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The antimicrobial and associated antioxidant activity of rooibos (aspalathus linearis) and honeybush (cyclopia intermedia) herbal teasDube, Phumuzile January 2015 (has links)
Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2015. / The increase in antibiotic resistant bacterial and fungal infections and the prevalence of oxidative stress-related conditions including cancers, cardiovascular diseases and diabetes has led to a consensus among pharmaceutical companies, clinicians and researchers that novel antimicrobial and antioxidant approaches are needed. These should be ideally efficacious, non toxic, easily accessible and affordable. There has been an increased interest in the identification of medicinal plants that possess both these bioactivities in an intrinsically related manner, allowing the simultaneous prevention of these ailments. Two South African herbal teas, rooibos and honeybush have been associated with a long history of medicinal use, hence their consideration for the current study. Numerous studies have been performed to evaluate the antioxidant activities of these South African herbal teas, however limited information about their antimicrobial activity currently exists. / National Research Foundation
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Effect on the total antioxidant capacity of substituting water with rooibos herbal teas in popular soup recipesOtty, Caralyn May January 2010 (has links)
Thesis (MTech(Food and Nutrition))--Cape Peninsula University of Technology, 2010 / Oxidative stress had been linked to the development of certain chronic diseases, but can be
delayed or prevented by the consumption of dietary antioxidants. Fruits, vegetables, wholegrains
and beverages, such as, teas are the major dietary antioxidant contributors. The majority of
South Africans do not consume adequate daily servings of fruits and vegetables, neither
sufficient minimally processed grains nor wholegrains. One way to incorporate antioxidants in
the South African diet is by adding antioxidant-rich foods or beverages to recipes as ingredients.
The objective of this study was to determine the effect on the total antioxidant capacity (TAC) of
substituting water with rooibos herbal tea in soup recipe formulations. Rooibos is a proudly
South African beverage rich in antioxidants. Soup is a readily available and relatively
inexpensive meal item regularly consumed during the winter months in South Africa. Three
popularly consumed soups in the City of Cape Town Metropolitan Municipality namely chunky
vegetable, butternut and chicken noodle were selected for the experimental study.
The water in each of the soup recipe formulations (control) was substituted with fermented and
unfermented / “green” rooibos (experimental recipe formulations). The study was of comparative
nature as the results (i.e. the TAC as the factor investigated) of three different soup recipe
formulations on fluid manipulations of each (with fermented and unfermented rooibos) was
compared to the control soup recipe formulations of each (no fluid manipulation). The results
(i.e. the TAC) of the three prepared control and experimental soup recipe formulations were also
compared to that of the raw soup mixtures of each of the soup recipe formulations to determine
the effect of thermal processing on each.
The main variable identified in the preparation of the soup recipe formulations that may impact
the TAC (the dependent variable) and needed to be controlled was the heat application. Other
variables that may influence the results were the soup recipe formulation ingredients, the prepreparation
of the raw ingredients, the standing time of ingredients before use and the
equipment used. Before determination of the heat applications and the fixed time allocations of
the soup recipe formulations to ensure recipe standardisation, the pre-preparation procedures of
the raw recipe ingredients were also standardised.
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Pharmacognostic studies on Herba OldenlandiaeLiang, Zhitao 01 January 2007 (has links)
No description available.
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Bioactivity and microbial content of Lippia multiflora leaves, a herbal tea from GhanaArthur, Hanson 12 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The consumption of herbal teas is an increasing phenomenon among tea consumers globally. However, herbal teas that are not pre-treated to reduce their microbial load are a health risk to consumers, in spite of their potential health-promoting properties. The aim of this study was to develop a steam pasteurisation treatment to reduce the microbial load on Lippia multiflora Moldenke (Verbanaceae) tea leaves, a herbal tea from Ghana, identify the bacteria present, and to evaluate the effect of the steam treatment on the bioactive constituent of the leaves.
An HPLC method was developed and optimised for the identification and quantification of verbascoside, the major antioxidant compound of L. multiflora herbal infusion. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used to confirm the presence of the compound in the infusion. Ascorbic acid was used as a stabilising agent during the quantification process to prevent the degradation of verbascoside. The hot water infusion of L. multiflora was compared to those of Aspalathus linearis (rooibos) and Cyclopia spp. (honeybush) on the basis of their soluble solids and total polyphenol contents, as well as on their antioxidant activities.
In addition to verbascoside, another compound with the same parent and fragment ions as verbascoside was present in the infusion. A 100 ml infusion of L. multiflora had significantly (P < 0.05) higher soluble solids and total polyphenol contents, and antioxidant activities than those of rooibos and honeybush. The rooibos infusion showed significantly (P < 0.05) higher soluble solids and total polyphenol contents as well as antioxidant activities than honeybush. On the basis of soluble solids, rooibos showed a significantly (P < 0.05) higher total polyphenol content and a lower ferric-reducing activity than L. multiflora. Both teas, however, did not differ significantly with respect to the DPPH antioxidant activity.
The effect of steam pasteurisation on the microbial load of L. multiflora herbal tea leaves was evaluated. Five samples of the tea were steam pasteurised at 99.8°C for 2.5 min and five samples were unpasteurised. Microbial enumeration was conducted in duplicate on potato dextrose agar (PDA), plate count agar (PCA), violet red bile agar (VRBA), yeast peptone dextrose agar (YPDA), and de Man Rogosa Sharpe agar (MRS). Morphologically distinct colonies were isolated, sub-cultured and their Gram reaction recorded. These bacteria were identified to the species level using 16S ribosomal DNA (rDNA) sequence data.
Most of the bacteria identified belonged to the genus Bacillus. One species each from the genera Pantoea and Kocuria were also identified, but only the Bacillus species survived the steam treatment. Coliform bacteria detected prior to pasteurisation were not detected after steam treatment. Steam pasteurisation reduced the microbial load from 104 to 102 cfu.g-1. The effects of the steam pasteurisation on the soluble solid, total polyphenol, and the active compound contents of L. multiflora, as well as the antioxidant activities were studied. Pasteurisation did not significantly (P > 0.05) change the soluble solids, total polyphenol and active compound contents, or the antioxidant activity.
Steam pasteurisation is potentially an effective method to treat L. multiflora herbal teas prior to consumption. However, the steam treatment should complement good agricultural and hygienic practices rather than replace them as some bacteria can survive this treatment. The identification and quantification of verbascoside in L. multiflora infusion, as well as the relatively higher antioxidant contents compared to rooibos and honeybush should provide the basis for future studies on the therapeutic application of this herbal tea. Also, verbascoside could potentially form the basis for future quality control of L. multiflora. / AFRIKAANSE OPSOMMING: Daar is 'n wêreldwye toename in die verbruik van kruietee. Kruietee wat egter nie vooraf-behandelings ontvang om die mikrobiese lading te verlaag nie kan, ten spyte van moontlike gesondheidsvoordele, ook 'n potensiële gesondheidsrisiko vir verbruikers inhou. Die doel van hierdie studie was om 'n stoompasteurisasie-behandeling te ontwikkel wat die mikrobiese lading op Lippia multiflora teeblare, 'n kruietee van Ghana, te verlaag. Verder is die teenwoordige bakterieë geïdentifiseer en die effek van 'n stoombehandeling op die bio-aktiewe komponente in die teeblare is ook geëvalueer.
'n Hoë-druk vloeistof-chromatografie metode is ontwikkel en ge-optimiseer vir die identifikasie en kwantifisering van verbaskosied, 'n hoof antioksidant komponent in L. multiflora kruie aftreksels. Vloeistof chromatografie, gekoppel aan in-lyn massa spektroskopie is ook gebruik om die teenwoordigheid van die komponent in die aftreksel te bevestig. Tydens die kwantifiseringsproses is askorbiensuur as 'n stabiliseringsagent gebruik om die degradasie van verbaskosied te voorkom. Die warm water aftreksel van L. multiflora is vergelyk met die van Aspalathus linearis (rooibos) en Cyclopia spp. (heuningbos) in terme van hul opgeloste vastestof- en totale polifenol inhoude, asook hul antioksidant aktiwiteite.
'n Ander komponent buiten verbaskosied, maar met dieselfde ouer en fragment ione, was ook in die aftreksel teenwoordig. 'n 100 ml L. multiflora aftreksel het beduidend (P < 0.05) meer opgeloste vastestowwe, totale polifenole en antioksidant aktiwiteit getoon as rooibos en heuningbos. Rooibos het weer beduidend (P < 0.05) meer opgeloste vastestowwe, totale polifenole, en antioksidant aktiwiteit as heuningbos. In terme van opgeloste vastestowwe het rooibos 'n beduidende (P < 0.05) hoër totale polifenol inhoud en laer ferriet-reduserende aktiwiteit as L. multiflora. Beide tee het egter nie beduidend verskil ten opsigte van hul antioksidant aktiwiteit nie.
Die effek van stoompasteurisasie op die mikrobiese lading van L. multiflora kruieteeblare is geëvalueer. Vyf teemonsters is gestoompasteuriseer by 99.8°C vir 2.5 min en 5 verdere monsters is nie gepasteuriseer nie. Mikrobe-tellings is in Mikrobe-tellings is in
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duplikaat op potato dextrose agar (PDA), plate count agar (PCA), violet red bile agar (VRBA), yeast peptone dextrose agar (YPDA), en de Man Rogosa Sharpe agar (MRS) gedoen. Morfologies onderskeibare kolonies is geïsoleer, her-gekweek en hul Gram status genotuleer. Hierdie bakterieë is daarna tot op spesie-vlak geïdentifiseer deur 16S ribosomale DNS (rDNS) volgorde bepalings.
Die meerderheid van die geïdentifiseerde bakterieë behoort tot die genus Bacillus en een spesie elk van die genera Pantoea en Kocuria is ook geïdentifiseer. Slegs Bacillus spesies het egter die stoompasteurisasie behandeling oorleef. Kolivorme bakterieë wat voor pasteurisasie waargeneem is was afwesig na die stoom behandeling. Stoompasteurisasie het ook die mikrobiese lading van 104 na 102 kve.g-1 verminder. Die effek van stoompasteurisasie op die opgeloste vastestowwe, totale polifenole en die aktiewe-komponent inhoud van L. multiflora, asook die antioksidant aktiwiteit is bestudeer. Pasteurisasie het die opgeloste vastestowwe, totale polifenole, aktiewe komponente en die antioksidant aktiwiteit nie-beduidend (P > 0.05) verander.
Stoompasteurisasie kan potensieël 'n effektiewe metode wees vir die behandeling van L. multiflora kruietee voor verbruik. Die stoombehandeling moet egter saam met goeie landbou- en higiëniese praktyke gebruik word eerder as om dit te vervang aangesien sommige bakterieë hierdie stoombehandeling kan oorleef. Die identifikasie en kwantifisering van verbaskosied in L. multiflora aftreksels, asook die hoër antioksidant inhoud vergeleke met rooibos en heuningbos verskaf moontlikhede vir verder navorsing in die terapeutiese aanwending van hierdie kruietee. Verbaskosied kan ook moontlik die basis vorm vir toekomstige kwaliteitskontrole van L. multiflora.
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Development of sensory tools for quality grading of Cyclopia genistoides, C. longifolia, C. maculata and C. subternata herbal teasErasmus, Lene Mari 04 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The sensory profiles and the phenolic composition of C. genistoides, C. longifolia, C. maculata and
C. subternata, used for commercial production of honeybush tea, were determined with the aim to
develop quality control tools, such as sensory wheels and statistical models to predict the basic
taste and mouthfeel modalities using compositional data. Optimum fermentation parameters for C.
longifolia in terms of aroma and flavour development were determined by investigating eight
temperature/time regimes (80°C and 90°C for 8, 16, 24 and 32 h), using descriptive sensory
analysis (DSA). Fermentation at 80°C/24 h or 90°C/24 h significantly reduced the negative
sensory attributes present and produced a tea of good sensory quality. Previously, 80°C/24 h and
90°/16 h were shown to deliver optimum quality for the other three Cyclopia species.
A large sample set (N = 150) consisting of C. genistoides, C. maculata and C. subternata,
harvested during three production years (2010, 2012 and 2013), as well as C. longifolia harvested
in 2013, was used to develop sensory wheels. All the samples were produced by fermentation at
the two optimum fermentation temperature/time regimes of each species. The plant material was
sourced from different production regions and plantations to ensure inherent plant variation was
accommodated. The “characteristic” and generic sensory profile of honeybush was defined as a
“fynbos-floral”, “woody”, “fynbos-sweet” aroma and flavour, with a sweet taste and slightly
astringent mouthfeel. Species-specific sensory profiles were also identified. Cyclopia genistoides
had a strong “rose geranium” flavour and a perceptible bitter taste, whereas C. longifolia had a
similar sensory profile to that of C. genistoides, however, C. longifolia’s “rose geranium” flavour
was less prominent and its bitter taste not perceptible. Cyclopia maculata and C. subternata were
both described as having “caramel” and other “sweet-associated” notes and a slightly astringent
mouthfeel. These results were used to develop a generic sensory wheel for both aroma and
flavour, as well as similar wheels for each of the four Cyclopia species. Each sensory wheel
reflects the relative intensity of the sensory attributes, while prevalence of the major attributes were
accommodated in accompanying bar graphs.
Sorting was investigated as a rapid profiling technique to serve as an alternative to the
standard profiling method, descriptive sensory analysis (DSA). Instructed sorting was identified as
a possible rapid sensory profiling tool for the honeybush industry, especially when samples need to
be classified according to a selected list of sensory attributes. Uninstructed sorting can be used
when the aim is to categorise a group of samples freely according to similarities and thus
determine the natural grouping of samples within a broader sample set. The phenolic content of the respective four Cyclopia species differed qualitatively and
quantitatively. Of the compounds quantified only four compounds were present in all four species,
i.e. hesperidin, vicenin-2, mangiferin and isomangiferin. A larger number of compounds were
present in three out of four species. The predictive value of the phenolic compounds towards the
intensity of the taste and mouthfeel attributes (sweet, sour, bitter and astringent) was investigated using Pearson‟s correlation analysis, partial least squares regression (PLS) and step-wise
regression analysis. Potential “candidate predictors” for taste and mouthfeel attributes were
identified such as the xanthones, mangiferin and isomangiferin, being responsible for bitter taste
and astringency. / AFRIKAANSE OPSOMMING: Die sensoriese profiel en fenoliese samestelling van C. genistoides, C. longifolia, C. maculata en
C. subternata, waarvan heuningbostee geproduseer word, is bepaal om gehaltebeheer
hulpmiddels te ontwikkel soos sensoriese wiele en statistiese modelle wat die fenoliese
samestelling kan gebruik om die basiese smaak en mondgevoel eienskappe van infusies te
voorspel. Die optimum fermentasie parameters vir C. longifolia in terma van aroma- en
geurontwikkeling is bepaal deur agt temperatuur/tyd kombinasies (80°C en 90°C vir 8, 16, 24 en
32 h) te ondersoek met behulp van beskrywende sensoriese analise (BSA). Fermentasie by
80°C/24 h of 90°C/24 h het „n beduidende afname in die negatiewe sensoriese eienskappe
veroorsaak en tot die ontwikkeling van tee met ʼn goeie sensoriese kwaliteit gelei. Die fermentasie
parameters, 80°C/24 h en 90°/16 h, is voorheen aangedui as die optimale kondisies vir die
ontwikkeling van „n goeie kwaliteit tee vir die ander drie Cyclopia spesies.
'n Groot stel monsters (N = 150), bestaande uit C. genistoides, C. maculata en C.
subternata en ge-oes gedurende drie produksiejare (2010, 2012 en 2013), sowel as C. longifolia
ge-oes in 2013, is gebruik om die sensoriese wiele te ontwikkel. Die twee optimum fermentasie
temperatuur/tyd kombinasies van elke spesie is gebruik om die monsters te produseer.
Plantmateriaal afkomstig van verskillende produksiegebiede en plantasies is versamel ten einde te
verseker dat die monsters „n betekenisvolle hoeveelheid inherente variasie dek. Die generiese en
"karakteristieke" sensoriese profiel wat met heuningbos geassosieer word, is gedefinieer as 'n
"fynbos-blomagtige", "houtagtige", "fynbos-soet" aroma en geur, met 'n soet smaak en effense
vrank mondgevoel. Spesies-spesifieke sensoriese profiele is ook geïdentifiseer. Cyclopia
genistoides het 'n sterk "roos malva" geur en „n merkbare bitter smaak. Die sensoriese profiel van
C. longifolia is soortgelyk aan dié van C. genistoides, maar sy "roos malva" geur was minder
prominent en 'n bitter smaak was nie sensories waarneembaar nie. Beide C. maculata en C.
subternata het waarneembare "karamel" en ander "soet-verwante" eienskappe, asook 'n effense
vrank mondgevoel getoon. Die volle stel data is uiteindelik gebruik om 'n generiese sensoriese
wiel vir heuningbostee, asook spesies-spesifieke sensoriese wiele vir elk van die vier Cyclopia
spesies saam te stel. Die onderskeie sensoriese wiele weerspieël die relatiewe intensiteit van elk
van die sensoriese eienskappe, terwyl die voorkoms-frekwensie van die onderskeie sensoriese
eienskappe in gepaardgaande kolomgrafieke geillustreer is. Sortering, 'n vinnige profileringsmetode, is as alternatief tot die standaard
profileringsmetode, beskrywende sensoriese analise (BSA), ondersoek. Gestrukteerde sortering is
geïdentifiseer as 'n moontlike hulpmiddel vir die heuningbosbedryf om die sensoriese profiel van
heuningbos te bepaal, veral wanneer „n groot aantal monsters vinning geklassifiseer moet word
volgens 'n lys geselekteerde sensoriese eienskappe. Ongestrukteerde sortering kan gebruik word
wanneer die doel is om „n groot aantal monsters vrylik te kategoriseer volgens hul sensoriese
ooreenkomste of verskille.
Die fenoliese saamestelling van die vier Cyclopia spesies het kwalitatief en kwantitatief
verskil. Slegs vier van die gekwantifiseerde verbindings was teenwoordig in al vier spesies,
naamlik hesperidien, visenien-2, mangiferien en isomangiferien. Meer verbindings was egter
teenwoordig in drie van die vier spesies. Die voorspellingswaarde van die fenoliese verbindings tot
die intensiteit van die smaak en mondgevoel eienskappe (soet, suur, bitter en vrank) is ondersoek
met behulp van Pearson se korrelasie, gedeeltelike kleinste-kwadrate regressie (PLS) en stapsgewyse
regressie analises. Potensiële "kandidaat voorspellers" vir die smaak en mondgevoel
eienskappe, soos die xantone, mangiferien en isomangiferien, verantwoordelik vir 'n bitter smaak
en vrank mondgevoel, is geïdentifiseer.
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Effect of fluid substitutions on the total antioxidant capacity of breads :comparing the indigenous herbal teas rooibos and honeybush with black teaSeptoe, Nina Lee January 2011 (has links)
Thesis (MTech (Consumer Science: Food and Nutrition))--Cape Peninsula University of Technology, 2011.Includes bibliographical references (leaves 139-156). / Oxidative stress has been implicated in the development of a number of chronic
degenerative diseases. These diseases can often be prevented by dietary and
lifestyle changes. One major dietary aspect is increasing the intake of plant
foods, such as fruit and vegetables as they are rich in the major nutrient and nonnutrient
antioxidants. The South African population does not have an adequate
intake of fruit and vegetables and many barriers have been noted against
increasing the intake of these foods. Other avenues should therefore be sought
to increase the antioxidant intake. One such avenue is to use a basic food item
consumed often as an antioxidant carrier to increase the antioxidant intake.
Much interest has developed in functional foods and their therapeutic effects as
well as the use of nutraceuticals in food product development and food
fortification. Tea and its polyphenols, due to the antioxidant properties, is a
potentially viable option for nutraceutical and functional food use. Rooibos and
honeybush herbal teas, native to South Africa, can be potential nutraceutical
sources to increase antioxidant levels of food due to their unique polyphenol
content.
The objective of the study was to increase the total antioxidant capacity (TAC) of
a basic food item consumed regularly by most South Africans, such as brown
bread through fluid manipulation using rooibos, honeybush and black teas
respectively, as the replacement fluid for water in a standardised bread recipe
formulation. The TAC of these experimental breads were compared to the TAC
of the bread produced with no fluid manipulation (control bread) and a
commercially processed bread (reference bread). The experimental breads were
prepared using 2% weight per volume (w/v) and 5% (w/v) concentration levels for
rooibos, honeybush and black tea respectively. To ascertain the TAC of the
experimental breads, the fluorescein(FL)-based oxygen radical absorbance
capacity (ORACFL) method was used. The hydrophilic (H)-ORACFL assay was
used as the teas contain polyphenols which favour a water environment. The
results indicated that the H-ORACFL of the control bread using water as the fluid
and the commercial reference bread was significantly different (p < 0.05 for each)
to all the experimental bread formulations besides for the 2% (w/v) honeybush
experimental bread formulation. The 2% (w/v) honeybush experimental bread
formulation was therefore not considered for the consumer acceptance testing.
There was no significant difference (p > 0.05) in the H-ORACFL of the 2% (w/v)
rooibos and black tea experimental bread formulations, but the H-ORACFL of the
5% (w/v) black tea experimental bread formulation was significantly (p < 0.05)
higher than that of the 5% (w/v) rooibos experimental bread formulation. This
particular experimental bread formulation had a “golden-orange” colour with a
pungent smell due to the increase in rooibos concentration. The 5% (w/v) black
tea experimental bread formulation, however, had noted negative sensory
attributes of being densely textured with a very dark colour and a pungent and
overpowering taste of black tea. These sensory attributes and TAC results lead
to the rooibos experimental breads containing 5% (w/v) (as bread A) and 2%
(w/v) (as bread B) chosen for the consumer acceptance testing and rooibos
being a proudly South African product.
The participants (n = 85) of the consumer acceptance testing participated
voluntarily and were regular bread consumers. The sample was mostly female
(57.6%), in the age group of 18 to 24 years (54.1%), with an education level of
between three to four years post-matric/-grade 12 (71.7%) and single, living on
their own without children (76.4%). They also represented a sample which had
characteristics of a healthy lifestyle. Most participants perceived themselves as
being of an optimal body weight (55.2%) and the majority was non-smokers
(74.1%), physically active (63.5%), having no family history of chronic disease
(69.4%) and not consuming dietary supplements (70.5%).
Three sensory attributes of the experimental breads were rated for the
acceptance testing and included appearance/colour, flavour/taste and
texture/mouthfeel. Both the experimental bread formulations was accepted
favourably regarding the above-mentioned sensory attributes. The three liking
acceptance categories, ‘neither like nor dislike’ (neutral response), ‘like’ and ‘like
very much’ were the most commonly indicated by the participants which also
resulted in the experimental breads being rated as fair, good and very good
according to the development scores. Although both breads were very similarly
scored, there was a trend for bread A to be rated slightly higher regarding the
above-mentioned sensory attributes. The acceptance category, ‘like’/good was
scored the highest for bread A according to the sensory attributes of
appearance/colour (56.5%), flavour/taste (55.3%) and texture/mouthfeel (50.6%).
There was no significant association/difference (p > 0.05 for each) between the
participants’ demographic characteristics and their overall acceptance of the
experimental breads. Most of the participant biographic characteristics also had
no significant (p > 0.05 for each) impact on the sensory attribute acceptance of
the experimental breads. Although the majority (75%) of the participants
consumed rooibos, there was no significant (p > 0.05) association/difference
between the participants’ tea consumption and their acceptance of the
experimental breads. Although most participants (64%) had no awareness of
functional foods, most indicated willingness to purchase foods with added health
benefits (93%) and to pay more for foods with added health benefits (73%).
These results indicated a general acceptance of bread with functional food
characteristics and the possibility of purchasing such products with added health
benefits and even at a higher price premium.
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Response of fever tea (Lippia Javanica) to fertigation frequency, growth medium and propagation methodMpati, Kwena Winnie. January 2005 (has links)
Thesis (M. Sc.(Agric))(Horticulture)-University of Pretoria, 2005. / Includes bibliographical references. Available on the Internet via the World Wide Web.
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從文化創意角度探討澳門涼茶產業的發展策略 / Study on development strategies of herbal tea industry in Macao from the perspective of cultural creativity林少芳 January 2017 (has links)
University of Macau / Institute of Chinese Medical Sciences
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Effects of micronutrients on growth and quality of bush tea (Athrixia phylicoides DC)Maedza, Khathutshelo Vuwani 20 April 2016 (has links)
Bush tea (Athrixia phylicoides DC.) is a herbal beverage and medicinal plant indigenous to South Africa. A trial was conducted to determine the effect of micronutrients on the plant growth and quality of bush tea. The trial was laid out in a completely randomized block design with five replicates. Treatments consisted of single applications of Zinc (Zn), Copper (Cu), Boron (Bo), Iron (Fe) and Magnesium (Mg) at three levels (50ml/l, 100ml/l and 150ml/l) and a combination of all micronutrients. A control treatment with no spray was also included. Leaf analysis was conducted using Varian Liberty series II instrument. Total polyphenols were determined using the Folin Ciocalteau method and tannins were determined using Vanillin HCl method. Bush tea samples (one leaf per sample) were analysed using head space solid phase micro-extraction gas chromatography (HS-SPME-GC-MS).
Results of this study demonstrated that application of micronutrients increased the total polyphenols, tannins and total flavonoids in bush tea, with most of the increase in total polyphenols (77.5-93.7 mg/g) occurring in combination B + Zn + Fe + Cu + Mg treatment, increase in tannins (87.3-99.5 mg/g) occurring in copper treatment and increase in total flavonoids (164.6-176.6 mg/g) occurring in mixture (B + Zn + Fe + Cu + Mg) treatment.
Results also show a significant increase in the quality and plant growth of bush tea. Five major compounds were identified (>80% identification probability) namely alpha-pinene, beta-pinene, myrcene, beta-caryophyllene and caryophyllene oxide. Linear relationship between percentage leaf tissues and treatments levels of micronutrients in bush tea was also observed. Boron and copper treatments showed strong linear correlation with a positive relationship between treatments levels and leaf percentage. Therefore, for improved total polyphenols content in bush tea leaves, a combination of (B + Zn + Fe + Cu + Mg) is recommended. Tannin content in bush tea leaves were significantly increased at Cu50 ml/l, Cu100 ml/l and Cu150 ml/l. For improved total flavonoids content in bush tea leaves, a combination of foliar spray of (B + Zn + Fe + Cu + Mg) is recommended. The LC-MS observations from the study showed no significant qualitative difference between control and micronutrient treatments with these treatments showing similar number of peaks. There was a significant quantitative difference between control and where magnesium peaks applied at adequate rates at (50 ml/l and 100 ml/l) and combination of (B + Zn + Fe + Cu + Mg) applied at (10 ml/l and 20 ml/l) / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
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Development of in vitro models to investigate the anti-inflammatory properties of Cyclopia Maculata and other South African herbal teas : a comparative studyKeet, Lana 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Chronic inflammation is suggested to contribute to cancer development and
therefore a potential target for chemoprevention. In the skin, keratinocytes and
macrophages play an integral part in acute and chronic inflammation, with
interleukin 1-α (IL-1α) and tumor necrosis factor α (TNF-α) as key cytokines
governing this process. Green tea (Camellia sinensis) and the South African herbal
teas, rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.) displayed antiinflammatory
effects in mouse and human skin. To further investigate the antiinflammatory
properties of green tea and the herbal teas, rooibos and honeybush (C.
subternata and C. maculata) herbal teas, suitable cell culture models were
developed and validated utilising human keratinocytes (HaCaT) and monocyte (THP-
1) derived macrophages. Aqueous extracts of the green tea and unfermented herbal
teas were prepared and their chemical composition determined by high performance
liquid chromatography (HPLC) and the antioxidant activity characterised utilising
different antioxidant assays. Green tea and rooibos exhibited similar antioxidant
activities while C. maculata displayed the lowest overall antioxidant activity of all the
extracts, despite possessing the highest mangiferin level, the major polyphenol in
honeybush. The modulation of cytokine release was studied in (i) an UVB-induced
pre-exposure HaCaT model monitoring the accumulation of IL-1α and (ii) a LPS
stimulated THP-1 macrophage model monitoring the TNF-α release, utilising both a
pre-exposure and co-exposure extract regimens. In the pre-exposure HaCaT
inflammatory model the UVB-induced IL-1α was decreased by the green tea extract
while a far weaker response was obtained with the rooibos extract. Both the
honeybush extracts displayed a significant effect in the reduction of IL-1α with C.
subternata exhibiting a slight increased protection at a lower extract concentration. In
the pre-exposure THP-1 derived macrophage model, green tea and the herbal tea
extracts inhibited TNF-α release in a dose dependent manner in the absence of an
overt loss in cell viability and apoptosis at lower extract concentrations, suggesting a
typical anti-inflammatory effect. In the co-exposure model, the different extracts also
exhibited an anti-inflammatory effect at the lowest concentrations in the absence of
apoptosis while at higher extract concentrations the effect was masked by a
decrease in cell viability and increased apoptosis. C. maculata exhibit differential effects when considering the inhibition of cytokine production and, depending on the
cell model, either exhibited a weaker or stronger effect when compared to C.
subternata and rooibos. Phenolic diversity of the different teas is likely to explain the
differential effects in the antioxidant assays and cell culture models with respect to
the regulation of the production of the inflammatory markers. Proposed mechanism
for the anti-inflammatory effects include the modulation of oxidative stress via
various pathways and the subsequent down regulation of nuclear factor kappa β
(NFκB) and activated protein-1 (AP-1) which are key regulators of cytokine
production governing the inflammatory response. / AFRIKAANSE OPSOMMING: Kroniese inflammasie van die vel kan bydra tot die ontwikkeling van kanker en is dus
’n potensiële area om te teiken in die voorkoming van velkanker. Keratinosiete en
makrofage speel ’n integrale rol in akute en chroniese inflammasie van die vel en
TNF-α en IL-1α is die belangrikste sitokiene wat hierdie proses inisieer. Dit is bekend
dat ekstrakte van groen tee (Camellia sinensis) en die Suid-Afrikaanse kruietees,
rooibos (Aspalathus linearis) en heuningbos (Cyclopia spp.) ‘n anti-inflammatoriese
effek op die vel van muise en mense het. Om die anti-inflammatoriese aktiwitieit van
groen tee, rooibos en 2 heuningbos kruietees (C. subternata en C. maculata) verder
te ondersoek en te definieer is geskikte selkultuurmodelle ontwikkel en gevalideer
deur gebruik te maak van menslike keratinosiete (HaCaT) en monosiet (THP-1)
afgeleide makrofage. Water ekstrakte van groen tee en ongefermenteerde kruietees
is voorberei en die chemiese samestelling deur hoë druk vloeistof chromatografie
(HDLC) bepaal. ‘n Verskeidenheid van antioksidant bepalingstoetse is gebruik om
die antioksidant aktiwiteit van die ekstrakte te meet. Groen tee en rooibos het
soortgelyke antioksidant aktiwiteite getoon, terwyl C. maculata die swakste algehele
aktiwiteit getooon het, ten spyte van die teenwoordigheid van hoёr vlakke van
mangiferin, die belangrikste polifenoliese verbinding in heuningbos. Modulasie van
sitokiene is verder bestudeer in (i) ’n UVB-geïnduseerde vooraf-blootstelling HaCaT
model, waartydens akkumulering van IL-1α gemonitor is en (ii) ‘n lipopolisakkaried
(LPS)-gestimuleerde THP-1 makrofaag model, waar die vrystelling van TNF-α
gemonitor is. Vir die THP-1 model is beide die voor en gelyktydige blootstelling
benaderings vir die ekstrakte met LPS gebruik. In die keratinosiet model, waar die
selle aan ekstrakte blootgestel is voor UVB bestraing, is IL-1α beduidend verlaag
deur die groen tee ekstrak, terwyl ’n swakker reaksie gesien is met rooibos. Beide
heuningbos ekstrakte het ’n beduidende invloed in die vermindering van IL-1α
getoon, waar C. subternata ’n effense verhoogde beskerming teen selsterfte by ‘n
laer ekstrakkonsentrasie toon. Blootstelling van die makrofage aan al vier ekstrakte
voor LPS stimulasie (vooraf-blootstelling), het gelei tot inhibisie van TNF-α vrystelling
op ’n dosis afhanklike wyse en die afwesigheid van apoptose en selsterftes by lae
ekstrak konsentrasievlakke. Hierdie waarnemings dui op ’n tipiese antiinflammatoriese
effek. In die gelyktydige-blootstelling model verlaag al die ekstrakte TNF-α vrystelling teen die laagste ekstrak konsentrasievlakke, in die afwesigheid van
apoptose en met geen effek op seldood nie. Hoёr ekstrak konsentrasievlakke het
sitotoksisiteit en verhoogde apoptose getoon, dus was die anti-inflammatoriese effek
gemaskeer. C. maculata toon ‘n variërende effek met betrekking tot antioksidant
aktiwiteit en die bekamping van sitokien produksie, afhangend van die model wat
bestudeer is. Die verskeidenheid fenoliese verbindings teenwoordig in die
verskillende tee ekstrakte is waarskynlik die rede vir die effekte wat waargeneem is
tydens antioksidant toetsing en selkultuurmodelle. Die anti-inflammatoriese
meganismes wat deur hierdie studie voorgestel word sluit die modulasie van
oksidatiewe stres via verskeie metaboliese paaie in. Modulasie van oksidatiewe
stres lei tot af-regulering van kernfaktor-kappaB (NF-κB) en aktiveerderproteïen-
1(AP-1), wat sleutel reguleerders van sitokien produksie tydens inflammatoriese
respons is.
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