Cytotoxic/antiproliferative and nutraceutical activity of aqueous and ethanolic extracts of green and mature Averrhoa carambola.

Averrhoa carambola L. presents in its composition diversity of nutrients and vitamins. The present study aimed to extract water and fat-soluble compounds from this fruit at different stages of maturation (green and mature), perform the physical-chemical characterization as well as evaluate its cytotoxicity against hepatoma cells of Rattus norvegicus (HTC). The physicochemical results showed that the pH and molar acidity is influenced by the fruit maturation state. The fruit presented high percentage of moisture, while the percentage of total minerals (ash) increased according to its maturation stage. The results of the phytochemical screening showed that star fruits present phenolic compounds. The antioxidant activity showed greater potential for the ethanolic extracts of the green and mature star fruit. For HTC cells treated with ethanolic extract of green and mature star fruit the data show absence of cytotoxic effect. The tests with the aqueous extract showed cytotoxic/antiproliferative effect of green and mature star fruit extract, in 24, 48 and 72 hours. The presence of nutraceutical compounds and the cytotoxic/antiproliferative activity were more expressive in the aqueous extract, being an option of easily accessible solvent economic and not harmful to organisms.

Cytotoxicity of isolated compounds from Picrasma crenata (Vell.) Engl. in animal tumor cell (HTC).

The study aim was to evaluate the cytotoxic activity, using the MTT test [3-(4,5-Dimethilthiazol-2-yl)-2,5-diphenil tetrazolium bromide], from the crude extract of Picrasma crenata (Pau Tenente) and its isolated compounds, quassin and parain, in culture of rat liver tumor cells (HTC). The test was carried out exposing the cells for 24, 48 and 72 hours to concentrations of 5, 10, 50, 100, 200, 300, 400, 500 and 1000 µg of crude extract of Pau Tenente/mL of culture medium and 1, 5, 10, 15, 20, 40, 60, 80 and 100 µg of quassin or parain compounds/mL of culture medium. The absorbances averages results obtained showed that the crude extract did not present cytotoxicity for the HTC cells in all the concentrations and evaluated times. For quassin, the concentrations of 80 and 100 µg/mL were cytotoxic, after 72 hours of treatment. For parain, the concentrations of 1, 5, 20, 40, 60, 80 and 100 µg/mL, in 72 hours, were cytotoxic, revealing a new activity for this compound. Thus, the results demonstrate a first indication of the cytotoxic activity of compounds quassin and parain, adding an important social and economic value to them, and may have application in future research and in pharmaceutical industry.

Cytotoxicity of capsaicin and its analogs in vitro.

Capsaicin (CAP) is the main compound responsible for the spicy flavor of Capsicum plants. However, its application can be inhibited due to its pungency and toxicity. This study aimed to evaluate and compare the cytotoxic effect of CAP and its analogs N-benzylbutanamide (AN1), N-(3-methoxybenzyl) butanamide (AN2), N-(4-hydroxy-3-methoxybenzyl) butanamide (AN3), N-(4-hydroxy-3-methoxybenzyl) hexanamide (AN4) and N-(4-hydroxy-3-methoxybenzyl) tetradecanamide (AN5) on the hepatoma cells of Rattus norvegicus using the MTT test. The results showed cytotoxicity of CAP at concentrations of 100, 150, 175, and 200 µM (24 hours), AN1 at 150 and 175 µM (48 hours), AN2 at 50 µM (24 hours) and 10, 25, 50, and 75 µM (48 hours), AN4 at 175 µM (24 hours), and AN5 at 50 µM (48 hours). Removing the hydroxyl radical from the vanillyl group of capsaicin, together with reducing the acyl chain to 3 carbons, which is the case of AN2, resulted in the best biological activity. Increasing the carbon chain in the acyl group of the capsaicin molecule, which is the case of AN5, also showed evident cytotoxic effects. The present study proves that the chemical modifications of capsaicin changed its biological activity.

Antimutagenicity and antigenotoxicity of Aloe arborescens Miller and Aloe barbadensis Miller in Aspergillus nidulans and Wistar rats.

Medicinal plants such as Aloe arborescens Miller and Aloe barbadensis Miller are used by the general population to treat various diseases. Therefore, the aim of this study was to evaluate the antimutagenicity of these two species using a methG1 system in Aspergillus nidulans and the comet assay in rats. The animals were treated with the plants at concentrations of 360 and 720 mg/kg body weight (1 and 2, respectively) by gavage for 14 days, followed by the administration of etoposide on treatment day 8. Blood samples were prepared for analysis of DNA damage. For the test in A. nidulans, the biA1methG1 lineage conidia were treated for 4 h with both plant species at concentrations of 4 and 8% (w/v). Then, they were washed and plated on a selective medium for frequency analysis of survival and mutation. The results of the comet assay showed that both plants were antigenotoxic compared to etoposide, which was not a typical response of methG1 systems, where only the highest concentration of plant extracts usually exhibit beneficial effects. This study demonstrates the potential antigenotoxicity and antimutagenicity of the Aloe plants tested and, therefore, supports their use as a form of preventive therapy and for health maintenance by the population.

Efeito da Aloe arborescens Miller e da Aloe barbadensis Miller sobre o desenvolvimento vegetativo em Aspergillus nidulans / Effects of the Aloe arborescens Millerand Aloe barbadensis Milleron over vegetative growth in the Aspergillus nidulans

RESUMOA pesquisa de produtos naturais benéficos à saúde humana vem crescendo nos últimos 20 anos. Considerando que as plantas de Aloe são amplamente utilizadas pela população humana, em geral de maneira terapêutica, o objetivo deste estudo foi avaliar os efeitos de Aloearborescens Miller e Aloe barbadensis Miller, sobre o desenvolvimento vegetativo de linhagens normais e mutantes de Aspergillus nidulans. Conídios da linhagem biA1methG1, MSE e CLB3 de A. nidulans, foram inoculados em meio completo sem (Controle) e com extratos das duas espécies incubados por 2, 4, 6 e 8 horas a 37ºC, no escuro. Foi analisado em microscópio óptico, 200 conídios de cada tratamento. Para o desenvolvimento das colônias, as linhagens foram inoculadas no centro das placas juntamente com o meio de cultura sólido e sobre a membrana de diálise, visando a medição do diâmetro e do peso. A análise estatística foi baseada no teste de Tukey e todos os procedimentos experimentais foram conduzidos em triplicata. Todas as linhagens apresentaram interferências positivas quando expostas às plantas de Aloe, porém, de maneira variada. Ambas as espécies aceleraram a germinação em todas as linhagens testadas e atuaram na redução significativa de conídios mortos e/ou malformados. Em relação ao desenvolvimento vegetativo, todos os dados referentes ao peso úmido e diâmetro corrigido dos tratamentos demonstraram progressos, contudo, a razão diâmetro/peso apresentou somente na linhagem MSE, ação favorável dos tratamentos naturais. As informações deste estudo sugerem benefícios de A. arborescens e A. barbadensis, justificando a importância e continuidade da investigação, para melhor elucidar os mecanismos de ação dessas plantas.

ABSTRACTThe researches about natural products that arebeneficial to human health have been growing over the past 20 years. Since Aloe plants are broadly used by the general population, frequently due to therapeutic reasons, the objective of this study was to evaluate the effects of Aloe arborescens Millerand Aloe barbadensis Miller on the vegetative growth of normal and mutant strains of Aspergillus nidulans. The conidia of thebiA1methG1, MSE and CLB3 strains of A. nidulans were inoculated in complete environment without (control) and with extracts of two species of Aloeincubated for 2, 4, 6 and 8 hours at 37˚C. 200 conidia were analyzed by optical microscopy. For the development of the colonies, the strains were inoculated in the center of the plates together with the solid environment of the cultivation and over the dialysis membrane for measuring the diameter and weighing. The statistical analysis was based on the Tukey test and all experimental procedures were performed in triplicate. All strains showed positive interference when exposed to Aloe plants, however, through different manners. Both species have accelerated the germination in all tested strains and acted in the significant reduction of dead and / or malformed conidia. Regarding the vegetative growth, all data related to wet weight and corrected diameter of the treatments revealed progress, however, the ratio diameter/weightpresented improvement only in the MSE lineage, favorable action of natural treatments. The information from this study suggest that A. arborescens and A. barbadensis are beneficial, thus justifying the importance of research maintenance in order to better elucidate the action mechanisms of these plants.

Antimutagenic and radioprotective activities of beta-carotene against the biological effects of iodine-131 radiopharmaceutical in Wistar rats.

Radioactive iodine-131 (131I) is used in the treatment and diagnosis of thyroid gland injuries. However, because it emits ionizing radiation, it causes harmful effects to cells. Given that beta-carotene (BC) has antioxidant and antigenotoxic properties, this study aimed to investigate its radioprotective and antimutagenic activity in relation to 131I at the dose that is used to treat hyperthyroidism using a test system of bone marrow cells from Wistar rats (Rattus norvegicus). The doses were 0.2 mL of 8 mg BC/mL corn oil and 25 µCi 131I per 100 g body weight, and they were given via gavage in acute and subchronic treatments. Treatment groups included simultaneous, pre-treatment, post-treatment, and continuous treatment types. In all antimutagenic acute treatments, BC had a significant antimutagenic/radioprotective activity in relation to 131I. In subchronic antimutagenic treatments, BC reduced the damage that was caused by the radioisotope; however, this reduction was not statistically significant because of the relatively low percentage of chromosomal abnormalities that were observed with only 131I compared to the acute treatment. These results demonstrate the radioprotective and antimutagenic activity of BC, indicating its use by the population, which inevitably is exposed to mutagenic agents, as a means of health protection.