Publications by authors named "Moumita Bhaumik"

2 Publications

  • Page 1 of 1

Prenatal arsenic exposure interferes in postnatal immunocompetence despite an absence of ongoing arsenic exposure.

J Immunotoxicol 2020 12;17(1):135-143

Division of Immunology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India.

Arsenic (As) readily crosses the placenta and exposure of the fetus may cause adverse consequences later in life, including immunomodulation. In the current study, the question was asked how the immune repertoire might respond in postnatal life when there is no further As exposure. Here, pregnant mice (Balb/c [H-2]) were exposed to arsenic trioxide (AsO) through their drinking water from time of conception until parturition. Their offspring, 4-week-old mice who had not been exposed again to As, were used for functional analyses of innate, humoral and cellular immunity. Compared to cells from non-As-exposed dam offspring, isolated peritoneal macro-phages (Mϕ) displayed no differences in T-cell stimulating ability. Levels of circulating IgG but not IgG were decreased in As-exposed dam offspring as compared to control offspring counterparts. Mixed-leukocyte reactions (MLR) indicated that CD4 T-cells from the prenatal As-exposed mice were significantly less responsive to allogenic stimulation as evidenced by decreases in interferon (IFN)-γ and IL-2 production and in expression of CD44 and CD69 (but not CD25) activation markers. Interestingly, the Mϕ from the prenatal As-exposed mice were capable of stimulating normal allogenic T-cells, indicating that T-cells from these mice were refractory to allogenic signals. There was also a significant decrease in absolute numbers of splenic CD4 and CD8 T-cells due to prenatal As exposure (as compared to control). Lastly, the impaired immune function of the prenatal As-exposed mice was correlated with a very strong susceptibility to infection. Taken together, the data from this study clearly show that As exposure may continue to perpetuate a dampening effect on the immune repertoire of offspring, even into the early stages of postnatal life.
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December 2020

Production, partial purification and characterization of a proteoglycan bioemulsifier from an oleaginous yeast.

Bioprocess Biosyst Eng 2020 Oct 14;43(10):1747-1759. Epub 2020 May 14.

Department of Biotechnology, Indian Institute of Technology Kharagpur, West Bengal, Kharagpur, 721302, India.

In this study, Meyerozyma caribbica, an indigenously isolated oleaginous yeast, produced in media containing glucose a bioemulsifier that was partially characterized as a proteoglycan based on preliminary analysis. Optimization of carbon:nitrogen (C:N) ratio revealed 30:1 as the suitable ratio for enhanced production. Apart from higher emulsification activity (E: 70-80%), this molecule showed strong emulsion stability over a wide range of pH (2.0-9.0), salinity (0.05%-10%, w/v) and temperature (- 80 °C to + 50 °C). The current study emphasizes on the determination of critical media parameters for improved and stable bioemulsifier production coupled with partial characterization and identification of the molecule. Thus, a proteoglycan-based bioemulsifier with such a stable emulsifying property can serve as a versatile and potential component in food, cosmetics and pharmaceutical formulations.
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October 2020