ABSTRACT
Aim: Silver nanoparticle synthesis using plant products is now popular due to its environment friendly, easy availability, simple procedure and fascinating properties. In this study, an attempt was made on leaf extract of Annona reticulata L silver nanoparticles to synthesize and to assess its bactericidal and insecticidal properties. Methodology: Using plant material for silver nanoparticle synthesis is one of the bottom up approaches of silver nanoparticle synthesis. In the present study leaf extract of Annona reticulata was used for nanoparticle synthesis. The synthesized nanoparticles were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and Energy Dispersive X-Ray Analysis (EDAX). The bactericidal property was evaluated against E. coli, P. aeruginosa, S. aureus, B. subtilis and P. vulgaris where as insecticidal property was tested against mosquito larvae and Sitophilus oryzae. Results: The XRD spectrum confirmed the formation of silver nanoparticles. SEM observation showed that nanoparticles were 17.33 nm in size and spherical in shape. The EDAX result revealed the presence of silver in the suspension. Silver nanoparticles exhibited higher repellency against Sitophilus oryzae and feeding deterrence. The nanoparticles possessed a strong larvicidal activity when they were used against fourth instar larvae of mosquitoes. The silver nanoparticles showed bactericidal activity against Pseudomonas aeruginosa, Proteus vulgaris, Bacillus subtilis, Staphylococcus aureus and Escherichia coli. Interpretation: The present study strongly suggests that Annona reticulata leaf extract can be used to fabricate silver nanoparticles with potent insecticidal and bactericidal properties.
ABSTRACT
In mammals, a low molecular mass protein (17-20 KDa) reported from the pheromone sources such as urine, saliva, glandular secretion, etc., as ligand-carrier (pheromone carrier) has been associated with chemo-communication. Since the preorbital gland post is one of the major pheromone sources in Indian Blackbuck, an endangered species, we assumed thta it possibly contains low molecular mass protein for chemical communication. Hence, we investigated the preorbital gland post in territorial and non-territorial male blackbucks for such low molecular mass proteins adopting SDS-PAGE and LC-MS/MS analysis. The total content of protein was higher in the post of territorial males than non-territorial males of adult and sub-adult. In fact, the protein profiles such as 17, 21, 25, 42 and 61 kDa were noted in the gland secretion of territorial and non-territorial males. The intensity of the 17 kDa protein band was higher in territorial males than non-territorial males. In-gel trypsin digestion of the 17 kDa band was processed and subjected to LC-MS/MS and SEQUEST analyses. The results of LC-MS/MS and SEQUEST search showed the presence of α2u-globulin in the 17 kDa band. In addition, the identified α2u-globulin sequence possessed GDW residues, which are the characteristic signature for lipocalin family. Since the α2u-globulin has been reported from the pheromone-carrying proteins in some mammals, this protein may carry the volatiles (pheromone compounds) in male Blackbucks preorbital gland to evoke the scent marking for maintaining territoriality (home range) and attraction towards female, through the secretion of glandular protein.
ABSTRACT
The low molecular mass proteins found in the pheromonal sources such as urine, saliva, glandular secretion etc have been reported as ligand carriers for the processes of chemocommunication in mammals. The preputial gland plays an important role in the production of olfactory signals for pheromonal communication. Thus, in the present study, alpha-2u globulin having molecular mass of 18 kDa has been identified in the preputial gland of Norway rat (Rattus norvegicus) by in-gel trypsin digestion and analyzing the resulting peptides by MALDI-TOF. Since preputial gland is one of the major pheromonal sources in rat, the results suggest that alpha-2u globulin might act as a carrier for hydrophobic odorants of preputial gland.