Article

Phytochemistry and larvicidal activity of Spermacoce latifolia Aubl. (Rubiaceae) in the control of Aedes aegypti L. (Culicidae)

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Abstract

In the search for alternative ways to control Aedes aegypti with minimal environmental impact and in a manner that preserves human health, this study sought to evaluate the larvicidal effect of the invasive and antioxidant Spermacoce latifolia plant by performing a phytochemical study. Phytochemical screenings were done according to characterization reactions and thin layer chromatography. Phenolics compounds content (Folin-Ciocalteu's) and flavonoids (AlCl3) spectrophotometric was performed, and the antioxidant activity was determined by the 2,2- diphenyl-1-picrylhydrazyl (DPPH). The phytochemical results revealed the presence of phenolic, flavonoid, tannin, steroid, free triterpene, coumarin, and alkaloid compounds. The content of total phenols (TPs) (482.7 ± 1.8 mg mgGA g-1) and flavonoids (165.4 ± 1.5 mg QE g-1) accounted for the antioxidant activity of 150 μg mL-1 methanolic extract. In the proposed bioassays, groups of 25 third-stage larvae were challenged at different concentrations of plant crude extract (1.0, 0.5, 0.25, and 0.1 mg mL-1) of weight per volume in four replicates. In multiple concentration tests, the concentrations were selected to range from 0 % to 100 % mortality after 24 hours of contact with the solution. Toxicity was defined as the inhibition or total inactivity of the larvae. It was concluded that the methanol extract had an LC50 of 0.625 mg mL-1, indicating its potential use as a larvicide against A. aegypti and linking its activity to its phenolic and flavonoid components. © 2015, Universidade Federal de Uberlandia. All rights reserved.

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... The evaluation of the antioxidant capacity of the essential oils from the leaves of P. amboinicus was performed through the capture method of DPPH radicals (2,2-diphenyl-1picrylhydrazyl) described by Cosmoski et al. (2015) with alterations. It was weighted 0.01 g of the volatile oil diluted in 10 mL of methanol. ...
... The antioxidant capacity of essential oils obtained by the methods of hydro and steam distillation were evaluated according to the capture method of radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH), proposed by Cosmoski et al. (2015). The values of IC 50 for each essential oil are described in Table 3. ...
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In view of the increasing search for natural products with biological activities, such as essential oils are of high quality because of their therapeutic and economic importance and represent the second class of natural compounds with the largest number of active constituents and production through Plants minimizes the environment and sanitary impacts. The objective of the present work is to assess the seasonal effect on the composition and antioxidant activity of essential oil in leaves of Plectranthus amboinicus (Lour.) Spreng using hydro and steam distillation techniques. With regarding to the extraction methodology of essential oils from the P. amboinicus, the hydrodistillation technique is the most efficient in obtaining the volatile product with the best features for the determination of antioxidant activity. The analyses of the essential oil indicated a similarity in their composition, being observed the Carvacrol as major compound in almost all analysis, except in January 2015 using steam distillation extraction. Regarding antioxidant activity and seasonality, it was verified that in October 2014 obtained the best value of inhibitory concentration, with IC50 = 124.97 ppm. However, it was possible to obtain the essential oil from the P. amboinicus leaves through hydro and steam distillation methodologies, but also noted the seasonality influence on it’s the context of antioxidant capacity. © 2017, Universidade Federal de Uberlandia. All rights reserved.
... The species S. latifolia, with a high density of trichomes, was among the least selected by adults of B. tabaci MEAM1 in the free-choice test, although it presented high averages of eggs and nymphs per cm² in the no-choice test. Biochemical studies indicate the occurrence of several secondary compounds in the Rubiaceae plant family, such as phenolic compounds, avonoids, tannins, triterpenes and alkaloids(Cosmoski et al., 2015;Martins & Nunez, 2015), which may be related to changes in colonization behavior and the lower preference of adults of B. tabaci MEAM1 for S. latifolia (a member of the Rubiaceae plant family) in a free-choice test.There are several hypotheses regarding the role of trichomes in the process of host plant selection and colonization by white ies. In one of them, it is suggested that the insect's preference for ovipositing at the base of the trichomes is associated with an adaptive advantage over the attack of natural enemies, as well as a possible favorable microclimate in leaves with high densities of non-glandular trichomes(Butter & Vir, 1989; Chu et al., 1995; Heinz & Zalom, 1995; Torres et al., 2012; Miyazaki et al., 2013). ...
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Being capable of infesting a wide variety of plant species, the whitefly Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) is responsible for severe losses in numerous agricultural crops. In order to increase knowledge regarding interactions involving B. tabaci MEAM1 and plants associated with agricultural landscapes, the present study sought to identify preferential hosts by comparing 15 different common weed species and five cultivated plants (tomato, bell pepper, soybean, maize and cotton) through free and no-choice tests. Additionally, a possible correlation between physical-morphological plant aspects and insect’s colonization behavior was assessed. Positive correlations were verified between the oviposition index and trichome density, and between the number of adults and b* (yellow intensity) index. Negative correlations were observed between the number of adults and L* and a* (luminosity and green intensity, respectively) indexes. In the free choice test, the species Solanum lycopersicum , Senna obtusifolia , Glycine max , Emilia sonchifolia and Euphorbia heterophylla were the most infested during the mean of the evaluation periods, differing from Spermacoce latifolia , Amaranthus viridis and Richardia brasiliensis , which presented the lowest means of insect infestation. In this same test, S. lycopersicum and E. sonchifolia had the greatest oviposition, differing from most of the species. In the no-choice test, E. heterophylla , Galinsoga parviflora and S. latifolia had the highest means of eggs and nymphs per cm². Our results show evidence of the expressive potential of weed species frequently found in Brazilian agricultural fields, such as E. sonchifolia , S. obtusifolia, and E. heterophylla , as alternative hosts of B. tabaci MEAM1.
... These organophosphates usually act directly on the acetylcholinesterase enzyme, causing its accumulation on the synaptic cleft, resulting in hyperexcitability and consequently the insect death (ČOLOVIĆ; KRSTIĆ, 2013;KING;AARON, 2015). Pyrethoids have also been very utilized as an alternate substitute of organophosphates; they are non-cumulative and chemically stable but are toxic to fish, bees and aquatic arthropods (COSMOSKI et al., 2015;MANRIQUE-SAIDE et al., 2015;PORTO et al., 2017). Besides the environmental impact that they cause, another disadvantage of the utilization of chemical insecticides is their high cost as well as the occurrence of resistance in samples of Ae. aegypti populations (ZARA et al., 2016;RODRIGUES et al., 2017). ...
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Several technologies have been developed to control Aedes aegypti, mainly studies on isolated plant molecules. The Schinus terebinthifolius (Raddi) (Anacardiaceae), popularly known as pink pepper is a plant widely used in reforestation of degraded areas and its fruits are used as condiments. The objective of this work was to investigate the potential of essential oils (EOs) and fractions (FRs) obtained from fresh fruits and leaves of S. terebinthifolius. The EOs were obtained by hydrodistillation (2 hours), fractionated on a chromatographic column using as the stationary phase silica gel 60 (0.063-0.2mm), mobile phases: n-hexane, dichloromethane, ethyl acetate and methanol and chemically evaluated by gas chromatography coupled to mass spectrometer (GC/MS). EOs and FRs were tested against larvae of the third stage and pupae of Ae. aegypti by Immersion Test at concentrations ranging from 500.00 to 0.003 mg mL-1 (v/v). The hexane FRs obtained from fruits and leaves were the ones that showed the greatest activity on the larvae (LC99.9= 0.60 mg mL-1 and LC99.9 0.64 mg mL-1, respectively) and pupae (LC99,9 = 2.51 mg mL-1 and 2.61 mg mL-1, respectively). These results were confirmed by the anticholinesterase activity where the hexane (fruit and leaf) FRs presented the highest inhibitory potential on the acetylcholinesterase enzyme (0.156 mg mL-1 and 0.312 mg mL-1, respectively), suggesting the likely mechanism of action. The larvicidal potential can be explained by the presence of the major compounds bicyclogermacrene and germacrene D in the hexane FRs, indicating in this way that they may replace or even act in synergisms with conventional chemical larvicides. In this way the present study opens the field for new researches, aiming the development of products with the compounds bicyclogermacrene and germacrene D, as an alternative in the control of this culicide.
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Introduction: in Brazil, there has been growing interest in the study of medicinal plants in response to recent global trend of concern for biodiversity, based on the idea of sustainable development. Objective: to register and to rescue ethnobotanical, pharmacological and phytochemical species of Rubiaceae family. Methods: the compiled literature covered publications that addressed the use, phytochemistry, and pharmacology of Rubiaceae species in Brazil. Results: a total number of 104 species distributed into 43 genera, mostly used as medicines, has been compiled. A varied range of alkaloids, flavonoids, terpenoids and iridoids, as well as various pharmacological anti-syphilitic, antiasthma, antianemic, antiangiogenic, antiinflammatory, antitumor, and antioxidant properties were registered. Conclusions: there is a lack of specific ethnobotanical studies on the Rubiaceae family and there is a prevalence of chemical and pharmacological studies in the Southeast and the Southern regions of the country.
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A total of 42 ethanolic extracts from 30 different plant species, native to the Pantanal and Cerrado of the West-Central region of Brazil, have been evaluated for their larvicidal activity against Aedes aegypti larvae, the vector of dengue and dengue hemorrhagic fevers. Among the extracts tested, that obtained from the trunk bark of Ocotea velloziana was the most active. Using a bioassay-directed fractionation of this extract, the active constituent was isolated and characterized as the aporphine alkaloid (+)-dicentrine. Its structure was established on the basis of (1)H and (13)C NMR spectra, optical rotation and by comparison with an authentic sample. This is the first report on the larvicidal activity against A. aegypti of this alkaloid. Our results suggest that (+)-dicentrine may be considered as a promising natural mosquito larvicidal agent.
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Methanol extracts of seven Malaysian medicinal plants were screened for antioxidant and nitric oxide inhibitory activities. Antioxidant activity was measured by using FTC, TBA and DPPH free radical scavenging methods and Griess assay was used for the measurement of nitric oxide inhibition in lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma)-treated RAW 264.7 cells. All the extracts showed strong antioxidant activity comparable to or higher than that of alpha-tocopherol, BHT and quercetin in FTC and TBA methods. The extracts from Leea indica and Spermacoce articularis showed strong DPPH free radical scavenging activity comparable with quercetin, BHT and Vit C. Spermacoce exilis showed only moderate activity but other species were weak as compared to the standards. In the Griess assay Lasianthus oblongus, Chasalia chartacea, Hedyotis verticillata, Spermacoce articularis and Leea indica showed strong inhibitory activity on nitric oxide production in LPS and IFN-gamma-induced RAW 264.7 cells. Extracts from Psychotria rostrata and Spermacoce exilis also inhibited NO production but this was due to their cytotoxic effects upon cells during culture.
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Aedes aegypti is the major vector of dengue fever, an endemic disease in Brazil. In an effort to find effective and affordable ways of controlling this mosquito, the larvicidal activities of essential oils from Croton species widely found in northeastern Brazil were analyzed. The essential oils were extracted by steam distillation, and their chemical composition was determined by gas liquid-chromatography coupled with mass spectroscopy. The main components were methyleugenol and alpha-copaene for C. nepetaefolius (LC50 of 84 ppm); alpha-pinene and beta-pinene for C. argyrophyloides (LC50 of 102 ppm); and alpha-pinene, beta-phelandrene, and trans-caryophyllene for C. sonderianus (LC50 of 104 ppm). Croton zenhtneri exhibited higher larvicidal activity with LC50 of 28 ppm, and the main active constituent was identified as anethole, a phenylpropanoid compound.
Substâncias de Origem Vegetal com Atividade Larvicida Contra Aedes aegypti
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Secondary metabolites isolated from Richardia brasiliensis Gomes (Rubiaceae)
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PINTO, D. S.; TOMAZ, A. C. A.; TAVARES, J. F.; TENÓRIO-SOUZA, F. H.; DIAS, C. S.; BRAZ-FILHO, R.; CUNHA, E. V. L. Secondary metabolites isolated from Richardia brasiliensis Gomes (Rubiaceae). Rev. Bras. Farmacogn., Curitiba, v. 18, p. 3, p. 367-372, jul. – set., 2008.
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Substâncias de Origem Vegetal com Atividade Larvicida Contra Aedes aegypti. Revista Virtual de Química
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