Abstract
Tannase produced optimally on an agroresidue by an Aspergillus niger isolate under submerged fermentation immobilized on sodium alginate beads with 93.6% efficiency was applied for tannin removal from myrobalan/aonla (Phyllanthus emblica) juice. The pH and temperature optima of the immobilized enzyme were found to be 5.4 and 40°C while the corresponding values of the soluble enzyme were 5.8 and 35°C. Maximum tannin removal of 73.6% was obtained at 40°C and 150 rpm in 180 min with 36.6 U/ml of immobilized enzyme while the same amount of the soluble enzyme removed 45.2% of tannin at 37°C and 150 rpm in the same time period. The immobilized beads could be used repeatedly till 7th cycle with 77% efficiency. When preserved at 6°C the beads retained 71.7% of enzyme activity after 60 days. Reduction in vitamin C content, which is responsible for antioxidant property of the fruit, was minimum at only 2% during the treatment.
Keywords: Aspergillus niger, Immobilized tannase, Myrobalan, Submerged fermentation, Sodium alginate
References
- 1.Ibuchi S., Minoda Y., Yamada K. Hydrolysing pathway substrate specificity and inhibition of tannin acyl hydrolase. Agric Biol Chem. 1972;36(9):1553–1562. doi: 10.1271/bbb1961.36.1553. [DOI] [Google Scholar]
- 2.Lekha P.K., Ramakrishna M., Lonsane B.K. Strategies for isolation of potent cultures capable of producing tannin acyl hydrolase in higher titres. Chem Mikrobiol Technol Lebensm. 1993;15:5–10. [Google Scholar]
- 3.Lekha P.K., Lonsane B.K. Comparative titres, location and properties of tannin acyl hydrolase produced by Aspergillus niger PKL 104 in solid state, liquid surface and submerged fermentation. Proc Biochem. 1994;29:497–503. doi: 10.1016/0032-9592(94)85019-4. [DOI] [Google Scholar]
- 4.Cristobal N., Rodiguez R., Sanchez G., Augur C., Flavela Torus E., Lilia A., Prado B., Ramirez C., Equivel C. Microbial tannases: advances and perspectives. Appl Microbiol Biotechnol. 2007;76:47–59. doi: 10.1007/s00253-007-1000-2. [DOI] [PubMed] [Google Scholar]
- 5.Rout S., Banerjee R. Production of tannase under mSSF and its application in fruit juice debittering. Ind J Biotech. 2006;5:346–350. [Google Scholar]
- 6.Haggerman A.E., Butler L.G. Protein precipitation method for determination of tannins. J Agric Food Chem. 1978;26:809–812. doi: 10.1021/jf60218a027. [DOI] [Google Scholar]
- 7.Rajakumar G.S., Nandy S.C. Isolation, purification and some properties of Penicillium chrysogenum tannase. Appl Environ Microbiol. 1983;46(2):525–527. doi: 10.1128/aem.46.2.525-527.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Kierstan M., Bucke C. The immobilization of microbial cells, subcellular organelles and enzymes in calcium alginate gels. Biotechnol Bioengg. 1977;19:387–397. doi: 10.1002/bit.260190309. [DOI] [PubMed] [Google Scholar]
- 9.Sharma S., Bhat T.K., Dawra R.K. A spectrophotometric method for assay of tannase using rhodanine. Anal Biochem. 2000;279(1):85–89. doi: 10.1006/abio.1999.4405. [DOI] [PubMed] [Google Scholar]
- 10.Park N.H., Chang H.N. Preparation and characterization of immobilized naringinase on porous glass beads. J Fermen Technol. 1979;57:310–316. [Google Scholar]
- 11.Mishra P., Kar R. Treatment of grapefruit juice for bitterness removal by amberlite IR 120 and amberlite IR 400 and alginate entrapped naringinase enzyme. J Food Sci. 2003;68(4):1229–1233. doi: 10.1111/j.1365-2621.2003.tb09630.x. [DOI] [Google Scholar]