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Monika A Olszewska - One of the best experts on this subject based on the ideXlab platform.
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contribution of individual polyphenols to antioxidant activity of Cotoneaster bullatus and Cotoneaster zabelii leaves structural relationships synergy effects and application for quality control
2020Co-Authors: Agnieszka Kicel, Aleksandra Owczarek, Paulina Kapusta, Joanna Kolodziejczykczepas, Monika A OlszewskaAbstract:Cotoneaster plants are sources of traditional medicines and dietary products, with health benefits resulting from their phenolic contents and antioxidant activity. In this work, active markers of the leaves of C. bullatus and C. zabelii were characterized and evaluated in an integrated phytochemical and biological activity study. Based on UHPLC-PDA-ESI-MS3 analysis, twelve analytes were preselected from the constituents of the hydromethanolic leaf extracts, and two of them—caffeoylmalic acid and quercetin 3--O-β-d-(2″--O-β-d-xylopyranosyl)galactopyranoside (QPH)—were isolated for full identification (NMR spectroscopy: 1H, 13C, COSY, HMBC, HMQC). All selected phenolics contributed to the antioxidant activity of the extracts, which was demonstrated in chemical in vitro tests (DPPH, FRAP, and TBARS) and in a biological model of human plasma exposed to oxidative/nitrative stress induced by peroxynitrite. This contribution was partly due to the synergy between individual polyphenols, evidenced by an isobolographic analysis of the interactions of (–)-epicatechin, chlorogenic acid, and QPH as representatives of three classes of Cotoneaster polyphenols. All twelve markers, including also neochlorogenic acid, cryptochlorogenic acid, procyanidin B2, procyanidin C1, rutin, hyperoside, isoquercitrin, and quercitrin, were thus applied as calibration standards, and a fast, accurate, reproducible, and fully validated RP-HPLC-PDA method for quality control and standardization of the target extracts was proposed.
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multifunctional phytocompounds in Cotoneaster fruits phytochemical profiling cellular safety anti inflammatory and antioxidant effects in chemical and human plasma models in vitro
2018Co-Authors: Agnieszka Kicel, Aleksandra Owczarek, Joanna Kolodziejczykczepas, Magdalena Rutkowska, Anna Wajsbonikowska, Sebastian Granica, Pawel Nowak, Monika A OlszewskaAbstract:The work presents the results of an investigation into the molecular background of the activity of Cotoneaster fruits, providing a detailed description of their phytochemical composition and some of the mechanisms of their anti-inflammatory and antioxidant effects. GS-FID-MS and UHPLC-PDA-ESI-MS3 methods were applied to identify the potentially health-beneficial constituents of lipophilic and hydrophilic fractions, leading to the identification of fourteen unsaturated fatty acids (with dominant linoleic acid, 375.4–1690.2 mg/100 g dw), three phytosterols (with dominant β-sitosterol, 132.2–463.3 mg/100 g), two triterpenoid acids (10.9–54.5 mg/100 g), and twenty-six polyphenols (26.0–43.5 mg GAE/g dw). The most promising polyphenolic fractions exhibited dose-dependent anti-inflammatory activity in in vitro tests of lipoxygenase (IC50 in the range of 7.7–24.9 μg/U) and hyaluronidase (IC50 in the range of 16.4–29.3 μg/U) inhibition. They were also demonstrated to be a source of effective antioxidants, both in in vitro chemical tests (DPPH, FRAP, and TBARS) and in a biological model, in which at in vivo-relevant levels (1–5 μg/mL) they normalized/enhanced the nonenzymatic antioxidant capacity of human plasma and efficiently protected protein and lipid components of plasma against peroxynitrite-induced oxidative/nitrative damage. Moreover, the investigated extracts did not exhibit cytotoxicity towards human PMBCs. Among the nine Cotoneaster species tested, C. hjelmqvistii, C. zabelii, C. splendens, and C. bullatus possess the highest bioactive potential and might be recommended as dietary and functional food products.
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phenolic profile and antioxidant potential of leaves from selected Cotoneaster medik species
2016Co-Authors: Agnieszka Kicel, Piotr Michel, Aleksandra Owczarek, Anna Marchelak, Dorota żyzelewicz, Grazyna Budryn, Joanna Oracz, Monika A OlszewskaAbstract:The antioxidant efficiency of 70% aqueous methanolic extracts from the leaves of twelve selected Cotoneaster Medik. species was evaluated using four complementary in vitro tests based on SET- (single electron transfer) and HAT-type (hydrogen atom transfer) mechanisms (DPPH, FRAP, O2•− and H2O2 scavenging assays). The samples exhibited the dose-dependent responses in all assays with activity parameters of EC50 = 18.5–34.5 µg/mL for DPPH; 0.9–3.8 mmol Fe2+/g for FRAP; SC50 = 27.7–74.8 µg/mL for O2•−; and SC50 = 29.0–91.3 µg/mL for H2O2. Significant linear correlations (|r| = 0.76–0.97, p < 0.01) between activity parameters and total contents of phenolics (5.2%–15.4% GAE) and proanthocyanidins (2.1%–15.0% CYE), with weak or no effects for chlorogenic acid isomers (0.69%–2.93%) and total flavonoids (0.28%–1.40%) suggested that among the listed polyphenols, proanthocyanidins are the most important determinants of the tested activity. UHPLC-PDA-ESI-QTOF-MS analyses led to detection of 34 polyphenols, of which 10 B-type procyanidins, 5 caffeoylquinic acids and 14 flavonoids were identified. After cluster analysis of the data matrix, the leaves of Cotoneaster zabelii, C. splendens, C. bullatus, C. divaricatus, C. hjelmqvistii and C. lucidus were selected as the most promising sources of natural antioxidants, exhibiting the highest phenolic levels and antioxidant capacities, and therefore the greatest potential for pharmaceutical applications.
Agnieszka Kicel - One of the best experts on this subject based on the ideXlab platform.
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an overview of the genus Cotoneaster rosaceae phytochemistry biological activity and toxicology
2020Co-Authors: Agnieszka KicelAbstract:Traditional herbal medicines have become a subject of global importance with both medical and economic implications. The regular consumption of herbal drugs has led to serious concerns regarding their quality, effectiveness, and safety. Thus, relevant scientific evidence has become an important criterion for the acceptance of traditional health claims. The genus Cotoneaster Medikus provides numerous species traditionally used in Asian medicine for the treatment of haemorrhoids, diabetes, and cardiovascular diseases. This review summarises the achievements of modern research on the Cotoneaster taxa, including ethnobotany, phytochemistry, pharmacology, and toxicology. To date, more than 90 compounds have been isolated or analytically identified in Cotoneaster leaves, fruits, flowers or twigs. These phytochemicals are categorised into flavonoids, procyanidins, phenolic acids, cotonefurans, cyanogenic glycosides, triterpenes, sterols, fatty acids, volatile compounds, and carbohydrates, and many of them are responsible for Cotoneaster pharmacological properties including antioxidant, anti-inflammatory, antimicrobial, antiparasitic, hepatoprotective, anti-diabetic or anti-dyslipidaemic activity. In order to ensure the safety of pharmaceutical applications, the potential toxicity of Cotoneaster extracts has also been investigated. In conclusion, this systematic review provides an important reference base for further study into the various medical applications of both the dry extracts and pure isolates of Cotoneaster species.
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contribution of individual polyphenols to antioxidant activity of Cotoneaster bullatus and Cotoneaster zabelii leaves structural relationships synergy effects and application for quality control
2020Co-Authors: Agnieszka Kicel, Aleksandra Owczarek, Paulina Kapusta, Joanna Kolodziejczykczepas, Monika A OlszewskaAbstract:Cotoneaster plants are sources of traditional medicines and dietary products, with health benefits resulting from their phenolic contents and antioxidant activity. In this work, active markers of the leaves of C. bullatus and C. zabelii were characterized and evaluated in an integrated phytochemical and biological activity study. Based on UHPLC-PDA-ESI-MS3 analysis, twelve analytes were preselected from the constituents of the hydromethanolic leaf extracts, and two of them—caffeoylmalic acid and quercetin 3--O-β-d-(2″--O-β-d-xylopyranosyl)galactopyranoside (QPH)—were isolated for full identification (NMR spectroscopy: 1H, 13C, COSY, HMBC, HMQC). All selected phenolics contributed to the antioxidant activity of the extracts, which was demonstrated in chemical in vitro tests (DPPH, FRAP, and TBARS) and in a biological model of human plasma exposed to oxidative/nitrative stress induced by peroxynitrite. This contribution was partly due to the synergy between individual polyphenols, evidenced by an isobolographic analysis of the interactions of (–)-epicatechin, chlorogenic acid, and QPH as representatives of three classes of Cotoneaster polyphenols. All twelve markers, including also neochlorogenic acid, cryptochlorogenic acid, procyanidin B2, procyanidin C1, rutin, hyperoside, isoquercitrin, and quercitrin, were thus applied as calibration standards, and a fast, accurate, reproducible, and fully validated RP-HPLC-PDA method for quality control and standardization of the target extracts was proposed.
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multifunctional phytocompounds in Cotoneaster fruits phytochemical profiling cellular safety anti inflammatory and antioxidant effects in chemical and human plasma models in vitro
2018Co-Authors: Agnieszka Kicel, Aleksandra Owczarek, Joanna Kolodziejczykczepas, Magdalena Rutkowska, Anna Wajsbonikowska, Sebastian Granica, Pawel Nowak, Monika A OlszewskaAbstract:The work presents the results of an investigation into the molecular background of the activity of Cotoneaster fruits, providing a detailed description of their phytochemical composition and some of the mechanisms of their anti-inflammatory and antioxidant effects. GS-FID-MS and UHPLC-PDA-ESI-MS3 methods were applied to identify the potentially health-beneficial constituents of lipophilic and hydrophilic fractions, leading to the identification of fourteen unsaturated fatty acids (with dominant linoleic acid, 375.4–1690.2 mg/100 g dw), three phytosterols (with dominant β-sitosterol, 132.2–463.3 mg/100 g), two triterpenoid acids (10.9–54.5 mg/100 g), and twenty-six polyphenols (26.0–43.5 mg GAE/g dw). The most promising polyphenolic fractions exhibited dose-dependent anti-inflammatory activity in in vitro tests of lipoxygenase (IC50 in the range of 7.7–24.9 μg/U) and hyaluronidase (IC50 in the range of 16.4–29.3 μg/U) inhibition. They were also demonstrated to be a source of effective antioxidants, both in in vitro chemical tests (DPPH, FRAP, and TBARS) and in a biological model, in which at in vivo-relevant levels (1–5 μg/mL) they normalized/enhanced the nonenzymatic antioxidant capacity of human plasma and efficiently protected protein and lipid components of plasma against peroxynitrite-induced oxidative/nitrative damage. Moreover, the investigated extracts did not exhibit cytotoxicity towards human PMBCs. Among the nine Cotoneaster species tested, C. hjelmqvistii, C. zabelii, C. splendens, and C. bullatus possess the highest bioactive potential and might be recommended as dietary and functional food products.
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phenolic profile and antioxidant potential of leaves from selected Cotoneaster medik species
2016Co-Authors: Agnieszka Kicel, Piotr Michel, Aleksandra Owczarek, Anna Marchelak, Dorota żyzelewicz, Grazyna Budryn, Joanna Oracz, Monika A OlszewskaAbstract:The antioxidant efficiency of 70% aqueous methanolic extracts from the leaves of twelve selected Cotoneaster Medik. species was evaluated using four complementary in vitro tests based on SET- (single electron transfer) and HAT-type (hydrogen atom transfer) mechanisms (DPPH, FRAP, O2•− and H2O2 scavenging assays). The samples exhibited the dose-dependent responses in all assays with activity parameters of EC50 = 18.5–34.5 µg/mL for DPPH; 0.9–3.8 mmol Fe2+/g for FRAP; SC50 = 27.7–74.8 µg/mL for O2•−; and SC50 = 29.0–91.3 µg/mL for H2O2. Significant linear correlations (|r| = 0.76–0.97, p < 0.01) between activity parameters and total contents of phenolics (5.2%–15.4% GAE) and proanthocyanidins (2.1%–15.0% CYE), with weak or no effects for chlorogenic acid isomers (0.69%–2.93%) and total flavonoids (0.28%–1.40%) suggested that among the listed polyphenols, proanthocyanidins are the most important determinants of the tested activity. UHPLC-PDA-ESI-QTOF-MS analyses led to detection of 34 polyphenols, of which 10 B-type procyanidins, 5 caffeoylquinic acids and 14 flavonoids were identified. After cluster analysis of the data matrix, the leaves of Cotoneaster zabelii, C. splendens, C. bullatus, C. divaricatus, C. hjelmqvistii and C. lucidus were selected as the most promising sources of natural antioxidants, exhibiting the highest phenolic levels and antioxidant capacities, and therefore the greatest potential for pharmaceutical applications.
Hong Xiao-yue - One of the best experts on this subject based on the ideXlab platform.
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FIGURE 10 in Seven new species of Phyllocoptini from Tibet Autonomous Region, China (Acari: Eriophyidae: Phyllocoptinae)
2018Co-Authors: Song Zi-wei, Xue Xiao-feng, Hong Xiao-yueAbstract:FIGURE 10. Calepitrimerus Cotoneaster sp. nov. L, lateral view of female; em, empodium; LO, enlarged lateral view of opisthosoma
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FIGURE 9 in Seven new species of Phyllocoptini from Tibet Autonomous Region, China (Acari: Eriophyidae: Phyllocoptinae)
2018Co-Authors: Song Zi-wei, Xue Xiao-feng, Hong Xiao-yueAbstract:FIGURE 9. Calepitrimerus Cotoneaster sp. nov. D, dorsal view of female; CG, coxae and external genitalia of female; L 1, leg I; L 2, leg II
Aymerich Pere - One of the best experts on this subject based on the ideXlab platform.
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Contribució al coneixement de la flora al·lòctona del nord i el centre de Catalunya
2021Co-Authors: Aymerich PereAbstract:Presentem dades florístiques recents sobre plantes al·lòctones rares observades com a casuals o naturalitzades, sobretot escapades de jardins. Segons la informació consultada, són citades per primera vegada a la península Ibèrica: Euphorbia glyptosperma Engelm. (naturalitzada), Clerodendrum bungei Steud., Clerodendrum trichotomum Thunb., Cotoneaster divaricatus Rehder & E. H. Wilson i Opuntia scheeri F.A.C. Weber (casuals). Són novetats per a Catalunya: Helianthus × laetiflorus Pers. (naturalitzada), Achillea ptarmica L., Tradescantia pallida (Rose) D. R. Hunt i Tradescantia zebrina Bosse (casuals). Confirmem també la presència actual de poblacions d'Atriplex tatarica L., espècie que havia estat considerada dubtosa a la península Ibèrica.We provide floristic data about some rare alien plants in Catalonia, mainly garden escapes. According to the available information, these species are reported for the first time in the Iberian Peninsula: Euphorbia glyptosperma Engelm. (naturalised), Clerodendrum bungei Steud., Clerodendrum trichotomum Thunb., Cotoneaster divaricatus Rehder & E. H. Wilson and Opuntia scheeri F.A.C. Weber (casuals). These species were previously reported for the Iberian Peninsula but are new taxa for the Catalan flora: Helianthus × laetiflorus Pers. (naturalitsed), Achillea ptarmica L., Tradescantia pallida (Rose) D.R. Hunt and Tradescantia zebrina Bosse (casuals). We also confirm the presence of Atriplex tatarica L., a species sometimes considered doubtful for the Iberian flora
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Contribution to the knowledge of the alien flora in northern and central Catalonia (NE Iberian Peninsula)
2016Co-Authors: Aymerich PereAbstract:Presentem dades florístiques recents sobre plantes al·lòctones rares observades com a casuals o naturalitzades, sobretot escapades de jardins. Segons la informació consultada, són citades per primera vegada a la península Ibèrica: Euphorbia glyptosperma Engelm. (naturalitzada), Clerodendrum bungei Steud., Clerodendrum trichotomum Thunb., Cotoneaster divaricatus Rehder & E. H. Wilson i Opuntia scheeri F.A.C. Weber (casuals). Són novetats per a Catalunya: Helianthus × laetiflorus Pers. (naturalitzada), Achillea ptarmica L., Tradescantia pallida (Rose) D. R. Hunt i Tradescantia zebrina Bosse (casuals). Confirmem també la presència actual de poblacions d’Atriplex tatarica L., espècie que havia estat considerada dubtosa a la península Ibèrica.We provide floristic data about some rare alien plants in Catalonia, mainly garden escapes. According to the available information, these species are reported for the first time in the Iberian Peninsula: Euphorbia glyptosperma Engelm. (naturalised), Clerodendrum bungei Steud., Clerodendrum trichotomum Thunb., Cotoneaster divaricatus Rehder & E. H. Wilson and Opuntia scheeri F.A.C. Weber (casuals). These species were previously reportedfor the Iberian Peninsula but are new taxa for the Catalan flora: Helianthus × laetiflorus Pers. (naturalitsed), Achillea ptarmica L., Tradescantia pallida (Rose) D.R. Hunt and Tradescantia zebrina Bosse (casuals). We also confirm the presence of Atriplex tatarica L., a species sometimes considered doubtful for the Iberian flora
Galasso Gabriele - One of the best experts on this subject based on the ideXlab platform.
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Notulae to the Italian alien vascular flora: 7
2019Co-Authors: Galasso Gabriele, Domina Gianniantonio, Brundu Giuseppe, Ardenghi, Nicola M. G., Aristarchi Claudio, Bacchetta Gianluigi, Bartolucci Fabrizio, Bonari Gianmaria, Bouvet Daniela, Buono SergioAbstract:In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, and status changes for Italy or for Italian administrative regions of taxa in the genera Abies, Actinidia, Alooe, Amaryllis, Anredera, Arctotheca, Bidens, Cardiospermum, Celosia, Commelina, Cotoneaster, Cyclamen, Eclipta, Euphorbia, Grevillea, Hedera, Hibiscus, Impatiens, Juglans, Kalanchoe, Koelreuteria, Lindernia, Melinis, Myriophyllum, Nandina, Nicotiana, Oenothera, Oxalis, Parthenocissus, Phoenix, Phyllanthus, Physalis, Plumbago, Pteris, Quercus, Setaria, Symphytum, Tagetes, and Washingtonia. Nomenclatural and distribution updates, published elsewhere are provided as Suppl. material 1
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Notulae to the Italian alien vascular flora. I
2016Co-Authors: Galasso Gabriele, Domina Gianniantonio, Adorni Michele, Ardenghi, Nicola Maria Giuseppe, Banfi Enrico, Bedini Gianni, Bertolli Alessio, Brundu Giuseppe, Calbi Mario, Cecchi LorenzoAbstract:In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions, and confirmations for Italy or for Italian administrative regions for taxa in the genera Agave, Arctotheca, Berberis, Bidens, Cardamine, Catalpa, Cordyline, Cotoneaster, Dichondra, Elaeagnus, Eragrostis, Impatiens, Iris, Koelreuteria, Lamiastrum, Lantana, Ligustrum, Limnophila, Lonicera, Lycianthes, Maclura, Mazus, Paspalum, Pelargonium, Phyllanthus, Pyracantha, Ruellia, Sorghum, Symphyotrichum, Triticum, Tulbaghia and Youngia
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Notulae to the Italian alien vascular flora: 2
2016Co-Authors: Galasso Gabriele, Domina Gianniantonio, Ardenghi, Nicola Maria Giuseppe, Banfi Enrico, Bartolucci Fabrizio, Bonari Gianmaria, Arrigoni Pierfranco, Buccomino Giovanni, Ciaschetti Giampiero, Conti FabioAbstract:In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions and confirmations for Italy or for Italian administrative regions for taxa in the genera Ageratum, Aster, Buddleja, Cedrus, Centranthus, Cephalotaxus, Clerodendrum, Cotoneaster, Cyperus, Honorius, Lantana, Ligustrum, Morus, Muscari, Oenothera, Opuntia, Platycladus, Plumbago, Pseudotsuga, Sedum, Sporobolus, Stachys, Ulmus and Yucca. A nomen novum, Stachys talbotii, is proposed as a replacement name for Sideritis purpurea
