Larvicidal Research Articles

Lecanicillium psalliotae (Hypocreales: Cordycipitaceae) Exerts Ovicidal and Larvicidal Effects against the Sheep Blood-Feeding Nematode Haemonchus contortus through Its Liquid Culture Filtrates.

Nematophagous fungi (NF) form part of the soil microbiota and are natural enemies of nematodes, helping to regulate nematode populations. A verticillate NF isolated from soil from Tepalcingo, Mexico, was morphologically and molecularly characterised. This fungus was cultured in two different liquid media-Czapek-Dox broth (CzDoxB) and sweet potato dextrose broth (SPDB)-for 21 days. The ovicidal (OA) and larvicidal (LA) activities of fungal liquid culture filtrates (LCFs) were assessed in 96-well microtitre plates at different concentrations against Haemonchus contortus after 48 h. The morphological and molecular identification revealed the presence of Lecanicillium psalliotae. Additionally, the groups of compounds associated with nematocidal activity were determined from a qualitative chemical profile (QCP) using different reagents. The highest OA of the LCFs was obtained at 25 mg/mL from SPDB and CzDoxB and amounted to 97.2 and 99.06%, respectively. Meanwhile, the highest LA recorded with these LCFs at 100 mg/mL was 54.27% and 96.8%, respectively. The QCP revealed the presence of alkaloids and tannins in both LCFs that have previously been associated with nematocidal activity. Lecanicillium psalliotae exerted an important effect on H. contortus and could be of significance in future studies focused on the control and prevention of haemonchosis in small ruminants.

Atividades biológicas de Agave sisalana com ênfase para a ação antimicrobiana: uma revisão da literatura

Objetivo: Relatar as principais atividades biológicas de Agave sisalana, descrevendo detalhes de sua classificação botânica, aspectos da composição química e bioativa, além de destacar seu uso como antimicrobiano. Metodologia: Trata-se de uma revisão da literatura de caráter descritiva com abordagem qualitativa, elaborada por meio da análise de materiais indexados nas plataformas: SciELO, PubMed e o portal de periódicos da CAPES, publicados entre os anos de 2002 a 2021, redigidos nos idiomas: português, inglês e espanhol. Após aplicação dos critérios de inclusão e exclusão, bem como leitura dos materiais, 38 conteúdos foram selecionados para a composição do presente estudo. Resultados e discussão: A atividade bioativa de Agave sisalana, está vinculada aos componentes do seu metabolismo secundário, onde podem ser mensurados: derivados alcaloides, cumarinas, taninos e saponínicos. No que se refere as saponinas do sisal, estas são apontadas como detentoras de ação antifúngica e antibacteriana, principalmente contra microrganismos patogênicos. Além das atribuições mencionadas, os estudos vêm mostrando seus efeitos como: inseticida, larvicida, ovicida, antiparasitário, antioxidante, imunomodulador, analgésico, anti-inflamatório, sob a atividade comportamental e neuroquímica, bem como na quimioprevenção e controle do câncer. Conclusão: Variadas são as aplicações da Agave sisalana, seja ao âmbito industrial, artesanal terapêutico ou na agropecuária. Sua atividade antimicrobiana é cientificamente comprovada, seja na inferência de fungos ou bactérias, fazendo desta uma importante alternativa, frente a incidência de microrganismos resistentes.

Comparative Studies on the Larvicidal Activity of Lantana camara Linn. (Wide Sage) and Tithonia diversifolia (Hemsl) A.Gray (Mexican Sunflower) Leaf Extract on Anopheles Mosquito Larvae

The larvicidal activity of Lantana camara and Tithonia diversfolia leaf extract against anopheles mosquito larvae was investigated in this study during October 2019 in the Centre for Disease Surveillance (Malaria Research Laboratory) University of Jos. Anopheles mosquito larvae was obtained from stagnant water pond behind Zoology Undergraduate Research Laboratory. Aqueous and methanolic extraction was carried out on the dried and pulverized leaves of both plants. Three different concentrations were used for the treatments which were 100mg/ml, 50mg/ml, and 25mg/ml. 48 containers(specimen bottles) were used with each containing 10 larvae. Each concentration had three replicates and a control also in triplicate. The treatments were observed for 24 hours after which it was observed that all the extracts were effective against the larvae and the difference being only in the lethal time. The mean mortality was highest for Tithonia diversifolia aqueous extract followed by Lantana camara aqueous extract, after which is Lantana camara methanolic extract and then Tithonia diversifolia aqueous extract. Mortality of Anopheles mosquito larvae exposed to the plant extracts increased with exposure and concentration of extracts. The higher the concentration, the higher the mortality rate of the larvae. Going by the above deductions, it can be rightly put that the effect of the extract is dose and time dependent as evidenced by increase in the percentage mortality with increase in concentration and time. The extracts from both plants contain bioactive compounds against larvae of anopheles mosquito and could be used in stagnant water bodies and drainages which are known to be breeding sites for mosquitoes and the leaves of both plants could be used in the production of mosquito repellants. The study also recommends that both plants be planted around residential areas to prevent breeding of anopheles mosquitoes.

Óleo essencial das cascas descartadas do fruto de Hymenaea courbaril L. como larvicida frente Aedes aegypti

Este estudo objetivou avaliar a atividade larvicida do óleo essencial (OE) extraído das cascas do fruto comumente descartadas de Hymenaea coubaril L. Para extração do OE foi utilizada a técnica de hidrodestilação em um sistema extrator de Clevenger modificado. Os constituintes químicos foram obtidos por Cromatografia Gasosa acoplada a espectrometria de massas (CG/EM). Para atividade larvicida submeteu-se larvas de Aedes aegypti a soluções do OE em concentrações de 10-100 mg L-1, onde avaliou-se a mortalidade das larvas e determinou-se a CL50. O β-ocimeno foi quantificado como majoritário no OE. Observou-se ação do OE como larvicida onde foi determinada a CL50 de 16,6 mg L-1. Os resultados obtidos permitiram concluir que o OE estudado apresentou atividade larvicida eficiente contra as larvas de Aedes aegypti, sendo importante e incentivado seu uso e aplicação.

Chemical composition and larvicidal activity of Citrus limonia Osbeck bark essential oil

Aedes aegypti mosquito arouses the interest of public authorities, as it is a vector for four diseases (dengue, zika, chikungunya, and yellow fever) and one of the ways to combat it is through insecticides. In this study, the main constituent, the predominant class of essential oil extracted from the husks of Citrus limonia Osbeck was identified and evaluated to know if it has biological activity against larvae in the third stage of Ae.aegypti. gas chromatography coupled with mass spectrometry (CG-MS); larvicidal activity as described by the World Health Organization (WHO) was evaluated and the lethal concentration (LC50) from the Probit model was calculated. The results show that the oil consists mainly of limonene, beta-Pinene, meta-Cymene, beta.-Phellandrene and alpha-Pinene, in which the predominant class was monoterpenes and the lethal concentration, CL50, was 67.18 µg.mL-1. Therefore, the oil has potential larvicidal activity. Key words: Volatile compounds, monoterpenes, aedes aegypti, limonene, natural insecticide.

2-Hydroxy-4-Methoxybenzaldehyde: Larvicidal Structure-Activity Studies

2-Hydroxy-4-methoxybenzaldehyde (1) , a compound isolated from Mondia whytei (Hook) Skeels (Asclepiaceae) roots exhibited larvicidal activity (LD 50 22 mg/mL). A total of 18 other derivatives and closely related congeners revealed varying levels of larvicidal activity. Several closely related congeners, like 2-benzyloxy-4-methoxybenzaldehyde (2) , 2-hydroxybenzaldehyde (12) , 2-benzyloxybenzaldehyde (3) and benzylphenyl ether (4) , showed marked improvement in activity (LD 50 10, 9, 4.8, 1.2 mg/mL, respectively) against Anopheles gambiae larvae. 2-Benzoyloxy-4-methoxybenzaldehyde (5) exhibited similar activity level (LD 50 28 mg/mL) as 1 . KEY WORDS : 2-Hydroxy-4-methoxybenzaldehyde, Larvicides, Structure-activity relationships, 2-Hdroxybenzaldehyde, 2-Benzyloxybenzaldehyde, Benzylphenyl ether Anopheles gambiae , Bull. Chem. Soc. Ethiop. 2005, 19(1), 61-68.

Investigations on the Larvicidal Effect of Red Algal Seaweeds of Rameswaram Coast Against Tobacco Caterpillar Spodoptera Litura (Fab.)

Investigations on the insecticidal activity of Red algal seaweeds viz., Gracilaria corticata J. Agardh, Liagora ceranoides J. V. Lamouroux, and Asparagopsis taxiformis (Delile) collected from Rameswaram coastal ecosystem against Leaf eating caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) was conducted in the Department of Entomology, Faculty of Agriculture, Annamalai University, India during 2016-2018. Powdered seaweeds at 1, 3, 5, 7, 10 and 20 per cent concentrations were investigated for their toxicity and insect growth regulator activity aganist S.litura under CRD in free choice test with three replications along with control. Observations showed that, larval mortality noticed after 36 hours after treatment in G. corticata treatments and even 100 per cent mortality was achieved at 72 hours of treatment, whereas the other two seaweeds exhibited larval mortality only after 72 hours of treatment and extended further to pupation and adult emergence. Among the concentrations the higher doses (20 and 10%) exhibited the maximum larval mortality (100%) while the maximum doses of other two seaweeds powder treatments did not, exhibited cent per cent larval mortality at any point of time and even pupated and gone for adult emergence also. The results displayed that, all the seaweed had exhibited larval mortality and their inhibiting substance inside needs to be investigated.

Corrigendum to "Larvicidal Potential of Five Selected Dragonfly Nymphs in Sri Lanka over Aedes aegypti (Linnaeus) Larvae under Laboratory Settings".

[This corrects the article DOI: 10.1155/2018/8759459.].

In-vitro study on the larvicidal activity of Manihot glaziovii peel extract against Aedes aegypti larvae

Use of chemical method to control Aedes aegypti population in the Dengue endemic areas caused the emergence of a resistant strain of this species to insecticide compounds, including temephos. Exploration of the alternative compounds that have larvicidal effects is needed, such as natural products derivate from plants. The current study was designed to evaluate the effective dosage of methanolic extract of Manihot glaziovii peel against the third instar larvae of Aedes aegypti. Bioassay test was performed based on the WHO procedure to occupy the 24 hours exposure of five levels dosages of Manihot glaziovii peel extract, namely 1,800, 2,400, 3,000, 3,600 and 4,200 ppm respectively. As many as 25 of healthy Aedes aegypti larvae were subjected into each group, five-time replicated and compared with tap water control group. The mortality rate of Aedes aegypti larvae has increased due to the increase in treatment groups dosages, ranged from 44–97.6%. It is significantly different in larvae mortality rate between different treatment groups. There was no observation of killed larvae in the control group. LD50 and LD90 of methanolic extract of Manihot glaziovii peel were measured 2,027 ppm and 3,772 ppm, respectively. This result suggests the possible use as an ecofriendly larvicide against Aedes aegypti larvae. Further investigation is needed to obtain secondary metabolites of this plant.

Insecticidal and larvicidal activities of cinamic acid esters isolated from Ocimum gratissimum L. and Vitallaria paradoxa leaves against Tribolium castaneum Hebst (Coleoptera:Tenebrionidae): Poster

Insecticidal and larvicidal activities of cinamic acid esters isolated from Ocimum gratissimum L. and Vitallaria paradoxa leaves against Tribolium castaneum Hebst (Coleoptera:Tenebrionidae): Poster

Test of Larvacide Activity from Some Sponge Extracts to Aedes aegypti Larvae

Marine organisms have been known produce certain compounds those could lead for medicine purposes. Sponges are one and the most studied for this aim. oneof the important biological activities which expected from sponge are larvacide activity. The aims this research was to test the larvacide activity aagainst Aedes aegypti larvae from some of sponge extract. Sponge samples were taken from Malalayang Waters, (N 01 ° 27'37 "E 124 ° 47'30") on November 2014 with the depth varies from 2-15 m with SCUBA. The extraction, preparation of the larvae and activity testing was performed on Biomolecular and Marine Pharmacy Laboratory Faculty Fisheries and Marine Science. The sponge samples were cutted and soaked in 95% Ethanol for over night with 3 repetitions to obtain ethanolic extracts. The extract were filtered and evaporated using freeze dryer then tested onto 10 instars 3 instars m larvae that had been previously maintained. the test was made in triplowith 24 hours observation. abate was used as positive control while negative control clean water was used.The test results showed that of 11 Sponge tested, 10 species showed larvacidal activity and marine sponge extract Tedania sp. has the highest activity compared to 9 extracts. As a suggestion of this research the further purification of Tedania sp. extract is needed to know the structure of active compound.Keywords: Aedes aegypti, Larvacide, Sponge extractABSTRAKOrganisme laut yang dapat dikembangkan menjadi bahan sediaan obat antara lain sponge, dan merupakan salah satu organisme laut yang banyak diteliti. Beberapa aktivitas biologis penting yang diharapkan dari ekstrak sponge salah satunya adalah aktivitas larvasida. Penelitian ini bertujuan untuk menguji aktivitas larvasida nyamuk Aedes aegypti dari beberapa ekstrak Sponge. Sampel sponge diambil di perairan Malalayang, tepatnya di koordinat N 01°27’37” E 124°47’30” pada bulan November 2014 di kedalaman 2-15 m. Sedangkan untuk tahap ekstraksi, penyiapan larva uji dan pengujian aktivitas larvasida di lakukan di laboratorium Biomolekular dan Farmasitika Laut program studi Ilmu Kelautan, FPIK UNSRAT. Dalam penelitian yang dilakukan, sampel diambil di perairan menggunakan peralatan SCUBA. Setelah itu diekstrak dengan larutan etanol 95% dan direndam selama 24 jam dan dilakukan 3 kali pengulagan untuk mendapatkan ekstrak etanolik. Sampel dikeringkan dengan menggunakan alat freeze dryer kemudian diujikan ke 10 ekor larva nyamuk fase instar 3 yang telah dipelihara sebelumnya. Pengujian dilakukan sebanyak 3 kali pengulangan dengan lama pengamatan 24 jam pengamatan. Sebagai kontrol positif digunakan bubuk abate yang biasa dijual di pasaran sedangkan kontrol negative atau tanpa perlakuan digunakan air bersih. Data hasil pengamatan diolah menggunakan Microsoft excel.Hasil pengujian menunjukkan bahwa Dari 11 Sponge yang diuji, 10 jenis menunjukan aktivitas larvasida dengan persentase mortalitas yang bervariasi dan ekstrak sponge laut Tedania sp. memiliki aktivitas tertinggi dibandingkan dengan 10 jenis ekstrak sponge lain dalam pengujian. Sebagai saran dalam penelitian ini yaitu Perlu dilakukan pemurnian lanjut ekstrak lebih lanjut dari ekstrak sponge Tedania sp. yaitu ke tahap partisi dan Perlu adanya variasi konsentrasi dalam pengujian.Kata Kunci : Aedes aegypti, Larvasida, ekstrak Spong

Comparative larvicidal efficacies of <i>Nymphae lotus</i> fractions against <i>Anopheles</i> mosquito larvae

No Abstract Keywords: Larvicidal, Nymphaea lotus , Anopheles , leaves extracts, fractions, Culicidae

Antiproliferative activity and phytochemical analysis of methanol leaf extract of Grewia nervosa

Grewia nervosa belonging to the Malvaceae family is abundantly found in the Western Ghats of India. Though G. nervosa is considered to have therapeutic potential, this has not been scientifically corroborated. However, the plant has been scientifically proven to demonstrate insecticidal, larvicidal and free radical scavenging activities.

Mosquito larvicidal trihydroxylindene derivative from submerged cultures of Trametes species

Larvicidal active pure chemical compound was isolated from a Trametes species using conventional chemistry techniques like solvent-solvent extraction and liquid-solid adsorption techniques. Larvicidal assays carried out on the purified compound, LC50 and LC90 values were calculated and found to be 23.5 and 67.4 ppm, respectively. The chemical structures of the purified compound was elucidated using standard spectroscopic techniques: 1D (1H; 13C) and 2D (HSQC, COSY, NOESY, HMBC; DEPT) NMR experiments, assignments. The results indicate the potential of novel compounds with mosquito larvicidal activity from the Trametes species commonly found in the Kenyan forest ecosystems. Key words: Mosquito larvicidal, Aedes aegypti, trihydroxylindene derivative, Trametes species.

Larvicidal activity of recombinant Escherichia coli expressing scorpion neurotoxin AaIT or B.t.i toxin Cyt2Ba against mosquito larvae and formulations for enhancing the effects

To assess the larvicidal effects of recombinant Escherichia coli expressing scorpion neurotoxin AaIT or Bacillus thuringiensis subsp israelensis (B.t.i) toxin Cyt2Ba against the second instar larvae of Culex pipiensquinquefasciatus and Aedes albopictus and compare different formulations for their larvicidal effects. The AaIT- or Cyt2Ba-coding sequences were cloned into pET28a(+) and the recombinant plasmids were transformed into E. coli BL21(DE3). After induction with IPTG, the recombinant proteins expressed by the recombinant E. coli were detected and identified by SDS-PAGE and Western blotting, respectively. The larvicidal activity of the bacterial suspension was tested at different concentrations against mosquitoes. The effective engineered bacteria were prepared into dry powder with different formulations, and their larvicidal activity was tested. AaIT and Cyt2Ba proteins were successfully expressed in E. coli. The recombinant AaIT protein showed no virulence to the mosquito larvae. The suspension of the recombinant E. coli expressing Cyt2Ba protein exhibited a stronger killing effect on Aedes albopictus larvae than on Culex pipiens quinquefasciatus larvae at 48 h (P<0.001) with LC50 of 3.00×106 cells/mL and 1.25×107 cells/mL, respectively. The dry powder of the engineered bacteria formulated with yeast extract, wheat flour or white pepper powder at the mass ratio of 1:1 showed the strongest killing effect on mosquito larvae (P=0.044), and the formulation with white pepper powder produced a stronger killing effect than formulations with yeast extract or wheat flour (P=0.002). The B.t.i Cyt2Ba protein expressed in E. coli BL21(DE3) shows a good larvicidal activity against mosquitoes, and appropriate formulations of the engineered bacteria can enhance its efficiency in mosquito control.

Evaluation of acaricidal efficacy of Synadenium glaucescens (Euphorbiaceae) against boophilus species

Synadenium glaucescens is a traditional medicinal plant used by some communities in Tanzania for the management of various diseases in animals and human including the use for control of ticks in cattle. The aim of this study was to investigate the ‘acaricidal effect’ of extracts from this plant on Boophilus decoloratus and B. microplus. The methodology involved the use of larval and adult immersion tests. Results indicated low larvicidal (corrected mortality 37.5%) and adulticidal (corrected mortality 33.33%, LC50 666.91) activities respectively for methanol and ethanol extracts from leaves. Other extracts of this plant showed a non-significant activity of mortality. Thus, it is not recommended for field trials, rather additional research is needed to determine its potentials especially using fresh plant material Key words: Synadenium glaucescens, Acaricidal activity, ticks, Tanzania.

Bioinformatical results based on statistical methods for endectocide products against fly-larvae.

The larvicide effects of three endecticide products were studied against house fly larvae. Repeated-measure design was used for the analysis of variance. The observed data followed different distributions. For this reason, instead of the repeated measure ANOVA, three fast statistical methods were applied simultaneously. First, the test for homogeneity was carried out for registered samples by using the Friedman test, and the Wilcoxon-Wilcox test was applied for pairwise comparisons. Secondly, an extended median test was applied for the same problem of test for homogeneity, and the Neményi test was used for pairwise comparisons. Thirdly, a 2 x 2 contingency table analysis was carried out, exploiting the specific feature of the database and informatical tools. The three simultaneous evaluations enabled us to come to sound, affirmative conclusions. In the course of veterinary-biological interpretation we demonstrated the statistically reliable temporal efficiency of the three products. We also presented the relative efficiency and recognizable features of the products. We highlighted the significantly prompt and long release larvicide effects of the drugs. We discussed and compared the information content of the applied statistical methods.

Larvicidal activity of Dalbergia brasiliensis (Fabaceae - Papilionoideae) on Aedes aegypti

Dengue is a viral infectious disease, transmitted by mosquito of the genus Aedes. This work describes the in vivo toxicity analysis of the crude EtOH extract (EEC), hexanic (HF), chlorophormic (CF), ethyl acetate (EAF) fractions, of bark and leaves, and isoflavonoids, from Dalbergia brasiliensis, an arboreal species with wide distribution in Brazilian territory. When considering the issue of controlling the vector Aedes aegypti, the investigation of natural products shows as an important field once natural products can demonstrate fast and effective activity and less environmental impact than synthetic compounds. In this context, we evaluated the activity of the crude extract and fractions of Dalbergia brasiliensis in larvae on the third developmental stage. Five concentrations (0; 125; 250; 500 and 1000 µg/ml) were used on the assays, with 4 repetitions for each treatment, using fifteen 24 h exposed larvae for each repetition. The assays showed that all extracts, fractions and isoflavonoids induced mortality, indicating a larvicidal effect. However, when comparing the results, it becomes evident that the chlorophormic fraction of the bark (BCF) and ethyl acetate fraction of the leaves (LEAF) were the most active, with DL 50 barely 25 and 24 μg/ml, respectively. External morphological alterations were verified in all larvae exposed to D. brasiliensis, after a 24 h exposure. The main alterations observed for the extracts were rigid but easily breakable exoskeleton and elongation of the anterior portion to the thorax. The results observed in this work shows that Dalbergia brasiliensis has an important larvicidal potential. Key words: Dalbergia brasiliensis, larvicidal activity, Aedes aegypti, Jacaranda.

The essential oil from Vanillosmopsis arborea Baker (Asteraceae) presents antinociceptive, anti‐inflammatory, and sedative effects

Background: The essential oil from Vanillosmopsis arborea (EOVA) Baker is rich in (‐)‐α‐bisabolol. Investigations demonstrated its gastroprotective, larvicidal, and visceral antinociceptive activities. Aims: The present study aimed to elucidate the antinociceptive, anti‐inflammatory and sedative properties of the EOVA Baker in mice. Materials and Methods: The antinociceptive and anti‐inflammatory activities were assessed using the abdominal constriction, formalin and carrageenan‐induced paw edema models,respectively. The sedative property was detected by the open‐field and sleeping time tests. Results were analyzed by ANOVA, followed by Student‐Newman–Keuls test. Results: EOVA, after intraperitoneal administration, produced an inhibition of the acetic acid‐induced writhing in mice. In addition, the same doses were able to inhibit both the early and late phases of the formalin‐induced nociception. EOVA produced inhibition in the carrageenan‐induced edema model, reduced the spontaneous motor activity and prolonged the sleeping time induced by pentobarbital. Conclusion: The experimental data demonstrated that EOVA showed antinociceptive,anti‐inflammatory, and sedative activities. Key words: Anti-inflammatory agents, antinociceptive agents, essential oils, sedative effect

Isolation and studies on chemotherapeutic potential of aloin

Background: Plant‑derived phytochemicals are gaining wide popularity owing to their diverse therapeutic potential and less side‑effects. Aloin is one of the plant‑derived flavonoids. Rutin has demonstrated cardioprotective, analgesic, and anticancer effects. Aim: The current work was focused to evaluate bioactive potential of aloin. Materials and Methods: Aloin was isolated from tobacco leaves. The structure was confirmed by H1 NMR spectroscopy. The isolated aloin was studied for possible antibacterial, antifungal, anthelmintic, larvicidal, and cytotoxic effects. Statistical Analysis Used: The results are expressed as mean ± standard error of the mean. Experiments were always performed in triplicates. Statistical comparison was performed using analysis of variance followed by Bonferroni’s test (*P < 0.05). Results and Conclusions: Results of studies demonstrated that rutin effectively inhibited the growth of bacteria and fungi, as well as it also demonstrated the anthelmintic potential. There was a positive response for larvicidal and cytotoxic effects. These studies justify chemotherapeutic potential of aloin. Key words: Aloin, antibacterial, antifungal, anthelmintic, larvicidal, cytotoxic