Time filter

Source Type

Chakraborty S.B.,University of Kaposvar | Chakraborty S.B.,University of CalcuttaWest Bengal | Molnar T.,University of Kaposvar | Ardo L.,Research Institute for Fisheries | And 2 more authors.
Turkish Journal of Fisheries and Aquatic Sciences

The effects of the isoflavone genistein and methanol extract of Basella alba leaves were evaluated in Nile tilapia, Oreochromis niloticus on growth and immunostimulation. Adult tilapia (mean weight 39.55 g) was fed diets containing genistein (1 gm/kg) and methanol extract of B. alba (1 g/kg) for 35 days. Basella alba extract treated tilapia showed significantly higher (P<0.05) weight gain, respiratory burst, phagocytic activity, plasma protein content and plasma lysozyme activity compared to fish fed control diet. The B. alba extract treated fish showed the highest final individual mean body weight, final individual length, specific growth rate, hepatosomatic index and total immunoglobulin content. The phagocytic and respiratory burst activities of genistein treated fish were significantly higher (P <0.05) compared to the control group. The weight gain, lysozyme activity and total protein content of genistein treated fish did not differ significantly (P>0.05) from both control and B. alba treated fish. There was no significant difference (P > 0.05) in the food conversion ratio as well among the different treatment groups. The study indicates that B. alba methanol extract might positively influence the growth and protect the health status of tilapia. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey. Source

Mallick S.,West Bengal State University | Dutta A.,West Bengal State University | Chaudhuri A.,West Bengal State University | Mukherjee D.,National Center for Cell Science | And 16 more authors.
Antimicrobial Agents and Chemotherapy

In our previous report, we showed that astrakurkurone, a triterpene isolated from the Indian mushroom Astraeus hygrometricus (Pers.) Morgan, induced reactive oxygen species, leading to apoptosis in Leishmania donovani promastigotes, and also was effective in inhibiting intracellular amastigotes at the 50% inhibitory concentration of 2.5 μg/ml. The aim of the present study is to characterize the associated immunomodulatory potentials and cellular activation provided by astrakurkurone, leading to effective antileishmanial activity in vitro and in vivo. Astrakurkurone-mediated antileishmanial activity was evaluated by real-time PCR and flow cytometry. The involvement of Toll-like receptor 9 (TLR9) was studied by in vitro assay in the presence of a TLR9 agonist and antagonist and by in silico modeling of a three-dimensional structure of the ectodomain of TLR9 and its interaction with astrakurkurone. Astrakurkurone caused a significant increase in TLR9 expression of L. donovani-infected macrophages along with the activation of proinflammatory responses. The involvement of TLR9 in astrakurkurone-mediated amastigote killing has been evidenced from the fact that a TLR9 agonist (CpG, ODN 1826) in combination with astrakurkurone enhanced the amastigote killing, while a TLR9 antagonist (bafilomycin A1) alone or in combination with astrakurkurone curbed the amastigote killing, which could be further justified by in silico evidence of docking between mouse TLR9 and astrakurkurone. Astrakurkurone was found to reduce the parasite burden in vivo by inducing protective cytokines, gamma interferon and interleukin 17. Moreover, astrakurkurone was nontoxic toward peripheral blood mononuclear cells of immunocompromised patients with visceral leishmaniasis. Astrakurkurone, a nontoxic antileishmanial, enhances the immune efficiency of host cells, leading to parasite clearance in vitro and in vivo. Copyright © 2016, American Society for Microbiology. All Rights Reserved. Source

Mukhopadhyay A.,University of CalcuttaWest Bengal | Bhattacharyya T.,University of CalcuttaWest Bengal | Dasgupta A.K.,University of CalcuttaWest Bengal | Chakrabarti K.,University of CalcuttaWest Bengal
Journal of Molecular Catalysis B: Enzymatic

An immobilization technique (using nanotechnology) that imparts psychrostability and enhanced activity to a psychrophilic pectate lyase (PL) has been described here. Pectate lyase from a pyscrophile was supplemented with calcium hydroxyapatite nanoparticles (NP-PL) as a substitute for Ca, (the cationic activator of this enzyme) and entrapped in single walled nanotube (SWNT) based molecular self-assembly. The activity and stability of PL was enhanced both at temperatures as low as 4°C and as high as 80°C in presence of NP and SWNT. The enzyme could be repeatedly released and re-trapped (in SWNT based molecular self-assembly) while retaining significant activity. The immobilized PL (in SWNT based molecular self-assembly), retained its activity after repeated freezing and thawing. This unique capability of SWNT to activate and stabilize a cold active enzyme at temperatures much lower or higher than its optimal range may be utilized for processes that require bio-conversion at low temperatures while simultaneously allowing for shifts to higher temperature. © 2015 Elsevier B.V. Source

Discover hidden collaborations