Estudo da funcionalidade de espécies comestíveis do semiárido nordestino e estratégias para sua utilização como ingredientes para fins alimentícios

The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

Estudo etnofarmacológico e fitoquímico das espécies medicinais Cleome spinosa Jacq, Pavonia varians Moric e Croton cajucara Benth

In this present work an ethnographic research was performed with 84 native medicinal specimens from the Litoral Norte Riograndense, from which two plants Cleome spinosa Jacq e Pavonia varians Moric were submitted to ethnobotanic, phytochemistry and pharmacologic investigations. Additionally, a phytopharmacological research of the medicinal specimen Croton cajucara Benth ( native plant of the Amazon region of Brazil) was improved. The obtained phytochemical results of the C. spinosa and P. varians showed the presence of flavonoids constituents, among other components. The two flavonoids (2S)-5-hydroxy-7,4 -dimethoxy-flavanone and 5,4 -dihydroxy-3,7,3 -trimethoxy-flavone were isolated from C. spinosa. The antioxidant activity of the hydroalcoholic extracts of C. spinosa and P. varians solubilized in the microemulsion systems SME-1 and SME-4, was evaluated in the DPPHmethod. The used SME systems [obtained with Tween 80: Span 20 (3:1) and isopropyl myristate (IPM)] improved the dissolution of those tested polar extracts, with higher efficacy to the SME-1 system (in which ethanol was included as cosurfactant). The CE50 values evidenced for P. varians were 114 [g/mL (SME-1) and 246 [g/mL (SME-4); for C. spinosa it was 224 [g/mL (SME-1) and 248 [g/mL (SME-4), being the system SME-1 more effective for both tested extracts. The hydroalcoholic extracts of P. varians (HAE-PV) was also submitted to pharmacological screening for antinociceptive activity in animal models. The oral administration of this extract (100, 300 and 1000 mg/kg) inhibited the acetic acid-induced writhing in mice. The higher inhibition (74%) was evidenced to the 1000 mg/kg administered dose. Its effect on the central nervous system (CNS) was investigated by tail flick and formalin-method and reveled that it has negligible antinociceptive action on the CNS. After taking consideration of HAE-PV interaction, Pavonia varians Moric could be used as a potent analgesic agent in case of peripheral algesia, without affecting the CNS. The phytochemical study of the stem bark of Croton cajucara Benth lead to the isolation of 19-nor-clerodanetype diterpenes, as well as to the separation of its fixed oil FO-CC. This non polar oil material reveled to be rich in sesquiterpenes and 19-nor-clerodanes components. The biologic effect of OF-CC was evaluated in the development in vitro of the fungis phytopatogens such as Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii. Significant inhibitory effect of the tested fungis (at 0,2 mg.mL-1 dosage) were comproved. A Mass Spectrometry study of clerodane-type diterpenes was developed in order to identify characteristic fragments on mass spectrometra of both clerodane and 19-nor-clerodane presenting an α,β-insaturated carbonyl moiety at ring A of the decalin-system. For that study, mass spectroscopy data were analysed for 19-nor-clerodanes [trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B (c-CJC-B), and cajucarinolide (CJCR)] and for clerodanes [isosacacarin (ISCR) and transcajucarin A (t-CJC-A)] obtained from the stem bark of C. cajucara, and also clerodane-type from other species. The trans-junction of the enone-system clerodanes was clear correlated with the presence of the characteristic ions at m/z 95, 121 e 205. Meanwhile, the characteristics ions at m/z 122 e 124 were correlated to cis-junction. The trans-junction of the enone-system 19-nor-clerodanes showed characteristics ions at m/z 161, 134 e 121. This study could be successful employed for identification of clerodane constituents from other specimens without any additional spectroscopic analyses, as well as a previously phytochemical analyzes in clerodane project search

Estudo integrado do potencial fitorremediador da Eichhornia crassipes em ambientes naturais e sua utilização para obtenção de extratos proteicos

This study aimed to analyze the phytoremediation potential of Eichhornia crassipes in natural environments, optimize the extraction process of crude protein from plant tissue and, obtain and characterize this process in order to determine its viability of use instead of the protein sources of animal and/or human feed. For this, it has been determined in Apodi/Mossoró river water the concentration of ammonium ions, nitrite, nitrate, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cádmium, lead, and total chromium; It was determined in plant tissue of aquatic macrophytes of Eichhornia crassipes species present in Apodi/Mossoró River the moisture content, ash, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cadmium, lead, total chromium, total nitrogen and crude protein. It was also determined the translocation factor and bioaccumulation of all the quantified elements; It was developed and optimized the extraction procedure of crude protein based on the isoelectric method and a factorial design 24 with repetition; It was extracted and characterized the extract obtained by determining the moisture content, ash, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, cadmium, total nitrogen and crude protein. And finally, it was also characterized the protein extract using Thermogravimetric Analysis (TG), Derived Thermogravimetric (DTG), Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FT-IR) and jelly-like electrophoresis of polyacrylamide (SDS -PAGE) to assess the their molecular weights/mass. Thus, from the results obtained for the translocation and bioaccumulation factors was found that the same can be used as phytoremediation agent in natural environments of all quantified elements. It was also found that the developed method of extraction and protein precipitation was satisfactory for the purpose of the work, which gave the best conditions of extraction and precipitation of proteins as: pH extraction equal to 13.0, extraction temperature equals 60 ° C, reaction time equals to 30 minutes, and pH precipitation equals to 4.0. As for the extract obtained, the total nitrogen and crude protein were quantified higher than those found in the plant, increasing the crude protein content approximately 116.88% in relation to the quantified contente in the vegetal tissue of macrophyte. The levels of nickel and cadmium were the unique that were found below the detection limit of used the equipment. The electrophoretic analysis allowed us to observe that the protein extract obtained is composed of low polypeptide chains by the molecular and phytochelatins, with 6 and 15 kDa bands. Analysis of TG, DTG, DSC and FT-IR showed similarities in protein content of the obtained extracts based on different collection points and 9 parts of the plant under study, as well as commercial soy protein and casein. Finally, based on all these findings, it was concluded that the obtained extract in this work can be used instead of the protein sources of animal feed should, before that, test its digestibility. As human supplementation, it is necessary to conduct more tests associated with the optimization process in the sense of removing undesirable components and constant monitoring of the water body and the raw material used

Potencial de uso dos recursos vegetais em uma comunidade rural do semiárido do Rio Grande do Norte

The aim of the present study was to identify the main plant use categories of native varieties from the Caatinga biome, in the rural community of Caicó, Rio Grande do Norte state (Northeastern Brazil). Semi-structured and structured interviews were used to gather information from local specialists about the use of the plants. The uses of 69 species are described by 23 observers (woodsmen, herb doctors, healers, farmers and housewives) aged 35 years or more. These species were allocated to seven categories: medicinal, wood plants, nutritional, mystic, fuel, forage plants and domestic use. The most represented families were Fabaceae (14 spp.), Euphorbiaceae (6 spp.), Cucurbitaceae (3 spp.) and Cactaceae (3 spp.). The calculation of use- value showed that the cumaru (Amburana cearensis (Allemão) A. C. Sm) and the jurema-preta (Mimosa tenuiflora (Willd.) Poir) were the most commonly mentioned, in addition to having the largest number of uses. The data obtained confirm the potential of the plants from the Seridó region and reinforce the importance of biodiversity for rural communities, underscoring the need for local plant management

Atividades biológicas de extratos salinos de sementes de plantas da caatinga contra Aedes Aegypti e investigação da participação de proteínas bioativas

Dengue fever, currently the most important arbovirus, is transmitted by the bite of the Aedes aegypti mosquito. Given the absence of a prophylactic vaccine, the disease can only be controlled by combating the vector insect. However, increasing reports of resistance and environmental damage caused by insecticides have led to the urgent search for new safer alternatives. Twenty - um plant s eed extracts from the Caatinga were prepared , tested and characterized . Sodium phosphate ( 50 mM pH 8.0) was used as extractor. All extracts showed larvicidal and ovipositional deterrence activity . Extracts of D. grandiflora, E. contortisiliquum, A. cearenses , C. ferrea and C. retusa were able to attract females for posture when in low co ncentration . In the attractive concentrations, the CE of E. contortisiliquum and A. cearenses were able to kill 52% and 100% of the larvae respectively . The extracts of A. cearenses , P. viridiflora, E. velutina, M. urundeuva and S. brasiliensis were also pupicides, while extracts of P. viridiflora, E. velutina, E. contortisiliquum , A. cearenses, A. colubrina, D. grandiflora , B. cheilantha , S. spectabilis, C. pyramidalis, M. regnelli e G. americana displayed adulticidal activity. All extracts were toxic to C. dubia zooplankton . The EB of E. velutina and E. contortisiliquum did not affect the viability of fibroblasts . In all extracts were identified at least two potential insecticidal proteins such as enzyme inhibitors, lectins and chitin - binding proteins and components of secondary metabolism . Considering all bioassays , the extracts from A. cearenses, P. viridiflora, E. contortisiliquum , S. brasiliensis, E. velutina and M. urundeuva were considered the most promising . The E. contortisiliquum extracts was the only one who did not show pupicida activity, indicating that its mechanism of action larvicide and adulticidal is related only to the ingesti on of toxic compounds by insect , so it was selected to be fragmenting. As observed for the CE , th e protein fractions of E. contortisiliquum also showed larvicidal activity, highlighting that F2 showed higher larvicidal activity and lower en vironmental toxicity than the CE source. The reduction in the proteolytic activity of larvae fed with crude extra ct and fractions of E. contortisiliquum suggest ed that the trypsin inhibitors ( ITEc) would be resp onsible for larvicidal activity . However the increase in the purification of this inhibitor resulted in loss of larvicidal activity , but the absence of trypsin inhibitor reduced the effectiveness of the fractions , indicating that the ITEC contributes to the larvicidal activity of this extract. Not been observed larvicidal activity and adulticide in rich fraction vicilin, nor evidence of the contribution o f this molecule for the larvicidal activity of the extract. The results show the potential of seeds from plant extracts of Caatinga as a source of active molecules against insects A. aegypti at different stages of its development cycle, since they are comp osed of different active compounds, including protein nature, which act on different mechanisms should result in the death of insec

Etnobotânica e percepção ambiental de pescadores e coletoras tradicionais submetidos à escassez de recursos vegetais silvestres

In our first chapter was recorded the perception of fishermen and gatherers of Patané about the absence of local forests, was collected a list of species considered locally as strategic use, the ethnoknowledge associated with those, and identify which of these plants are already perceived as scarce in the region. In the second chapter, was studied all species of plants known by the community, the associated knowledge and the various uses. Were used individual interviews, formal and semi-structured, that have been consecutively applied to sampled respondents not probabilistically by snowball. Were collected socioeconomic data of informants. A adequacy test was performed. Guided tours were conducted to gather photographs and samples witnesses of plants, all identified by the usual methods of botany. Excerpts of the interviews on perceptions appear by looking for consensual information. Some data were presented by descriptive statistics. Were mounted two lists of plants, one with the strategic use and one with all the species listed in the study. It was shown that knowledge about plants remains resilient despite the forest resources now no longer be available.

Etnobotânica e percepção ambiental de pescadores e coletoras tradicionais submetidos à escassez de recursos vegetais silvestres

In our first chapter was recorded the perception of fishermen and gatherers of Patané about the absence of local forests, was collected a list of species considered locally as strategic use, the ethnoknowledge associated with those, and identify which of these plants are already perceived as scarce in the region. In the second chapter, was studied all species of plants known by the community, the associated knowledge and the various uses. Were used individual interviews, formal and semi-structured, that have been consecutively applied to sampled respondents not probabilistically by snowball. Were collected socioeconomic data of informants. A adequacy test was performed. Guided tours were conducted to gather photographs and samples witnesses of plants, all identified by the usual methods of botany. Excerpts of the interviews on perceptions appear by looking for consensual information. Some data were presented by descriptive statistics. Were mounted two lists of plants, one with the strategic use and one with all the species listed in the study. It was shown that knowledge about plants remains resilient despite the forest resources now no longer be available.

Atividades anticoagulante e antioxidante de extratos brutos ricos em polissacarídeos sulfatados das macroalgas marinhas marrons Canistrocarpus cervicornis, Dictyota mertensii e Dictyopteris delicatula e de Heterofucanas de Canistrocarpus cervicornis

In the present study, extracts rich-sulfated polysaccharides were obtained from three different species of Dictyotales (a class of brown macroalgae): Canistrocarpus cervicornis, Dictyota mertensii and Dictyopteris delicatula and their anticoagulant and antioxidant activities were evaluated. All extracts showed anticoagulant activity on aPTT assay, but not on PT assay. Extracts also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. The extract from C. cervicornis showed the best results and was choose to have their sulfated polysaccharides fractioned and subsequently analysed. Thus, six fractions (CC-0.3, CC-0.5, CC-0.7, CC-1.0, CC-1.2 and CC-2.0) were obtained by proteolysis followed by sequential acetone precipitation. Agarose gel eletrophoresis stained with blue toluidine, confirmed the presence of sulfated polysaccharides in all fractions. Chemical analyses showed that all fractions presented heterofucans mainly constitued by fucose, galactose, glucuronic acid and sulfate. Any fraction changed the PT. However, all fractions were able to double the aPTT on a dose-dependent manner. CC- 0.3, CC-0.5, CC-0.7 and CC-1.0 needed only 0.100 mg/mL to double the aPTT, result only 1.25 times higher than the Clexane® (0.080 mg/mL), a commercial low molecular heparin. The heterofucans presented appreciable total antioxidant capacity, low capacity on scavenging hydroxyl radical and good efficiency on scavenging superoxide radicals (except CC-1.0). CC-1.2 showed 43.1 % on superoxide radical scavenging. This result was higher than that showed by the same concentration of gallic acid (41.8 %), a known antioxidant. Furthermore, the heterofucans showed excelent activity on ferrous chelating activity (except CC-0.3). CC-0.5, CC-0.7 and CC-1.0 showed the highest activities with 47.0 % of ferrous chelating activity, a result 2.0 times lesser than that exhibited by the same concentration of EDTA. These results clearly indicated the beneficial effects of heterofucans extracted from C. cervicornis as potential anticoagulant and antioxidant agents. However additional steps of purification, structural studies, besides in vivo experiments are needed for these fucans may be used as therapeutic agents

Avaliação das atividades antioxidante, anticoagulante e antiproliferativa de extratos aquosos de marsdenia megalantha

The species of the genus Marsdenia, Apocynaceae, are widely used in folk medicine of several countries. In Brazil is found several species belonging to this genus. The in vitro antioxidant, anticoagulant and antiproliferative activities were evaluated to aqueous extracts of stalk, leaf and root of Marsdenia megalantha. In the total antioxidant capacity assay (expressed as ascorbic acid equivalents) the stalk extract showed 76.0 mg/g, while leaf and root extracts 141.3 mg/g and 57.0 mg/g, respectively. The stalk and leaf extracts showed chelating activity around 40% at 1.5 mg/mL, while root extract, at the same concentration showed, 17%. Only the leaf extract showed a significant ability in superoxide scavenging (80% at 0.8 mg/mL). Any extract was able in scavenge hydroxyl, as well anticoagulant activity. The antiproliferative activity of the extracts was evaluated against HeLa tumor cell line. The extracts inhibited in a dose-dependent manner the cell growth. However, the leaf extract showed 80% of inhibition at 1.0 mg/mL, while stalk and root extracts inhibited 63% and 30%, respectively. To assess the mechanism of cell death caused by the leaf extract in HeLa, was performed flow cytometry and western blot. The results show that leaf extract induces cell death by apoptosis through an activation caspase-independent pathway. These data indicate that stalk and leaf extracts obtained have potential to be used as antioxidants and anticancer drugs

Atividade antioxidante e antiproliferativa de extratos de folhas de Plukenetia volubilis L. (EUPHORBIACEAE)

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Avaliação das atividades antioxidantes e citotóxicas de extratos ricos em polissacarídeos extraídos das hastes de mandacaru (Cereus Jamacaru de Candolle, Cactaceae)

The use of medicinal plants to cure and treat various diseases is a common practice in the world and in Brazil. In several regions of the Brazil´s Northeast, the cactus Cereus jamacaru, known as mandacaru, is used popularly as a treatment to many diseases, including those related to heart respiratory diseases, gastric ulcers, scurvy, and kidney diseases. However, there is a scarcity in the scientific literature that proves scientifically the popular application of this cactus. Like other plants, Cereus jamacaru synthesizes several potentially bioactive molecules, like as polysaccharides. In this work, three polysaccharides-rich aqueous extracts, MCA80, MPM and MCP60, were obtained from this plant and analyzed chemically, as well as their cytotoxic and antioxidant potential. The data showed that all extracts consist mainly of polysaccharides (89.42 to 95.76%), but also protein (> 2%) and phenolic (3 to 8.87%) contaminants were detected. All extracts are rich in galactose, glucose and mannose. In addition, glucuronic acid was found in MCA80 and MCP60. The extracts showed total antioxidant capacity ranged from 55.21 to 68.13 of ascorbic acid equivalents (AAE). Besides, they exhibited reducer power and cupric chelation in a dose-dependent manner. None of the extracts inhibited the MTT reduction in the presence of prostate tumor cells (PC-3). However, MCP60 was the most effective extract by preventing the reduction of MTT by about 80% in the presence of cells 786. Nuclear fragmentation tests showed that this extract induces cell death. The data indicated that mandacaru synthesizes bioactive polysaccharides with potential as antioxidant and antitumor agents. For future studies, it is intended to purify and characterize these polysaccharides and its antioxidant and antitumor mechanisms

Síndromes de polinização ocorrentes em uma área de Mata Atlântica, Paraíba, Brasil

ARAUJO, Afranio Cesar de et al. Síndromes de polinização ocorrentes em uma área de Mata Atlântica, Paraíba, Brasil. Biotemas, Florianopolis, v. 4, n. 22, p.83-94, dez. 2009. Disponível em: . Acesso em: 04 out. 2010.

Purificação e caracterização parcial de uma B-D glicosidade de Artemia franciscana com ação sobre celobiose e lactose

-D-glucosidase (EC 3.2.1.21) is one of the most interesting glycosidases, especially for hydrolysis cellobiose releasing glucose, is last step degradation of cellulose. This function makes the -D-glucosidase is of great interest as a versatile industrial biocatalyst, being critical to various bio-treatment / biorefinery processes, such as bioethanol production. Hen in the report, a -D-glucosidase was extracts from protein extracted of the invertebrate marine Artemia franciscana was purified and characterized with a combination of precipitation with ammonium sulfate (0 - 30%, 30 to 50%, 50 to 80%), the fraction saturated in the range of 30 to 50% (called F-II) was applied in a molecular exclusion chromatography, in Sephacryl S-200, the fractions corresponding to the first peak of activity of -D-glucosidase were gathered and applied in a chromatography of ion exchange in Mono Q; the third peak this protein obtained chromatography, which coincides with the peak of activity of -D-glucosidase was held and applied in a gel filtration chromatography Superose 12 where the first peak protein, which has activity of -D-glucosidase was rechromatography on Superose 12. This enzyme is probably multimerica, consisting of three subunit molecular mass of 52.7 kDa (determined by SDS-PAGE) with native molecular mass of 157 kDa (determined by gel filtration chromatography on Superose 12 under the system FPLC). The enzyme was purified 44.09 times with a recovery of 1.01%. Using up p-nitrophenyl-β-D-glucopiranoside as substrate obtained a Km apparent of 0.229 mM and a Vmax of 1.109 mM.60min-1.mL-1mM. The optimum pH and optimum temperature of catalysis of the synthetic substrate were 5.0 and 45 °C, respectively. The activity of the -D-glucosidase was strongly, inhibited by silver nitrate and N- etylmaleimide, this inhibition indicates the involvement of radical sulfidrila the hydrolysis of synthetic substrate. The -D-glucosidase of Artemia franciscana presented degradativa action on celobiose, lactose and on the synthetic substrate -nitrophenyl-β-D-glucopiranoside indicating potential use of this enzyme in the industry mainly for the production of bioethanol (production of alcohol from the participating cellulose), and production hydrolysate milk (devoid of milk lactose)

Uma Lectina D-lactose específica da esponja marinha Cinachyrella apion: purificação, caracterização e interação com Leishmania chagasi

Four different sponge species were screened using Ouchterlony agarose gel and immunodiffusion tests to identify cross-reactivity with the polyclonal antibody IgG anti-deglicosilated CvL, a lectin from Cliona varians. Crude extract from the sponge Cinachyrella apion showed cross-reactivity and also a strong haemmaglutinating activity towards human erythrocytes of all ABO groups. Thus, it was submitted to acetone fractionation, IgG anti-deglicosilated CvL Sepharose affinity chromatography, and Fast Protein Liquid Chromatography (FPLC-AKTA) gel filtration on a Superose 6 10 300 column to purify a novel lectin. C. apion lectin (CaL) agglutinated all types of human erythrocytes with preference for papainized type A and O erythrocytes. The haemagglutinating activity is independent of Ca2+, Mg2+ and Mn2+ ions, and it was strongly inhibited by the disaccharide D-lactose, up to a minimum concentration of 6.25 mM. CaL molecular mass determined by FPLC-AKTA gel filtration on a Superose 12 10 300 column and SDS gel electrophoresis was approximately 124 kDa, consisting of eight subunits of 15.5 kDa, assembled by hydrophobic interactions. The lectin was relatively heat- and pH-stable. Leishmania chagasi romastigotes were agglutinated by CaL, indicating that lactose receptors could be presented in this parasite stage. These findings are indicative of the physiological defense roles of CaL and its possible use in the antibiosis of pathogenic protozoa

Atividade bioinseticida e mecanismo de ação de vicilinas de sementes Erythrina velutina sobre moscas-das frutas Ceratitis capitata

The fruit fly Ceratitis capitata is considered the most destructive pest of the world fruitculture. Many pest management practices, mainly based on agrochemicals, have been developed to allow the world-wide commerce of fruit. Solutions to decrease the use of synthetic insecticides in agriculture are based on the development of new target-specific compounds which cause less damage to the environment, especially vegetal proteins with insecticidal effects. The aim of this work was to evaluate the deleterious effect of a purified vicilin of E. velutina (EvV) seeds to C. capitata larvae and adult insects and to investigate the mechanisms involved in these effects. EvV was purified, characterized and its deleterious effect was tested in bioassay systems. EvV mechanism of action was determined by immunodetection techniques and fluorescence localization in chitin structures that are present in C. capitata digestory system. EvV is a glycoprotein with affinity to chitin. Its molecular weight, of 216,57 kDa, was determined by gel filtration chromatography in FPLC system. Using SDS-PAGE, it was possible to observe EvV dissociation in two main subunits of 54,8 and 50,8 kDa. When it was submitted to eletrophoresis in native conditions, EvV presented only one band of acid characteristic. The WD50 and LD50 values found in the bioassays were 0,13% and 0,14% (w/w), respectively for the larvae. EvV deleterious effects were related to the binding to chitin structures presented in peritrophic membrane and gut epithelial cells, associated with its low digestibility in C. capitata digestive tract. The results described herein are the first demonstration of the larvicidal effects of plant protein on C. capitata larvae. EvV may be part of the pest management programs, in the toxic bait composition, or an alternative in plant improvement program