• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.111-114
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• 2000

Streptomyces are widespread in nature and play a very important role in the biosynthesis as well as biodegradation of natural and unnatural aromatic compounds. Both qualitatively and quantitatively through TLC and UV spectrophotometric assays, it was observed that the thermophilic soil bacteria S. setonii (ATCC 39116), which can utilize a benzoate as a sole carbon and energy source in a minimal liquid culture, was not very sensitive to the benzoate concentation and to the culture conditions such as the pH and temperature. The in vitro conversion of a catechol to a cis, cis-muconic acid by a crude S. setonii lysate implies that the aromatic ring cleavage by S. setonii is initiated by a thermostable catechol-1,2-dioxygenase, the key enzyme in the ortho-cleavage pathway of aromatic compound biodegradation. Unlike non-degrading S. lividans, S.setonii was also highly resistant to other similar hazardous aromatic compounds, exhibiting almost no adverse effect on its growth in a complex liquid culture.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.89-96
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• 1994

The ether-type chitin derivatives were synthesized by reacting chitin with chloropropane, propylene oxide and chloropropane diol to form propyl chitin(PPC), hydroxypropyl chitin(HPC) and dihydroxypropyl chitin(DHPC). These derivatives formed a lyotropic cholesteric liquid crystallinity in concentrations over 30 wt% solution in formic acid (99%). Cast films from liquid crystalline solutions were degraded by lysozyme in pseudo-extra cellular tluid(PECF)solutions, at pH 1.2, pH 6.7 and pH 8.2. Three ether-type chitin derivatives rapidly degraded within the first week, and showed a decreased mechanical strength in neutral pH range. Dihydroxypropyl chitin showed the best biodegradation among these derivatives.