Larvicidal Activity Of Methanolic Extracts Research Articles

Biopotential of microalgal extracts as a mosquito larvicide: An eco-friendly approach to control Aedes aegypti

Introduction and Aim: The use of chemical pesticides has raised concerns about their safety and toxicological effects on the environment, people, and other species. Therefore, there is a demand for natural alternatives that are eco- friendly, biodegradable, and target specific. The purpose of this study was to test the larvicidal activity of three microalgae namely, Chlorella sp., Chlorococcum sp., and Scenedesmus sp., against Aedes aegypti. Materials and Methods: The microalgal extracts were prepared with different concentrations after suitable pretreatment and extraction process. The effect of extracts was tested on Aedes aegypti larvae exposed to different concentrations after 24 and 48 hours. Results: The ethanol extract of the Scenedesmus sp. showed the highest larvicidal activity. Whereas the larvicidal activity of methanol extract of the Chlorococcum sp. was the lowest. The phytochemical screening of algal extracts revealed the presence of phytochemicals present in the microalgal extracts namely flavonoids, terpenoids, alkaloids, quinones, saponins, and cellulose Conclusion: This study demonstrated the biopotential of microalgae extracts for the control of the dengue vector, Aedes aegypti. Thus, the use of microalgae can be considered as an alternative to the conventional insecticides as it is more sustainable, non-toxic, and eco-friendly.

A IMPACT OF HYGROPHILA AURICULATA-GREEN MOSQUITOCIDAL ACTIVITY AGAINST MALARIA VECTOR, ANOPHELES STEPHENSI (DIPTERA: CULICIDAE)

Objective: Mosquitoes are insect vectors responsible for the transmission of parasitic and viral infections to millions of people worldwide, with substantial morbidity and mortality. Insecticides of botanical origin may serve as suitable alternative bio-control techniques in the future.
 Methods: The egg hatchability, growth regulatory, longevity, fecundity, and larvicidal activity of crude methanol leaf extract of Hygrophila auriculata were assayed for their toxicity tested against malarial vector mosquito, Anopheles stephensi.
 Results: The eggs, larvae, larvae/pupae, and cumulative mortality were observed hatching rates for 100 ppm, 0–18 h (18 h exposed) at 24, 48, and 72 h, respectively, and mortality was 33.4, 44.6, 17.9, and 95.9% methanolic extract treatment, with the lethal concentration 50 (LC50)/LC90 values were 35.420 28/75.600 ppm. Effect of methanolic extract was larval, pupal, and adult duration and water extracts of caused longest delayed development from 16.6 days larvae, 7.5 days for pupae and longevity of adult female greatly reduced from 25.9 days and fecundity also reduced from 68.0 at 150 ppm. The larvicidal activity of methanol extract was decreased at 48 h as for instars larvae 63.44/271.95 ppm (I), 57.55/272.48 ppm (II); 62.49/301.22 ppm (III); 67.69/330.48 ppm (IV), and 76.99/343.82 ppm (pupae), respectively.
 Conclusion: These results suggest that the methanol leaf extract has the potential to be used as an ideal eco-friendly approach for the control of mosquito vector. Therefore, this study provides on the mosquito eggs, larvae, and pupae activities of these plant methanol extract against A. stephensi.

Mosquitocidal Activity of the Pale Brittle Stem Mushroom, Psathyrella candolleana (Agaricomycetes), against Three Vector Mosquitoes.

The aim of the present study was to screen for mosquito larvicidal activity of methanol extract of a wild mushroom Psathyrella candolleana against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. Larvae and eggs were exposed to four different concentrations (62.5, 125, 250, and 500 ppm) and mortality was assessed 24 and 120 h after treatment. The LC50 and LC90 values of the extract were calculated. Methanol crude extract of P. candolleana showed good larvicidal activity against the third instar larvae of Cx. quinquefasciatus with LC50 and LC90 values of 166.713 and 259.17 ppm, respectively, after 24 h of exposure. No larvicidal activity was observed against Ae. aegypti and An. stephensi. The methanol extract of P. candolleana presented 88% ovicidal activity against Cx. quinquefasciatus at 500 ppm concentration 120 h after treatment. The active methanol extract was tested for toxicity against non-target organism and found was to have no toxicity. Histopathological studies of the treated larvae revealed serious damages to the midgut cells. The mushroom species was confirmed by 5.8S rRNA sequence and phylogenetic tree was constructed. These results suggest that the methanol extract of P. candolleana could be used in Cx. quinquefasciatus control programs as a new eco-friendly larvicide.

Perbedaan Aktivitas Larvisida Antara Ekstrak Metanol, Etil Asetat dan Kloroform Rimpang Zingiber zerumbet (L) Smith pada Aedes aegypti (Diptera: Culicidae)

Akhir-akhir ini banyak ditemukan bahwa larva nyamuk telah resisten terhadap larvisida konvensional. Oleh karena itu, perlu dikembangkan larvisida baru dari bahan alam. Salah satu bahan alam yang dapat digunakan sebagai larvisida adalah rimpang Z. zerumbet, yang pada penelitian sebelumnya berpotensi sebagai larvisida pada Artemia salina Leach dan Anopheles nunestovary. Penggunaan beberapa solven untuk melihat aktivitas larvisida terbaik pada Z. zerumbet belum pernah diteliti. Tujuan penelitian ini untuk mengkaji aktivitas larvisida ekstrak methanol, etil asetat dan kloroform pada A. aegypti. Penelitian ini merupakan penelitian eksplorasi laboratories dengan rancangan posttest-only control group. Penelitian dilakukan pada tiga macam ekstrak Z. zerumbet dengan perbedaan solven yaitu methanol, etil asetat dan kloroform. Dua puluh lima larva instar III-IV Ae.aegypti dipejankan dengan tujuh konsentrasi yang berbeda dari ketiga ekstrak rimpang Z. zerumbet. Tingkat kematian larva dihitung dan kemudian dianalisis menggunakan regresi analisa probit untuk mendapatkan nilai LC50 dan LC90. Nilai LC50 dan LC90 ketiga ekstrak methanol; etil asetat dan kloroform adalah; 153,57; 185,80; 3542,03 ppm dan; 226,59 ; 274,70 ; 5567,24 ppm. Ekstrak methanol rimpang Z. zerumbet memiliki aktivitas larvisida yang kuat terhadap larva instar III-IV Ae.aegypti dibandingkan dengan ekstrak lainnya.

PRELIMINARY PHYTOCHEMICAL ANALYSIS AND LARVICIDAL ACTIVITY OF EDIBLE FERN (Diplazium esculentum (Retz.) Sw.) EXTRACT AGAINST Culex

Mosquito is one of insects spreading the vector of serious diseases to human being through its bite such as Culex which spreads the vector of filariasis and brain inflammatory diseases. Some people have used plants as insecticides traditionally, such as fern (Diplazium esculentum (Retz.) Sw.). D. esculentum (Retz.) Sw. popularly known as edible fern which almost all Asian people, especially Indonesian consumed it as vegetable, and some people also used it for medicinal purposes. This study was performed to investigate the secondary metabolites from D. esculentum leaves and its larvicidal activity against Culex. The phytochemical screening was undertaken on the leaves and methanol extract of D. esculentum, the results showed the presence of alkaloids, steroids, phenols, and tannins on leaves, while methanol extract exhibited existence of steroids, saponins, phenols and tannins. Investigation of larvicidal activity of methanol extract was carried out against Culex larvaes for various concentrations which observed for 48 hours. Percentage of mortality was analyzed statistically using Bill Test method that showed active larvicidal activity with a LC50 value of 149.279 ppm. This study indicates that fern plant have the potential as larvicidal against Culex and need to perform the further research to develop the new natural insecticides.

PRELIMINARY PHYTOCHEMICAL ANALYSIS AND LARVICIDAL ACTIVITY OF EDIBLE FERN (Diplazium esculentum (Retz.) Sw.) EXTRACT AGAINST Culex

Mosquito is one of insects spreading the vector of serious diseases to human being through its bite such as Culex which spreads the vector of filariasis and brain inflammatory diseases. Some people have used plants as insecticides traditionally, such as fern (Diplazium esculentum (Retz.) Sw.). D. esculentum (Retz.) Sw. popularly known as edible fern which almost all Asian people, especially Indonesian consumed it as vegetable, and some people also used it for medicinal purposes. This study was performed to investigate the secondary metabolites from D. esculentum leaves and its larvicidal activity against Culex. The phytochemical screening was undertaken on the leaves and methanol extract of D. esculentum, the results showed the presence of alkaloids, steroids, phenols, and tannins on leaves, while methanol extract exhibited existence of steroids, saponins, phenols and tannins. Investigation of larvicidal activity of methanol extract was carried out against Culex larvaes for various concentrations which observed for 48 hours. Percentage of mortality was analyzed statistically using Bill Test method that showed active larvicidal activity with a LC50 value of 149.279 ppm. This study indicates that fern plant have the potential as larvicidal against Culex and need to perform the further research to develop the new natural insecticides.

Larvicidal Effect of Seeds of Myristica Fragrans (Houttuyn) on Larvae of Anopheles Gambiae

The Larvicidal Activity of Methanol extract and fractions of Myristica fragrans (Myristicaceae) was evaluated on larvae of Anopheles gambiae. The seeds were macerated in 100% redistilled n-hexane for 24 hours to extract the oil, then in 100% redistilled methanol for 72hours, filtered and concentrated to dryness. The methanol crude extract of M. fragrans seeds exhibited % mortalities range of 30.00 + 0.00 -100+0.00 and LC50 of 0.02 mg/mL. N-hexane fraction of M. fragrans seeds was equally as active fraction with % mortalities range of 25+ 1.00-100+0.00 and LC50 of 0.02mg/mL. The reference compound Nicotine had %mortality range of 15.00+ 0.00 – 100.00+0.00 with LC50 of 0.04mg/mL.

Evaluation of some medicinal plants in controlling Culex pipiens.

The study evaluated the efficacy of methanolic extracts of Ruta chalepensis (Rutaceae), Withania somnifera (Solanaceae), Cleome paradoxa (Capparaceae) and Heliotropium longiflorum (Boraginaceae) aerial parts against Culex pipiens larvae. Different concentrations (100-500 ppm) of the methanolic extracts of the plants were tested towards larval mortality and development of C. pipiens separately. Larval mortalities were counted at 2, 4 & 10 days after treatment. Egg hatchability was determined at 4 & 7 days after treatment. Successful pupation and adult emergence percentage were recorded daily till all control adults emerged. All plants extracts exhibited variable activities. The greatest effect was with R. chalepensis which showed acute (2 days) and chronic (10 days) LC50 of 132.6 & 96.56 ppm, respectively. Larval mortality up to 84.47% &85.53%, were observed with C. paradoxa and R. Chalepensis respectively. Egg hatch was significantly reduced about equal with R. chalepensis and W. somnifera extracts. Concentration levels of C. paradoxa (≥200 ppm) and H. longiflorum (>400 ppm) showed significant hindrance to the larval development and reduction to resulting pupae and adults. Drastic development retardation was shown with extract of C. paradoxa leaves (300 ppm), but only 15.3% & 5.6% of larvae reach pupal and adult stages respectively. The larvicidal activity of methanolic extracts of R. chalepensis, W somnifera, C. paradoxa, H. longiflorum proved to be effective against C. pipiens larvae without any human or animal risk.

Effect of Rootstock on Mango Fruit Susceptibility to Infestation by Anastrepha obliqua

The effect of the use of rootstock Criollo on the susceptibility of Manila mango fruit to infestation by Anastrepha obliqua (Macquart) was determined in the present investigation. Growth, quality parameters (Soluble solids content (%), citric acid content (%), firmness, monoterpene volatiles (3-carene, limonene, alpha-pinene, and beta-myrcene), main flavonoids content (milligrams/100 g fresh pulp), and larvicidal activity of methanolic extracts, as well as the degree of infestation during preharvest development of the fruits were analyzed. The results indicated that the rootstock did not have any significant effect on growth, soluble solids content, or citric acid content; although it increased firmness as well as 3-carene levels and main flavonoids content, resulting in a greater resistance to infestation by A. obliqua. The obtained results support the use of this rootstock because of the beneficial effects observed on the resistance of mango fruit to infestation by this fruit fly.

Larvicidal Activity of Australian and Mexican Plant Extracts Against Aedes aegypti and Culex pipiens pallens (Diptera: Culicidae)

Larvicidal activity of methanol extracts of 22 Australian and 12 Mexican plants against early 4th-instar larvae of Aedes aegypti and Culex pipiens pallens was examined. At 200 ppm, 100% mortality in larvae of A. aegypti and C. pipiens pallens was obtained in extracts of Kigelia pinnata and Ruta chalepensis. The extract of K. pinnata gave 76.3 and 80.3% mortalities in larvae of A. aegypti and C. pipiens pallens at 100 ppm but, at 50 ppm, 23.7 and 42.1% mortality against larvae of A. aegypti and C. pipiens pallens, respectively. The extract of R. chalepensis gave 81.2 and 87.9% mortality in larvae of A. aegypti and C. pipiens pallens at 100 ppm but 23.4 and 53.3% mortality against larvae of A. aegypti and C. pipiens pallens at 50 ppm, respectively. Larvicidal activities of K. pinnata and R. chalepensis extracts were significantly reduced when used at 25 ppm. Consequently, further studies of these plants as possible agents for mosquito control are warranted.