Brown Algae Padina sanctae-crucis Børgesen: A Potential Nutraceutical.

Padina sanctae-crucis Børgesen is distributed worldwide in tropical and subtropical seas; belongs to the Dictyotaceae family, and has proven to be an exceptional source of biologically active compounds. Four compounds were isolated and identified, namely: dolastane diterpene new for the genus Padina; phaeophytin and hidroxy-phaeophytin new for the family Dictyotaceae, and; mannitol first described in this species. Saturated fatty acids as compared to the percentages of unsaturated fatty acids were shown to be present in greater abundance. Palmitic and linolenic acid were the main saturated and unsaturated acids, respectively. Cytotoxic and antioxidant activities were evaluated using human erythrocytes. In vivo evaluations of acute toxicity and genotoxicity were performed in mice. Methanolic extract of P.sanctae-crucis presented antioxidant activity and did not induce cytotoxicity, genotoxicity or acute toxicity. Since Padina sanctae-crucis is already used as food, has essential fatty acids for the nutrition of mammals, does not present toxicity and has antioxidant activity, it can be considered as a potential nutraceutical.

Toxicity and antitumor efficacy of Croton polyandrus oil against Ehrlich ascites carcinoma cells

ABSTRACT The essential oil from Croton polyandrus Spreng., Euphorbiaceae, leaves was tested for the toxicity and antitumor activity. The concentration producing 50% hemolysis was 141 µg/ml on mice erythrocytes. In the acute toxicological study, the estimated LD50 was 447.18 mg/kg. The essential oil did not induce increase in number of micronucleated erythrocytes, suggesting low genotoxicity. Essential oil (100 or 150 mg/kg) showed significant antitumor activity in Ehrlich ascitic carcinoma model. We observed that essential oil induces cell-cycle arrest at the G0/G1 phase, and increases the sub-G1 peak, which represents a marker of cell death by apoptosis. Survival also increased for the treated animals. The toxicological analyses revealed reduction in body weight, increased aspartate aminotransferase and alanine aminotransferase activity, hematological changes, and a thymus index reduction. These data suggest gastrointestinal and liver toxicity, anemia, leukopenia/lymphocytopenia, and immunosuppressive effects. Histopathological analysis revealed the weak hepatotoxicity of essential oil. In summary, essential oil of C. polyandrus displays in vivo antitumor activity and moderate toxicity.

Anti-inflammatory activity and acute toxicity studies of hydroalcoholic extract of Herissantia tiubae

ABSTRACT Hydroalcoholic extract of aerial parts of Herissantia tiubae (K. Schum.) Brizicky, Malvaceae, was evaluated in experimental models of inflammation and toxicity. For toxicity assays, male and female Swiss mice were orally treated with hydroalcoholic extract of H. tiubae (2000 mg/kg) and analyzed by consumption of water and food, body weight, mortality and rates of major organ weights, as well as biochemical and hematological indexes. For anti-inflammatory effect, phlogistic agents such as carrageenan or acetic acid were used to evaluate paw edema, cell migration and cytokine production. It was also investigated the hydroalcoholic extract of H. tiubae in RAW 264.7 macrophage lineage by nitric oxide and cytokine productions. Swiss mice treated with hydroalcoholic extract of H. tiubae showed low toxicity and (50 or 100 mg/kg) was able to reduce significantly (p < 0.01, p < 0.001) polymorphonuclear cell migration, TNF-α and IL-1β production in the carrageenan-induced peritonitis. However the hydroalcoholic extract of H. tiubae (50, 100 or 200 mg/kg) did not reduce carrageenan-induced paw edema. Additionally, hydroalcoholic extract of H. tiubae did not present cytotoxicity at concentrations of 6.25, 12.5, 25 or 50 µg/ml but induced significantly decrease of NO, TNF-α and IL-6 production in macrophage lineage. This study suggests that hydroalcoholic extract of H. tiubae has anti-inflammatory activity by inhibiting cell migration mainly by decreasing the inflammatory cytokine levels at the inflamed site independently of the anti-edematogenic effect.

Chemical composition, antitumor activity, and toxicity of essential oil from the leaves of Lippia microphylla.

The chemical composition, antitumor activity and toxicity of the essential oil from Lippia microphylla leaves (OEL) were investigated. The major constituents were thymol (46.5%), carvacrol (31.7%), p-cymene (9%), and γ-terpinene (2.9%). To evaluate the toxicity of OEL in non-tumor cells, the hemolytic assay with Swiss mice erythrocytes was performed. The concentration producing 50% hemolysis (HC50) was 300 µg/mL. Sarcoma 180 tumor growth was inhibited in vivo 38% at 50 mg/kg, and 60% at 100 mg/kg, whereas 5-FU at 50 mg/kg caused 86% inhibition. OEL displays moderate gastrointestinal and hematological toxicity along with causing some alteration in liver function and morphology. However, the changes were considered reversible and negligible in comparison to the effects of several anticancer drugs. In summary, OEL displays in vivo antitumor activity and a moderate toxicity, which suggests further pharmacological study.

Preliminary study of the molluscicidal and larvicidal properties of some essential oils and phytochemicals from medicinal plants / Estudo preliminar das propriedades moluscicidas e larvicidas de alguns óleos essenciais e fitoconstituintes de plantas medicinais

This study aimed to evaluate the molluscicidal and larvicidal activity of some essential oils and phytochemicals from medicinal plants. Molluscicide and larvicidal activity were determined by, respectively, the lethality bioassays using Artemia salina Leach. Artemiidae and Aedes aegypti L. Culicidae larvae. Essential oils from Eugenia uniflora L. Myrtaceae, Laurus nobilis L. Lauraceae, Origanum vulgare L. Lamiaceae and the phytochemicals α-pinene and eugenol presented citotoxicity toward Artemia salina with CL50 values between 9.59 and 253.43 μL/mL. Essential oils from E. uniflora, M. piperita, O. vulgare and R. officinalis showed embryotoxicity on Aedes aegypti larvae with a viability inhibition between 40 and 100 percent. These results show the bioactivity of the assayed essential oils and phytochemicals and, partially, justify their insertion in further evaluation in order to establish a safe exploitation of their biological potentiality.

Este estudo teve como objetivo avaliar a atividade moluscicida e larvicida de alguns óleos essenciais e fitoconstituintes de plantas medicinais. A atividade moluscicida e larvicida foi determinada empregando-se, respectivamente, o teste de letalidade contra náupilos de Artemia salina Leach. Artemiidae e contra larvas de Aedes aegypti L. Culicidae. Os óleos essenciais de Eugenia uniflora L. Myrtaceae, Laurus nobilis L. Lauraceae, Origanum vulgare L. Lamiaceae e os fitoconstituintes α-pineno e eugenol mostraram bioatividade citotóxica frente A. salina com valores de CL50 entre 9,59 e 253,43 μL/mL. Os óleos essenciais de E. uniflora, M. piperita, O. vulgare e R. officinalis apresentaram atividade de embriotoxicidade sobre as larvas de A. aegypti mostrando uma variação de inibição de viabilidade entre 40 e 100 por cento. Estes resultados demonstram o potencial de bioatividade desses óleos essenciais e fitoconstituintes e justificam, parcialmente, o desenvolvimento de estudos com esses produtos para uso popular.

Constituintes químicos, avaliação das atividades citotóxica e antioxidante de Mimosa paraibana Barneby (Mimosaceae) / Chemical constituents, evaluation of the cytotoxic and antioxidant activities of Mimosa paraibana Barneby (Mimosaceae)

Mimosa paraibana Barneby foi submetida a um estudo fitoquímico para o isolamento de seus constituintes químicos, através de métodos cromatográficos usuais, e posterior identificação estrutural, utilizando-se métodos espectroscópicos de RMN ¹H e 13C uni e bidimensionais, além de comparações com modelos da literatura. Deste estudo pioneiro, foram isolados e identificados cinco constituintes da fase clorofórmica: uma mistura dos esteróides, β-sitosterol e estigmasterol, a 15¹-hidroxi-feofitina A, a 5,7-dihidroxiflavanona, o 3,4,5-trihidroxibenzoato de etila e o ácido p-cumárico. A atividade antioxidante das fases hexânica, clorofórmica e acetato de etila foi avaliada utilizando o radical estável DPPH (1,1-difenil-2-picril-hidrazil) e os resultados comparados com o padrão ácido ascórbico. A avaliação da citotoxicidade das fases foi realizada empregando-se o ensaio de letalidade contra Artemia salina. Dos extratos avaliados, somente o hexânico mostrou baixa toxicidade.

The phytochemical study of Mimosa paraibana Barneby led to the isolation of its chemical constituents, through the usual chromatographic methods, and further structural identification, using ¹H and 13C NMR spectroscopic methods based on one and two-dimensional techniques, in addition to comparison with literature data. From this pioneering investigation with M. paraibana, five constituents were isolated and identified from the chloroform extract: a mixture of β-sitosterol and stigmasterol, 15¹-hydroxy-phaeophytin A, 5,7-dihydroxyflavanone, ethyl 3,4,5-trihydroxybenzoate and p-coumaric acid. The antioxidant activity of the hexane, chloroform and ethyl acetate extracts of M. paraibana were measured using the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and the results compared with standard ascorbic acid. The toxicity activity of the extracts were performed using the bioassay of Artemia salina.

The controvertible role of kava (Piper methysticum G. Foster) an anxiolytic herb, on toxic hepatitis

Kava is an anxiolytic herbal medicine used in the treatment of sleep and anxiety disorders. Some cases of kava-induced hepatotoxicity have been reported in the literature leading to its banishment in most countries worldwide. Clinically, the spectrum ranged from transient elevations of liver enzyme levels to fulminant liver failure and death. Liver transplantation was performed in a few cases. This paper provides a review of the currently available literature on kava-related toxic hepatitis which may result from its use, discusses the possible mechanisms for the potentially severe hepatotoxicity and describes some features which must be considered when adverse liver effects seem to be associated to kava administration. In conclusion, the incidence of kava toxicity on the liver remains to be investigated; however, some concerns before or during kava use are important, due to the possibility of severe liver dysfunction.

Kava é um fitoterápico ansiolítico usado no tratamento da insônia e da ansiedade. Alguns casos de hepatotoxicidade induzida pela kava foram relatados na literatura, levando à proibição do seu uso em muitos países. Clinicamente, o espectro dessas alterações variou de elevações transitórias das enzimas hepáticas, até à falência hepática fulminante e morte. Em alguns casos, realizou-se transplante hepático. Este artigo revisa a literatura atual sobre a hepatite tóxica provavelmente relacionada à kava, discute os possíveis mecanismos responsáveis pela hepatotoxicidade potencialmente grave e descreve alguns aspectos que devem ser considerados quando eventos adversos hepáticos pareçam ser relacionados à administração dessa substância. Conclui-se que a possível toxicidade hepática pela kava ainda deve ser investigada e que algumas medidas antes e durante o seu uso são importantes, dada a possibilidade de disfunção hepática grave.