Immobilization of Lecitase (Phospholipase A1) in gelatin hydrogel and its stability is studied with a view to utilizing the immobilized enzyme for degumming rice bran oil. Excellent retention of enzyme activity ([80%) is observed in hydrogel containing 43.5% gelatin crosslinked with glutaraldehyde. Compared to the free enzyme which has a broad pH-activity profile (6.5-8.0), the activity of the immobilized enzyme is strongly dependent on pH and has a pH-optimum of pH 7.5. The optimum temperature of enzyme activity increases from 37 to 50°C. Compared to the free enzyme which loses all its activity in 72 h at 50°C, the immobilized enzyme retains its activity in full. The immobilized enzyme has been used efficiently in a spinning basket bioreactor for the degumming of rice bran oil with 6 recycles without loss of enzyme activity. The phosphorus content of the oil decreases from 400 ppm to 50-70 ppm in each cycle. After charcoal treatment and dewaxing, a second enzymatic treatment brings down the phosphorus content to \5 ppm.

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Technologically driven some glass materials are containing metal clusters have attracted quite attention both in cluster research and in possible futuristic applications of such nanoclusters for magnetic or optoelectronic purposes. In this regard, formation of bimetallic alloys and core–shell nanostructures inside a soda-lime glass were prepared by simple ion-exchange methods and further studied by the optical absorption (OA) properties. Further, we made an attempt for the first time the novel route for the synthesis of bimetallic nanoclusters, gold in various doses was directly implanted in a plain soda-lime glass as well as in a copper and silver ion-exchanged soda-lime glass using the tandem accelerator anticipating the core–shell or alloys phase between the metal species. Also, the post implanted gold (Au+) metal ions were investigated by Rutherford backscattering spectroscopy (RBS) analysis performed on the Cu and Ag ion-exchanged samples to confirm the presence of bimetallic clusters formed by ion-exchange during implantation.