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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Perfil fitoquímico e avaliação da toxicidade da espécie gunnera manicata L. nativa do Rio Grande do Sul

Mariotti, Kristiane de Cássia January 2010 (has links)
Gunnera é um gênero de angiosperma pertencente à família Gunneraceae. O gênero possui aproximadamente 45 espécies, dentre essas G. perpensa L. tem sido utilizada na África, apresentando efeitos relacionados ao ciclo reprodutivo, provavelmente devido ao (Z)-venusol. Decocções dessa planta são utilizadas no tratamento de doenças infecciosas devido à atividade antibacteriana e à antifúngica. O gênero Gunnera é capaz de formar uma complexa associação com a cianobactéria Nostoc puctiforme L. ocorrendo a formação da neurotoxina -Nmetilamino- L-alanina (BMAA) a qual é associada ao aparecimento de um complexo de esclerose/Parkinson/demência. No Rio Grande do Sul, encontra-se a espécie G. manicata L., da qual não constam, na literatura científica, estudos fitoquímicos, farmacológicos e toxicológicos, apesar de ser apreciada ornamentalmente. Tendo em vista esses dados, o presente projeto avaliou o perfil tóxico-farmacológico e fitoquímico de G. manicata. Para os ensaios de toxicidade oral aguda e uterotrófico foi utilizado extrato aquoso de raízes e para as atividades antimicrobiana (disco difusão) e antioxidante (reação com 2,2 difenil-1-picril-hidrazil - DPPH•), bem como para o perfil fitoquímico, foram utilizados extratos metanólicos e aquosos de raízes e folhas. Não foram observados sinais de toxicidade oral aguda, nem atividade sob o sistema reprodutor de ratas. O potencial antimicrobiano resultou em atividade frente à Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes e Candida albicans. A capacidade antioxidante apresentou boa a moderada atividade. Na análise fitoquímica por cromatografia gasosa acoplada a detector de massa (CGEM) e cromatografia líquida associada à espectrometria de massas em tandem (CLEM/ EM) não foram detectados BMAA nem (Z)-venusol. Entretanto, foram identificados ácido gálico e hiperosídeo. Os extratos avaliados demonstraram alto teor de compostos fenólicos totais, apesar da baixa concentração de flavonóides totais. Sendo assim, os resultados obtidos neste trabalho geram perspectivas para novos estudos, tendo em vista à ausência de sinais de toxicidade, o potencial biológico apresentado, a falta de informações sobre G. manicata na literatura científica e a prospecção de espécies bioativas. / The genus Gunnera is a flowering plant belonging to the Gunneraceae family. The genus has about 45 species, among these G. Perpensa which has been used in Africa. It has effects related to the reproductive cycle, probably due to the (Z)- venusol. Decoctions of this plant are used in the treatment of infectious diseases due to antibacterial and antifungal activities. The genus Gunnera forms a complex association with the cyanobacterium Nostoc puctiforme L. resulting in the formation of the neurotoxin -N-methylamino-L-alanine (BMAA), which is associated with the development of a complex sclerosis / Parkinson / dementia. In Southern Brazil is found the specie Gunnera manicata L. on which scientific data about phytochemical, pharmacological and toxicological studies are lacking, despite of being assessed as ornamental plant. So, were investigated the toxico-pharmacological and phytochemical profile of G. manicata. In the oral acute toxicity and in the uterotrophic assays aqueous roots extracts were used. To antimicrobial and antioxidant (2,2- diphenyl-1-picryhydrazyl – DPPH - radical test) activities as well as phytochemical profile, methanol and aqueous extracts of roots and leaves were used. Was not observed neither sings of oral acute toxicity nor activity on the female reproductive system of rats. The antimicrobial potential showed activity against Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes and Candida albicans. Antioxidant capacity presented good to moderate activity. The phytochemical profile analysis was performed by gas chromatography coupled with mass spectrometer (GC-MS) and liquid chromatography coupled with tandem mass spectrometer (LC-MS/MS). BMAA and (Z)-venusol were not found and the samples presented gallic acid and hyperoside. The evaluated extracts showed a high content of total phenolic compounds despite of the low contends of total flavonoids. So, the results obtained in this work open prospects for new studies in view of the absence of signs of toxicity, the biological potential presented, the lack of information about G. manicata the scientific literature and the search for bioactive species.
32

Pharmacological evaluation of antidiarrhoeal and antidiabetic activities of Syzygium Cordatum Hochst. ex C. Krauss

Deliwe, Mzonke. January 2011 (has links)
Syzygium cordatum is a medicinal plant indigenous to South Africa and Mozambique, commonly used to treat stomach aches, diabetes, respiratory problems and tuberculosis. In spite of the folklore use, adequate scientific data to credit its widespread traditional use is lacking. The objectives of this study were: to evaluate and validate scientifically the successful therapeutic claims by traditional medicine practitioners that Syzygium cordatum is effective in treating diarrhoea and diabetes / to determine the effects of the plant extract on gastrointestinal transit of a charcoal meal in mice / to determine the effects on castor oilinduced intestinal fluid accumulation / to determine the safety profile of the plant by carrying out acute toxicology study and to carry out preliminary screening of the active compounds present in the plant using standard phytochemical analytical procedures. The aqueous leaf extract of Syzygium cordatum (3.125 -50mg/kg, p.o) significantly reduced the faecal output caused by castor oil (0.7ml). All the doses used, reduced faecal output from 100% produced by castor oil to between 40 and 61%. S.cordatum (6.25 &ndash / 50mg/kg, p.o) significantly and in a dose dependent manner, delayed the onset of castor oil-induced diarrhoea.
33

Εκτίμηση της οξείας τοξικότητας των αποβλήτων μονάδων παραγωγής χάρτου με την χρήση ως βιοδεικτών της πέστροφας Oncorhynchus mykiss και των μακροασπόνδυλων Daphnia pulex και Thamnocephalus platyurus. / Acute toxicity assessment of wastewaters from paper mills with use of the bioindicators: rainbow trout (Oncorhynchus mykiss)and the macroinvertebrates Daphnia pulex and Thamnocephalus platyurus.

Βενετσανέας, Νικόλαος 28 June 2007 (has links)
Στην Ελλάδα γενικά, αλλά και στο Νομό Αχαΐας ειδικότερα, υπάρχουν αρκετές μονάδες παραγωγής χάρτου. Αρκετές από αυτές δεν βρίσκονται εντός των ορίων Βιομηχανικών Περιοχών (ΒΙ.ΠΕ.), με συνέπεια τα ακατέργαστα απόβλητά τους να συμβάλλουν σημαντικά στη ρύπανση του περιβάλλοντος. Το μεγαλύτερο περιβαλλοντικό πρόβλημα που προκαλείται από τις συγκεκριμένες μονάδες είναι η εναπόθεση μεγάλων ποσοτήτων υγρών ακατέργαστων αποβλήτων κυρίως στα υδάτινα οικοσυστήματα. Τα απόβλητα αυτά περιέχουν μεγάλο οργανικό φορτίο, οργανοαλογονωμένες ενώσεις, υψηλά επίπεδα αιωρούμενων στερεών , φαινολών και λιγνινών, με αποτέλεσμα να προκαλούν δυσμενείς επιπτώσεις στους υδάτινους αποδέκτες, όπως τοξικότητα στους υδρόβιους οργανισμούς, ευτροφισμό και άνοδο της θερμοκρασίας. Η παρούσα μελέτη έχει ως βασικό σκοπό την εκτίμηση της τοξικότητας των αποβλήτων δυο μονάδων παραγωγής χάρτου, εγκατεστημένων στην ΒΙ.ΠΕ. Πατρών, με τη χρήση βιοδεικτών. Ως βιοδείκτες χρησιμοποιήθηκαν τόσο ψάρια του γλυκού νερού (πέστροφες του είδους Oncorhynchus mykiss), όσο και μακροασπόνδυλα (των ειδών Daphnia pulex και Thamnocephalus platyurus) με τη μορφή των μικροβιοτέστ Thamnotoxkit F και Daphtoxkit FTM pulex. Συνολικά ελήφθησαν 16 δείγματα (τέσσερα διπλά δείγματα από την κάθε μονάδα). Στα τεστ τοξικότητας που εφαρμόστηκαν (Thamnotoxkit F, Daphtoxkit FTM pulex και πέστροφες), υπολογίσθηκαν τα L(Ε)C50 24h, 48h και 96h αντίστοιχα σύμφωνα με τα πρωτόκολλα εργασίας. Για το μικροβιοτέστ Thamnotoxkit F, τα απόβλητα και από τις δυο μονάδες δεν ήταν τοξικά. Μετά από την μετατροπή των τιμών αυτών σε τοξικές μονάδες, ευρέθη ότι στο Daphtoxkit FTM pulex κυμαίνονταν από 0,79 εώς 1,12 για την ΜΠΧ1 και 1,21 έως 1,38 για την ΜΠΧ2, ενώ στις πέστροφες μεταξύ 2,92 και 4,85 για την ΜΠΧ2. Τα απόβλητα της ΜΠΧ1 δεν ήταν τοξικά για την πέστροφα. Οι τιμές αυτές και για τους τρεις ελέγχους κατατάσσουν τα απόβλητα ως «τοξικά», εκτός από το δείγμα Β της ΜΠΧ1 που ταξινομείται ως «ελαφρά τοξικό». Τα προαναφερθέντα αποδεικνύουν ότι η μονάδα παραγωγής χάρτου με πρώτη ύλη ανακυκλωμένο χαρτί (ΜΠΧ2) είναι σε κάθε περίπτωση πιο τοξική από εκείνη που παράγει χαρτί από καθαρό χαρτοπολτό (ΜΠΧ1). Τέλος, θα πρέπει να σημειωθεί ότι η παρούσα μελέτη είναι η πρώτη μελέτη εκτίμησης της τοξικότητας με βιοδείκτες των αποβλήτων μονάδων παραγωγής χάρτου που γίνεται στη χώρα μας, παρ’ ότι αυτά συμμετέχουν στην επιβάρυνση του περιβάλλοντος. Εκτιμάται ότι τα στοιχεία τοξικότητας που παρατίθενται στη παρούσα εργασία θα είναι χρήσιμα τόσο για την εκπόνηση διαχειριστικών μοντέλων, όσο και μοντέλων εκτίμησης της επικινδυνότητάς τους (risk assessment). / In Greece in general and subsequently in the Achaias Prefecture, several units of paper production exist. Many of them are not located in Industrial Areas and so they contribute significantly to the environmental pollution. The most adverse environmental problem caused by these manufacturing units, is considered to be the release of large quantities of raw liquid effluents, mainly into the aquatic ecosystems. These wastes contain a high organic load, chlorinated compounds (AOCl), high levels of suspended solids, as well as phenols and lignins resulting in hazardous effects on aquatic receivers, like toxicity and eutrophication. In this study, the toxicity of the wastewaters from two paper mills (PM1 and PM2) located in Achaias prefecture is estimated, firstly by using macroinvertebrates (Daphnia pulex και Thamnocephalus platyurus) in the form of microbiotests Thamnotoxkit F and Daphtoxkit FTM pulex, and secondly by using the trout (Onchorynchus mykiss) as a test organism. Sixteen samples were collected from both units overall (four duplicated samples from each mill). In the toxicity tests Thamnotoxkit F, Daphtoxkit FTM pulex and trout, the L(E)C50 in 24, 48 and 96 hours respectively were calculated according to the protocols. Thamnotoxkit F showed no sensitivity for the wastewaters from both mills. After the transformation of these values in toxic units, for Daphtoxkit FTM pulex ranged from 0,79 - 1,12 for PM1 and 1,21 - 1,38 for PM2. In the trout bioassay they varied from 2,92 - 4,85 for PM2, while the values for PM1 were zero. These values classify the tested paper mill effluents as “toxic”, except sample B from PM1 which was classified as “slightly toxic”. Therefore, it is shown that the paper mill which uses recycled paper as primary raw material (PM2) has more toxic waste for the environment than the paper mill which uses pre-treated paper pulp (PM1). Finally, it must be noted that the present study is the first toxicity evaluation study with bioindicators for paper mill wastewaters in our country, even though they contribute significantly to the environmental pollution. It is estimated that the measured toxicity parameters in the present study will be very useful for the designing of management plans, as well as for risk assessment models.
34

Pharmacological evaluation of antidiarrhoeal and antidiabetic activities of Syzygium Cordatum Hochst. ex C. Krauss

Deliwe, Mzonke. January 2011 (has links)
Syzygium cordatum is a medicinal plant indigenous to South Africa and Mozambique, commonly used to treat stomach aches, diabetes, respiratory problems and tuberculosis. In spite of the folklore use, adequate scientific data to credit its widespread traditional use is lacking. The objectives of this study were: to evaluate and validate scientifically the successful therapeutic claims by traditional medicine practitioners that Syzygium cordatum is effective in treating diarrhoea and diabetes / to determine the effects of the plant extract on gastrointestinal transit of a charcoal meal in mice / to determine the effects on castor oilinduced intestinal fluid accumulation / to determine the safety profile of the plant by carrying out acute toxicology study and to carry out preliminary screening of the active compounds present in the plant using standard phytochemical analytical procedures. The aqueous leaf extract of Syzygium cordatum (3.125 -50mg/kg, p.o) significantly reduced the faecal output caused by castor oil (0.7ml). All the doses used, reduced faecal output from 100% produced by castor oil to between 40 and 61%. S.cordatum (6.25 &ndash / 50mg/kg, p.o) significantly and in a dose dependent manner, delayed the onset of castor oil-induced diarrhoea.
35

Avaliação da toxicidade aguda do lixiviado tratado pelos processos de wetland e nanofiltração. / The acute toxicity of the leachate treated by wetland assessment and nanofiltration processes.

Lays Rodrigues Santos de Oliveira 29 April 2014 (has links)
No Brasil, o tratamento do lixiviado, proveniente da disposição dos resíduos sólidos urbanos, ainda é um desafio, haja visto que atualmente não há indícios de tratamento economicamente viável que atenda aos padrões de lançamento da legislação brasileira. Além disso, os diversos tipos de efluentes, mesmo quando adequadamente tratados, apresentam níveis residuais de substâncias que podem conferir toxicidade aos mesmos. Devido a isso, tem-se uma preocupação com essas substâncias remanescentes e, sobretudo, com o seu possível potencial tóxico. Diante desse quadro, a incorporação da avaliação da toxicidade no tratamento dos efluentes é de grande importância na proteção dos ambientes aquáticos. É crescente o interesse pela toxicidade como um parâmetro de controle, que, contudo, é ainda pouco regulamentada. Este estudo tem como principal objetivo ampliar o conhecimento sobre o tratamento de lixiviados através da avaliação da toxicidade por meio de ensaios ecotoxicológicos. Foi avaliada a toxicidade aguda do lixiviado do Aterro Metropolitano de Jardim Gramacho, em Duque de Caxias RJ após os processos de tratamento por wetland e nanofiltração utilizando-se dois organismosteste de diferentes níveis tróficos (Aliivibrio fischeri e Daphnia similis). Os ensaios de toxicidade aguda com a bactéria Aliivibrio fischeri apresentaram valores de CE50 (%) na faixa de 11,75 a 96,17 para o afluente do wetland e valores de CE50 (%) na faixa de 21,60 a 86,32 para o efluente do wetland. Tanto para o afluente, quanto para o efluente do wetland, foram obtidos valores de FT ≤ 8. Para o efluente da nanofiltração, dos 6 ensaios de toxicidade aguda com a bactéria Aliivibrio fischeri, com exceção de 1 amostra, não foi observada toxicidade. Para os ensaios de toxicidade com a Daphnia similis foram obtidos valores de CE50 (%) na faixa de 24,15 a 70,71 para o afluente do wetland e valores na faixa de 19,61 a 70,71 para o efluente do wetland. / In Brazil, treatment of leachate from the disposal of municipal solid waste is still a challenge, since there is currently no evidence of viable treatment that meets the discharge standards of the Brazilian legislation. In addition, the various types of waste, even when treated, have residual levels of substances that can confer toxicity to them. Because of this, there is a concern with these remaining substances, and especially, with its potential toxic possible. Given this situation, the incorporation of evaluation of toxicity in the treatment of effluents is of great importance in protecting aquatic environments. A growing interest in toxicity as a control parameter, which, however, is still largely unregulated. This study aims to increase knowledge about the treatment of leachate through the evaluation of toxicity by ecotoxicological tests. The acute toxicity of the leachate from the Metropolitan Landfill of Jardim Gramacho in Duque de Caxias was evaluated - RJ after treatment processes for wetland and nanofiltration using two test organisms of different trophic levels (Aliivibrio fischeri and Daphnia similis). The acute toxicity tests with Aliivibrio fischeri showed EC50 (%) values in the range from 11.75 to 96.17 to the tributary of the wetland and EC50 (%) values in the range from 21.60 to 86.32 for the effluent wetland. For both the affluent and effluent wetland values were obtained FT ≤ 8. For the effluent from the nanofiltration, the six acute toxicity tests with bacteria Aliivibrio fischeri, except for one sample, no toxicity was observed. For toxicity tests with Daphnia similis were obtained EC50 (%) values in the range from 24.15 to 70.71 for the affluent and wetland values ranging from 19.61 to 70.71 to the effluent of the wetland.
36

Perfil fitoquímico e avaliação da toxicidade da espécie gunnera manicata L. nativa do Rio Grande do Sul

Mariotti, Kristiane de Cássia January 2010 (has links)
Gunnera é um gênero de angiosperma pertencente à família Gunneraceae. O gênero possui aproximadamente 45 espécies, dentre essas G. perpensa L. tem sido utilizada na África, apresentando efeitos relacionados ao ciclo reprodutivo, provavelmente devido ao (Z)-venusol. Decocções dessa planta são utilizadas no tratamento de doenças infecciosas devido à atividade antibacteriana e à antifúngica. O gênero Gunnera é capaz de formar uma complexa associação com a cianobactéria Nostoc puctiforme L. ocorrendo a formação da neurotoxina -Nmetilamino- L-alanina (BMAA) a qual é associada ao aparecimento de um complexo de esclerose/Parkinson/demência. No Rio Grande do Sul, encontra-se a espécie G. manicata L., da qual não constam, na literatura científica, estudos fitoquímicos, farmacológicos e toxicológicos, apesar de ser apreciada ornamentalmente. Tendo em vista esses dados, o presente projeto avaliou o perfil tóxico-farmacológico e fitoquímico de G. manicata. Para os ensaios de toxicidade oral aguda e uterotrófico foi utilizado extrato aquoso de raízes e para as atividades antimicrobiana (disco difusão) e antioxidante (reação com 2,2 difenil-1-picril-hidrazil - DPPH•), bem como para o perfil fitoquímico, foram utilizados extratos metanólicos e aquosos de raízes e folhas. Não foram observados sinais de toxicidade oral aguda, nem atividade sob o sistema reprodutor de ratas. O potencial antimicrobiano resultou em atividade frente à Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes e Candida albicans. A capacidade antioxidante apresentou boa a moderada atividade. Na análise fitoquímica por cromatografia gasosa acoplada a detector de massa (CGEM) e cromatografia líquida associada à espectrometria de massas em tandem (CLEM/ EM) não foram detectados BMAA nem (Z)-venusol. Entretanto, foram identificados ácido gálico e hiperosídeo. Os extratos avaliados demonstraram alto teor de compostos fenólicos totais, apesar da baixa concentração de flavonóides totais. Sendo assim, os resultados obtidos neste trabalho geram perspectivas para novos estudos, tendo em vista à ausência de sinais de toxicidade, o potencial biológico apresentado, a falta de informações sobre G. manicata na literatura científica e a prospecção de espécies bioativas. / The genus Gunnera is a flowering plant belonging to the Gunneraceae family. The genus has about 45 species, among these G. Perpensa which has been used in Africa. It has effects related to the reproductive cycle, probably due to the (Z)- venusol. Decoctions of this plant are used in the treatment of infectious diseases due to antibacterial and antifungal activities. The genus Gunnera forms a complex association with the cyanobacterium Nostoc puctiforme L. resulting in the formation of the neurotoxin -N-methylamino-L-alanine (BMAA), which is associated with the development of a complex sclerosis / Parkinson / dementia. In Southern Brazil is found the specie Gunnera manicata L. on which scientific data about phytochemical, pharmacological and toxicological studies are lacking, despite of being assessed as ornamental plant. So, were investigated the toxico-pharmacological and phytochemical profile of G. manicata. In the oral acute toxicity and in the uterotrophic assays aqueous roots extracts were used. To antimicrobial and antioxidant (2,2- diphenyl-1-picryhydrazyl – DPPH - radical test) activities as well as phytochemical profile, methanol and aqueous extracts of roots and leaves were used. Was not observed neither sings of oral acute toxicity nor activity on the female reproductive system of rats. The antimicrobial potential showed activity against Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes and Candida albicans. Antioxidant capacity presented good to moderate activity. The phytochemical profile analysis was performed by gas chromatography coupled with mass spectrometer (GC-MS) and liquid chromatography coupled with tandem mass spectrometer (LC-MS/MS). BMAA and (Z)-venusol were not found and the samples presented gallic acid and hyperoside. The evaluated extracts showed a high content of total phenolic compounds despite of the low contends of total flavonoids. So, the results obtained in this work open prospects for new studies in view of the absence of signs of toxicity, the biological potential presented, the lack of information about G. manicata the scientific literature and the search for bioactive species.
37

Perfil fitoquímico e avaliação da toxicidade da espécie gunnera manicata L. nativa do Rio Grande do Sul

Mariotti, Kristiane de Cássia January 2010 (has links)
Gunnera é um gênero de angiosperma pertencente à família Gunneraceae. O gênero possui aproximadamente 45 espécies, dentre essas G. perpensa L. tem sido utilizada na África, apresentando efeitos relacionados ao ciclo reprodutivo, provavelmente devido ao (Z)-venusol. Decocções dessa planta são utilizadas no tratamento de doenças infecciosas devido à atividade antibacteriana e à antifúngica. O gênero Gunnera é capaz de formar uma complexa associação com a cianobactéria Nostoc puctiforme L. ocorrendo a formação da neurotoxina -Nmetilamino- L-alanina (BMAA) a qual é associada ao aparecimento de um complexo de esclerose/Parkinson/demência. No Rio Grande do Sul, encontra-se a espécie G. manicata L., da qual não constam, na literatura científica, estudos fitoquímicos, farmacológicos e toxicológicos, apesar de ser apreciada ornamentalmente. Tendo em vista esses dados, o presente projeto avaliou o perfil tóxico-farmacológico e fitoquímico de G. manicata. Para os ensaios de toxicidade oral aguda e uterotrófico foi utilizado extrato aquoso de raízes e para as atividades antimicrobiana (disco difusão) e antioxidante (reação com 2,2 difenil-1-picril-hidrazil - DPPH•), bem como para o perfil fitoquímico, foram utilizados extratos metanólicos e aquosos de raízes e folhas. Não foram observados sinais de toxicidade oral aguda, nem atividade sob o sistema reprodutor de ratas. O potencial antimicrobiano resultou em atividade frente à Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes e Candida albicans. A capacidade antioxidante apresentou boa a moderada atividade. Na análise fitoquímica por cromatografia gasosa acoplada a detector de massa (CGEM) e cromatografia líquida associada à espectrometria de massas em tandem (CLEM/ EM) não foram detectados BMAA nem (Z)-venusol. Entretanto, foram identificados ácido gálico e hiperosídeo. Os extratos avaliados demonstraram alto teor de compostos fenólicos totais, apesar da baixa concentração de flavonóides totais. Sendo assim, os resultados obtidos neste trabalho geram perspectivas para novos estudos, tendo em vista à ausência de sinais de toxicidade, o potencial biológico apresentado, a falta de informações sobre G. manicata na literatura científica e a prospecção de espécies bioativas. / The genus Gunnera is a flowering plant belonging to the Gunneraceae family. The genus has about 45 species, among these G. Perpensa which has been used in Africa. It has effects related to the reproductive cycle, probably due to the (Z)- venusol. Decoctions of this plant are used in the treatment of infectious diseases due to antibacterial and antifungal activities. The genus Gunnera forms a complex association with the cyanobacterium Nostoc puctiforme L. resulting in the formation of the neurotoxin -N-methylamino-L-alanine (BMAA), which is associated with the development of a complex sclerosis / Parkinson / dementia. In Southern Brazil is found the specie Gunnera manicata L. on which scientific data about phytochemical, pharmacological and toxicological studies are lacking, despite of being assessed as ornamental plant. So, were investigated the toxico-pharmacological and phytochemical profile of G. manicata. In the oral acute toxicity and in the uterotrophic assays aqueous roots extracts were used. To antimicrobial and antioxidant (2,2- diphenyl-1-picryhydrazyl – DPPH - radical test) activities as well as phytochemical profile, methanol and aqueous extracts of roots and leaves were used. Was not observed neither sings of oral acute toxicity nor activity on the female reproductive system of rats. The antimicrobial potential showed activity against Bacillus subtilis, Staphylococus aureus, Streptococcus pyogenes and Candida albicans. Antioxidant capacity presented good to moderate activity. The phytochemical profile analysis was performed by gas chromatography coupled with mass spectrometer (GC-MS) and liquid chromatography coupled with tandem mass spectrometer (LC-MS/MS). BMAA and (Z)-venusol were not found and the samples presented gallic acid and hyperoside. The evaluated extracts showed a high content of total phenolic compounds despite of the low contends of total flavonoids. So, the results obtained in this work open prospects for new studies in view of the absence of signs of toxicity, the biological potential presented, the lack of information about G. manicata the scientific literature and the search for bioactive species.
38

Avalia??o da toxicidade aguda do inseticida metomil e o seu efeito sobre a atividade da acetilcolinesterase do peixe Danio rerio

Santos, Paula Ivani Medeiros dos 05 October 2009 (has links)
Made available in DSpace on 2014-12-17T14:02:00Z (GMT). No. of bitstreams: 1 PaulaIM.pdf: 2175384 bytes, checksum: 7697a3aa18d03cba26e4a0d38dbd3b26 (MD5) Previous issue date: 2009-10-05 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Methomyl (Lannate?) is an insecticide from the carbamate group, frequently used in pest control in various types of crops. This compound works inhibiting the activity of the enzyme acetylcholinesterase. The use of physicochemical and ecotoxicological analysis is the most efficient strategy for the correct characterization and control of residues of metomil. The main objectives of this study were to evaluate the acute toxicity of methomyl in 96 hours of exposure and, through a sublethal assay of 5 hours, to assess its effect on the activity of acetylcholinesterase present in brain and squeletic dorsal muscle of the Danio rerio fish. The results showed that the LC50-96 found to D. rerio was 3.4 mg/L and it was found through the average of four definitive tests. In vitro assays were used to test the inhibitory action of methomyl directly over soluble AChE, extracted from the squeletic dorsal muscle, with maximum inhibition of 68.57% to the insecticide concentrations of 0.2 mg/L. In sublethal tests with D. rerio, inhibitory effect of methomyl was found over the soluble form of AChE in the squeletic dorsal muscle, both in one and five hours of fish exposure to the insecticide. In both period, the average values of inhibition were around 61%. In the same condition, no significant inhibitory effect of methomyl soluble and membrane AChE of the D. rerio was observed in the 0.42, 0.85, 1.70 and 2.50 mg/L concentrations and in both times of fish exposure / O Metomil (Lannate?) ? um inseticida do grupo dos carbamatos utilizado no combate a pragas em diversos tipos de lavouras, sua forma de a??o ? atrav?s da inibi??o da enzima acetilcolinesterase. Para uma caracteriza??o adequada e controle de seus despejos, a estrat?gia mais eficiente ? o uso integrado de an?lises qu?micas, f?sicas e ecotoxicol?gicas. O presente trabalho teve por objetivo avaliar a toxicidade aguda em 96h do metomil, e atrav?s de um ensaio subletal de cinco (5) horas, estimar o seu efeito sobre a atividade da acetilcolinesterase no c?rebro e m?sculo esquel?tico dorsal da esp?cie Danio rerio. Os resultados demonstraram que no Danio rerio o valor da CL-50-96h encontrada foi de 3,40 mg/L, obtida atrav?s da m?dia de quatro testes realizados. Nos ensaios in vitro foi atestada a a??o inibit?ria da metomil diretamente sobre a AChE sol?vel extra?da do m?sculo esquel?tico dorsal do D. rerio com uma inibi??o m?xima de 68,57 % para a concentra??o de 0,2 mg/L do inseticida. Nos testes subletais com D. rerio foi constatado o efeito inibit?rio do metomil sobre a forma sol?vel da AChE de m?sculo esquel?tico dorsal, tanto em uma como em cinco horas de exposi??o do peixe ao inseticida. Em ambos os hor?rios os valores m?dios de inibi??o foram em torno de 61%. Nas mesmas condi??es n?o foi observada inibi??o significativa da atividade da AChE de membrana do m?sculos. N?o foi observado efeito inibit?rio do metomil sobre as AChE sol?vel e de membrana de c?rebro de D. rerio, nas concentra??es 0,42, 0,85, 1,70, 2,50 mg/L e em ambos os hor?rios de exposi??o dos peixes
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Avaliação da toxicidade aguda do lixiviado tratado pelos processos de wetland e nanofiltração. / The acute toxicity of the leachate treated by wetland assessment and nanofiltration processes.

Lays Rodrigues Santos de Oliveira 29 April 2014 (has links)
No Brasil, o tratamento do lixiviado, proveniente da disposição dos resíduos sólidos urbanos, ainda é um desafio, haja visto que atualmente não há indícios de tratamento economicamente viável que atenda aos padrões de lançamento da legislação brasileira. Além disso, os diversos tipos de efluentes, mesmo quando adequadamente tratados, apresentam níveis residuais de substâncias que podem conferir toxicidade aos mesmos. Devido a isso, tem-se uma preocupação com essas substâncias remanescentes e, sobretudo, com o seu possível potencial tóxico. Diante desse quadro, a incorporação da avaliação da toxicidade no tratamento dos efluentes é de grande importância na proteção dos ambientes aquáticos. É crescente o interesse pela toxicidade como um parâmetro de controle, que, contudo, é ainda pouco regulamentada. Este estudo tem como principal objetivo ampliar o conhecimento sobre o tratamento de lixiviados através da avaliação da toxicidade por meio de ensaios ecotoxicológicos. Foi avaliada a toxicidade aguda do lixiviado do Aterro Metropolitano de Jardim Gramacho, em Duque de Caxias RJ após os processos de tratamento por wetland e nanofiltração utilizando-se dois organismosteste de diferentes níveis tróficos (Aliivibrio fischeri e Daphnia similis). Os ensaios de toxicidade aguda com a bactéria Aliivibrio fischeri apresentaram valores de CE50 (%) na faixa de 11,75 a 96,17 para o afluente do wetland e valores de CE50 (%) na faixa de 21,60 a 86,32 para o efluente do wetland. Tanto para o afluente, quanto para o efluente do wetland, foram obtidos valores de FT ≤ 8. Para o efluente da nanofiltração, dos 6 ensaios de toxicidade aguda com a bactéria Aliivibrio fischeri, com exceção de 1 amostra, não foi observada toxicidade. Para os ensaios de toxicidade com a Daphnia similis foram obtidos valores de CE50 (%) na faixa de 24,15 a 70,71 para o afluente do wetland e valores na faixa de 19,61 a 70,71 para o efluente do wetland. / In Brazil, treatment of leachate from the disposal of municipal solid waste is still a challenge, since there is currently no evidence of viable treatment that meets the discharge standards of the Brazilian legislation. In addition, the various types of waste, even when treated, have residual levels of substances that can confer toxicity to them. Because of this, there is a concern with these remaining substances, and especially, with its potential toxic possible. Given this situation, the incorporation of evaluation of toxicity in the treatment of effluents is of great importance in protecting aquatic environments. A growing interest in toxicity as a control parameter, which, however, is still largely unregulated. This study aims to increase knowledge about the treatment of leachate through the evaluation of toxicity by ecotoxicological tests. The acute toxicity of the leachate from the Metropolitan Landfill of Jardim Gramacho in Duque de Caxias was evaluated - RJ after treatment processes for wetland and nanofiltration using two test organisms of different trophic levels (Aliivibrio fischeri and Daphnia similis). The acute toxicity tests with Aliivibrio fischeri showed EC50 (%) values in the range from 11.75 to 96.17 to the tributary of the wetland and EC50 (%) values in the range from 21.60 to 86.32 for the effluent wetland. For both the affluent and effluent wetland values were obtained FT ≤ 8. For the effluent from the nanofiltration, the six acute toxicity tests with bacteria Aliivibrio fischeri, except for one sample, no toxicity was observed. For toxicity tests with Daphnia similis were obtained EC50 (%) values in the range from 24.15 to 70.71 for the affluent and wetland values ranging from 19.61 to 70.71 to the effluent of the wetland.
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Estudo ecotoxicológico de corante têxtil e remediação por Fenton e Fenton-like / Ecotoxicological study of textile dye and Fenton and Fenton-like remediation

Fernandes, Neemias Cintra 18 June 2018 (has links)
Submitted by Ana Caroline Costa (ana_caroline212@hotmail.com) on 2018-11-21T16:41:37Z No. of bitstreams: 2 Tese - Neemias Cintra Fernandes - 2018.pdf: 4113836 bytes, checksum: bff379029847f46880350ed814f5048d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-26T14:06:45Z (GMT) No. of bitstreams: 2 Tese - Neemias Cintra Fernandes - 2018.pdf: 4113836 bytes, checksum: bff379029847f46880350ed814f5048d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-26T14:06:45Z (GMT). No. of bitstreams: 2 Tese - Neemias Cintra Fernandes - 2018.pdf: 4113836 bytes, checksum: bff379029847f46880350ed814f5048d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-06-18 / Azo dyes represent the most important class of textile dyes, being widely used in the pharmaceutical and food industry. These molecules are present in domestic and industrial wastewater, and are resistant to conventional effluent treatment eventually producing more toxic products than the original dyes. Advanced oxidative processes (AOPs) have been implemented in order to decompose or mineralize substances that are difficult to treat, reducing their toxicity and the inherent risks of releasing pollutants into the environment. Objective: To study the ecotoxicity and optimize the operational conditions in the decomposition of textile azo dye DR343 using Fenton and Fenton-like reactions. Method: Oxidative processes were studied using the factorial design Box-Behnken Design (BBD), and the optimization of the reaction conditions was performed by applying the desirability function. The pH of the medium, the reaction time, the concentrations of iron [Fe 2+ ] (Fenton) and [Fe 3+ ] (Fenton-like) as well as the oxidizing agent [H 2 O 2 ] were used as independent variables in the planning. The responses studied were the removal of DR343, the concentration of residual hydrogen peroxide [H 2 O 2residual ] and the mortality of Artemia salina. The toxicity of the untreated dye was evaluated in different organisms (lettuce seeds, Artemia salina and zebrafish embryos). Samples treated under optimal conditions were submitted to the same protocols. Results: The dye removal was in the range of 5.8% to 100%, being affected only by the concentration of catalyst [Fe 2+ /Fe 3+ ] in both processes. On the other hand, the process time had a significant effect on the mortality of A. salina in samples submitted to the Fenton process, which suggests formation of toxic oxidation byproducts at the beginning of the process, followed by the mineralization of the samples. Optimum conditions for the Fenton reaction included [Fe 2+ ] of 0.33 mmol.L -1 and [H 2 O 2 ] of 4.50 mmol.L -1 . Under these conditions, 100% of the dye decomposition was observed in 16.1 minutes. On the other hand, the optimal conditions of the Fenton-like process included [Fe 3 + ] of 0.25 mmol.L -1 and [H 2 O 2 ] of 0.54 mmol.L -1 . Under these conditions total dye decomposition was observed in only 9.2 minutes. No [H 2 O 2residual ] was detected in both optimized processes. No significant phytotoxic effects were observed on the untreated dye dispersions, nor after treatment in both procedures. In the case of the A. salina assays, differences between the two processes were observed. Samples treated by Fenton-like did not show significant toxicity, whereas the Fenton process induced significant mortality for this organism. Samples treated under optimal conditions, from both methods, did not induce lethal or sublethal effects on zebrafish embryos. Total organic carbon reduction of 52.0% and 34.8% was observed for Fenton and Fenton-like, respectively. Conclusion: Both the studied processes can be successfully used to decompose the DR343 dye in water, however, the Fenton reaction, despite obtaining better mineralization rates, produced more toxic by-products when compared to the Fenton-like process. The untreated dye did not show phytotoxicity, nor did it generate significant effects on zebrafish embryos. / Os azo corantes, como o Disperse Red 343 (DR343) representam a mais importante classe de corantes têxteis, além de serem amplamente utilizados na indústria farmacêutica e alimentícia. Presentes em águas residuárias industriais e domésticas, estas moléculas são resistentes aos tratamentos convencionais de efluentes e podem, eventualmente, gerar produtos ainda mais tóxicos que os corantes originais. Os processos oxidativos avançados (POAs) têm sido empregados a fim de aumentar a biodegradabilidade ou mineralizar substâncias de difícil tratamento, reduzindo sua toxicidade e os riscos inerentes ao lançamento de poluentes no meio ambiente. Objetivo: Avaliar a ecotoxicidade e otimizar as condições de decomposição do azo corante têxtil DR343 utilizando reações do tipo Fenton e Fenton-like. Metodologia: Os processos oxidativos foram estudados utilizando planejamento fatorial do tipo Box Behnken Design (BBD), e a otimização das condições de reação foi realizada pela aplicação da função de desejabilidade. O pH do meio, o tempo de reação, as concentrações de ferro [Fe 2+ ] (Fenton) e [Fe 3+ ] (Fenton-like), assim como de agente oxidante [H 2 O 2 ] foram utilizadas como variáveis independentes no planejamento. As respostas estudadas foram a remoção do DR343, a concentração de peróxido de hidrogênio residual [H 2 O 2residual ] e a mortalidade de Artemia salina. A toxicidade do corante não-tratado foi avaliada em diferentes organismos (sementes de alface, Artemia salina e embriões de zebrafish). As amostras tratadas sob condições ótimas foram submetidas aos mesmos protocolos. Resultados: A remoção do azo corante esteve na faixa de 5,8% a 100%, sendo afetada somente pela concentração de catalisador [Fe 2+ /Fe 3+ ] em ambos os processos. Por outro lado, o tempo de processo teve efeito significativo na mortalidade de A. salina em amostras submetidas ao processo Fenton, o que sugere formação de subprodutos de oxidação tóxicos no começo do processo, seguido pela mineralização das amostras. Condições ótimas para a reação de Fenton incluíram [Fe 2+ ] de 0,33 mmol.L -1 e [H 2 O 2 ] de 4,50 mmol.L -1 . Nessas condições, observou-se decomposição de 100% do corante em 16,1 minutos. Por outro lado, as condições ótimas do processo Fenton-like incluíram [Fe 3+ ] de 0,25 mmol.L -1 e [H 2 O 2 ] de 0,54 mmol.L -1 . Sob essas condições observou-se a decomposição total do corante em apenas 9,2 minutos. Não foi detectada [H 2 O 2residual ] em ambos os processos otimizados. Nenhum efeito fitotóxico significativo foi observado nas dispersões do corante não-tratado, tampouco após o tratamento em ambos os processos. No caso dos ensaios com A. salina, observou-se diferenças entre os dois processos. As amostras tratadas por Fenton-like não apresentaram toxicidade significativa, enquanto que o processo Fenton induziu mortalidade significativa para esse organismo. Amostras tratadas sob condições ótimas, oriundas de ambos os métodos, não induziram efeitos letais ou subletais aos embriões e larvas de zebrafish. Foi observada redução de carbono orgânico total de 52,0% e 34,8% para Fenton e Fenton-like, respectivamente. Conclusões: O corante não-tratado não apresentou fitotoxicidade, assim como não gerou efeitos tóxicos significativos nos embriões de zebrafish. Ambos os processos estudados podem ser utilizados com sucesso para decompor o corante DR343 em água, entretanto, a reação de Fenton, apesar de obter melhores índices de mineralização, produziu subprodutos mais tóxicos quando comparado ao processo Fenton-like.

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