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TLC-DPPH• activity-guided separation and LC-DAD-MS identification of antioxidant compounds from Mutellina purpurea L. herb

Sieniawska E., Baj T., Dudka J., Mroczek T., Głowniak K.

Acta Chromatographica

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2016

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Vol. 28, no. 1

51--58

EN

Many phytochemical investigations have been focused recently on the antioxidant activity of herbal extracts which can be used in phytotherapy. The previous study revealed antioxidative properties of Mutellina purpurea extract, but the constituents responsible for this action were not described yet. The aim of this study was activityguided separation and identification of antioxidant compounds from M. purpurea herb. Thin-layer chromatography-2,2-diphenyl-1-picrylhydrazyl (TLC-DPPH•) assay was used to detect compounds of interest; liquid chromatography-diode array detection-mass spectrometry (LC-DAD-MS) analysis allowed to identify antioxidants. The active fractions analyzed with LC-DAD-MS contained as a main compound chlorogenic acid accompanied with p-coumaric acid, ferulic acid, three dicaffeoylquinic acids, and caffeoylferuloylquinic acid. The fast TLC-DPPH• assay with LC-DAD-MS identification enabled the accurate identification of antioxidants in M. purpurea herb, which was done for the first time.

2

HPLC, Two-Dimensional TLC Determination of Phenolic Content, and an In Vitro Perspective to Antioxidant Potential of Euonymus verrucosus Scop. Extracts

Kukula-Koch W., Widelski J., Koch W., Głowniak K.

Acta Chromatographica

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2015

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Vol. 27, no. 4

743--754

EN

The presence of phenolic content in overground extracts of Euonymus verrucosus Scop. — commonly growing in Europe — has been reported recently. The chromatographical and spectral data revealed the presence of several simple phenolic acids (gallic, protocatechuic, p-hydroxybenzoic, vanillic, syringic, caffeic, p-coumaric, ferulic, and m-coumaric acids), both as free and conjugated with other secondary metabolites. The comparison of two-dimensional TLC systems on cellulose stationary phases with HPLC— DAD reversed-phase chromatography was performed to assess a cheap and rapid technique in the identification process of major phenolic constituents. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging tests, expressed as IC50, revealed the most beneficial results for the fraction after alkaline hydrolysis and yielded 205 ± 8 μg mL−1.

3

Computer-assisted searching for coumarins in Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap.

Skalicka-Woźniak K., Markowski W., Świeboda R., Głowniak K.

Acta Chromatographica

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2009

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Vol. 21, no. 4

531--546

EN

The objective of the work was continuation of our study on identification of target coumarins in extracts from Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap., by use of ChromSword, on the basis of relationships between retention data and descriptors such as partial molecular volume of structural fragments in water and energies of electrostatic interactions of bond dipoles with water (QSRR). The coumarins were mainly identified by comparing UV spectra from gradient runs with spectra from the literature. The presence of columbianadin, ostruthin, and 8-methoxypeucedanin in the fruits of P. cervaria (L.) Lap. and oxypeucedanin and isoimperatorin in the fruits of P. alsaticum was confirmed. The optimum conditions obtained from DryLab simulation were used for both RP-HPLC and RP-UPLC.

4

Variation of the volatile content of the fruits of Peucedanum alsaticum L.

Skalicka-Woźniak K., Łoś R., Głowniak K., Malm A.

Acta Chromatographica

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2008

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Vol. 20, no. 1

119-133

EN

Volatile compounds from fruits of Peucedanum alsaticum L. were isolated by hydrodistillation (HD) and headspace solid-phase microextraction (HS-SPME), and then analyzed by GC-MS. The predominant volatile compounds were α-pinene, sabinene, limonene, and β-phellandrene (more than 60% of the oil). The β-pinene, β-myrcene, camphene, β-caryophyllene, bornyl acetate, and germacrene D content was also high. The in-vitro antibacterial activity of the essential oil and some of its components against ten reference strains of Gram-positive and Gram-negative bacteria was evaluated by the agar dilution method. The essential oil and the compounds were more active against Gram-positive than Gram-negative bacteria.

5

Screening for phenolic acids in five species of Iris collected in Mongolia

Machalska A., Skalicka-Woźniak K., Widelski J., Głowniak K., Purevsuren G., Oyun Z., Khishgee D., Urjin B.

Acta Chromatographica

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2008

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Vol. 20, no. 2

259-267

EN

Five species of Iris commonly used in Mongolian traditional medicine (Iris dichotoma Pall., Iris flavissima Pall., Iris bungei Maxim., Iris lactea Pall., and Iris tenuifolia Pall.) were analyzed for the presence of phenolic acids. This was the first study of the phenolic acid content of these species. Samples containing the phenolic acids were prepared by the method of Świątek and then analysed by HPLC with UV-visible diodearray detection (DAD). Identification was performed by comparing retention times with those of standards. Quantitative determination was performed at the absorbance maximum of each phenolic acid (320 nm for ferulic, p-coumaric, and caffeic acids, 280 nm for trans-cinnamic, syringic, and gallic acids, and 254 nm for vanillic, m-hydroxybenzoic, phydroxybenzoic, and protocatechuic acids). As the result of our study ten phenolic acids, both free and liberated by alkaline and acid hydrolysis, were identified by HPLC. Chromatographic investigation revealed the presence of vanillic acid, protocatechuic acid, trans-cinnamic acid, p-hydroxybenzoic acid, p-coumaric acid, ferulic acid, gallic acid, syringic acid, m-hydroxybenzoic acid, and caffeic acid. Quantitative analysis of these acids was also performed. Finally, the presence or absence of some phenolic acids after alkaline or acid hydrolysis was also observed.

6

Furanocoumarins from Peucedanum tauricum Bieb. and their variability in the aerial parts of the plant during development

Bartnik M., Głowniak K.

Acta Chromatographica

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2007

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No. 18

5-14

EN

A rapid and sensitive reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been used for determination of furanocoumarins in methanolic extracts of Peucedanum tauricum Bieb. HPLC separation was performed on a C18 analytical column (250 mm × 4 mm i.d., 5-μm particles) with a methanol–water gradient as mobile phase. A second chromatographic system with an acetonitrile–water gradient was also developed independently. Diode-array detection was performed between 220 and 400 nm and in quantitative analysis compounds were detected at 320 nm. Calibration plots were linear for 0.01–0.2 mg mL-1 bergapten and peucedanin in methanol (injection volume 10 μL). Before HPLC, samples were purified by solid-phase extraction (SPE). Oxypeucedanin hydrate (oPh), bergapten (5-MOP), oxypeucedanin (oP), peucedanin (P), 8-methoxypeucedanin (mP), and isoimperatorin (isoIMP) were detected and identified in extracts of P. tauricum. Total amounts of furanocoumarins determined by SPE–HPLC were 8.31 mg g-1 dry wt (0.83%) in flowers, 20.49 mg g-1 dry wt (2.05%) in immature fruits, and 21.30 mg g-1 dry wt (2.13%) in mature fruits. The predominant coumarin compound in the reproductive organs was peucedanin – 5.04 mg g-1 dry wt (0.50%) in flowers, 13.58 mg g-1 dry wt (1.36%) in immature fruits, and 13.51 mg g-1 dry wt (1.35%) in completely mature fruits. The predominant furanocoumarin in the leaves, however, was 8-methoxypeucedanin – from 0.55 mg g-1 to 1.02 mg g-1 dry wt (0.06–0.10%). The furanocoumarin content of the plant extracts correlated with period of development and the part of the plant (generative or vegetative). Some of the detected compounds (e.g. peucedanin and 8- methoxypeucedanin, which are both linear furanocoumarins of a rare structural type with restricted occurrence in P. officinale and the closely related species P. coriaceum and P. longifolium) could be a chemotaxonomically characteristic of the species investigated. As we have reported elsewhere, peucedanin is effective at induction of apoptosis and inhibition of heatshock protein expression in HeLa cells. The fruits of P. tauricum are a good source of peucedanin for further biological and pharmacological tests.

7

Optimization of extraction of pyrrolizidine alkaloids from plant material

Mroczek T., Widelski J., Głowniak K.

Chemia Analityczna

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2006

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Vol. 51, No. 4

567-580

EN

Various techniques of extraction of pyrrol izidine alkaloids (PAs) from comfrey have been developed and compared. Different extraction media: methanol, ethanol, 1% methanolic solution of tartaric acid, 2.5% HC1 solution, 5% CH.COOH solution, alkaline chloro form- -methanol mixture at various temperatures (room temperature, 50-60°C, solvent's boiling point) have been used in various extraction techniques (percolation, electric basket, ultrasonic water bath) and various extraction times. Total concentration of pyrrolizidine alkaloids (PAs) was estimated from UV-VIS spectrophotometric studies according to Dann- -Mattocks procedure. For the most promising extraction techniques one determined recoveries of monocrotaline added to crude pre-extracts. Extraction and co-extraction processes were investigated using UV-VIS spectra of the adducts of 3,4-dehydro-PAs and Ehrlich's reagent. The best result of PAs extraction from comfrey was obtained using 1% methanolic solution of tartaric acid and electric basket technique at the temperature 100 š 5°C for 2 h. Possible applications of the method have been discussed.

PL

W prezentowanej pracy podjęto badania optymalizacji ekstrakcji alkaloidów pirolizydy-nowych (PAs) z materiału roślinnego (źywokostu lekarskiego). Zastosowane metody obejmowały ekstrakcję metanolem, etanolem, l % roztworem kwasu winowego w metanolu, 2.5% roztworem kwasu solnego, 5% roztworem kwasu octowego, alkaliczną fazą organiczną (chloroform-metanol). Badano również wpływ temperatury ekstrakcji (pokojowa, 50-60°C, wrzący rozpuszczalnik) wykorzystując różne techniki ekstrakcyjne (perkolacja, ekstrakcja w płaszczach grzewczych, ekstrakcja wspomagana ultradźwiękami) oraz wpływ czasu ekstrakcji na odzysk PAs z surowca roślinnego. Caikowitą zawartość PAs oznaczono w oparciu o spektrofotometrię UV-VIS wg metody Danna i Mattocksa. W przypadku najbardziej obiecujących metod ekstrakcji oznaczono odzysk wzorca monokrotaliny dodawanego do pre-ekstraktu tuż przed rozpoczęciem właściwej ekstrakcji. Analizując widma U V—VIS adduktów 3,4-dehydro-PAs z odczynnikiem Ehrlicha możliwa była analiza stopnia ekstrakcji PAs z surowcajak i współekstrakcji substancji balastowych. Najlepszą wydajnością oraz najmniejszym stopniem współekstrakcji balastów charakteryzowała się 2-godzinna ekstrakcja wrzącym (temp. 100 š 5°C) 1% roztworem kwasu winowego w metanolu w płaszczach grzewczych. Przedyskutowano także potencjalne wykorzystanie opracowanej metody.

8

Computer optimization of the rp hplc separation of some taxoids from yew extracts

Hajnos M. Ł., Waksmundzka-Hajnos M., Głowniak K.

Acta Chromatographica

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2002

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No. 12

211-218

EN

Drylab G software has been used to optimize the reversed-phase HPLC separation of taxoids and co-extracted substances from yew. Two preliminary runs based on a linear gradient from 5 to 100% acetonitrile (ACN) in 20 or 60 min were shown to be satisfactory for optimization of resolution. The optimization experiments were performed on a purified extract fortified with taxoid standards. The identity and purity of the peaks were verified by use of photodiode-array detection. Agreement between simulated and experimental data was good. The optimized chromatographic system can be used for quantitative analysis of paclitaxel, cephalomannine, and 10-deacetylbaccatin in yew extracts.

9

Influence of the extraction mode on the yield of taxoids from yew tissues -- preliminary experiments

Hajnos M. Ł., Waksmundzka-Hajnos M., Gawdzik J., Dawidowicz A. L., Głowniak K.

Chemia Analityczna

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2001

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Vol. 46, No. 6

831-838

EN

Different modes of extraction of yew twigs, such as: maceration with methanol at room temperature, extraction with methanol in ultrasonic bath at room temperature, accelerated solvent extraction with methanol at room temperature and at 100°C were compared. The effect of pre-extraction with n-hexane in accelerated solvent extraction (ASE) method was also investigated. The following procedure, before the RP-HPLC analysis of taxoids, was performed: SPE of crude extracts dissolved in dichloromethane using alumina column and elution with dichloromethane-ethyl acetate-methanol in different proportions followed by zonal micropreparative TLC using 0.5 mm layer of silica and elution with multicomponent eluent. The fractions were analysed quantitatively using C]g column and acetonitrile-water (1:1, v/v) mixtures as eluent. The obtained results presented graphically allow to conclude that the best yield of extraction was obtained by ASE method, when methanol at 100°C was used as an extrahent. Comparable results were obtained using extraction in ultrasonic bath with methanol at room temperature.

PL

Porównywano różne metody ekstrakcji gałązek cisa, takie jak: maceracja metanolem w temperaturze pokojowej, ekstrakcja metanolem w płuczce ultradźwiękowej w temperaturze pokojowej oraz ekstrakcja metodą ASE metanolem w temperaturze pokojowej i w temperaturze 100°C. Badano także wpływ pre-ekstrakcji Ť-heksanem na wydajność ekstrakcji metanolem metodą ASE. W celu oczyszczenia surowych ekstraktów stosowano następującą procedurę: ekstrakcję do fazy stałej (SPE) ekstraktów rozpuszczonych w di-chlorometanie przy użyciu kolumienki wypełnionej tlenkiem glinu stosując elucję mieszaniną dichlorometan-octan etylu-metanol w różnych proporcjach oraz pasmową chromatografię mikropreparatywną na cienkich warstwach żelu krzemionkowego przy zastosowaniu wieloskładnikowego eluentu. Frakcje zawierające taksoidy były analizowane ilościowo metodą RP HPLC w układzie: Clg/acetonitryl-woda(l:l, v/v). Najlepszą wydajność ekstrakcji uzyskano metodą ASE przy użyciu metanolu w temperaturze 100°C. Porównywalne wyniki uzyskano stosując ekstrakcję metanolem wspomaganą ultradźwiękami.