Abstract
Objective
To determine the repellent and pupicidal activities of Pogostemon cablin (P. cablin) chemical compositions were assayed for their toxicity against selected important vector mosquitoes, viz., Aedes aegypti (Ae. aegypti), Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus) (Diptera: Culicidae).
Methods
The plants dry aerial parts were subjected to hydrodistillation using a modified Clevenger-type apparatus. The composition of the essential oil was analyzed by Gas Chromatography (GC) and GC mass spectrophotometry. Evaluation was carried out in a net cage (45 cm×30 cm×45 cm) containing 100 blood starved female mosquitoes and were assayed in the laboratory condition by using the protocol of WHO 2010. The repellent activity of P. cablin chemical compositions at concentration of 2mg/cm2were applied on skin of fore arm in man and exposed against adult female mosquitoes. The pupicidal activity was determined against selected important vector mosquitoes to concentration of 100 mg/L and mortality of each pupa was recorded after 24 h of exposure to the compounds.
Results
Chemical constituents of 15 compounds were identified in the oil of P.cablin compounds representing to 98.96%. The major components in essential oil were â-patchoulene, á-guaiene, ã-patchoulene, á-bulnesene and patchouli alcohol. The repellent activity of patchouli alcohol compound was found to be most effective for repellent activity and 2 mg/cm2 concentration provided 100% protection up to 280 min against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, respectively. Similarly, pupae exposed to 100 mg/L concentrations of P. cablin chemical compositions. Among five compounds tested patchouli alcoholwas found to be most effective for pupicidal activity provided 28.44, 26.28 and 25.36 against Ae.aegypti, An.stephensi and Cx. quinquefasciatus, respectively. The percent adult emergence was inversely proportional to the concentration of compounds and directly proportional to the pupal mortality.
Conclusion
These results suggest that the P. cablin chemical compositions have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This is the first report on the mosquito repellent and pupicidal activities of the reported P. cablin chemical compositions.
Keywords: Aedes aegypti, Anopheles stephensi, Culex quinquefasciatus, Pogostemon cablin, Repellent activity, Pupicidal activity
1. Introduction
Mosquitoes being vector for many tropical and subtropical diseases are the most important single group of insect well known for their public health importance[1]–[3].Mosquito-borne diseases such as malaria, filariasis, dengue, and viral encephalitis contribute to a larger proportion of health problems of developing countries. Repeated use of synthetic insecticides for mosquito control has disrupted natural biological control systems and led to resurgences in mosquito populations. It also resulted in the development of resistance, undesirable effects on non-target organisms, and fostered environmental and human health concern[4]. The drastic effects of chemical insecticide-based intervention measures for the control of disease vectors have received wide public apprehension and have caused many problems like insecticide resistance, resurgence of pest species, environmental pollution, toxic hazards to humans, and other nontarget organisms. To alleviate these problems, major emphasis has been on the use of natural plant-based products as larvicides which can provide an alternate to synthetic insecticides[5],[6].
There is an increased interest in the search for insecticides from natural sources as they are considered safer, more cost effective, biodegradable and are target specific against mosquitoes. Several studies have identified and reported plants and plant extracts effective against mosquitoes at various stages of development. The phytochemicals derived from plant sources possess a complex of chemicals with unique biological activity. The phytochemicals derived from plant resources can act as larvicides, insect growth regulators, repellents, and ovipositional attractants, having deterrent activities observed by different researchers[7],[8],[9],[10], [11],[12]. The use of scientifically proven non-chemical methods and limited use of drug is being considered as safety to environment and human health[13],[14]. The Pogostemon is major genus of the family Lamiaceae. Pogostemon has been used against the common cold and as an antifungal agent in traditional medicine. Lamiaceae herb family consists of more than 252 genus and 7 000 Species. Lamiaceae family is known for the wealth of species with medicinal properties, which have been used since early times and many of these species are common in Mediterranean region. Extensive cultivation of this plant is carried out in Malaysia, Indonesia, India, China, Brazil and Pakistan for its essential oil (patchouli oil). Thus, the constituents of patchouli oil have frequently been investigated, and the presence of a number of monoandsesquiterpenoids has been reported[15],[16]. The aim of the study was to determine the effect of repellent and pupicidal activities of the P. cablin essential oil compounds against the selected vector mosquitoes.
2. Materials and methods
2.1. Plant material and essential oil extraction
The plants fresh aerial parts of P. cablin, collected from the forest region of Ooty, Uthagamandalam District, Tamilnadu, India. the plant material were collected in the month of February 2010, were air dried and essential oil was obtained by hydrodistillation of 5kg of fresh leaves in a clavenger apparatus for 4 h. the distilled oil was dried over anhydrous sodium sulphate and stored under nitrogen atmosphere until further use. The plant material was identified and the voucher specimens were deposited at the department of Zoology, Annamalai University, Annamalai Nagar, Tamilnadu, India.
2.2. Gas Chromatography Analysis
Analysis was carried on a varian-gas chromatograph equipped with a flame ionization detector and a BPI (100% dimethyl polysiloxane) capillary column. Helium at a flow rate of 1.0 mL/min and 8 psi inlet pressure was employed as a carrier gas. Temperature was programmed from 60 to 220 at 5 °C min-1with a final hold time of 6 min. The injector and detector temperatures were maintained at 250 and 300 °C, respectively. The sample (0.2 µL) was injected with 1:20 split ratio.
2.3. Gas Chromatography - Mass Spectrometry Analysis
Gas chromatography - mass spectrometry (GC-MS) analysis was performed on an Agilent 6890 GC equipped with 5973 N mass selective detector and an HP-5 (5% phynylmethylpolysiloxane) capillary column. The oven temperature was programmed from 50 to 280 °C at the rate of 4 /min and held at this temperature for 5 min. The inlet and interface temperatures were 250 and 280 °C, respectively. The carrier gas was helium at a flow rate of 1.0 mL/min (constant flow). The sample (0.2µL) was injected with a split of 20:1. Electron impact mass spectrometry was carried at 70 eV. Ion source and quadrupole temperatures were maintained at 230 and 150 °C respectively.
2.4. Mosquito rearing
The mosquitoes, Ae. aegypti, An. stephensi and Cx. quinquefasciatus, were reared in the Department of Zoology, Annamalai University. The larvae were fed on dog biscuits and yeast powder in the 3:1 ratio. Adults were provided with 10% sucrose solution and one week old chick for blood meal. Mosquitoes were held at (28±2) °C, 70%-85% relative humidity (RH), with a photo period of 14 h light, 10 h dark.
2.5. Repellent activity
The repellent study was following the methods of WHO[17]. 3-4 days old blood-starved female of selected mosquitoes (100) were kept in a net cage (45 cm×45 cm×40cm). The volunteer had no contact with lotions, perfumes or perfumed soaps on the day of the assay. The arms of the test person were cleaned with isopropanol. After air drying the arm only 25 cm2 of the dorsal side of the skin on each arm was exposed, the remaining area being covered by rubber gloves. The P. cablin major chemical compositions were dissolved in 1 mL DMSO and this DMSO served as control. The selected essential oil chemical compositions at 2 mg/cm2 concentration were applied. The control and treated arms were introduced simultaneously into the cage. The numbers of bites were counted over 5 min every 30 min. The experiment was conducted five times. It was observed that there was no skin irritation from the chemical compositions. The percentage protection was calculated by using the following formula.
% Repellency=[(Ta - Tb)/Ta]×100
Where Ta is the number of mosquitoes in the control group and Tb is the number of mosquitoes in the treated group.
2.6. Pupicidal activity
Batches of ten early emerged pupae were introduced into 500 mL of the test medium containing 100mg/L concentration of essential oil chemical compositions in a plastic cups in five replications. In control, the same number of pupae was maintained in 500 mL of dechlorinated water containing appropriate volume of DMSO. All containers were maintained at room temperature with naturally prevailing photoperiod (12: 12h / L: D) in the laboratory. Any pupa was considered to be dead if did not move when prodded repeatedly with a soft brush. Mortality of each pupa was recorded after 24 h of exposure to the selected concentration of chemical compositions following the Abbott formula Abbott[18].
2.7. Statistical Analysis
The data were calculated by using the software statistical package of social science (SPSS) version 13.0 for windows, significance level was set at P<0.05.
3. Results
3.1. Chemical constituent of essential oil
The chemical constituents of the essential oil of P. cablin the retention indices and the percentage of the individual components are summarized in Table 1. The essential oil was obtained from fresh aerial parts of P. cablin hydrodistilled in a clavenger apparatus and was analysed by GC-MS. A total of 15 compounds were detected representing to 98.96%. The major components in essential oil were β-patchoulene (12.88%), α-guaiene (15.44%), γ-patchoulene (11.72%), α-bulnesene (19.49%) and patchouli alcohol (22.62%). The percentage compositions of remaining 10 compounds ranged from 0.22% - 3.58%.
Table 1. Chemical constituents of the essential oil from aerial parts of P. cablin.
| Peak | Compounds | RT(min) * | Concentration (%) leaves |
| 1 | α-pinene | 938 | 0.46 |
| 2 | δ-elemene | 1327 | 1.32 |
| 3 | β-patchoulene | 1380 | 12.88 |
| 4 | β-caryophyllene | 1421 | 2.53 |
| 5 | α-guaiene | 1440 | 15.44 |
| 6 | γ-patchoulene | 1441 | 11.72 |
| 7 | α-patchoulene | 1456 | 3.58 |
| 8 | eremophilene | 1486 | 1.36 |
| 9 | α-bulnesene | 1505 | 19.49 |
| 10 | β-bisabolene | 1509 | 0.22 |
| 11 | t-β-elemenone | 1601 | 2.74 |
| 12 | patchouli alcohol | 1659 | 22.62 |
| 13 | farnesol | 1713 | 1.55 |
| 14 | aromadendrene oxide | 1749 | 1.57 |
| 15 | nonadecane | 1902 | 1.48 |
*RT= Retention time (min).
3.2. Repellent activity of chemical compounds
The results of the repellent activity of chemical compounds of P. cablin against selected important vector mosquitoes, viz., Ae. aegypti, An. stephensi and Cx. quinquefasciatus, are presented in Tables 2. Among five compounds tested, the maximum repellent activity was observed in patchouli alcohol at 2mg/cm2 concentration provided 100% protection up to 280min against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, respectively.
Table 2. Repellent activity of P. cablin essential oil compounds tested against selected vector mosquitoes.
| Compounds | Mosquitoes | Concentration 2mg/cm2, % of repellency |
|||||||
| Time post application of repellent (min) | |||||||||
| 40 | 80 | 120 | 160 | 200 | 240 | 280 | 320 | ||
| γ-patchoulene | Ae. aegypti | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 94.3±2.4 | 88.5±2.2 | 83.2±2.4 | 80.4±1.2 |
| An. stephensi | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 92.6±1.3 | 86.3±1.7 | 79.2±1.8 | 77.2±1.6 | |
| Cx.quinquefasciatus | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 91.6±1.2 | 84.4±1.6 | 76.4±1.6 | 71.8±1.8 | |
| patchouli alcohol | Ae. aegypti | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 98.3±2.2 |
| An. stephensi | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 96.7±1.4 | |
| Cx.quinquefasciatus | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 91.4±2.6 | |
| α-bulnesene | Ae. aegypti | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 98.5±2.0 | 94.3±2.5 |
| An. stephensi | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 95.2±2.2 | 91.6±2.2 | |
| Cx.quinquefasciatus | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 91.2±2.3 | 89.3±1.8 | |
| β-patchoulene | Ae. aegypti | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 98.3±2.5 | 93.3±2.4 | 88.4±1.6 | 85.9±2.8 |
| An. stephensi | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 94.8±1.9 | 88.5±2.8 | 82.2±2.5 | 79.4±1.6 | |
| Cx.quinquefasciatus | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 92.2±1.3 | 84.3±1.7 | 80.5±2.2 | 75.8±1.4 | |
| α-guaiene | Ae. aegypti | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 95.8±2.2 | 88.2±2.6 |
| An. stephensi | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 91.2±2.8 | 84.2±2.3 | |
| Cx.quinquefasciatus | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 100±0.0 | 88.4±1.6 | 82.6±2.6 | |
Each value mean±SD represents mean of six values.
3.3. Pupicidal activity of chemical compounds
The pupicidal activity of Ae. aegypti, An. stephensi and Cx. quinquefasciatus, were tested with five different compounds of P. cablin at 100 mg/L concentration, and the results are listed in Table 3. The percent adult emergence was inversely proportional to the concentration of compounds and directly proportional to the pupal mortality. Among the five different compounds tested for pupicidal activity against selected vector mosquitoes, the patchouli alcohol was found to be most effective for pupicidal activity provided 28.44, 26.28 and 25.36 against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, respectively.
Table 3. Pupicidal activity of Pogostemon cablin essential oil compounds tested against selected vector mosquitoes.
| Compounds | Mosquitoes | Concentration 100mg/L, 24 h of exposure period |
||||
| Mortality* |
Adult emergence |
|||||
| Pupal mortality | % Mortality | Adult | % Emergence | |||
| γ-patchoulene | Ae. aegypti | 24.25±1.52i | 80.83 | 5.75±1.86i | 19.16 | |
| An. stephensi | 22.46±1.46f | 74.86 | 7.54±1.64l | 25.13 | ||
| Cx.quinquefasciatus | 21.22±1.82c | 70.73 | 8.78±1.22o | 29.26 | ||
| patchouli alcohol | Ae. aegypti | 28.44±1.35p | 94.80 | 1.56±1.48b | 5.20 | |
| An. stephensi | 26.28±1.33m | 87.60 | 3.72±1.62e | 12.40 | ||
| Cx.quinquefasciatus | 25.36±1.42l | 84.53 | 4.64±1.66f | 15.46 | ||
| α-bulnesene | Ae. aegypti | 27.25±1.83o | 90.83 | 2.57±1.32c | 9.16 | |
| An. stephensi | 24.64±1.44j | 82.13 | 5.36±1.52h | 17.86 | ||
| Cx.quinquefasciatus | 23.86±1.65h | 79.53 | 6.14±1.64j | 20.46 | ||
| β-patchoulene | Ae. aegypti | 25.18±1.22k | 83.93 | 4.82±1.66g | 16.06 | |
| An. stephensi | 21.83±1.37e | 72.76 | 8.17±1.72m | 27.23 | ||
| Cx.quinquefasciatus | 20.24±1.62b | 67.46 | 9.76±1.45p | 32.53 | ||
| α-guaiene | Ae. aegypti | 26.38±1.24n | 87.93 | 3.62±1.36d | 12.06 | |
| An. stephensi | 23.22±1.83g | 77.40 | 6.78±1.84k | 22.60 | ||
| Cx.quinquefasciatus | 21.64±1.75d | 72.13 | 8.36±1.63n | 27.86 | ||
| Control group | Selected mosquitoes | 0.0±0.0a | 0.0 | 0.0±0.0a | 0.0 | |
Value represents mean±SD of five replications. *Mortality of the pupae observed after 24 h of exposure period. Values in the column with a different superscript alphabet are significantly different at P<0.05 level DMRT Test.
4. Discussion
In our results showed that, chemical constituents of the essential oil of P. cablin have significant repellant and pupicidal activity against Ae. aegypti, An. stephensi and Cx. quinquefasciatus mosquito. The results are comparable with an earlier report by Eliningaya et al reported that mortality of Cx. quinquefasciatus ranged from 0.50% to 96.75% while for An. gambiaes. It was from 13.75% to 97.91%[19]. In the semi- field experiments, the mortality rates observed varied for both species with time and concentrations. The LC50 and LC95 value in the laboratory was similar for both species while in the semi- field they were different for each. In wild, adult mosquitoes, the KT50 for S. terebinthifolia was 11.29 min while for alphacypermethrin was 19.34 min. The 24 h mortality was found to be 100.0% for S. terebinthifolia and 75.0% for alphacypermethrin which was statistically significant.The larvicidal activity of petroleum ether, ethanolic, aqueous extracts of dried leaves, and fixed oil from the seeds of Caesalpinia bonduc showed 100% mortality in 1% concentration of petroleum ether and ethanolic extract of leaf, whereas it was 55% in 2.5% concentration of aqueous extract and 92.6% in 2.5% concentration of fixed oil against the fourth instar larvae of Cx. quinquefasciatus[20]. The methanol extract of Ervatamia coronaria showed promising larvicidal and ovicidal activity agains An. stephensi. The direct and indirect contributions of such effects to treatment efficacy through reduced larval feeding and fitness need to be properly understood in order to improve the use of botanical insecticides for management of An. Stephensi[21]. The petroleum ether extract of Solanum xanthocarpum was observed to be the most toxic with LC50 of 1.41 and 0.93 mg/L and LC90 of 16.94 and 8.48 mg/L at 24 and 48 h after application, respectively, against An. Stephensi[22]. Govindarajan and Karuppannan[23] reported that The LC50 values of benzene, hexane, ethyl acetate, methanol and chloroform extract of E. alba against early third instar larvae of Ae. Aegypti, respectively. Maximum larvicidal activity was observed in the methanol extract followed by chloroform, benzene, ethyl acetate and hexane as well as most ovicidal activity was fond in methanol extract of E. alba against eggs of Ae. Aegypti 100% mortality recorded.
Bagavan et al[24]have reported that peel chloroform extract of Citrus sinensis, leaf ethyl acetate extracts of Ocimum canum and Ocimum sanctum, and leaf chloroform extract of Rhinacanthus nasutus against the larvae of An.subpictus (LC50 58.25, 88.15, 21.67, and 40.46 mg/L; LC90 298.31, 528.70, 98.34, and 267.20 mg/L) and peel methanol extract of Citrus sinensis, leaf methanol extract of Ocimum canum, and ethyl acetate extracts of Ocimum sanctum and Rhinacanthus nasutus against the larvae of Cx. tritaeniorhynchus (LC50 38.15, 72.40, 109.12, and 39.32 mg/L; LC90 184.67, 268.93, 646.62, and 176.39 mg/L), respectively. The efficacy shown by Schinustere binthifolia for knock down time and 100% mortality after 24 hours to adult mosquitoes from wild resistant population warrants further investigation of these compounds for IRS small scale whether singly or in blends. This essential oil may be of great value in complementing other compounds which are losing efficacy[25]. Kamaraj et al[26] reported that the highest larval mortality was found in leaf petroleum ether, flower methanol extracts of Cryptocoryne auriculata, flower methanol extracts of Leucas aspera and Rhinacanthus nasutus, leaf and seed methanol extracts of Solanum torvum, and leaf hexane extract of Vitex negundo against the larvae of An. subpictus (LC50 44.21, 44.69, 53.16, 41.07, 35.32, 28.90, and 44.40 mg/L; LC90 187.31, 188.29, 233.18, 142.66, 151.60, 121.05, and 192.11 mg/L, respectively) and against the larvae of Cx. tritaeniorhynchus (LC50 69.83, 51.29, 81.24, 71.79, 44.42, 84.47, and 65.35 mg/L; LC90 335.26, 245.63, 300.45, 361.83, 185.09, 351.41, and 302.42 mg/L, respectively).The highest repellency was observed in Zingiber officinale, a higher concentration of 5.0 mg/cm2 provided 100% protection up to 150 and 180 min against Cx. tritaeniorhynchus and An. subpictus, respectively[27]. Wandscheer et al[28] reported the naturally occurring insecticides may play a more prominent role in mosquito control programs in the future. Earlier, Georges et al[29] reported that the n-hexane, ethyl acetate, and methanol extracts of Cassia nigricans showed 100% larval mortality against Ochlerotatus triseriatus. This is because larval habitat treatment is more localized in time and space resulting in effective control. In tropical countries, plants are known to possess larvicidal, ovicidal and adulticidal activities[30]. Since there is no previous record of literature available about the mosquitocidal activity of the selected chemical compounds of P. cablin these present investigations serve as first hand information. The finding of the present investigation revealed that the chemical compounds of P. cablin possessed remarkable repellent and pupicidal activity against selected vector mosquitoes.
Acknowledgments
The authors are thankful to Higher Authorities for the grant of financial assistance with the Award of University Research Fellowship (Ref. No. No.H5/2009-2010/ URF Order of the Vice chancellore, 23011/2009) and also Professor and Head, Department of Zoology, Annamalai University for the laboratoryfacilities provided.
Comments
Background
Mosquitoes are well known for their public health importance since they cause major health problems and diseases. Indiscriminate use of several mosquitocidal agents caused various side effects. Thus there is a need to develop an alternative strategies to control vector mosquitoes. One such strategy is utilizing the plant and their secondary metabolites. In india, nearly 8000 plant species have been reported so far towards their insecticidal properties. In these, context, the present study was aimed to investigate the mosquitocidal activity of Pogostemon cablin essential oil against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes.
Research frontiers
The data obtained from the present experiments are in close agreement with the earlier reports of Saravanan et al (2007), Bagavan et al (2008) and Eliningala et al., (2011).
Related reports
In this present investigation, they have followed standard protocols to assess the mosquitocidal actions of selected plant essential oil. Their results showed that, The percent adult emergence was inversely proportional to the concentration of compounds and directly proportional to the pupal mortality. Among the five different compounds tested for pupicidal activity against selected vector mosquitoes, the patchouli alcohol was found to be most effective for pupicidal activity provided 28.44, 26.28 and 25.36 against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, respectively. These findings are in close with the earlier findings of Saravanan et al (2007), Bagavan et al (2008) and Eliningala et al., (2011).
Innovations & breakthroughs
Since, there is no previous record of literature available about the mosquitocidal activity of the selected plant essential oil and its components, the present report serve as first hand information on repellent and pupicidal activities against the adult and pupae of the selected vector mosquitoes.
Applications
Plants are always considered as vast repository of natural compounds, the exploration of research leading to their possible utilization certainly pave the way for search of new phytochemical compounds and their proper role in the near future as eco-friendly natural pesticides. These plant secondary metabolites can be used in nature as they are easily biodegradable, and safer to human beings.
Peer review
The present line of research quoted in this research article will surely focusing an insight in phytochemical research and their possible role towards the control of mosquitoes in any form, for example larval, pupal, egg or adult stages. Thus this plant essential oil and its compounds can be an alternative agent in Integrated Vector Control Programme (IVCP).
Footnotes
Foundation Project: Supported by Higher Authorities for the grant of financial assistance with the Award of University Research Fellowshi (Ref. No. No.H5/2009-2010/ URF Order of the Vice chancellore, 23011/2009.
Conflict of interest statement: We declare that we have no conflict of interest.
References
- 1.World Health Organisation, Malaria. 2010 http://www.who.int/mediacentre/factsheets/fs094/en/ WHO, Geneva. [Google Scholar]
- 2.Kamaraj C, Bagavan A, Rahuman AA, Zahir AA, Elango G, Pandiyan G. Larvicidal potential of medicinal plant extracts against Anopheles subpictus Grassiand Culex tritaeniorhynchus Giles (Diptera: Culicidae) Parasitol Res. 2009;104(5):163–1171. doi: 10.1007/s00436-008-1306-8. [DOI] [PubMed] [Google Scholar]
- 3.Klempner MS, Unnash TR, Hu LT. Taking a bite out of vector-trantmitted infectious diseases. N Engl J Med. 2007;356:2567–2569. doi: 10.1056/NEJMp078081. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Thomas TG, Rao S, Lal S. Mosquito larvicidal properties of an indigenous plant, Ipomoea cairica, Linn. Jpn J Infect Dis. 2004;57:176–177. [PubMed] [Google Scholar]
- 5.Govindarajan M, Mathivanan T, Elumalai K, Krishnappa K, Anandan A. Ovicidal and repellent activities of botanical extracts against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera: Culicidae) Asian Pac J Trop Biomed. 2011a;1:43–48. doi: 10.1016/S2221-1691(11)60066-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Govindarajan M, Mathivanan T, Elumalai K, Krishnappa K, Anandan A. Mosquito larvicidal, ovicidal, and repellent properties of botanical extracts against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae) Parasitol Res. 2011b;109(2):353–367. doi: 10.1007/s00436-011-2263-1. [DOI] [PubMed] [Google Scholar]
- 7.Mathew N, Anitha MG, Bala TSL, Sivakumar SM, Narmadha R, Kalyanasundaram M. Larvicidal activity of Saraca indica, Nyctanthes arbor-tristisand Clitoria ternatea extracts against three mosquito vector species. Parasitol Res. 2009;104(5):1017–1025. doi: 10.1007/s00436-008-1284-x. [DOI] [PubMed] [Google Scholar]
- 8.Rawani A, Ghosh A, Chandra G. Mosquito larvicidal activities of Solanum nigrum L. leaf extract against Culex quinquefasciatus Say. Parasitol Res. 2010;107(5):1235–1240. doi: 10.1007/s00436-010-1993-9. [DOI] [PubMed] [Google Scholar]
- 9.Pavela R, Vrchotova N, Triska J. Mosquitocidal activities of thyme oils (Thymus vulgaris L.) against Culex quinquefasciatus (Diptera: Culicidae) Parasitol Res. 2009;105(5):1365–1370. doi: 10.1007/s00436-009-1571-1. [DOI] [PubMed] [Google Scholar]
- 10.Koliopoulos G, Pitarokili D, Kioulos E, Michaelakis A, Tzakou O. Chemical composition and larvicidal evaluation of Mentha, Salvia, and Melissa essential oils against the West Nile virus mosquito Culex pipiens. Parasitol Res. 2010;107(2):327–335. doi: 10.1007/s00436-010-1865-3. [DOI] [PubMed] [Google Scholar]
- 11.Evergetis E, Michaelakis A, Kioulos E, Koliopoulos G, Haroutounian SA. Chemical composition and larvicidal activity of essential oils from six Apiaceae family taxa against the West Nile virus vector Culex pipiens. Parasitol Res. 2009;105(1):117–124. doi: 10.1007/s00436-009-1370-8. [DOI] [PubMed] [Google Scholar]
- 12.Matasyoh JC, Dittrich B, Schueffler A, Laatsch H. Larvicidal activity of metabolites from the endophytic Podospora sp. against the malaria vector Anopheles gambiae. Parasitol Res. 2011;108(3):561–566. doi: 10.1007/s00436-010-2098-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Isman MB. Botanical insecticides, deterrents and repellents in modern agriculture and an increasingly regulated world. Ann Rev Entomol. 2006;3:51–45. doi: 10.1146/annurev.ento.51.110104.151146. [DOI] [PubMed] [Google Scholar]
- 14.Worku M, Franco RA, Miller JE. Evaluation of the activity of plant extracts in Boer goats. Am J Anim Vet Sci. 2009;4:4–72. [Google Scholar]
- 15.Wu J, Lu X, Tang W, Kong H, Zhou S, Xu G. Application of comprehensive two dimensional gas chromatography-time-of-flight mass spectrometry in the analysis of volatile oil of traditional Chinese medicines. J Chromato A. 2004;1034:199–205. doi: 10.1016/j.chroma.2004.02.028. [DOI] [PubMed] [Google Scholar]
- 16.Deguerry F, Pastore L, Wu S, Clark A, Chappell J, Schalk M. The diverse sesquiterpene profile of patchouli, Pogostemon cablin, is correlated with limited number of sesquiterpene synthases. Arch Biochm Bioph. 2006;454:123–126. doi: 10.1016/j.abb.2006.08.006. [DOI] [PubMed] [Google Scholar]
- 17.WHO . Geneva: WHO; 1996. Report of the WHO informal consultation on the evaluation and testing of insecticides CTD/WHO PES/IC/96.1; p. 69. [Google Scholar]
- 18.Abbott WS. A method of computing the effectiveness of an insecticide. J Econ Entomol. 1925;18:265–267. [Google Scholar]
- 19.Eliningaya J, Kweka L, MrambaNyindo, Franklin Mosha, Ary G, Silva Insecticidal activity of the essential oil from fruits and seeds of Schinustere binthifolia Raddi against African malaria vectors. Parasites and Vectors. 2011;4:129. doi: 10.1186/1756-3305-4-129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Saravanan KS, Periyanayagam K, Ismail M. Mosquito larvicidal properties of various extract of leaves and fixed oil from the seeds of Caesalpinia bonduc (L) Roxb. J Commun Dis. 2007;39(3):153–157. [PubMed] [Google Scholar]
- 21.Mathivanan T, Govindarajana M, Elumalai K, Krishnappa K, Ananthan A. Mosquito larvicidal and phytochemical properties of Ervatamia coronaria Stapf. (Family: Apocynaceae) J Vector Borne Dis. 2010;47:178–180. [PubMed] [Google Scholar]
- 22.Mohan L, Sharma P, Srivastava CN. Comparative efficacy of Solanum xanthocarpum extracts alone and in combination with a synthetic pyrethroid, cypermethrin, against malaria vector, Anopheles stephensi. South Asian J Trop Med Pub Health. 2007;38(2):256–260. [PubMed] [Google Scholar]
- 23.Govindarajan M, Karuppannan P. Mosquito larvicidal and ovicidal properties of Eclipta alba (L.) Hassk (Asteraceae) against chikungunya vector, Aedes aegypti (Linn.) (Diptera: Culicidae) Asian PacJ Trop Med. 2011:24–28. doi: 10.1016/S1995-7645(11)60026-6. [DOI] [PubMed] [Google Scholar]
- 24.Bagavan A, Kamaraj C, Abdul Rahuman A, Elango G, Abduz Zahir A, Pandiyan G. Evaluation of larvicidal and nymphicidal potential of plant extracts against Anopheles subpictus Grassi, Culex tritaeniorhynchus Giles and Aphis gossypii Glover. Parasitol Res. 2008;104(5):1109–1117. doi: 10.1007/s00436-008-1295-7. [DOI] [PubMed] [Google Scholar]
- 25.Tren R, Roberts D. DDT and malaria prevention. Environ Health Perspect. 2010;118:14–15. doi: 10.1289/ehp.0901276. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Kamaraj C, Bagavan A, Rahuman AA, Zahir AA, Elango G, Pandiyan G. Larvicidal potential of medicinal plant extracts against Anopheles subpictus Grassi and Culex tritaeniorhynchus Giles (Diptera: Culicidae) Parasitol Res. 2008;104(5):1163–1171. doi: 10.1007/s00436-008-1306-8. [DOI] [PubMed] [Google Scholar]
- 27.Govindarajan M. Larvicidal and repellent properties of some essential oils against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi (Diptera: Culicidae) Asian Pac J Trop Med. 2011;4(2):106–111. doi: 10.1016/S1995-7645(11)60047-3. [DOI] [PubMed] [Google Scholar]
- 28.Wandscheer CB, Duque JE, da Silva MAN, Fukuyama Y, Wohlke JL, Adelmann J, Fontana JD. Larvicidal action of ethanolic extracts from fruit endocarps of Melia azedarach and Azadirachta indica against the dengue mosquito Aedes aegypti. Toxicon. 2004;44:829–835. doi: 10.1016/j.toxicon.2004.07.009. [DOI] [PubMed] [Google Scholar]
- 29.Georges K, Jayaprakasam B, Dalavoy SS, Nair MG. Pest managing activities of plant extracts and anthraquinones from Cassia nigricans from Burkina Faso. Bioresour Technol. 2008;99(6):2037–2045. doi: 10.1016/j.biortech.2007.02.049. [DOI] [PubMed] [Google Scholar]
- 30.Trudel RE, Bomblies A. Larvicidal effects of Chinaberry (Melia azederach) powder on Anopheles arabiensis in Ethiopia. Parasit Vectors. 2011;4:72. doi: 10.1186/1756-3305-4-72. [DOI] [PMC free article] [PubMed] [Google Scholar]