Anjali Rawani - Academia.edu (original) (raw)

Papers by Anjali Rawani

Jordan journal of pharmaceutical sciences, Mar 19, 2024

Deleted Journal, Jan 20, 2024

Natural Product Research, Feb 19, 2018

PubMed, Aug 1, 2014

Background & objectives: Indiscriminate use of synthetic pesticides has created serious problem f... more Background & objectives: Indiscriminate use of synthetic pesticides has created serious problem for the aquatic flora and fauna, and also resulted in appearance of pesticide resistance in vector population. This study was designed to evaluate the biocontrol efficacy of aqueous and solvent extracts of mature leaves of Solanum nigrum L., against fresh water snail Lymnaea acuminata f. rufescens (Gray) (an intermediate host of parasites causing fasciolopsiasis) and larvae of Culex vishnui group (Reuben) (vector of Japanese encephalitis). Methods: Aqueous and solvent extracts of fresh, mature, green/shed dried leaves of S. nigrum were tested against adult L. acuminata and larvae of Cx. vishnui group. The lethal concentration was determined and the appropriate lethal concentration at 24 h of benzene extract was also studied on non target organisms such as Daphnia sp, Diplonychus annulatum and Chironomus circumdatus. A qualitative phytochemical analysis was carried out in search of active ingredient and the chemical nature of the active substance was also evaluated by infrared (IR) analysis. Results: In a 72 h bioassay experiment with the aqueous extract, the highest mortality was recorded in 0.5 and 3 per cent extract against larvae of Cx. vishnui group and L. acuminata, respectivela. In the benzene solvent extract, the maximum mortality was recorded at a concentration of 150 ppm against L. acuminata and at 50 ppm against larvae of Cx. vishnui group with LC 50 values of 55.45 and 11.59 ppm, respectively at 72 h. The log probit analysis (95% confidence level) recorded lowest value at 72 h of exposure. Qualitative phytochemical analysis reported the presence of some biochemical compounds, such as saponin, flavonoids, steroid and tannin. Among these, the toxic compound was detected by IR analysis having Rf=0.87 (showed 66.70% and 76.70% mortality of L. acuminata and larvae of Cx. vishnui group, respectively). IR analysis provided preliminary information about the aliphatic amide nature of the active ingredient. Interpretation & conclusions: The study results provide considerable scope in exploiting local indigenous plant resources for molluscicidal and mosquito larvicidal activities.

Environmental Science: an Indian journal, 2012

Journal of Mosquito Research, 2016

The purpose of present study was to determine the larvicidal activity of different solvent extrac... more The purpose of present study was to determine the larvicidal activity of different solvent extracts of fruits of Acacia auriculiformis against the 3 rd larval instar of Culex vishnui group. The solvent extracts of fruits of A. auriculiformis (concentrations were 100, 200, 300 ppm) showed varied results against 3 rd larval instars with highest mortality at 300 ppm. The percent mortality was higher in chloroform: methanol (1:1 v/v) extract than other extracts. The order of efficacy of different solvent extracts was chloroform: methanol (1:1 v/v) > absolute alcohol > n-Hexane > acetone > petroleum ether. Results of regression analyses showed that percentage mortalities were positively correlated with the concentrations. Probit analysis revealed LC 50 value and their LCL and UCL values at different time intervals and the lowest LC 50 value was obtained at 72 h of exposures. There was no mortality of non-target organisms after 24 h of exposure to lethal concentration (LC 50 value of chloroform: methanol (1:1 v/v) solvent extract at 24 h determined against 3rd instar larvae).

Parasitology Research, Oct 25, 2014

The present study was carried out to investigate the biocontrol potentiality of active ingredient... more The present study was carried out to investigate the biocontrol potentiality of active ingredient isolated from ethyl acetate extract of mature leaves of Solanum nigrum L. (Solanaceae) against the larval form of Culex quinquefasciatus Say. Mortality rate at a concentration of 25 mg/L of the active compound was highest (P < 0.05) amongst all tested concentrations. Result of log-probit analysis (at 95% confidence level) revealed that LC₅₀ and LC₉₀ values are inversely proportional to exposure period of bioassay. A clear dose-dependent mortality was observed, as the rate of mortality (Y) was positively correlated with the concentrations of the compound (X); having regression coefficient value close to 1. The compound was found to be ecofriendly as it did not show any adverse effect to the studied nontarget organisms. Chemical characterization of the active ingredient was also carried out by infrared spectroscopic analysis (IR), mass analyses (GC-MS) and carbon-hydrogen-nitrogen-sulphur analyses (CHNS), that revealed the presence of a glucosinolate compound [1-thio-ß-D-glucopyranose-1-[(R)-3-hydroxy-2-ethyl-N-hydroxysulfonyloxy propanimidate] having the molecular formula of C₁₁H₂₁NO₁₀S₂.

Proceedings of the Zoological Society, Oct 3, 2022

Journal of Mosquito Research, 2016

Different concentrations of crude and different solvents viz., n-hexane, ethyl acetate, and metha... more Different concentrations of crude and different solvents viz., n-hexane, ethyl acetate, and methanol fruit peel extracts of Citrus limetta Risso ( C. limetta ) were taken for investigation for larvicidal activity against Culex quinquefasciatus Say, 1823 ( Cx. quinquefasciatus ) mosquito species. Crude extract showed good larvicidal activity with very low concentrations against 1 st - 4 th instars larvae. Only 3 rd instar larvae were taken for larvicidal bioassay experiments for each solvent extract. LC 50 values of n-hexane, ethyl acetate, and methanol fruit peel extracts of C. limetta were 661.27, 1268, and 939.43 ppm respectively after 24 h of exposure. No mortality was observed on control treatments. Log probit analyses, regression equations, and R 2 values of larvicidal bioassay experiments with crude and different solvent extracts were determined. Statistical justification was done through ANOVA analyses. Qualitative phytochemical analyses were carried out and detected different secondary metabolites. No mortality was observed on tested non target organisms.

DOAJ (DOAJ: Directory of Open Access Journals), Jul 1, 2014

Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants ... more Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants may be sources of alternative mosquito control agents. The present study was carried out to assess the role of larvicidal activities of the crude extracts of four plants viz. Alternanthera sessilis L. (Amaranthaceae), Trema orientalis L. (Cannabaceae), Gardenia carinata Smith. (Rubiaceae) and Ruellia tuberosa L. (Acanthaceae) against Culex quinquefasciatus Say in laboratory bioassay. Selective concentrations (0.5, 1 and 1.5%) of crude extract of all four plant leaves were tested against I st to IV th instar larvae of Cx. quinquefasciatus. Log probit analysis (at 95% confidence level) revealed the LC50 values. Preliminary qualitative phytochemical analyses of crude extracts were also done. The lethal concentrations (%) of crude extracts at 24 h against III rd instar larvae were also studied on non-target organisms. In a 72 h bioassay experiment with crude extract, the highest mortality was recorded in 1.5 per cent extract. A. sessilis showed the highest mortality (76.7%) at 1.5 per cent crude extract against II nd instar larvae having LC50 value of 0.35 per cent, followed by R. tuberosa (LC50 = 1.84%), G. carinata (LC50 = 2.11) and T. orientalis (LC50 = 2.95%). The regression equation showed a dose-dependent mortality, as the rate of mortality (Y) was positively correlated with the concentration (X). Phytochemical analysis of the crude extract showed the presence of many bioactive phytochemicals such as steroids, alkaloids, terpenes, saponins, etc. No changes in the swimming behaviour and survivality of non-target organism were noticed at the studied concentrations. Crude extract of the four selected plants showed larvicidal activity against Cx. quinquefasciatus. The extracts at the studied concentrations did not produce any harmful effect on non-target organisms.

International Journal of Zoological Investigations

As a vector, mosquitoes are responsible for transmitting deadly diseases such as Chikungunya feve... more As a vector, mosquitoes are responsible for transmitting deadly diseases such as Chikungunya fever, filariasis, encephalitis, West Nile Virus infection, malaria, yellow fever, dengue fever, etc. To combat this problem, various techniques and strategies had been adopted to control the mosquito population. An alternative mosquito control strategy was available from ancient times that is the application of active toxic agents from plant extracts. This preference has several advantages over the consistent application of synthetic insecticides which cause resistance in vector species, harmful effects on environment and non-target organisms, including human health. From ancient times, plants have been used to control the vector mosquitoes, and still now, in many parts of the world, many researchers are looking for plant substances to kill the mosquitoes or cause repellency in mosquitoes. The phytochemicals that originate from the plant showed various activities such as larval mortality, d...

Journal of Mosquito Research, 2012

International Journal of Mosquito Research

Proceedings of the Zoological Society, Oct 3, 2022

Parasitology Research, 2014

The present study was carried out to investigate the biocontrol potentiality of active ingredient... more The present study was carried out to investigate the biocontrol potentiality of active ingredient isolated from ethyl acetate extract of mature leaves of Solanum nigrum L. (Solanaceae) against the larval form of Culex quinquefasciatus Say. Mortality rate at a concentration of 25 mg/L of the active compound was highest (P < 0.05) amongst all tested concentrations. Result of log-probit analysis (at 95% confidence level) revealed that LC₅₀ and LC₉₀ values are inversely proportional to exposure period of bioassay. A clear dose-dependent mortality was observed, as the rate of mortality (Y) was positively correlated with the concentrations of the compound (X); having regression coefficient value close to 1. The compound was found to be ecofriendly as it did not show any adverse effect to the studied nontarget organisms. Chemical characterization of the active ingredient was also carried out by infrared spectroscopic analysis (IR), mass analyses (GC-MS) and carbon-hydrogen-nitrogen-sulphur analyses (CHNS), that revealed the presence of a glucosinolate compound [1-thio-ß-D-glucopyranose-1-[(R)-3-hydroxy-2-ethyl-N-hydroxysulfonyloxy propanimidate] having the molecular formula of C₁₁H₂₁NO₁₀S₂.

Asian Pacific Journal of Tropical Biomedicine, 2011

Page 1. S71 Document heading Evaluation of antimicrobial properties of four plant extracts agains... more Page 1. S71 Document heading Evaluation of antimicrobial properties of four plant extracts against human pathogens Anjali Rawani, Sudin Pal, GoutamChandra* Department of Zoology, Mosquito and Microbiology Research Units, University of Burdwan, West Bengal, India ...

Parasitology Research, 2010

The present study was carried out to establish the larvicidal activities of crude and solvent ext... more The present study was carried out to establish the larvicidal activities of crude and solvent extracts of Solanum nigrum L. leaves against Culex quinquefasciatus Say as target species. The results indicated that the mortality rates at 0.5% concentration were highest amongst all concentrations of the crude extracts tested against all the larval instars at 24, 48 and 72 h of exposure. Result of log probit analysis (at 95% confidence level) revealed that lethal concentration LC(50) and LC(90) values gradually decreased with the exposure periods in bioassay experiment with the crude plant extract. The results of regression analysis of crude extract of S. nigrum revealed that the mortality rate is positively correlated with the concentration of the extracts. Mature leaves of S. nigrum were also extracted with six different solvents [viz. petroleum ether, benzene, ethyl acetate, chloroform: methanol (1:1 v/v), acetone and absolute alcohol] to determine the best extractant for subsequent isolation and characterization of active ingredient. Mortality rate with ethyl acetate extract was significantly higher (p < 0.05) than other extracts when 50-ppm doses were used. The corresponding LC(50) value of acetone, absolute alcohol, petroleum ether, chloroform: methanol (1:1 v/v), benzene and ethyl acetate extracts were 72.91 ppm, 59.81 ppm, 54.11 ppm, 32.69 ppm, 27.95 ppm and 17.04 ppm, respectively, after 24 h of exposure period. Results of this study show that the ethyl acetate extract of S. nigrum may be considered as a potent source of a mosquito larvicidal agent.

Parasitology Research, 2009

The present study was carried out to establish the larvicidal properties of crude extracts of thr... more The present study was carried out to establish the larvicidal properties of crude extracts of three plants, viz. Carica papaya, Murraya paniculata and Cleistanthus collinus against Culex quinquefasciatus as target species. The relative efficacy of the plant extracts in vector control was as follows: C. papaya seed extract > M. paniculata fruit extract > M. paniculata leaf extract > C. collinus leaf extract. Result of log-probit analysis (at 95% confidence level) revealed that LC(50) and LC(95) values gradually decreased with the exposure periods similar to the result in bioassay experiment for each of the plant extract. The results of preliminary qualitative phytochemical analysis of all the plants revealed the presence of many bioactive principles such as steroids, alkaloids, terpenes, saponins, etc. that may be responsible for their biocontrol potentiality. The appropriate lethal concentrations at 24 h for each of the extracts were also studied on non-target organisms such as Diplonychus annulatum and Chironomus circumdatus, and no change in the swimming behaviour and survivality was noticed, which indicates that all the extracts are safe for the aquatic ecosystem.

Acta Tropica, 2013

Silver nanoparticles (AgNPs) that are synthesized by using aqueous extracts of Solanum nigrum L.,... more Silver nanoparticles (AgNPs) that are synthesized by using aqueous extracts of Solanum nigrum L., is a simple, non-toxic and ecofriendly green material. The present study is based on assessments of the larvicidal and antimicrobial activities of the synthesized AgNPs from fresh leaves, dry leaves and green berries of S. nigrum against larvae of Culex quinquefasciatus and Anopheles stephensi and four human pathogenic and five fish pathogenic bacteria respectively. The synthesized nanoparticles are characterized with UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM) analysis. The nanoparticles are spherical to polyhedral in shape with size of 50-100 nm (average size of 56.6 nm). In larvicidal bioassay with synthesized AgNPs, highest mortality are observed at 10 ppm against An. stephensi with LC 50 values of 1.33, 1.59, 1.56 ppm and LC 90 values of 3.97, 7.31, 4.76 ppm for dry leaves, fresh leaves and berries respectively. Antibacterial activity test reveals better results against fish pathogenic bacteria than human pathogenic bacteria. Non target organism like Toxorhynchites larvae (mosquito predator), Diplonychus annulatum (predatory water-bug) and Chironomus circumdatus larvae (chironomid) are also exposed to respective lethal concentrations (to mosquito larvae) of dry nanoparticles and no abnormality in the non target organisms are recorded. These results suggest that the synthesized AgNPs of S. nigrum have the potential to be used as an ideal eco-friendly compound for the control of the mosquito larvae and harmful bacteria.

Jordan journal of pharmaceutical sciences, Mar 19, 2024

Deleted Journal, Jan 20, 2024

Natural Product Research, Feb 19, 2018

PubMed, Aug 1, 2014

Background & objectives: Indiscriminate use of synthetic pesticides has created serious problem f... more Background & objectives: Indiscriminate use of synthetic pesticides has created serious problem for the aquatic flora and fauna, and also resulted in appearance of pesticide resistance in vector population. This study was designed to evaluate the biocontrol efficacy of aqueous and solvent extracts of mature leaves of Solanum nigrum L., against fresh water snail Lymnaea acuminata f. rufescens (Gray) (an intermediate host of parasites causing fasciolopsiasis) and larvae of Culex vishnui group (Reuben) (vector of Japanese encephalitis). Methods: Aqueous and solvent extracts of fresh, mature, green/shed dried leaves of S. nigrum were tested against adult L. acuminata and larvae of Cx. vishnui group. The lethal concentration was determined and the appropriate lethal concentration at 24 h of benzene extract was also studied on non target organisms such as Daphnia sp, Diplonychus annulatum and Chironomus circumdatus. A qualitative phytochemical analysis was carried out in search of active ingredient and the chemical nature of the active substance was also evaluated by infrared (IR) analysis. Results: In a 72 h bioassay experiment with the aqueous extract, the highest mortality was recorded in 0.5 and 3 per cent extract against larvae of Cx. vishnui group and L. acuminata, respectivela. In the benzene solvent extract, the maximum mortality was recorded at a concentration of 150 ppm against L. acuminata and at 50 ppm against larvae of Cx. vishnui group with LC 50 values of 55.45 and 11.59 ppm, respectively at 72 h. The log probit analysis (95% confidence level) recorded lowest value at 72 h of exposure. Qualitative phytochemical analysis reported the presence of some biochemical compounds, such as saponin, flavonoids, steroid and tannin. Among these, the toxic compound was detected by IR analysis having Rf=0.87 (showed 66.70% and 76.70% mortality of L. acuminata and larvae of Cx. vishnui group, respectively). IR analysis provided preliminary information about the aliphatic amide nature of the active ingredient. Interpretation & conclusions: The study results provide considerable scope in exploiting local indigenous plant resources for molluscicidal and mosquito larvicidal activities.

Environmental Science: an Indian journal, 2012

Journal of Mosquito Research, 2016

The purpose of present study was to determine the larvicidal activity of different solvent extrac... more The purpose of present study was to determine the larvicidal activity of different solvent extracts of fruits of Acacia auriculiformis against the 3 rd larval instar of Culex vishnui group. The solvent extracts of fruits of A. auriculiformis (concentrations were 100, 200, 300 ppm) showed varied results against 3 rd larval instars with highest mortality at 300 ppm. The percent mortality was higher in chloroform: methanol (1:1 v/v) extract than other extracts. The order of efficacy of different solvent extracts was chloroform: methanol (1:1 v/v) > absolute alcohol > n-Hexane > acetone > petroleum ether. Results of regression analyses showed that percentage mortalities were positively correlated with the concentrations. Probit analysis revealed LC 50 value and their LCL and UCL values at different time intervals and the lowest LC 50 value was obtained at 72 h of exposures. There was no mortality of non-target organisms after 24 h of exposure to lethal concentration (LC 50 value of chloroform: methanol (1:1 v/v) solvent extract at 24 h determined against 3rd instar larvae).

Parasitology Research, Oct 25, 2014

The present study was carried out to investigate the biocontrol potentiality of active ingredient... more The present study was carried out to investigate the biocontrol potentiality of active ingredient isolated from ethyl acetate extract of mature leaves of Solanum nigrum L. (Solanaceae) against the larval form of Culex quinquefasciatus Say. Mortality rate at a concentration of 25 mg/L of the active compound was highest (P < 0.05) amongst all tested concentrations. Result of log-probit analysis (at 95% confidence level) revealed that LC₅₀ and LC₉₀ values are inversely proportional to exposure period of bioassay. A clear dose-dependent mortality was observed, as the rate of mortality (Y) was positively correlated with the concentrations of the compound (X); having regression coefficient value close to 1. The compound was found to be ecofriendly as it did not show any adverse effect to the studied nontarget organisms. Chemical characterization of the active ingredient was also carried out by infrared spectroscopic analysis (IR), mass analyses (GC-MS) and carbon-hydrogen-nitrogen-sulphur analyses (CHNS), that revealed the presence of a glucosinolate compound [1-thio-ß-D-glucopyranose-1-[(R)-3-hydroxy-2-ethyl-N-hydroxysulfonyloxy propanimidate] having the molecular formula of C₁₁H₂₁NO₁₀S₂.

Proceedings of the Zoological Society, Oct 3, 2022

Journal of Mosquito Research, 2016

Different concentrations of crude and different solvents viz., n-hexane, ethyl acetate, and metha... more Different concentrations of crude and different solvents viz., n-hexane, ethyl acetate, and methanol fruit peel extracts of Citrus limetta Risso ( C. limetta ) were taken for investigation for larvicidal activity against Culex quinquefasciatus Say, 1823 ( Cx. quinquefasciatus ) mosquito species. Crude extract showed good larvicidal activity with very low concentrations against 1 st - 4 th instars larvae. Only 3 rd instar larvae were taken for larvicidal bioassay experiments for each solvent extract. LC 50 values of n-hexane, ethyl acetate, and methanol fruit peel extracts of C. limetta were 661.27, 1268, and 939.43 ppm respectively after 24 h of exposure. No mortality was observed on control treatments. Log probit analyses, regression equations, and R 2 values of larvicidal bioassay experiments with crude and different solvent extracts were determined. Statistical justification was done through ANOVA analyses. Qualitative phytochemical analyses were carried out and detected different secondary metabolites. No mortality was observed on tested non target organisms.

DOAJ (DOAJ: Directory of Open Access Journals), Jul 1, 2014

Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants ... more Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants may be sources of alternative mosquito control agents. The present study was carried out to assess the role of larvicidal activities of the crude extracts of four plants viz. Alternanthera sessilis L. (Amaranthaceae), Trema orientalis L. (Cannabaceae), Gardenia carinata Smith. (Rubiaceae) and Ruellia tuberosa L. (Acanthaceae) against Culex quinquefasciatus Say in laboratory bioassay. Selective concentrations (0.5, 1 and 1.5%) of crude extract of all four plant leaves were tested against I st to IV th instar larvae of Cx. quinquefasciatus. Log probit analysis (at 95% confidence level) revealed the LC50 values. Preliminary qualitative phytochemical analyses of crude extracts were also done. The lethal concentrations (%) of crude extracts at 24 h against III rd instar larvae were also studied on non-target organisms. In a 72 h bioassay experiment with crude extract, the highest mortality was recorded in 1.5 per cent extract. A. sessilis showed the highest mortality (76.7%) at 1.5 per cent crude extract against II nd instar larvae having LC50 value of 0.35 per cent, followed by R. tuberosa (LC50 = 1.84%), G. carinata (LC50 = 2.11) and T. orientalis (LC50 = 2.95%). The regression equation showed a dose-dependent mortality, as the rate of mortality (Y) was positively correlated with the concentration (X). Phytochemical analysis of the crude extract showed the presence of many bioactive phytochemicals such as steroids, alkaloids, terpenes, saponins, etc. No changes in the swimming behaviour and survivality of non-target organism were noticed at the studied concentrations. Crude extract of the four selected plants showed larvicidal activity against Cx. quinquefasciatus. The extracts at the studied concentrations did not produce any harmful effect on non-target organisms.

International Journal of Zoological Investigations

As a vector, mosquitoes are responsible for transmitting deadly diseases such as Chikungunya feve... more As a vector, mosquitoes are responsible for transmitting deadly diseases such as Chikungunya fever, filariasis, encephalitis, West Nile Virus infection, malaria, yellow fever, dengue fever, etc. To combat this problem, various techniques and strategies had been adopted to control the mosquito population. An alternative mosquito control strategy was available from ancient times that is the application of active toxic agents from plant extracts. This preference has several advantages over the consistent application of synthetic insecticides which cause resistance in vector species, harmful effects on environment and non-target organisms, including human health. From ancient times, plants have been used to control the vector mosquitoes, and still now, in many parts of the world, many researchers are looking for plant substances to kill the mosquitoes or cause repellency in mosquitoes. The phytochemicals that originate from the plant showed various activities such as larval mortality, d...

Journal of Mosquito Research, 2012

International Journal of Mosquito Research

Proceedings of the Zoological Society, Oct 3, 2022

Parasitology Research, 2014

The present study was carried out to investigate the biocontrol potentiality of active ingredient... more The present study was carried out to investigate the biocontrol potentiality of active ingredient isolated from ethyl acetate extract of mature leaves of Solanum nigrum L. (Solanaceae) against the larval form of Culex quinquefasciatus Say. Mortality rate at a concentration of 25 mg/L of the active compound was highest (P < 0.05) amongst all tested concentrations. Result of log-probit analysis (at 95% confidence level) revealed that LC₅₀ and LC₉₀ values are inversely proportional to exposure period of bioassay. A clear dose-dependent mortality was observed, as the rate of mortality (Y) was positively correlated with the concentrations of the compound (X); having regression coefficient value close to 1. The compound was found to be ecofriendly as it did not show any adverse effect to the studied nontarget organisms. Chemical characterization of the active ingredient was also carried out by infrared spectroscopic analysis (IR), mass analyses (GC-MS) and carbon-hydrogen-nitrogen-sulphur analyses (CHNS), that revealed the presence of a glucosinolate compound [1-thio-ß-D-glucopyranose-1-[(R)-3-hydroxy-2-ethyl-N-hydroxysulfonyloxy propanimidate] having the molecular formula of C₁₁H₂₁NO₁₀S₂.

Asian Pacific Journal of Tropical Biomedicine, 2011

Page 1. S71 Document heading Evaluation of antimicrobial properties of four plant extracts agains... more Page 1. S71 Document heading Evaluation of antimicrobial properties of four plant extracts against human pathogens Anjali Rawani, Sudin Pal, GoutamChandra* Department of Zoology, Mosquito and Microbiology Research Units, University of Burdwan, West Bengal, India ...

Parasitology Research, 2010

The present study was carried out to establish the larvicidal activities of crude and solvent ext... more The present study was carried out to establish the larvicidal activities of crude and solvent extracts of Solanum nigrum L. leaves against Culex quinquefasciatus Say as target species. The results indicated that the mortality rates at 0.5% concentration were highest amongst all concentrations of the crude extracts tested against all the larval instars at 24, 48 and 72 h of exposure. Result of log probit analysis (at 95% confidence level) revealed that lethal concentration LC(50) and LC(90) values gradually decreased with the exposure periods in bioassay experiment with the crude plant extract. The results of regression analysis of crude extract of S. nigrum revealed that the mortality rate is positively correlated with the concentration of the extracts. Mature leaves of S. nigrum were also extracted with six different solvents [viz. petroleum ether, benzene, ethyl acetate, chloroform: methanol (1:1 v/v), acetone and absolute alcohol] to determine the best extractant for subsequent isolation and characterization of active ingredient. Mortality rate with ethyl acetate extract was significantly higher (p < 0.05) than other extracts when 50-ppm doses were used. The corresponding LC(50) value of acetone, absolute alcohol, petroleum ether, chloroform: methanol (1:1 v/v), benzene and ethyl acetate extracts were 72.91 ppm, 59.81 ppm, 54.11 ppm, 32.69 ppm, 27.95 ppm and 17.04 ppm, respectively, after 24 h of exposure period. Results of this study show that the ethyl acetate extract of S. nigrum may be considered as a potent source of a mosquito larvicidal agent.

Parasitology Research, 2009

The present study was carried out to establish the larvicidal properties of crude extracts of thr... more The present study was carried out to establish the larvicidal properties of crude extracts of three plants, viz. Carica papaya, Murraya paniculata and Cleistanthus collinus against Culex quinquefasciatus as target species. The relative efficacy of the plant extracts in vector control was as follows: C. papaya seed extract > M. paniculata fruit extract > M. paniculata leaf extract > C. collinus leaf extract. Result of log-probit analysis (at 95% confidence level) revealed that LC(50) and LC(95) values gradually decreased with the exposure periods similar to the result in bioassay experiment for each of the plant extract. The results of preliminary qualitative phytochemical analysis of all the plants revealed the presence of many bioactive principles such as steroids, alkaloids, terpenes, saponins, etc. that may be responsible for their biocontrol potentiality. The appropriate lethal concentrations at 24 h for each of the extracts were also studied on non-target organisms such as Diplonychus annulatum and Chironomus circumdatus, and no change in the swimming behaviour and survivality was noticed, which indicates that all the extracts are safe for the aquatic ecosystem.

Acta Tropica, 2013

Silver nanoparticles (AgNPs) that are synthesized by using aqueous extracts of Solanum nigrum L.,... more Silver nanoparticles (AgNPs) that are synthesized by using aqueous extracts of Solanum nigrum L., is a simple, non-toxic and ecofriendly green material. The present study is based on assessments of the larvicidal and antimicrobial activities of the synthesized AgNPs from fresh leaves, dry leaves and green berries of S. nigrum against larvae of Culex quinquefasciatus and Anopheles stephensi and four human pathogenic and five fish pathogenic bacteria respectively. The synthesized nanoparticles are characterized with UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM) analysis. The nanoparticles are spherical to polyhedral in shape with size of 50-100 nm (average size of 56.6 nm). In larvicidal bioassay with synthesized AgNPs, highest mortality are observed at 10 ppm against An. stephensi with LC 50 values of 1.33, 1.59, 1.56 ppm and LC 90 values of 3.97, 7.31, 4.76 ppm for dry leaves, fresh leaves and berries respectively. Antibacterial activity test reveals better results against fish pathogenic bacteria than human pathogenic bacteria. Non target organism like Toxorhynchites larvae (mosquito predator), Diplonychus annulatum (predatory water-bug) and Chironomus circumdatus larvae (chironomid) are also exposed to respective lethal concentrations (to mosquito larvae) of dry nanoparticles and no abnormality in the non target organisms are recorded. These results suggest that the synthesized AgNPs of S. nigrum have the potential to be used as an ideal eco-friendly compound for the control of the mosquito larvae and harmful bacteria.