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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Chemical profiles of bush tea (Athrixia phylicoides DC.) at different phenological stages and as influenced by pruning and growth regulators.

Maudu, Mpho Edwin 12 1900 (has links)
Thesis(M.Sc)--University of Limpopo, 2010. / Bush tea (Athrixia phylicoides DC.) has received interest as another indigenous South African herbal tea with potential for commercialization. The success of commercialization of bush tea hinges on maintenance or enhancement of quality of bush tea as a herbal beverage. Herbal tea quality is one of the critical factors in commercialization that would determine the price of tea for local sale and export. A research was conducted to determine chemical profiles of bush tea at different phenological stages and as influenced by pruning and application of growth regulators. A trial to determine the quality of tea harvested at various phenological stages (namely new growth, older growth and whole plants) from wild and cultivated bush tea was conducted. This was to help determine the best phenological stage to harvest bush tea of best quality. In cultivated bush tea, harvested new growth or as whole plants proved to be of higher quality owing to their higher polyphenol and tannin attributes respectively. In wild bush tea, both new and older growth proved to be of good quality owing to the higher total polyphenol content and higher total antioxidants, respectively. A trial to determine the effect of pruning at different heights on growth and quality of bush tea was also conducted. Pruning of bush tea largely led to yield reduction. Unpruned tea plants remained the tallest plants, with higher number of branches, bigger leaf area and a larger biomass than apically, middle and base pruned bush tea plants. Pruning at different heights also proved to have little or no effect on quality of bush tea. While only total polyphenols remained higher in unpruned tea plants, no significant differences were observed in tannin and total antioxidant content in unpruned, apically, middle and base pruned tea plants. A third trial was conducted to investigate the effects of gibberellins on sprouting and quality of bush tea. The trial results showed that gibberellin application had a iv favourable effect on growth of bush tea, with application of 3% and 4% yielding the highest growth. The results also indicated a declining total polyphenol and antioxidant content with increasing gibberellin application rate, while tannins peaked at 2% application rate.
2

Seed germination and vegetative propagation of bush tea (athrixia phylicoides)

Araya, Hintsa Tesfamicael 09 February 2006 (has links)
Bush tea (Athrixia phylicoides) is an herbaceous plant of the Asteraceae family used throughout history as medicinal herbal tea by the people of South Africa. Many studies stated that the plant has an ability to be commercialized as a medicinal herbal tea. But vegetative propagation of this type of plant by stem cutting, survival ability of the rooted cuttings, response to different hormone concentrations and the requirement of the seeds for germination has not been studied. In this investigation, different features aimed at effective propagation of bush tea were studied. These comprised: cutting position (apical vs. basal), media (pine bark vs. sand), hormone (Seradix No. 2), season (summer, autumn, winter and spring), transplanting survival of rooted apical and basal cuttings, response of basal cuttings to three hormone concentration levels (Seradix No. 1, 2 and 3) and light and temperature requirement for bush tea seed germination. In vegetative propagation, apical cuttings rooted to higher percentage and produced high root number as well as longer roots than basal cuttings. Pine bark improved the number of roots developed but had no effect on rooting percentage as well as root length. Application of rooting hormone (Seradix No. 2) increased root numbers but not rooting percentage or root length. Rooting of cuttings was improved when propagated in autumn (longer roots) and spring (more number of roots) than in summer or winter. There was higher survival percentage (67.5%), high root number as well as longer roots from apical cuttings than from basal cuttings (50%) two months after transplanting. Propagation in pine bark with hormone application increased root number after transplanting. Application of hormone also improved root and shoot length after transplanting. Apical cuttings propagated in pine bark with hormone developed more number of roots. Cuttings propagated in sand with hormone and in pine bark without hormone also produced longer shoots after transplanting. Regarding response of basal cuttings to hormone concentration, high number of roots was produced in pine bark with Seradix No. 2 at 10 days after planting (DAP) but at 15 DAP more roots were produced in pine bark with Seradix No. 1. With sand, more roots were produced with Seradix No. 3 than Seradix No. 1 and 2. Number of roots were also higher with 0.3% IBA concentration (Seradix No. 2) and 0.1% IBA concentration (Seradix No. 1). Similarly, cuttings with lower IBA concentration (0.1%, Seradix No. 1) rooted to higher percentage followed with 0.3% IBA concentration (Seradix No. 2). Germination percentage of bush tea seeds differed with the temperature treatments and the highest was 75.5% at 20 and 25°C followed by 15°C with 64.5% and low percentage at 30 and 10°C with 36 and 47% respectively. There was a high germination percentage in constant temperatures than alternate temperatures and in continuous light than alternate light: dark or continuous dark. Germination percentage was also higher in continuous light at constant temperatures than with alternated light: dark with constant temperatures. In addition, there was more differences in germination percentage with variation in light exposure than variation in temperatures. At low temperature (10°C), longer time was required to start germination and germination rate was high at 20°C continuous light and low at 30:30°C alternate light: dark. Based on this investigation, better vegetative propagation and survival of bush tea can be attained from apical cuttings with Seradix No. 2 but basal cuttings rooted better with Seradix No. 1 in pine bark. Seeds germinated to higher percentage and rate at 20°C constant temperature and continuous light. / Dissertation (MSc (Agric) Horticulture)--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted
3

Effect of ultraviolet treatment on shelf life, various spoilage microorganisms and the physicochemical characteristics of rooibos iced tea

Monyethabeng, Moneah Mmabatho January 2015 (has links)
Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2015. / Rooibos iced tea (RIT), as one of the products of Rooibos is fast becoming very popular as a beverage in society due to the benefits of the phenolic compounds that are associated with this herbal tea. Some of the commercially available products have been found to contain, if any, lower contents of the major phenolic compounds, namely aspalathin and its oxidation products, iso-orientin and orientin. Their presence is considered as indicators of a good quality product. The purpose of this study was to investigate the effect of ultraviolet-C (UV-C) light as an alternative treatment to heat treatment on the shelf life, pH, phenolic composition, colour and microorganisms associated with Rooibos. Two formulations of RIT were used in order to determine the efficacy of the UV-C on the shelf life whilst three formulations were used for the physicochemical analysis. Only one formulation was used for inoculation with three spoilage bacteria, yeast and mould spoilage microorganisms namely; Escherichia coli K12, Staphylococcus aureus, Salmonella sp., Saccharomyces cerevisiae and Cladosporium sp. The UV-C dosages of 0, 918, 1 836, 2 754 and 3 672 J.l -1 were used to treat the RIT using a pilot-scale UV-C system with a turbulent flow at a constant flow rate of 4000 l.hr-1 . A log count of 4 log10 was considered the limit for the spoilage growth since it is the average log10 afternormal pasteurisation. The use of UV-C treatment was found to have significantly (p1) effect on the overall colour difference of the RIT in formulations A, B, and C. All the spoilage microorganisms were significantly reduced by UV-C dosage to less than 4 log10 except the Cladosporium sp. The S. cerevisiae was the most sensitive microorganism whilst Cladosporium sp. was the most resistant. The effect of UV-C on the spoilage microorganism followed the sequence: S. cerevisiae>Salmonella sp.>S. aureus>E. coli K12>Cladosporium sp. This study indicated that microbiological reduction was achieved as a function of increasing UV-C dosage. In order to achieve the highest log10 reduction, the highest UV-C dosage of 3 672 J.l-1 may be used. However, the dosage may need to be increased in order to achieve the desired results in the treatment of Cladosporium sp. It can thus be concluded from the above investigations that UV-C dosage treatment of 3 672 J.l-1 is optimum in the non-thermal treatment of RIT / South African Association for Food Science & Technology Cape Peninsula University of Technology Bursary
4

Sensory and phenolic profiling of Cyclopia species (Honeybush) and optimisation of the fermentation conditions

Theron, Karin Alicia 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The sensory profiles, phenolic composition and colour of honeybush infusions, prepared from six Cyclopia species (C. sessiliflora, C. longifolia, C. genistoides, C. intermedia, C. subternata and C. maculata), were determined to establish the variation between species. The results of the sensory study were used to create a honeybush sensory wheel and lexicon. The “characteristic” sensory profile of honeybush tea can be described as a combination of floral, sweet, fruity and plantlike flavours with a sweet taste and a slightly astringent mouthfeel. Sensory results indicated that the species could be divided into three distinct groups; group A (C. sessiliflora, C. intermedia and C. genistoides), group B (C. longifolia and C. subternata) and group C (C. maculata). Group A was associated with fynbos floral, fynbos sweet and plantlike attributes, group B with rose geranium and fruity sweet attributes and group C with woody, boiled syrup and cassia/cinnamon attributes. Gas chromatography-olfactometry analysis of the C. maculata aroma fraction indicated that the spicy note of its aroma could possibly be explained by the high concentration of the volatile component eugenol. However, none of the aroma impact volatiles had a specific cassia/cinnamon note. Large variation in the composition of the honeybush infusions was revealed through the quantification of the soluble solids, total polyphenol and individual monomeric polyphenolic compounds, as well as the absorbance (“colour”). Infusions of C. genistoides, C. longifolia and C. sessiliflora had the highest soluble solids and total polyphenol content, as well as the highest absorbance values. Only mangiferin, isomangiferin, hesperidin and compound C (unidentified compound) were detected in all six Cyclopia species. Cyclopia genistoides, C. longifolia and C. sessiliflora, in order of prominence, contained the highest concentration of both mangiferin and isomangiferin whereas C. genistoides and C. maculata contained the highest hesperidin content. The bitter taste present in certain Cyclopia species appeared to be due to a high mangiferin content, however, compounds such as isomangiferin and compound C might also have played a role. The effect of fermentation (oxidation) temperature (80°C and 90°C) and time (8 h, 16 h, 24 h and 32 h) of C. genistoides, C. subternata and C. maculata on the sensory characteristics of their infusions was also investigated. Fermentation for longer than 8 h resulted in an increase in positive sensory attributes and a decrease in negative sensory attributes rather than the formation of new sensory attributes. A fermentation temperature/time combination of 80°C/24 hours or 90°C/16 h was required for C. genistoides, C. subternata and C. maculata. Fermenting C. genistoides at 90°C would result in a honeybush infusion with slightly less rose geranium notes whereas C. subternata can be fermented at either 80°C or 90°C, depending on whether floral or apricot jam notes are desired. Cyclopia maculata should preferably not be fermented at 90°C due to an increase in negative sensory attributes (hay/dried grass and green grass). Fermentation reduced the soluble solids content, total polyphenol content, colour and concentration of individual polyphenolic compounds. Changes in the taste and mouthfeel of honeybush tea could be attributed to changes in the polyphenolic composition caused by the high temperature oxidation. Mangiferin associated with the bitter taste of C. genistoides, while in C. subternata astringency may be partly attributed to the mangiferin and isomangiferin content. The study substantiated the need for further research on the contribution of the major phenolic compounds towards the taste and mouthfeel of Cyclopia species. / AFRIKAANSE OPSOMMING: Die sensoriese profiel, fenoliese samestelling en kleur van heuningbostee, berei van ses Cyclopia spesies (C. sessiliflora, C. longifolia, C. genistoides, C. intermedia, C. subternata en C. maculata), is bepaal ten einde die mate van variasie vas te stel. Die resultate van die sensoriese studie is gebruik om 'n sensoriese wiel en leksikon vir heuningbostee te ontwikkel. Die “karakteristieke” sensoriese profiel van heuningbostee kan beskryf word as 'n kombinasie van blomagtig, soet, vrugtig en plantagtige geure met 'n soet smaak en 'n effense frankheid. Sensoriese resultate het aangedui dat die spesies in drie groepe verdeel kon word; groep A (C. sessiliflora, C. intermedia and C. genistoides), groep B (C. longifolia and C. subternata) en groep C (C. maculata). Groep A is met fynbos blom, fynbos-soet en plantagtige geure geassosieer, groep B met roos geranium en vrugtige-soet geure en group C met houtagtige, gekookte stroop en kassia/kaneel geure. Gaschromatografie-olfaktometrie analises van C. maculata se aroma fraksie het getoon dat die speseryagtige aroma moontlik as gevolg van die hoë konsentrasie van die vlugtige komponent, eugenol, kon wees. Geen van die aroma-impak vlugtige verbindings het egter 'n spesifieke kassia/kaneelagtige noot gehad nie. Groot variasie in die samestelling van heuningbostee ten opsigte van die inhoud van oplosbare vastestowwe, totale polifenole en monomeriese fenoliese verbindings, asook die absorbansie (“kleur”) is aangetoon. Heuningbostee berei van C. genistoides, C. longifolia en C. sessiliflora het die hoogste oplosbare vastestowwe en totale polifenol inhoud, asook die hoogste absorbansie waardes gehad. Slegs mangiferien, isomangiferien, hesperidien en verbinding C (ongeïdentifiseerde verbinding) is in al ses Cyclopia spesies geïdentifiseer. Cyclopia genistoides, C. longifolia en C. sessiliflora, in volgorde van belangrikheid, het die hoogste konsentrasie van beide mangiferien en isomangiferin gehad teenoor C. genistoides en C. maculata wat die hoogste hesperidien konsentrasie gehad het. Die bitter smaak teenwoordig in sekere Cyclopia spesies blyk moontlik as gevolg van die hoë mangiferien inhoud te wees, hoewel komponente soos isomangiferien en komponent C dalk ook 'n rol mag speel. Die effek van die fermentasie temperatuur (80°C en 90°C) en tyd (8 h, 16 h, 24 h en 32 h) van C. genistoides, C. subternata en C. maculata op die sensoriese eienskappe van heuningbostee is ondersoek. Fermentasie vir langer as 8 h het tot 'n toename in positiewe sensoriese eienskappe en afname in negatiewe sensoriese eienskappe gelei eerder as die ontstaan van nuwe sensoriese eienskappe. Om heuningbostee met 'n optimum sensoriese profiel te verkry is 'n fermentasie temperatuur/tyd kombinaise van 80°C/24 h of 90°C/16 h nodig vir C. genistoides, C. subternata en C. maculata. Cyclopia genistoides wat by 90°C gefermenteer word sal minder van die roos geranium note bevat, terwyl C. subternata by 80°C of 90°C gefermenteer kan word, afhangende of 'n blomagtige of 'n appelkooskonfyt noot verlang word. Fermentasie by 90°C word nie aanbeveel C. maculata nie as gevolg van die toename van sekere negatiewe sensoriese eienskappe (hooi/droe gras aroma en -geur en groen gras aroma). Fermentasie het die inhoud van oplosbare vastestowwe, totale polifenole, individuele polifenoliese verbindings, asook kleur verminder. Veranderinge in die smaak en mondgevoel van heuningbostee kon toegeskryf word aan die veranderinge in die polifenoliese inhoud as gevolg van die hoë temperatuur oksidasie. Mangiferien is met die bitter smaak van C. genistoides geassosieer, terwyl mangiferien and isomangiferien moontlik deels frankheid in C. subternata veroorsaak. Die studie het die noodsaaklikheid vir verdere navorsing op die bydrae van die hoof fenoliese verbindings tot die smaak en mondgevoel van Cyclopia spesies gestaaf.
5

BIOMASSA E NUTRIENTES EM PLANTIOS DE ERVA-MATE (Ilex paraguariensis A. St.-Hil.), NO MUNICÍPIO DE NOVA PRATA, RS / BIOMASS AND NUTRIENTS IN HERBAL TEA (Ilex paraguariensis A. St.-Hil.) STANDS, IN NOVA PRATA COUNTY, RS

Berger, Gabriel 23 October 2006 (has links)
This study had as objective to quantify the total herbal tea biomass, to quantify the biomass produced in harvesting, to determine the nutrients amount in biomass compartments, to quantify the exported nutrients in herbal tea harvesting and to adjust mathematic models to quantify, due to equations, the harvest, residual and total biomass. Thirty plots were evaluated, totalizing 306 trees, where each circular plot had 44,18 m2 as area. In these plots, the biometric variables of each tree were measured: total height (ht), trunk diameters at 0,60 m above the soil (d 0.6 meters), height from the first branch or trunk, live crown lenght and crown projection rays. The harvest biomass, composed by leaves, stems and residue was evaluated too. After that, a plant located outside the plot was evaluated, that had the average dendrometric characteristics as the ones included in the plots. Later, each tree was cut at soil level, the leaves and stems, residues, wood, bark and roots weight were determined. The above ground biomass plus the roots biomass consisted in total biomass. The samples taken were dried in an oven to dry biomass and nutrients amount determination. The equations to estimate biomass, were done through SAS System version 8. The Stepwise method of independent variables selection was used, where at maximum 3 variables were included in the selected equations, and the partial R2 from the independent variable was higher to 1% to be considerable significant. The selection test from equations was done with and without intercept. The results showed by the equations without intercept were higher, being rejected these last ones. The nutrients amount determination was done in leaves and stem, wood, residues, bark and roots dried matter. The average fresh and dried biomass plus stems, sampled in the 30 units in kg/tree and kg/ha were: 7,849; 18577,34; 3,081; 7585,22 respectively. The average fresh and dried biomass residues in the 30 units in kg/tree and kg/ha were: 2,583; 6195,71; 1,009; 3052,01. The average fresh and dried leaves and stems biomass sampled in the 30 felled trees in kg/tree were: 7,713 and 3,174 respectively. The average fresh and dried biomass residues, sampled in 30 felled trees in kg/tree were: 2,708 and 1,358 respectively. The average fresh and dried biomass in wood, sampled in the 30 felled trees in kg/tree were: 13,609 and 6,785 respectively. The average fresh and dried roots biomass, sampled in the 30 felled trees were: 7,678 and 4,693 respectively. The total average fresh biomass per felled tree in kg/tree was 33,135. The total average dried biomass in kg/tree was 16,857. The estimated equations for different herbal tea dried biomasses were: wood biomass = 0.28329.rm + 0.07082.dh2; bark biomass =0,44728.lnm + 1,33596.im2; root biomass=2,32270.lnm + 12,81476.im2; residues biomass=0,34026.m 2,61245*ln2m + 0,43581.rm; leaves plus stems biomass=0,56043.ac + 2,06004.ln2d; total biomass=11,29406.rm + 0,10522.dh2. The total stand dried biomass was 41.078,03 kg/ha, being distributed: 16.654,49 kg/ha in the wood; 11.973,01 kg/ha in the roots; 7.582,22 kg/ha in leaves plus stems; 3.052,01 kg/ha in residues and 2.113,30 kg/ha in the bark. The macronutrients exported outside the stand follow this order: nitrogen > potassium > calcium > magnesium > sulphur > phosphorus. The components that show the higher amounts per hectare are: leaves plus stems (404,26 kg/ha), followed by roots (313,50 kg/ha), wood (149,93 kg/ha), residue (104,75 kg/ha) and bark (93,16 kg/ha). The micronutrients exported followed this order: iron > manganese > zinc > boron > cupper. The compartments that show the higher amounts per hectare are: roots (19,31 kg/ha), followed by leaves plus stems (6,43 kg/ha), wood (2,50 kg/ha), bark (2,24 kg/ha) and residues (1,08 kg/ha). / Este trabalho teve como objetivos estimar a biomassa total da erva-mate, produzida na colheita, determinar a concentração de nutrientes nos componentes da biomassa, quantificar os nutrientes exportados na colheita da erva-mate e ajustar modelos matemáticos que quantificassem por meio de equações a biomassa de colheita, residual e total. Inicialmente foram avaliadas trinta parcelas circulares, sendo que cada parcela possuía uma área de 44,18m2. Foram amostradas no total 306 árvores. Nessas parcelas, foram medidas as seguintes variáveis biométricas de cada planta: altura total em metros (ht), diâmetro dos troncos a 0,60 metros acima do solo (d 0.6 metros), raio médio de copa em metros, área de copa em metros quadrados, comprimento médio de copa em metros e avaliou-se a biomassa de colheita composta de folhas mais talos e biomassa residual. Em seguida, em cada parcela amostrada foi avaliada uma planta situada fora desta, que apresentou a média das características dendrométricas das árvores incluídas nas parcelas. Nessas 30 árvores foram determinadas novamente as variáveis biométricas e biomassa de colheita e residual Após isto cada árvore foi decepada ao nível do solo, determinando o peso verde de madeira, casca e raiz . A biomassa área acrescida da biomassa de raízes constitui a biomassa total. Posteriormente retirou-se amostras verdes, de folhas mais talos, resíduos, madeira, casca e raiz as quais foram secadas em estufa, para posterior determinação da biomassa e a concentração de nutrientes. A construção das equações para estimar a biomassa, utilizouse o pacote estatístico Sas System versão 8 . Foi utilizado o método Stepwise de seleção de variáveis independentes, em que se limitou ao máximo a inclusão de três variáveis nas equações selecionadas, e o R2 parcial da variável independente superior a 1% para considerá-la significativa. O teste de seleção de equações foi realizado com e sem intercepto. Os resultados apresentados pelas equações sem intercepto foram superiores às equações com intercepto, tendo sido então desprezado esses últimos. A determinação do teor de nutrientes foi realizada na matéria seca de folhas mais talos, madeira, resíduos, casca e raiz. A biomassa média verde e seca de folhas mais talos, amostradas nas 30 unidades amostrais em kg/árvore e kg/ha foram respectivamente: 7,849; 18577,34; 3,081; 7585,22. A biomassa média verde e seca de resíduos nas 30 unidades amostrais em kg/árvore e kg/ha foram respectivamente: 2,583; 6195,71; 1,009; 3052,01. A biomassa média verde e seca de folhas mais talos, amostradas nas 30 árvores abatidas em kg/árvore foram respectivamente: 7,713 e 3,174. A biomassa média verde e seca de resíduos, amostradas nas 30 árvores abatidas em kg/árvore foram respectivamente: 2,708 e 1,358. A biomassa média verde e seca de madeira, amostradas nas 30 árvores abatidas em kg/árvore foram respectivamente: 13,609 e 6,785. A biomassa média verde e seca de casca, amostradas nas 30 árvores abatidas em kg/árvore foram respectivamente: 1,427 e 0,847. A biomassa média verde e seca de raiz, amostradas nas 30 árvores abatidas em kg/árvore foram respectivamente: 7,678 e 4,693. A biomassa total média verde por árvore abatida em kg/árvore foi de 33,135. A biomassa total média seca por árvore abatida em kg/árvore foi de 16,857. As equações estimadas para as diferentes biomassas secas da erva-mate foram as seguintes: biomassa de madeira = 0,28329.rm + 0,07082.dh2; biomassa de casca = 0,44728.lnm + 1,33596.im2; biomassa de raiz = 2,32270.lnm + 12,81476.im2; biomassa de resíduos = 0,34026.m 2,61245*ln2m + 0,43581.rm; biomassa de folhas mais talos = 0,56043.ac + 2,06004.ln2d; biomassa total = 11,29406.rm + 0,10522.dh2. A biomassa seca total do povoamento foi de 41.078,03 kg/ha, sendo assim distribuídas madeira 16.654,49 kg/ha; raízes 11.973,01 kg/ha; folhas mais talos 7.582,22 kg/ha; resíduos 3.052,01 kg/ha e casca com 2.113,30 kg/ha. Os macronutrientes exportados do povoamento obedecem a seguinte ordem: nitrogênio > potássio > cálcio > magnésio > enxofre > fósforo. Os componentes que apresentam as maiores quantidades de macronutrientes por hectare são: folhas mais talos (404,26 kg/ha), seguido pela raiz (313,50 kg/ha), madeira (149,93 kg/ha), resíduo (104,75 kg/ha) e por último a casca (93,16 kg/ha). Os micronutrientes exportados do povoamento obedece à seguinte ordem: ferro > manganês > zinco > boro > cobre. Os componentess que apresentam as maiores quantidades de micronutrientes por hectare são: raiz (19,31 kg/ha), seguido pela folhas mais talos (6,43 kg/ha), madeira (2,50 kg/ha), casca (2,24 kg/ha) e por ultimo os resíduos (1,08 kg/ha).
6

Stanovení aktivních látek v instantních nápojích určených pro dětskou výživu / Analysis of active substances in instant beverages for child´s nutrition

Jašková, Martina January 2011 (has links)
The aim of presented diploma thesis was to characterize baby beverages for early infant feeding. Theoretical part deals with baby foods and beverages including breast milk. Practical part is focused on analysis of active substances in 21 commercially available fruit and herbal instant granular baby beverages and in 3 packaged tea bags for infant and toddler age. To evaluation of antioxidant properties some group parameters were used - total polyphenols, total flavonoids, total antioxidant activity and anthocyanins. All of them were analysed by using spectrophotometrical methods. For identification and quantification of individual phenolic substances was used RP-HPLC/UV-VIS and HPLC/PDA/LC-MS, identification of individual mono- and disaccharides was performed by HPLC/RI. L-ascorbic acid supplemented to some children's drinks was analysed by HPLC-NH2/UV. Protein analysis was performed by Experion microfluidic electrophoresis system (BioRad) and protein concentration was verified by colorimetric method. In general, the highest content of phenolic compounds was shown in tea bags when compared with instant granular beverages that contain mostly added simple carbohydrates. Using contact microbial tests proved immediately after opening and also during manipulation with tea boxes was verified that analysed baby teas are in agreement with strict hygiene requirements for baby beverages.
7

Potential neuroprotective effects of fermented rooibos herbal tea in a rat model of ischemic brain injury

Akinrinmade, Olusiji Alex January 2015 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Stroke is the third leading cause of death in South Africa, killing about 240 people a day and leaving survivors with residual disabilities. There is no clinically approved neuroprotective agent for stroke at the moment but the consumption of plant polyphenols has been suggested to offer neuroprotection against stroke and other neurodegenerative diseases. In this study, we investigated the effects of long term consumption of fermented rooibos herbal tea (FRHT) on ischemia reperfusion brain injury (I-RBI) in rats. Male adult Wistar rats were fed FRHT ad libitum for 7 weeks prior to the induction of ischemic injury by the transient bilateral occlusion of the common carotid arteries (BCCAO) for 20 minutes followed by 24 hours, 4 and 7 days of reperfusion respectively. Rats were then evaluated for neurologic deficits before sacrifice and brains harvested for assessment of brain oedema, blood-brain-barrier (BBB) integrity through Evans blue extravasation (EBE), immunohistochemical studies of apoptosis and lipid peroxidation. Oxygen radical antioxidant capacity and ferric reducing antioxidant power assays were also conducted to assess total antioxidant capacity after ischemia-reperfusion injury. Notably, the long term consumption of fermented rooibos herbal tea prevented brain oedema by reducing cerebral swelling induced by I-RBI. We also observed that fermented rooibos herbal tea offered neuroprotection against damage to the BBB and delayed neuronal death associated with BCCAO as fewer apoptotic cells were identified 7 days post BCCAO reperfusion. Significantly reduced levels of lipid peroxidation and increased levels of total antioxidant capacity were also observed in brain specimens of rats treated with FRHT. Rats treated with FRHT also showed improved neurologic outcomes when compared with the untreated animals. Our results show that FRHT has potent antioxidant and anti-inflammatory properties which can provide neuroprotective effects against neuronal cell loss, cerebral swelling, BBB disruption, lipid peroxidation and neurologic deficits following I-RBI. The use of FRHT is therefore highly recommended for patients with conditions that predispose them to stroke.
8

The effect of Cyclopia maculata on lipogenesis and lipolysis in 3T3-L1 preadipocytes and adipocytes

Dudhia, Zulfaqar 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / Includes bibliography / ENGLISH ABSTRACT: Obesity is a major source of morbidity and mortality worldwide. More than 1.5 billion individuals over the age of 20 years are overweight, with more than 500 million of these individuals being obese. Obesity increases the risk of developing cardiovascular disease, type 2 diabetes and certain types of cancer. Recently, a number of plant extracts have been shown to possess anti-obesity properties in vitro and in various animal models of obesity. The aim of this study was to investigate the effect of a hot water fermented extract of Cyclopia maculata, a South African herbal tea more commonly referred to as honeybush, on lipogenesis and lipolysis in 3T3-L1 pre-adipocytes and adipocytes. To investigate the effect of C. maculata extract on adipogenesis, 3T3-L1 preadipocytes were differentiated in adipogenesis inducing media containing various concentrations. The optimal concentration was determined by screening concentrations ranging from 0 to 1,600 μg/ml. 3T3-L1 pre-adipocytes were differentiated with TNFα or unsupplemented adipogenesis inducing media as positive and negative controls, respectively. Intracellular lipid accumulation was measured by using the Oil O Red stain and a commercial triglyceride assay kit. Cell viability was measured using the 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) and adenosine tri-phosphate (ATP) assays. The expression of PPARγ, C/EBPα, SREBP-1 and PPARα was assessed by Western blot analysis, while the expression of the secreted proteins leptin and adiponectin was assessed by ELISA. The effect of C. maculata extract on lipolysis was investigated by differentiating 3T3-L1 pre-adipocytes in adipogenesis inducing and adipogenesis maintenance media for 8 days until they were mature adipocytes, and thereafter treating with C. maculata extract for 24 hours. The optimal concentration was determined by screening concentrations ranging from 0 to 1,600 μg/ml. Isoproteronol or unsupplemented adipogenesis maintenance media was used as positive and negative controls, respectively. Intracellular lipid break down was measured by using the Oil O Red stain, while glycerol release, a marker of lipolysis, was measured using a commercial kit. Cell viability was measured using the MTT and ATP assays. The expression of HSL and perilipin was assessed by Western blot analysis, while the expression of secreted proteins leptin and adiponectin was assessed by ELISA. Treatment with the C. maculata extract, at most of the concentrations tested, decreased intracellular lipid accumulation in pre-adipocytes. The Oil O Red and the intracellular triglyceride assay, in combination with the cell viability assays, showed that 80 μg/ml optimally reduced intracellular lipid without affecting cell viability. Western blot analysis showed that differentiation of 3T3-L1 adipocytes in the presence of 80 μg/ml of the C. maculata extract decreased the expression of PPARγ2, a key adipogenenic transcription factor, 1.8-fold (p=0.006). PPARγ2 was observed at a smaller size than expected and further studies are needed. The results of the C/EBPα, SREBP-1 and PPARα Western blots were not included in this study and are recommended to be further optimized to reduce non-specific binding. ELISA results showed a significant increase in the secretion of the adipokines, adiponectin (>10-fold, p<0.001) and leptin (1.5-fold, p=0.002). The C. maculata extract was better than the positive control, TNFα, at inhibiting adipogenesis. A concentration of 80 μg/ml of the C. maculata extract maximally induced lipolysis, without affecting cell viability. Western blot analysis showed non-specific binding, and are recommended to be further optimized to reduce non-specific binding. Western blot analysis also showed that acute treatment (24 hours) of mature 3T3-L1 adipocytes with 80 μg/ml increased the expression of the lipolytic protein, HSL (1.6-fold, p=0.025). Perilipin Western blot was not included due to non-specific binding. ELISA results showed an increase in adiponectin (1.5-fold, p=0.015) and leptin (1.2-fold, p=0.067) secretion. Similar results were obtained after treatment with the C. maculata extract or the positive control, isoproteronol. This study shows that treatment of 3T3-L1 pre-adipocytes and adipocytes with 80 μg/ml of C. maculata plant extract inhibits adipogenesis and induces adipolysis, without causing cytotoxicity. A major limitation of the current study is that it was conducted in an in vitro model and does not represent the complexity of obesity as it occurs in humans. However, despite this, we believe that these results are promising and provide support for future in vivo studies to substantiate these preliminary findings. The results of this study is aligned with the Department of Science and Technology’s Ten Year Innovation Plan and the “Farmer to Pharma” value chain that aims to improve our bio-economy by developing our indigenous resources. Moreover, this type of initiative will be able to stimulate job creation, while being able to utilize the very rich South African indigenous knowledge. / AFRIKAANSE OPSOMMING: Vetsug is 'n groot oorsaak van morbiditeit en mortaliteit wêreldwyd. Tans is meer as 1,5 miljard mense oor die ouderdom van 20 jaar oorgewig, met meer as 500 miljoen van hierdie individue wat vetsugtig is. Vetsug verhoog die risiko vir die ontwikkeling van kardiovaskulêre siekte, tipe 2 diabetes en sekere soorte kanker. Onlangs het 'n aantal plantekstrakte anti-vetsug eienskappe in vitro en in verskeie dier modelle van vetsug getoon. Die doel van hierdie studie was om die effek van die Cyclopia maculata, 'n Suid-Afrikaanse kruie-tee, meer algemeen bekend as heuningbos, op lipogenese en lipolise in 3T3-L1 pre-adiposiete en adiposiete te ondersoek. Vir die ondersoek, is 3T3-L1 pre-adiposiete gedifferensieer in ‘n adipogeneseinduserende media met verskillende konsentrasies van ‘n warm water ekstrak van gefermenteerde C. maculata. Die optimale konsentrasie van C. maculata ekstrak is bepaal deur die selle met verskeie konsentrasies te behandel wat gewissel het van 0 tot 1600 mg / mL. 3T3-L1 pre-adiposiete is met adipogenese-induserende media gedifferensieer met of sonder TNFα supplementasie wat as positiewe en negatiewe kontrole, onderskeidelik gedien het. Intrasellulêre lipied-versameling is gemeet deur middel van Oil O Red kleuring en trigliseried-inhoud is bepaal deur 'n kommersiële kit. Sel-lewensvatbaarheid is bepaal deur 3-(4,5-Dimetielthiazol-2- yl)-2,5-difenieltetrazolium bromied (MTT) en adenosien tri-fosfaat (ATP) assays. Die PPARγ, C/EBPα, SREBP-1 and PPARα proteïen uitdrukking is deur middel van Western-blot analise bepaal, terwyl die gesekreteerde proteïene, leptien en adiponektien, deur ELISA bepaal is. Die effek van C. maculata ekstrak op lipolise is ondersoek deur 3T3-L1 preadiposiete in adipogenese-induserende media te differensieer waarna die selle vir ‘n verdere 8 dae in adipogenese-onderhoud media gekultuur is totdat hulle volwasse adiposiete bereik het, voordat die adiposiete behandel is met C. maculata ekstrak vir 24 uur. Die optimale konsentrasie C. maculata ekstrak is bepaal deur die selle met verskeie konsentrasies te behandel wat gewissel het van 0 tot 1600 mg/ml. Adipogenese-onderhoud media met of sonder isoproterenol is onderskeidelik gebruik as die positiewe en negatiewe kontroles. Intrasellulêre lipied afbraak is deur middel van Oil O Red gemeet, terwyl vry gliserol, 'n merker van lipolise, deur ‘n kommersiële kit bepaal is. Sel-lewensvatbaarheid is bepaal deur MTT en ATP assays. Die uitdrukking van HSL is deur middel van Western-blot analise bepaal, terwyl die uitdrukking van die gesekreteerde proteïene, leptien en adiponektien, deur ELISA gemeet is. Ek stel voor dat die perilipin Western blots verder geoptimaliseer word om sodoende nie-spesifieke binding te verminder. Behandeling met C. maculata ekstrak het intrasellulêre lipied-akkumulasie in die pre-adiposiete verminder, by die meeste van die konsentrasies wat getoets is. Die Oil O Red en die intrasellulêre trigliseried toetse, in kombinasie met die sellewensvatbaarheid assays, het getoon dat 80 mg/ml C. maculata ekstrak intrasellulêre lipied optimaal verminder sonder om die sel-lewensvatbaarheid te affekteer. Western blot analise het getoon dat die differensiasie van 3T3-L1 adiposiete in die teenwoordigheid van 80 mg/ml C. maculata ekstrak die uitdrukking van PPARγ2, 'n sleutel adipogenetiese transkripsie faktor, 1.8-voudig (p=0.006) verlaag. PPARy2 is waargeneem by a kleiner grootte as verwag en verdere ondersoek word benodig. Ek stel voor dat die C/EBPα, PPARα en SREBP- 1 Western blots verder geoptimaliseer word om sodoende nie-spesifieke binding te verminder. ELISA resultate het 'n beduidende toename in die sekresie van die adipokines, adiponektien (>10-voudig, p <0.001) en leptien (1.5-voudig, p= 0.002) getoon. Cyclopia maculata ekstrak was beter as die positiewe kontrole, TNFα, om adipogenese te inhibeer. Teen ‘n konsentrasie van 80 mg/ml het C. Maculata ekstrak lipolise maksimaal geïnduseer, sonder om sel-lewensvatbaarheid te beinvloed. ELISA resultate het 'n toename in adiponektien (1.5-voudig, p = 0.015) en leptien (1.2-voudig, p = 0,067) sekresie getoon. Soortgelyke resultate is verkry met die positiewe kontrole, isoproteronol, as met C. maculata ekstrak behandeling. Hierdie studie het getoon dat die behandeling van 3T3-L1 pre-adiposiete en adiposiete met 80 mg/ml C. maculata ekstrak adipogenese inhibeer en adipolise induseer, sonder enige sitotoksisiteit. 'n Beperking van die huidige studie is dat dit in 'n in vitro model gedoen is wat nie die kompleksiteit van vetsug in die mens weerspieël nie. Ten spyte daarvan is resultate belowend en ondersteun dit toekomstige in vivo studies om hierdie voorlopige bevindinge te staaf. Bewys dat ‘n water ekstrak van gefermenteerde C. maculata anti-vetsug eienskappe het kan groot ekonomiese gevolge vir die heuningbos industrie inhou. Die resultate van hierdie studie is in lyn met die Departement van Wetenskap en Tegnologie se tien jaar Innovasie Plan en die "Farm Pharma" waardeketting wat daarop gemik is om ons bio-ekonomie te verbeter deur die ontwikkeling van ons inheemse hulpbronne. Daarbenewens sal hierdie tipe inisiatief potensieel werkskepping stimuleer, terwyl dit die ryk Suid-Afrikaans inheemse kennis aanwend.
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Die karakterisering, benutting en vervaardiging van produkte herwin vanuit Lippia scaberrima Sond. (Afrikaans)

Terblanche, Francois Cornelius 06 September 2001 (has links)
The genus Lippia Houst. (family Verbenaceae Juss.) has been used medicinally for centuries in various cultures. Numerous traditional medicinal applications of the South African Lippias are known, and among these is Lippia scaberrima Sond., the "Beukesbossie". Products recovered from L. scaberrima include essential oils by means of batch microwave distillation and a herbal tea manufactured by various methods. Microwave heating occurs through direct absorbtion of input energy. The whole sample is heated simultaneously with a heating rate much faster than for water distillation. Microwave distillation times can be expected to be less than corresponding water distillation times. A large number of parameters influence essential oil composition and yield. Various geographical, climatic, botanical, production and other parameters were identified and listed. The natural distribution of airdried leaves and flower heads and water as solvent was used in a domestic type microwave oven. Microwave distillation production parameters were studied and optima determined with respect to maximum oil yield. The batch microwave distillation production parameters studied (irradiation time, ratio of water used to plant material used, plant material moisture content, solvent recycling, physical size of plant material, addition of a surface tension modifier, soaking as pretreatment, load size, distillation kinetics and alternative solution medium namely ethanol) lead to a better understanding of microwave essential oil production. It enabled design of prototype continuous microwave distillation apparatus. Mobile, continuous microwave distillation equipment enables extraction of essential oils in a rural environment. It allows rapid investigation of a large variety of plants, and retrieval of essential oils in an economical and uncomplicated manner. Water distillation represents a classical technique for essential oil retrieval whereas microwave distillation is probably the most modern method. Physical and chemical properties of microwave and water distilled oils were determined. This enabled comparison of the microwave technique to a standard, industrially accepted production method. Tea was manufactured from L. scaberrima by means of the green tea, Rooibos tea and black tea methods as a first iteration in the production of a commercial tea. Drying curves was developed as well as appropriate regions of production variables like withering- and fermentation temperatures and times. / Dissertation (PhD(Ing.Chem))--University of Pretoria, 2002. / Chemical Engineering / unrestricted
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Obsah antioxidačních látek ve vybraných druzích ovocných a bylinných čajů / Antioxidative substances in selected fruit and herbal teas

Tomková, Martina January 2008 (has links)
This diploma project deals with antioxidant and antimutagenic properties of selected herbal and fruit teas commonly used in Czech population. Influence of different tea packaging (bag teas and loose leaf teas) on bioactive compound content was compared. Further, effect of long-term storage in common household conditions was studied. Antioxidant properties of teas were characterized using some group parameters - total antioxidant activity ("Randox Total Antioxidant Status Kit"), total phenolics and total flavonoids - as well as some individual representatives of low molecular weight antioxidants. Higher antixidant content was found in herbal teas than in fruit teas. Comparing bag teas with loose leaf teas higher antioxidant activity was shown in loose leaf teas. Individual antioxidants were analyzed using HPLC method with spectrophotometric detection and verified by on-line LC/MS. IN all tea samples catechins - catechin, epicatechin, epicatechin gallate and other flavonoids - rutin, morin, quercetin, kaempferol, myricetin and luteolin were determined. In most of teas high level of catechin and rutin was detected. The highest level of flavonoids was determined in herbal poured teas. Ascorbic acid content was also determined by HPLC method. Higher vitamine C level was found in most of fruit teas and in rose hip tea. Antimutagenicity of tea extracts was tested by in vitro test using Saccharomyces cerevisiae D7 yeast. High antimutagenic activity showed mainly nettle tea, tutsan tea and most of fruit teas. During long-term storage (1 year, 20°C, darkness) a significant decrease of all analyzed antioxidant parameters was followed. Higher lost of antioxidants was found in fruit teas when compared with the herbal ones.

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