Daniela Navarro | Universidade Federal de Pernambuco (original) (raw)
Papers by Daniela Navarro
Dengue fever has spread worldwide and affects millions of people every year in tropical and subtr... more Dengue fever has spread worldwide and affects millions of people every year in tropical and subtropical regions of Africa, Asia, Europe and America. Since there is no effective vaccine against the dengue virus, prevention of disease transmission depends entirely on regulating the vector (Aedes aegypti) or interrupting human-vector contact. The aim of this study was to assess the oviposition deterrent activity of essential oils of three cultivars of torch ginger (Etlingera elatior, Zingiberaceae) against the dengue mosquito. Analysis of the oils by gas chromatography (GC)—mass spectrometry revealed the presence of 43 constituents, of which α-pinene, dodecanal and n-dodecanol were the major components in all cultivars. Solutions containing 100 ppm of the oils exhibited oviposition deterrent activities against gravid Ae. aegypti females. GC analysis with electroantennographic detection indicated that the oil constituents n-decanol, 2-undecanone, undecanal, dodecanal, trans-caryophyl-lene, (E)-β-farnesene, α-humulene, n-dodecanol, isodaucene and dodecanoic acid were able to trigger antennal depolarization in Ae. aegypti females. Bioassays confirmed that solutions containing 50 ppm of n-dodecanol or dodecanal exhibited oviposition deterrent activities, while a solution containing the alcohol and aldehyde in admixture at concentrations representative of the oil presented an activity similar to that of the 100 ppm oil solution. Docking and molecular dynamics simulations verified that the interaction energies of the long-chain oil components and Ae. aegypti odorant binding protein 1 were quite favorable, indicating that the protein is a possible oviposition deterrent receptor in the antenna of Ae. aegypti.
European Journal of Medicinal Chemistry, 2015
A set of aryl-and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologic... more A set of aryl-and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologically evaluated against the larvae of Aedes aegypti (A. aegypti), the vector responsible for diseases like Dengue and Yellow Fever. (Q)SAR studies were useful for predicting the activities of the compounds not included to create the QSAR model as well as to predict the features of a new compound with improved activity. Docking studies corroborated experimental evidence of AeSCP-2 as a potential target able to explain the larvicidal properties of its compounds. The trend observed between the in silico Docking scores and the in vitro pLC50 (equals Àlog LC50, at molar concentration) data indicated that the highest larvicidal compounds, or the compounds with the highest values for pLC50, are usually those with the higher docking scores (i.e., greater in silico affinity for the AeSCP-2 target). Determination of cytotoxicity for these compounds in mammal cells demonstrated that the top larvicide compounds are non-toxic.
Bioresource Technology, 2009
The essential oils of leaves, stems and inflorescences of Piper marginatum, harvested in the Atla... more The essential oils of leaves, stems and inflorescences of Piper marginatum, harvested in the Atlantic forest in the State of Pernambuco, Brazil, were obtained by hydrodistillation. GC and GC-MS analyses revealed the presence of 40 components accounting, respectively, for 99.6%, 99.7% and 99.1% of the leaf, stem and inflorescence oil, the most abundant being (Z)-or (E)-asarone and patchouli alcohol. The essential oil of the inflorescences exhibited potent activity against the 4th instar of Aedes aegypti with LC 10 and LC 50 values of 13.8 and 20.0 ppm, respectively. Furthermore, the inflorescence oil did not interfere in the oviposition of A. aegypti females when assayed at 50 ppm. These properties suggest that P. marginatum oil is a potential source of valuable larvicidal compounds for direct use or in conjunction with baits in traps constructed to capture eggs and larvae.
Bioorganic & Medicinal Chemistry, 2013
The mosquito Aedes aegypti is the vector agent responsible for the transmission of yellow fever a... more The mosquito Aedes aegypti is the vector agent responsible for the transmission of yellow fever and dengue fever viruses to over 80 million people in tropical and subtropical regions of the world. Exhaustive efforts have lead to a vaccine candidate with only 30% effectiveness against the dengue virus and failure to protect patients against the serotype 2. Hence, vector control remains the most viable route to dengue fever control programs. We have synthesized a class of 1,2,4-oxadiazole derivatives whose most biologically active compounds exhibit potent activity against Aedes aegypti larvae (ca. of 15 ppm) and low toxicity in mammals. Exposure to these larvicides results in larvae pigmentation in a manner correlated with the LC 50 measurements. Structural comparisons of the 1,2,4-oxadiazole nucleus against known inhibitors of insect enzymes allowed the identification of 3-hydroxykynurenine transaminase as a potential target for these synthetic larvicides. Molecular docking calculations indicate that 1,2,4-oxadiazole compounds can bind to 3-hydroxykynurenine transaminase with similar conformation and binding energies as its crystallographic inhibitor 4-(2-aminophenyl)-4-oxobutanoic acid.
Parasitology Research
Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essent... more Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L4). Also, the resistance of MuLL to digestion by L4 gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L4 gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L4 with LC50 of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L4 gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference in the activity of digestive larval enzymes.
PLOS ONE, 2015
In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival... more In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution should be used when employing this extract as a larvicidal agent.
Phytochemistry, 2015
Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarka... more Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarkable sexual dimorphism in floral morphology. Flowers of Catasetum produce perfumes as rewards, which are collected only by male euglossine bees. Currently, floral scents are known to be involved in the selective attraction of specific euglossine species. However, sexual dimorphism in floral scent and its eventual role in the pollination of Catasetum species have never been investigated. Here, we have investigated the pollination of Catasetum uncatum and asked: (1) Is floral scent a sexual dimorphic trait? (2) Does pollinarium removal/deposition affect scent emission? (3) Does sexual dimorphism in floral scent and changed scent emission have implications with regard to the behaviour of the pollinators? The frequency and behaviour of floral visitors were observed in non-manipulated flowers (both flower sexes) and in manipulated flowers (pistillate only) in which pollinaria were deposited. Scents of staminate and pistillate flowers (both manipulated and non-manipulated) were collected by using dynamic headspace methods and analysed chemically. Electrophysiological analyses were performed to detect compounds triggering antennal depolarisation in the euglossine species. C. uncatum is pollinated mainly by males of Euglossa nanomelanotricha. Pollinators were more frequent in pistillate than in staminate inflorescences. Bees approaching staminate flowers frequently flew away without visiting them, a behavioural pattern not observed in pistillate flowers. In the chemical analyses, we recorded 99 compounds, 31 of which triggered antennal depolarisation in pollinators. Multivariate analyses with the electrophysiological-active compounds did not detect differences between the scent composition of staminate and pistillate flowers. Pollinarium removal or deposition resulted in diminished scent emission within 24 h in staminate and pistillate flowers, respectively. Surprisingly, bees discriminated pollinated from non-pollinated pistillate flowers as early as 2 h after pollination. The rapid loss in the attractiveness of flowers following pollinarium removal/deposition can be interpreted as a strategy to direct pollinators to nonpollinated flowers. We have found no evidence that euglossine males discriminate staminate from pistillate flowers by means of floral scent. Instead, we speculate that bees use visual cues, such as sex dimorphic traits, to discriminate flowers of different sexes. Together, our results provide interesting insights into the evolution of floral signals in gender-dimorphic species and into its significance in plant reproductive biology.
Proceedings of the 15th Brazilian Meeting on Organic Synthesis Proceedings, 2013
Revista Brasileira de Fruticultura, 2003
... DE FRUTOS DO ABACAXI1 ADRIANA GUIMARÃES DUARTE2, IVANILDO SOARES DE LIMA3, DANIELA MARIA DO A... more ... DE FRUTOS DO ABACAXI1 ADRIANA GUIMARÃES DUARTE2, IVANILDO SOARES DE LIMA3, DANIELA MARIA DO AMARAL FERRAZ NAVARRO4, ANTÔNIO EUZÉBIO GOULART SANT'ANA5 RESUMO O objetivo deste ...
Química Nova, 2002
... Ruth Rufino do Nascimento e Antônio Euzébio Goulart Sant'Ana* Departamento de Química/CC... more ... Ruth Rufino do Nascimento e Antônio Euzébio Goulart Sant'Ana* Departamento de Química/CCEN Universidade Federal de Alagoas, 57072-970, Maceió - AL ... Ferreira, JMS; Warwick, DRN; Siqueira, LA; Cultura do Coqueiro no Brasil; EMBRAPA-SPI; Aracaju, 1994; p. ...
Phytochemistry, 2014
Night-blooming water lilies are characterized by intense emission of floral VOCs. Their unique sc... more Night-blooming water lilies are characterized by intense emission of floral VOCs. Their unique scent-oriented pollinators, cyclocephaline scarabs (Scarabaeidae, Cyclocephalini), are attracted to flowers that they use as reliable sources of food and as mating aggregation sites. Chemical analysis of floral scent samples of seven species of Nymphaea subg. Hydrocallis established remarkably simple fragrant blends, each of which was dominated by one or two prominent compounds that alone accounted for over 95% of total scent emission. A total of 22 VOCs were identified: aliphatics (9), C5-branched chain compounds (5) and aromatics (8). Anisole was the dominant constituent in the floral scents of Nymphaea amazonum subsp. amazonum, N. amazonum subsp. pedersenii and N. tenerinervia, whereas (methoxymethyl)benzene was the most abundant VOC in samples of N. lasiophylla and N. lingulata. Flowers of N. rudgeana and N. gardneriana emitted high amounts of methyl hexanoate and methyl 2-methylbutanoate. Comparisons of floral VOC composition including other day-and night-blooming species of Nymphaea and Victoria obtained from the literature evidenced disparities related to habitus. While flowers of day-blooming species mostly emit aromatic alcohols and ethers, nocturnal species are particularly rich in aromatic ethers, aliphatic esters and C5-branched chain esters. These findings strongly suggest that the floral scent composition within closely related Nymphaea and Victoria is linked to pollinator selection, and the putative role of floral VOCs in pollinator attractiveness is discussed.
Journal of Crustacean Biology, 2013
Success in rearing fish depends on the nutritional content of food offered to the larvae. The aim... more Success in rearing fish depends on the nutritional content of food offered to the larvae. The aim of this study was to test the effect of diets on fatty acid composition of the copepod Tisbe biminiensis Volkmann-Rocco, 1973 as a food source. The copepods were reared in 5 l vessels with aeration at 29-31°C, salinity 30-35, and natural photoperiod of 13 hours light/11 hours dark. The copepods were fed two diets: a mixture of microalgae Thalassiosira weissflogii and commercial fish food, and only the fish food. Lipids were extracted with chloroform and methanol and esterified by acid catalysis with BF 3 . Three replicates were used in each treatment. Fatty acids were identified by comparison of retention times and co-injection with standard Mix C4-C24 using GC and GCMS apparatus. Thirty-one and 29 fatty acids were detected on copepods fed mixed diets and fish food, respectively. The most abundant fatty acids in copepod fed mixed a diet were C18, C16, and C12. In the other treatment, predominant fatty acids were C18, C16, and C20:2. Thirty-one and 30 fatty acids were detected in the fish food and the microalgae, respectively. The predominant fatty acids of microalgae were C18, C21, and C20:2. For fish food, the predominant fatty acids were C16, C18, and C18:1n9. Essential fatty acids were detected and EPA and DHA contents of copepods fed mixture were significantly higher compared to those fed only ration, indicating that the mixed diet provided better source of HUFA for T. biminiensis. However, its DHA level was lower than other harpacticoid copepods. This suggests that T. biminiensis either needs to be fed a better quality diet, or be enriched with some fatty acids before they are offered to the cobia larvae. The copepod T. biminiensis is capable of bio-converting fatty acid C18:0 into chains with 20 unsaturated carbons. T. biminiensis fed mixed a diet or the fish food alone showed DHA/EPA ratios of 1.3 and 3.3, respectively, suggesting that this copepod species may be suitable for use in fish larviculture.
Evidence-Based Complementary and Alternative Medicine, 2012
Aqueous extract of Indigofera suffruticosa leaves obtained by infusion was used to evaluate the o... more Aqueous extract of Indigofera suffruticosa leaves obtained by infusion was used to evaluate the oviposition, its effect on development of eggs and larvae, and morphological changes in larvae of Aedes aegypti. The bioassays were carried out with aqueous extract in different concentrations on eggs, larvae, and female mosquitoes, and the morphological changes were observed in midgut of larvae. The extract showed repellent activity on A. aegypti mosquitoes, reducing significantly the egg laying by females with control substrate (343 (185-406)) compared with the treated substrate (88 (13-210)). No eclosion of A. aegypti eggs at different concentrations studied was observed. The controlecloded in 35%. At concentration of 250 µg/mL, 93.3% of larvae remained in the second instar of development and at concentrations of 500, 750, and 1000 µg/mL the inhibitory effect was lower with percentages of 20%, 53.3%, and 46.6%, respectively. Morphological changes like disruption on the peritrophic envelope (PE), discontinued underlying epithelium, increased gut lumen, and segments with hypertrophic aspects were observed in anterior region of medium midgut of larvae of A. aegypti. The results showed repellent activity, specific embryotoxicity, and general growth retardation in A. aegypti by medium containing aqueous extract of I. suffruticosa leaves.
Crustaceana, 2013
The present study assessed the efficiency of two transesterification methods for the identificati... more The present study assessed the efficiency of two transesterification methods for the identification of fatty acids in the copepod Tisbe biminiensis Volkmann-Rocco, 1973. In the first method, the samples were esterified by basic catalysis with KOH in methanol, and in the second method they were esterified by acid catalysis with BF 3 . Fatty acids were identified by comparison of retention times and co-injection with standard Mix C4-C24, using gas chromatography and gas chromatography-mass spectrometry. Twenty-nine fatty acids were detected in samples transesterified by basic catalysis or acid catalysis. The predominant fatty acids were C18 (19.18%), C16 (13.02%), and C12 (11.39%) for samples transesterified by acid catalysis; and C13 (25.24%), C21 (11.32%), and C18 (10.65%) for samples transesterified by basic catalysis. The results show that fatty acid analysis for copepods may be affected by the transesterification method. Sample transesterification by acid catalysis was efficient to identify monosaturated and polyunsaturated fatty acids, whereas transesterification by basic catalysis was efficient to identify saturated fatty acids. Essential fatty acids were present in the copepod, which suggests that T. biminiensis is a useful food to be used in larviculture.
Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2009
Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is ... more Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. This report deals with the larvicidal activity of lectins isolated from Myracrodruon urundeuva bark (MuBL) and heartwood (MuHL). The lectins were isolated by ammonium sulphate treatment of crude extracts followed by chromatography on chitin. MuBL and MuHL were evaluated by electrophoresis under native (PAGE) and denaturing conditions (SDS-PAGE). Carbohydrate specificity of lectins was evaluated by hemagglutinating activity (HA) inhibition assay using N-acetyl-Dglucosamine and by affinity chromatography on N-acetyl-D-glucosamine immobilized in agarose gel. Larvicidal activity against A. aegypti was investigated with the extracts, salt fractions and isolated lectins. MuBL and MuHL were characterized by PAGE as basic proteins of molecular masses of 14.0 and 14.4 kDa, respectively. The interaction of lectins with N-acetylglucosamine was detected by inhibition of HA by monosaccharide and lectin adsorptions on N-acetyl-D-glucosamine matrix. All M. urundeuva preparations promoted larvae mortality. LC 16 , LC 50 and LC 84 values of 0.077, 0.125, 0.173 for MuBL and 0.03, 0.04 and 0.05 mg/mL for MuHL were obtained. To our knowledge this is the first report of larvicidal activity of lectins against A. aegypti.
Chemosphere, 2009
and sharing with colleagues.
Bioresource Technology, 2007
Larvicidal activities against Aedes aegypti have been determined in the ethanolic extracts obtain... more Larvicidal activities against Aedes aegypti have been determined in the ethanolic extracts obtained from 51 Brazilian medicinal plants. Eleven of the 84 extracts studied showed significant (LC50 < 100 microg mL(-1)) activities against larvae, with extracts from Annona crassiflora (root bark, LC50 = 0.71 microg mL(-1); root wood, LC50 = 8.94 microg mL(-1)) and Annona glabra (seed, LC50 = 0.06 microg mL(-1)) showing the highest activities. The results obtained should be of value in the search for new natural larvicidal compounds.
Chemoecology, 2014
The South American fruit fly is one of the most destructive polyphagous pests in South America. I... more The South American fruit fly is one of the most destructive polyphagous pests in South America. In this species, males gathered in aggregations emit volatiles that attract females; however, the compounds involved in this task remain unknown. In this study, we investigated the chemical composition of the volatile blend emitted by males aiming to identify the specific compounds within this blend that elicit behavioral responses in conspecific females. For this purpose, we performed chemical and electrophysiological analyses and bioassays. The chemical analyses revealed the presence of 29 compounds in headspace samples of A. fraterculus males, of which six compounds, i.e. a-pinene, limonene, (Z)-3-nonen-1-ol, (E,Z)-3,6-nonadien-1-ol, a-farnesene and (S,S)-(-)-epianastrephin, triggered antennal depolarization in conspecific females. In laboratory bioassays, five out of eight synthetic compounds tested individually elicited more behavioral responses than a hexane control, but only the synthetic mixture composed of all EAD-active compounds triggered behavioral responses in females similar to the responses to the headspace samples of conspecific males. In an experiment under semi-natural conditions, the synthetic mixture was more attractive to females than a hexane control and equally attractive to headspace extracts of males. This study reports the identification of male volatile compounds that act as attractant for A. fraterculus females, which may be useful for the control of this pest in infested orchards.
Dengue fever has spread worldwide and affects millions of people every year in tropical and subtr... more Dengue fever has spread worldwide and affects millions of people every year in tropical and subtropical regions of Africa, Asia, Europe and America. Since there is no effective vaccine against the dengue virus, prevention of disease transmission depends entirely on regulating the vector (Aedes aegypti) or interrupting human-vector contact. The aim of this study was to assess the oviposition deterrent activity of essential oils of three cultivars of torch ginger (Etlingera elatior, Zingiberaceae) against the dengue mosquito. Analysis of the oils by gas chromatography (GC)—mass spectrometry revealed the presence of 43 constituents, of which α-pinene, dodecanal and n-dodecanol were the major components in all cultivars. Solutions containing 100 ppm of the oils exhibited oviposition deterrent activities against gravid Ae. aegypti females. GC analysis with electroantennographic detection indicated that the oil constituents n-decanol, 2-undecanone, undecanal, dodecanal, trans-caryophyl-lene, (E)-β-farnesene, α-humulene, n-dodecanol, isodaucene and dodecanoic acid were able to trigger antennal depolarization in Ae. aegypti females. Bioassays confirmed that solutions containing 50 ppm of n-dodecanol or dodecanal exhibited oviposition deterrent activities, while a solution containing the alcohol and aldehyde in admixture at concentrations representative of the oil presented an activity similar to that of the 100 ppm oil solution. Docking and molecular dynamics simulations verified that the interaction energies of the long-chain oil components and Ae. aegypti odorant binding protein 1 were quite favorable, indicating that the protein is a possible oviposition deterrent receptor in the antenna of Ae. aegypti.
European Journal of Medicinal Chemistry, 2015
A set of aryl-and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologic... more A set of aryl-and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologically evaluated against the larvae of Aedes aegypti (A. aegypti), the vector responsible for diseases like Dengue and Yellow Fever. (Q)SAR studies were useful for predicting the activities of the compounds not included to create the QSAR model as well as to predict the features of a new compound with improved activity. Docking studies corroborated experimental evidence of AeSCP-2 as a potential target able to explain the larvicidal properties of its compounds. The trend observed between the in silico Docking scores and the in vitro pLC50 (equals Àlog LC50, at molar concentration) data indicated that the highest larvicidal compounds, or the compounds with the highest values for pLC50, are usually those with the higher docking scores (i.e., greater in silico affinity for the AeSCP-2 target). Determination of cytotoxicity for these compounds in mammal cells demonstrated that the top larvicide compounds are non-toxic.
Bioresource Technology, 2009
The essential oils of leaves, stems and inflorescences of Piper marginatum, harvested in the Atla... more The essential oils of leaves, stems and inflorescences of Piper marginatum, harvested in the Atlantic forest in the State of Pernambuco, Brazil, were obtained by hydrodistillation. GC and GC-MS analyses revealed the presence of 40 components accounting, respectively, for 99.6%, 99.7% and 99.1% of the leaf, stem and inflorescence oil, the most abundant being (Z)-or (E)-asarone and patchouli alcohol. The essential oil of the inflorescences exhibited potent activity against the 4th instar of Aedes aegypti with LC 10 and LC 50 values of 13.8 and 20.0 ppm, respectively. Furthermore, the inflorescence oil did not interfere in the oviposition of A. aegypti females when assayed at 50 ppm. These properties suggest that P. marginatum oil is a potential source of valuable larvicidal compounds for direct use or in conjunction with baits in traps constructed to capture eggs and larvae.
Bioorganic & Medicinal Chemistry, 2013
The mosquito Aedes aegypti is the vector agent responsible for the transmission of yellow fever a... more The mosquito Aedes aegypti is the vector agent responsible for the transmission of yellow fever and dengue fever viruses to over 80 million people in tropical and subtropical regions of the world. Exhaustive efforts have lead to a vaccine candidate with only 30% effectiveness against the dengue virus and failure to protect patients against the serotype 2. Hence, vector control remains the most viable route to dengue fever control programs. We have synthesized a class of 1,2,4-oxadiazole derivatives whose most biologically active compounds exhibit potent activity against Aedes aegypti larvae (ca. of 15 ppm) and low toxicity in mammals. Exposure to these larvicides results in larvae pigmentation in a manner correlated with the LC 50 measurements. Structural comparisons of the 1,2,4-oxadiazole nucleus against known inhibitors of insect enzymes allowed the identification of 3-hydroxykynurenine transaminase as a potential target for these synthetic larvicides. Molecular docking calculations indicate that 1,2,4-oxadiazole compounds can bind to 3-hydroxykynurenine transaminase with similar conformation and binding energies as its crystallographic inhibitor 4-(2-aminophenyl)-4-oxobutanoic acid.
Parasitology Research
Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essent... more Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L4). Also, the resistance of MuLL to digestion by L4 gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L4 gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L4 with LC50 of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L4 gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference in the activity of digestive larval enzymes.
PLOS ONE, 2015
In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival... more In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution should be used when employing this extract as a larvicidal agent.
Phytochemistry, 2015
Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarka... more Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarkable sexual dimorphism in floral morphology. Flowers of Catasetum produce perfumes as rewards, which are collected only by male euglossine bees. Currently, floral scents are known to be involved in the selective attraction of specific euglossine species. However, sexual dimorphism in floral scent and its eventual role in the pollination of Catasetum species have never been investigated. Here, we have investigated the pollination of Catasetum uncatum and asked: (1) Is floral scent a sexual dimorphic trait? (2) Does pollinarium removal/deposition affect scent emission? (3) Does sexual dimorphism in floral scent and changed scent emission have implications with regard to the behaviour of the pollinators? The frequency and behaviour of floral visitors were observed in non-manipulated flowers (both flower sexes) and in manipulated flowers (pistillate only) in which pollinaria were deposited. Scents of staminate and pistillate flowers (both manipulated and non-manipulated) were collected by using dynamic headspace methods and analysed chemically. Electrophysiological analyses were performed to detect compounds triggering antennal depolarisation in the euglossine species. C. uncatum is pollinated mainly by males of Euglossa nanomelanotricha. Pollinators were more frequent in pistillate than in staminate inflorescences. Bees approaching staminate flowers frequently flew away without visiting them, a behavioural pattern not observed in pistillate flowers. In the chemical analyses, we recorded 99 compounds, 31 of which triggered antennal depolarisation in pollinators. Multivariate analyses with the electrophysiological-active compounds did not detect differences between the scent composition of staminate and pistillate flowers. Pollinarium removal or deposition resulted in diminished scent emission within 24 h in staminate and pistillate flowers, respectively. Surprisingly, bees discriminated pollinated from non-pollinated pistillate flowers as early as 2 h after pollination. The rapid loss in the attractiveness of flowers following pollinarium removal/deposition can be interpreted as a strategy to direct pollinators to nonpollinated flowers. We have found no evidence that euglossine males discriminate staminate from pistillate flowers by means of floral scent. Instead, we speculate that bees use visual cues, such as sex dimorphic traits, to discriminate flowers of different sexes. Together, our results provide interesting insights into the evolution of floral signals in gender-dimorphic species and into its significance in plant reproductive biology.
Proceedings of the 15th Brazilian Meeting on Organic Synthesis Proceedings, 2013
Revista Brasileira de Fruticultura, 2003
... DE FRUTOS DO ABACAXI1 ADRIANA GUIMARÃES DUARTE2, IVANILDO SOARES DE LIMA3, DANIELA MARIA DO A... more ... DE FRUTOS DO ABACAXI1 ADRIANA GUIMARÃES DUARTE2, IVANILDO SOARES DE LIMA3, DANIELA MARIA DO AMARAL FERRAZ NAVARRO4, ANTÔNIO EUZÉBIO GOULART SANT'ANA5 RESUMO O objetivo deste ...
Química Nova, 2002
... Ruth Rufino do Nascimento e Antônio Euzébio Goulart Sant'Ana* Departamento de Química/CC... more ... Ruth Rufino do Nascimento e Antônio Euzébio Goulart Sant'Ana* Departamento de Química/CCEN Universidade Federal de Alagoas, 57072-970, Maceió - AL ... Ferreira, JMS; Warwick, DRN; Siqueira, LA; Cultura do Coqueiro no Brasil; EMBRAPA-SPI; Aracaju, 1994; p. ...
Phytochemistry, 2014
Night-blooming water lilies are characterized by intense emission of floral VOCs. Their unique sc... more Night-blooming water lilies are characterized by intense emission of floral VOCs. Their unique scent-oriented pollinators, cyclocephaline scarabs (Scarabaeidae, Cyclocephalini), are attracted to flowers that they use as reliable sources of food and as mating aggregation sites. Chemical analysis of floral scent samples of seven species of Nymphaea subg. Hydrocallis established remarkably simple fragrant blends, each of which was dominated by one or two prominent compounds that alone accounted for over 95% of total scent emission. A total of 22 VOCs were identified: aliphatics (9), C5-branched chain compounds (5) and aromatics (8). Anisole was the dominant constituent in the floral scents of Nymphaea amazonum subsp. amazonum, N. amazonum subsp. pedersenii and N. tenerinervia, whereas (methoxymethyl)benzene was the most abundant VOC in samples of N. lasiophylla and N. lingulata. Flowers of N. rudgeana and N. gardneriana emitted high amounts of methyl hexanoate and methyl 2-methylbutanoate. Comparisons of floral VOC composition including other day-and night-blooming species of Nymphaea and Victoria obtained from the literature evidenced disparities related to habitus. While flowers of day-blooming species mostly emit aromatic alcohols and ethers, nocturnal species are particularly rich in aromatic ethers, aliphatic esters and C5-branched chain esters. These findings strongly suggest that the floral scent composition within closely related Nymphaea and Victoria is linked to pollinator selection, and the putative role of floral VOCs in pollinator attractiveness is discussed.
Journal of Crustacean Biology, 2013
Success in rearing fish depends on the nutritional content of food offered to the larvae. The aim... more Success in rearing fish depends on the nutritional content of food offered to the larvae. The aim of this study was to test the effect of diets on fatty acid composition of the copepod Tisbe biminiensis Volkmann-Rocco, 1973 as a food source. The copepods were reared in 5 l vessels with aeration at 29-31°C, salinity 30-35, and natural photoperiod of 13 hours light/11 hours dark. The copepods were fed two diets: a mixture of microalgae Thalassiosira weissflogii and commercial fish food, and only the fish food. Lipids were extracted with chloroform and methanol and esterified by acid catalysis with BF 3 . Three replicates were used in each treatment. Fatty acids were identified by comparison of retention times and co-injection with standard Mix C4-C24 using GC and GCMS apparatus. Thirty-one and 29 fatty acids were detected on copepods fed mixed diets and fish food, respectively. The most abundant fatty acids in copepod fed mixed a diet were C18, C16, and C12. In the other treatment, predominant fatty acids were C18, C16, and C20:2. Thirty-one and 30 fatty acids were detected in the fish food and the microalgae, respectively. The predominant fatty acids of microalgae were C18, C21, and C20:2. For fish food, the predominant fatty acids were C16, C18, and C18:1n9. Essential fatty acids were detected and EPA and DHA contents of copepods fed mixture were significantly higher compared to those fed only ration, indicating that the mixed diet provided better source of HUFA for T. biminiensis. However, its DHA level was lower than other harpacticoid copepods. This suggests that T. biminiensis either needs to be fed a better quality diet, or be enriched with some fatty acids before they are offered to the cobia larvae. The copepod T. biminiensis is capable of bio-converting fatty acid C18:0 into chains with 20 unsaturated carbons. T. biminiensis fed mixed a diet or the fish food alone showed DHA/EPA ratios of 1.3 and 3.3, respectively, suggesting that this copepod species may be suitable for use in fish larviculture.
Evidence-Based Complementary and Alternative Medicine, 2012
Aqueous extract of Indigofera suffruticosa leaves obtained by infusion was used to evaluate the o... more Aqueous extract of Indigofera suffruticosa leaves obtained by infusion was used to evaluate the oviposition, its effect on development of eggs and larvae, and morphological changes in larvae of Aedes aegypti. The bioassays were carried out with aqueous extract in different concentrations on eggs, larvae, and female mosquitoes, and the morphological changes were observed in midgut of larvae. The extract showed repellent activity on A. aegypti mosquitoes, reducing significantly the egg laying by females with control substrate (343 (185-406)) compared with the treated substrate (88 (13-210)). No eclosion of A. aegypti eggs at different concentrations studied was observed. The controlecloded in 35%. At concentration of 250 µg/mL, 93.3% of larvae remained in the second instar of development and at concentrations of 500, 750, and 1000 µg/mL the inhibitory effect was lower with percentages of 20%, 53.3%, and 46.6%, respectively. Morphological changes like disruption on the peritrophic envelope (PE), discontinued underlying epithelium, increased gut lumen, and segments with hypertrophic aspects were observed in anterior region of medium midgut of larvae of A. aegypti. The results showed repellent activity, specific embryotoxicity, and general growth retardation in A. aegypti by medium containing aqueous extract of I. suffruticosa leaves.
Crustaceana, 2013
The present study assessed the efficiency of two transesterification methods for the identificati... more The present study assessed the efficiency of two transesterification methods for the identification of fatty acids in the copepod Tisbe biminiensis Volkmann-Rocco, 1973. In the first method, the samples were esterified by basic catalysis with KOH in methanol, and in the second method they were esterified by acid catalysis with BF 3 . Fatty acids were identified by comparison of retention times and co-injection with standard Mix C4-C24, using gas chromatography and gas chromatography-mass spectrometry. Twenty-nine fatty acids were detected in samples transesterified by basic catalysis or acid catalysis. The predominant fatty acids were C18 (19.18%), C16 (13.02%), and C12 (11.39%) for samples transesterified by acid catalysis; and C13 (25.24%), C21 (11.32%), and C18 (10.65%) for samples transesterified by basic catalysis. The results show that fatty acid analysis for copepods may be affected by the transesterification method. Sample transesterification by acid catalysis was efficient to identify monosaturated and polyunsaturated fatty acids, whereas transesterification by basic catalysis was efficient to identify saturated fatty acids. Essential fatty acids were present in the copepod, which suggests that T. biminiensis is a useful food to be used in larviculture.
Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2009
Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is ... more Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. This report deals with the larvicidal activity of lectins isolated from Myracrodruon urundeuva bark (MuBL) and heartwood (MuHL). The lectins were isolated by ammonium sulphate treatment of crude extracts followed by chromatography on chitin. MuBL and MuHL were evaluated by electrophoresis under native (PAGE) and denaturing conditions (SDS-PAGE). Carbohydrate specificity of lectins was evaluated by hemagglutinating activity (HA) inhibition assay using N-acetyl-Dglucosamine and by affinity chromatography on N-acetyl-D-glucosamine immobilized in agarose gel. Larvicidal activity against A. aegypti was investigated with the extracts, salt fractions and isolated lectins. MuBL and MuHL were characterized by PAGE as basic proteins of molecular masses of 14.0 and 14.4 kDa, respectively. The interaction of lectins with N-acetylglucosamine was detected by inhibition of HA by monosaccharide and lectin adsorptions on N-acetyl-D-glucosamine matrix. All M. urundeuva preparations promoted larvae mortality. LC 16 , LC 50 and LC 84 values of 0.077, 0.125, 0.173 for MuBL and 0.03, 0.04 and 0.05 mg/mL for MuHL were obtained. To our knowledge this is the first report of larvicidal activity of lectins against A. aegypti.
Chemosphere, 2009
and sharing with colleagues.
Bioresource Technology, 2007
Larvicidal activities against Aedes aegypti have been determined in the ethanolic extracts obtain... more Larvicidal activities against Aedes aegypti have been determined in the ethanolic extracts obtained from 51 Brazilian medicinal plants. Eleven of the 84 extracts studied showed significant (LC50 < 100 microg mL(-1)) activities against larvae, with extracts from Annona crassiflora (root bark, LC50 = 0.71 microg mL(-1); root wood, LC50 = 8.94 microg mL(-1)) and Annona glabra (seed, LC50 = 0.06 microg mL(-1)) showing the highest activities. The results obtained should be of value in the search for new natural larvicidal compounds.
Chemoecology, 2014
The South American fruit fly is one of the most destructive polyphagous pests in South America. I... more The South American fruit fly is one of the most destructive polyphagous pests in South America. In this species, males gathered in aggregations emit volatiles that attract females; however, the compounds involved in this task remain unknown. In this study, we investigated the chemical composition of the volatile blend emitted by males aiming to identify the specific compounds within this blend that elicit behavioral responses in conspecific females. For this purpose, we performed chemical and electrophysiological analyses and bioassays. The chemical analyses revealed the presence of 29 compounds in headspace samples of A. fraterculus males, of which six compounds, i.e. a-pinene, limonene, (Z)-3-nonen-1-ol, (E,Z)-3,6-nonadien-1-ol, a-farnesene and (S,S)-(-)-epianastrephin, triggered antennal depolarization in conspecific females. In laboratory bioassays, five out of eight synthetic compounds tested individually elicited more behavioral responses than a hexane control, but only the synthetic mixture composed of all EAD-active compounds triggered behavioral responses in females similar to the responses to the headspace samples of conspecific males. In an experiment under semi-natural conditions, the synthetic mixture was more attractive to females than a hexane control and equally attractive to headspace extracts of males. This study reports the identification of male volatile compounds that act as attractant for A. fraterculus females, which may be useful for the control of this pest in infested orchards.