Enzymatic Clarification of Fruit Juices (Apple, Pineapple, and Tomato) Using Purified Bacillus pumilus SV-85S Xylanase

The xylanase obtained from a hyper-producer Bacillus pumilus SV-85S was purified and characterized to evaluate its potential in industrial applications. Xylanase was purified to homogeneity 25.3-fold with 63.2% recovery using cation-exchange chromatography through CM-Sephadex C-50. The purified xylanase showed a single band on Native-PAGE and a single peak in RP-HPLC confirming its homogeneity. The purified enzyme revealed a single band on SDS-PAGE with a molecular mass of 23.6 kDa, which was confirmed with gel filtration chromatography through Sepharose 6B. The K-m and V-max of the purified xylanase was 1.0 mg/mL and 333.3 IU/mL, respectively. The temperature and pH profiles of the purified xylanase revealed that it was thermo and alkali stable. In recent years due to the overall increase in natural fruit juice consumption, juices have become important from a consumption point of view. However, raw juice is turbid and viscous which tends to settle during storage. Therefore, it must be clarified before commercialization. The efficacy of absolutely purified xylanase was studied on juice enrichment of apples (Malus domestica), pineapples (Ananas comosus L.) and tomatos (Lycopersicum esculentum). The treatment with xylanase lead to an increased juice yield by 23.53% (apple), 10.78% (pineapple), and 20.78% (tomato) as well as having a significant effect on juice clarity by an increase of % transmittance of 22.20, 19.80, and 14.30, respectively. The turbidity and viscosity was also decreased without affecting acid neutrality significantly.