Euryale ferox Salisbury (E. ferox) is an environmentally and economically important wetland macrophyte.

A novel polymeric bioflocculant was produced by a bacterium utilizing degradation of n-hexadecane as the energy source. The bioflocculant was produced with a bioflocculating activity of 87.8%. The hydrocarbon degradation was confirmed by gas chromatography-mass spectrometry analysis and was further supported with contact angle measurements for the changes in hydrophobic nature of the culture medium. A specific aerobic degradation pathway followed by the bacterium during the bioflocculant production and hydrocarbon utilization process has been proposed. FT-IR, SEM-EDX, LC/MS, and 1H NMR measurements indicated the presence of carbohydrates and proteins as the major components of the bioflocculant. The bioflocculant was characterized for its carbohydrate monomer constituents and its practical applicability was established for removing the heavy metals (Ni2+, Zn2+, Cd2+, Cu2+, and Pb2+) from aqueous solutions at concentrations of 1–50 mg L-1. The highest activity of the bioflocculant was observed with Ni2+ with 79.29 ± 0.12% bioflocculation efficiency.

A bacterium isolated from the activated sludge of an oil refinery of Assam, India retained efficient bioflocculating activity through production of bioflocculant when it was grown on crude oil amended media avoided of any other carbon source.The bioflocculating activity gained from the optimized media broth was 86.2%, which could be enhanced up to 89.1% with the purified bioflocculant. In course of bioflocculant production, the bacterium utilized about 77% of the petroleum hydrocarbons after incubation for 168 h when the activity was found to be the highest. The bioflocculant was efficient in flocculating Ni 2+ , Zn 2+ , Cd 2+ , Cu 2+ and Pb 2+ . The bioflocculant was characterized as a glycoprotein complex by biochemical tests, FT-IR, SEM-EDX and LC/MS analyses. The bioflocculant showed negligible cytotoxicity on testing with L292 cell line indicating tremendous possibility of its use in bioremediation.

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Changes in catechins, caffeine, total polyphenol, theaflavins, and antioxidant activity during CTC processing of black tea from North East India cultivar were studied. Total polyphenol decreased up to 37% with the formation of theaflavins up to 1.8%.