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1.
Several diseases are associated to the mosquito–human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present investigation was undertaken to study the ovicidal, larvicidal and adulticidal activities of crude hexane, ethyl acetate, benzene, chloroform and methanol extracts of root of Asparagus racemosus were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera: Culicidae). The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. The methanol extract of Asparagus racemosus against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi exerted 100 % mortality (zero hatchability) at 375, 300 and 225 ppm, respectively. Control eggs showed 99–100 % hatchability. The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of root of Asparagus racemosus against the larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with the LC50 and LC90 values were 115.13, 97.71 and 90.97 ppm and 210.96, 179.92, and 168.82 ppm, respectively. The adult mortality was observed after 24 h recovery period. The plant crude extracts showed dose-dependent mortality. At higher concentrations, the adult showed restless movement for some times with abnormal wagging and then died. Among the extracts tested, the highest adulticidal activity was observed in methanol extract against Anopheles stephensi followed by Aedes aegypti and Culex quinquefasciatus with the LD50 and LD90 values were 120.44, 135.60, and 157.71 ppm and 214.65, 248.35, and 290.95 ppm, respectively. No mortality was recorded in the control. The finding of the present investigation revealed that the root extract of Asparagus racemosus possess remarkable ovicidal, larvicidal and adulticidal activity against medically important vector mosquitoes and this is the low cost and ideal eco-friendly approach for the control of mosquitoes. This is the first report on the mosquito ovicidal, larvicidal and adulticidal activities of the reported Asparagus racemosus root. 相似文献
2.
Mosquitoes are the major vector for the transmission of malaria, dengue fever, yellow fever, filariasis, schistosomiasis, and Japanese encephalitis. Mosquito control is facing a threat because of the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal, ovicidal, and adulticidal potential of the crude hexane, benzene, chloroform, ethyl acetate, and methanol solvent extracts from the medicinal plant Erythrina indica against the medically important mosquito vectors, Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of leaf of E. indica against the larvae of A. stephensi, A. aegypti, and C. quinquefasciatus with the LC50 and LC90 values of 69.43, 75.13, and 91.41 ppm and 125.49, 134.31, and 167.14 ppm, respectively. The mean percent hatchability of the eggs was observed after 48 h post treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. The methanol extract of E. indica against A. stephensi, A. aegypti, and C. quinquefasciatus exerted 100 % mortality (zero hatchability) at 150, 200, and 250 ppm, respectively. Control eggs showed above 99.3–100 % hatchability. The adult mortality was observed after 24 h recovery period. The plant crude extracts showed dose-dependent mortality. At higher concentrations, the adult showed restless movement for some times with abnormal wagging and then died. Among the extracts tested, the highest adulticidal activity was observed in methanol extract against A. stephensi followed by A. aegypti and C. quinquefasciatus with the LD50 and LD90 values of 88.76, 94.09, and 119.64 ppm and 160.83, 169.01, and 219.77 ppm, respectively. No mortality was recorded in the control. Our data suggest that the crude hexane, benzene, chloroform, ethyl acetate, and methanol solvent extracts of E. indica have the potential to be used as an eco-friendly approach for the control of the A. stephensi, A. aegypti, and C. quinquefasciatus. 相似文献
3.
Govindarajan M Mathivanan T Elumalai K Krishnappa K Anandan A 《Parasitology research》2011,109(2):353-367
Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries
with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. In mosquito control
programs, botanical origin may have the potential to be used successfully as eggs, larvae, and adult. The larvicidal, ovicidal,
and repellent activities of crude benzene and ethyl acetate extracts of leaf of Ervatamia coronaria and Caesalpinia pulcherrima were assayed for their toxicity against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae). The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects;
however, the highest larval mortality was found in benzene extract of E. coronaria against the larvae of Anopheles Stephensi, Aedes aegypti, and Culex quinquefasciatus with the LC50 and LC90 values were 79.08, 89.59, and 96.15 ppm and 150.47, 166.04, and 174.10 ppm, respectively. Mean percent hatchability of the
ovicidal activity was observed 48 h posttreatment. The percent hatchability was inversely proportional to the concentration
of extract and directly proportional to the eggs. The leaf extract of E. coronaria was found to be most effective than Caesalpinia pulcherrima against eggs/egg rafts of three vector mosquitoes. For E. coronaria, the benzene extract exerted 300, 250, and 200 ppm against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus, respectively. The results of the repellent activity of benzene and ethyl acetate extract of E. coronaria and Caesalpinia pulcherrima plants at three different concentrations of 1.0, 2.5, and 5.0 mg/cm2 were applied on skin of fore arm in man and exposed against adult female mosquitoes. In this observation, these two plant
crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent
activity is dependent on the strength of the plant extracts. These results suggest that the leaf solvent plant extracts have
the potential to be used as an ideal ecofriendly approach for the control of mosquitoes. This is the first report on the mosquito
larvicidal, ovicidal, and repellent activities of the reported E. coronaria and Caesalpinia pulcherrima plants. 相似文献
4.
The purpose of the present study was to assess the effect of crude extracts of marine actinobacteria on larvicidal, repellent,
and ovicidal activities against Culex tritaeniorhynchus and Culex gelidus (Diptera: Culicidae). The early fourth instar larvae of C. tritaeniorhynchus and C. gelidus, reared in the laboratory, were used for larvicidal, ovicidal, and repellent assay with crude extracts of actinobacteria.
Saccharomonospora spp. (LK-1), Streptomyces roseiscleroticus (LK-2), and Streptomyces gedanensis (LK-3) were identified as potential biocide producers. Based on the antimicrobial activity, three strains were chosen for
larvicidal activity. The marine actinobacterial extracts showed moderate to high larvicidal effects after 24 h of exposure
at 1,000 ppm and the highest larval mortality was found in extract of LK-3 (LC50 = 108.08 ppm and LC90 = 609.15 ppm) against the larvae of C. gelidus and (LC50 = 146.24 ppm and LC90 = 762.69 ppm) against the larvae of C. tritaeniorhynchus. Complete protections for 240 min were found in crude extract of LK-2 and LK-3 at 1,000 ppm, against mosquito bites of C. tritaeniorhynchus and C. gelidus, respectively. After 24-h treatment, mean percent hatchability of the ovicidal activity was observed. The percent hatchability
was inversely proportional to the concentration of extract and directly proportional to the eggs. Crude extracts of LK-1 and
LK-3 showed no hatchability at 1,000 ppm against C. tritaeniorhynchus and C. gelidus, respectively. This is an ideal ecofriendly approach for the control of Japanese encephalitis vectors, C. tritaeniorhynchus and C. gelidus. 相似文献
5.
Emergence of resistance among mosquitoes is a recent problem. Safe and eco-friendly agents from biological origins are the
need of the hour. Nereistoxin, a naturally occurring substance, was first isolated from the marine annelid Lumbriconereis heteropoda and stored in the freezer. In the present study, the toxicity of nereistoxin was evaluated against vector mosquitoes. The
larvicidal, ovicidal and adulticidal activities of nereistoxin were assayed for their toxicity against three important vector
mosquitoes, viz., Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae). The nereistoxin was inversely proportional to the concentration and directly proportional to the mosquitoes.
The larvicidal activity after 24 h LC50 value was observed at 0.467, 0.535 and 0.601 ppm for A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The ovicidal activity after 120 h zero percentage of egg hatchability was observed at a concentration of 0.8 ppm
for A. stephensi and 1.0 ppm for A. aegypti and C. quinquefasciatus. The results of the adulticidal activity after 24 h LD50 value were observed at 0.022, 0.028 and 0.034 ppm for A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The extracted nereistoxin was characterized and identified by ultraviolet, infrared, nuclear magnetic resonance,
mass spectroscopic methods and high pressure liquid chromatography. These results clearly reveal that the nereistoxin served
as a potential larvicidal, ovicidal and adulticidal activity against vector mosquitoes. 相似文献
6.
Nisha Mathew M. G. Anitha T. S. L. Bala S. M. Sivakumar R. Narmadha M. Kalyanasundaram 《Parasitology research》2009,104(5):1017-1025
Screening of natural products for mosquito larvicidal activity against three major mosquito vectors Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi resulted in the identification of three potential plant extracts viz., Saraca indica/asoca, Nyctanthes arbor-tristis, and Clitoria ternatea for mosquito larval control. In the case of S. indica/asoca, the petroleum ether extract of the leaves and the chloroform extract of the bark were effective against the larvae of C. quinquefasciatus with respective LC50 values 228.9 and 291.5 ppm. The LC50 values of chloroform extract of N. arbor-tristis leaves were 303.2, 518.2, and 420.2 ppm against A. aegypti, A. stephensi, and C. quinquefasciatus, respectively. The methanol and chloroform extracts of flowers of N. arbor-tristis showed larvicidal activity against larvae of A. stephensi with the respective LC50 values of 244.4 and 747.7 ppm. Among the methanol extracts of C. ternatea leaves, roots, flowers, and seeds, the seed extract was effective against the larvae of all the three species with LC50 values 65.2, 154.5, and 54.4 ppm, respectively, for A. stephensi, A. aegypti, and C. quinquefasciatus. Among the three plant species studied for mosquito larvicidal activity, C. ternatea was showing the most promising mosquito larvicidal activity. The phytochemical analysis of the promising methanolic extract
of the seed extract was positive for carbohydrates, saponins, terpenoids, tannins, and proteins. In conclusion, bioassay-guided
fractionation of effective extracts may result in identification of a useful molecule for the control of mosquito vectors. 相似文献
7.
Mosquito-borne diseases with an economic impact create loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates. Mosquito control is facing a threat because of the emergence of resistance to synthetic insecticides. Extracts from plants may be alternative sources of mosquito control agents because they constitute a rich source of bioactive compounds that are biodegradable into nontoxic products and potentially suitable for use to control mosquitoes. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the adulticidal, repellent, and ovicidal potential of the crude hexane, ethyl acetate, benzene, aqueous, and methanol solvent extracts from the medicinal plants Andrographis paniculata, Cassia occidentalis, and Euphorbia hirta against the medically important mosquito vector, Anopheles stephensi (Diptera: Culicidae).The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticide effects; however, the highest adult mortality was found in methanol extract of A. paniculata followed by C. occidentalis and E. hirta against the adults of A. stephensi with LC50 and LC90 values of 210.30, 225.91, and 263.91 ppm and 527.31, 586.36, and 621.91 ppm, respectively. The results of the repellent activity of hexane, ethyl acetate, benzene, aqueous, and methanol extract of A. paniculata, C. occidentalis, and E. hirta plants at three different concentrations of 1.0, 3.0, and 6.0 mg/cm2 were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, these three plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. Mean percent hatchability of the ovicidal activity was observed 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100 % with methanol extract of A. paniculata exerted at 150 ppm and aqueous, methanol extract of C. occidentalis and E. hirta were exerted at 300 ppm. These results suggest that the leaf extracts of A. paniculata, C. occidentalis, and E. hirta have the potential to be used as an ideal eco-friendly approach for the control of the A. stephensi. Further detailed research is needed to identify the active ingredient in the extracts and implement the effective mosquito management program. 相似文献
8.
The benzene extract of Citrullus vulgaris was tested against Anopheles stephensi and Aedes aegypti for the larvicidal activity and ovicidal properties. The crude benzene extract was found to be more effective against A. stephensi than A. aegypti. The LC50 values were 18.56 and 42.76 ppm respectively. The LC50 values for silica gel fractions (bioactive fractions I, II, III and IV) were 11.32, 14.12, 14.53 and 16.02 ppm respectively.
The mean per cent hatchability of the egg rafts were observed after 48 h post treatment. The crude extract of benzene exerted
100% mortality at 250 ppm against A. stephensi and at 300 ppm against A. aegypti. The silica gel fractions I and II afforded 100% mortality at 100 ppm and III and IV exerted the hatchability rate of 4.9
and 5.3% at the same concentration against A. stephensi. 相似文献
9.
The leaf extract of Acalypha alnifolia with different solvents — hexane, chloroform, ethyl acetate, acetone and methanol — were tested for larvicidal activity against
three important mosquitoes such as malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus. The medicinal plants were collected from the area around Kallar Hills near the Western Ghats, Coimbatore, India. A. alnifolia plant was washed with tap water and shade dried at room temperature. The dried leaves were powdered mechanically using commercial
electrical stainless steel blender. The powder 800 g of the leaf material was extract with 2.5 litre of various each organic
solvents such as hexane, chloroform, ethyl acetate, acetone, methanol for 8 h using Soxhlet apparatus, and filtered. The crude
plant extracts were evaporated to dryness in a rotary vacuum evaporator. The yield of extracts was hexane (8.64 g), chloroform
(10.74 g), ethyl acetate (9.14 g), acetone (10.02 g), and methanol (11.43 g). One gram of the each plant residue was dissolved
separately in 100 ml of acetone (stock solution) from which different concentrations, i.e., 50, 150, 250, 350 and 450 ppm,
was prepared. The hexane, chloroform, ethyl acetate, acetone was moderate considerable mortality; however, the highest larval
mortality was methanolic extract observed in three mosquito vectors. The larval mortality was observed after 24 h exposure.
No mortality was observed in the control. The early fourth-instar larvae of A. stephensi had values of LC50 = 197.37, 178.75, 164.34, 149.90 and 125.73 ppm and LC90 = 477.60, 459.21, 435.07, 416.20 and 395.50 ppm, respectively. The A. aegypti had values of LC50 = 202.15, 182.58, 160.35, 146.07 and 128.55 ppm and LC90 = 476.57, 460.83, 440.78, 415.38 and 381.67 ppm, respectively. The C. quinquefasciatus had values of LC50 = 198.79, 172.48, 151.06, 140.69 and 127.98 ppm and LC90 = 458.73, 430.66, 418.78, 408.83 and 386.26 ppm, respectively. The results of the leaf extract of A. alnifloia are promising as good larvicidal activity against the mosquito vector, A. stephensi, A. aegypti, C. quinquefasciatus. Therefore, this study provides first report on the larvicidal activities against three species of mosquito vectors of this
plant extracts from Southern India. 相似文献
10.
Plant extracts, especially botanical insecticides, are currently studied more and more because of the possibility of their
use in plant protection. Biological activity of five solvent plant extracts were studied using fourth instar larvae of gram
pod borer Helicoverpa armigera (Lepidoptera: Noctuidae), cotton leaf roller Sylepta derogata (Lepidoptera: Pyralidae) and malaria vector Anopheles stephensi (Diptera: Culicidae). Antifeedant and larvicidal activity of acetone, chloroform, ethyl acetate, hexane and methanol peel,
leaf and flower extracts of Citrus sinensis, Ocimum canum, Ocimum sanctum and Rhinacanthus nasutus were used in this study. During preliminary screening, the extracts were tested at 1,000 ppm concentration. The larval mortality
was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality
was found in peel chloroform extract of C. sinensis, flower methanol extract of O. canum against the larvae of H. armigera (LC50 = 65.10,51.78, LC90 = 277.39 and 218.18 ppm), peel methanol extract of C. sinensis, flower ethyl acetate extract of O. canum and leaf acetone extract of O. sanctum against the larvae of S. derogata (LC50 = 20.27,58.21,36.66, LC90 = 113.15,285.70 and 668.02 ppm), peel methanol extract of C. sinensis, leaf and flower ethyl acetate extracts of O. canum against the larvae of A. stephensi (LC50 = 95.74,101.53,28.96, LC90 = 303.20,492.43 and 168.05 ppm), respectively. These results suggest that the chloroform and methanol extract of C. sinensis, ethyl acetate flower extracts of O. canum and acetone extract of O. sanctum have the potential to be used as an ideal eco-friendly approach for the control of the agricultural pests H. armigera, S. derogata and medically important vector A. stephensi. 相似文献
11.
Methanolic leaf extract of Cassia fistula was tested for larvicidal and ovicidal activity against Culex quinquefasciatus and Anopheles stephensi. The extract was found to be more lethal to the larvae of A. stephensi than C. quinquefasciatus with LC50 values of 17.97 and 20.57 mg/l, respectively. Mean percent hatchability of the ovicidal activity was observed 120 h after
treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to
the eggs. The egg raft of C. quinquefasciatus was found to be more hatchable than A. stephensi. The results show that the leaf extract of C. fistula is promising as a larvicidal and ovicidal agent against C. quinquefasciatus and A. stephensi. 相似文献
12.
There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid
environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five
extracts tested for larvicidal activity against the fourth instar larvae, with LC50 of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC50 values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant
promising for the development of new botanical larvicide. 相似文献
13.
Malaria control in developing countries is based largely on vector eradication by the use of mosquito larvicides which is
an ideal method for controlling mosquito and the related epidemics. On account of ecohazardous nature, nontarget specificity
of chemical insecticides and evidences of developing resistance against them in the exposed species, currently, importance
of secondary plant metabolites has been acknowledged. Insecticides of plant origin are environmentally safe, degradable, and
target specific. In view of this fact, the present work highlights the larvicidal property of extracts of Amaranthus oleracea and Euphorbia hirta against the third instar larvae of Anopheles stephensi, the urban malaria vector. LC50 values for the carbon tetrachloride fraction of A. oleracea against larvae are 17,768.00 and 13,780.00 ppm after 24 and 48 h of exposure accordingly. For the methanol extract of the
same, LC50 values are 15,541.00 and 10,174.00 ppm after 24 and 48 h of exposure. In the case of petroleum ether extract, LC50 values after 24 and 48 h of exposure are 848.75 and 311.50 ppm. LC50 values for carbon tetrachloride extracts of E. hirta against the larvae are 11,063.00 and 10,922.00 ppm after 24 and 48 h of exposure, respectively. For methanol extract of the
same extract, the LC50 values are 19,280.00 and 18,476.00 ppm after 24 and 48 h of exposure. In the case of petroleum ether extract, LC50 values after a 24- and 48-h exposure period are 9,693.90 and 7,752.80 ppm. The results obtained for petroleum extracts of
A. oleracea are encouraging and there are probabilities that the active principle contained in this extract may be more effective than
its crude form and may serve as ecofriendly mosquito larvicide. 相似文献
14.
Prejwltta Maurya Preeti Sharma Lalit Mohan Lata Batabyal C. N. Srivastava 《Parasitology research》2009,105(6):1653-1659
In view of the recently increased interest in developing plant-based insecticides as an alternative to chemical insecticides,
this study was undertaken to assess the larvicidal potential of the various fruit wall extracts of Momordica charantia (cucurbitaceae) against two species of mosquito vectors, Anophels stephensi and Culex quinquefasciatus. Among the extracts tested, petroleum ether (LC50 = 27.60; 17.22 ppm and 41.36; 15.62 ppm) extract was found more effective than carbon tetrachloride (LC50 = 49.58; 16.15 ppm and 80.61; 27.64 ppm) and methanol (LC50 = 142.82; 95.98 ppm and 1,057.49; 579.93 ppm) extracts towards anopheline and culicine larvae after 24 and 48 h of exposure
respectively. Thus, all fruit wall extracts of M. charantia are toxic to both the larval species. M. charantia may, therefore, act as an effective biolarvicide against mosquitoes in the future. 相似文献
15.
In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed
attention as agents for vector control. The present study was undertaken to investigate the effect of aril and kernel extracts
of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol
and hexane. The extracts were tested against the 3rd–4th instar larvae collected from Bunder area, Mangalore, India, which
is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100,
200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of aril showed
100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of aril and ethanol extracts of kernel exhibited
higher toxicity against both A. albopictus (LC50, 141 ppm and 159 ppm; LC90, 290 ppm and 342 ppm) and A. stephensi (LC50, 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC90, 484 ppm), whereas ethanol extracts of aril showed the least toxicity against A. stephensi (LC50, 290; LC90, 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids
in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC50 value of the chloroform extracts of K. attenuata aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae. 相似文献
16.
G. Elango A. Abdul Rahuman A. Bagavan C. Kamaraj A. Abduz Zahir C. Venkatesan 《Parasitology research》2009,104(6):1381-1388
Anopheles subpictus and Culex tritaeniorhynchus have developed resistance to various synthetic insecticides, making its control increasingly difficult. Insecticides of botanical
origin may serve as suitable alternative biocontrol techniques in the future. The leaf acetone, chloroform, ethyl acetate,
hexane, and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb, Andrographis lineata Wallich ex Nees., Andrographis paniculata (Burm.f.) Wall. ex Nees., Cocculus hirsutus (L.) Diels, Eclipta prostrata L., and Tagetes erecta L. were tested against fourth-instar larvae of malaria vector, A. subpictus Grassi and Japanese encephalitis vector, C. tritaeniorhynchus Giles (Diptera: Culicidae). All plant extracts showed moderate larvicidal effects after 24 h of exposure at 1,000 ppm; however,
the highest larval mortality was found in leaf ethyl acetate of A. marmelos, E. prostrata, hexane, methanol of A. paniculata and C. hirsutus against the larvae of A. subpictus (LC50 = 167.00, 78.28, 67.24, 142.83 ppm; LC90 = 588.31, 360.75, 371.91, and 830.01 ppm) and against the larvae of C. tritaeniorhynchus (LC50 = 99.03, 119.89, 88.50, 105.19 ppm; LC90 = 479.23, 564.85, 416.39, and 507.86 ppm), respectively. These results suggest that the leaf hexane extract of A. paniculata and ethyl acetate extract of E. prostrata have the potential to be used as an ideal eco-friendly approach for the control of the A. subpictus and C. tritaeniorhynchus. Therefore, this study provides first report on the mosquito larvicidal activity of plant extracts against vectors from Southern
India. 相似文献
17.
G. Elango A. Bagavan C. Kamaraj A. Abduz Zahir A. Abdul Rahuman 《Parasitology research》2009,105(6):1567-1576
Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The leaf acetone,
ethyl acetate, and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb, Andrographis lineata Wallich ex Nees, and Cocculus hirsutus (L.) Diels were tested for oviposition-deterrent, ovicidal, and repellent activities against Anopheles subpictus Grassi (Diptera: Culicidae). The percentage of effective oviposition repellency of 92.60 , 93.04, 95.20, 88.26, 92.80, 94.01,
95.77, 96.93, and 92.54 at 500 ppm and the lowest repellency of 47.14, 58.00, 56.52, 64.93, 71.09, 66.42, 50.62, 57.62, and
65.73 at 31.25 ppm in acetone, ethyl acetate, and methanol extracts of Aegle marmelos, Andrographis lineata, and Cocculus hirsutus, respectively. The oviposition activity index (OAI) value of acetone, ethyl acetate, and methanol extracts of Aegle marmelos, Andrographis lineata, and Cocculus hirsutus at 500 ppm were −0.86, −0.87, −0.90, −0.78, −0.87, −0.86, −0.91, −0.94, and −0.86 respectively. The OAI values revealed that
the solvent plant extracts have deterrent effect, and they caused a remarkable negative response resulting in oviposition
of very few eggs. Mean percent hatchability of the ovicidal activity was observed 24 h after treatment. The percent hatchability
was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100% with ethyl
acetate extract of Aegle marmelos, methanol extracts Aegle marmelos, Andrographis lineata, and Cocculus hirsutus were exerted at 1,000 ppm. The maximum repellent activity was observed at 500 ppm in methanol extracts of Aegle marmelos, Andrographis lineata, and ethyl acetate extract of Cocculus hirsutus, and the mean complete protection time ranged from 90 to 120 min with the different extracts tested. These results suggest
that the leaf extracts of Aegle marmelos, Andrographis lineata, and Cocculus hirsutus have the potential to be used as an ideal ecofriendly approach for the control of the Anopheles subpictus. Therefore, this study provides first report on the oviposition, ovicidal, and repellent activities against malaria vector,
Anopheles subpictus of plant extracts from Southern India. 相似文献
18.
Mosquito larvicidal activity of oleic and linoleic acids isolated from Citrullus colocynthis (Linn.) Schrad 总被引:9,自引:9,他引:0
In mosquito control programs, botanical origin may have the potential to be used successfully as larvicides. The larvicidal
activity of crude acetone, hexane, ethyl acetate, methanol, and petroleum ether extracts of the leaf of Centella asiatica Linn., Datura metal Linn., Mukia scabrella Arn., Toddalia asiatica (Linn.) Lam, extracts of whole plant of Citrullus colocynthis (Linn.) Schrad, and Sphaeranthus indicus Linn. were assayed for their toxicity against the early fourth instar larvae of Culex quinquefasciatus (Diptera: Culicidae). The larval mortality was observed after 24 h exposure. All extracts showed moderate larvicidal effects;
however, the highest larval mortality was found in whole plant petroleum ether extract of C. colocynthis. In the present study, bioassay-guided fractionation of petroleum ether extract led to the separation and identification
of fatty acids; oleic acid and linoleic acid were isolated and identified as mosquito larvicidal compounds. Oleic and Linoleic
acids were quite potent against fourth instar larvae of Aedes aegypti L. (LC50 8.80, 18.20 and LC90 35.39, 96.33 ppm), Anopheles stephensi Liston (LC50 9.79, 11.49 and LC90 37.42, 47.35 ppm), and Culex quinquefasciatus Say (LC50 7.66, 27.24 and LC90 30.71, 70.38 ppm). The structure was elucidated from infrared, ultraviolet, 1H-nuclear magnetic resonance, 13C-NMR, and mass spectral data. This is the first report on the mosquito larvicidal activity of the reported isolated compounds
from C. colocynthis. 相似文献
19.
Larvicides play a vital role in controlling mosquitoes in their breeding sites. The present study was carried out to establish
the larvicidal activities of mycosynthesized silver nanoparticles (AgNPs) against vectors: Aedes aegypti and Anopheles stephensi responsible for diseases of public health importance. The AgNPs synthesized by filamentous fungus Cochliobolus lunatus, characterized by UV–Vis spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron
microscopy, and transmission electron microscopy. The characterization studies confirmed the spherical shape and size (3–21 nm)
of silver nanoparticles. The efficacy of mycosynthesized AgNPs at all the tested concentrations (10, 5, 2.5, 1.25, 0.625,
and 0.3125 ppm) against second, third, and fourth instar larvae of A. aegypti (LC50 1.29, 1.48, and 1.58; LC90 3.08, 3.33, and 3.41 ppm) and against A. stephensi (LC50 1.17, 1.30, and 1.41; LC90 2.99, 3.13, and 3.29 ppm) were observed, respectively. The mortality rates were positively correlated with the concentration
of AgNPs. Significant (P < 0.05) changes in the larval mortality was also recorded between the period of exposure against fourth instar larvae of
A. aegypti and A. stephensi. The possible larvicidal activity may be due to penetration of nanoparticles through membrane. Toxicity studies carried out
against non-target fish species Poecilia reticulata, the most common organism in the habitats of A. aegypti and A. stephensi showed no toxicity at LC50 and LC90 doses of the AgNPs. This is the first report on mosquito larvicidal activity of mycosynthesized
nanoparticles. Thus, the use of fungus C. lunatus to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach and the AgNps formed can be potential
mosquito larvicidal agents. 相似文献
20.
The larvicidal activity of crude petroleum ether, ethyl acetate, and methanol extracts of the whole plants of Phryma leptostachya L. was assayed for its toxicity against the early fourth instar larvae of Culex pipiens pallens. The larval mortality was observed after 24 h of exposure. Among three solvent extracts from Phyrma leptostachya L., the petroleum ether extract exhibited the best larvicidal activity. The corresponding LC50 values of petroleum ether, ethyl acetate, and methanol extracts were 3.23, 5.23, and 61.86 ppm against the early fourth instar
larvae of Culex pipiens pallens. The petroleum ether extract was successively subjected to column chromatography and preparative high performance liquid
chromatography, and yielded the three lignans, phrymarolin-I, haedoxane A, and haedoxane E, which were isolated and identified
as new mosquito larvicidal compounds. Phrymarolin-I, haedoxane A, and haedoxane E showed high larvicidal activity, for which
the lethal doses LC50 were estimated at 1.21, 0.025, and 0.15 ppm against the early fourth instar larvae of Culex pipiens pallens, respectively. The structures were elucidated by analyses of IR, UV, MS, and NMR spectral data. This is the first report
on the mosquito larvicidal activity of the three compounds, phrymarolin-I, haedoxane A, and haedoxane E from Phyrma leptostachya L. 相似文献