STUDIES ON SOME BIOCHEMICAL CHANGES DURING CITRIC ACID PRODUCTION IN A SYNTHETIC MEDIUM BY A MUTANT ASPERGILLUS NIGER AB1801
HTML Full TextSTUDIES ON SOME BIOCHEMICAL CHANGES DURING CITRIC ACID PRODUCTION IN A SYNTHETIC MEDIUM BY A MUTANT ASPERGILLUS NIGER AB1801
P. Ghosh, S. Ganguly* and A. K. Banik
Department of Chemical Engineering (Biochemical Engineering Division), University of Calcutta, 92, A. P. C. Road, Kolkata- 700 009, West Bengal, India
ABSTRACT An experimental study was carried out to examine the biochemical changes in the fermentation broth during citric acid production by a mutant Aspergillus niger AB1801. The production of citric acid was increased upto 8th day of fermentation, and then declined. pH decreased continuously, dry cell weight followed continuous increment pattern. Amino nitrogen and urea nitrogen decreased gradually, but ammonical nitrogen increased steadily
Keywords:
Experimental, Biochemical, Fermentation, |
Citric acid
INTRODUCTION:The role of utilization of carbon and nitrogen sources by an organism from the growth medium can be calculated from the estimation of these compounds in the medium of different stages of growth. The growth of the microorganism as well as the quantitative and qualitative yield of the desired products is dependent on the availability of the nutrient and its utilization and physico-chemical environmental in the medium.
So, the studies on the biochemical changes occurring in the medium during the citric acid fermentation process is essential before standardizing the large scale production method.
Many reviews are available on different aspects of biochemical changes in the fermentation broth during citric acid production 1-11.
Considering the facts, our present study was intended to examine the pattern of sugar, ammonical nitrogen, amino nitrogen, urea nitrogen, citric acid concentration, cellular nitrogen, pH changes in the fermentation broth at different time intervals.
MATERIALS AND METHODS
Microorganism: A mutant Aspergillus niger AB1801 developed in our laboratory from a regulatory mutant Aspergillus niger AB100 by induced mutation was used for this study 12.
Composition of synthetic medium for citric acid fermentation : Composition of synthetic medium for citric acid production was as follows: Sucrose, 10%; urea, 0.25%; KH2PO4, 0.15%; MgSO4.7H2O, 0.03%; boric acid, 0.05% mg/L; Ni2+, 10 µg/ml; Co2+, 5 µg/ml; thiamine- HCl, 10 µg/ml; and pH was adjusted to 3.
Physical conditions for the Fermentation: The fermentation was carried out using 1 L. Roux bottle for 9 days with 150 ml fermentation medium with 8 days old 10 ml spore suspension (2.6 X 107 spores/ml) at pH 3.
Determination of pH: pH of the medium was determined with the aid of a previously standardized pH meter (Unicam 9450 model).
Estimation of Residual Sugar: Residual sugar was determined by DNS method as proposed by Miller (1969)13.
Estimation of Residual, Ammonia and Urea Nitrogen: Nitrogen was measured by the micro Kjeldahl method of Allen (1931) 14.
Estimation of Dry Cell Weight (DCW): Dry cell weight was estimated by the method as proposed by Shah et al (2002).
Estimation of Citric Acid: Citric acid was measured according to the method of Marrier and Boulet (1958) 16.
Measurement of Aconitase Activity: Aconitase activity in different stage of fermentation was measured by the method of Kubicek and Rohr (1985) 17.
Estimation of Amino Nitrogen: Amino nitrogen was estimated by descending paper chromatographic method (1961) 18.
Statistical Analysis: Data were analysed by one way ANOVA followed by Dunett’s post hoc multiple comparison test (using Graph Pad Inc., USA).
RESULTS AND DISCUSSION:
FIG. 1: RATE OF ELABORATION OF CITRIC ACID BY ASPERGILLUS NIGER AB1801 IN RELATION TO CHANGES IN pH, SUCROSE UTILIZATION AND CELLULAR GROWTH
(Values were express as mean ± SEM, where n = 6; *p<0.05, **p<0.01 when compared to control)
Fig. 1 showed that there was an initial accelerated growth with high sugar consumption and lowered production followed by rapid sugar utilization with high acidity rate reaching an efficiency of 90% conversation with 9th day. It is also evident from the Fig.1, that the rate of citric acid production increased upto the 8th day of fermentation when it attained the peak value and then decreased again. Maximum cell growth was obtained on 9th day of incubation. pH decreased from 3 to 1.8. Sucrose was utilized upto 90%.
Hossain et al., (1985) said that when large amount of citric acid are lost from the cell, the activity of aconitase increases as a response to decreased intracellular supply of its substrate 19.
FIG. 2: NITROGEN BALANCE DURING CITRIC ACID FERMENTATION BY ASPERGILLUS NIGER AB1801.
(Values were express as mean ± SEM, where n = 6; *p<0.05, **p<0.01 when compared to control)
Fig. 2 indicates that cell nitrogen increased till the end of fermentation. Amino nitrogen decreased gradually. Ammonia nitrogen increased steadily. Urea nitrogen declined rapidly. Total nitrogen content of the broth decreased. Maximally, 98.3% nitrogen was utilized with 9th day of fermentation.
So, it may be inferred from this work that, both carbon and nitrogen are well balanced with respect to their amounts provided and utilized.
REFERENCE:
- Sancluz M A, vierna L and Meza G, Aspergillus niger mutant in the production of citric acid, Rev. Latinoamer. Microbiol. Parasitol.1969, 11(4), 191-197.
- Legisa M and Kidric J, The influence of intracellular pH of spores on citric acid production by Aspergillus niger, J. Biotechnol,1991, 20(3) , 313-317.
- Crolla A and Kennedy K J, Optimization of citric acid production from Candida lipolytica Y-1095 using n-paraffin, J. Biotechnol.2001, 89, 27-40.
- Haq Iul, Ali S, Qadeer MA and Iqbal J, citric acid fermentation by mutant strain of Aspergillus niger GCMC-7 using molasses based medium, EJB Electronic J. Biotechnol.2002, 5(2) , 125-132.
- Selahzadeh R M and Roehr M, Citric Acid Fermentation and effect of Temperature, Acta Biotechnol., 23(1) (2003) 95-100.
- Murad A, Holi E I, Khalaf S and Delaimy A I, citric acid production from whey with suggrs and additives by Aspergillus niger , Afr. J. Biotechnol.2003, 2(10), 356-359.
- Kishore K A, Mohan N M and Reddy G V, optimization of citric acid production using genetic algorithm, proceedings of the world congress on engineering and computer science, 2007, October 24-26, San Francisco, USA.
- Darouneh E, Alavi A, Vosonghi M, Arjmand M, Seifkordi A and Rajabi, citric acid production: Surface culture versus submerged culture, Aft. J. Microbiol. Res.2009, 3(9), 541-545.
- Kareem SO, Akpan I and Alibiowu OO, production of citric acid by Aspergillus niger using pineapple waste, Malaysian J. Microbiol.2010, 6(2), 161-165.
- Majumder L, Khalil I, Munshi M K, Alam K, Rashid H O, Begum R and Alam N, citric acid production by Aspergillus niger using molasses and pumpkin as substrates, Eur. J. Biol. Sci.2010, 2(1) , 01-08.
- Nadeem A, Syed Q, Baig S, Irfan M and Nadeem M, Enhanced production of citric Acid by Aspergillus niger M-101 using lower Alchols, Turk. J. Biochem.2010, 35(1), 7-13.
- Banik A K, Mineral nutrition of Aspergillus niger for citric acid production, Folia Microbiol.1976, 21(2), 139-143.
- Miller G L, use of dinitro salvcylic acid reagent for determination of reducing sugar. Anal. Chem.1959, 31, 426-428.
- Allen W F, Accurate and adaptable micro-kjeldhal method for nitrogen determination. Ind. Eng. Chem.1931, 3, 239-240.
- Shah A H, Hameed A and Khan G M, Improved microbial production of lysine by developing a new auxotrophic mutant of Corynebacterium glutamicum, Pak. J. Biol. Sci.2002,5(1) ,80-83.
- Marrier J R and Boulet M, Direct determination of citric acid in milk with and improved, pyridine – Acetic acid anlydride method, J. Dairy. Sci.1958, 41(1), 1683-1684.
- Kubicek C P and Rohr M, Aconitase and citric acid fermentation by Aspergillus niger , Appl. Environ. Microbiol. Nov.1985, 50(5), 1336-1338.
- Beale R N and Croft D, A sensitive method for the colorimetric determination of urea, J. Clin. Pathol.1961, 14(4), 418-424.
- Hossain M, Books J D and Maddox I S, Galactose inhibition of citric acid production from glucose by Aspergillus niger, Appl. Microbiol. Biotechnol.1985, 22(2), 98-102.
How to cite this article:
Ghosh P., Ganguly S., and Banik A.K.: Studies on Some Biochemical Changes during Citric Acid Production in a Synthetic Medium by a Mutant Aspergillus niger Ab1801.Int J Pharm Sci Res, 2012; Vol. 3(7): 2287-2290.
Article Information
60
2287-2290
595KB
1128
English
IJPSR
P. Ghosh, S. Ganguly* and A. K. Banik
Department of Chemical Engineering (Biochemical Engineering Division), University of Calcutta, 92, A. P. C. Road, Kolkata- 700 009, West Bengal, India
25 March, 2012
11 May, 2012
19 June, 2012
http://dx.doi.org/10.13040/IJPSR.0975-8232.3(7).2287-90
01 July 2012