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Smejda-Krzewicka A, Mrozowski K, Strzelec K. Effect of Modified and Unmodified Oak Bark (Quercus Cortex) on the Cross-Linking Process and Mechanical, Anti-Aging, and Hydrophobic Properties of Biocomposites Produced from Natural Rubber (NR). MATERIALS (BASEL, SWITZERLAND) 2024; 17:1968. [PMID: 38730774 PMCID: PMC11084775 DOI: 10.3390/ma17091968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/18/2024] [Accepted: 04/19/2024] [Indexed: 05/13/2024]
Abstract
The study explores the novel use of oak bark (Quercus cortex) as a bio-filler in elastomeric composites, aligning with the global trend of plant-based biocomposites. Both modified and unmodified oak bark were investigated for their impact on the physicochemical properties of natural rubber (NR) composites. The bio-filler modified with n-octadecyltrimethoxysilane exhibited enhanced dispersion and reduced aggregates in the elastomeric matrix. NR composites containing more than 20 phr of unmodified and modified oak bark demonstrated an increased degree of cross-linking (αc > 0.21). Mechanical properties were optimal at 10-15 phr of oak bark and the sample with modified bio-filler (10 phr) achieved the highest tensile strength (15.8 MPa). Silanization and the addition of the bio-filler increased the hardness of vulcanizates. The incorporation of oak bark improved aging resistance at least two-fold due to phenolic derivatives with antioxidant properties. Hydrophobicity decreased with added bark, but silanization reversed the trend, making samples with a high content of oak bark the most hydrophobic (contact angle: 129°). Overall, oak bark shows promise as an eco-friendly, anti-aging filler in elastomeric composites, with modification enhancing compatibility and hydrophobicity.
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Affiliation(s)
- Aleksandra Smejda-Krzewicka
- Institute of Polymer and Dye Technology, Faculty of Chemistry, Lodz University of Technology, Stefanowskiego Street 16, 90-537 Lodz, Poland;
| | - Konrad Mrozowski
- Institute of Polymer and Dye Technology, Faculty of Chemistry, Lodz University of Technology, Stefanowskiego Street 16, 90-537 Lodz, Poland;
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Hofmann T, Makk ÁN, Albert L. Extraction of (+)-catechin from oak ( Quercus spp.) bark: Optimization of pretreatment and extraction conditions. Heliyon 2023; 9:e22024. [PMID: 38027666 PMCID: PMC10665808 DOI: 10.1016/j.heliyon.2023.e22024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/31/2023] [Accepted: 11/02/2023] [Indexed: 12/01/2023] Open
Abstract
Oaks (Quercus L., Fagaceae) are a widespread tree species worldwide, and in Hungary they account for nearly 30 % of the forests. Their wood is valuable, but their bark is considered as a by-product. Oak bark, available in large quantities but with no dedicated use, contains a significant amount of valuable extractives. Its (+)-catechin content is around 1 %. (+)-Catechin is mostly used for food industry, medicine and many other industrial purposes, representing a significant financial value. The aim of the present research was to compare the (+)-catechin concentrations in the bark of the most important oak species found in Hungary and to optimize sample pretreatment (conservation) and extraction methods in order to achieve fast and efficient extraction. From these species the highest concentrations were measured in Q. robur and Q. robur ssp. slavonica (8-12 mg (+)-catechin/g dry bark). The combination of microwave sample pretreatment and microwave assisted extraction proved to be the most time- and cost-effective method. The utilization of the extracted bark powder for energetic purposes requires further investigations.
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Affiliation(s)
- Tamás Hofmann
- University of Sopron, Institute of Environmental Protection and Nature Conservation, H-9400, Bajcsy-Zsilinszky Str. 4, Sopron, Hungary
| | - Ádám Nándor Makk
- DMRV Zrt., Division of Environmental and Water Quality Protection, H-2600, Kodály Zoltán Str. 3, Vác, Hungary
| | - Levente Albert
- University of Sopron, Institute of Environmental Protection and Nature Conservation, H-9400, Bajcsy-Zsilinszky Str. 4, Sopron, Hungary
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Mady MS, Ibrahim RR, El-Sayed EK, El-Shazly M, Chen LY, Lai KH, El Shaarawy FS, Moharram FA. UHPLC-MS profiles and antidiarrheal activity of Quercus coccinea münchh. and Quercus robur L. employing in vivo technique. Front Pharmacol 2023; 14:1120146. [PMID: 36874027 PMCID: PMC9982048 DOI: 10.3389/fphar.2023.1120146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/06/2023] [Indexed: 02/19/2023] Open
Abstract
Introduction: Quercus L. genus (Oak) belongs to the family Fagaceae and their galls are used commercially in leather tanning, dyeing, and ink preparation. Several Quercus species were traditionally used to manage wound healing, acute diarrhea, hemorrhoid, and inflammatory diseases. The present study aims to investigate the phenolic content of the 80% aqueous methanol extract (AME) of Q. coccinea and Q. robur leaves as well as to assess their anti-diarrheal activity. Methods: Polyphenolic content of Q. coccinea and Q. robur AME were investigated using UHPLC/MS. The antidiarrheal potential of the obtained extracts was evaluated by conducting a castor oil-induced diarrhea in-vivo model. Result and Discussion: Twenty-five and twenty-six polyphenolic compounds were tentatively identified in Q. coccinea and Q. robur AME, respectively. The identified compounds are related to quercetin, kaempferol, isorhamnetin, and apigenin glycosides and their aglycones. In addition, hydrolyzable tannins, phenolic acid, phenyl propanoides derivatives, and cucurbitacin F were also identified in both species AME of Q. coccinea (250, 500, and 1000 mg/kg) exhibited a significant prolongation in the onset of diarrhea by 17.7 %, 42.6%, and 79.7% respectively while AME of Q. robur at the same doses significantly prolonged the onset of diarrhea by 38.6%, 77.3%, and 2.4 folds respectively as compared to the control. Moreover, the percentage of diarrheal inhibition of Q. coccinea was 23.8%, 28.57%, and 42,86% respectively, and for Q. robur 33.34%, 47.3%, and 57.14% respectively as compared to the control group. Both extracts significantly decreased the volume of intestinal fluid by 27%, 39.78%, and 50.1% for Q. coccinea respectively; and by 38.71%, 51.19%, and 60% for Q. robur respectively as compared to the control group. In addition, AME of Q. coccinea exhibited a peristaltic index of 53.48, 47.18, and 42.28 with significant inhibition of gastrointestinal transit by 18.98%, 28.53%, and 35.95 % respectively; while AME of Q. robur exhibited a peristaltic index of 47.71, 37, and 26.41 with significant inhibition of gastrointestinal transit by 27.72%, 43.89%, and 59.99% respectively as compared with the control group. Notably, Q. robur showed a better antidiarrheal effect in comparison with Q. coccinea and, the highest effect was observed for Q. robur at 1000 mg/kg as it was nonsignificant from the loperamide standard group in all measured parameters.
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Affiliation(s)
- Mohamed S Mady
- Faculty of Pharmacy, Pharmacognosy Department, Helwan University, Cairo, Egypt
| | - Reham R Ibrahim
- Faculty of Pharmacy, Pharmacognosy Department, Helwan University, Cairo, Egypt
| | - Elsayed K El-Sayed
- Faculty of Pharmacy, Pharmacology and Toxicology Department, Helwan University, Cairo, Egypt
| | - Mohamed El-Shazly
- Faculty of Pharmacy, Pharmacognosy Department, Ain-Shams University, Cairo, Egypt
| | - Lo-Yun Chen
- College of Pharmacy, Graduate Institute of Pharmacognosy, Taipei Medical University, Taipei, Taiwan
| | - Kuei-Hung Lai
- College of Pharmacy, Graduate Institute of Pharmacognosy, Taipei Medical University, Taipei, Taiwan.,College of Pharmacy, Ph.D Program in Clinical Drug Development of Herbal Medicine, Taipei Medical University, Taipei, Taiwan.,Taipei Medical University Hospital, Traditional Herbal Medicine Research Center, Taipei, Taiwan
| | | | - Fatma A Moharram
- Faculty of Pharmacy, Pharmacognosy Department, Helwan University, Cairo, Egypt
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Rajpara A, Gandhi N, Bhatt V, Shah MB. Simultaneous determination of epimers (+)-catechin and (‒)-epicatechin in Onosma bracteatum Wall. using high-performance thin-layer chromatography‒mass spectrometry method. JPC-J PLANAR CHROMAT 2022. [DOI: 10.1007/s00764-022-00157-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Flavan-3-ols and Proanthocyanidins in Japanese, Bohemian and Giant Knotweed. PLANTS 2021; 10:plants10020402. [PMID: 33672472 PMCID: PMC7923414 DOI: 10.3390/plants10020402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 11/17/2022]
Abstract
Flavan-3-ols and proanthocyanidins of invasive alien plants Japanese knotweed (Fallopia japonica Houtt.), giant knotweed (Fallopia sachalinensis F. Schmidt) and Bohemian knotweed (Fallopia × bohemica (Chrtek & Chrtkova) J.P. Bailey) were investigated using high performance thin-layer chromatography (HPTLC) coupled to densitometry, image analysis and mass spectrometry (HPTLC–MS/MS). (+)-Catechin, (−)-epicatechin, (−)-epicatechin gallate and procyanidin B2 were found in rhizomes of these three species, and for the first time in Bohemian knotweed. (−)-Epicatechin gallate, procyanidin B1, procyanidin B2 and procyanidin C1 were found in giant knotweed rhizomes for the first time. Rhizomes of Bohemian and giant knotweed have the same chemical profiles of proanthocyanidins with respect to the degree of polymerization and with respect to gallates. Japanese and Bohemian knotweed have equal chromatographic fingerprint profiles with the additional peak not present in giant knotweed. Within the individual species giant knotweed rhizomes and leaves have the most similar fingerprints, while the fingerprints of Japanese and Bohemian knotweed rhizomes have additional peaks not found in leaves. Rhizomes of all three species proved to be a rich source of proanthocyanidins, with the highest content in Japanese and the lowest in Bohemian knotweed (based on the total peak areas). The contents of monomers in Japanese, Bohemian and giant knotweed rhizomes were 2.99 kg/t of dry mass (DM), 1.52 kg/t DM, 2.36 kg/t DM, respectively, while the contents of dimers were 2.81 kg/t DM, 1.09 kg/t DM, 2.17 kg/t DM, respectively. All B-type proanthocyanidins from monomers to decamers (monomers—flavan-3-ols, dimers, trimers, tetramers, pentamers, hexamers, heptamers, octamers, nonamers and decamers) and some of their gallates (monomer gallates, dimer gallates, dimer digallates, trimer gallates, tetramer gallates, pentamer gallates and hexamer gallates) were identified in rhizomes of Bohemian knotweed and giant knotweed. Pentamer gallates, hexamers, hexamer gallates, nonamers and decamers were identified for the first time in this study in Bohemian and giant knotweed rhizomes.
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Jug U, Naumoska K, Vovk I. (-)-Epicatechin-An Important Contributor to the Antioxidant Activity of Japanese Knotweed Rhizome Bark Extract as Determined by Antioxidant Activity-Guided Fractionation. Antioxidants (Basel) 2021; 10:antiox10010133. [PMID: 33477734 PMCID: PMC7832395 DOI: 10.3390/antiox10010133] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 01/12/2021] [Accepted: 01/14/2021] [Indexed: 01/14/2023] Open
Abstract
The antioxidant activities of Japanese knotweed rhizome bark extracts, prepared with eight different solvents or solvent mixtures (water, methanol, 80% methanol(aq), acetone, 70% acetone(aq), ethanol, 70% ethanol(aq), and 90% ethyl acetate(aq)), were determined using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging assay. Low half maximal inhibitory concentration (IC50) values (2.632–3.720 µg mL−1) for all the extracts were in the range of the IC50 value of the known antioxidant ascorbic acid at t0 (3.115 µg mL−1). Due to the highest extraction yield (~44%), 70% ethanol(aq) was selected for the preparation of the extract for further investigations. The IC50 value calculated for its antioxidant activity remained stable for at least 14 days, while the IC50 of ascorbic acid increased over time. The stability study showed that the container material was of great importance for the light-protected storage of the ascorbic acid(aq) solution in a refrigerator. Size exclusion–high-performance liquid chromatography (SEC-HPLC)–UV and reversed phase (RP)-HPLC-UV coupled with multistage mass spectrometry (MSn) were developed for fractionation of the 70% ethanol(aq) extract and for further compound identification, respectively. In the most potent antioxidant SEC fraction, determined using an on-line post-column SEC-HPLC-DPPH assay, epicatechin, resveratrol malonyl hexoside, and its in-source fragments (resveratrol and resveratrol acetyl hexoside) were tentatively identified by RP-HPLC-MSn. Moreover, epicatechin was additionally confirmed by two orthogonal methods, SEC-HPLC-UV and high-performance thin-layer chromatography (HPTLC) coupled with densitometry. Finally, the latter technique enabled the identification of (−)-epicatechin. (−)-Epicatechin demonstrated potent and stable time-dependent antioxidant activity (IC50 value ~1.5 µg mL−1) for at least 14 days.
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Affiliation(s)
- Urška Jug
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia;
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Katerina Naumoska
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia;
- Correspondence: (K.N.); (I.V.); Tel.: +386-1476-0521 (K.N.); +386-1476-0341 (I.V.)
| | - Irena Vovk
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia;
- Correspondence: (K.N.); (I.V.); Tel.: +386-1476-0521 (K.N.); +386-1476-0341 (I.V.)
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7
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Jug U, Vovk I, Glavnik V, Makuc D, Naumoska K. Off-line multidimensional high performance thin-layer chromatography for fractionation of Japanese knotweed rhizome bark extract and isolation of flavan-3-ols, proanthocyanidins and anthraquinones. J Chromatogr A 2020; 1637:461802. [PMID: 33383239 DOI: 10.1016/j.chroma.2020.461802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/01/2020] [Accepted: 12/12/2020] [Indexed: 10/22/2022]
Abstract
A methodology based on off-line multidimensional thin-layer chromatography was developed for isolation of several secondary metabolites from bark of Japanese knotweed (Fallopia japonica Houtt.) rhizomes. Successive fractionation steps using PLC silica gel and HPTLC silica gel or HPTLC cellulose plates in combination with various developing solvents enabled isolation of (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, procyanidin B1, procyanidin B2, procyanidin B3, proanthocyanidin B dimer gallate, emodin, emodin-8-O-glucoside and emodin-8-O-malonyl-glucoside. Their identity was confirmed by HPTLC, HPTLC-MSn and for most of them also by 1H NMR and 2D NMR analyses. To the best of our knowledge emodin-8-O-malonyl-glucoside, procyanidins B1 and B2 were for the first time isolated from this plant material. HPTLC and HPTLC-MSn analyses were also performed as support of fractionation/isolation process, leading to first detection of some compounds in bark of Japanese knotweed rhizomes and Japanese knotweed rhizomes in general: procyanidins B1 and B2, methyl derivatives of emodin bianthrone and emodin bianthrone-hexose, resveratrol-malonyl-hexoside and taxifolin derivatives. Characterization of flavan-3-ols and proanthocyanidins was facilitated by post-chromatographic derivatization of the corresponding chromatographic zones with 4-dimethylaminocinnamaldehyde (DMACA) detection reagent.
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Affiliation(s)
- Urška Jug
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia; Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1001 Ljubljana, Slovenia
| | - Irena Vovk
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
| | - Vesna Glavnik
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Damjan Makuc
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Katerina Naumoska
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
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Abstract
Plants produce specific structures constituting barriers, hindering the penetration of pathogens, while they also produce substances inhibiting pathogen growth. These compounds are secondary metabolites, such as phenolics, terpenoids, sesquiterpenoids, resins, tannins and alkaloids. Bioactive compounds are secondary metabolites from trees and shrubs and are used in medicine, herbal medicine and cosmetology. To date, fruits and flowers of exotic trees and shrubs have been primarily used as sources of bioactive compounds. In turn, the search for new sources of bioactive compounds is currently focused on native plant species due to their availability. The application of such raw materials needs to be based on knowledge of their chemical composition, particularly health-promoting or therapeutic compounds. Research conducted to date on European trees and shrubs has been scarce. This paper presents the results of literature studies conducted to systematise the knowledge on phenolic compounds found in trees and shrubs native to central Europe. The aim of this review is to provide available information on the subject and to indicate gaps in the present knowledge.
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Dabić Zagorac DČ, Fotirić Akšić MM, Glavnik V, Gašić UM, Vovk I, Tešić ŽL, Natić MM. Establishing the chromatographic fingerprints of flavan‐3‐ols and proanthocyanidins from rose hip (
Rosa
sp.) species. J Sep Sci 2020; 43:1431-1439. [DOI: 10.1002/jssc.201901271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/24/2020] [Accepted: 01/25/2020] [Indexed: 12/15/2022]
Affiliation(s)
| | | | - Vesna Glavnik
- Department of Food ChemistryNational Institute of Chemistry Ljubljana Slovenia
| | - Uroš M. Gašić
- Institute for Biological Research “Siniša Stanković” – National Institute of Republic of SerbiaUniversity of Belgrade Belgrade Serbia
| | - Irena Vovk
- Department of Food ChemistryNational Institute of Chemistry Ljubljana Slovenia
| | | | - Maja M. Natić
- Faculty of ChemistryUniversity of Belgrade Belgrade Serbia
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Bensa M, Glavnik V, Vovk I. Leaves of Invasive Plants-Japanese, Bohemian and Giant Knotweed-The Promising New Source of Flavan-3-ols and Proanthocyanidins. PLANTS 2020; 9:plants9010118. [PMID: 31963589 PMCID: PMC7020164 DOI: 10.3390/plants9010118] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/08/2020] [Accepted: 01/11/2020] [Indexed: 12/16/2022]
Abstract
This is the first report on identification of all B-type proanthocyanidins from monomers to decamers (monomers—flavan-3-ols, dimers, trimers, tetramers, pentamers, hexamers, heptamers, octamers, nonamers, and decamers) and some of their gallates in leaves of Japanese knotweed (Fallopia japonica Houtt.), giant knotweed (Fallopia sachalinensis F. Schmidt) and Bohemian knotweed (Fallopia × bohemica (Chrtek & Chrtkova) J.P. Bailey). Flavan-3-ols and proanthocyanidins were investigated using high performance thin-layer chromatography (HPTLC) coupled to densitometry, image analysis, and mass spectrometry (HPTLC–MS/MS). All species contained (−)-epicatechin and procyanidin B2, while (+)-catechin was only detected in Bohemian and giant knotweed. (−)-Epicatechin gallate, procyanidin B1 and procyanidin C1 was only confirmed in giant knotweed. Leaves of all three knotweeds have the same chemical profiles of proanthocyanidins with respect to the degree of polymerization but differ with respect to gallates. Therefore, chromatographic fingerprint profiles of proanthocyanidins enabled differentiation among leaves of studied knotweeds, and between Japanese knotweed leaves and rhizomes. Leaves of all three species proved to be a rich source of proanthocyanidins (based on the total peak areas), with the highest content in giant and the lowest in Japanese knotweed. The contents of monomers in Japanese, Bohemian and giant knotweed were 0.84 kg/t of dry weight (DW), 1.39 kg/t DW, 2.36 kg/t, respectively, while the contents of dimers were 0.99 kg/t DW, 1.40 kg/t, 2.06 kg/t, respectively. Giant knotweed leaves showed the highest variety of gallates (dimer gallates, dimer digallates, trimer gallates, tetramer gallates, pentamer gallates, and hexamer gallates), while only monomer gallates and dimer gallates were confirmed in Japanese knotweed and monomer gallates, dimer gallates, and dimer digallates were detected in leaves of Bohemian knotweed. The profile of the Bohemian knotweed clearly showed the traits inherited from Japanese and giant knotweed from which it originated.
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Affiliation(s)
- Maja Bensa
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia;
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Vesna Glavnik
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia;
- Correspondence: (V.G.); (I.V.); Tel.: +386-1476-0265 (V.G); +386-1476-0341 (I.V.)
| | - Irena Vovk
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia;
- Correspondence: (V.G.); (I.V.); Tel.: +386-1476-0265 (V.G); +386-1476-0341 (I.V.)
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Glavnik V, Vovk I. High performance thin-layer chromatography–mass spectrometry methods on diol stationary phase for the analyses of flavan-3-ols and proanthocyanidins in invasive Japanese knotweed. J Chromatogr A 2019; 1598:196-208. [DOI: 10.1016/j.chroma.2019.03.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 03/21/2019] [Accepted: 03/22/2019] [Indexed: 10/27/2022]
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12
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Jug U, Glavnik V, Kranjc E, Vovk I. HPTLC–densitometric and HPTLC–MS methods for analysis of flavonoids. J LIQ CHROMATOGR R T 2018. [DOI: 10.1080/10826076.2018.1448690] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Urška Jug
- Department of Food Chemistry, National Institute of Chemistry, Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Vesna Glavnik
- Department of Food Chemistry, National Institute of Chemistry, Ljubljana, Slovenia
| | - Eva Kranjc
- Department of Food Chemistry, National Institute of Chemistry, Ljubljana, Slovenia
| | - Irena Vovk
- Department of Food Chemistry, National Institute of Chemistry, Ljubljana, Slovenia
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Glavnik V, Vovk I, Albreht A. High performance thin-layer chromatography-mass spectrometry of Japanese knotweed flavan-3-ols and proanthocyanidins on silica gel plates. J Chromatogr A 2016; 1482:97-108. [PMID: 28034505 DOI: 10.1016/j.chroma.2016.12.059] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 12/25/2022]
Abstract
On-line elution based TLC-MS is now a well-established technique, but the quality of the data obtained can sometimes be hampered by a severe spectral background or by strong ion suppression, especially when silica gel plates are used in combination with an acidic modifier in the developing solvent. We solved this issue simply and efficiently using two pre-developments of the plates, firstly with methanol-formic acid (10:1, v/v) and secondly with acetonitrile-methanol (2:1, v/v). This solution resulted in significant improvement in the sensitivity of HPTLC-MS methods. The applicability of this approach was proven on analysis of flavan-3-ols and proanthocyanidins in crude extracts of Japanese knotweed (Fallopia japonica Houtt.) rhizomes. Separations on HPTLC silica gel and HPTLC silica gel MS grade plates using developing solvents toluene-acetone-formic acid (3:3:1, 6:6:1, 3:6:1, v/v) and dichloromethane-acetone-formic acid (1:1:0.1, v/v) were followed by post-chromatographic derivatization with 4-dimethylaminocinnamaldehyde (DMACA) detection reagent. Examination of the stability of the analytes on the start confirmed that the plates should be developed immediately after the application of standards and sample test solutions. In a five hours stability testing after development we discovered an unexpected phenomenon of enhanced absorption at 280nm. However, based on an experiment with post-chromatographic derivatization with DMACA detection reagent, the analytes were proven to be sufficiently stable in the time frame of an HPTLC-MS analysis. This was important for development of the first HPTLC-MS and HPTLC-MSn methods for identification of flavan-3-ols and B-type proanthocyanidins from monomers up to decamers. For the first time, based on this research methodology, trimers, trimer gallates, tetramer gallates, pentamers, pentamer gallates, hexamers, hexamer gallates, heptamers, octamers, nonamers and decamers were tentatively identified in Japanese knotweed rhizomes. Additionally, all developed HPTLC-MS methods have enabled simultaneous identification of stilbenes (resveratrol, piceatannol hexoside, piceid) and anthraquinones (emodin, emodin-O-hexoside, emodin-O-(acetyl)-hexoside and emodin-O-(6'-O-malonyl)-hexoside).
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Affiliation(s)
- Vesna Glavnik
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Irena Vovk
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia.
| | - Alen Albreht
- Department of Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
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Zhang QA, Fan XH, Zhang ZQ, Li T, Zhu CP, Zhang XR, Song W. Extraction, antioxidant capacity and identification of Semen Astragali Complanati (Astragalus complanatus R. Br.) phenolics. Food Chem 2013; 141:1295-300. [DOI: 10.1016/j.foodchem.2013.04.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 09/17/2012] [Accepted: 04/07/2013] [Indexed: 11/29/2022]
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15
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Smrke S, Vovk I. Comprehensive thin-layer chromatography mass spectrometry of flavanols from Juniperus communis L. and Punica granatum L. J Chromatogr A 2013; 1289:119-26. [DOI: 10.1016/j.chroma.2013.03.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 02/25/2013] [Accepted: 03/10/2013] [Indexed: 11/30/2022]
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16
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Muhammad I, Samoylenko V, Machumi F, Zaki MA, Mohammed R, Hetta MH, Gillum V. Preparation and Application of Reversed Phase Chromatorotor TM for the Isolation of Natural Products by Centrifugal Preparative Chromatography. Nat Prod Commun 2013. [DOI: 10.1177/1934578x1300800308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A method of preparation of rotors with a reversed phase (RP) solid silica gel sorbent layer has been developed for centrifugal preparative chromatography (CPC), also known as rotational planar chromatography (RPC). The rotors consist of binder free RP solid SiO2 layers of different thicknesses packed between two supported circular glass discs and can be used in any appropriate device for centrifugal chromatography, like Chromatotron® and CycloGraph®. Polar and /or semi-polar compounds with close R f values, as well as extracts and column fractions were separated and /or purified in a preparative and / or semi-preparative scale using the RP rotors, eluted with mixtures of aqueous-based solvents. We herein report three examples of its application, using RP ChromatorotorsTM, for the isolation of the diastereoisomeric alkaloids banistenosides I and II from Banisteriopsis caapi, saponins III and IV from Fagonia cretica, and the sesquiterpenes artemisinin (V) and artemisinic acid (VI) from Artemisia annua.
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Affiliation(s)
- Ilias Muhammad
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, The University of Mississippi, University, MS 38677, USA
| | - Volodymyr Samoylenko
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, The University of Mississippi, University, MS 38677, USA
| | - Francis Machumi
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, The University of Mississippi, University, MS 38677, USA
| | - Mohamed Ahmed Zaki
- National Center for Natural Products Research, School of Pharmacy, Research Institute of Pharmaceutical Sciences, The University of Mississippi, University, MS 38677, USA
- Department of Pharmacognosy, School of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Rabab Mohammed
- Department of Pharmacognosy, School of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Mona H. Hetta
- Department of Pharmacognosy, School of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Van Gillum
- American Scientific Glass Inc., 3252 Jean Drive, Memphis, TN 38118, USA
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Móricz Á, Kalász H. Centrifugal layer chromatography — Rotation planar chromatography. JPC-J PLANAR CHROMAT 2010. [DOI: 10.1556/jpc.23.2010.6.6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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18
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Densitometric determination of (+)-catechin and (−)-epicatechin by 4-dimethylaminocinnamaldehyde reagent. J Chromatogr A 2009; 1216:4485-91. [DOI: 10.1016/j.chroma.2009.03.026] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 03/06/2009] [Accepted: 03/10/2009] [Indexed: 11/18/2022]
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19
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Wang K, Liu Z, Huang JA, Fu D, Liu F, Gong Y, Wu X. TLC separation of catechins and theaflavins on polyamide plates. JPC-J PLANAR CHROMAT 2009. [DOI: 10.1556/jpc.22.2009.2.4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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20
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Almeida IF, Fernandes E, Lima JLFC, Costa PC, Bahia MF. Protective effect of Castanea sativa and Quercus robur leaf extracts against oxygen and nitrogen reactive species. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2008; 91:87-95. [PMID: 18337113 DOI: 10.1016/j.jphotobiol.2008.02.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 02/01/2008] [Accepted: 02/01/2008] [Indexed: 11/30/2022]
Abstract
Topical natural antioxidants are a useful strategy for the prevention of photoaging and oxidative stress mediated skin diseases. In view of this underlying principle, the screening of natural plant extracts with scavenging activity for pro-oxidant reactive species is a primary requirement for the development of new topical antioxidant formulations. In the present study, an ethanol:water (7:3) extract from Castanea sativa leaves and a ethanol:water (2:3) extract from Quercus robur leaves were evaluated for their putative in vitro scavenging effects on reactive oxygen species (ROS) namely superoxide radical (O(2)(-)), hydroxyl radical (HO()), peroxyl radical (ROO()), hydrogen peroxide (H(2)O(2)) and singlet oxygen ((1)O(2)) as well as on reactive nitrogen species (RNS) namely nitric oxide (()NO) and peroxynitrite (ONOO(-)). The extracts presented a high potency to scavenge the tested reactive species, all the IC(50)s being found at the microg/mL level. IC(50)s (mean+/-SE) for the ROS O(2)(-),HO(),H(2)O(2) and (1)O(2) were 13.6+/-1.8; 216+/-4; 410+/-8; 12.3+/-0.7 microug/mL, respectively, for C. sativa, and 11.0+/-0.5; 285+/-22; 251+/-32; 7.90+/-0.56 microg/mL, respectively, for Q. robur. The ORAC values obtained for ROO() were 1.24+/-0.13 for C. sativa and 1.09+/-0.06 for Q. robur. The IC(50)s (mean+/-SE) for ()NO and ONOO(-) were 3.10+/-0.14 and 1.49+/-0.10 microg/mL, respectively, for C. sativa and 3.13+/-0.11 and 0.95+/-0.02 microg/mL, respectively, for Q. robur. The content of total phenolics for C. sativa and Q. robur were 284+/-9 and 346+/-4 mg of gallic acid equivalents (GAE)/g of lyophilized extract respectively. The observed effects might be of relevance considering the putative interest of these extracts as topical antioxidants.
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Affiliation(s)
- Isabel F Almeida
- Departamento de Tecnologia Farmacêutica, Faculdade de Farmácia da, Universidade do Porto, Rua Aníbal Cunha 164, 4099-030 Porto, Portugal
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Almeida IF, Valentão P, Andrade PB, Seabra RM, Pereira TM, Amaral MH, Costa PC, Bahia MF. Oak leaf extract as topical antioxidant: free radical scavenging and iron chelating activities and in vivo skin irritation potential. Biofactors 2008; 33:267-79. [PMID: 19509462 DOI: 10.1002/biof.5520330403] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The topical application of antioxidants may be beneficial for the protection of the skin against UV damage. An extract of Quercus robur leaves was prepared and evaluated considering its putative application as topical antioxidant. The solvent and extractive method selection was monitored by 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging activity and polyphenols extraction (measured by the Folin Ciocalteu assay). Iron chelating activity and the phenolic composition (HPLC/DAD) were assessed on the extract obtained under optimized conditions. Skin irritation potential was investigated by performing an in vivo patch test in 19 volunteers. The extraction solvent which resulted in the highest activity was ethanol:water (4:6) and thus it was selected for further preparation of this extract. The IC50s for the iron chelation and DPPH scavenging assays were 153.8 +/- 26.3 microg x mL-1 and 7.53 +/- 0.71 microg x mL-1 (mean +/- SD), respectively. The total phenolic content was found to be 346.3 +/- 6.7 mg gallic acid equivalents (GAE)/g extract (mean +/- SD). Three phenolic compounds were identified in the extract namely: ellagic acid, rutin and hyperoside. The major identified component was ellagic acid. The patch test carried out showed that the extract can be regarded as safe for topical application.
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Affiliation(s)
- Isabel F Almeida
- Departamento de Tecnologia Farmacêutica, Faculdade de Farmácia da Universidade do Porto, Porto, Portugal
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Kalász H, Liktor‐Busa E, Janicsák G, Báthori M. Role of Preparative Rotation Planar Chromatography in the Isolation of Ecdysteroids. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070600759967] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Huba Kalász
- a Department of Pharmacology & Therapeutics, Faculty of Medicine and Health Sciences , United Arab Emirates University , Al Aim
| | - Erika Liktor‐Busa
- b Department of Pharmacognosy , University of Szeged , Szeged, Hungary
| | - Gábor Janicsák
- c Economical and Botanical Research Institute of the Hungarian Academy of Science , Vácrátót, Hungary
| | - Mária Báthori
- b Department of Pharmacognosy , University of Szeged , Szeged, Hungary
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Yrjönen T, Vovk I, Simonovska B, Mousa O, Hiltunen R, Vuorela H, Vuorela P. Comparison of Medium Pressure Solid–Liquid Extraction and Rotation Planar Extraction of Ficus Leaves with Reference to Optimum Operating Parameters. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120025524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Teijo Yrjönen
- a Division of Pharmacognosy, Department of Pharmacy , University of Helsinki , Helsinki, Finland
| | - Irena Vovk
- b Laboratory for Food Chemistry , National Institute of Chemistry , Ljubljana, Slovenia
| | - Breda Simonovska
- b Laboratory for Food Chemistry , National Institute of Chemistry , Ljubljana, Slovenia
| | - Ola Mousa
- a Division of Pharmacognosy, Department of Pharmacy , University of Helsinki , Helsinki, Finland
- c Faculty of Pharmacy, Department of Pharmacognosy , Cairo University , Giza, Egypt
| | - Raimo Hiltunen
- a Division of Pharmacognosy, Department of Pharmacy , University of Helsinki , Helsinki, Finland
| | - Heikki Vuorela
- a Division of Pharmacognosy, Department of Pharmacy , University of Helsinki , Helsinki, Finland
| | - Pia Vuorela
- d Department of Pharmacy, Viikki Drug Discovery Technology Center , University of Helsinki , P.O. Box 56 Viikinkaari 5E, Helsinki, FIN‐00014, Finland
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Salo P, Essén-Suuronen A, Salomies H, Ketola R, Kostiainen R. HPTLC, with UV and MS detection, and preparative-layer chromatography for analysis and purification of synthesis products. JPC-J PLANAR CHROMAT 2006. [DOI: 10.1556/jpc.19.2006.5.6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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25
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Vovk I, Simonovska B, Vuorela H. Separation of eight selected flavan-3-ols on cellulose thin-layer chromatographic plates. J Chromatogr A 2005; 1077:188-94. [PMID: 16001555 DOI: 10.1016/j.chroma.2005.03.096] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The potential of microcristaline cellulose as sorbent in the separation of eight compounds: (+)-catechin (C), (-)-epicatechin (EC), (-)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin gallate (EGCg), procyanidin B1 and procyanidin B2 was studied. Cellulose HPTLC plates prewashed in water (not necessary, when water was used as developing solvent) and dried with a hair dryer, bandwise application and development in horizontal developing chamber (sandwich configuration) gave the best results. Detection was performed using vanillin-H3PO4 reagent. Four new developing solvent systems were proposed: water, 1-propanol-water (20:80, v/v), 1-propanol-water-acetic acid (4:2:1, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v), and at least two of them were needed for the differentiation between all eight compounds. Surprisingly, water enabled the separation of epimers C from EC and GC from EGC, as well as the dimers procianidin B1 and B2. Additionally, C, EGC, B1 and B2 were separated from all the other compounds. The best choice for developing solvent is given for each of the studied compounds. The best separation of the five main catechins (EC, GC, EGC, ECg, EGCg) present in green tea extract was achieved using 1-propanol-water-acetic acid (20:80:1, v/v). The chromatograms of oak bark extract developed in solvents with higher water content (1-propanol-water (1:4, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v)) showed less bands than chromatograms developed in solvents with higher organic modifier content (e.g. 1-propanol-water-acetic acid (4:2:1, v/v)). It was proved that such behavior was due to the presence of procyanidins beside the main component catechin.
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Affiliation(s)
- Irena Vovk
- Laboratory for Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia.
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26
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Hompesch RW, Garcia CD, Weiss DJ, Vivanco JM, Henry CS. Analysis of natural flavonoids by microchip-micellar electrokinetic chromatography with pulsed amperometric detection. Analyst 2005; 130:694-700. [PMID: 15852139 DOI: 10.1039/b418368a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Catechins (catechin and other derivatives) are naturally occurring flavonoids present in a number of plants and foods. They are also part of numerous nutraceutical formulations because they are believed to have antioxidant, cancer chemo-preventative, anti-inflammatory and antimicrobial properties. The determination of catechins has traditionally been performed by HPLC. However, this methodology is both time and sample intensive and generates large amounts of organic solvent waste. In the current report, an application of MEKC using a PDMS microchip is presented for the analysis of catechins. The system uses pulsed amperometric detection for direct analysis of important naturally occurring catechins. The effect of pH, surfactant concentration, detection potential and signal stability were analyzed. Linear relationships were found between the concentration and peak current, with good stability and limits of detection of 8 [micro sign]M for catechin, epigallocatechin gallate and epicatechin, and 14 [micro sign]M for epicatechin gallate. Optimum conditions were applied to the detection of selected catechins in a commercially available green tea extract nutraceutical and the results were compared to HPLC analysis. The analysis using microchip micellar electrokinetic chromatography and pulsed amperometric detection was completed in 4.5 min, 10 times faster than the HPLC analysis.
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Affiliation(s)
- Richard W Hompesch
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
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Hofmann T, Albert L, Rétfalvi T. Quantitative TLC analysis of (+)-catechin and (−)-epicatechin fromFagus sylvaticaL. with and without red heartwood. JPC-J PLANAR CHROMAT 2004. [DOI: 10.1556/jpc.17.2004.5.5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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28
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Andrensek S, Simonovska B, Vovk I, Fyhrquist P, Vuorela H, Vuorela P. Antimicrobial and antioxidative enrichment of oak (Quercus robur) bark by rotation planar extraction using ExtraChrom. Int J Food Microbiol 2004; 92:181-7. [PMID: 15109795 DOI: 10.1016/j.ijfoodmicro.2003.09.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Revised: 09/15/2003] [Accepted: 09/16/2003] [Indexed: 11/25/2022]
Abstract
The multifunctional ExtraChrom instrument was used in the extraction of antimicrobial and radical scavenging components from oak (Quercus robur L.) bark. Milled and sieved oak bark was extracted with 80% (v/v) methanol solution in water on the ExtraChrom instrument using step-gradient in the preparative separation. Extracts were tested using agar diffusion method on Staphylococcus aureus, Enterobacter aerogenes and Candida albicans. Some extracts showed moderate bactericidal, fungicidal, bacteriostatic and fungistatic activity. The composition related to activity of the fractions and extracts was screened simultaneously by thin-layer chromatography (TLC) detected by UV and by spraying the plate with radical scavenging reagent 1,1-diphenyl-2-picrylhydrazyl (DPPH) to detect antioxidant activity. Thus, we could demonstrate the antiradical and antimicrobial activity of oak beneficial in the storage of wine against the oxidation and human microbial exposure.
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Affiliation(s)
- Samo Andrensek
- Laboratory for Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
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29
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Affiliation(s)
- Joseph Sherma
- Department of Chemistry, Lafayette College, Easton, Pennsylvania 18042, USA
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30
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Current awareness in phytochemical analysis. PHYTOCHEMICAL ANALYSIS : PCA 2003; 14:328-335. [PMID: 14627054 DOI: 10.1002/pca.680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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