The sphere of natural products is an abundant source for discovery of therapeutic drugs for the t... more The sphere of natural products is an abundant source for discovery of therapeutic drugs for the treatment of neglected parasitic diseases. Various classes of chemical substances displayed antiprotozoal activity, such as alkaloids, terpenoids, saponins, and flavonoids. The highly functional saponins are found predominantly in plants and are frequently consumed in foods, beverages, and medicines. This class of chemical substance has structurally one or more glycoside moieties linked to a triterpenoid or steroid. Saponins demonstrated to be very valuable therapeutic targets whose potential is still to be explored and that may be useful for the development of new antiprotozoal drugs options.
Alpinia zerumbet (Zingiberaceae) is an important medicinal plant found in several countries and u... more Alpinia zerumbet (Zingiberaceae) is an important medicinal plant found in several countries and used in folk medicine. The hypotensive and anxiolytic effects of the preparations made from this plant are mainly attributed to flavonoids and kavalactones, respectively. The aim of this study was to compare infusions, hydroalcohol extracts and tinctures obtained with fresh and dried leaves of A. zerumbet collected in two Brazilian cities: Rio de Janeiro/RJ and Brasilia/DF. Colorimetric methods were used to evaluate the antioxidant activity, total phenolic and total flavonoid contents of the extracts. The flavonoids and dihydro-5,6-dehydrokavain (DDK) contents were analyzed by HPLC-DAD and the volatile compounds were evaluated by headspace solid phase extraction (SPE) followed by GC-MS analyses, which also evaluated the nonpolar fractions. The fresh and dried leaves from both Brazilian cities contain high amounts of flavonoids with antioxidant activity. The 80 % hydroalcohol extract prepared with fresh leaves collected in Brasilia exhibited the highest antioxidant activity by the phosphomolybdenum and DPPH methods. HPLC analyses of the infusions prepared with fresh leaves collected in Rio de Janeiro showed the highest DDK content, 6.63 mg/g of the extract. The GC-MS analyses of the nonpolar fractions from the aqueous extracts, from both cities, showed the presence of two major substances, the kavalactones DDK and 5,6-dehydrokavain. The evaluation of the loss of volatile substances by headspace SPE showed that even after a storage time of 30 days, there were still volatile substances in the dried plant material from both cities. In addition, the loss of terpinen-4-ol and γ-terpinene from the fresh leaves was very low, showing the slow release of these substances under the studied conditions. In conclusion, this work shows that the chemical standardization of A. zerumbet preparations contains terpenoids, kavalactones and phenolic compounds related to the biological activities which are important to corroborate the different uses of this species. anti-hypertensive properties (Indrayan et al., 2010; Araujo et al., 2011; Mendonça et al., 1991; Laranja et al., 1992). It is used in foodstuffs and traditional medicines in Japan (Teschke and Xuan, 2018). There is already a herbal medicinal product for topical administration marketed in Brazil, called Ziclague® (Hebron, 2020), which is used as an adjuvant in the treatment of muscular spasticity (Freitas, 2016). Furthermore, the Alpinia species have been extensively investigated for their chemical compositions and biological activities (Ma et al., 2017). In Brazil, A. zerumbet is popularly known as "Colônia" and its leaves are sold for use in tea, as an infusion for the treatment of arterial hypertension and anxiety symptoms (Araújo et al., 2009). According to
A new dammarane triterpene named mauritic acid (1) was isolated from the roots of Mauritia flexuo... more A new dammarane triterpene named mauritic acid (1) was isolated from the roots of Mauritia flexuosa L.f. The complete structural assignment of this new compound was elucidated from spectroscopic methods. Moreover, this compound was evaluated for its cytotoxicity against human cancer cell lines (OVCAR-8, PCM3, NCIH358M and different leukaemia cell strains). The mauritic acid presented significant cytotoxicity against OVCAR-8, PCM3 and NCIH358M cell lines with IC50 3.02, 2.39 and 6.19 μM, respectively. The triterpenes 1 and 2 were also tested for their antimicrobial activity against 15 strains of microorganisms, including fungi and bacteria, with the best minimal inhibitory concentration values ranging from 50.8 to 203.5 μM.
Himatanthus species (Apocynaceae) are popularly used in Brazil to treat inflammation, ulcer, and ... more Himatanthus species (Apocynaceae) are popularly used in Brazil to treat inflammation, ulcer, and cancer [1-4]. The genus is chemically characterized by the occurrence of iridoids [2, 5, 6]. Himatanthus sucuuba (Spruce) Woodson grows in the Amazon region, and several chemical research reports on its latex and barks led to the isolation of iridoids such as plumericin and isoplumericin and triterpenes such as D-amyrin and lupeol esters [1, 5, 7]. These components are usually associated with the activity of this genus. H. attenuatus (Benth.) Woodson is a tree species distributed in Colombia, Venezuela, Brazil, and Bolivia. Unlike H. sucuuba, there are few studies on H. attenuatus related only to taxonomy, morphology, and screening studies [8-10]. The aim of this work was to contribute to the knowledge of the genus Himatanthus by comparing the hexane and dichloromethane extracts of the scarcely studied species H. attenuatus with the extracts of H. sucuuba using gas chromatography coupled to mass spectrometry (GC-MS) analyses. This procedure also furnished the chromatography fingerprint of both species, popularly known as sucuba in Amazonas and Acre states, among other names. Roots of H. attenuatus and H. sucuuba were collected in the Brazilian Amazon region, and the herbaria vouchers were compared with those previously deposited: 17590 (UFAC Herbarium, Acre State) and 180453 (INPA Herbarium, Amazonas State), respectively. Both plant materials were dried in the oven with air circulation at 35qC for 24 h. Finely triturated roots of H. attenuatus and H. sucuuba (0.5 g each) were successively macerated with agitation five times with hexane (1.2 L/extraction) and CH 2 Cl 2 (1.2 L/extraction). Extracts were concentrated under reduced pressure, yielding (p/p) 1.9% of hexane extract of H. attenuatus (HA-HX), 1.1% of CH 2 Cl 2 extract of H. attenuatus (HA-DC), 1.2% of hexane extract of H. sucuuba (HS-HX), and 2.3% of CH 2 Cl 2 extract of H. sucuuba (HS-DC). Their chemical compositions are shown in Table 1. Extracts were analyzed by GC-MS on an Agilent 6890N GC coupled to a quadripolar mass spectrometer (Agilent 5973N), with ionization by electronic impact (70 eV). Analyses were performed in triplicate, and the injected volume was 1 PL, in splitless mode. The apparatus was fitted with a DB-5MS column (30 m u 0.25 mm I.D., 0.25 Pm phase film). The injector temperature was 270qC, ion-source 70 eV, detector 230qC, and scan range 40-700 m/z. The column temperature varied from 70qC to 305qC at a rate of 5qC/min. Helium was the carrier gas at flow rate 1 mL/min. Interpretation and identification of the fragmentation mass spectrum were carried out by comparison with the Wiley NBS mass spectrum database. Results are expressed as relative percentage of peak area in the chromatogram (Table 1). As shown in Table 1, free fatty acids and their esters were detected in both species, and an important content of palmitic acid was found in the CH 2 Cl 2 extract of H. sucuuba (11.5%). The steroid, sitosterol, was present in H. sucuuba extracts.
A familia Apocynaceae apresenta uma grande diversidade de metabolitos secundarios, com potencial ... more A familia Apocynaceae apresenta uma grande diversidade de metabolitos secundarios, com potencial biologico e farmaceutico, o que tem despertado grande interesse nos estudos de seus generos. O genero Himatanthus possui treze especies que estao amplamente distribuidas na regiao norte do Brasil. A especie da regiao amazonica, Himatanthus sucuuba, e latescente, arborea, cujo tronco e ereto e a casca rugosa, popularmente conhecida como sucuba, sucuuba ou janaguba. O latex, cascas e folhas sao utilizados na medicina popular como antitumoral, antifungico, antianemico, vermifugo e no tratamento de gastrites e artrites. No presente estudo as raizes de H. sucuuba foram utilizadas para a obtencao dos extratos hexano, diclorometano e metanol. Do extrato hexano foi isolada a mistura dos cinamatos de lupeol, α e β-amirina. O extrato diclorometano foi submetido a fracionamento cromatografico fornecendo os iridoides plumericina, isoplumericina, plumieridina e o esteroide sitosterol. Do extrato meta...
The sphere of natural products is an abundant source for discovery of therapeutic drugs for the t... more The sphere of natural products is an abundant source for discovery of therapeutic drugs for the treatment of neglected parasitic diseases. Various classes of chemical substances displayed antiprotozoal activity, such as alkaloids, terpenoids, saponins, and flavonoids. The highly functional saponins are found predominantly in plants and are frequently consumed in foods, beverages, and medicines. This class of chemical substance has structurally one or more glycoside moieties linked to a triterpenoid or steroid. Saponins demonstrated to be very valuable therapeutic targets whose potential is still to be explored and that may be useful for the development of new antiprotozoal drugs options.
Alpinia zerumbet (Zingiberaceae) is an important medicinal plant found in several countries and u... more Alpinia zerumbet (Zingiberaceae) is an important medicinal plant found in several countries and used in folk medicine. The hypotensive and anxiolytic effects of the preparations made from this plant are mainly attributed to flavonoids and kavalactones, respectively. The aim of this study was to compare infusions, hydroalcohol extracts and tinctures obtained with fresh and dried leaves of A. zerumbet collected in two Brazilian cities: Rio de Janeiro/RJ and Brasilia/DF. Colorimetric methods were used to evaluate the antioxidant activity, total phenolic and total flavonoid contents of the extracts. The flavonoids and dihydro-5,6-dehydrokavain (DDK) contents were analyzed by HPLC-DAD and the volatile compounds were evaluated by headspace solid phase extraction (SPE) followed by GC-MS analyses, which also evaluated the nonpolar fractions. The fresh and dried leaves from both Brazilian cities contain high amounts of flavonoids with antioxidant activity. The 80 % hydroalcohol extract prepared with fresh leaves collected in Brasilia exhibited the highest antioxidant activity by the phosphomolybdenum and DPPH methods. HPLC analyses of the infusions prepared with fresh leaves collected in Rio de Janeiro showed the highest DDK content, 6.63 mg/g of the extract. The GC-MS analyses of the nonpolar fractions from the aqueous extracts, from both cities, showed the presence of two major substances, the kavalactones DDK and 5,6-dehydrokavain. The evaluation of the loss of volatile substances by headspace SPE showed that even after a storage time of 30 days, there were still volatile substances in the dried plant material from both cities. In addition, the loss of terpinen-4-ol and γ-terpinene from the fresh leaves was very low, showing the slow release of these substances under the studied conditions. In conclusion, this work shows that the chemical standardization of A. zerumbet preparations contains terpenoids, kavalactones and phenolic compounds related to the biological activities which are important to corroborate the different uses of this species. anti-hypertensive properties (Indrayan et al., 2010; Araujo et al., 2011; Mendonça et al., 1991; Laranja et al., 1992). It is used in foodstuffs and traditional medicines in Japan (Teschke and Xuan, 2018). There is already a herbal medicinal product for topical administration marketed in Brazil, called Ziclague® (Hebron, 2020), which is used as an adjuvant in the treatment of muscular spasticity (Freitas, 2016). Furthermore, the Alpinia species have been extensively investigated for their chemical compositions and biological activities (Ma et al., 2017). In Brazil, A. zerumbet is popularly known as "Colônia" and its leaves are sold for use in tea, as an infusion for the treatment of arterial hypertension and anxiety symptoms (Araújo et al., 2009). According to
A new dammarane triterpene named mauritic acid (1) was isolated from the roots of Mauritia flexuo... more A new dammarane triterpene named mauritic acid (1) was isolated from the roots of Mauritia flexuosa L.f. The complete structural assignment of this new compound was elucidated from spectroscopic methods. Moreover, this compound was evaluated for its cytotoxicity against human cancer cell lines (OVCAR-8, PCM3, NCIH358M and different leukaemia cell strains). The mauritic acid presented significant cytotoxicity against OVCAR-8, PCM3 and NCIH358M cell lines with IC50 3.02, 2.39 and 6.19 μM, respectively. The triterpenes 1 and 2 were also tested for their antimicrobial activity against 15 strains of microorganisms, including fungi and bacteria, with the best minimal inhibitory concentration values ranging from 50.8 to 203.5 μM.
Himatanthus species (Apocynaceae) are popularly used in Brazil to treat inflammation, ulcer, and ... more Himatanthus species (Apocynaceae) are popularly used in Brazil to treat inflammation, ulcer, and cancer [1-4]. The genus is chemically characterized by the occurrence of iridoids [2, 5, 6]. Himatanthus sucuuba (Spruce) Woodson grows in the Amazon region, and several chemical research reports on its latex and barks led to the isolation of iridoids such as plumericin and isoplumericin and triterpenes such as D-amyrin and lupeol esters [1, 5, 7]. These components are usually associated with the activity of this genus. H. attenuatus (Benth.) Woodson is a tree species distributed in Colombia, Venezuela, Brazil, and Bolivia. Unlike H. sucuuba, there are few studies on H. attenuatus related only to taxonomy, morphology, and screening studies [8-10]. The aim of this work was to contribute to the knowledge of the genus Himatanthus by comparing the hexane and dichloromethane extracts of the scarcely studied species H. attenuatus with the extracts of H. sucuuba using gas chromatography coupled to mass spectrometry (GC-MS) analyses. This procedure also furnished the chromatography fingerprint of both species, popularly known as sucuba in Amazonas and Acre states, among other names. Roots of H. attenuatus and H. sucuuba were collected in the Brazilian Amazon region, and the herbaria vouchers were compared with those previously deposited: 17590 (UFAC Herbarium, Acre State) and 180453 (INPA Herbarium, Amazonas State), respectively. Both plant materials were dried in the oven with air circulation at 35qC for 24 h. Finely triturated roots of H. attenuatus and H. sucuuba (0.5 g each) were successively macerated with agitation five times with hexane (1.2 L/extraction) and CH 2 Cl 2 (1.2 L/extraction). Extracts were concentrated under reduced pressure, yielding (p/p) 1.9% of hexane extract of H. attenuatus (HA-HX), 1.1% of CH 2 Cl 2 extract of H. attenuatus (HA-DC), 1.2% of hexane extract of H. sucuuba (HS-HX), and 2.3% of CH 2 Cl 2 extract of H. sucuuba (HS-DC). Their chemical compositions are shown in Table 1. Extracts were analyzed by GC-MS on an Agilent 6890N GC coupled to a quadripolar mass spectrometer (Agilent 5973N), with ionization by electronic impact (70 eV). Analyses were performed in triplicate, and the injected volume was 1 PL, in splitless mode. The apparatus was fitted with a DB-5MS column (30 m u 0.25 mm I.D., 0.25 Pm phase film). The injector temperature was 270qC, ion-source 70 eV, detector 230qC, and scan range 40-700 m/z. The column temperature varied from 70qC to 305qC at a rate of 5qC/min. Helium was the carrier gas at flow rate 1 mL/min. Interpretation and identification of the fragmentation mass spectrum were carried out by comparison with the Wiley NBS mass spectrum database. Results are expressed as relative percentage of peak area in the chromatogram (Table 1). As shown in Table 1, free fatty acids and their esters were detected in both species, and an important content of palmitic acid was found in the CH 2 Cl 2 extract of H. sucuuba (11.5%). The steroid, sitosterol, was present in H. sucuuba extracts.
A familia Apocynaceae apresenta uma grande diversidade de metabolitos secundarios, com potencial ... more A familia Apocynaceae apresenta uma grande diversidade de metabolitos secundarios, com potencial biologico e farmaceutico, o que tem despertado grande interesse nos estudos de seus generos. O genero Himatanthus possui treze especies que estao amplamente distribuidas na regiao norte do Brasil. A especie da regiao amazonica, Himatanthus sucuuba, e latescente, arborea, cujo tronco e ereto e a casca rugosa, popularmente conhecida como sucuba, sucuuba ou janaguba. O latex, cascas e folhas sao utilizados na medicina popular como antitumoral, antifungico, antianemico, vermifugo e no tratamento de gastrites e artrites. No presente estudo as raizes de H. sucuuba foram utilizadas para a obtencao dos extratos hexano, diclorometano e metanol. Do extrato hexano foi isolada a mistura dos cinamatos de lupeol, α e β-amirina. O extrato diclorometano foi submetido a fracionamento cromatografico fornecendo os iridoides plumericina, isoplumericina, plumieridina e o esteroide sitosterol. Do extrato meta...
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