Carmen Queiroga - Academia.edu (original) (raw)
Papers by Carmen Queiroga
High-speed countercurrent chromatography as a tool to isolate nerolidol from theBaccharis dracunculifoliavolatile oil
Journal of Essential Oil Research, 2014
Baccharis dracunculifolia is a shrub native to Brazil and an important botanical source for propo... more Baccharis dracunculifolia is a shrub native to Brazil and an important botanical source for propolis production. The essential oil from the leaves of B. dracunculifolia DC (Asteraceae), popularly known as broom oil, presents pharmacological activities and is a raw material in the perfumery and cosmetics industries. The isolation of its major constituent, nerolidol, to a high purity (92.5–93.7%) was possible through the countercurrent chromatography technique. The countercurrent chromatography biphasic solvent system chosen was a mixture of hexane:methanol:water (5:4:1, v/v/v). Isocratic elution was conducted in a tail-to-head manner.
Brazilian Journal of …, 2003
Bacillus subtilis experiments for surface tension evaluation were accomplished with culture mediu... more Bacillus subtilis experiments for surface tension evaluation were accomplished with culture medium containing 0.4% nitrate ions and 4% glucose basic nutrient in the presence of crude oil. Surfactin production was observed by surface tension reduction of the culture broth. Surfactin was isolated from Bacillus subtilis fermented broth, by acid-precipitation followed by extraction with chloroform-methanol. Evaluation of the linear alkanes composition was performed by capillary gas chromatography. We observed a significant reduction of the surface tension of the fermented broth indicating that the biosurfactant production was not inhibited by the crude oil presence, and that the light paraffins might have been consumed.
The Journal of Supercritical Fluids, 2014
Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pha... more Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pharmacological actions. In order to extract and fractionate saponins from Pfaffia glomerata roots and Hebanthe eriantha roots using supercritical technology, fractionated extracts were obtained from a sequential process in fixed bed using supercritical CO 2 (scCO 2 ), ethanol, and water as solvents. All extractions were carried out in four sequential steps, at 50 • C and 300 bar. In the first step, pure scCO 2 was used as solvent, while (a) scCO 2 /etanol (70:30, w/w); (b) ethanol, and (c) ethanol/water (70:30, v/v) were used as solvents in the three subsequent steps. The extracts were analyzed by thin layer chromatography (TLC) and surface tension. The extraction yields of the four steps were 0.16, 0.55, 1.00, and 6.90% for P. glomerata roots, and 0.17, 0.58, 0.89, and 28% for H. eriantha roots, showing a predominance of high polarity compounds in these species. TLC analysis showed that the extraction process was selective according to the polarity of the solvent, and provided extracts containing different saponins, except for scCO 2 extraction. The extracts from the extraction using ethanol + scCO 2 (Step 2) showed the greatest ability to reduce the surface tension of water from 72 mN m −1 (pure water) to 25 mN m −1 , suggesting that this step was the best for extraction of less polar saponins in the extracts. The critical micelle concentration (CMC) values were approximately 2 and 8 g L −1 for P. glomerata and H. Eriantha, respectively. These results confirmed the efficacy of the extraction process under study. (F.A. Cabral).
The Journal of Supercritical Fluids, 2015
The extraction of Eupatorium intermedium flowers was evaluated using supercritical CO 2 (scCO 2 )... more The extraction of Eupatorium intermedium flowers was evaluated using supercritical CO 2 (scCO 2 ) and compressed propane. Experiments were carried out under the following conditions using scCO 2 as the solvent: 15.0, 20.0 and 25.0 MPa and at 303.15, 328.15 and 353.15 K, and the maximum extraction yield was 5.85 wt%. With propane as the solvent the conditions applied were 3.0, 6.5 and 10.0 MPa and 293.15, 313.15 and 333.15 K, and the maximum extraction yield was 9.34 wt%. When scCO 2 was used the pressure had a positive effect on the extraction yield while with the use of propane both variables (pressure and temperature) had a positive effect. Gas chromatographic analysis showed that the major compounds were spathulenol, caryophyllene oxide, caryophyllene (E), germacrene D, bicyclogermacrene and carotol, for the two solvents. The highest values for antioxidant activity were found for the extracts obtained using scCO 2 at 303.15 K and 15 MPa and propane at 333.15 K and 3.0 MPa, determined by the DPPH method and the phosphomolybdenum reduction method. The extract obtained using propane at 293.15 K and 3.0 MPa presented the highest phenolic content. The highest antibacterial activity was observed for the extracts obtained with scCO 2 against Staphylococcus aureus and Listeria monocytogenes.
Comparison of volatile and polyphenolic compounds in Brazilian green propolis and its botanical origin Baccharis dracunculifolia
Ciencia E Tecnologia De Alimentos, 2008
Ethanolic extracts and essential oils from Green Propolis from southeastern Brazil and leaf buds ... more Ethanolic extracts and essential oils from Green Propolis from southeastern Brazil and leaf buds from its botanical origin Baccharis dracunculifolia were analyzed by Reversed Phase High Performance Liquid Chromatography (RP-HPLC), Reversed Phase High ...
ChemInform, 1996
Three New Oxygenated Cadinanes from Baccharis Species.
Three new oxygenated cadinanes from Baccharis species
Phytochemistry, 1996
Synthesis of several (±)-[4S-(4β,4aβ,8aα)]-1,6-dimethyl-4-(1 methylethyl)-1,2,3,4,5,8,8a-octahydr... more Synthesis of several (±)-[4S-(4β,4aβ,8aα)]-1,6-dimethyl-4-(1 methylethyl)-1,2,3,4,5,8,8a-octahydro-1-naphthalenol derivatives (cadinanol derivatives) provided the necessary evidence for the identification of three novel cadinane derivatives [(±)-[1S-(1β, 4β, 4aβ, 8aα)]-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,8,8a-octahydro-1-naphthalenol 11a, (±)-[1S-(1β, 4β, 4aβ, 4aβ, 6α, 7α, 8aα)]-6, 7-epoxide-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,6,7,8,8a-decahydro-1- naphthalenol 14 and (±)-[1S-(1β,4β,4aβ,6β,8aα)]-1,6-dimethyl-4-(1-methylethyl-1,2,3,4,4a,5,6,7,8,8a-decahydro-1,6-naphthalenediol 15] detected, in the essential oils of, B. platipoda. Compound 14 was also detected in B. tridentata. The synthetic compounds were characterized by
Composition of the Essential Oil of Vassoura
Journal Of The Brazilian Chemical Society, 1990
Analysis of Baccharis dracunculifolia DC essential oil was accomplished by using several techniqu... more Analysis of Baccharis dracunculifolia DC essential oil was accomplished by using several techniques as selective extraction, column and thin layer chromatography, argentation chromatography and GC/MS. We have identified 43 components. Major components and ...
Fitoterapia, 2007
The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). T... more The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). The antimicrobial activity tests indicated that the oil was effective against Rhodococcus equi (0.60 mg/ml) and Staphylococcus epidermides (0.15 mg/ml).
The Journal of Supercritical Fluids, 2011
Different extraction processes were employed to extract the polyphenolic compounds from pitanga (... more Different extraction processes were employed to extract the polyphenolic compounds from pitanga (Eugenia uniflora L.) leaves: a one-step process using water, ethanol or supercritical CO 2 as solvents, and a two-step process using supercritical CO 2 followed by either water or ethanol. The total polyphenolic compounds, total flavonoids and antioxidant activity were determined in all the extracts obtained. The process performance was evaluated with respect to three variables: global extraction yield, concentration and yield of both polyphenols and flavonoids in the extracts. For the one-step extraction, the results showed that the extraction yield increased with solvent polarity. For the two-step process, the results suggested that water was more efficient in extracting the phenolic compounds from E. uniflora when the matrix was previously extracted with scCO 2 . With respect to the antioxidant activity, the ethanolic extracts obtained from both processes, using either the DPPH radical scavenging method or the -carotene bleaching method, presented high antioxidant activities.
Sequential extraction of bioactive compounds from Melia azedarach L. in fixed bed extractor using CO2, ethanol and water
The Journal of Supercritical Fluids, 2014
ABSTRACT Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioa... more ABSTRACT Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioactive compounds of interest. The present study aimed to extract bioactive compounds from M. azedarach fruits by a sequential process in fixed bed using various solvent mixtures. Extractions were performed at 50 °C and 300 bar in four sequential steps using supercritical CO2 (scCO2), scCO2/ethanol, pure ethanol, and ethanol/water mixture as solvents, respectively. The efficacy of the extraction process was evaluated by extraction yield and kinetics, and analysis of extracts by: (1) thin layer chromatography (TLC), (2) phenolics content, (3) reduction of surface tension of water, (4) gas chromatography (GC–MS), (5) electrospray ionization mass spectrometry (ESI–MS) and (6) antiviral activity. The overall extraction yield reached 45% and TLC analysis showed extracts with different composition. extract obtained from CO2/ethanol mixture (SCEE) exhibited the greatest ability to reduce surface tension of water from 72.4 mN m−1 [1] of pure water to 26.9 mN m−1 of an aqueous solution of 40 g L−1. The highest phenolics contents were observed in both the hydroalcoholic extract and scCO2/ethanolic extract. Volatile oils were not detected in the supercritical extracts by GC–MS. MS analyses identified the fatty acids: linoleic, palmitic and myristic acid in the supercritical extract (SCE), and the phenolics: caffeic acid and malic acid in the other extracts. In addition, SCE and SCEE extracts showed significant inhibition percentage against Herpes Simplex Virus Type 1. The extraction process proposed in the present study produced extracts with significant potential for application in food and pharmaceutical industries.
Journal of Essential Oil Research, 2008
The essential oils of the leaves and fruits from bay (Laurus nobilis L.) grown in Antakya, Yaylad... more The essential oils of the leaves and fruits from bay (Laurus nobilis L.) grown in Antakya, Yayladagi and Samandagi were isolated by solvent extraction and analysed by capillary gas chromatography (GC), gas chromatography and mass spectrometry (GC/MS). In Antakya, Yayladagi and Samandagi the chemical compositions of the fruits and leaves were similar according to qualitative and quantitative analysis. Although in both fruits and leaves the major component was found to be 1.8-Cineole a concentration of about 50% compared with essential oils. The composition of the essential oil from the leaves has high content of 1.8-Cineole, Sabinene and α-Terpinyl acetate, but a low content of α-Pinene, α-Phellandrene and trans-β-osimen. 1.8-Cineole was found major component of the leaves essential oil collected from Samandagi (59.94%) which is sea coast of region. Interestingly, α-Pinene, β-Pinene, α-Phellandrene, 1.8-Cineole and trans-β-osimen were found the major components of fruits of Laurus nobilis L. harvested from Antakya, Yayladagi and Samandagi. Trans-β-osimen was detected as the major component of fruits essential oil collected again from Samandagi (28.35%)
Journal of Ethnopharmacology, 2000
An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity ... more An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity of friedelan-3b-ol 1 and friedelin 2. The two triterpenes isolated from the leaves of Maytenus ilicifolia, did not decrease gastric ulcers when tested on indometacine induced ulcer model in rats.
Revista Brasileira de Farmacognosia, 2012
Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitagua... more Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitaguará, is a native and endemic tree from São Paulo and Rio de Janeiro States, Brazil. Based in the information that anticholinesterasic derivatives could act as new prototypes to treatment of Alzheimer disease, this work describes the fractionation guided by evaluation of the anticholinesterase activity of the ethanolic stems extract from C. fontanesianus. This procedure afforded the alkaloids dictamnine (1), γ-fagarine (2), skimianine (3), and 2-phenyl-1-methyl-4-quinolone (4), as well as the coumarin marmesin (5).
Study of the Variation of the Composition of the Essential Oil of Leaves and Flowers of Achyrocline alata (D.C.) Along a Period of the Day
Journal of Essential Oil Research, 2002
Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the peri... more Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the period of 7 AM until 2 PM, in hourly intervals. The leaf and flower oils were obtained by hydrodistillation. Analyses of the oils by GC/MS reveals that the main components of the leaf oil varied as follows: α-pinene (1.7–7.6%), 1-octen-3-ol (1.7–5.6%), 1,8-cineole (0.4–5.1%), β-caryophyllene (14.6–16.7%), α-humulene
High-speed countercurrent chromatography as a tool to isolate nerolidol from theBaccharis dracunculifoliavolatile oil
Journal of Essential Oil Research, 2014
Baccharis dracunculifolia is a shrub native to Brazil and an important botanical source for propo... more Baccharis dracunculifolia is a shrub native to Brazil and an important botanical source for propolis production. The essential oil from the leaves of B. dracunculifolia DC (Asteraceae), popularly known as broom oil, presents pharmacological activities and is a raw material in the perfumery and cosmetics industries. The isolation of its major constituent, nerolidol, to a high purity (92.5–93.7%) was possible through the countercurrent chromatography technique. The countercurrent chromatography biphasic solvent system chosen was a mixture of hexane:methanol:water (5:4:1, v/v/v). Isocratic elution was conducted in a tail-to-head manner.
Brazilian Journal of …, 2003
Bacillus subtilis experiments for surface tension evaluation were accomplished with culture mediu... more Bacillus subtilis experiments for surface tension evaluation were accomplished with culture medium containing 0.4% nitrate ions and 4% glucose basic nutrient in the presence of crude oil. Surfactin production was observed by surface tension reduction of the culture broth. Surfactin was isolated from Bacillus subtilis fermented broth, by acid-precipitation followed by extraction with chloroform-methanol. Evaluation of the linear alkanes composition was performed by capillary gas chromatography. We observed a significant reduction of the surface tension of the fermented broth indicating that the biosurfactant production was not inhibited by the crude oil presence, and that the light paraffins might have been consumed.
The Journal of Supercritical Fluids, 2014
Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pha... more Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pharmacological actions. In order to extract and fractionate saponins from Pfaffia glomerata roots and Hebanthe eriantha roots using supercritical technology, fractionated extracts were obtained from a sequential process in fixed bed using supercritical CO 2 (scCO 2 ), ethanol, and water as solvents. All extractions were carried out in four sequential steps, at 50 • C and 300 bar. In the first step, pure scCO 2 was used as solvent, while (a) scCO 2 /etanol (70:30, w/w); (b) ethanol, and (c) ethanol/water (70:30, v/v) were used as solvents in the three subsequent steps. The extracts were analyzed by thin layer chromatography (TLC) and surface tension. The extraction yields of the four steps were 0.16, 0.55, 1.00, and 6.90% for P. glomerata roots, and 0.17, 0.58, 0.89, and 28% for H. eriantha roots, showing a predominance of high polarity compounds in these species. TLC analysis showed that the extraction process was selective according to the polarity of the solvent, and provided extracts containing different saponins, except for scCO 2 extraction. The extracts from the extraction using ethanol + scCO 2 (Step 2) showed the greatest ability to reduce the surface tension of water from 72 mN m −1 (pure water) to 25 mN m −1 , suggesting that this step was the best for extraction of less polar saponins in the extracts. The critical micelle concentration (CMC) values were approximately 2 and 8 g L −1 for P. glomerata and H. Eriantha, respectively. These results confirmed the efficacy of the extraction process under study. (F.A. Cabral).
The Journal of Supercritical Fluids, 2015
The extraction of Eupatorium intermedium flowers was evaluated using supercritical CO 2 (scCO 2 )... more The extraction of Eupatorium intermedium flowers was evaluated using supercritical CO 2 (scCO 2 ) and compressed propane. Experiments were carried out under the following conditions using scCO 2 as the solvent: 15.0, 20.0 and 25.0 MPa and at 303.15, 328.15 and 353.15 K, and the maximum extraction yield was 5.85 wt%. With propane as the solvent the conditions applied were 3.0, 6.5 and 10.0 MPa and 293.15, 313.15 and 333.15 K, and the maximum extraction yield was 9.34 wt%. When scCO 2 was used the pressure had a positive effect on the extraction yield while with the use of propane both variables (pressure and temperature) had a positive effect. Gas chromatographic analysis showed that the major compounds were spathulenol, caryophyllene oxide, caryophyllene (E), germacrene D, bicyclogermacrene and carotol, for the two solvents. The highest values for antioxidant activity were found for the extracts obtained using scCO 2 at 303.15 K and 15 MPa and propane at 333.15 K and 3.0 MPa, determined by the DPPH method and the phosphomolybdenum reduction method. The extract obtained using propane at 293.15 K and 3.0 MPa presented the highest phenolic content. The highest antibacterial activity was observed for the extracts obtained with scCO 2 against Staphylococcus aureus and Listeria monocytogenes.
Comparison of volatile and polyphenolic compounds in Brazilian green propolis and its botanical origin Baccharis dracunculifolia
Ciencia E Tecnologia De Alimentos, 2008
Ethanolic extracts and essential oils from Green Propolis from southeastern Brazil and leaf buds ... more Ethanolic extracts and essential oils from Green Propolis from southeastern Brazil and leaf buds from its botanical origin Baccharis dracunculifolia were analyzed by Reversed Phase High Performance Liquid Chromatography (RP-HPLC), Reversed Phase High ...
ChemInform, 1996
Three New Oxygenated Cadinanes from Baccharis Species.
Three new oxygenated cadinanes from Baccharis species
Phytochemistry, 1996
Synthesis of several (±)-[4S-(4β,4aβ,8aα)]-1,6-dimethyl-4-(1 methylethyl)-1,2,3,4,5,8,8a-octahydr... more Synthesis of several (±)-[4S-(4β,4aβ,8aα)]-1,6-dimethyl-4-(1 methylethyl)-1,2,3,4,5,8,8a-octahydro-1-naphthalenol derivatives (cadinanol derivatives) provided the necessary evidence for the identification of three novel cadinane derivatives [(±)-[1S-(1β, 4β, 4aβ, 8aα)]-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,8,8a-octahydro-1-naphthalenol 11a, (±)-[1S-(1β, 4β, 4aβ, 4aβ, 6α, 7α, 8aα)]-6, 7-epoxide-1,6-dimethyl-4-(1-methylethyl)-1,2,3,4,4a,5,6,7,8,8a-decahydro-1- naphthalenol 14 and (±)-[1S-(1β,4β,4aβ,6β,8aα)]-1,6-dimethyl-4-(1-methylethyl-1,2,3,4,4a,5,6,7,8,8a-decahydro-1,6-naphthalenediol 15] detected, in the essential oils of, B. platipoda. Compound 14 was also detected in B. tridentata. The synthetic compounds were characterized by
Composition of the Essential Oil of Vassoura
Journal Of The Brazilian Chemical Society, 1990
Analysis of Baccharis dracunculifolia DC essential oil was accomplished by using several techniqu... more Analysis of Baccharis dracunculifolia DC essential oil was accomplished by using several techniques as selective extraction, column and thin layer chromatography, argentation chromatography and GC/MS. We have identified 43 components. Major components and ...
Fitoterapia, 2007
The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). T... more The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). The antimicrobial activity tests indicated that the oil was effective against Rhodococcus equi (0.60 mg/ml) and Staphylococcus epidermides (0.15 mg/ml).
The Journal of Supercritical Fluids, 2011
Different extraction processes were employed to extract the polyphenolic compounds from pitanga (... more Different extraction processes were employed to extract the polyphenolic compounds from pitanga (Eugenia uniflora L.) leaves: a one-step process using water, ethanol or supercritical CO 2 as solvents, and a two-step process using supercritical CO 2 followed by either water or ethanol. The total polyphenolic compounds, total flavonoids and antioxidant activity were determined in all the extracts obtained. The process performance was evaluated with respect to three variables: global extraction yield, concentration and yield of both polyphenols and flavonoids in the extracts. For the one-step extraction, the results showed that the extraction yield increased with solvent polarity. For the two-step process, the results suggested that water was more efficient in extracting the phenolic compounds from E. uniflora when the matrix was previously extracted with scCO 2 . With respect to the antioxidant activity, the ethanolic extracts obtained from both processes, using either the DPPH radical scavenging method or the -carotene bleaching method, presented high antioxidant activities.
Sequential extraction of bioactive compounds from Melia azedarach L. in fixed bed extractor using CO2, ethanol and water
The Journal of Supercritical Fluids, 2014
ABSTRACT Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioa... more ABSTRACT Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioactive compounds of interest. The present study aimed to extract bioactive compounds from M. azedarach fruits by a sequential process in fixed bed using various solvent mixtures. Extractions were performed at 50 °C and 300 bar in four sequential steps using supercritical CO2 (scCO2), scCO2/ethanol, pure ethanol, and ethanol/water mixture as solvents, respectively. The efficacy of the extraction process was evaluated by extraction yield and kinetics, and analysis of extracts by: (1) thin layer chromatography (TLC), (2) phenolics content, (3) reduction of surface tension of water, (4) gas chromatography (GC–MS), (5) electrospray ionization mass spectrometry (ESI–MS) and (6) antiviral activity. The overall extraction yield reached 45% and TLC analysis showed extracts with different composition. extract obtained from CO2/ethanol mixture (SCEE) exhibited the greatest ability to reduce surface tension of water from 72.4 mN m−1 [1] of pure water to 26.9 mN m−1 of an aqueous solution of 40 g L−1. The highest phenolics contents were observed in both the hydroalcoholic extract and scCO2/ethanolic extract. Volatile oils were not detected in the supercritical extracts by GC–MS. MS analyses identified the fatty acids: linoleic, palmitic and myristic acid in the supercritical extract (SCE), and the phenolics: caffeic acid and malic acid in the other extracts. In addition, SCE and SCEE extracts showed significant inhibition percentage against Herpes Simplex Virus Type 1. The extraction process proposed in the present study produced extracts with significant potential for application in food and pharmaceutical industries.
Journal of Essential Oil Research, 2008
The essential oils of the leaves and fruits from bay (Laurus nobilis L.) grown in Antakya, Yaylad... more The essential oils of the leaves and fruits from bay (Laurus nobilis L.) grown in Antakya, Yayladagi and Samandagi were isolated by solvent extraction and analysed by capillary gas chromatography (GC), gas chromatography and mass spectrometry (GC/MS). In Antakya, Yayladagi and Samandagi the chemical compositions of the fruits and leaves were similar according to qualitative and quantitative analysis. Although in both fruits and leaves the major component was found to be 1.8-Cineole a concentration of about 50% compared with essential oils. The composition of the essential oil from the leaves has high content of 1.8-Cineole, Sabinene and α-Terpinyl acetate, but a low content of α-Pinene, α-Phellandrene and trans-β-osimen. 1.8-Cineole was found major component of the leaves essential oil collected from Samandagi (59.94%) which is sea coast of region. Interestingly, α-Pinene, β-Pinene, α-Phellandrene, 1.8-Cineole and trans-β-osimen were found the major components of fruits of Laurus nobilis L. harvested from Antakya, Yayladagi and Samandagi. Trans-β-osimen was detected as the major component of fruits essential oil collected again from Samandagi (28.35%)
Journal of Ethnopharmacology, 2000
An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity ... more An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity of friedelan-3b-ol 1 and friedelin 2. The two triterpenes isolated from the leaves of Maytenus ilicifolia, did not decrease gastric ulcers when tested on indometacine induced ulcer model in rats.
Revista Brasileira de Farmacognosia, 2012
Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitagua... more Conchocarpus fontanesianus (A. St.-Hill.) Kallunki & Pirani, Rutaceae, popularly known as pitaguará, is a native and endemic tree from São Paulo and Rio de Janeiro States, Brazil. Based in the information that anticholinesterasic derivatives could act as new prototypes to treatment of Alzheimer disease, this work describes the fractionation guided by evaluation of the anticholinesterase activity of the ethanolic stems extract from C. fontanesianus. This procedure afforded the alkaloids dictamnine (1), γ-fagarine (2), skimianine (3), and 2-phenyl-1-methyl-4-quinolone (4), as well as the coumarin marmesin (5).
Study of the Variation of the Composition of the Essential Oil of Leaves and Flowers of Achyrocline alata (D.C.) Along a Period of the Day
Journal of Essential Oil Research, 2002
Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the peri... more Leaves and flowers of Achyrocline alata were picked in an experimental garden throughout the period of 7 AM until 2 PM, in hourly intervals. The leaf and flower oils were obtained by hydrodistillation. Analyses of the oils by GC/MS reveals that the main components of the leaf oil varied as follows: α-pinene (1.7–7.6%), 1-octen-3-ol (1.7–5.6%), 1,8-cineole (0.4–5.1%), β-caryophyllene (14.6–16.7%), α-humulene