Steroids are important biological regulators existing in hormones which are used to
control metabolism of the body. There are widespread applications in the
pharmaceutical industry. Drugs of steroid nature - anti-inflammatory and antiallergic
corticosteroids, diuretics, anabolics, androgens, gestagens, contraceptives,
antitumor medications, etc. - are now widely used in human and veterinary medicine.
Nowadays, biotechnological modifications of steroids are preferred over chemical
modifications as a green chemistry since they are more likely to be natural.
In this work four different Fusarium species were screened for bioconversion of
steroids into pharmaceutically important derivatives of steroids by reduction,
dehydrogenation, side-chain degradation etc. on A and D-rings containing many
active sites.
Fusarium spp. used in this work, namely Fusarium roseum OUT 4019, Fusarium
anguioides OUT 4017, Fusarium bulbigenum OUT 4115 and Fusarium solani OUT
4021 are filamentous fungi, which belong to the class of Deuteromyces. They can
grow using simple carbohydrates and nitrogen sources.
4-androstene-3,17-dione conversion is used as a model system. Under same
environmental conditions it is found that whole cells of Fusarium roseum OUT 4019
can dehydrogenate at C-1 and C-2 producing androsta-1,4-diene-3,17-dione and also
reduce at C-17 in addition to dehydrogenate at C-1 and C-2 producing 17-hydroxyandrosta-
1,4-dien-3-one, Fusarium anguioides OUT 4017 can reduce at C-17
producing 17-hydroxy-androst-4-en-3-one, Fusarium solani OUT 4021 can reduce at
C-3 and C-17 producing androst-4-ene-3,17-diol at 25 C° / and 160 rpm with
uncontrolled pH.
In these conversions, androsta-1,4-diene-3,17-dione, 17-hydroxy-androsta-1,4-dien-
3-one, 17-hydroxy-androst-4-en-3-one, androst-4-ene-3,17-diol were isolated with 54
%, 22 %, 26 %, 90 % yields, respectively.
In another study, bioconversion reactions of aromatic methyl ethers by Fusarium
roseum OUT 4019 were investigated and for some compounds, cleavage of methyl
ether was observed.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/3/12609258/index.pdf |
| Date | 01 February 2008 |
| Creators | Erkilic, Umut |
| Contributors | Demir, Ayhan Sitki |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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