Analysis of the methanol-soluble resin glycosides from the roots of Operculina macrocarpa was ass... more Analysis of the methanol-soluble resin glycosides from the roots of Operculina macrocarpa was assessed by generating NMR profiles of five glycosidic acids obtained through saponification, acetylation, and recycling HPLC purification. Operculinic acid H (1), two novel hexasaccharides, operculinic acids I (2) and J (3), the known purgic acid A (4), and a quinovopyranoside of (-)-(7 R)-hydroxydecanoic acid, operculinic acid K (5), were isolated. Three intact resin glycosides related to 1, the novel macrocarposidic acids A (6) and B (7), in addition to the previously known macrocarposidic acid C (8), were also purified with isovaleroyl, tigloyl, and exogonoyl [(3 S,9 R)-3,6:6,9-diepoxydecanoyl] groups as esterifying residues. A selective intramolecular lactonization was produced to generate a macrocyclic artifact (17) during acetylation of 1, resembling the distinctive structure of the Convolvulaceous resin glycosides.
Hyptis monticola Mart. ex Benth. (Lamiaceae) is an endemic species of altitude regions of Brazil.... more Hyptis monticola Mart. ex Benth. (Lamiaceae) is an endemic species of altitude regions of Brazil. From the leaves of this plant, two 5,6-dihydro-α-pyrones, named monticolides A and B, have been reported as cytotoxic agents against different tumor cell lines. The isolation by high-speed countercurrent chromatography in combination with recycling preparative high-performance liquid chromatography of the undescribed monticolides C-F is presented. These compounds corresponded to a series of related monticolide derivatives differing from each other by the number of acyl substituents. Their characterization by mass spectrometry and nuclear magnetic resonance is also presented, in conjunction with an evidence by a simple chemical correlation for their absolute stereochemistry. The distribution of these chemical markers in extracts of flowers, leaves and branches collected in different seasons by electrospray ionization ion trap mass spectrometry in positive mode was analyzed. Multivariate data analyses indicated that seasonality affects monticolide concentrations in different organs of the aerial parts. Monticolides A-F seem to be present as the original markers of the analyzed plant. However, mono-, di- and triacetylated monticolides can undergo acid-catalyzed transesterifications and their natural yields estimated were affected during the isolation procedures.
Os Yorubás formam um dos maiores grupos étnico-linguísticos da África Ocidental. A Medicina Tradi... more Os Yorubás formam um dos maiores grupos étnico-linguísticos da África Ocidental. A Medicina Tradicional Africana praticada pelos Yorubá inclui uma série de práticas empregadas nos serviços de cuidados gerais de saúde. Com a vinda forçada à América a partir da colonização portuguesa, estes povos trouxeram seus rituais e sua visão de medicina para o Brasil, originando a religião conhecida como Candomblé. O ponto de partida do presente trabalho foi realizar um estudo de revisão sobre a Medicina Tradicional empregada pelos povos africanos de etnia Yorubá na África, traçando um paralelo com seus descendentes praticantes do Candomblé, no Brasil, em uma perspectiva epistemológica, refletindo sobre história, ciências e saúde destes povos, e os desafios à sua consolidação como sistema médico tradicional.
Stingless bee honey (SBH) is gaining attention due to its nutritional, sensorial, and medicinal c... more Stingless bee honey (SBH) is gaining attention due to its nutritional, sensorial, and medicinal characteristics. This study focuses on the combination of physicochemical properties, antioxidant capacity, mineral profile, and mass spectrometry-based fingerprints, using a chemometric approach to differentiate SBH (n = 18) from three different Brazilian biogeographical zones (Caatinga, Cerrado, and Atlantic Forest). The physicochemical properties of SBH varied, resulting in a wide range of water activity, moisture, total soluble solids, pH, and total and free acidity. The Caatinga honey showed the highest and the lowest contents of phenolics and flavonoids, respectively. The antioxidant free-radical scavenging assays demonstrated that the Brazilian SBH has a high antioxidant potential. The mineral profile of honey samples from the Atlantic Forest revealed higher contents of Ca and Fe while the Cerrado and Caatinga honey showed the highest P contents. Partial Least-Squares Discriminant ...
ETHNOPHARMACOLOGICAL RELEVANCE Siparuna species are used in Brazilian Folk Medicine for the treat... more ETHNOPHARMACOLOGICAL RELEVANCE Siparuna species are used in Brazilian Folk Medicine for the treatment and prophylaxis of colds, fever, headache, gastrointestinal disorders and rheumatic pain. AIM OF THE STUDY This study aimed to investigate a possible anti-influenza activity of 25 extracts from leaves of Amazonian S. cristata, S. decipiens, S. glycycarpa, S. reginae and S. sarmentosa based on their folk medicinal uses as well as to investigate their metabolic fingerprinting. The chemical composition of the active extracts was further dereplicated. MATERIAL AND METHODS The chemical composition of the crude EtOH extracts from five Siparuna species were investigated by ESI (±) LC-QTOF-MS2. Organic extracts were obtained by liquid-liquid partition with solvents of increasing polarity, generating 25 extracts which were subjected to a quick DI-ESI (±) IT-MS fingerprint analysis. These extracts were tested against influenza virus replication and cellular toxicity using MDCK cells and influenza A/Michigan/45/2015 (H1N1)pdm09 virus. The compounds in the active BuOH extracts from S. glycycarpa and S. sarmentosa were annotated by ESI (±) LC-QTOF-MS2. RESULTS Analysis of the EtOH extracts revealed the presence of alkaloids and flavonoids, in the positive and negative ionization modes. Out of the 25 organic extracts screened for their antiviral activity, the BuOH extracts from S. glycycarpa and S. sarmentosa were the most active, inhibiting 96.0 ± 1.3 % and 89.5 ± 0.8 % of influenza virus replication 24 h post-infection. These inhibitory effects were manteined until 72hpi. Alkaloids, O- and C-flavonoid glycosides, dihydrochalcones and a procyanidin dimer were annotated in these extracts. CONCLUSIONS The inhibitory effect against influenza A(H1N1)pdm09 virus replication shown by Amazonian Siparuna species corroborates the use of these plants in Brazilian Folk Medicine, showing their potential as anti-influenza agents. These promising results stimulate the continuation of this study with the aim of isolating the compound(s) responsible for this bioactivity, thus contributing to a better knowledge of those species and to the research of natural products with potential anti-influenza activity.
ETHNOPHARMACOLOGICAL RELEVANCE In Latin American Traditional Medicine, the use of Burseraceae ole... more ETHNOPHARMACOLOGICAL RELEVANCE In Latin American Traditional Medicine, the use of Burseraceae oleoresins for headache relief is widespread. In the quilombola (maroon) communities of the municipality of Oriximiná, Pará State, Brazil, Burseraceae oleoresins are burned as incenses to treat headache; an effect attained by inhaling the smokes. AIM OF THE STUDY This study was designed to investigate the scientific rationale behind the use of Burseraceae pitch oleoresin smokes on headache by identifying its chemical constituents and discussing whether they could be beneficial for headache treatment. MATERIALS AND METHODS Two samples of pitch oleoresins were purchased from Amazonian public markets; one of them marketed as "breu preto" (black pitch), and the other as "breu branco" (white pitch). The smoke headspaces produced upon burning these oleoresins were collected and analysed by GC-MS. For comparative purposes, the triterpenoid fingerprints of the oleoresins' dichloromethane extracts and profiles of the essential oils were also obtained by GC-MS - and GC-FID, in the case of the essential oils. RESULTS A total of 32 compounds were detected in black and white pitch oleoresin smokes. All smoke headspaces of the pitch oleoresins shared the presence of volatile terpenoids (e.g., α-terpineol) and triterpenoids (e.g., α-amyrin, β-amyrin, α-amyrone, and β-amyrone). These compounds were also present in the crude resins and could potentially be responsible for anti-inflammatory, antinociceptive and analgesic effects on headache. CONCLUSIONS The pharmacological data on the terpenoids detected in the Burseraceae pitch smokes strongly support their traditional use for headache, but their actual effects upon inhalation have yet to be determined.
IntroductionMass spectrometry in natural products research has been used as a first step to ident... more IntroductionMass spectrometry in natural products research has been used as a first step to identify possible chemical structures and to guide subsequent efforts to isolate novel compounds. Preparations of Ampelozizyphus amazonicus Ducke (AA) are known for their high content of saponins, especially dammarane‐type triterpenoid aglycones. In the Amazon, where it is known as “saracura‐mirá”, roots and bark are widely used for the treatment and prevention of malaria, while the wood is discarded. The extract prepared from the wood is also saponin‐rich, but its exact chemical composition has not been described.ObjectiveThis study provides information on the chemical profiling and tentative structural identification of the major compounds (saponins) present in aqueous and ethanol extracts of bark and wood of AA by mass spectrometry.MethodsThe strategy used to identify compounds present in all samples was ultra‐high‐performance liquid chromatography with an ultraviolet detector coupled to t...
Analysis of the methanol-soluble resin glycosides from the roots of Operculina macrocarpa was ass... more Analysis of the methanol-soluble resin glycosides from the roots of Operculina macrocarpa was assessed by generating NMR profiles of five glycosidic acids obtained through saponification, acetylation, and recycling HPLC purification. Operculinic acid H (1), two novel hexasaccharides, operculinic acids I (2) and J (3), the known purgic acid A (4), and a quinovopyranoside of (-)-(7 R)-hydroxydecanoic acid, operculinic acid K (5), were isolated. Three intact resin glycosides related to 1, the novel macrocarposidic acids A (6) and B (7), in addition to the previously known macrocarposidic acid C (8), were also purified with isovaleroyl, tigloyl, and exogonoyl [(3 S,9 R)-3,6:6,9-diepoxydecanoyl] groups as esterifying residues. A selective intramolecular lactonization was produced to generate a macrocyclic artifact (17) during acetylation of 1, resembling the distinctive structure of the Convolvulaceous resin glycosides.
Hyptis monticola Mart. ex Benth. (Lamiaceae) is an endemic species of altitude regions of Brazil.... more Hyptis monticola Mart. ex Benth. (Lamiaceae) is an endemic species of altitude regions of Brazil. From the leaves of this plant, two 5,6-dihydro-α-pyrones, named monticolides A and B, have been reported as cytotoxic agents against different tumor cell lines. The isolation by high-speed countercurrent chromatography in combination with recycling preparative high-performance liquid chromatography of the undescribed monticolides C-F is presented. These compounds corresponded to a series of related monticolide derivatives differing from each other by the number of acyl substituents. Their characterization by mass spectrometry and nuclear magnetic resonance is also presented, in conjunction with an evidence by a simple chemical correlation for their absolute stereochemistry. The distribution of these chemical markers in extracts of flowers, leaves and branches collected in different seasons by electrospray ionization ion trap mass spectrometry in positive mode was analyzed. Multivariate data analyses indicated that seasonality affects monticolide concentrations in different organs of the aerial parts. Monticolides A-F seem to be present as the original markers of the analyzed plant. However, mono-, di- and triacetylated monticolides can undergo acid-catalyzed transesterifications and their natural yields estimated were affected during the isolation procedures.
Os Yorubás formam um dos maiores grupos étnico-linguísticos da África Ocidental. A Medicina Tradi... more Os Yorubás formam um dos maiores grupos étnico-linguísticos da África Ocidental. A Medicina Tradicional Africana praticada pelos Yorubá inclui uma série de práticas empregadas nos serviços de cuidados gerais de saúde. Com a vinda forçada à América a partir da colonização portuguesa, estes povos trouxeram seus rituais e sua visão de medicina para o Brasil, originando a religião conhecida como Candomblé. O ponto de partida do presente trabalho foi realizar um estudo de revisão sobre a Medicina Tradicional empregada pelos povos africanos de etnia Yorubá na África, traçando um paralelo com seus descendentes praticantes do Candomblé, no Brasil, em uma perspectiva epistemológica, refletindo sobre história, ciências e saúde destes povos, e os desafios à sua consolidação como sistema médico tradicional.
Stingless bee honey (SBH) is gaining attention due to its nutritional, sensorial, and medicinal c... more Stingless bee honey (SBH) is gaining attention due to its nutritional, sensorial, and medicinal characteristics. This study focuses on the combination of physicochemical properties, antioxidant capacity, mineral profile, and mass spectrometry-based fingerprints, using a chemometric approach to differentiate SBH (n = 18) from three different Brazilian biogeographical zones (Caatinga, Cerrado, and Atlantic Forest). The physicochemical properties of SBH varied, resulting in a wide range of water activity, moisture, total soluble solids, pH, and total and free acidity. The Caatinga honey showed the highest and the lowest contents of phenolics and flavonoids, respectively. The antioxidant free-radical scavenging assays demonstrated that the Brazilian SBH has a high antioxidant potential. The mineral profile of honey samples from the Atlantic Forest revealed higher contents of Ca and Fe while the Cerrado and Caatinga honey showed the highest P contents. Partial Least-Squares Discriminant ...
ETHNOPHARMACOLOGICAL RELEVANCE Siparuna species are used in Brazilian Folk Medicine for the treat... more ETHNOPHARMACOLOGICAL RELEVANCE Siparuna species are used in Brazilian Folk Medicine for the treatment and prophylaxis of colds, fever, headache, gastrointestinal disorders and rheumatic pain. AIM OF THE STUDY This study aimed to investigate a possible anti-influenza activity of 25 extracts from leaves of Amazonian S. cristata, S. decipiens, S. glycycarpa, S. reginae and S. sarmentosa based on their folk medicinal uses as well as to investigate their metabolic fingerprinting. The chemical composition of the active extracts was further dereplicated. MATERIAL AND METHODS The chemical composition of the crude EtOH extracts from five Siparuna species were investigated by ESI (±) LC-QTOF-MS2. Organic extracts were obtained by liquid-liquid partition with solvents of increasing polarity, generating 25 extracts which were subjected to a quick DI-ESI (±) IT-MS fingerprint analysis. These extracts were tested against influenza virus replication and cellular toxicity using MDCK cells and influenza A/Michigan/45/2015 (H1N1)pdm09 virus. The compounds in the active BuOH extracts from S. glycycarpa and S. sarmentosa were annotated by ESI (±) LC-QTOF-MS2. RESULTS Analysis of the EtOH extracts revealed the presence of alkaloids and flavonoids, in the positive and negative ionization modes. Out of the 25 organic extracts screened for their antiviral activity, the BuOH extracts from S. glycycarpa and S. sarmentosa were the most active, inhibiting 96.0 ± 1.3 % and 89.5 ± 0.8 % of influenza virus replication 24 h post-infection. These inhibitory effects were manteined until 72hpi. Alkaloids, O- and C-flavonoid glycosides, dihydrochalcones and a procyanidin dimer were annotated in these extracts. CONCLUSIONS The inhibitory effect against influenza A(H1N1)pdm09 virus replication shown by Amazonian Siparuna species corroborates the use of these plants in Brazilian Folk Medicine, showing their potential as anti-influenza agents. These promising results stimulate the continuation of this study with the aim of isolating the compound(s) responsible for this bioactivity, thus contributing to a better knowledge of those species and to the research of natural products with potential anti-influenza activity.
ETHNOPHARMACOLOGICAL RELEVANCE In Latin American Traditional Medicine, the use of Burseraceae ole... more ETHNOPHARMACOLOGICAL RELEVANCE In Latin American Traditional Medicine, the use of Burseraceae oleoresins for headache relief is widespread. In the quilombola (maroon) communities of the municipality of Oriximiná, Pará State, Brazil, Burseraceae oleoresins are burned as incenses to treat headache; an effect attained by inhaling the smokes. AIM OF THE STUDY This study was designed to investigate the scientific rationale behind the use of Burseraceae pitch oleoresin smokes on headache by identifying its chemical constituents and discussing whether they could be beneficial for headache treatment. MATERIALS AND METHODS Two samples of pitch oleoresins were purchased from Amazonian public markets; one of them marketed as "breu preto" (black pitch), and the other as "breu branco" (white pitch). The smoke headspaces produced upon burning these oleoresins were collected and analysed by GC-MS. For comparative purposes, the triterpenoid fingerprints of the oleoresins' dichloromethane extracts and profiles of the essential oils were also obtained by GC-MS - and GC-FID, in the case of the essential oils. RESULTS A total of 32 compounds were detected in black and white pitch oleoresin smokes. All smoke headspaces of the pitch oleoresins shared the presence of volatile terpenoids (e.g., α-terpineol) and triterpenoids (e.g., α-amyrin, β-amyrin, α-amyrone, and β-amyrone). These compounds were also present in the crude resins and could potentially be responsible for anti-inflammatory, antinociceptive and analgesic effects on headache. CONCLUSIONS The pharmacological data on the terpenoids detected in the Burseraceae pitch smokes strongly support their traditional use for headache, but their actual effects upon inhalation have yet to be determined.
IntroductionMass spectrometry in natural products research has been used as a first step to ident... more IntroductionMass spectrometry in natural products research has been used as a first step to identify possible chemical structures and to guide subsequent efforts to isolate novel compounds. Preparations of Ampelozizyphus amazonicus Ducke (AA) are known for their high content of saponins, especially dammarane‐type triterpenoid aglycones. In the Amazon, where it is known as “saracura‐mirá”, roots and bark are widely used for the treatment and prevention of malaria, while the wood is discarded. The extract prepared from the wood is also saponin‐rich, but its exact chemical composition has not been described.ObjectiveThis study provides information on the chemical profiling and tentative structural identification of the major compounds (saponins) present in aqueous and ethanol extracts of bark and wood of AA by mass spectrometry.MethodsThe strategy used to identify compounds present in all samples was ultra‐high‐performance liquid chromatography with an ultraviolet detector coupled to t...
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Papers by Suzana Leitao