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Anaerobic digestion at mesophilic and thermophilic temperature : with emphasis on degradation of phenols and structures of microbial communities /Levén, Lotta, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2006. / Härtill 3 uppsatser.
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Association of organic compounds to dissolved and particulate natural organic matter in soils /Frankki, Sofia, January 2006 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2006. / Härtill 4 uppsatser.
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Sensory and phenolic profiling of Cyclopia species (Honeybush) and optimisation of the fermentation conditionsTheron, 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.
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Phenolic composition and in vitro antioxidant capacity of South African plums (Prunus salicina Lindl.)Venter, Alet 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Phenolic compounds of the types present in plums have been found to exhibit health-promoting properties associated with their antioxidant capacity. Fruits with red peel and/or flesh are thus sought-after for their high antioxidant levels. In the current study South African plum (Prunus salicina Lindl.) cultivars and selections, harvested during two consecutive fruit seasons, were compared in terms of general fruit attributes (colour, firmness, °Brix, pH, titratable acidity), phenolic composition and antioxidant capacity. The effect of season and a commercial cold storage and ripening regime was also investigated.
A reversed-phase high-performance liquid chromatography-diode-array-fluorescence detection (HPLC-DAD-FLD) method suitable for use with mass spectrometry (MS) detection, was optimised for separation and identification of phenolic compounds from four phenolic groups (phenolic acids, anthocyanins, flavan-3-ols and flavonols) in six South African plum cultivars and five selections. Parameters that were optimised include the mobile phases, analysis temperature and gradient program. Good stability, linearity and inter- and intra-day precision were obtained. Identification of compounds was based on comparison of retention times, UV-Vis spectra and mass fragments with available authentic phenolic standards and/or literature data. The optimised method allowed identification or tentative identification of twenty-four phenolic compounds, including cyanidin-3-O-glycosides, quercetin glycosides, monomeric, dimeric and trimeric flavan-3-ols, and hydroxycinnamic acids. An on-line ABTS•+ (2,2ʹ-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid)) antioxidant assay, performed for qualitative evaluation of the antioxidant response of individual phenolic compounds, indicated the flavan-3-ols as major antioxidants in plums.
Eighteen phenolic compounds were quantified, including anthocyanins and flavonol glycosides, flavan-3-ols (monomers and dimers) and hydroxycinnamic acids. Phenolic composition differed greatly between cultivars and selections. Cyanidin-3-O-glucoside was the predominant anthocyanin in plums with red peel and/or flesh, followed by cyanidin-3-O-rutinoside. Cyanidin-3-O-galactoside was present only in the cultivar Laetitia (red peel, yellow flesh). The ripe fruit of Ruby Red and PR04-19, both with red peel and flesh, had the highest anthocyanin content for the first and second harvest season, respectively. Neochlorogenic acid and quercetin-3-O-glucoside were the major phenolic acid and flavonol, respectively. Chlorogenic acid, 3-O-p-coumaroylquinic acid and several quercetin-glycosides and -diglycosides were also present in some cultivars and selections. Procyanidin B1 was the flavan-3-ol present in the highest concentration in the majority of cultivars and selections and its content correlated with the (+)-catechin content, while the same was observed for procyanidin B2 and (-)-epicatechin.
The effect of cold storage and ripening on fruit attributes differed greatly between cultivars and selections. The increase and decrease in pH and titratable acidity, respectively, were as expected for ripe fruit as opposed to unripe fruit. Ripe fruit had higher a*-values and lower L*-values. The cold storage and ripening regime had no significant effect on total polyphenol and total flavan-3-ol content of the cultivars and selections, but the anthocyanin content increased in some cases.
In terms of in vitro antioxidant capacity, the selections PR04-32 and PR04-35, both with red peel and flesh, had the highest antioxidant capacity, irrespective of assay. Sapphire (red peel, yellow flesh), with the lowest total polyphenol content, also had the lowest antioxidant capacity in the ORAC and FRAP assays. Both the total polyphenol and flavan-3-ol contents correlated significantly to antioxidant capacity, irrespective of assay. / AFRIKAANSE OPSOMMING: Fenoliese verbindings, soos teenwoordig in pruime, is bekend vir hul gesondheidsbevorderende eienskappe wat geassosieer word met antioksidant kapasiteit. Vrugte met ‘n rooi skil en/of vleis is veral gesog as gevolg van hul hoë antioksidant aktiwiteit. Met hierdie studie is Suid-Afrikaanse pruim (Prunus salicina Lindl.) kultivars en seleksies, geoes tydens twee opeenvolgende seisoene, vergelyk in terme van algemene vrug einskappe (kleur, fermheid, °Brix, pH en titreerbare suurheid), fenoliese samestelling en antioksidant kapasiteit. Die effek van ‘n kommersiële koelopberging en rypwording prosedure is ook ondersoek.
‘n Omgekeerde-fase hoë-druk vloeistof chromatografie (HPLC) metode met diode-opstelling en fluoressensie deteksie, maar wat ook geskik is vir massa spektrometrie (MS), is geoptimiseer om fenoliese verbindings te skei en te identifiseer in Suid-Afrikaanse pruime. Verbindings van vier fenoliese groepe (fenoliese sure, antosianiene, flavan-3-ole en flavonole) wat in ses kultivars en vyf seleksies voorgekom het, is ondersoek. Die vloeistof fases, skeidingstemperatuur en gradiënt van die metode is geoptimiseer. Goeie resultate vir stabiliteit, lineariteit en inter- en intra-dag akkuraatheid is verkry. Verbindings is geïdentifiseer deur vergelyking van retensie tye, UV-Vis spektra en massa fragmente met dié van egte fenoliese standaarde en/of met literatuur data. Vier-en-twintig fenoliese verbindings is geïdentifiseer of voorlopig geïdentifiseer, insluitende sianidien- en kwersetien glikosiede, flavan-3-ol monomere, dimere en trimere, en hidroksikaneelsure. ‘n Aanlyn ABTS•+ (2,2 ʹ-azino-di-(3-etielbensotialosien-sulfoon suur) radikaal katioon blussingstoets is gebruik om die antioksidant reaksie van individuele polifenole op ‘n kwalitatiewe wyse te evalueer en flavan-3-ole is as hoof antioksidante in pruime aangetoon. Kwantifisering van agtien verbindings, insluitende antosianiene, flavonol glikosiede, flavan-3-ole (monomere en dimere) en hidroksikaneelsure, was moontlik met hierdie geoptimiseerde metode. Die fenoliese samestelling het aansienlik verskil tussen kultivars en seleksies. Sianidien-3-O-glukosied was die hoof antosianien in pruime met ‘n rooi skil en/of vleis, gevolg deur sianidien-3-O-rutinosied. Sianidien-3-O-galaktosied het slegs in Laetitia (rooi skil en geel vleis) voorgekom. Ryp vrugte van Ruby Red en PR04-19, beide met rooi skil en vleis, het onderskeidelik die hoogste antosianieninhoud gehad met die eerste en tweede seisoen se oeste. Neochlorogeniese suur en kwersetien-3-O-glukosied was die hoof fenoliese suur en flavon-3-ol, onderskeidelik. Chlorogeniese suur, 3-O-p-kumarienkwiniensuur en verskeie kwersetien glikosiede en diglikosiede was teenwoordig in sekere kultivars/seleksies. Die flavan-3-ol, prosianidien B1, was teenwoordig in die hoogste konsentrasie in die meerderheid kultivars/seleksies. Die prosianidien B1 inhoud het met die (+)-katekien inhoud gekorreleer, terwyl dieselfde gevind is vir prosianidien B2 en (-)-epikatekien.
Die effek van koelopberging en rypwording op die algemene vrug einskappe het tussen kultivars en seleksies verskil. Die pH en titreerbare suurheid het onderskeidelik toegeneem en afgeneem, soos verwag is vir ryp vrugte teenoor onryp vrugte. Ryp vrugte het hoër a*-waardes en laer L*-waardes getoon. Koelopberging en rypwording het geen beduidende effek op die totale polifenol- en totale flavan-3-ol inhoud gehad nie, maar die antosianieninhoud het vir sommige kultivars en seleksies toegeneem.
In terme van in vitro antioksidant kapasiteit het die seleksies PR04-32 en PR04-35, beide met rooi skil en vleis, die hoogste antioksidant kapasiteit getoon, ongeag die antioksidant toets wat gebruik is. Sapphire (rooi skil en geel vleis) het die laagste totale polifenolinhoud gehad, asook die laagste antioksidant kapasiteit soos bepaal deur die ORAC en FRAP toetse. Beide die totale polifenol- en flavan-3-ol inhoud het beduidend met die antioksidant kapasiteit korreleer, ongeag van die toets wat gebruik is.
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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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Compostos fenólicos em uvas e vinhos da variedade Merlot / Phenolic compounds in Merlot grapes and winesFogaça, Aline de Oliveira 23 April 2012 (has links)
The main aim of this work was to evaluate the phenolic compounds of Merlot grapes and wines, from vineyards located at Dom Pedrito (Campanha Gaúcha) and Bento Gonçalves (Serra Gaúcha). The following aspects were evalueted: fenolic and industrial ripeness; correlation between the grapes phenolic potencial and the wine phenolics; changes in phenolic compounds during the aging of the wines; impacto of maceration time of wine phenolic composition. The study was conducted for three years: 2009, 2010 and 2011. After grape ripeness evaluations, grape samples were harvested, crushed and fermented , with three different maceration techniques. The phenolic composition of the wines were analyzed after bottling and during aging. The vineyard localization have a great influence on Merlot wine phenolic composition; the grape characteristics was most important than maceration techniques to the wine composition. Important differences, among this two regions, have been found in the content and in the composition of phenolic compounds in the grapes and wines. Dom Pedrito grapes achieved a good cellular maturity, however, when compared with Bento Gonçalves grapes, the anthocyanin content is lower and the quantity of seeds tannins are higher than 50%. The phenolic potential allowed to estimate the total phenolic content, color due polymeric anthocyanins and procyanidin content of Merlot wines. Extended maceration (15 days) are recommended to Dom Pedrito grapes, however it is observed an increase in the pH value; the total crushing of grapes or not will not influence this aspect. During the aging, the results are dependent of vineyard location; Dom Pedrito wines showed a greater polimerization velocity and the differences among maceration times decreased for all wines studied. The main differences among wines from this two regions were color intensity, anthocyanin content, color due polymeric anthocyanin and total phenolic conten of the wines. These facts allows to state that Merlot wines from Serra Gaúcha could be aging for a periodo greater than Campanha Gaúcha wines. / O objetivo principal deste trabalho foi realizar um estudo dos compostos fenólicos em uvas e vinhos da variedade tinta Vitis vinifera Merlot, cultivadas em vinhedos dos município de Dom Pedrito (região da Campanha Gaúcha) e de Bento Gonçalves (região da Serra Gaúcha). Para tanto os seguintes aspectos foram avaliados: maturação fenólica e industrial de uvas amostradas; correlação entre o potencial fenólico estimado nas uvas com a composição fenólica e a cor dos vinhos resultantes; mudanças nos teores de compostos fenólicos dos vinhos elaborados e efeito do tipo de maceração sobre os compostos fenólicos dos vinhos. O estudo foi realizado por três safras: 2009, 2010 e 2011. Após a análise da maturação fenólica e industrial, amostras destas uvas foram vinificadas em pequena escala, com diferentes técnicas de maceração. Os vinhos foram analisados após o engarrafamento e durante o envelhecimento em relação ao conteúdo de compostos fenólicos. As uvas e os vinhos da variedade tinta Merlot apresentaram diferenças de acordo com a localização do vinhedos, sendo que as características das uvas foram mais importantes para o vinho resultante do que as técnicas de vinificação empregadas. Foram encontradas diferenças importantes no conteúdo e no comportamento dos compostos fenólicos entre as duas regiões representadas nesse estudo, tanto em relação a uva quanto ao vinho. As uvas cultivadas nos vinhedos do município de Dom Pedrito atingem uma maturação celular adequada, no entanto, o teor de antocianinas é menor e o teor de taninos nas sementes é superior a 50%, comportamento oposto as uvas cultivadas no município de Bento Gonçalves. A análise do potencial fenólico das uvas permite estimar o conteúdo de polifenóis totais, a porcentagem da cor devido a antocianinas poliméricas e a quantidade de procianidinas presentes no vinho a ser elaborado com uvas dessa variedade. Em relação a técnica de vinificação para a região de Dom Pedrito, recomenda-se o uso de maceração extendida (15 dias no minímo), porém há uma tendência de elevação do valor de pH do vinho resultante; o esmagamento total ou não da uva não irá influenciar esse aspecto. Durante o envelhecimento, os vinhos apresentaram resultados de acordo com a região de origem da uva, sendo que os vinhos de Dom Pedrito apresentam uma maior velocidade de polimerização; as diferenças entre os tempos de maceração diminuem com o envelhecimento do vinho para todos os vinhos analisados nesse estudo. As principais diferenças entre os vinhos dos dois municípios estudados deve-se a intensidade de cor, ao conteúdo de antocianinas, a porcentagem de cor devido a antocianinas poliméricas e ao teor de polifenóis totais nos vinhos. Estes fatos permitem afirmar, em parte, que os vinhos Merlot da Serra Gaúcha podem ser envelhecidos por mais tempo e que os vinhos Merlot oriundos da Campanha Gaúcha podem e devem ser consumidos mais jovens.
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Synthèse de composés phénoliques de type diarylheptanoïde : évaluation de leurs propriétés antioxydantes et anti-inflammatoires / Synthesis of diarylheptanoïd phenolic compounds : evaluation of their antioxidant and anti-inflammatory propertiesMaurent, Kelly 10 November 2017 (has links)
L'athérosclérose est une des premières causes de mortalité dans les pays industrialisés. Elle est à l'origine de diverses pathologies telles que les infarctus du myocarde, les accidents vasculaires cérébraux et les maladies des artères coronaires. Deux facteurs clés sont à l'origine de l'athérosclérose : 1) un stress oxydant qui conduit à l'oxydation des lipoprotéines de basse densité dans la paroi artérielle et qui constitue la première étape du processus athérosclérotique ; 2) un processus inflammatoire auto-entretenu qui permet le développement des dernières étapes de l'athérogénèse conduisant à la formation d'une plaque d'athérome. La maladie reste silencieuse jusqu'à ce qu'elle se dévoile subitement à travers les évènements cités précédemment. L'utilisation d'antioxydants synthétiques ou naturels pour lutter contre l'athérogénèse est prouvée in vitro mais s'avère inefficace in vivo. Devant ce constat, une des stratégies envisagées consiste à inhiber conjointement le stress oxydant et l'inflammation. Dans ce but, des molécules présentant la double propriété, antioxydante et anti- inflammatoire, s'avèrent intéressantes. Les dérivés phénoliques d'origine naturelle sont connus pour leurs propriétés antioxydantes, principalement dues à leur caractère piégeur de radicaux libres grâce à la présence du noyau phénolique Dans le cadre de notre projet, nous nous sommes intéressés aux diarylheptanoïdes macrocycliques qui sont des composés phénoliques extraits de différentes plantes et très peu exploités malgré des propriétés biologiques intéressantes. Parmi eux, le tédarène A, macrocycle naturel de type cyclodécaphane, extrait en 2012 d'une éponge marine, la Tedania Ignis, présente des propriétés anti-inflammatoires et un caractère antioxydant. Au cours de ce travail de thèse, la première synthèse totale du tédarène A a été réalisée. Les étapes clés ont concerné l'introduction stéréocontrollée du système diènique (Z,E) non conjugué au noyau phénol et la cyclisation en conditions de Ullmann du macrocycle diarylheptanoïde. Différents analogues du tédarène A ont été également conçus et préparés. Les modifications structurelles ont été introduites au niveau de la chaîne heptanoïde des macrocycles synthétisés. Le tédarène A et les différents analogues de type diarylheptanoïdes linéaires et macrocycliques synthétisés ont été évalués pour leurs activités antioxydante et anti- inflammatoire. / Atherosclerosis is one of the first cause of mortality in industrialized countries. It leads to cerebrovascular accident, stroke and all of the coronary heart diseases. Two key steps induce atherosclerosis : 1) an oxidative stress leading to the low density lipoproteins oxidationand initiating atherogenesis ; 2) a self-sustained inflammatory process allowing the last steps development of atherogenesis giving the atheroma plaque formation. This pathology is silent until it appears suddenly with the consequences mentionned above. The synthetic or natural antioxidants use to fight atherosclerosis is effective in vitro but not in vivo. One the basis of these informations, one of the proposed strategies is to inhibit both oxidative stress and inflammation. Therefore, it will be interesting to design molecules with a dual activity : antioxidant and anti-inflammatory. Natural phenolic compounds are well-know for their antioxidant activities due to the phenol moiety wich is able to trap free radicals. As part of our project, we are interested in macrocyclic diaryl heptanoids wich are phenolic compounds extracted from different plants and under-exploited despite interesting biological properties. Among them, tedarene A, a natural macrocycle type cyclodecaphane, extracted in 2012 from a marine sponge, Tedania Ignis, exhibits anti-inflammatory and antioxidant property. During this Ph.D work, the fisrt total synthesis of tedarene A was carried out. The key steps involved the stereocontrolled introduction of the diene system (Z,E) not conjugated to the phenol moiety and the cyclization of the diarylheptanoid macrocycle using Ullmann conditions. Various analogs of tedarene A were also designed and prepared. Structural changes were introduced onto the heptanoid chain part of synthesized macrocycles. Tedarene A and the various synthesized linear and macrocyclic diarylheptanoid analogues were evaluated for their antioxidant and anti-inflammatory activities.
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Caracterização físico-química, teor de antioxidante e perfil sensorial de méis de abelhas submetidos à desumidificação e umidificação / Physicochemical characterization, antioxidant content and sensory profile of honey bee subjected to dehumidification and humidificationSilva, Mônica Cristina de Paiva 26 February 2015 (has links)
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Previous issue date: 2015-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The honey bee is a resulting food processing the nectar of plants by bees,
has its composition strongly influenced by the flowering, soil, climate conditions and bee
species. Thus, the honey bee Apis mellifera L. species and genus Melipona subnitida, with
different characteristics, both sensory and physical-chemical and antioxidants. The
Melipona subnitida honey stands out for high water content and therefore technological
processes (dehumidification and maturity) are performed to extend its useful life.
Otherwise, the humidifying Apis mellifera L. honey can result in a product similar in
characteristics to the Melipona honey, but with reduced caloric constituents. Thus, this
study aimed to evaluate the physic-chemical characteristics, antioxidant content and
sensory profile honeys of Apis mellifera L. and Melipona subnitida submitted
humidification and dehumidification treatments. For this, honey samples of Apis mellifera
L. and Melipona subnitida were collected in the Rio Grande do Norte state. Honeys packed
in sealed containers were transported to the Food Technology Laboratory of the
Universidade Federal Rural do Semi-Árido (UFERSA), located in the Center Campus in
the Mossoró-RN city, where they were stored by refrigeration (6 °C) until the completion
analyzes physicochemical (moisture, pH, free acidity, water activity, reducing sugars,
apparent sucrose, diastase activity, electrical conductivity, ash, hydroxymethylfurfural,
insoluble solids in water and color), antioxidant (phenolic compounds, flavonoids,
antioxidant capacity) and sensory profile (aroma, flavor, fluidity, color, acceptance and
purchase intent). For evaluation was used four samples of 1 L of honey for each bee
species. The samples were divided into two samples with equal quantities, was evaluated
in natura and the other was subjected to dehumidification in air circulating oven at 40 °C
and relative humidity 30 % (Melipona subnitida honey), and humidification by adding
distilled water (Apis mellifera L. honey). Data were subjected to analysis of variance (p
<0.01), the F test. For compare means, t tests were used (p <0.05) for the results of
physico-chemical analysis and antioxidants, and Friedman (p <0.05) for the results of the
sensory analysis. Treatment dehumidification honeys of Melipona subnitida significantly
changed the moisture content, water activity, reducing sugars, sucrose, ash, insoluble solids
and color. While the treatment of humidification honeys of Apis mellifera L. changed the
moisture content, water activity, reducing sugars, sucrose. As for the content (total
phenolics, flavonoids) and antioxidant capacity there were no treatment effects. However,
the sensory attributes of aroma, fluidity and color of honey show any differences in the
treatments. However, the flavor, acceptance and purchase intent were not affected by
honeys treatments of both species / O mel de abelha é um alimento resultante do processamento do néctar das
plantas pela abelha, tem sua composição bastante influenciada pela florada, solo, condições
climáticas e espécies de abelha. Assim, o mel de abelha da espécie Apis mellifera L. e do
gênero Melipona subnitida, possuem características distintas, tanto sensoriais quanto
físico-químicas e antioxidantes. O mel de Melipona subnitida destaca-se pelo elevado teor
de umidade e por isso, processos tecnológicos (desumidificação e maturação) são
realizados para prolongar a sua vida útil. De outra maneira, a umidificação do mel de Apis
mellifera L. pode resultar em um produto semelhante em características ao mel de
Melipona, mas com constituintes calóricos reduzidos. Diante disso, este trabalho teve por
objetivo avaliar as características físico-químicas, teor de antioxidante e perfil sensorial de
méis de Apis mellifera L. e Melipona subnitida submetidos a tratamentos de umidificação e
desumidificação. Para isto, foram coletadas amostras de mel de Apis mellifera L. e
Melipona subnitida, no estado do Rio Grande do Norte. Os méis acondicionados em
recipientes fechados foram transportados para o Laboratório de Tecnologia de Alimentos
da Universidade Federal Rural do Semi-Árido (UFERSA), localizado no Campus Central,
na cidade de Mossoró-RN, onde foram armazenadas sob refrigeração (6 ºC) até a
realização das análises físico-químicas (umidade, pH, acidez livre, atividade de água,
açúcares redutores, sacarose aparente, atividade diastásica, condutividade elétrica, cinzas,
hidroximetilfurfural, sólidos insolúveis em água e cor), antioxidante (fenólicos totais,
flavonóides, capacidade antioxidante) e perfil sensorial (aroma, sabor, fluidez, cor,
aceitação e intenção de compra). Para avaliação foram utilizadas quatro amostra de 1 L de
mel para cada espécie de abelha. As amostras foram divididas em duas sub-amostras com
quantidades iguais, uma foi avaliada in natura e a outra foi submetida à desumidificação
em estufa de circulação de ar a 40 ºC e UR de 30 % (mel de Melipona subnitida) e,
umidificação adicionando-se água destilada (mel de Apis mellifera L.). Os dados foram
submetidos à análise de variância (p<0,01), pelo teste F. Para a comparação de médias,
utilizaram-se os testes t (p<0,05) para os resultados das análises físico-químicas e
antioxidantes, e Friedman (p<0,05) para os resultados da análise sensorial. O tratamento de
desumidificação dos méis de Melipona subnitida alterou significativamente a umidade,
atividade de água, açúcares redutores, sacarose, cinzas, sólidos insolúveis e cor. Enquanto
o tratamento de umidificação dos méis de Apis mellifera L. alterou a umidade, atividade de
água, açúcares redutores e sacarose. Já para o teor (fenólicos totais, flavonóides) e
capacidade de antioxidante não se verificaram efeito de tratamento. Porém, os atributos
sensoriais de aroma, fluidez e cor dos méis apresentaram diferenças com os tratamentos.
Todavia, o sabor, aceitação e intenção de compra não foram influenciados pelos
tratamentos dos méis de ambas as espécies / 2017-09-08
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Soluções antioxidantes e tratamento térmico na qualidade de batata-doce minimamente processada / Antioxidant solutions and thermal treatment in the quality of sweet potato minimally processedCordeiro, Isabela Nogueira Fonseca 13 July 2018 (has links)
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Previous issue date: 2018-07-13 / Outra / A Batata-doce é um alimento versátil, de fácil aquisição e produção, entretanto, as raízes apresentam inconvenientes como desuniformidade, descasque e rápido escurecimento após o corte, por isso, esse vegetal mostra-se um produto com características a serem superadas pelo processamento mínimo. O uso de agentes antioxidantes e/ou tratamento térmico tem apresentado efeitos satisfatórios na qualidade pós-colheita de produtos hortícolas. Os ácidos cítrico e ascórbico atuam na inativação de enzimas responsáveis pelo escurecimento, devido à redução de pH e ação antioxidante, respectivamente. O tratamento térmico moderado que age na inativação de enzimas do escurecimento sem alterar a textura do vegetal. Nesse contexto, o objetivo desse estudo foi avaliar o efeito do ácido cítrico, ascórbico e tratamento térmico em diferentes concentrações e tempos na qualidade de batata-doce minimante processadas. As raízes de casca rosada e polpa amarela, foram, higienizadas, descascadas e feitos cortes transversais ao eixo principal obtendo rodelas de 1 cm de espessura, que foram submetidas a diferentes tratamentos, à saber, imersão em soluções de ácido citrico (AC) à 0, 1, 2 e 3% por 1 min; ácido ascórbico (AA) à 0, 1, 2 e 3% por 1min e tratamento térmico (TT) à 50°C por 0, 1, 3 e 5 min. Em seguida as batatas-doce foram centrifugadas e armazenadas em bandejas de tereftalado de polietileno (PET) a temperatura de 5 °C e 85% UR por um período de 8 dias. A cada 2 dias avaliou-se a perda acumulada de massa fresca, firmeza, índice de brancura, o pH, acidez titulável, sólidos solúveis, atividade respiratória. Amostras foram congeladas e armazenadas para análises posteriores de compostos fenólicos, atividade das enzimas peroxidase (POD), polifenoloxidase (PPO) e açucares solúveis. Batata-doce minimamente processada tratadas com 2% de ácido cítrico mostraram melhores resultados no escurecimento enzimático e qualidade do vegetal, enquanto o ácido ascórbico na concentração de 2%, apresentou melhor resultado na diminuição da atividade enzimática e qualidade do vegetal. O tratamento térmico a 50°C por 3 min, mostrou-se eficiente na qualidade de batata-doce minimamente processada. / Sweet potato is a versatile food, easy to acquire and produce, however, the roots present disadvantages such as unevenness, peeling and fast darkening after cutting, so this vegetable shows a product with characteristics to be overcome by the minimally processed. The use of antioxidants and / or heat treatment has shown satisfactory effects on the post-harvest quality of vegetables. The citric and ascorbic acids act in the inactivation of enzymes responsible for darkening, due to the reduction of pH and antioxidant action, respectively. The moderate heat treatment that acts in the inactivation of darkening enzymes without changing the texture of the vegetable. Therefore, this study aims to evaluate the effect of the acids citric and ascorbic combine with heat treatment at different concentrations and times in the quality of sweetened sweet potato processed. The roots with rosy peel and yellow pulp were cleaned, peeled and cut transversally around the principal axis, obtaining slices with 1 cm of thickness. The slices were submitted to different treatments, namely immersion in citric acid solutions (AC) at 0, 1, 2 and 3 % for 1 min; ascorbic acid (AA) at 0, 1, 2 and 3 % for 1min and, heat treatment (TT) at 50 °C for 0 (immersion in water at room temperature), 1, 3 and 5 min. Then, the pretreated sweet potatoes were centrifuged and stored in polyethylene terephthalate trays (pet) at 5°c and 85±5 % RH for a period of 8 days. Every 2 days the loss of accumulated fresh mass, firmness, whiteness index, pH titratable acidity, soluble solids and respiratory activity were evaluated. Samples were frozen and stored for further analysis of phenolic compounds, peroxidase enzyme activity (POD), polyphenoloxidase (PPO) and soluble sugars. The acid citric concentration of 2% provided the best whiteness index of the slices. Minimally processed sweet potato treated with 2% citric acid presented better results in enzymatic darkening and vegetable quality, while ascorbic acid at 2% concentration showed better results in the decrease of the enzymatic activity and the quality of the vegetable. The heat treatment at 50 °C for 3 min was efficient in the quality of the minimally processed sweet potato.
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Análise química, avaliação da atividade antioxidante e obtenção de culturas in vitro de espécies de hypericum nativas do Rio Grande do Sul / Chemical analysis, evaluation of the antioxidant activity and development of in vitro cultures of Hypericum species native of Rio Grande do SulBernardi, Ana Paula Machado January 2007 (has links)
Aproximadamente vinte espécies do gênero Hypericum (Guttiferae) têm ocorrência natural no Brasil, e concentram-se principalmente na região Sul do País. Considerando a importância deste gênero como fonte de substâncias com variadas atividades biológicas, tais como analgésica, antidepressiva, antimicrobiana, antiviral, antiproliferativa, entre outras, o presente trabalho teve como objetivos analisar a constituição química e o potencial antioxidante de espécies de Hypericum, desenvolver protocolos para manutenção de algumas espécies nativas através de culturas de tecidos e células e validar metodologia para quantificação de benzopiranos em H. polyanthemum proveniente de cultivo a campo, in vitro e aclimatizado. Utilizando-se métodos cromatográficos e espectroscópicos, foram isolados e identificados o ácido fenólico ácido 5-O-cafeoil-1-metoxi-quínico e os flavonóides 3,7-dimetil-quercetina, 3-Ometil- quercetina, I3,II8-biapigenina, guaijaverina, isoquercitrina e hiperosídeo, todos derivados da quercetina e obtidos da fração acetato de etila das partes aéreas de H. ternum. Ainda desta espécie, porém da fração n-hexano das raízes, obteve-se o derivado de floroglucinol uliginosina B. De H. myrianthum foram isolados e identificados os flavonóides quercetina e hiperosídeo, da fração metanólica das partes aéres, bem como os derivados de floroglucinol japonicina A e uliginosina B, fração n-hexano das raízes. Através do método colorimétrico de Folin-Ciocalteau, foram quantificados os teores de fenólicos totais das espécies H. caprifoliatum, H. carinatum, H. myrianthum e H. polyanthemum, verificando-se teores variando entre 37,40 a 228,36 mg EQ/g de extrato seco. Utilizando as técnicas de TRAP (Total Radical-trapping Antioxidant Parameter), ORAC-PGV (Oxygen Radical Absorbance Capacity) e reação bioautográfica e espectrofotométrica com radicais DPPH• (2,2 difenil-1-picril-hidrazil) evidenciou-se que extratos brutos metanólicos, e frações metanólicas e n-hexânicas das espécies H. caprifoliatum, H. carinatum H. myrianthum e H. polyanthemum, bem como produtos isolados de espécies de Hypericum nativas do Estado apresentam potencial antioxidante. A regeneração in vitro foi obtida em meio Murashige & Skoog modificado (MΔ) para as espécies H. campestre, H. caprifoliatum, H. carinatum, H. myrianthum, H. polyanthemum e H. ternum utilizando diferentes combinações e concentrações dos reguladores de crescimento 6-benzilamino-purina (BAP), ácido naftaleno-acético (ANA) e ácido 2,4 dicloro-fenóxi-acético (2,4-D). Plântulas dessas espécies foram posteriormente aclimatizadas com sucesso, sendo cultivadas a campo. As espécies micropropagadas demonstraram perfis químicos qualitativamente similares aos apresentados pelas plantas desenvolvidas no campo, de modo que o cultivo in vitro apresenta-se como uma alternativa interessante aos métodos convencionais de produção de biomassa para extração de metabólitos secundários bioativos. Culturas de calos foram estabelecidas em meio MΔ para H. myrianthum, H. polyanthemum e H. ternum, utilizando diferentes combinações e concentrações dos reguladores de crescimento cinetina (CIN), BAP, ANA e 2,4-D. Considerando-se as importantes atividades biológicas de produtos obtidos de H. polyanthemum foi estabelecida uma metodologia para quantificação, através da técnica de CLAE, de benzopiranos no extrato apolar desta planta, espécie de ocorrência restrita. A validação analítica foi avaliada conforme o preconizado por normas reconhecidas internacionalmente, com análise dos parâmetros linearidade, seletividade, precisão (repetibilidade e precisão intermediária), exatidão e limites de detecção e quantificação, demonstrando resultados coerentes com os exigidos pela legislação vigente. Foram evidenciadas variações no teor de benzopiranos na planta micropropagada, aclimatizada e desenvolvida a campo, provavelmente devido a fatores, que vão desde a regulação endógena de processos fisiológicos até variações sazonais no cultivo. / Approximately twenty species of Hypericum genus (Guttiferae) are native of Brazil, occurring mainly in the South region. Considering the importance of the genus as a source of compounds with different biological activities, such as analgesic, antidepressant, antimicrobial, antiviral, antiproliferative, among others, the objectives of this work were to evaluate the phytochemistry and antioxidant potential of some Hypericum species, to develop protocols for the maintenance of the species through in vitro cultures and to validate a technique to quantify the benzopyrans in H. polyanthemum grown in field, in vitro and acclimatized plants. Chromatographic and spectroscopic techniques were used for the isolation and identification of the phenolic acid 5-O-caffeoyl-1-methyl ester-quinic acid and the flavonoids quercetin 3,7-dimethyl ether, quercetin 3-methyl ether, I3,II8-biapigenin, guaijaverin, isoquercitrin and hyperoside, all of them quercetin derivatives and obtained from ethyl acetate fraction of H. ternum aerial parts. From n-hexane fraction of the roots of this species the phloroglucinol derivative uliginosin B was obtained. The flavonoids quercetin and hyperoside (from aerial parts of methanolic fraction), and the phloroglucinol derivatives japonicin A and uliginosin B (from n-hexane fraction of roots) were isolated from H. myrianthum. Total phenol concentration ranging from 37.40 to 228.36 mg QE/g dry extract (Folin–Ciocalteu colorimetric method) in H. caprifoliatum, H. carinatum, H. myrianthum and H. polyanthemum was measured. The antioxidant potential of the extracts obtained from H. caprifoliatum, H. carinatum, H. myrianthum and H. polyanthemum and isolated compounds was determined using TRAP (Total Radicaltrapping Antioxidant Parameter), ORAC-PGR (Oxygen Radical Absorbance Capacity) and bioautographic and spectrofotometric reaction with DPPH• (2,2-diphenyl-1- picrylhydrazyl radical techniques. In vitro regeneration of H. campestre, H. caprifoliatum, H. carinatum, H. myrianthum, H. polyanthemum and H. ternum was obtained in Murashige & Skoog modified medium (MΔ) supplemented with differents combinations and concentrations of the growth regulators 6-benzylaminopurine (BAP), α-naphthalene acetic acid (ANA) and 2,4-dichlorophenoxyacetic acid (2,4-D). Plantlets were acclimatizated and transferred to open field. The micropropagated species showed chemical pattern qualitatively similar to field grown plants, demonstrating that the in vitro cultures are an alternative to conventional methods for biomass production of bioactive secondary metabolites. Callus cultures of H. myrianthum, H. polyanthemum and H. ternum were established in MΔ medium using different combinations and concentrations of kinetin (CIN), BAP, ANA and 2,4-D. Considering the important biological activities of the benzopyrans isolated from H. polyanthemum, an HPLC quantification methodology was established. Analytical validation was performed according to international rules (linearity, selectivity, precision, accuracy, detection and quantitation limits) showing results coherent with those required by the current legislation. Variation of the benzopyrans concentration was observed among the micropropagated plantlet, acclimatizated and field grown plants, probably due to factors as endogenous regulation of physiological process and seasonal variation of the culture.
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