Larvicidal Efficacy of Cola gigantea, Malacantha alnifolia and Croton zambesicus Extracts as Phytoinsecticides Against Malaria Vector Anopheles stephensi (Diptera: culicidae)  

A. R. Jose1 , J. M. Adesina2
1. Department of Science Laboratory Technology, Rufus Giwa Polytechnic, P. M. B. 1019, Owo, Ondo State, Nigeria
2. Department of Crop, Soil and Pest Management Technology, Rufus Giwa Polytechnic, P. M. B. 1019, Owo, Ondo State, Nigeria
Author    Correspondence author
Journal of Mosquito Research, 2015, Vol. 5, No. 5   doi: 10.5376/jmr.2015.05.0005
Received: 02 Feb., 2015    Accepted: 18 Apr., 2015    Published: 05 May, 2015
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This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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Jose and Adesina, 2015, Larvicidal Efficacy of Cola gigantea, Malacantha alnifolia and Croton zambesicus Extracts as Phytoinsecticides Against Malaria Vector Anopheles stephensi (Diptera: culicidae), Journal of Mosquito Research, Vol.5, No.5 1-5 (doi: 10.5376/jmr.2015.05.0005)

Abstract

Malaria is transmitted by Anopheles stephensi and in controlling the malaria parasite Plasmodium spp., the vector mosquito has to be controlled. Extensive use of synthetic insecticides has resulted in environmental hazards and also in development of physiological resistance among vector mosquito species. Plant products are considered to be a potential alternative approach as they are environmentally safe, target specific and biodegradable. The n-hexane extracts of three plants viz., leaves of Cola gigantea, Malacantha alnifolia and Croton zambesicus were evaluated against mosquito third instar larvae under ambient laboratory condition at Environmental Biology Laboratory, Department of Science Laboratory Technology, Rufus Giwa Polytechnic, Owo, Ondo State, Nigeria. The larvicidal effects of the three plant species were tested at the following dosages: 0ml; 2ml; 4ml and 5ml. Larval mortality toxicity was calculated after 24 hours exposure period and the results obtained show that all the extracts exerted varying significant (P<0.05) percentages of larvae mortality effect; extract of C. gigantea was found to have the highest mortality rate at LC50 and LC90. From the phytochemical screening conducted on the plants, it was observed that the plants contain some secondary metabolites which are likely responsible for the larvicidal properties exhibited by the tested plants. The plants extracts show to be promising alternative to synthetic insecticides in malaria vector control programme and its adoption is advocated. Further studies need to be conducted to isolate and characterize the active molecules present in the plants.

Keywords
Malaria vector; Larvicidal; Phytochemical; Secondary metabolites; Toxicity

Mosquitoes represent a significant threat to human health because of their ability to vector pathogens that cause diseases that afflict millions of people worldwide (WHO, 2010)and they have attained the greatest public notoriety than any other arthropod (Lane and Crosskey, 1993); by transmitting over nine dreadful human diseases in over 100 countries causing mortality of nearly two million people annually (Klempner et al., 2007). In addition, mosquito bites can cause severe skin irritation through an allergic reaction to the mosquitos’ saliva causing bump and itching (Abdullah et al., 2003).
Mosquito control therefore, continues to be an important strategy in preventing mosquito borne diseases (Midega et al., 2010); control of mosquitoes during their developmental stages in aquatic medium seem to be the most appropriate period for control. Currently, application of synthetic insecticides remains the mostly widely used vector control method and its application not only targets the organism or population but non-target species are affected. Over-injudicious use of these synthetic insecticides has resulted in environmental hazards through persistence and accumulation of non-biodegradable toxic components in the ecosystem, development of insecticides resistance among mosquito species, bio magnification in the food chain and toxic effects on human health (Bansa et al., 2011; Devine and Furlong, 2007).
Globally, there has been a conscientious effort by scientists to overcome these problems and great emphasis has been placed recently on green chemistry for mosquito control, using natural plant products as they serve as a rich source for novel natural substances possessing insecticidal properties which are safe to human and ecosystem (Raveen et al 2014). During the last decade, various studies on natural plant products against vector mosquito indicate them as effective insecticides and larvicides for controlling different species of mosquitoes; thus serve as possible alternatives to chemical and synthetic insecticides for mosquito control (Arivoli and Samuel, 2011; Arivoli et al 2012; Arivoli and Samuel, 2012; Raveen et al 2012; Samuel et al 2012). In view of an increasing interest in developing insecticides of plant origin as alternative to chemical insecticides, this research work is to determine the larvicidal efficacy ofMalacantha alnifolia, Cola gigantea and Croton zambesicus extracts against malaria vector, Anopheles stephensi under laboratory condition.
1 Results and Discussion
1.1 Phytochemical screening of M. alnifolia, C. zambesicus and C gigantea leaves
Table 1 shows the phytochemical screening of the three (3) plant samples. The results showed that Tannin and Saponin were present in both M. alnifolia and C. zambesicus. All the plants evaluated showed the presence of glycosides, while Phlobatanninwas present in both M. alnifolia and C. gigantea. Flavonoid and Alkaloid were present in all the three plants evaluated.Plants are rich source of bioactive chemical compounds with insecticidal properties. The activity of crude plant extracts is often attributed to the complex mixture of active compounds (Sukhthankar, 2014). The larvicidal efficacy of evaluated plant extracts is dependent on the effect of one of these secondary metabolites present in them or the combined effort of one or more of the secondary metabolites. The environment is known to potentially influence the morphology and expression of compounds in plant (Senthilnathan et al., 2008). Environmental factors may be responsible to the variation in the secondary metabolites present in the chosen plant samples.


Table 1 Phytochemical screening of C. gigantea, M. alnifolia and C. zambesicus


1.2
Larvae mortality effect of M. alnifolia, C. zambesicus and C. gigantea extracts
Percentage mortality of mosquito larvae against hexane extract of the samples was presented in Figure 1. From the result obtained, it was observed that larvae mortality was concentration/dosage dependent, because as concentration of the plants extract increased larvae mortality increases.


Figure 1 Percentage mortality of mosquito larvae against hexane extracts of C gigantean, M. alnifolia and C. zambisicus


Twenty four hours after treatment, M. alnifolia treated dish recorded 100% larvae mortality followed by 91% mortality observed from C. zambisicus and 82% from C. gigantea. It was equally observed that apart from the least concentration (2ml), where C. gigantea had the highest effect on the mosquito larvae (31%), M. alnifolia proved to be more potent at higher concentration than the remaining two plant extracts as shown on the chart. Statistically, there existed significant differences (P<0.05) in larvae mortality among the various plant extracts.
The percentage mortality effects of the three (3) plant samples (C. gigantea, C. zambesicus and M. alnifolia) revealed the insecticidal properties of these plant species, which are comparable to well established insecticidal plant species. Mohan, et al., (2007) studied larvicidal activities of 51 Brazilian medicinal plants against Aedes aegyti and estimated the LC50 and LC90 against 3rd instar larvae of C. quinquefasciatus that were 183 and 408 ppm respectively. Minjas and Sarda (1986) reported variations in toxicological efficacy with three mosquito species to the crude aqueous extract of fruit pods of Swartzia madagascariensis to which C. quinquefasciatus was completely susceptible while A. gambiae was relatively more susceptible to the extract than A. aegypti. Similar observations were made by Sujatha et al (1988) with petroleum ether extract of six plants Acorus calamus, Ageratum conyzoides, Annona squamosa, Bambusa arundanasia, Madhuca longifolia and Citrus medica against three species of mosquitoes, An. gambiae, Ae. aegypti and Cx. quinquefasciatus. Pathak et al (2000) also reported variations in larvicidal efficacy of essential oil extracts from four plants Tagetes erecta, Ocimum sanctum, Mentha piperita and Murraya koenigii against three species of mosquitoes, An. stephensi, Ae. aegypti and Cx. quinquefasciatus. In a related development, Raghavendra et al. (2009) observed toxicity of hexane extract of the dried fruit of Solanum nigrum against five mosquito species of three genera: An. culicifacies sibling species A, Ae. aegypti, An. culicifacies sibling species C, Cx. quinquefasciatus and An. Stephensi and this was in tandem with the findings recorded from this study.
1.3 Lethal concentration effects of M. alnifolia, C. zambisicus and C. gigantea hexane extract on mosquito larvae
Table 2 shows the result of the lethal concentration of the three plant samples. The result shows that the plant samples have larvicidal activity in 24hours of exposure. The extracts of M. alnifolia displayed highest larvicidal activities with LC50 and LC90 at108.30ppm and 604.43ppm respectively at 10ml dosage rate, followed by C. gigantea LC50 and LC90. C. gigantea have least mortality rate at LC50 and LC90 at 2ml dosage rate. All the plant samples displayed larvicidal activity which is in conformity with the earlier works done on variations in larvicidal efficacy of the extracts in different mosquito species.


Table 2 Lethal concentration effects of M. alnifolia, C. zambisicus and C. gigantean hexane extract on mosquito larvae


Sosan et al. (2001) reported larvicidal activities of essential oils of Ocimum gratissium, Cymbopogon citrus and Ageratum conyzoides against Ae. aegypti and achieved 100% mortality at 120, 200 and 300 ppm concentrations respectively. Similarly, it was reported that the essential oil of Ipomoea cairica Linn. possesses remarkable larvicidal properties as it could produce 100% mortality in the larvae of Cx. tritaeniorhynchus, Ae aegypti, An. stephensi and Cx. quinquefasciatus mosquitoes at concentrations ranging from 100 to 170 ppm (Thomas et al., 2004). Dwivedi and Kawasara (2003) found acetone extract of Lantana camara to be most effective against Cx. quinquefasciatus larvae at the dosage of 1 ml/100 ml. Latha et al. (1999) reported that Piper longum and Zingiber wightianum extracts at 80 mg/l caused complete mortality in Cx. quinquefasciatus and 60 mg/l for Cx. sitiens. In the present investigation LC90 values of methanol and ethanol extracts of roots of A. saccata, leaf of A. squamosa and fruits/pericarp of G. cochinchinensis against Ae. albopictus and Cx. Quinquefasciatus larvae ranged between 31.80 and 155ppm. Studies with essential oil of Ocimum Americans and O. gratissium showed LC50 at 67 and 60 ppm respectively against Ae. aegypti larvae (Cavalcanti et al., 2004).
Findings indicate that the evaluated plants possess insecticidal properties that could be employed as phytoinsecticide which apart from serving as an alternative to synthetic insecticides in mosquito infestation control, it is more environmentally friendly, safe, and will not pose any threat to non-target organisms. Further investigations are needed to confirm the plants insecticidal activity against all stages of development in a wide range of mosquito species and also the mode of action responsible for larvicidal and adult emergence inhibition activity of A. stephensis and other species of mosquito.
2 Materials and Methods
The study was conducted in the Biology Laboratory, Department of Science Laboratory Technology, Rufus Giwa Polytechnic, Owo, Ondo State, Nigeria (Latitude 7° 11ʼ N and Longitude 5° 35ʼ E) under ambient laboratory condition.
2.1 Plant collection and Extract preparation
The studied plant leaves (Croton zambescis, Cola gigantea and Malancatha alnifolia) were all collected from Ute in Ose Local Government Area of Ondo State, Nigeria (Latitude 7° 11ʼ N and Longitude 5° 35ʼ E) and were identified at Department of Forestry and Wood Technology, Rufus Giwa Polytechnic, Owo, Ondo State, Nigeria, where specimen voucher was deposited. The collected plant materials (C. zambesicus, C. gigantea and M. alnifolia) were washed in clean water to remove dirt and shade dried for 2 weeks before milled into powder using an electric blender.
The extracts of the three plants were obtained using solvent n-hexane. A total of 500g of the dried powdered leaves samples were subjected to extraction using n-hexane for a period of 8 hours to obtain the crude extracts using Soxhlet apparatus. The n-hexane extracts obtained were kept in a cool dry place until testing for bioassay.
The test organism’s, i.e. first instar larvae of Anopheles. stephensi were collected from stagnant water within the student hostel, Rufus Giwa Polytechnic Owo, Ondo State, Nigeria and kept in a plastic container containing dechlorinated tap water; feed with powdered yeast and dog biscuits till testing for bioassays (Pugazhvendan and Elumali, 2013). A. stephensi was authenticated upon adult emergence from the culture maintained. In the larvicidal assay, third and fourth instars larvae of A. stephensi were exposed to test concentration 2, 4, 8 and 10ml of hexane extracts from leaves of Malnifolia, C. zambesicus and C. gigantea in 100ml of distilled water. The plant extracts were added to the distilled water in the beakers. A control was also maintained by not adding any known concentration of the plant extract to the distilled water in the beaker. Ten (10) larvae per concentration were used for all the larvae experiment. All the experiments were carried out at 20 ± 2°C and 75 ± 5 % relative humidity under 12:12 hour light and dark cycles (Kamaraj et al 2011).
Each concentration of the plant extracts had 3 replicates and were arranged in Complete Randomised Design (CRD). The number of dead larvae was recorded 24 hours after treatment. The percentage mortality value was calculated.
Percentage mortality = 
 

2.2
Phytochemical Screening Methods
Simple standard chemical tests were carried out for phytochemical screening and such tests were used to detect the presence of bioactive agents such as alkaloids, tannins, phlobatanin, cardiac glycosides, saponins, and flavonoids as described by Sofowora (1993), Trease and Evans (1998); Heyde et al., (1984); Prashant et al., (2011).
2.3 Statistical Analysis
Data from effect of concentration and mortality were subjected to Analysis of Variance (ANOVA). Prior to analysis the percentage data obtained was arcsine transformed. LC50 and LC90 were determined using profit analysis (Finney, 1971). Result with P<0.05 were considered to be statistically significant.

Acknowledgement
The authors acknowledge Osaghale Marcus, Department of Science Laboratory, Rufus Giwa Polytechnic, Owo, Ondo State, Nigeria for his support during the study.
References
Abdullahi K., Muhammad S., Manga S.B., and Tunau I.M., 2003, Chloroquine resistance Plasmodium falciparum in Sokoto North-West Nigeria. African Journal of Biotechnology, 2(8): 244-245
http://dx.doi.org/10.5897/AJB2003.000-1050
Arivoli S., and Samuel T., 2011, Mosquitocidal activity of Hyptis suaveolens (L.) Poit (Lamiaceae) extracts against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus (Diptera: Culicidae). International Journal of Recent Scientific Research, 2(5):143-149
Arivoli S., and Samuel T., 2012, Larvicidal efficacy of Strychnos nuxvomica Linn. (Loganiaceae) leaf extracts against the filarial vector Culex quinquefascaitus Say (Diptera: Culicidae). World Journal of Zoology, 7(1):06-11
Arivoli S., Ravindran K.J., Raveen R., and Samuel T., 2012, Larvicidal activity of botanicals against the filarial vector Culex quinquefasciatus Say (Diptera: Culicidae). International Journal of Research in Zoology, 2(1):13-17
Cavalcanti E. S.B., Morais S.M., Lima M.A.A., and Santana E.W.P., 2004, Larvicidal activity of essential oils from Brazilian plants against Aedes aegypti L. Memórias do Instituto Oswaldo Cruz, 99(5): 541-544
http://dx.doi.org/10.1590/S0074-02762004000500015
Devine G.J., and Furlong M.J. 2007, Insecticide use: Contexts and ecological successions. Agriculture and Human Values,24: 281-306
http://dx.doi.org/10.1007/s10460-007-9067-z
Dwivedi SC, and Karwasara K., 2003, Larvicidal activity of five plants extracts against Culex quinquefasciatus. Indian Journal Entomology, 65(3): 335-338
Finney D.J., 1971, Probit analysis, 3rd edition. Cambridge, England: Cambridge University Press
Heyde J.V.D., Saxena R.C., and Schmutterer H., 1984, Neem oil and neem extracts as potential insecticide for control of Hemipterous rice pests. Proceedings of the 2nd International Neem Conference, Rauischholzhausen, Germany, pp. 337-390
Kamaraj C., Bagavan A., Elango G., Abduz A., Rajakumar G., Marimuthu S., Santhoshkumar T., and Abdul Rahuman A., 2011, Larvicidal activity of medicinal plant extracts against Anopheles subpictus and Culex tritaeniorhynchus. Indian Journal of Medical Research, 134: 101-106
Klempner MS, Unash TR, and Hu LT., 2007, Taking a bite out of vector transmitted infectious diseases. New English journal of medicine, 356:2567-2569
http://dx.doi.org/10.1056/NEJMp078081
Lane R.P., and Crosskey R.W. 1993, Medical insects ad arachnids: Chapman and Hall London, pp. 120-214
Latha C., Vijhayakumar P.D., Velayudhan S., and Joseph A., 1999, Biological activity of indigenous plant extracts as mosquito larvicides. Indian Journal          Experimental Biology, 37: 206-8
Midega J.T., Muturi E.J., Baliraine F.N., Mbogo C.M., Githure J., and Beier J.C., 2010. Population structure of Anopheles gambiae along the Kenyan coast. Acta Tropics,114: 103-108
http://dx.doi.org/10.1016/j.actatropica.2010.01.011
Minjas J.N., and Sarda R.K., 1986, Laboratory observations on the toxicity of Swartzia madagascariens (Leguminaceae) extract of mosquito larvae. Transitional Research Society of Tropical Medicinal Hygiene, 80: 460-461
http://dx.doi.org/10.1016/0035-9203(86)90345-7
Mohan L., Sharma P., and Srivastava C.N., 2007, Evaluation of Solanum xanthocarpum extracts as mosquito larvicides. Journal of Environmental Biology, 26(2): 399-401
Pathak N., Mittal PK., Singh OP., Sagar V., and Vasudevan P., 2000, Larvicidal action of essential oils from plants against the vector mosquitoes Anopheles stephensi (Liston), Culex quinquefactiatus (Say) and Aedes aegypti (L). International Pest Control, 42: 53-55
Prashant T., Bimlesh K., Mandeep K., Gurpreet K., and Harleen K., 2011, Phytochemical screening and extraction: A Review. Internationale Pharmaceutica Sciencia, 1(1): 23-28
Pugazhvendan SR., and Elumali K., 2013, Larvicidal activity of selected plant essential oil against important vector mosquitoes: Dengue vector, Aedes aegypti (L.), Malaria vector, Anopheles stephensi (Liston) and Filarial vector, Culex quinquefactiatus (Say) (Diptera: Culicidae). Middle-East Journal of Scientific Research, 18(1): 91-95 Raghavendra K., Singh SP., Subbarao SK., & Dash AP., 2009 Laboratory studies on mosquito larvicidal efficacy of aqueous and hexane extracts of dried fruit of Solanum nigrum Linn. Indian Journal of Medical Research, 130:74-77
Raveen R., Dhayanidhi P., Dhinamala K., Arivoli S., and Samuel T., 2012, Larvicidal activity of Pedilanthus tithymaloides (L.) Poit (Euphorbiaceae) leaf against the dengue vector Aedes aegypti (L.) (Diptera: Culicidae). International Journal of Environmental Biology, 2(2):36-40
Raveen R., Kamakshi K.T., Deepa M., Arivoli M., and Samuel Tennyson, 2014, Larvicidal activity of Nerium oleander L. (Apocynaceae) flower extracts against Culex quinquefasciatus Say (Diptera: Culicidae). International Journal of Mosquito Research, 1 (1): 38-42
Samuel T., Ravindran KJ., and Arivoli S., 2012, Screening of twenty five plant extracts for larvicidal activity against Culex quinquefasciatus Say (Diptera: Culicidae). Asian Pacific Journal of Tropical Biomedicine, 2: S1130-S1134
http://dx.doi.org/10.1016/S2221-1691(12)60372-4
Senthilnathan S., Choi M.Y., Seo H.Y., Paik C.H., Kalaivani K., and Kim J.D., 2008, Effect of azadirachtin on acetylcholinesterase (AChE) activity and histology of the brown plant hopper Nilaparvata lugens (Stål). Ecotoxicology and Environmental Safety, 70: 244-50
http://dx.doi.org/10.1016/j.ecoenv.2007.07.005
Sofowora, A., 1993, Medicinal Plants and Traditional Medicine in Africa, 3rd ed., pp. 195-238
Sosan M.B., Adewoyin F.B., Adewunmi C.O., 2001, Larvicidal properties of three indigenous plant oils on the mosquito Aedes aegypti. Nigerian Journal of Natural Production Medicine 5: 30-33
http://dx.doi.org/10.4314/njnpm.v5i1.11719
Sujatha CH., Vasuki V., Mariappan T., Kalyanasundaram M., Das T., 1988, Evaluation of plant extracts for biological activity against mosquitoes. International Pest Control, 30:122-124
Sukhthankar JH., Kumar H., Godinho MHS., and Kumar A., 2014, Larvicidal activity of methanolic leaf extracts of plant, Chromolaena odorata L. (Asteraceae) against vector mosquitoes. International Journal of Mosquito Research, 1 (3): 33-38
Thomas T.G., Rao S., and Lal S., 2004, Mosquito larvicidal properties of an indigenous plant, Ipomoea cairica Linn. Japanese Journal of Infectious Diseases,57(16): 176-178
Trease G.E., and Evans W.C., 1998, Pharmacognosy. Macmillan publishers, Brailliar Tiridel, Canada

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