Anticoagulation activity of salivary gland extract of oriental blackfly Simulium indicum

Objective: To study the morphology of the salivary gland of the female blackfly of the species Simulium indicum (S. indicum) along with protein profile and anticoagulant activity of the salivary gland extract. Methods: Sodium dodecyl sulphate polyacrylamide gel electrophoresis was used to analyze the protein profile of the salivary gland extract (SGE) and anticoagulant activities against thrombin, and the extrinsic and intrinsic coagulation pathways were found in S. indicum SGE in the TT, PT and APTT assays, respectively. Results: Results revealed that each gland consisted of a cylindrical U-shaped secretory lobe and a more or less spherical reservoir. The protein contents of whole salivary glands were also quantified and the amount of salivary gland proteins in the adult female S. indicum was found out to be approximately 1.12 ± 0.13 μg/female. At least 16 major and several minor protein bands were detected in the female salivary glands. The molecular masses of these major protein bands were estimated at 69, 65, 61, 58, 44, 42, 39, 33, 30, 28, 27, 26, 23, 21, 18 and 16 kDa, consecutively. Anticoagulant activities were found in S. indicum SGE in all the assays. It was found that SGE prolonged human plasma clotting time in a dose-dependent manner. Factor Xa inhibition was shown by the SGE of S. indicum. Percent inhibition value was 93.8. A positive correlation (r=0.89) was observed between total protein and percent inhibition of factor Xa. Conclusions: The present study demonstrated that the mode of action of the anticoagulant(s) is mainly on the inhibition of thrombin and factor Xa along with other target factors of the coagulation cascade

Morphological and molecular diversity of endophytic Colletotrichum gloeosporioides from tea plant, Camellia sinensis (L.) O. Kuntze of Assam, India

Thirty isolates of endophytic fungi were isolated from healthy asymptomatic leaves of tea plant (Camellia sinensis) and identified morphologically based on colony morphology, spore shape and size, growth and sporulation rate. Internal transcribed spacer r-DNA sequence analysis supported for molecular identification of all the isolates. Based on morphological and molecular characteristics the isolates were identified as Colletotrichum gloeosporioides. Variations on colony morphology which included the production of conidial masses, led to divide the isolates into different groups. Variations on spore size, growth rate and sporulation rate were exhibited by all the isolates. With RAPD molecular markers, genetic variations among the thirty isolates were observed. Genetic variations and relatedness among the thirty isolates were analyzed with UPGMA phylogram using NTSYS program. Two major groups were obtained among the thirty isolates. Group I comprised of 16 isolates which included three sub groups (Ia, Ib and Ic) and Group II constituted fourteen isolates and it also had three sub groups (IIa, IIb and IIc). A partial co-relationship among the isolates was established on the basis of morphological and molecular based clustering

Diversity of Cultivable Midgut Microbiota at Different Stages of the Asian Tiger Mosquito, <i>Aedes albopictus</i> from Tezpur, India

<div><p><i>Aedes aegypti</i> and <i>Ae</i>. <i>albopictus</i> are among the most important vectors of arboviral diseases, worldwide. Recent studies indicate that diverse midgut microbiota of mosquitoes significantly affect development, digestion, metabolism, and immunity of their hosts. Midgut microbiota has also been suggested to modulate the competency of mosquitoes to transmit arboviruses, malaria parasites etc. Interestingly, the midgut microbial flora is dynamic and the diversity changes with the development of vectors, in addition to other factors such as species, sex, life-stage, feeding behavior and geographical origin. The aim of the present study was to investigate the midgut bacterial diversity among larva, adult male, sugar fed female and blood fed female <i>Ae</i>. <i>albopictus</i> collected from Tezpur, Northeastern India. Based on colony morphological characteristics, we selected 113 cultivable bacterial isolates for 16S rRNA gene sequence based molecular identification. Of the 113 isolates, we could identify 35 bacterial species belonging to 18 distinct genera under four major phyla, namely Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. Phyla Proteobacteria and Firmicutes accounted for majority (80%) of the species, while phylum Actinobacteria constituted 17% of the species. Bacteroidetes was the least represented phylum, characterized by a single species- <i>Chryseobacterium rhizoplanae</i>, isolated from blood fed individuals. Dissection of midgut microbiota diversity at different developmental stages of <i>Ae</i>. <i>albopictus</i> will be helpful in better understanding mosquito-borne diseases, and for designing effective strategies to manage mosquito-borne diseases.</p></div

One-pot facile green synthesis of biocidal silver nanoparticles

The plant root extract mediated green synthesis method produces monodispersed spherical shape silver nanoparticles (AgNPs) with a size range of 15–30 nm as analyzed by atomic force and transmission electron microscopy. The material showed potent antibacterial and antifungal properties. Synthesized AgNPs display a characteristic surface plasmon resonance peak at 420 nm in UV–Vis spectroscopy. X-ray diffractometer analysis revealed the crystalline and face-centered cubic geometry of in situ prepared AgNPs. Agar well diffusion and a colony forming unit assay demonstrated the potent biocidal activity of AgNPs against Staphylococcus aureus , Escherichia coli , Bacillus subtilis , Klebsiella pneumoniae , Pseudomonas diminuta and Mycobacterium smegmatis . Intriguingly, the phytosynthesized AgNPs exhibited activity against pathogenic fungi, namely Trichophyton rubrum, Aspergillus versicolor and Candida albicans . Scanning electron microscopy observations indicated morphological changes in the bacterial cells incubated with silver nanoparticles. The genomic DNA isolated from the bacteria was incubated with an increasing concentration of AgNPs and the replication fidelity of 16S rDNA was observed by performing 18 and 35 cycles PCR. The replication efficiency of small (600 bp) and large (1500 bp) DNA fragments in the presence of AgNPs were compromised in a dose-dependent manner. The results suggest that the Thalictrum foliolosum root extract mediated synthesis of AgNPs could be used as a promising antimicrobial agent against clinical pathogens

Abundance of identified bacterial species belonging to their respective family isolated from the midgut of adult sugar fed female, blood fed female, male and larvae of <i>Aedes albopictus</i>.

<p>Abundance of identified bacterial species belonging to their respective family isolated from the midgut of adult sugar fed female, blood fed female, male and larvae of <i>Aedes albopictus</i>.</p

Diversity indices, total taxa, and Good’s coverage of midgut bacterial isolates of <i>Ae</i>. <i>albopictus</i> from different life stages.

<p>Diversity indices, total taxa, and Good’s coverage of midgut bacterial isolates of <i>Ae</i>. <i>albopictus</i> from different life stages.</p

Occurrence of identified bacterial species from the midgut of A. sugar fed female, B. blood fed female, C. male and D. larvae <i>Ae</i>. <i>albopictus</i>.

<p>Occurrence of identified bacterial species from the midgut of A. sugar fed female, B. blood fed female, C. male and D. larvae <i>Ae</i>. <i>albopictus</i>.</p

Phylogenetic analysis of bacterial isolates from midgut of <i>Ae</i>. <i>albopictus</i>.

<p>Phylogenetic tree based on partial 16S rRNA gene sequences, reconstructed through neighbor joining algorithm using Kimura 2 distance parameter method. The percentage bootstrap values obtained with 1000 replications are denoted at branch node.</p

Abundance of identified bacterial species belonging to their respective phylum isolated from the midgut of adult sugar fed female, blood fed female, male, and larvae of <i>Aedes albopictus</i>.

<p>Abundance of identified bacterial species belonging to their respective phylum isolated from the midgut of adult sugar fed female, blood fed female, male, and larvae of <i>Aedes albopictus</i>.</p