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The present work deals with, the potential of biosorption technique for the removal of chromium from aqueous solutions using marine based material viz. Gracilaria corticata powder. The experiments are carried out in a batch operation to understand the equilibrium studies, kinetics and thermodynamics of the biosorption. The maximum removal efficiency of 93.68% was obtained at a temperature of 323 K, pH 4, equilibrium time of 240 min and at an optimum biosorption dosage of 20 g/L of 44 µm particle size. The percentage biosorption increases with an increase in initial concentration of chromium. The statistical analysis of biosorption using Response Surface Methodology (RSM) was studied. The theoretical and experimental values for % biosorption of chromium were observed as 85.39% and 85.49% respectively. It is evident that experimental values of % biosorption are in close agreement with that values predicted by Central Composite Design. The experimental data are well described by Freundlich, Langmuir and Redlich isotherm models. The biosorption data follows pseudo second order kinetics. Thermodynamic results showed that biosorption is endothermic, irreversible and feasible.

Removal efficiency of phenol from aqueous solutions was determined using Pseudomonas putida (NCIM 2102). Experiments were made as a function of pH (4 - 9), temperature (28 - 36^oC), and agitation speed (100 - 200 rpm). Optimization of these three process parameters for phenol degradation was studied. Statistically designed experiments using response surface methodology was used to get more information about the significant effects and the interactions between these three parameters. A 23 full-factorial central composite design was employed for experimental design and for analysis of the results. A second order polynomial regression model, has been developed using the experimental data. It was found that the degrading potential of P.putida (NCIM 2102) was strongly affected by the variations in pH, temperature and agitation speed. The experimental values were in good agreement with the predicted values and the correlation coefficient was found to be 0.9871. The optimum process conditions for maximizing phenol degradation were recognized as follows: pH (7.49), temperature (29.99^oC), and agitation speed (138.89) rpm

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Sugar industrial effluents possess high amounts of toxic pollutants and contaminate the receiving sites. Treatment of contaminated sites by using microorganisms provides an alternate to conventional methods hence demands in the identification of metal tolerant microorganisms has been increasing day by day. Therefore in this study soil samples collected from Tanuku sugar factory residual effluent point (bank of Gosthani river), west Godavari district A.P were analyzed for the bacterial tolerance to Copper (Cu), Zinc (Zn) and Lead (Pb) in their chloride forms. Additionally, the study was carried out to identify the metal tolerant bacteria by morphological, biochemical and 16S rRNA gene sequencing studies. Four potential bacterial isolates were selected to analyze metal tolerance against CuCl2, ZnCl2, and PbCl2. The sequences were compared with those in NCBI and submitted in gene bank with accession numbers MK100333 (Paenibacillus cookie), MK100334 (Bacillus cereus), MK100335 (Aneurini bacillus sp) and MK100387 (Paenibacillus sp.). A Phylogenetic tree was constructed to Paenibacillus sp. the highly efficient bacterial strain among the four isolates using MEGA 7 soft ware. The results of this study showed that P. dentritiformis had multiple metal tolerances (Cu, Zn and Pb) up to 500mg/L after 72 hrs.  The identified bacterial strain proved to be the strong heavy metal tolerant bacterial strain. Hence, its usage will be helpful in the treatment of heavy metals specifically Cu, Zn and Pb contaminated soils and further optimization of these cultures is required to improve its metal resistant capacity.