title: Characterization of hydrocortisone biometabolites and 18S rRNA gene in Chlamydomonas reinhardtii cultures.
abstract: A unicellular microalga, Chlamydomonas reinhardtii, was isolated from rice paddy-field soil and water samples and used in the biotransformation of hydrocortisone (1). This strain has not been previously tested for steroid bioconversion. Fermentation was carried out in BG-11 medium supplemented with 0.05% substrate at 25 degrees C for 14 days of incubation. The products obtained were chromatographically purified and characterized using spectroscopic methods. 11b,17 beta-Dihydroxyandrost-4-en-3-one (2), 11 beta-hydroxyandrost-4-en-3,17-dione (3), 11 beta,17 alpha,20 beta,21-tetrahydroxypregn-4-en-3-one (4) and prednisolone (5) were the main products of the bioconversion. The observed bioreaction features were the side chain degradation of the substrate to give compounds 2 and 3 and the 20-ketone reduction and 1,2-dehydrogenation affording compounds 4 and 5, respectively. A time course study showed the accumulation of product 2 from the second day of the fermentation and of compounds 3, 4 and 5 from the third day. All the metabolites reached their maximum concentration in seven days. Microalgal 18S rRNA gene was also amplified by PCR. PCR products were sequenced to confirm their authenticity as 18S rRNA gene of microalgae. The result of PCR blasted with other sequenced microalgae in NCBI showed 100% homology to the 18S small subunit rRNA of two Chlamydomonas reinhardtii spp.
authors.affiliation: Department of Pharmacognosy and Pharmaceutical Sciences, Research Center, Faculty of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran. ghasemiy@sums.ac.ir
authors.forename: Younes
authors.initials: Y
authors.lastname: Ghasemi
authors.forename: Sara
authors.initials: S
authors.lastname: Rasoul-Amini
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Morowvat
authors.forename: Mohammad Javad
authors.initials: MJ
authors.lastname: Raee
authors.forename: Mohammad Bagher
authors.initials: MB
authors.lastname: Ghoshoon
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Nouri
authors.forename: Narges
authors.initials: N
authors.lastname: Negintaji
authors.forename: Rezvan
authors.initials: R
authors.lastname: Parvizi
authors.forename: Seyed Bagher
authors.initials: SB
authors.lastname: Mosavi-Azam
mesh_terms: D000736:Androstenes / Q000302:isolation & purification; D000818:Animals; D001711:Biotransformation; D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism*; D002845:Chromatography; D005285:Fermentation; D006854:Hydrocortisone / Q000378:metabolism*; D007700:Kinetics; D011239:Prednisolone / Q000302:isolation & purification; D011283:Pregnenes / Q000302:isolation & purification; D048030:RNA, Algal / Q000032:analysis; D012337:RNA, Ribosomal, 18S / Q000235:genetics*
chemical_list: D000736:Androstenes; D011283:Pregnenes; D048030:RNA, Algal; D012337:RNA, Ribosomal, 18S; D011239:Prednisolone; D006854:Hydrocortisone