Hydrogen Sulphid Test

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1.7.3.4. Hydrogen sulphid test (MacFaddine, 1980):
Tubes of triple sugar iron agar media were inoculated by suspected culture through stabbing into the butt and the slant then covered with sterile melted paraffin wax and incubated anaerobically for 48 h at 37°C, appearance of blackening in the butt indicates H2S production.
1.7.3.5. Sugar fermentation test (Willis, 1977):
Suspected culture was inoculated to 1% peptone water tubes containing 2% bromocresol purple and 1% quantities of the following sugar: mannose, glucose, lactose, maltose, mannitol, sucrose and xylose were added. The tubes covered with sterile layer of paraffin wax and incubated anaerobically at 37°C for 7 days.
Table (A): Koneman et al. (1992) scheme
The suspected purified isolates were being identified according to the scheme recommended by Koneman et al. (1992) as shown in the following:
Biochemical tests Xylose Mannose Maltose H2S Nitrate reduction Indol Mannitol Sucrose Lactose Glucose Gelatine Spores
Species C.perfringens - + + + + - - + + + + Co C.butericum + + + - + - - + + + - Co C.tertium +/- + + - + - - + + + - To C.bifermentans - - -w + + + - - - + + C/so C.sordelli
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of trypsinized 48 hrs. supernatant of each culture were intradermally injected and the neutralized one was injected into the left side in the same manner and arrangement. The injected Guinea pigs were kept under observation for 48-72hrs. to demonstrate any dermal reaction. The results were interperitated by the degree of dermonecrotic reaction and its neutralization according to Sterne and Batty (1975) as

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