Journal of Pharmaceutical and Biomedical Analysis, 2008
On the basis of the biological activities shown by yuccaols and gloriosaols from Yucca schidigera... more On the basis of the biological activities shown by yuccaols and gloriosaols from Yucca schidigera and Yucca gloriosa, the content of yuccaols and gloriosaols in two different parts of Y. gloriosa (roots and bark), was determined for each single compound, and compared with phenolic determination in Y. schidigera bark, concluding that Y. gloriosa bark and roots are rich sources of phenolic derivatives structurally related to resveratrol. LC/ESIMS (liquid chromatography coupled to electrospray mass spectrometry) qualitative and an LC/ESIMS/MS (liquid chromatography coupled to tandem electrospray mass spectrometry) quantitative studies of the phenolic fraction of Y. gloriosa were performed. LC/ESIMS/MS multiple reaction monitoring (MRM) method previously described for yuccaols in Y. schidigera was applied and optimised for separation and determination of gloriosaols and yuccaols in Y. gloriosa. Due to the sensitivity and the repeatability of the assay, we suggest this method as suitable for industrial quality control of raw materials and final products.
Journal of Pharmaceutical and Biomedical Analysis, 2010
The major phytochemical constituents, namely, alkaloids, flavonoids and ellagic acid derivatives,... more The major phytochemical constituents, namely, alkaloids, flavonoids and ellagic acid derivatives, of leaves of Camptotheca acuminata were identified using high performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry (ESI-MS) in extracts of plants cultivated in Italy and collected at different growth stages. Alkaloids related to camptothecin were identified and quantified by HPLC coupled with ESI-tandem mass spectrometry (MS/MS) employing, respectively, an ion trap and a triple quadrupole mass analyser. The fragmentation patterns of alkaloids related to camptothecin were analysed and a specific Multiple Reaction Monitoring HPLC-MS/MS method was developed for the quantitative determination of these constituents. The described method provides high sensitivity and specificity for the characterisation and quantitative determination of the alkaloids in C. acuminata.
Journal of Pharmaceutical and Biomedical Analysis, 2011
Acacia nilotica (L.) Del. syn is a species rich in polyphenolic constituents, in which catechins ... more Acacia nilotica (L.) Del. syn is a species rich in polyphenolic constituents, in which catechins are hypothesized to possess antioxidant properties and to play a role in the anti-inflammatory activity of several plants. Due to the complexity of catechin derivatives, the investigation of this class of natural compounds has been limited by difficulties in their separation. In this paper, rationalization of the phenolics occurring in the 80% EtOH extract of Acacia nilotica pods, on the basis of ESI-MS and ESI-MS/MS profiles, has been proposed. Additionally, an LC-ESI-MS qualitative study has been performed by using a C18 polar endcapped stationary phase. The fragmentation pattern obtained evidenced the presence in A. nilotica pods of galloylated catechin- and gallocatechin derivatives along with galloylated glucose derivatives. The structures were confirmed by NMR, after isolation of the pure compounds. In addition, the radical scavenging activities of extracts and pure compounds were investigated, by using the TEAC assay. Furthermore quantitative analyses were performed by LC-ESI-MS/MS, confirming the interest of this species as a rich source of very strong antioxidant principles.
Gloriosaols A (1) and B (2), two novel phenolic derivatives characterized by unusual spirostructu... more Gloriosaols A (1) and B (2), two novel phenolic derivatives characterized by unusual spirostructures made up of two C 15 units linked via a γ-lactone to a central stilbenic portion were isolated from the roots of Yucca gloriosa. On the basis of an extensive NMR analysis, the same basic ...
Journal of Pharmaceutical and Biomedical Analysis, 2006
Flavonoids and anthocyanins in berry extracts from Myrtus communis, prepared by following a typic... more Flavonoids and anthocyanins in berry extracts from Myrtus communis, prepared by following a typical Sardinia myrtle liqueur recipe, were identified by HPLC coupled with Electrospray Mass Spectrometry and quantified by HPLC coupled with Ultraviolet/Visible Detection in order to evaluate the stability of the extracts during 1 year of storage. Antioxidant activity was measured by using TEAC assay, and the free-radical scavenging activity was monitored during time of the stability evaluation. Anthocyanins have found to be the most instable compounds, but a considerable instability was observed also for flavonoids, suggesting the use of extracts not over 3 months from their preparation. The myrtle extract showed interesting free-radical scavenging activity. Antioxidant activity was preserved in 3 months.
A phytochemical analysis of the methanol extract of Tynanthus panurensis bark led to the isolatio... more A phytochemical analysis of the methanol extract of Tynanthus panurensis bark led to the isolation of one new phenylpropanoid glycoside, eugenol-O-[beta-D-xylopyranosyl-(1-->5)-O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside], the known verbascoside, isoverbascoside, and leucosceptoside, along with the known flavonoid apigenin 8-C-[beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside], namely, katchimoside. Their structures were established by NMR and ESIMS experiments. Additionally, a quantitative study of the phenylpropanoid glycosides fraction of T. panurensis bark and of the hydroalcoholic extract prepared according to the traditional recipe was performed by combining high-performance liquid chromatography diode array detection with positive electrospray ionization tandem mass spectrometry. The new eugenol derivate was found to be the most abundant phenylpropanoid glycoside in both dried bark (19.5 mg/g) and hydroalcoholic extract (0.24 mg/mL). The antioxidant activity of all the isolated compounds and of the methanol and hydroalcoholic extract of the bark was determined by measuring the free radical scavenging effects using the Trolox equivalent antioxidant capacity method. The traditional hydroalcoholic extract showed a moderate activity.
Two new phenolic constituents with unusual spirostructures, named yuccaols D (1) and E (2), were ... more Two new phenolic constituents with unusual spirostructures, named yuccaols D (1) and E (2), were isolated from the MeOH extract of Yucca schidigera bark. Their structures were established by spectroscopic (ESIMS and NMR) analysis. The new yuccaols D and E, along with resveratrol (3), trans-3,3',5,5'-tetrahydroxy-4'-methoxystilbene (4), yuccaols A-C (5-7), yuccaone A (8), larixinol (9), the MeOH extract of Yucca schidigera bark, and the phenolic portion of this extract, were assayed for antioxidant activity by measuring the free radical scavenging effects using two different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay). The significant activities exhibited by the phenolic fraction and its constituents in both tests show the potential use of Y. schidigera as a source of antioxidant principles.
Two new and one known furostanol saponins were isolated from the rhizomes of Yucca gloriosa. The ... more Two new and one known furostanol saponins were isolated from the rhizomes of Yucca gloriosa. The structures of the isolated compounds were established by detailed spectroscopic analysis (1D-, 2D NMR, ESI-MS, HR-MALDI-MS). The glycosidic profile of Y. gloriosa in ...
Journal of Pharmaceutical and Biomedical Analysis, 2008
On the basis of the biological activities shown by yuccaols and gloriosaols from Yucca schidigera... more On the basis of the biological activities shown by yuccaols and gloriosaols from Yucca schidigera and Yucca gloriosa, the content of yuccaols and gloriosaols in two different parts of Y. gloriosa (roots and bark), was determined for each single compound, and compared with phenolic determination in Y. schidigera bark, concluding that Y. gloriosa bark and roots are rich sources of phenolic derivatives structurally related to resveratrol. LC/ESIMS (liquid chromatography coupled to electrospray mass spectrometry) qualitative and an LC/ESIMS/MS (liquid chromatography coupled to tandem electrospray mass spectrometry) quantitative studies of the phenolic fraction of Y. gloriosa were performed. LC/ESIMS/MS multiple reaction monitoring (MRM) method previously described for yuccaols in Y. schidigera was applied and optimised for separation and determination of gloriosaols and yuccaols in Y. gloriosa. Due to the sensitivity and the repeatability of the assay, we suggest this method as suitable for industrial quality control of raw materials and final products.
Journal of Pharmaceutical and Biomedical Analysis, 2010
The major phytochemical constituents, namely, alkaloids, flavonoids and ellagic acid derivatives,... more The major phytochemical constituents, namely, alkaloids, flavonoids and ellagic acid derivatives, of leaves of Camptotheca acuminata were identified using high performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry (ESI-MS) in extracts of plants cultivated in Italy and collected at different growth stages. Alkaloids related to camptothecin were identified and quantified by HPLC coupled with ESI-tandem mass spectrometry (MS/MS) employing, respectively, an ion trap and a triple quadrupole mass analyser. The fragmentation patterns of alkaloids related to camptothecin were analysed and a specific Multiple Reaction Monitoring HPLC-MS/MS method was developed for the quantitative determination of these constituents. The described method provides high sensitivity and specificity for the characterisation and quantitative determination of the alkaloids in C. acuminata.
Journal of Pharmaceutical and Biomedical Analysis, 2011
Acacia nilotica (L.) Del. syn is a species rich in polyphenolic constituents, in which catechins ... more Acacia nilotica (L.) Del. syn is a species rich in polyphenolic constituents, in which catechins are hypothesized to possess antioxidant properties and to play a role in the anti-inflammatory activity of several plants. Due to the complexity of catechin derivatives, the investigation of this class of natural compounds has been limited by difficulties in their separation. In this paper, rationalization of the phenolics occurring in the 80% EtOH extract of Acacia nilotica pods, on the basis of ESI-MS and ESI-MS/MS profiles, has been proposed. Additionally, an LC-ESI-MS qualitative study has been performed by using a C18 polar endcapped stationary phase. The fragmentation pattern obtained evidenced the presence in A. nilotica pods of galloylated catechin- and gallocatechin derivatives along with galloylated glucose derivatives. The structures were confirmed by NMR, after isolation of the pure compounds. In addition, the radical scavenging activities of extracts and pure compounds were investigated, by using the TEAC assay. Furthermore quantitative analyses were performed by LC-ESI-MS/MS, confirming the interest of this species as a rich source of very strong antioxidant principles.
Gloriosaols A (1) and B (2), two novel phenolic derivatives characterized by unusual spirostructu... more Gloriosaols A (1) and B (2), two novel phenolic derivatives characterized by unusual spirostructures made up of two C 15 units linked via a γ-lactone to a central stilbenic portion were isolated from the roots of Yucca gloriosa. On the basis of an extensive NMR analysis, the same basic ...
Journal of Pharmaceutical and Biomedical Analysis, 2006
Flavonoids and anthocyanins in berry extracts from Myrtus communis, prepared by following a typic... more Flavonoids and anthocyanins in berry extracts from Myrtus communis, prepared by following a typical Sardinia myrtle liqueur recipe, were identified by HPLC coupled with Electrospray Mass Spectrometry and quantified by HPLC coupled with Ultraviolet/Visible Detection in order to evaluate the stability of the extracts during 1 year of storage. Antioxidant activity was measured by using TEAC assay, and the free-radical scavenging activity was monitored during time of the stability evaluation. Anthocyanins have found to be the most instable compounds, but a considerable instability was observed also for flavonoids, suggesting the use of extracts not over 3 months from their preparation. The myrtle extract showed interesting free-radical scavenging activity. Antioxidant activity was preserved in 3 months.
A phytochemical analysis of the methanol extract of Tynanthus panurensis bark led to the isolatio... more A phytochemical analysis of the methanol extract of Tynanthus panurensis bark led to the isolation of one new phenylpropanoid glycoside, eugenol-O-[beta-D-xylopyranosyl-(1-->5)-O-beta-D-apiofuranosyl-(1-->6)-O-beta-D-glucopyranoside], the known verbascoside, isoverbascoside, and leucosceptoside, along with the known flavonoid apigenin 8-C-[beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside], namely, katchimoside. Their structures were established by NMR and ESIMS experiments. Additionally, a quantitative study of the phenylpropanoid glycosides fraction of T. panurensis bark and of the hydroalcoholic extract prepared according to the traditional recipe was performed by combining high-performance liquid chromatography diode array detection with positive electrospray ionization tandem mass spectrometry. The new eugenol derivate was found to be the most abundant phenylpropanoid glycoside in both dried bark (19.5 mg/g) and hydroalcoholic extract (0.24 mg/mL). The antioxidant activity of all the isolated compounds and of the methanol and hydroalcoholic extract of the bark was determined by measuring the free radical scavenging effects using the Trolox equivalent antioxidant capacity method. The traditional hydroalcoholic extract showed a moderate activity.
Two new phenolic constituents with unusual spirostructures, named yuccaols D (1) and E (2), were ... more Two new phenolic constituents with unusual spirostructures, named yuccaols D (1) and E (2), were isolated from the MeOH extract of Yucca schidigera bark. Their structures were established by spectroscopic (ESIMS and NMR) analysis. The new yuccaols D and E, along with resveratrol (3), trans-3,3',5,5'-tetrahydroxy-4'-methoxystilbene (4), yuccaols A-C (5-7), yuccaone A (8), larixinol (9), the MeOH extract of Yucca schidigera bark, and the phenolic portion of this extract, were assayed for antioxidant activity by measuring the free radical scavenging effects using two different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay). The significant activities exhibited by the phenolic fraction and its constituents in both tests show the potential use of Y. schidigera as a source of antioxidant principles.
Two new and one known furostanol saponins were isolated from the rhizomes of Yucca gloriosa. The ... more Two new and one known furostanol saponins were isolated from the rhizomes of Yucca gloriosa. The structures of the isolated compounds were established by detailed spectroscopic analysis (1D-, 2D NMR, ESI-MS, HR-MALDI-MS). The glycosidic profile of Y. gloriosa in ...
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