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1.
Biosci. j. (Online) ; 36(Supplement1): 238-248, Dec. 2020. tab
Artículo en Inglés | LILACS | ID: biblio-1355253

RESUMEN

Synthetic auxin herbicides constitute major alternatives for managing tough-to-kill weeds such as Ipomoea spp. Adjuvant use is known to positively affect the biological efficacy of pesticides by modifying key spraying solution and droplet properties. Determining to what extent the use of adjuvants could change spray solution parameters and affect synthetic auxin herbicides' efficiency for Ipomoea spp. control were the research goals. The study was conducted in two phases: laboratory and field, respectively. In the laboratory, the pH, the surface tension, and the resources of the herbicide drops were measured. In the field, weed control was evaluated. All adjuvants modified spray solution properties, lowering surface tension values. Most adjuvants decreased pH values as well as number and density of droplets due to an increase in droplet size. Regardless of adjuvant usage, Ipomoea spp. control levels rose more rapidly following 2,4-D spraying rather than dicamba, resulting in lower biomass accumulation when the former was used. Dicamba-containing treatments displayed slightly but significantly lower Ipomoea spp. control levels at the end of the evaluation period. Herbicide efficacy for Ipomoea spp. control was not improved upon the addition to the spray solution of any of the tested adjuvants. Adjuvant use altered spraying solution and droplet properties. 2,4-D spraying allowed for lower Ipomoea spp. biomass and greater control levels relative to dicamba, suggesting it might constitute a better option for Ipomoea spp. control. Even though herbicide efficacy was not improved with adjuvants, their use should still be considered given favorable spraying solution alterations, mainly with some alteration in droplet sizes despite the use of similar spray nozzles tips - maintaining weed control efficacy.


Os herbicidas mimetizadores da auxina constituem alternativas importantes para o manejo de plantas daninhas de difícil controle, como Ipomoea spp. Sabe-se que o uso de adjuvante afeta positivamente a eficácia biológica dos pesticidas, modificando as principais propriedades da solução e do espectro de gotas da pulverização. Os objetivos desse trabalho foram determinar em que medida o uso de adjuvantes pode alterar os parâmetros da solução de pulverização e afetar a eficiência dos herbicidas mimetizadores da auxina para Ipomoea spp. Os estudos foram conduzidos em duas fases: em laboratório e em campo. Em laboratório foi avaliado o pH, tensão superficial e características das gotas dos herbicidas. Em campo foi avaliado o controle da planta daninha. Todos os adjuvantes modificaram as propriedades da solução de pulverização, diminuindo os valores de tensão superficial. A maioria dos adjuvantes diminuiu os valores de pH, bem como o número e a densidade de gotas. Independentemente do uso de adjuvante, os níveis de controle de Ipomoea spp. aumentaram mais rapidamente após a pulverização com 2,4-D do que com o dicamba, resultando em menor acúmulo de biomassa quando o primeiro foi usado. Os tratamentos contendo dicamba apresentaram ligeiramente menor controle de Ipomoea spp. A aplicação de 2,4-D promoveu menor biomassa e maiores níveis de controle em relação ao dicamba de Ipomoea spp., sugerindo que possa constituir uma opção melhor de controle. Embora a eficácia do herbicida não tenha sido melhorada com adjuvantes, seu uso ainda deve ser considerado com alterações favoráveis da solução de pulverização, principalmente tamanhos de gotas em qualquer uso de pontas de pulverização - mantendo a eficácia do controle de plantas daninhas.


Asunto(s)
Reguladores del Crecimiento de las Plantas , Convolvulus , Control de Malezas , Herbicidas
2.
Arab Journal of Pharmaceutical Sciences. 2008; 3 (8): 69-76
en Inglés, Arabe | IMEMR | ID: emr-85801

RESUMEN

Ecbalium elaterium, Convolvulus piosellifollus, Cyperus bulbosus and Echinacea angustifolia were selected for studying their hepatoprotective effects against induced liver toxicity by CCI4 in rats. The extent of liver protection is reflected by measuring the biochemical parameters: serum glutamate oxaloacetate transaminase [SGOT], serum glutamate pyruvate transaminase [SGPT], alkaline phosphatase [ALP] and total bilirubin that indicate the condition of liver cells. Extracts that showed good reduction in the biomarker levels were further subjected for histopathological study to explore the extent of protection of hapatocytes. Only the extract of Ecbalium elaterium was effective in reducing the elevated enzyme levels at the 500 mg/kg dose. However, in the histopathological study the extract failed to restore the normal appearance of hepatocytes. All the results were compared with silymarin, as a reference hepatoprotective drug


Asunto(s)
Masculino , Femenino , Animales de Laboratorio , Convolvulus , Cyperus , Echinacea , Ratas Wistar , Cucurbitaceae , Extractos Vegetales , Tetracloruro de Carbono/toxicidad , Silimarina
3.
J Biosci ; 2003 Feb; 28(1): 121-8
Artículo en Inglés | IMSEAR | ID: sea-110882

RESUMEN

Increasing evidence supports the role of excitotoxicity in neuronal cell injury. Thus, it is extremely important to explore methods to retard or reverse excitotoxic neuronal injury. In this regard, certain dietary compounds are beginning to receive increased attention, in particular those involving phytochemicals found in medicinal plants in alleviating neuronal injury. In the present study, we examined whether medicinal plant extracts protect neurons against excitotoxic lesions induced by kainic acid (KA) in female Swiss albino mice. Mice were anesthetized with ketamine and xylazine (200 mg and 2 mg/kg body wt. respectively) and KA (0.25 microg in a volume of 0.5 microl) was administered to mice by intra hippocampal injections. The results showed an impairment of the hippocampus region of brain after KA injection. The lipid peroxidation and protein carbonyl content were significantly (P < 0.05) increased in comparison to controls. Glutathione peroxidase (GPx) activity (EC 1.11.1.9) and reduced glutathione (GSH) content declined after appearance of excitotoxic lesions. As GPx and GSH represent a major pathway in the cell for metabolizing hydrogen peroxide (H2O2), their depletion would be expected to allow H2O2 to accumulate to toxic levels. Dried ethanolic plant extracts of Withania somnifera (WS), Convolvulus pleuricauas (CP) and Aloe vera (AV) dissolved in distilled water were tested for their total antioxidant activity. The diet was prepared in terms of total antioxidant activity of plant extracts. The iron (Fe3+) reducing activity of plant extracts was also tested and it was found that WS and AV were potent reductants of Fe3+ at pH 5 5. CP had lower Fe3+ reducing activity in comparison to WS and AV. Plant extracts given singly and in combination 3 weeks prior to KA injections resulted in a decrease in neurotoxicity. Measures of lipid peroxidation and protein carbonyl declined. GPx activity and GSH content were elevated in hippocampus supplemented with WS and combination of WS + CP + AV. However, when CP and AV were given alone, the changes in the GPx activity and GSH content were not significant. Although the major factors involved in these properties of phytochemicals remain to be specified, the finding of this study has suggested that phytochemicals present in plant extracts mitigate the effects of excitotoxicity and oxidative damage in hippocampus and this might be accomplished by their antioxidative properties.


Asunto(s)
Aloe/química , Animales , Antioxidantes/farmacología , Convolvulus/química , Etanol/química , Agonistas de Aminoácidos Excitadores/toxicidad , Femenino , Glutatión/efectos de los fármacos , Glutatión Peroxidasa/efectos de los fármacos , Hipocampo/citología , Ácido Kaínico/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Ratones , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Raíces de Plantas/química , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Withania/química
4.
P. R. health sci. j ; 21(4): 323-338, Dec. 2002.
Artículo en Inglés | LILACS | ID: lil-356232

RESUMEN

BACKGROUND: Plant materials represent promising sources of anti-cancer agents. We developed and tested a novel extract from the ubiquitous plant Convolvulus arvensis. MATERIALS AND METHODS: Convolvulus arvensis components were extracted in boiling water, and small molecules were removed by high-pressure filtration. The extract's biological activity was assessed by measuring its effects on S-180 fibrosarcoma growth in Kun Ming mice and on heparin-induced angiogenesis in chick embryos. We also examined the extract's effects on lymphocytes ex vivo and tumor cell growth in vitro. RESULTS: The extract (primarily proteins and polysaccharides) inhibited tumor growth in a dose-dependent fashion when administered orally. At the highest dose tested, 200 mg/kg/day, tumor growth was inhibited by roughly seventy percent. Subcutaneous or intraperitoneal administration at 50 mg/kg/day also inhibited tumor growth by over seventy percent. The extract's acute LD50 in Kun Ming mice was 500 mg/kg/day when injected, indicating that tumor growth inhibition occurred at non-toxic doses. It inhibited angiogenesis in chick embryos, improved lymphocyte survival ex vivo, and enhanced yeast phagocytosis, but did not kill tumor cells in culture. CONCLUSION: High molecular mass extract deserves further study as an anti-cancer agent.


Asunto(s)
Humanos , Convolvulus , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Células Cultivadas , Linfocitos/efectos de los fármacos , Ratones , Peso Molecular , Neoplasias/patología
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