Potential mosquito repellent compounds of Ocimum species against 3N7H and 3Q8I of Anopheles gambiae

Abstract

Mosquitoes are exceptionally efficient in detecting their hosts for blood meal using odorant binding proteins, viz. 3N7H and 3Q8I and spread several dreadful diseases. DEET is a synthetic mosquito repellent widely used all over world for protection against mosquito bite. Reports reveal that, synthetic mosquito repellents may pose health problems in considerably large population. In view of the above fact, we made an attempt to discover efficient and novel natural mosquito repellent compounds with least impact on human health. Methanolic leaf extracts of Ocimum basilicum Linn. var. pilosum (willd.)-Benth and Ocimum tenuiflorum var. CIM-AYU were subjected to GC–MS analysis and obtained 35 phytochemical constituents. Repellent potentiality of the Ocimum compounds was assessed against 3Q8I and 3N7H of Anopheles gambiae. PDB structures of mosquito odorant binding proteins were downloaded, processed and docking studies were performed along with reference ligand DEET using Schrodinger MAESTRO 9.2 software. Molecular docking results reveal that phenol, 2-methoxy-3-(2-propenyl)-, licopersin, gamma sitosterol and benzene, 1,2-dimethoxy-4-(2-propenyl)- from O. tenuiflorum var. CIM-AYU are strongly bound with 3N7H. Whereas, 4h-1-benzopyran-4-one, 5-hydroxy-6,7-dimethoxy-2-(4-methoxyphenyl)-, catechol and monoacetin from O. basilicum Linn. var. pilosum (willd.)-Benth. show high binding affinity with odorant binding protein 3Q8I. All natural compounds tested in the present study display better docking scores than DEET. The results further substantiate that the 12 out of 35 compounds of the two Ocimum species found to be ideal candidates for design and development of potential mosquito repellents. ADME properties of the tested compounds further confirm that bioactive compounds of Ocimum species were found to be in acceptable range. Synchronized application of at least two different natural compounds (with best docking scores) which target 3N7H and 3Q8I (Odorant Binding Proteins of mosquito) proteins may provide enhanced protection against mosquitoes bite. Based on the ADME properties, natural compounds of Ocimum species can be considered for design and development of safe mosquito repellents.Electronic supplementary materialThe online version of this article (doi:10.1007/s13205-015-0346-x) contains supplementary material, which is available to authorized users.

Identification of Potential Inhibitors from Pyriproxyfen with Insecticidal Activity by Virtual Screening

“…All molecules tested in the present study exhibit hydrogen bonding and also display hydrophobic interactions with corresponding amino acids, according to the molecular docking simulations performed here (see Section 2.3). All the molecules investigated here did not present any violation, except for the template compound (pyriproxyfen), but they are in accordance with Lipinski’s rule of five, and only five molecules violated Jorgensen’s rule of three, which is in accordance with studies carried out by Gaddaguti et al (2016) [25]. Compounds with less, or preferably no violations, of these rules are more likely to be administered/available by the oral route [25].…”

“…For the ligand it was possible to see hydrogen bonds in common with the residues Tyr124, Glu202, and Ser203. There were also hydrophobic interactions with residues Trp86, Gly121, and Tyr337, as identified in studies conducted by Gaddaguti et al (2016) [25].…”

“…The toxicological properties of the molecules with toxicity alarms are shown in Table 2. It was noted that the pyriproxyfen in the toxicity analysis did not indicate any alert, a fact that can be justified considering the low concentration in which it acts in the active site [25,26,27].…”

Field Efficacy Evaluation of some Ethnomedicinal Plants Smoke Repellency Against Anopheles arabiensis and Aedes Aaegypt

“…There are well-established variations in the susceptibility of mosquito species to synthetic repellents like DEET [32]. DEET is a synthetic mosquito repellent widely used all over the world for protection against mosquito bites [33]. Because of concerns about the side effects of DEET, the U.S. Centres for Disease Control and Prevention (CDC) licensed plant-based mosquito repellents, one of which was para-Menthane-3,8-dio(PMD) [34].…”

Biological Control of Mosquito Vectors

“…Aedes Eegyptii is a noteworthy vector which transmits dengue and chikungunya, affecting more than 2.5 million individuals each year [5]. Anopheles mosquito is the major cause of malaria and it spreads vivax, grassi, protozoan parasites, and plasmodium falciparum in the host organism [6].…”