• Prachi Patil School of Pharmacy, Devi Ahilya University, Indore.
  • Rajesh Sharma Devi Ahilya University, Ring Road, Indore-452001
  • Tushar Banerjee Devi Ahilya University, Indore-452001
  • Shridhar Patil Devi Ahilya University, Indore-452001


Objective: Permeability of hydrophobic steroid substrates across cell membrane is a critical factor during microbial bioconversion. To increase substrate intake, the feasibility of some organic solvents and emulsifiers as substrate carrier on the bioconversion of 6-methylene androstenedione to exemestane was assessed.

Methods: Androstenedione, a commonly available steroid precursor, was chemically converted 6-methylene androstenedione. The time course of exemestane accumulation was estimated after addition of 6-methylene androstenedione dissolved in some organic solvents or dispersed with emulsifiers by growing and immobilized cells of Arthrobacter simplex NCIM 2449 in shake flask cultures.  

Results: The use of substrate carriers for addition of 6-methylene androstenedione enhanced the bioconversion several folds. With growing bacterium in triplicate flasks, a peak mol % bioconversion recorded was- ethanol (67.25, 72 h); soybean oil + tween 80 (50.37, 48 h); acetone (38.84, 48 h); soybean oil (38.36, 48 h); lecithin (32.73, 48 h), methanol (32.71, 48 h) and tween 80 (10.37, 48 h). As compared to the growing cells, the bioconversion with Ca-alginate immobilized cells was delayed and peak mol % bioconversion was recorded as ethanol (60.78, 120 h); soybean oil + tween 80 (42.98, 120 h);  methanol (40.50,  72 h);  soybean oil (38.36, 48 h);  acetone (31.18, 72h ) and lecithin (33.67, 120 h); tween 80 (13.87, 120 h).

Conclusion: The use of substrate carriers for addition of 6-methylene androstenedione increased the permeability of substrate and may be used to increase the yield of exemestane and reduce incubation time.

Author Biographies

Prachi Patil, School of Pharmacy, Devi Ahilya University, Indore.
Research Scholar, School of Pharmacy, Devi Ahilya University, Indore
Rajesh Sharma, Devi Ahilya University, Ring Road, Indore-452001
Professor & Head, School of Pharmacy,
Tushar Banerjee, Devi Ahilya University, Indore-452001

Assistant Professor, School of Life Sciences

Shridhar Patil, Devi Ahilya University, Indore-452001

Emeritus fellow (UGC), School of Life Sciences.


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How to Cite
Patil, P., R. Sharma, T. Banerjee, and S. Patil. “SUBSTRATE CARRIERS FOR C-1(2)-DEHYDROGENATION OF 6-METHYLENE ANDROSTENEDIONE TO EXEMESTANE BY GROWING AND IMMOBILIZED ARTHROBACTER SIMPLEX NCIM 2449”. Asian Journal of Pharmaceutical and Clinical Research, Vol. 10, no. 2, Feb. 2017, pp. 392-6, doi:10.22159/ajpcr.2017.v10i2.15861.
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