Sains Malaysiana 43(3)(2014): 443–449

 

Effects of Mg2+, Fe3+, Mn2+ and Cu2+ Ions on Lipid Accumulation by

Cunninghamella bainieri 2A1

(Kesan Ion Mg2+, Fe3+, Mn2+ dan Cu2+ dalam Pengumpulan Lipid oleh Cunninghamella bainieri 2A1)

 

VIDYAH MANIKAN1, MOHD SAHAID KALIL2, OTHMAN OMAR1, ABDUL JALIL ABDUL KADER3 & AIDIL ABDUL HAMID*1

 

1School of Biosciences and Biotechnology, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

 

2Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

 

3Faculty of Science and Technology, Universiti Sains Islam Malaysia, 71800 Nilai,

Negeri Sembilan, Malaysia

 

Received: 8 December 2012/Accepted: 11 July 2013

 

ABSTRACT

 

Cunninghamella bainieri 2A1 is an oleaginous fungus whose lipid accumulation profile is significantly influenced by metal ion concentrations in growth medium. Mg2+, Fe3+, Mn2+ and Cu2+ were found to be the important elements affecting lipid accumulation in this fungus. This study employs a statistical method (Response Surface Methodology – RSM) to study the combined effects of Mg2+, Fe3+, Mn2+ and Cu2+ on lipid accumulation of C. baineri 2A1. Cultivation was carried out in 250 mL Erlenmeyer flasks containing 100 mL nitrogen limited medium at 30ºC and 250 rpm agitation for 120 h. A thirty-run central composite design experiment was employed to identify and optimize the significant factors. In addition to Mg2+ and Fe3+ which were shown to have significant effects on lipid accumulation, the interactions between Mg2+ and Cu2+, as well as the effect of Cu2+ in quadratic terms were also found to have significant effect on the process (p<0.05). The highest amount of lipid obtained in this study was 39% g/g biomass with optimal levels of Mg2+, Fe3+ and Cu2+ at 5.00, 0.017 and 0.0005 g/L, respectively, while Mn2+ was omitted. A 32% increment in lipid yield was recorded, where the lipid content increased to 38%, compared to initial yield of 29% g/g biomass prior to optimization. In conclusion, Mg2+ and Fe3+ have significant positive effect on the lipid accumulation of this fungus, whereas Mn2+ and Cu2+ exert negative effects in combination.

 

Keywords: Cunninghamella; metal ions; response surface methodology; single cell oil

 

ABSTRAK

Cunninghamella bainieri 2A1 merupakan kulat oleaginous dengan profil pengumpulan lipidnya dipengaruhi secara signifikan oleh kepekatan ion logam dalam medium pertumbuhan. Mg2+, Fe3+, Mn2+ dan Cu2+ adalah elemen penting yang mempengaruhi proses pengumpulan lipid dalam kulat ini. Kajian ini membabitkan penggunaan kaedah statistik (RSM) untuk mengkaji kesan kombinasi Mg2+, Fe3+, Mn2+ dan Cu2+ ke atas pengumpulan lipid oleh C. baineri 2A1. Pengkulturan dilakukan dalam kelalang goncangan 250 mL yang mengandungi 100 mL medium terhad nitrogen pada suhu 30ºC dengan kadar goncangan 250 rpm. Set eksperimen yang terdiri daripada 30 larian reka bentuk gubahan memusat telah digunakan untuk mengenal pasti dan mengoptimumkan faktor yang signifikan. Di samping Mg2+ dan Fe2+ yang didapati mempunyai kesan yang signifikan ke atas proses pengumpulan lipid, interaksi antara Mg2+ dan Cu2+ serta kesan Cu2+ pada terma kuadratik juga mempunyai kesan yang signifikan dalam proses ini (p<0.05). Peratus lipid maksimum yang tercapai adalah sebanyak 39% g/g biojisim dengan tahap optimum bagi Mg2+, Fe3+ dan Cu2+ pada kepekatan 5.00, 0.017 dan 0.0005 g/L masing-masing, manakala Mn2+ tidak dimasukkan. Peratus peningkatan penghasilan lipid adalah sebanyak 32% dan ia meningkat kepada 38% berbanding dengan 29% g/g biojisim sebelum pengoptimuman. Kesimpulannya, Mg2+ dan Fe3+ mempunyai kesan positif yang signifikan ke atas proses pengumpulan lipid oleh kulat ini, manakala Mn2+ dan Cu2+ mempunyai kesan negatif secara kombinasi.

 

Kata kunci: Cunninghamella; ion logam; kaedah gerak balas permukaan; minyak sel tunggal

REFERENCES

Aidil, A.H., Wan, M.W.Y., Rosli, M.I. & Kalaivani, N. 2001. Screening of new fungi strains from Malaysia soil for γ-linolenic acid (GLA) production. Jurnal Teknologi34: 1-8.

Box, G.P., Flunter, W.G. & Flunter, J.S. 1978. Statistics for Experiments: An Introduction to Design, Data Analysis and Model Building. New York: John Wiley and Sons Inc.

Dyal, S.D. & Narine, S.S. 2005. Implications for the use of Mortierella fungi in the industrial production of essential fatty acids. Food Research International 38: 445-467.

Farhila, M., Nawi, W.N.N., Kader, A.J., Wan, M.W.Y. & Aidil, A.H. 2008. Effects of metal ion concentrations on lipid and gamma linolenic acid production by Cunninghamella sp. 2A1. Online Journal of Biological Sciences 8(3): 62-67.

Folch, J., Lees, M. & Sloane-Stanley, G.H. 1957. A simple method for isolation of total lipids from animal tissues. Journal of. Biochemistry 226: 497-509.

Jasper, P. & Silver, S. 1997. Magnesium transport in microorganisms. Microorganisms and Minerals. New York: Marcel Dekker Incorporation.

Kendrick, A. & Ratledge, C. 1992. Lipids of selected molds grown for production of n-3 and n-6 polyunsaturated fatty acids. Lipids 27: 15-20.

Lilly, V.G. 1965. Chemical constituents of the fungal cell. In The Fungi. An Advanced Treatise, edited by Ainsworth, G.C. & Sussman, A.S. New York: Academic Press. pp.163-173.

Pirt, S.J. 1975. Principle of Microbe and Cell Cultivation. New York: Wiley.

Ratledge, C. 1997. Microbial lipids: Product of secondary metabolism. Biotechnology 7: 135-197.

Ratledge, C. 2004. Fatty acid biosynthesis in microorganisms being used for single cell oil production. Biochimie 86: 807-815.

Ratledge, C. 2005. Single cell oils for the 21st century. In Single Cell Oils, edited by Cohen, Z. & Ratledge, C. Illinois: AOCS Press.

 

 

*Corresponding author; email: aidilah@pkrisc.cc.ukm.my

 

 

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