Phytofabrication of silver nanoparticles using Annona reticulata and assessment of insecticidal and bactericidal activities

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.

Identification of pheromone-carrying protein in the preorbital gland post in the endangered Indian male Blackbuck Antelope cervicapra L.

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.

Diversity and community structure of butterfly of Arignar Anna Zoological Park, Chennai, Tamil Nadu.

Investigation was carried out on the diversity of butterfly fauna in selected localities of conservation and breeding center of Arignar Anna Zoological Park (AAZP), Chennai, Tamil Nadu. A total of 56 species were recorded, 15 of them belonged to Pieridae, 12 Nymphalidae, 9 Satyridae, 8 Papilionidae, 7 Danaidae, 3 Lycaenidae and 1 species each belonged to the families Acraeidae and Hesperidae. Qualitatively and quantitatively Pieridae family were comparatively dominant than that of other families. The notable addition to the 25 more species listed during this observation were compared to previous field survey. Comparison of butterfly species distribution between the different localities revealed that butterfly species richness was higher at mountain region with 52 species and lowest of 25 species at public visiting areas. Visitor’s activities may be that reason for effects on butterfly distribution and lack of vegetation. Each five endemic and protected species (i.e. endangered) listed under the Wildlife (Protection) Act were highlighted greater conservation importances of the AAZP. It is suggest that butterfly species diversity generally increase with increase in vegetation and declines with the increase in disturbance.

Comparison of physico-chemical parameters and phytoplankton species diversity of two perennial ponds in Sattur area, Tamil Nadu.

Investigations were carried out on the diversity of phytoplankton in relation to physico-chemical parameters with respect to pollution status of two perennial ponds of Sattur area, Tamil Nadu. Fifty species were identified belonging to Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae. High value of physico-chemical parameters and low phytoplankton diversity were recorded in the Chinnapperkovil pond, whereas low value of physico-chemical parameters and high phytoplankton diversity were recorded in the Nallanchettipatti pond. Class Chlorophyceae qualitatively and quantitatively dominated in both the habitats when compared to other taxa. Present study revealed that phytoplankton species richness (R1 and R2) was comparatively higher (R1: 5.43±0.53; R2: 3.00±0.27) in Nallancheettipatti pond. The species diversity was high (H’: 3.08±0.37; N1: 14.05±0.63; N2: 12.55±0.94) in Nallanchettipatti pond compared to Chinnapperkovil pond (H’: 2.25±0.15; N1: 12.59±0.80; N2: 8.54±0.61). Anabaena aequalis, Nitzschia bilobata, Navicula membranacea, Scenedesmus annatus, Pediastrum leonensis, Frustulia rhomboides, Microcystis aeruginosa, Oscillatoria angusta, Closterium acerosum species dominated in Chinnapperkovil pond and Spirogyra maxima, Zygnema caeruteum and Fragilaria oceanica dominated in Nallanchettipatti pond. Abundance of such specific taxa (e.g. Closterium acerosum, C. dianae, C. lineatum, Anabaena aequalis, Oscillatoria angusta and Navicula membranacea) in the Chinnapperkovil and Nallanchettipatti (e.g. Merismopedia glauca and Fragilaria oceanica) ponds suggests that these taxa can be considered as pollution indicators. Phytoplankton species diversity and physico-chemical parameter profiles indicate the Chinnapperkovil pond to be meso-eutrophic whereas the Nallanchettipatti pond is oligo-eutrophic.

Zooplankton diversity and physico-chemical conditions in three perennial ponds of Virudhunagar district, Tamilnadu.

Plankton diversity and physico-chemical parameters are an important criterion for evaluating the suitability of water for irrigation and drinking purposes. In this study, we tried to assess the zooplankton species richness, diversity, and evenness and to predict the state of three perennial ponds according to physico-chemical parameters. A total of 47 taxa were recorded: 24 rotifers, 9 copepods, 8 cladocerans, 4 ostracods and 2 protozoans. More number of zooplankton species were recorded in Chinnapperkovil pond (47 species) followed by Nallanchettipatti (39 species) and Kadabamkulam pond (24 species). Among the rotifers, Branchionus sp. is abundant. Diaphanosoma sp. predominant among the cladocerans. Among copepods, numerical superiority was found in the case of Mesocyclopes sp. Cypris sp. repeated abundance among ostracoda. Present study revealed that zooplankton species richness (R1 and R2) was comparatively higher (R1: 4.39; R2: 2.13) in Chinnapperkovil pond. The species diversity was higher in the Chinnapperkovil pond (H’: 2.53; N1: 15.05; N2: 15.75) as compared to other ponds. The water samples were analyzed for temperature, pH, electrical conductivity, alkalinity, salinity, phosphate, hardness, dissolved oxygen and biological oxygen demand. Higher value of physico-chemical parameters and zooplankton diversity were recorded in Chinnapperkovil pond as compared to other ponds. The zooplankton population shows positive significant correlation with physico-chemical parameters like, temperature, alkalinity, phosphate, hardness and biological oxygen demand, whereas negatively correlated with rainfall and salinity. The study revealed that the presence of certain species like, Monostyla sp., Keratella sp., Lapadella sp., Leydigia sp., Moinodaphnia sp., Diaptomus sp., Diaphanosoma sp., Mesocyclopes sp., Cypris sp. and Brachionus sp. is considered to be biological indicator for eutrophication.