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Structural and synthetic studies of sesquiterpenoids and flavonoids isolated from Helichrysum speciesJanuary 2008 (has links)
The genus Helichrysum (Asteraceae) consists of approximately 500 species worldwide,
with 245 indigenous to South Africa. As a result of the large number of species, the
chemistry and biological activity of several species have not yet been investigated. The aim
of this project was to investigate the phytochemistry of three species and propose a
synthetic route to one of the antibacterial compounds isolated.
An extensive literature review regarding the widespread traditional uses, biological activity
and phytochemistry of the South African Helichrysum species is provided.
From Helichrysum splendidum, a plant used traditionally to treat rheumatism, two
monomeric guaianolides and a dimeric guaianolide, helisplendidilactone, were isolated.
The stereochemistry of these known compounds was confirmed and the NMR assignments
for certain peaks of helisplendidilactone were corrected. An X-ray structure for
helisplendidilactone was obtained for the first time.
The phytochemistry of Helichrysum montanum was investigated for the first time and new
diastereoisomers of known guaianolides were isolated. The phytochemistry of H.
splendidum and H. montanum is remarkably similar and supports their morphological
classification in the same taxonomic group. The chloroform:methanol extract of H.
montanum yielded a new dimeric guaianolide, 13’-epihelisplendidilactone, which is related
to helisplendidilactone, as well as three monomeric guaianolides (of which one is a new
diastereomer of a known compound). The extract also yielded spathulenol (a
sesquiterpene), umbelliferone (a coumarin) and 4’,5,7-trihydroxy-3,3’,8-trimethoxyflavone
(a flavonoid).
Thirty-five Helichrysum species were screened for antimicrobial activity against six microorganisms
and a preliminary cytotoxic assay, which included the use of “normal” and
cancer cell lines, was performed. H. excisum was selected for further study based on the
fact that it exhibited promising antimicrobial activity and relative low toxicity.
Furthermore, with the exception of the essential oil, the phytochemistry of this species has
not been investigated. From the aerial parts of H. excisum, five flavonoids, identified as pinocembrin, gnaphaliin,
lepidissipyrone, 5-hydroxy-7,8-dimethoxyflavone and isoscutellarein 7-O-b-glucoside
were isolated. Four of these flavonoids have an unsubstituted B-ring, a phenomenon often
observed in flavonoids isolated from Helichrysum species. The active antimicrobial
component of H. excisum has been identified as lepidissipyrone.
Owing to the interesting biological activities reported for phloroglucinol a-pyrones and the
synthetic challenges associated with these molecules, lepidissipyrone was selected for a
synthetic study. Both the flavanone and pyrone moieties present in lepidissipyrone have
been successfully synthesised. A successful strategy towards the CH2 linker between the
two units has been illustrated. The strategy could be used to synthesise similar
phloroglucinol-derived pyrones. / Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Environmental factors and plant-to-bacteria signals effects on nodulation and nodule development of peaLira Junior, Mario de Andrade. January 2001 (has links)
With the projected increase in global population, unprecedented increases in crop production will be needed and legume crops are one of the primary means of achieving these increases. The legume-Rhizobium symbiosis is the single most important source of biologically fixed nitrogen in agricultural systems but, as a biological system it is complex, and very sensitive to environmental effects, such as available soil nitrogen, soil pH (both high and low), soil salinity and extremes of soil temperature. Each of these may affect the delicate signal exchange process that occurs during symbiosis establishment. To better understand the effect of environmental factors on signal exchange and nodulation, we conducted four experiments, under controlled-environment conditions, with pea (Pisum sativum) as the model legume. The first experiment studied the effects of available nitrogen, the second the effects of low soil pH, the third the effect of soil salinity and the fourth the effects of low soil temperature. In all experiments the plants were inoculated with Rhizobium leguminosarum bv. viceae cells previously treated with 10 x 10-3 M of hesperitin or naringenin, or not treated (control). In all experiments plants were destructively sampled at 10, 20, 30 and 40 days after inoculation (in two experiments samplings were also conducted at 15 DAI), and data on plant and nodule variables were collected. To allow for a better understanding of the effects of flavonoids on nodule development an image analysis technique was developed that permitted us to measure every individual nodule at each sampling. This provided a more precise picture of nodule development over time than would have been possible with previous methods. Our results indicated that addition of flavonoids had positive effects on nodulation, both in number and size of nodules produced, and that the positive effects were greatest at the most inhibitory levels of the environmental factors tested, and at earlier sampling
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Aspects of the gastrointestinal uptake and metabolism of luteolin derivatives from Artemisia afra aqueous extract (preclinical)Mukinda, James Tshikosa January 2011 (has links)
The aim of this study was to investigate the effect the plant matrix and the structure of the flavonoid (i.e. whether aglycone or glycoside) may have on the gastrointestinal uptake and metabolism of luteolin derivatives from Artemisia afra traditional plant medicine. Specifically, how these two factors influenced the intestinal uptake and disposition of luteolin derivatives in pure and in Artemisia afra plant extract forms were to be assessed by investigating the uptake and metabolism of the luteolin derivatives in human intestinal epithelial Caco-2 cells and the perfused rat intestinal loop. To realize this aim, the following were determined: (1) identification and characterization of major luteolin derivatives found in Artemisia afra, (2) the effect of the plant matrix on the uptake of luteolin derivatives in Artemisia afra aqueous-extract forms across the Caco-2 cell monolayer, (3) the effect of the plant matrix on the absorption and metabolism of luteolin derivatives in Artemisia afra aqueous-extract forms in the perfused rat small intestine, (4) the effect of gut contents on the uptake and metabolism of luteolin derivatives in intestinal loop and (5) the metabolic profiles of luteolin derivatives obtained for the pure solutions versus plant aqueous extract solutions in Caco-2 cells and the rat intestine. / Philosophiae Doctor - PhD
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Neuroprotective effects of amantadine–flavonoid conjugates / Fourie P.M.Fourie, Petrus Michiel January 2011 (has links)
Neurodegenerative disorders like Parkinson’s and Alzheimer’s disease affect millions of
people around the world. Oxidative stress has been implicated in the pathogenesis of a
number of neurodegenerative disorders, cancer and ischemia. The brain is particularly
vulnerable to oxidative damage because of its high utilisation of oxygen, high levels of
polyunsaturated fatty acids, relatively high levels of redox transition metal ions and low levels
of antioxidants. Oxidative stress occurs due to an imbalance in the pro–oxidant and
antioxidant levels. Reactive oxygen/nitrogen species (ROS/RNS) is a collective term used
for free radicals and related molecules, promoting oxidative stress within cells and ultimately
leading to neurodegeneration. Antioxidants counteract the excess in ROS/RNS, and is
therefore of interest in the treatment and prevention of neurodegenerative disorders.
Monoamine oxidases, especially monoamine oxidase B (MAO–B), also play an important role
in neurodegenerative disorders. MAO–B is the main enzyme responsible for the oxidative
deamination of dopamine in the substantia nigra of the brain. By inhibiting MAO–B,
dopamine is increased in the brain providing symptomatic relief in Parkinson’s disease.
The focus of the current study was to synthesise multifunctional compounds that could be
used in the treatment and/or prevention of neurodegenerative diseases. In this study
flavonoids were selected because of their wide spectrum of biological activities, including
antioxidant activity and its monoamine oxidase inhibition. Flavones and chalcones are both
classified under flavonoids and both structures were included. The amantadine moiety was
included because of its known ability to inhibit calcium flux through the N–methyl–D–aspartate
(NMDA) receptor channel. Six amantadine–flavonoid derivatives were synthesised using
standard laboratory procedures and structures were determined with standard methods such
as NMR, IR and mass spectrometry. The synthesised compounds were tested in a selection
of biological assays, to establish the relative antioxidant properties and MAO inhibitory
activity.
The biological assays employed to test antioxidant properties were the thiobarbituric acid
(TBA) and nitro–blue tetrazolium (NBT) assays. The TBA assay relies on the assessment of
lipid peroxidation, induced via hydroxyl anions (OH), generating a pink colour with the
complex formation between malondialdehyde (MDA) and TBA, which is measured
spectrophotometrically at 532 nm. The principal of the NBT assay is the reduction of NBT to
nitro–blue diformazan (NBD), producing a purple colour in the presence of superoxide anions
(O2
–).
The synthesised compounds were also evaluated for their MAO inhibitory activity toward
recombinant human MAO–A and -B and inhibition values were expressed as IC50 values.
The experimental data obtained in the NBT and TBA assay indicated a weak but a significant
ability to scavenge O2
– and OH. In the NBT assay N–(adamantan–1–yl)–2–{3–hydroxy–4–[(2E)–
3–(3–methoxyphenyl)pro–2–enoyl]phenoxy}acetamide (6) had the best results with a 50.47 ±
1.31 uM/mg protein reduction in NBD formation, indicating that the hydroxyl group
contributed to activity. The synthesised compounds were compared to the toxin (KCN) with
a reduction in NDB formation of 69.88 ± 1.59 uM/mg protein. Results obtained from the TBA
assay indicated that the flavone moiety had better OH scavenging ability than that of the
chalcone moiety with N–(adamantan–1–yl)–2–[(5–hydroxy–4–oxo–2–phenyl–4H–chromen–7–
yl)oxy]acetamide (3) showing the best activity at 0.967 ± 0.063 nmol MDA/mg tissue. The
synthesised compounds were compared to the toxin (H2O2) 1.316 ± 0.028 nmol MDA/mg
tissue. None of the test compounds could be compared to the results obtained with Trolox®.
The IC50 values obtained for inhibition of recombinant human MAO indicated that the
chalcone moiety (N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–phenylpro–1–en–1–yl]benzamide (5))
showed the best inhibition of MAO–B with an IC50 of 0.717 ± 0.009 M and of MAO–A with an
IC50 of 24.987 ± 5.988 M. It was further confirmed that N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–
phenylpro–1–en–1–yl]benzamide (5) binds reversible to MAO–B and that the mode of inhibition
is competitive. Docking studies revealed that N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–phenylpro–
1–en–1–yl]benzamide (5) traverses both cavities of MAO–B with the chalcone moiety
orientated towards the FAD co–factor while the amantadine moiety protrudes into the
entrance cavity. / Thesis (M.Sc. (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2012.
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Neuroprotective effects of amantadine–flavonoid conjugates / Fourie P.M.Fourie, Petrus Michiel January 2011 (has links)
Neurodegenerative disorders like Parkinson’s and Alzheimer’s disease affect millions of
people around the world. Oxidative stress has been implicated in the pathogenesis of a
number of neurodegenerative disorders, cancer and ischemia. The brain is particularly
vulnerable to oxidative damage because of its high utilisation of oxygen, high levels of
polyunsaturated fatty acids, relatively high levels of redox transition metal ions and low levels
of antioxidants. Oxidative stress occurs due to an imbalance in the pro–oxidant and
antioxidant levels. Reactive oxygen/nitrogen species (ROS/RNS) is a collective term used
for free radicals and related molecules, promoting oxidative stress within cells and ultimately
leading to neurodegeneration. Antioxidants counteract the excess in ROS/RNS, and is
therefore of interest in the treatment and prevention of neurodegenerative disorders.
Monoamine oxidases, especially monoamine oxidase B (MAO–B), also play an important role
in neurodegenerative disorders. MAO–B is the main enzyme responsible for the oxidative
deamination of dopamine in the substantia nigra of the brain. By inhibiting MAO–B,
dopamine is increased in the brain providing symptomatic relief in Parkinson’s disease.
The focus of the current study was to synthesise multifunctional compounds that could be
used in the treatment and/or prevention of neurodegenerative diseases. In this study
flavonoids were selected because of their wide spectrum of biological activities, including
antioxidant activity and its monoamine oxidase inhibition. Flavones and chalcones are both
classified under flavonoids and both structures were included. The amantadine moiety was
included because of its known ability to inhibit calcium flux through the N–methyl–D–aspartate
(NMDA) receptor channel. Six amantadine–flavonoid derivatives were synthesised using
standard laboratory procedures and structures were determined with standard methods such
as NMR, IR and mass spectrometry. The synthesised compounds were tested in a selection
of biological assays, to establish the relative antioxidant properties and MAO inhibitory
activity.
The biological assays employed to test antioxidant properties were the thiobarbituric acid
(TBA) and nitro–blue tetrazolium (NBT) assays. The TBA assay relies on the assessment of
lipid peroxidation, induced via hydroxyl anions (OH), generating a pink colour with the
complex formation between malondialdehyde (MDA) and TBA, which is measured
spectrophotometrically at 532 nm. The principal of the NBT assay is the reduction of NBT to
nitro–blue diformazan (NBD), producing a purple colour in the presence of superoxide anions
(O2
–).
The synthesised compounds were also evaluated for their MAO inhibitory activity toward
recombinant human MAO–A and -B and inhibition values were expressed as IC50 values.
The experimental data obtained in the NBT and TBA assay indicated a weak but a significant
ability to scavenge O2
– and OH. In the NBT assay N–(adamantan–1–yl)–2–{3–hydroxy–4–[(2E)–
3–(3–methoxyphenyl)pro–2–enoyl]phenoxy}acetamide (6) had the best results with a 50.47 ±
1.31 uM/mg protein reduction in NBD formation, indicating that the hydroxyl group
contributed to activity. The synthesised compounds were compared to the toxin (KCN) with
a reduction in NDB formation of 69.88 ± 1.59 uM/mg protein. Results obtained from the TBA
assay indicated that the flavone moiety had better OH scavenging ability than that of the
chalcone moiety with N–(adamantan–1–yl)–2–[(5–hydroxy–4–oxo–2–phenyl–4H–chromen–7–
yl)oxy]acetamide (3) showing the best activity at 0.967 ± 0.063 nmol MDA/mg tissue. The
synthesised compounds were compared to the toxin (H2O2) 1.316 ± 0.028 nmol MDA/mg
tissue. None of the test compounds could be compared to the results obtained with Trolox®.
The IC50 values obtained for inhibition of recombinant human MAO indicated that the
chalcone moiety (N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–phenylpro–1–en–1–yl]benzamide (5))
showed the best inhibition of MAO–B with an IC50 of 0.717 ± 0.009 M and of MAO–A with an
IC50 of 24.987 ± 5.988 M. It was further confirmed that N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–
phenylpro–1–en–1–yl]benzamide (5) binds reversible to MAO–B and that the mode of inhibition
is competitive. Docking studies revealed that N–(adamantan–1–yl)–4–[(1E)–3–oxo–3–phenylpro–
1–en–1–yl]benzamide (5) traverses both cavities of MAO–B with the chalcone moiety
orientated towards the FAD co–factor while the amantadine moiety protrudes into the
entrance cavity. / Thesis (M.Sc. (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2012.
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Šermukšnio (Sorbus L.) genties augalų fenolinių junginių tyrimas / Research of Phenolic Compounds in Plants of Genus Sorbus LGaivelytė, Kristina 04 September 2014 (has links)
Sorbus L. gentis yra plačiai paplitusi pasaulyje. Šermukšnio genties augalų augalinės žaliavos fitocheminė sudėtis tiriama pasaulio mokslininkų, tačiau duomenys apie galimą fenolinių junginių įvairavimą yra nepakankami. Siekiant ištirti Lietuvoje natūraliai augančių ir auginamų kolekcijose šermukšnių (Sorbus L.) rūšių ir veislių lapų, žiedų ir vaisių flavonoidų ir fenolinių rūgščių kokybinės ir kiekinės sudėties įvairavimą, optimizuota efektyviosios skysčių chromatografijos (ESC) metodika. Ištirta paprastųjų šermukšnių (S. aucuparia L.) lapų, žiedų ir vaisių ėminių flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis bei nustatyti įvairavimo ypatumai augalo vegetacijos periodo metu. Ištirta Lietuvoje natūraliose augavietėse augančių S. aucuparia L. lapų ėminių flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis. Nustatyta kolekcijose auginamų Sorbus L. genties rūšių ir veislių augalų flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis bei jų kaupimosi dėsningumai. Atlikti Sorbus L. genties rūšių ir veislių vaisių fenolinių junginių antioksidacinio aktyvumo tyrimai taikant pokolonėlinės reakcijos metodą, nustatytas ryšys tarp fenolinių junginių kiekio šermukšnių vaisiuose ir antioksidacinio aktyvumo. / Sorbus L. genus is widespread in the world. In the course of research carried out in various countries, analysis of the phytochemical composition of Sorbus L. species has been performed, however, information about possible variation of phenolic compounds is insufficient. In order to investigate qualitative and quantitative composition of phenolic acids and flavonoids in leaves, inflorescences and fruits of Sorbus L. growing in natural habitats and grown in collection in Lithuania HPLC method was developed. Variation patterns of the contents of phenolic compounds flavonoids in leaves, inflorescences and fruits of S. aucuparia L. during the growth season were determined. Qualitative and quantitative composition of phenolic acids and flavonoids in leaves of S. aucuparia L. growing in natural habitats in Lithuania was investigated. Qualitative and quantitative composition of phenolic acids and flavonoids of species and varieties of genus Sorbus L. plants, grown in collections, was investigated. Antioxidant activity of fruits of species and varieties of genus Sorbus L. was investigated applying postcolumn HPLC method and relationship between the amount of phenolic compounds and antioxidant activity was revealed.
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Antilipideminėmis savybėmis pasižyminčių vaistinių augalų veikliųjų medžiagų palyginamoji apžvalga ir raudonųjų dobilų (Trifolium pratense L.) žolės pritaikymo mažinti cholesterolio kiekį kraujyje pagrindimas / The comparative overview of antilipidemic active compounds from medicinal herbs and evaluation of red clover (Trifolium pretense L.) application for lowering cholesterol in bloodBercevič, Renata 28 June 2011 (has links)
Darbo tikslas – apžvelgti Lietuvoje augančių antilipideminėmis savybėmis pasižyminčių augalų pritaikymo galimybes mažinti cholesterolio kiekį kraujyje bei pagrįsti raudonųjų dobilų terapinį potencialą.
Tyrimo metodai. Bendrasis flavonoidų kiekis raudonųjų dobilų žolėje nustatytas UV spektrofotometrijos metodu. Raudonųjų dobilų veikliųjų medžiagų ADME savybių prognozė atlikta panaudojant ACD/ADME suite 5.0 programą. Statistinė analizė atlikta naudojant „Microsoft Office Excel 2003“ programą. Apskaičiuotas aritmetinis vidurkis ir standartinis nuokrypis.
Tyrimo rezultatai. Daugiausia flavonoidų raudonųjų dobilų žaliavoje yra birželio mėn. pradžioje ir viduryje (0,46 ± 0,07 proc.). Liepos mėn. pradžioje flavonoidų kiekis sumažėja 2–3 kartus, o vasaros viduryje padidėja iki 0,33 ± 0,05 proc. Rugpjūčio mėnesį flavonoidų kiekis žaliavoje vėl sumažėja iki 0,29 ± 0,03 proc. Remiantis programos prognozėmis raudonųjų dobilų žolės veikliosios medžiagos pasižymi gana palankiomis ADME savybėmis, kurios leistų šio augalo preparatus vartoti per os. Dauguma veikliųjų junginių, ypač flavonoidų aglikonai ir kumarinai turėtų labai gerai absorbuotis pasyviosios absorbcijos būdu, o didžiausias bioprieinamumas per os (> 70 proc.) prognozuojamas biochaninui A, daidzeinui, formononetinui ir kumestroliui. Beveik visoms veikliosioms medžiagoms, kaip ir statinams, prognozuojamas nedidelis pasiskirstymo tūris: nuo 0,7 l/kg iki 1,6 kg/l. Visiems junginiams prognozuojamos labai mažos tikimybės, kad jie... [toliau žr. visą tekstą] / Objectives – to overview the possibility to use plants with antilipidemic properties growing in Lithuania to reduce cholesterol in blood and to substantiate therapeutic potential of the red clover.
Methods. Total flavonoid amount in red clover was determined by using UV spectroscopy. ADME properties of red clover active substances were predicted by using ACD/ADME suite 5.0 software. Statistical analysis was carried out using “Microsoft Office Excel 2003” software. Arithmetical average and standard deviation were calculated.
Results. The biggest amount of flavonoids in red clover raw material is detected in the beginning and middle of June (0.46 ± 0.07 %). The content of flavonoids decreases two-three times in the beginning of July, and increases to 0.33 ± 0.05 % in the middle of the summer. The flavonoid content of raw material decreases to 0.29 ± 0.03 % again in August.
Based on program predictions the active substances present in the herb of red clover have beneficial ADME properties affording the preparations of this herb to use per os. Majority of active substances, especially flavonoid aglycones and coumarins should have very good absorption by passive route of absorption, and the highes oral bioavailability (>70 %) is predicted for biochanin A, daidzein, formononetin and coumestrol. Almost all active compounds, the same as statins, were predited to have low volume of distribution: from 0.7 l/kg to 1.6 l/kg. All compounds were prognosed not to be strong inhibitors of CYP... [to full text]
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Fenolinių junginių kiekinės sudėties tyrimas Lietuvoje auginamų obelų veislių skirtingų poskiepių ir kultivavimo sistemų obuoliuose / Study of quantitative composition of phenolic compounds in Lithuania grown apples from different rootstocks and cultivation systemsBudrys, Evaldas 18 June 2014 (has links)
Ištirti Lietuvoje auginamų obelų veislių skirtingų poskiepių ir kultivavimo sistemų obuolių fenolinių junginių kiekinės sudėties įvairovę bei įvertinti antioksidantinį aktyvumą. / To evaluate quantitative composition and antioxidant activity of phenolic compounds in Lithuania grown apples from different rootstocks and cultivation systems.
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Fenolinių junginių kokybinės ir kiekybinės sudėties įvairavimo šermukšnių (S. aucuparia l.) lapuose ir žieduose tyrimas / Qualitative and quantitative study of phenolic compounds variation in S.aucuparia L. leaves and flowersVaitūnaitytė, Malvina 30 June 2014 (has links)
Tyrimo objektas ir metodai: Sorbus L. genties augalo S. aucuparia L. lapų ir žiedų tyrimas. Bendras fenolinių junginių kiekis paprastojo šermukšnio augalinėse žaliavose nustatytas UV spektrofotometriniu metodu, fenolinės rūgštys ir flavonoidai nustatyti ESC metodu.
Darbo tikslas: nustatyti S. aucuparia L. lapuose ir žieduose esančius fenolinius junginius, jų kiekinės sudėties įvairavimą augalo vegetacijos metu ir augalinių žaliavų (lapų ir žiedų) laikymo metu.
Darbo uždaviniai: Surinkti ir susisteminti literatūros duomenis apie Sorbus aucuparia L., paprastojo šermukšnio augalinių žaliavų cheminę sudėtį, fenolinių junginių analizės metodus, poveikį ir panaudojimą medicinos praktikoje; Ištirti S. aucuparia L. lapų ir žiedų kiekybinę fenolinių junginių sudėtį ir nustatyti bendro fenolinių junginių kiekio įvairavimą augalo vegetacijos metu; Ištirti S. aucuparia L. lapų ir žiedų kokybinę ir kiekybinę fenolinių rūgščių ir flavonoidų sudėtį ir nustatyti jų kiekinės sudėties kitimą augalų vegetacijos periodo metu; Nustatyti S. aucuparia L. lapuose ir žieduose esančių fenolinių junginių kiekybinės sudėties kitimus augalinių žaliavų laikymo metu.
Išvados: S. aucuparia L. augalinės žaliavos gali būti kaip šaltinis išskiriant biologiškai aktyvius junginius, kurie gali būti naudojami medicinos praktikoje. S. aucuparia L. lapuose ir žieduose esančių junginių kiekis kinta augalo vegetacijos metu; lapuose daugiausia fenolinių junginių sukaupiama gegužės - birželio mėn., žieduose – žydėjimo... [toliau žr. visą tekstą] / Object and methods: Sorbus aucuparia L. leaves and flowers study. Total amaunt of phenolic compounds in mountain ash leaves and flowers were evaluated using UV spectrophotometry, phenolic acids and flavonoids were identified and evaluated using HPLC.
Aim: to identify and evaluate the content of phenolic compounds in rowan leaves and flowers during mountain ash vegetation and during plant materials (leaves and flowers) storage.
Objective: to collect and organise the information about the use of Sorbus aucuparia L., S. aucuparia L. leaves and flowers acumulated compounds, phenolic compounds analysis methods and the impact of the use in medical practice; to perform quantitative analysis of S. aucuparia L. leaves and flowers phenolic compounds and to determine the total phenolics content during rowan growing season; to perform qualitative and quantitative analysis of S. aucuparia L. leaves and flowers phenolic acids and flavonoids and to determine the variation of the phenolics content during rowan growing season; to determine phenolic compounds content changes in Sorbus aucuparia L. plant materials (flowers and leaves) during them storage.
Conclusions: S. aucuparia L. leaves and flower is a source of biological active substances which can be used in medicinal practice. Phenolic compounds content in S. aucuparia L. leaves and flowers change during vegetation; mainly phenolic compounds in leaves was accumulated in May - June, in flowers - in the beginning of flowering and massive... [to full text]
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Pelkinių vingiorykščių (Filipendula ulmaria L.) augalinės žaliavos cheminės sudėties, antiradikalinio ir antimikrobinio poveikių įvertinimas / Chemical composition, antiradical and antimicrobial effect assessment of Meadowsweet (Filipendula ulmaria L.) herbal raw materialŽemaitytė, Rūtelė 30 June 2014 (has links)
Tikslas: įvertinti pelkinių vingiorykščių (Filipendula ulmaria L.) cheminę sudėtį ir antimikrobinį poveikį. Uždaviniai: nustatyti tinkamiausią ekstrakcijos metodą ir optimalias ekstrakcijos sąlygas; įvertinti flavonoidų, askorbo rūgšties ir raugų kiekybinės sudėties kitimo dinamiką augalo vegetacijos metu; įvertinti vaistinės augalinės žaliavos antimikrobinį poveikį prieš devynias mikroorganizmų kultūras; nustatyti vaistinės augalinės žaliavos antiradikalinio aktyvumo priklausomybę nuo augalo vegetacijos tarpsnio ir nustatyti, ar yra priklausomybė tarp flavonoidų, raugų ir askorbo rūgšties kiekio vaistinėje augalinėje žaliavoje ir antiradikalinio jos poveikio. Ekstrakcijai pasirinkta maceracija ultragarsinėje vonelėje, kaip ekstrahentą naudojant 70 proc. V/V etanolį. Suminiam flavonoidų kiekiui nustatyti taikytas spektrofotometrinis suminio flavonoidų kiekio įvertinimo metodas. Suminiam raugų kiekiui ir askorbo rūgšties kiekiui nustatyti taikyti farmakopėjiniai titrimetrijos metodai. Antimikrobinis poveikis įvertintas liejant skirtingas tirštųjų ekstraktų koncentracijas į agarą ir stebint mikrooroganizmų augimą, o antiradikalinis aktyvumas nustatytas taikant ABTS radikalo surišimo metodą. Didžiausias suminis flavonoidų kiekis aptiktas augalo masinio žydėjimo metu. Pirmojoje fenologinio vystymosi pusėje askorbo rūgšties kiekis buvo didesnis už vidutinį per visą vaistinio augalo vegetacijos laikotarpį (>0,025 proc.). Suminio raugų kiekio maksimumas pasiektas prieš pelkinių... [toliau žr. visą tekstą] / Objective: To assess chemical composition and biological effects of meadosweet (Filipendula ulmaria L.) Objectives: To determine the most suitable extraction method and the optimum extraction conditions; evaluation of quantitative composition dynamics of flavonoids, tannins and ascorbic acid during the growing season; antimicrobial effects evaluation of herbal ingredients against nine microbial cultures; evaluate dependence antiradical activity on the growing stage of the plant and to determine whether there is a relationship between quantity of flavonoids, tannins and ascorbic acid in the herbal raw material and its antiradical effect. The maceration by ultrasonic bath using 70 %. V / V ethanol was selected for extraction . For total flavonoids determination the spectrophotometric method was applied for total flavonoid content. For total tannin content and content of ascorbic the pharmacopoeial titration methods were applied. The antimicrobial effects were evaluated by infusing different concentrations of extractives to agar and observing microorganisms growth. The antiradical activity determined using the ABTS radical scavaning method. The highest total flavonoid content was found in massive flowering period. In the first half of the phenological development ascorbic acid content was higher than the average of the entire period of growing (> 0.025 %.). The peak of total tannin content was reached before massive flowering stage of meadowsweet (16.80 %). The ethanol... [to full text]
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