21,860 research outputs found
MANNAN PRECIPITATION FROM ALOE VERA LEAF PULP JUICE USING METHANOL AND ISOPROPYL ALCOHOL AS ANTI-SOLVENT: EXPERIMENTAL AND EMPIRICAL MODELLING APPROACH
No full textPrecipitation of mannan from Aloe vera leaf pulp juice was investigated using anti-solvent precipitation process under room temperature condition. The aims of this work were to study the effects of types (methanol and isopropyl alcohol) and amount of anti-solvent on the precipitation phenomena and to propose a simple mathematics model for evaluating the precipitation rate of mannan (Rβ). The experiments were carried out using a semi batch system; where continuous drop wise addition of anti-solvent to the Aloe vera leaf pulp juice was kept constant at 50.4 mL/min, while the speed of stirring was maintained at 675 rpm. At every run of the experiments, the time at which the precipitation began was recorded and the experiment was terminated when no further precipitation occurred. The samples were withdrawn from the system at every 25 min after the first precipitation for mannan analysis. The results of this work showed that isopropyl alcohol acted as a more effective antisolvent to precipitate mannan from Aloe vera leaf pulp juice than methanol. The mathematics model represented the precipitation phenomena fairly well with average relative deviation only 11.73%, and finally suggested that the precipitation rate obeyed the zero order
MANNAN PRECIPITATION FROM ALOE VERA LEAF PULP JUICE USING METHANOL AND ISOPROPYL ALCOHOL AS ANTI-SOLVENT: EXPERIMENTAL AND EMPIRICAL MODELLING APPROACH
No full textPrecipitation of mannan from Aloe vera leaf pulp juice was investigated using anti-solvent
precipitation process under room temperature condition. The aims of this work were to study the
effects of types (methanol and isopropyl alcohol) and amount of anti-solvent on the precipitation
phenomena and to propose a simple mathematics model for evaluating the precipitation rate of
mannan (Rβ). The experiments were carried out using a semi batch system; where continuous drop
wise addition of anti-solvent to the Aloe vera leaf pulp juice was kept constant at 50.4 mL/min, while
the speed of stirring was maintained at 675 rpm. At every run of the experiments, the time at which the precipitation began was recorded and the experiment was terminated when no further precipitation occurred. The samples were withdrawn from the system at every 25 min after the first precipitation for mannan analysis. The results of this work showed that isopropyl alcohol acted as a more effective antisolvent to precipitate mannan from Aloe vera leaf pulp juice than methanol. The mathematics model represented the precipitation phenomena fairly well with average relative deviation only 11.73%, and finally suggested that the precipitation rate obeyed the zero order
Efeito da aloína e do extrato do parênquima clorofiliano da Aloe barbadensis na viabilidade de células tumorais e na formação de vasos sanguíneos
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Química.Aloe barbadensis, uma espécie originária do continente africano adaptada no Brasil, possui diversas propriedades medicinais determinadas por metabólitos encontrados nos extratos dos parênquimas de reserva e clorofiliano. Este último é rico em antraquinonas, sendo constituído majoritariamente de aloína. No presente trabalho, foram estudados os efeitos do extrato do parênquima clorofilano (EPC) e da aloína sobre a viabilidade de células tumorais da linhagem B16F10 in vitro e a formação de vasos sangüíneos de embriões de Gallus domesticus in vivo. Na análise in vitro, células incubadas a 37ºC em atmosfera contendo 5% de CO2, foram tratadas em diferentes concentrações de aloína e de EPC. Tanto a aloína (0,01 a 230 µg?mL-1) como o EPC (0,01 a 100 µg?mL-1) reduziram a viabilidade das células tumorais. Os dados experimentais foram representados através de um modelo matemático, evidenciando que o EPC mostrou-se 2,3 vezes mais citotóxico para as células tumorais do que a aloína. Ao contrário do verificado sobre a atividade antitumoral, a aloína (10 a 320 µg?mL-1) e o EPC (10 a 320 µg?mL-1) estimularam de modo dose-dependente a vasculo/angiogênese na membrana vitelínica (MV) em 154 e 177% e a angiogênese na membrana corioalantóica (MC) em até 131 e 164%, respectivamente. Verificou-se ainda que o efeito da aloína e do EPC superaram o efeito do fator angiogênico FGFb na formação de vasos primordiais na MV (135%), sendo que para a angiogênese, na MC, apenas o EPC foi mais efetivo que o FGFb (164% versus 158%). Os tratamentos não modificaram o padrão de crescimento e a morfogênese dos embriões, com base nas medidas de comprimento total e percentual de comprimento cefálico de embriões com quatro dias de desenvolvimento. Os resultados demonstram que a aloína e o EPC exerceram efeito citotóxico especificamente nas células tumorais, mas promoveram atividade pró-vasculogênica e pró-angiogênica, superior a do fator angiogênico FGFb, sem qualquer evidência de embriotoxicidade. Com base nos resultados é possível concluir que o EPC e a substância isolada, sob estudo, mostraram concomitantemente um potencial efeito antitumoral e uma atividade estimulante em processos fisiológicos como a vascularização de tecidos normais
PHARMACOGNOSTIC STUDY OF ALOE ARBORESCENS GROWN IN ITALY.
No full textA pharmacognostic study was carried out on Aloe arborescens Mill, grown in the Hanbury Botanic Garden at La Mortola (Italy). The results show that it is perfectly acclimatized and suggest that it may be considered of pharmaceutical interest
Blow me down:A new perspective on Aloe dichotoma mortality from windthrow
No full textBackgroundWindthrow, the uprooting of trees during storms associated with strong winds, is a well-established cause of mortality in temperate regions of the world, often with large ecological consequences. However, this phenomenon has received little attention within arid regions and is not well documented in southern Africa. Slow rates of post-disturbance recovery and projected increases in extreme weather events in arid areas mean that windthrow could be more common and have bigger impacts on these ecosystems in the future. This is of concern due to slow rates of post-disturbance recovery in arid systems and projected increases in extreme weather events in these areas. This study investigated the spatial pattern, magnitude and likely causes of windthrown mortality in relation to other forms of mortality in Aloe dichotoma, an iconic arid-adapted arborescent succulent and southern Africa climate change indicator species.ResultsWe found that windthrown mortality was greatest within the equatorward summer rainfall zone (SRZ) of its distribution (mean = 31%, n = 11), and was derived almost exclusively from the larger adult age class. A logistic modelling exercise indicated that windthrown mortality was strongly associated with greater amounts of warm season (summer) rainfall in the SRZ, higher wind speeds, and leptosols. A statistically significant interaction term between higher summer rainfall and wind speeds further increased the odds of being windthrown. While these results would benefit from improvements in the resolution of wind and substrate data, they do support the hypothesised mechanism for windthrow in A. dichotoma. This involves powerful storm gusts associated with either the current or subsequent rainfall event, heavy convective rainfall, and an associated increase in soil malleability. Shallow rooting depths in gravel-rich soils and an inflexible, top-heavy canopy structure make individuals especially prone to windthrown mortality during storms.ConclusionsResults highlight the importance of this previously unrecognised form of mortality in A. dichotoma, especially since it seems to disproportionately affect reproductively mature adult individuals in an infrequently recruiting species. Smaller, more geographically isolated and adult dominated populations in the summer rainfall zone are likely to be more vulnerable to localised extinction due to windthrow events.<br/
Avaliação do potencial hipolipemiante da quitosana e associações em ensaios pré-clínicos e clínicos fase II
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Farmácia.Elevados níveis plasmáticos de lipídeos tem sido associados a um aumento do risco de incidência de aterosclerose, sendo que ainda são poucas as opções terapêuticas para a prevenção e/ou tratamento desta doença. Neste sentido, o presente trabalho se propôs avaliar o efeito hipolipemiante da quitosana e associações a serem utilizadas como alternativas terapêuticas para hiperlipidemias. Para tanto, foram realizados ensaios pré-clínicos em ratos e clínicos fase II em humanos, os quais foram submetidos a diferentes tratamentos com quitosana, quitosana associada à Aloe vera e quitosana associada à Brassica olearaceae, com vistas a identificar as formulações mais efetivas em termos de potencial hipolipemiante. Os resultados obtidos nos ensaios pré-clínicos em ratos demonstram que tratamento com quitosana associada à Brassica olearaceae foi o mais efetivo, uma vez que foi capaz de provocar uma redução significativa nos níveis séricos de colesterol total, LDL-colesterol, VLDL-colesterol e triglicerídeos. Por sua vez, os resultados obtidos nos ensaios clínicos fase II em humanos demonstram que o tratamento com quitosana associada à Aloe vera foi o mais efetivo, sendo capaz de reduzir, significativamente, os níveis de colesterol total e LDL-colesterol. Os resultados obtidos sugerem que as associações quitosana/Brassica olearaceae e quitosana/Aloe vera se mostram como alternativas terapêuticas para quadros de hiperlipidemias, contribuindo, desta forma, para a prevenção e/ou tratamento de processos aterogênicos
Promotion of Community Based Cultivation of Hibiscus Sabdariffa, Moringa Oleifera, Adansonia Digitata and Aloe Vera for use as Herbal Nutritional Supplements for People living with HIV/AIDS
No full textProtecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
Effect of Aloe vera gel on TGF-β gene expression in incisional skin wound in BALB/c mice
No full textBackground and Objective: Aloe vera (Aloe barbadensis M.) as a medicinal herb is practiced in wound healing. This study was carried out to assess the effect of Aloe vera gel (mucilage) on TGF-β gene expression in incisional skin wound in BALB/c mice. Method: In this experimental study, 36 BALB/c male mice with weight range 22±2 gr were allocated equally into negative control (no wound), sham-operated (wound treated with physiological serum) and teratment (wound treated with Aloe vera gel). Two equal full-thickness skin wounds of 10±2mm were made on either side of the vertebral column in the sacral region. The animals in the teratment group were received daily, 2 gram of Aloe vera gel (without any bandage) as a thin layer for a period of 16 days. On 8th and 16th post wounding day, TGF-β gene expression in incisional wounds and Malonyldialdehyde (as end-product of lipid peroxidation) in serum samples was measured using RT-PCR and spectrophotometry methods, respectively. Results: TGF-β gene expression in incisional skin wound increased in Aloe vera gel treated group in compared to negative control and sham-operated groups (P<0.05). Malonyldialdehyde concentration was significantly reduced in Aloe vera treated group in comparision with negative control and sham-operated groups. Conclusion: Aloe vera gel can induce growth factor TGF-β gene expression and reducing the lipid peroxidation content can play an important role in incisional skin wound healing process
Evaluación in vitro de extractos de Aloe Vera sobre el crecimiento de S. aureus y S. mutans
No full textIntroducción: Los productos naturales se han usado desde la antigüedad y se ha adoptado con fines fitoterapéuticos para el tratamiento de enfermedades. Objetivo: Comparar el efecto antimicrobiano in vitro de las soluciones de Aloe Vera sobre el crecimiento de S. Aureus y S. mutans. Metodología: Se prepararon un extracto hidroalcohólico y otro extracto acuoso de las hojas de Aloe Vera por percolación durante 72horas y se realizó la evaluación in vitro sobre la inhibición en el crecimiento de S. Aureus y S. mutans. Se utilizaron digluconato de clorhexidina al 0,2% y cloruro de cetilpiridino en presentación comercial, como controles positivos. Resultados: Se encontró que tanto el extracto hidroalcohólico como el extracto acuoso de las hojas de Aloe Vera producidos por percolación durante 72h no produjeron halos de inhibición sobre el crecimiento de S. Aureus y S. mutans. Por otro lado, los controles positivos produjeron halos de inhibición entre 17mm y 42mm sobre el crecimiento de estos microorganismos. Conclusión: Extractos de las hojas de Aloe Vera producidos por percolación durante 72horas no mostraron efectos de inhibitorios sobre el crecimiento bacteriano de S. mutans y S. aureus.Introduction: The natural products has been used since ancient times and it has been adopted for phytotherapeutic purposes for the treatment of diseases. Objective: To compare the in vitro antimicrobial effect of Aloe Vera extracts on the growth of S. Aureus and S. mutans. Methodology: An hydroalcoholic extract and another aqueous extract of the Aloe Vera leaves were prepared by percolation for 72 hours and the in vitro evaluation of the inhibition in the growth of S. Aureus and S. mutans was carried out; 0.2% chlorhexidine digluconate and cetylpyridine chloride were used as positive controls. Results: It was found that both the hydroalcoholic extract and the aqueous extract of Aloe Vera leaves produced by percolation for 72h did not produce inhibition halos on the growth of S. Aureus and S. mutans. On the other hand, the positive controls produce inhibition halos between 17 mm and 42 mm on the growth of these microorganisms. Conclusion: Aloe Vera extracts produced by percolation for 72 hours did not show inhibitory effects on the bacterial growth of S. mutans and S. aureus.https://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=00001410700000-0001-7582-2760https://scienti.minciencias.gov.co/gruplac/jsp/visualiza/visualizagr.jsp?nro=00000000005649alejandro.pelaezv@campusucc.edu.cohttps://scholar.google.com/citations?user=jNJHWGsAAAAJ&hl=e
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