The meliacins (limonoids). Biosynthesis of nimbolide in the leaves of Azadirachta indica

Ekong, D. E. U.; Ibiyemi, Samuel A.; Olagbemi, E. O.

doi:10.1039/c29710001117

Cited by 29 publications

(19 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Apparently, the tirucallane system does not get directly transformed to limonoids. In fact, the biosynthetic studies of the limonoid nimbolide (Ekong et al, 1971;Ekong and Ibiyemi, 1985) had shown that euphol and apo-euphol rather than the tirucallol systems are the preferred intermediates in the biosynthesis of the limonoid. This hypothesis could explain the isolation of the tirucallane and not the euphane system which is biogenetically transformed to limonoids while the tirucallane system does not usually get transformed to limonoids.…”

Section: Resultsmentioning

confidence: 97%

Tirucallane triterpenes from the leaf extract of Entandrophragma angolense

et al. 2005

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 97%

Tirucallane triterpenes from the leaf extract of Entandrophragma angolense

et al. 2005

View full text Add to dashboard Cite

“…The antimalarial activity of the plant has been attributed to the presence of β-sitosterol (Basak and Chakraborty, 1968); nimbolide (Ekong et al, 1971); gedunin and other limonoids (Khalid et al, 1989).…”

Section: Discussionmentioning

confidence: 99%

“…A number of workers have shown that this plant is useful in the management of malaria therapy (Ekanem, 1978). Several active components have been isolated from the extracts of this plant so it implies that not only one of these compounds is responsible for the antimalarial activity of the plant (Basak and Chakraborty, 1968;Ekong et al, 1971;Khalid et al, 1989).…”

Section: Introductionmentioning

confidence: 99%

Evaluation of the antimalarial properties and standardization of tablets of Azadirachta indica (Meliaceae) in mice

Isah

Ibrahim

Iwalewa

2003

Phytotherapy Research

View full text Add to dashboard Cite

The antimalarial activities of the tablet suspension of the bark and leaf of Azadirachta indica were evaluated on Plasmodium yoelli nigeriensis infected mice. The tablet suspensions exhibited high prophylactic, mode-rate suppressive and a very minimal curative schizonticidal effect. No animal was cured of the infection in the curative test and there was not much increase in the survival time of the animals compared with the control. The tablet suspensions from the leaf and bark at a concentration of 800 mg/kg and chloroquine at a concentration of 62.5 mg/kg body weight produced average percentage (%) parasitaemia of 79.6%, 68.2% and 99.5% for leaf, bark and chloroquine, respectively, in chemosuppression. Also in the prophylactic treatment, the tablet suspensions at 800 mg/kg and pyrimethamine at a concentration of 0.35 mg/kg gave an average parasitaemia reduction of 75.3%, 65.6% and 98.3% for the leaf, bark and pyrimethamine, respectively. There was a clear indication that both tablet suspensions from the leaf and bark possess antimalarial activity and a suspension from the former is relatively more effective than the bark. Extrapolation of the results from the antimalarial activity of the tablet suspension of the crude plant parts showed that an adult human would need to ingest a minimum of 48 g of the powdered plant material per day, an amount that is impracticable. A survival index value of 0.33 was obtained with the 800 mg/kg dose level, indicating that the tablet suspension has some moderate beneficial effect.

show abstract

“…Im Petrolather-Extrakt der Wurzel indischer Herkunft wurden die unverseifbaren Anteile mit Girard-T-Reagenz [18] in eine Keton-und eine Restfraktion aufgetrennt. Die Keton-Fraktion zeigte im D C drei Flecken, von denen sich zwei als 24-Methylencycloartanon und Cycloeucalenon erwiesen, die auch im Stammholz [15,17] vorkornmen. Fur den dritten Fleck ergab sich aus den spektroskopischen Daten der Hinweis, dai3 es sich um das schwer trennbare Gemisch aus Stigmast-4-en-3-on und Campest-4-en-3-on handelt, das auch aus der Stammrinde [12]…”

Section: Ergebnisseunclassified