Being an extremophile love, my PhD work mainly involved bioprospecting of thermophilic microbes from hot springs of West Bengal. Extermophiles are organisms which can grow at environments which are deemed extreme by us for habitatation and thermophilic microbes are those organisms which can grow at extremely high temperatures having a growth optima above the normal mesophilic range of 25°C-45 °C. I searched for microbes having useful biotechnological potential and worked extensively on them. The two most famous hot springs of West Bengal are the Paniphala hot spring and the Bakreshwar hot spring and my work encompassed on bioprospecting them. 

Carotenoid pigments are colourful pigments naturally found in plants, prokaryotes (bacteria and archaea) and fungus. I set to work on them from thermophilic bacteria isolated from hot springs of West Bengal as they can be more heat stable being isolated from hot environments. Carotenoids have numerous roles and uses. It helps in photosynthesis, photoprotection, imparts colour to the organism containing it. Now-a-days, we are want to replace toxic synthetic dyes with naturally found colourful pigments as an environment friendly alternative and carotenoids have been successful many times on an experimental level and hopefully its industrial use will also increase manifold in near future. Not only that, carotenoids have antioxidant properties, semi-conductor health benefits, membrane stabilization and signalling properties. Carotenoids act as precursors of important biological molecules as Vitamin A or retinoid. They also have  potential in organic electronics and renewabe energy devices. For further information on my work on carotenoids and carotenoid producers, these publications can be referred.

https://link.springer.com/article/10.1186/s41110-017-0032-3

https://journals.asm.org/doi/full/10.1128/genomeA.00629-16

https://annalsmicrobiology.biomedcentral.com/articles/10.1186/s13213-020-01558-9

https://pubs.rsc.org/en/content/articlehtml/2022/ma/d1ma01070k

From the hot springs of West Bengal, several plant growth promoting organisms were isolated. The key factor behind using hot spring as a sample source was to get organisms which can help plants to tolerate high temperatures. Among all the organisms, one organism was particularly found to be a polyvalent plant growth promoting organism capable of increasing rice plant growth and yield. For further information on this work the following publication can be refered.

https://link.springer.com/article/10.1007%2Fs00284-020-02032-0

Thermophiles are a great source of thermozymes i.e. heat stable enzymes. These enzymes are of high demand industrially. Most of my work comprised on thermostable cellulases and lipases.  I also worked on the diversity analysis, metaproteome study of selective enzymes and cloning, purification, characterization  and bioinformatic study of some of the thermophilic enzymes. I was also part of a whole genome sequencing project involving extremophiles from different regions. Some of the works are as follows:

https://annalsmicrobiology.biomedcentral.com/articles/10.1186/s13213-020-01558-9

https://journals.asm.org/doi/full/10.1128/genomeA.00629-16

https://scholar.google.com/scholar?cluster=15957198635072082971&hl=en&oi=scholarr

https://www.researchgate.net/profile/Ipsit-Hauli/publication/258149294_Isolation_and_identification_of_a_novel_thermo-alkaline_thermostable_SDS_and_chelator_resistant_amylase_producing_Anoxybacillus_sp_IB-A_from_hot_spring_of_Bakreswar_West_Bengal_India_First_report/links/0c9605273491f4226b000000/Isolation-and-identification-of-a-novel-thermo-alkaline-thermostable-SDS-and-chelator-resistant-amylase-producing-Anoxybacillus-sp-IB-A-from-hot-spring-of-Bakreswar-West-Bengal-India-First-report.pdf

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.881.7079&rep=rep1&type=pdf

https://journals.asm.org/doi/full/10.1128/genomeA.01202-16

https://journals.asm.org/doi/full/10.1128/genomeA.01017-16

https://www.frontiersin.org/articles/10.3389/fmicb.2021.672727/full

https://www.researchgate.net/profile/Bidisha-Sarkar/publication/258149426_L-Tryptophan_production_by_a_psychrophilic_Pseudomonas_sp_023K_A_new_report/links/00b7d527348617a69d000000/L-Tryptophan-production-by-a-psychrophilic-Pseudomonas-sp-023K-A-new-report.pdf

Piezophiles are organisms which can grow optimally at high hydrostatic pressures at deep-sea hydrothermal vents. My present work is centered on the project PIEZOPRO which comprises of working on investigation of adaptations by deep-sea piezophile under high pressure conditions, and the biotechnological potential of molecules responsible for such adaptations.  The project uses Thermococcus barophilus as a model piezophile. It is seen, that in T. barophilus, high pressure influences the energy metabolism by repressing many amino acid biosynthetic pathways and upregulating carbohydrate metabolism. Thus the amino acid requirement of this organism increases under high pressure. It is still not clear, how the organism obtains the necessary amino-acids for its growth. This project intends to determine whether protease production is one of the unique adaptation features of piezophiles to counteract the effects of the down regulation, and make up for this amino acid deficiency. Furthermore, the most stable and metabolically significant protease identified from T. barophilus will be subjected to purification and structural characterization studies as extremophilic proteases are extremely important components of the commercial enzyme sector.  Watch this space as more information becomes available!

This project comprises of characterization of microbes from a patented anaerobic biogas reactor and studying its microbial dynamics. Watch this space as more information becomes available.