e-Περιοδικό Επιστήμης & Τεχνολογίας

e-Journal of Science & Technology, (e-JST)


Taguchi experimental design for medium optimization for enhanced protease production by Bacillus subtilis HB04


C.K. Venil1 and P. Lakshmanaperumalsamy2


1Division of Environmental Microbiology, Department of Environmental Sciences,

Bharathiar University, Coimbatore – 641 046, Tamil Nadu, India.

2Karpagam University, Coimbatore – 641 021, Tamil Nadu, India.

Email: ckvenil@gmail.com; drplpsamy@gmail.com




Bacillus sp. is specific producers of proteases amongst bacteria and protease enzymes are of significant ones due to their multifarious applications. In this research,Taguchi experimental design was applied to optimize the conditions for protease production by Bacillus subtilis HB04.  This approach facilitated the study of interaction of a large number of variables spanned by factors and their settings with a small number of experimental runs leading to considerable economy in time and cost for the process optimization.  The objective of this research was to determine the significant parameters in the production of protease by Bacillus subtilis HB04 in submerged fermentation.  Five factors viz., carbon, nitrogen, metal ions, temperature and agitation, each at four levels were selected and an orthogonal array layout of L16 (45) performed.   The experiment result indicated that dextrose (1 %), (NH4)2PO4 (0.5 %), temperature (30oC) and agitation (100 rpm) were the important factors for protease production by Bacillus subtilis HB04 in submerged fermentation at the optimum levels.


Keywords: Bacillus subtilis HB04; Protease; Taguchi design; contribution