posted on 2012-12-12, 14:47authored byMahira A. Samara
Identification of various Bacteroides species studied in this thesis employed a range of morphological
biochemical and some chemotaxonomic techniques such as
short chain fatty acid analysis by gas chromatography.
Also pyrolysis gas chromatography of whole cells was
used, with special reference to the ability of this
technique in identifying bacteroides organisms involved
in an infection process.
Biochemical techniques showed the use of API 20A,
the miniaturised system of identification, to be superior
to the conventional methods for its more consistant and
rapid results. Differentiation of different species
was not possible on the basis of biochemical tests alone.
Gas liquid chromatography (GLC) of fermentation
end products of metabolism showed a varied profile ranging
from a complex pattern consisting of A,P, iB, IV, L
and S (B.asaccharolyticus and B.melaninogenicus ss.
macacae) to a simple pattern consisting of A,P,L and S
produced by the closely related B.fragilis group. A
third profile was produced by B.ruminicola ss. brevis
and B.melaninogenicus ss. melaninogenicus and consisted
of A,L and S.
Although the use of GLC has greatly improved the
taxonomy of Bacteroides speciesl Its quantitative
aspects have. not been fully explored...