Sains Ma1aysiana 28: 49-57 (1999)                                                                                                               Sains Hayat/

                                                                                                                                                                                Life Science

 

Effect of pH and Agitation on Growth of Bacillus subtilis

 

 

Noorhisham Tan Kofli & Mohd. Sahaid Kalil

Department of Chemical and Process Engineering

Faculty of Engineering, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E. Malaysia

 

 

ABSTRACT

 

The effect of initial pH of medium (6.0,6.5 and 7.2) and agitation (100,200 and 300 rpm) on growth of oxygen sensitive culture of Bacillus subtilis were studied using shake flask cultures. Two type of media used were complex medium (CM) and well defined medium (WDM3). The effect of both parameters and types of media on production of acetoin and 2,3-butanediol were also studied. The maximum growth was detected in experiment with agitation at 300 rpm and pH 6.5 for both CM (2.87 g/l dry weight) and WDM3 (3.33 g/l dry weight). The use of WDM3 gave higher total products (acetoin+butanediol) concentration (0.67 g/l) compare to CM (0.44 g/l)

 

ABSTRAK

 

Kesan pH awal (6.0, 6.5 dan 7.2) dan kesan kelajuan goncangan (100, 200 dan 300 ppm) bagi pertumbuhan kultur Bacillus subtilis yang sensitif kepada oksigen telah dikaji dengan menggunakan kultur kelalang goncangan. Dua jenis media iaitu medium kompleks and medium tertakrif telah digunakan. Kesan kedua-dua parameter ke atas penghasilan acetoin dan 2,3-butanediol juga dikaji. Pertumbuhan maksimum didapati berlaku dalam eksperimen dengan kelajuan goncangan 300 ppm dan pH 6.5 bagi kedua-dua yang menghasilkan biojisim 2.87 g/l berat kering bagi medium kompleks dan 3.33 g/l berat keriang bagi medium tertakrif. Penggunaan medium tertakrif memberikan kepekatan hasil total (acetoin + butanediol) yang lebih tinggi (0.67 g/l) berbanding medium kompleks (0.44 g/l).

 

RUJUKAN/REFERENCES

 

Amanullah, A. 1991. Effects of mixing and scale on the biological performance of an oxygen sensitive culture of Bacillus subtilis: Development Studies. MPhil. Thesis. The University of Birmingham, Birmingham, United Kingdom.

Beranio, P.B. Jr. & Tsao, T. 1993. Optimization of 2,3-Butanediol Production by Klebsiella oxytoca through oxygen transfer rate control. Biotech. Bioeng. 42 : 1263-1269 .

Dahlgren, M.E., Powel, A.L., Greasham, R.L., & George, H.A. 1993. Development of scale down techniques for investigation of recombinat Escherichia coli fermentations: acid metabolites in shake flasks and stirred bioreactors. Biotech. Progress. 9: 580-586

Euler, P., Martinkova, L., Ujkove, E. & Seichert, L. 1991. Application of scale down experiment in the study of citric acid biosynthesis. Folia Microbiol. 36 (5): 493-497

Mankad, T. & Nauman, E.B. 1992. Effect of oxygen on steady state product distributions in Bacillus polymxa fermentations. Biotech. Bioeng. 40 : 413-426

Moes, J., Griot, M., Heinzle, E., Dunn, I.J. & Bourne, J.R. 1985. A microbial culture with oxygen sensitive product distribution as a potential tool for characterizing bioreactor oxygen transport. Biotech. Bioeng. 27: 482-489

Neish, A.C., Blackwood, A.C., Robertson, F.M. & Ledingham, G.A. 1947. Production and properties of 2,3-butanediol xviii: Dissimilation of glucose by Serratia marcescenens. Can. J. Res., 25B: 65-69 

Pirt, S.J. & Callow, D.S. 1958. Exocellular product formation by microorganism in continuous culture 1: production of 2,3-butanediol by Aerobacter aerogenes in a Single Stage Process. J. of App. Bacteriol. 21(2): 188-205

Ramano, P. & Suzzi, G. 1992. The Effect of Saccharomyces cerevisiae strains on the formation of acetaldehyde and acetoin during fermentation. Proceed. Of Tech. Meeting of European Brewing Convention, Zoeterxovole, The Netherlands pp. 231-247

Ramano, P. & Suzzi, G. 1996. Origin and Production of acetoin during wine yeast fermentation. App. And Environ. Microb., 62 (2): 309-315           

Sablayrolles, J.M. & Goma, G.1984. Butanediol production by Aerobacter aerogenes NRRL B199: Initial substrate concentration and aeration agitation. Biotech. Bioeng. 26: 148-155

Zeng, A.P., Biebl, H. & Deckwer, W.D. 1990. 2,3-Butanediol production by Enterobacter aerogenes in continuous culture: Role of oxygen supply. App. Microbiol. Biotechnol. 33: 264-268.

 

 

 

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