In-vivo antimalarial activity of Cassia occidentalis, Morinda morindoides and Phyllanthus niruri.

The ethanolic, dichloromethane and lyophilized aqueous extracts of Cassia occidentalis root bark, Morinda morindoides leaves and whole plants of Phyllanthus niruri were evaluated for their antimalarial actvity in vivo, in 4-day, suppressive assays against Plasmodium berghei ANKA in mice. No toxic effect or mortality was observed in mice treated, orally, with any of the extracts as a single dose, of 500 mg/kg body weight, or as the same dose given twice weekly for 4 weeks (to give a total dose of 4 g/kg). No significant lesions were observed, by eye or during histopathological examinations, in the hearts, lungs, spleens, kidneys, livers, large intestines or brains of any mouse. At doses of 200 mg/kg, all the ethanolic and dichloromethane extracts produced significant chemosuppressions of parasitaemia (of > 60% for C. occidentalis root bark and Ph. niruri whole plant, and of 30% for M. morindoides leaves) when administered orally. The most active ethanolic extract, that of Ph. niruri, reduced parasitaemia by 73%. The dichloromethane extracts of M. morindoides and Ph. niruri produced similar reductions (74% and 72% chemosuppression, respectively), whereas that of C. occidentalis was slightly less active (60% chemosuppression). Each lyophilized aqueous extract was less active than the corresponding ethanolic extract.

Anti-diarrhoeal and gastro-intestinal potentials of the aqueous extract of Phyllanthus amarus (Euphorbiaceae).

The anti-diarrhoeal and gastro-intestinal protective potentials of aqueous extract of leaves of Phyllanthus amarus were investigated in mice. Graded doses of the aqueous extract (100-800 mg/kg) administered orally produced a dose-related inhibition of gut meal travel distance in normal mice. The highest intestinal transit inhibition of 31.65% was obtained with 400 mg/kg. In castor oil induced diarrhoea in mice, P. amarus extract (400 mg/kg) delayed the onset of diarrhoea, reduced frequency of defecation and reduced gut meal travel distance significantly resulting in intestinal transit inhibition of 79.94% compared to 86.92% produced by morphine (100 mg/kg). In addition, the activities of some intestinal mucosa enzymes (maltase, sucrase, lactase and alkaline phosphatase) in mice pretreated with extract before castor oil were not as severely depressed as those in the control (castor oil treated mice). Phytochemical screening revealed the presence of many secondary metabolites. The results are discussed with a view to establishing the basis of the use of this plant in traditional medicine for treatment of diarrhoea and other gastrointestinal disorders.

In vitro and in vivo evaluation of betulinic acid as an antimalarial.

The lupane-type triterpene betulinic acid was isolated from an ethanol extract of the root bark of the Tanzanian tree Uapaca nitida Müll-Arg. (Euphorbiaceae). The in vitro antiplasmodial IC50 values of betulinic acid against chloroquine resistant (K1) and sensitive (T9-96) Plasmodium falciparum were found to be 19.6 micrograms/mL and 25.9 micrograms/mL, respectively. The in vitro activities of several related triterpenes were also evaluated. Betulin was found to be inactive at 500 micrograms/mL for both K1 and T9-96. Ursolic acid exhibited IC50 values of 36.5 micrograms/mL and 28 micrograms/mL, and oleanolic acid exhibited IC50 values of 88.8 micrograms/mL and 70.6 micrograms/mL against K1 and T9-96, respectively. When betulinic acid was tested for in vivo activity in a murine malaria model (P. berghei) the top dosage employed of 250 mg/kg/day was ineffective at reducing parasitaemia and exhibited some toxicity. Betulinic acid has not previously been evaluated for in vivo activity. This is believed to be the first compound to be isolated from U. nitida.

Antimicrobial screening of Bridelia, micrantha, Alchormea cordifolia and Boerhavia diffusa.

This report is on the antimicrobial potential of Bridelia micrantha, Alchornea cordifolia and Boerhavia diffusa sourced from traditional healers through an ethnobotanical survey of antiinfective plants in Egbado South in Ogun State, Nigeria. Extracts of B. micrantha and A. cordifolia exhibited significant inhibitory activity against the pathogenic organisms. In some cases, the antibacterial activity was comparable to those of ampicillin and gentamycin. However, only the leaf of A. cordifolia showed reasonable antifungal activity when compared with Trosyd. The study shows that there is justification for the use of these medicinal plants in traditional medicine.

A trial of Phyllanthus amarus in acute viral hepatitis.

The study was done to know whether the powders of Phyllanthus amarus plants favourably influence the duration of disease in patients with acute viraus B hepatitis when compared to placebo. The powders of the plant were given in capsule form (300 mg capsules--3 capsules--3 capsules thrice daily) and an antacid powder in similar capsule was used as placebo. Persons with encephalopathy, preexisting medical conditions or serum bilirubin above 350 iu/l were excluded from the study. Fifty seven patients were randomized to receive either the placebo (28 cases) or the drug (28 cases). The two groups were comparable at the time of entry. Two cases from the placebo and one from the placebo and one from the drug group dropped out of the study. The duration of disease (time taken for bilirubin to come to below 2 mg%) was taken as the outcome measure. The duration of disease in the two groups was compared by Cox's proportional hazards analysis after adusting for the variables that influence the duration of jaundice. Only initial serum bilirubin was an independent predictor of duration of jaundice. The an analysis showed that Phyllanthus amarus powders did not significantly reduce the duration of jaundice in persons with virus B hepatitis.

Uso da poliuretana derivada do óleo de mamona para preencher defeitos ósseos diafisários segmentares do rádio: estudo experimental em coelhos / Use of polyurethane derived from castor oil to fill segmental diaphyseal bone defects in radii: an experimental study on rabbits

A biocompatibilidade e outras propriedades, como osteoinduçäo e osteoconduçäo, da poliuretana derivada da combinaçäo do óleo de mamona purificado com o pré-polímero difenilmetandiisocianato foram testadas num modelo de defeito diafisário em rádios de coelhos. Um segmento de 2cm de comprimento da diáfise radial era ressecado de ambos os rádios de cada animal e substituído por um cilindro confeccionado com a poliuretana adicionada de carbonato de cálcio para aquisiçäo de porosidade e radiodensidade. Foram utilizados 34 animais, distribuídos em grupos de acordo com o período de observaçäo pós-operatória (2, 4, 8 e 16 semanas) e submetidos a avaliaçöes radiológicas, macroscópica e histológica. Os resultados mostraram que a poliuretana era primeiro envolvida por espessa camada de tecido fibroso e, depois, por lâmina de osso de organizaçäo e maturaçäo progressivas. Näo foram observadas reaçöes de corpo estranho, nem reabsorçäo e crescimento de tecido ósseo dentro da poliuretana. Os resultados indicaram que a poliuretana derivada do óleo de mamona é material biocompatível e apresenta propriedades de osteoconduçäo e, possivelmente, de osteoinduçÒo, de grande interesse para aplicaçäo em cirurgia ortopédica.