Anti-inflammatory and anti-nociceptive activities of essential oil of Waltheria indica / Actividades antiinflamatorias y nociceptivas del aceite esencial de Waltheria indica

This paper reports for the first time volatile compounds, anti-nociceptive and anti-inflammatory activities of essential oils from the leaves of Waltheria indica L. (Stericullaceae) growing in Nigeria. The essential oil was hydro-distilled and characterized by gas chromatography-flame ionization detection (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS) analyses. The anti-inflammatory activity was evaluated on carrageenan induced rat paw edema while the anti-nociceptive test was based on hot plate model. The hydro-distillation afforded 0.41% (dry weight basis) of light green oil. Forty compounds representing 99.8% were identified in the oil. The main constituents of the oil were limonene (34.7%), sabinene (21.2%) and citronellal (9.7%). The anti-nociceptive property of the essential oils statically inhibited edema development (p<0.001) at a dose of 200 and 400 mg/kg independent of time of exposure. However, the 100 mg/kg Waltheria indica essential oils (WIEO) displayed a relatively low inhibition (p<0.01-p>0.5) which declines as exposure time increases. The anti-inflammatory activities shows a steady rate and non-dose dependent activity (p<0.001) up to the 3rd h of inflammation study. Conversely, a sharp reduction at the rate of p<0.5, 0.1 and 0.01 for the 100, 200 and 400 mg/kg WIEO doses respectively. Overall, the results presented sustain and establish the anti-nociceptive and anti-inflammatory properties and justifies the need for further evaluation and development of the essential oils from this plant.

Este artículo informa por primera vez de compuestos volátiles, actividades anti-nociceptivas y antiinflamatorias de aceites esenciales de las hojas de Waltheria indica L. (Stericullaceae) que crecen en Nigeria. El aceite esencial fue hidro-destilado y se caracterizó por cromatografía de gases-detección de ionización de llama (GC-FID) y cromatografía de gases junto con análisis de espectrometría de masas (GC-MS). La actividad antiinflamatoria se evaluó en el edema de pata de rata inducido por carragenano, mientras que la prueba antinociceptiva se basó en el modelo de placa caliente. La destilación hidráulica proporcionó 0,41% (en peso seco) de aceite verde claro. Cuarenta compuestos que representan el 99.8% fueron identificados en el aceite. Los principales componentes del aceite fueron el limoneno (34,7%), el sabineno (21,2%) y el citronelal (9,7%). La propiedad anti-nociceptiva de los aceites esenciales inhibió estáticamente el desarrollo del edema (p<0.001) a una dosis de 200 y 400 mg/kg independientemente del tiempo de exposición. Sin embargo, los aceites esenciales de Waltheria indica de 100 mg/kg (WIEO) mostraron una inhibición relativamente baja (p<0.01-p>0.5) que disminuye a medida que aumenta el tiempo de exposición. Las actividades antiinflamatorias muestran una tasa constante y una actividad no dependiente de la dosis (p<0.001) hasta la tercera hora del estudio de inflamación. Por el contrario, una fuerte reducción a una tasa de p<0.5, 0.1 y 0.01 para las dosis de 100, 200 y 400 mg/kg de WIEO respectivamente. En general, los resultados presentados sostienen y establecen las propiedades anti-nociceptivas y antiinflamatorias y justifican la necesidad de una mayor evaluación y desarrollo de los aceites esenciales de esta planta.

Anti-inflammatory Activity of Hexane and Ethyl Acetate Extracts of Hura crepitans L.

Aims: The present research aimed to evaluate the anti-inflammatory action of hexane and ethyl acetate extracts of Hura crepitans L. (Euphorbiaceae) grown in Nigeria Study Design: The study involves the extraction of crude extracts from the leaf of H. crepitans and the evaluation of their anti-inflammatory potential. Place and Duration of Study: Fresh leaves of H. crepitans were collected from Festac Town, Amuwo-Odofin in Lagos, Nigeria (6.4664oN, 3.2835oE). The sheets were air-dried in the laboratory of Lagos State University where the extraction of crude and anti-inflammatory studies took place. The study lasted between March and November 2017. Methodology: The dried and pulverised leaves (0.5 kg) of H. crepitans were separately macerated in hexane and ethyl acetate for five (5) days in an airtight bottle and shook periodically (agitation) to maximise full extraction of the phyto-constituents. The extracts were decanted, filtered and concentrated on a rotary evaporator to obtained dried samples. The anti-inflammatory activity was determined on fresh egg albumins over 4 h by measurement of rat paw edema according to established procedure. Results: The result of the extraction shows that more phytochemicals are present in the ethyl acetate extract (15.0%) as compared to the hexane extract (7.2%). The anti-inflammatory activities of the ethyl acetate and hexane extracts of H. crepitans on Wistar rats using egg-albumin as phlogistic agents shows a moderate inhibition with a significant value of P< 0.05 at a dose of 200 mg/kg orally. Percentage inhibition of the anti-inflammation decreases steadily from the 1st hr to the 4th hr for the hexane extract (11.7 to 1.5% ) while there was an increment in the ethyl acetate extract from 12% to 32.5% for the 1st and the 4th hr respectively when compared with the control. Conclusion: This study has shown that the extracts of H. crepitans leaves possessed a significant anti-oedematogenic effect on paw oedema induced by egg-albumin by inhibiting the release of mediators for the entire 4 h experimental period.