Background: Mosquitoes are responsible of numerous vector-borne diseases and among these diseases is malaria which takes away lives of thousands of people, especially children of under five, particularly in Africa. To...Background: Mosquitoes are responsible of numerous vector-borne diseases and among these diseases is malaria which takes away lives of thousands of people, especially children of under five, particularly in Africa. To reduce the mortality and economic burdens of this deadly disease, synthetic insecticide has been of use to control its main vector, Anopheles gambiae. Due to adverse effects caused by these conventional products on non-target organisms and the environment, plants have been of first choice as they proved their effectiveness against mosquitoes and are said to be eco-friendly and relatively safer. Therefore, the aim of this study was to screen the phytochemicals and determine the larvicidal and adult emergence exhibitory activities of Momordica charantia and Hyptis spicigera leaves extracts against Anopheles gambiae larvae. Methods: The WHO standard protocol for larvicidal activity and IGRs was followed up and concentrations from 500 - 2000 ppm for larvicidal and 500 - 1500 ppm for IGRs were set up. Results: There was the presence of alkaloids, flavonoids, tannins, phenols, steroids, terpenoids and oils in Momordica charantia against alkaloids, taponins, tannins, phenols, steroids, terpenoids and oils in Hyptis spicigera. Methanol crude extract registered the lowest LC<sub>50</sub> value of 270.6 ppm followed by ethyl acetate and hexane fractions recorded the LC<sub>50</sub> of 742.1 and 756 ppm, respectively for larvicidal activity of Momordica charantia against LC<sub>50</sub> of 760 and 867.5 ppm for hexane fraction and methanol crude extract, respectively for Hyptis spicigera. Methanol crude extract and hexane fraction of both plants as well as the ethyl acetate fraction of M. charantia registered greater emergence inhibition with IE<sub>50</sub> values of 590.2, 842.3 and 982 ppm for methanol crude extract, hexane and ethyl acetate fractions of M. charantia, respectively against 901.7 and 873.2 for methanol crude extract and hexane fraction of H. spicigera, respectively. Conclusion: The toxicity and adult emergence inhibition may be associated with constituents in both plants that interfere with the normal neuronal, respiratory and endocrine systems functions.展开更多
In this study, the influence of provenance and extraction methods on the physicochemical properties and the antioxidant potential of M. charantia seeds oil were evaluated. The oil is obtained on the one hand by cold e...In this study, the influence of provenance and extraction methods on the physicochemical properties and the antioxidant potential of M. charantia seeds oil were evaluated. The oil is obtained on the one hand by cold extraction with hexane and on the other hand by hot extraction with soxhlet. The results obtained show that the extraction yield is significantly impacted by the extraction methods and the origin of the seeds. In addition, the soxhlet extraction gives a higher oil yield (32.07 ± 0.01). Cold extraction has made it possible to obtain oils with less attenuated physicochemical characteristics. Indeed, the acid numbers are high in the oils extracted by soxhlet (5.92 ± 0.25;4.25 ± 0.62 and 13.86 ± 0.83) than in those cold extracted with very low peroxide for all the oils obtained. On the other hand, the iodine and refractive indices are high in oils obtained cold (91.58 ± 0.85;100.74 ± 0.03 and 102.08 ± 0.28) (1.53 ± 0.01;1.52 ± 0.01 and 1.52 ± 0.01) with low saponification indices. The polyphenol concentrations and the anti-free radical activity are higher with the oils obtained cold (0.086 ± 0.001;0.08 ± 0.000 and 0.09 ± 0.01 mgEAG/g of oil) and (DPPH) (55.75% ± 1.16%;55.03% ± 0.72% and 56.35% ± 0.45%). The color parameters (L*, a* and b*) of the different oils extracted also vary depending on the extraction method used. Principal Component Analysis (PCA) and correlation analysis were performed on the physicochemical properties and the antioxidant potential of the extracted oils. Therefore, the results suggest cold extraction to obtain a good quality and oxidation resistant oil.展开更多
文摘Background: Mosquitoes are responsible of numerous vector-borne diseases and among these diseases is malaria which takes away lives of thousands of people, especially children of under five, particularly in Africa. To reduce the mortality and economic burdens of this deadly disease, synthetic insecticide has been of use to control its main vector, Anopheles gambiae. Due to adverse effects caused by these conventional products on non-target organisms and the environment, plants have been of first choice as they proved their effectiveness against mosquitoes and are said to be eco-friendly and relatively safer. Therefore, the aim of this study was to screen the phytochemicals and determine the larvicidal and adult emergence exhibitory activities of Momordica charantia and Hyptis spicigera leaves extracts against Anopheles gambiae larvae. Methods: The WHO standard protocol for larvicidal activity and IGRs was followed up and concentrations from 500 - 2000 ppm for larvicidal and 500 - 1500 ppm for IGRs were set up. Results: There was the presence of alkaloids, flavonoids, tannins, phenols, steroids, terpenoids and oils in Momordica charantia against alkaloids, taponins, tannins, phenols, steroids, terpenoids and oils in Hyptis spicigera. Methanol crude extract registered the lowest LC<sub>50</sub> value of 270.6 ppm followed by ethyl acetate and hexane fractions recorded the LC<sub>50</sub> of 742.1 and 756 ppm, respectively for larvicidal activity of Momordica charantia against LC<sub>50</sub> of 760 and 867.5 ppm for hexane fraction and methanol crude extract, respectively for Hyptis spicigera. Methanol crude extract and hexane fraction of both plants as well as the ethyl acetate fraction of M. charantia registered greater emergence inhibition with IE<sub>50</sub> values of 590.2, 842.3 and 982 ppm for methanol crude extract, hexane and ethyl acetate fractions of M. charantia, respectively against 901.7 and 873.2 for methanol crude extract and hexane fraction of H. spicigera, respectively. Conclusion: The toxicity and adult emergence inhibition may be associated with constituents in both plants that interfere with the normal neuronal, respiratory and endocrine systems functions.
文摘In this study, the influence of provenance and extraction methods on the physicochemical properties and the antioxidant potential of M. charantia seeds oil were evaluated. The oil is obtained on the one hand by cold extraction with hexane and on the other hand by hot extraction with soxhlet. The results obtained show that the extraction yield is significantly impacted by the extraction methods and the origin of the seeds. In addition, the soxhlet extraction gives a higher oil yield (32.07 ± 0.01). Cold extraction has made it possible to obtain oils with less attenuated physicochemical characteristics. Indeed, the acid numbers are high in the oils extracted by soxhlet (5.92 ± 0.25;4.25 ± 0.62 and 13.86 ± 0.83) than in those cold extracted with very low peroxide for all the oils obtained. On the other hand, the iodine and refractive indices are high in oils obtained cold (91.58 ± 0.85;100.74 ± 0.03 and 102.08 ± 0.28) (1.53 ± 0.01;1.52 ± 0.01 and 1.52 ± 0.01) with low saponification indices. The polyphenol concentrations and the anti-free radical activity are higher with the oils obtained cold (0.086 ± 0.001;0.08 ± 0.000 and 0.09 ± 0.01 mgEAG/g of oil) and (DPPH) (55.75% ± 1.16%;55.03% ± 0.72% and 56.35% ± 0.45%). The color parameters (L*, a* and b*) of the different oils extracted also vary depending on the extraction method used. Principal Component Analysis (PCA) and correlation analysis were performed on the physicochemical properties and the antioxidant potential of the extracted oils. Therefore, the results suggest cold extraction to obtain a good quality and oxidation resistant oil.
