to investigate the inoculum ecology of B. cinerea in rooibos nurseries in order to identify primary sources of inoculum and to improve the environmentally friendly management of the disease. The study was conducted in four nurseries over two production seasons (March to July 2003 and 2004). Levels of airborne inoculum of B. cinerea were monitored on a monthly basis inside and around the nurseries with spore traps. Samples of plant material and organic debris were taken in the corresponding areas to determine the incidence of plant material infected by the pathogen and the incidences of grey mould in the nurseries were recorded. Low numbers of B. cinerea colonies were observed on the spore traps. Similar levels of airborne inoculum were observed inside and around the nurseries. The incidence of plant material yielding B. cinerea was higher outside the nurseries than inside, indicating the importance of such materials as potential sources of inoculum. Since patterns of airborne inoculum observed in this study confirmed reports of the local dispersal of B. cinerea, the removal of possible hosts outside the nurseries could aid in the management of grey mould in rooibos nurseries. Resistance to dicarboximide fungicides is a genetically stable trait in B. cinerea, and therefore has the potential to be used as a phenotypic marker. This marker can be used to gain knowledge on the dispersal of B. cinerea inoculum inside and outside rooibos nurseries. Isolates of B. cinerea collected from the air and from plant material in and around four rooibos nurseries were assessed for resistance to iprodione at 1 and 3 μg/ml a.i. Some of the isolates showed resistance to iprodione at 1 μg/ml a.i. However, none of the isolates showed resistance at 3 μg/ml a.i. iprodione. The initial incidence of dicarboximide-resistance at the nurseries was slightly higher than expected. As the season progressed, the incidence of iprodione-resistant isolates decreased towards May, after which an increase was observed towards July. A relatively high percentage of isolates collected outside the nurseries was found to be dicarboximide-resistant. Two of the nurseries had a significant higher incidence of resistant isolates on plant material collected inside, than on plant material collected outside the nursery. However, when looking at resistance levels of airborne isolates, no significant differences were found in the incidence of resistant isolates sampled inside and outside the four nurseries. The data indicated the importance of organic debris and seed-borne infections in the survival and dispersal of dicarboximide-resistant isolates of the pathogen. With the current emphasis on organic agriculture the knowledge gained in this study presents valuable possibilities of improving the cultural management of grey mould in rooibos nurseries. / AFRIKAANSE OPSOMMING: Vaalvrot, veroorsaak deur Botrytis cinerea, is die belangrikste bo-grondse siekte van rooibossaailinge. Alhoewel die beheer van die siekte hoofsaaklik op die gebruik van fungisiede berus, behoort die verbetering van verbouingspraktyke hierdie afhanklikheid van chemiese beheer te verminder. Sulke verbeteringe sal egter slegs moontlik wees indien voldoende kennis van die inokulumbronne en verspreiding van die patogeen beskikbaar is. Die doel van hierdie ondersoek was om die inokulum ekologie van B. cinerea in rooibos kwekerye te ondersoek sodat primêre inokulumbronne opgespoor en omgewingsvriendelike siektebestuurspraktyke verbeter kan word. Die ondersoek is in vier kwekerye oor twee produksie seisoene (Maart tot Julie 2003 en 2004) uitgevoer. Vlakke van luggedraagde inokulum van B. cinerea is op ’n maandelikse basis met behulp van spoorvangers binne en buite die kwekerye gemonitor. Monsters van plantmateriaal en organiese materiaal is in ooreenstemmende areas geneem om die voorkoms van B. cinerea geïnfekteerde plantmateriaal vas te stel en die voorkoms van vaalvrot in die kwekerye is aangeteken. Min B. cinerea kolonies is op die spoorvangers waargeneem. Soortgelyke vlakke van luggedraagde inokulum is binne en buite die kwekerye waargeneem. Die hoër voorkoms van B. cinerea geïnfekteerde plantmateriaal buite die kwekerye as binne, dui op die belang van sulke materiaal as potensiële inokulumbronne. Aangesien die patrone van luggedraagde inokulum, soos waargeneem in hierdie ondersoek, ander berigte van B. cinerea se beperkte verspreidingsvermoë bevestig, kan die verwydering van moontlike alternatiewe gashere buite die kwekerye die bestuur van die siekte binne die kwekerye verbeter. Weerstand teen dikarboksimied fungisiede is ’n geneties-stabiele kenmerk in B. cinerea en het daarom potensiaal om as ’n fenotipiese merker gebruik te word. Hierdie merker kan gebruik word om kennis aangaande die verspreiding van B. cinerea in en om rooibos kwekerye in te samel. Botrytis cinerea isolate in lug en op plantmateriaal in en om vier rooibos kwekerye is gedurende 2003 en 2004 versamel. Die isolate is vir weerstandbiedendheid teen iprodioon by konsentrasies van 1 en 3 μg/ml aktiewe bestandeel (a.b.) getoets. Isolate met weerstand teen 1 μg/ml a.b. iprodioon is waargeneem, maar nie teen 3 μg/ml nie. Die aanvanklike voorkoms van dikarboksimiedweerstand by die kwekerye was hoër as verwag. Hierdie vlak het egter gedaal met die verloop van die seisoen tot in Mei, waarna ’n toename tot in Julie waargeneem is. Die persentasie dikarboksimied-weerstandbiedende isolate buite die kwekerye was relatief hoog. In twee van die kwekerye was die voorkoms van weerstandbiedende isolate op plantmateriaal in die kwekerye betekenisvol hoër as op plantmateriaal buite die kwekerye. Daar was egter geen betekenisvolle verskille in die voorkoms van luggedraagde weerstandbiedende isolate nie, ongeag van die kwekery of posisie. Die data dui op die belang van organiese materiaal en saadgedraagde infeksies in die oorlewing en verspreiding van dikarboksimied-weerstandbiedende isolate van die patogeen. Met die huidige klem op organiese landbou bied die inligting wat in hierdie ondersoek versamel is moontlike praktyke wat geïmplementeer kan word om die beheer van vaalvrot in kwekerye met behulp van verbouingspraktyke te verbeter.

Thesis (PhD(FoodSc))--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Potential beneficial and/or adverse modulatory effects of polyphenol-enriched extracts of rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) on the antioxidant homeostasis in the liver were investigated. Phase II metabolism of aspalathin and mangiferin, the major polyphenols of rooibos and honeybush respectively, was assessed for potential glucuronidation and sulphation. Glucuronidation resulted in a loss of antioxidant activity for aspalathin and mangiferin in post-column HPLC-DAD-DPPH• and HPLC-DAD-ABTS•+ assays and also a decreased activity of iron chelating properties of mangiferin in the FRAP assay. Two independent studies for 28 and 90 days with polyphenol-enriched extracts (PEEs) of unfermented rooibos [Aspalathus linearis (PER)] and honeybush [Cyclopia. subternata (PECsub) and C. genistoides (PECgen)] in male Fischer rats were conducted to assess possible beneficial and/or adverse biological effects. PECgen was only included in the 28 day study. PEEs were characterised by in vitro antioxidant assays and HPLC analysis. The importance of detailed chemical characterization of rooibos and honeybush when investigating biological effects in vivo is clear as distinctive biological effects and major differences in compositions were evident. Biological parameters included were serum chemical parameters, activities of selected antioxidant enzymes, levels of glutathione and the modulation of expression of oxidative stress and antioxidant defense related genes in the liver. Sub-chronic (90 days) exposure of rats to PER and PECsub both adversely affected iron absorption significantly (P<0.05) and significantly (P<0.05) and markedly lowered levels of reduced glutathione (GSH) in the liver. The high levels of polyphenol intake were implicated and interaction with glutathione was postulated to occur via catechol o-quinone conjugations with GSH. This was also implicated in the significantly (P<0.05) increased activity of glutathione reductase (GR) following 28 days. These findings suggest that PEEs from rooibos and honeybush have the potential to alter the glutathione homeostasis, which could contribute to oxidative status in the liver. PECsub resulted in alterations in the liver biliary system which was manifested as significantly (P<0.05) increased serum total bilirubin (Tbili) and alkaline phosphatase (ALP), depending on the age of the rats, level of total polyphenols and duration of exposure. The expression of a number of oxidative stress and antioxidant defense related genes were differentially altered by the PEEs of rooibos and honeybush in rat liver and further indicated potential oxidative stress. Modulatory effects of PEEs on expression of 84 of these genes in rat liver were assessed with a quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) array and provided additional insights into the possible adverse and protective effects of rooibos and honeybush. Further investigation on total polyphenol dose levels and time of exposure in the application of PEEs of rooibos and honeybush as dietary supplements and functional foods is recommended and will also be of value in anticipated regulatory requirements for future substantiation of safety and efficacy. / AFRIKAANSE OPSOMMING: Die moontlike voordelige en/of nadelige modulerende effekte van polifenol-verrykde ekstrakte van rooibos (Aspalathus linearis) en heuningbos (Cyclopia spp.) op die antioksidant homeostasis in die lewer is ondersoek. Die fase II metaboliete van aspalatien en mangiferin, die hoof verbindings in rooibos en heuningbos onderskeidelik, is ondersoek t.o.v. glukuronidering en sulfonering. Glukuronidasie het gelei tot n verlies in antioksidant aktiwiteit van aspalatien en mangiferin soos bepaal in post-kolom HPLC-DAD-DPPH• en HPLC-DADABTS•+ toetse, asook verminderde interaksie met yster van mangiferin in die FRAP toets. Twee onafhanklike studies van 28 en 90 dae is onderneem met polifenol-verrykde ekstrakte (PVEs) van ongefermenteerde rooibos [Aspalathus linearis (PVR)] en heuningbos [Cyclopia. subternata (PVCsub) and C. genistoides (PVCgen)] in manlike Fisher rotte om die moontlike voordelige en/of nadelige biologiese effekte te ondersoek. PECgen was slegs in die 28 dae studie ingesluit. PVEs is gekarrakteriseer deur in vitro antioksidant en HPLC analises. Die belang van chemiese karaktirisering van rooibos en heuningbos tydens ondersoeke na biologiese aktiwiteit is duidelik aangesien verskeie en variërende biologiese aktiwiteite en verskille in die komposisie in die huidige studie gesien is. Die biologiese parameters wat ondersoek is om die effek van die PVEs te bepaal het serum kliniese parameters, aktiwiteit van geselekteerde ensieme, glutatioon en evaluering van die ekspressie van oksidatiewe en antioksidant verwante gene in die lewer, ingesluit. Sub-kroniese (90 dae) blootstelling van rotte aan PVR en PVCgen het yster absorpsie negatief beïnvloed. Die beduidende (P<0.05) verlaagde vlak van gereduseerde glutatioon in die lewer was toegeskryf aan die hoë vlakke van polifenole ingeneem tydens die studie en word moontlik veroorsaak deur n spesifieke katekol o-konjugasie van GSH. Hierdie interaksie was ook moontlik die oorsaak van n beduidende (P<0.05) toename in die aktiwiteit van glutatioon reduktase. Dié bevindinge het moontlike implikasies t.o.v die glutatioon homeostase en is n moontlike indikase dat PVEs van rooibos kan bydra tot oksidatiewe stres. PVCsub het veranderinge in die lewer gal-sisteem tot gevolg gehad aangesien daar n beduidende (P<0.05) verhoging in die serum totale bilirubin en alkalien fosfaat was. Hierdie veranderinge is beïnvloed deur die ouderdom, vlakke van die totale polifenole en die periode van blootstelling. Die uitdrukking van oksidatiewe en antioksidant verwante gene is op verskillende maniere beïnvloed deur die PVEs van rooibos en heuningbos in rot lewer and dien as n verdere indikasie van onderliggende oksidatiewe stres. Die modulerende effekte van PVEs op geenuitdrukking het gelei tot additionele insig aangaande die moontlike skadelike of beskermende eienskappe van PVEs vir gebruik as kruie produkte of dieet aanvullings. Die indikasies van moontlike oksidatiewe stres was duidelik van biologiese parameters en modulering van geenuitdrukking in die lewer, en vereis verdere ondersoek na die polifenool dosis en periode van toediening voordat PVEs van rooibos en heuningbos as funksionele voedsel produkte gebruik word. Hierdie ondersoek sowel as toekomstige ondersoeke in hierdie verband sal van waarde wees vir regulatoriese vereistes omtrent die veiligheid en effektiwiteit van rooibos en heuningbos kruie produkte.