Following the morphological studies of bacterial colonies and cells, the biochemical properties of unknown bacteria were explored through their growth and colony color on two selective and differential media, MacConkey agar and mannitol salt agar, and the results of the oxidase test
. MacConkey agar contains bile salts and crystal violet, which inhibit the growth of Gram-positive bacteria.
Further, characterization of the bacterial strain was performed based on oxidase test
, hanging drop technique, mannitol fermentation test, nitrate reduction test, TSI test and methyl red test (Qazilbash, 2002).
The isolates were identified using the standard biochemical reactions (TSI, urease test, citrate test, MIO, LIA and oxidase tests
) as 94 (70%) Enterobacteriaceae species, 25 (17%) Acinetobacter spp.
Biochemical characterization of isolates Oxidase test
Then oxidase test
were done, for suspicious colonies utilaztion of sugars (glucose, lactose, maltose and sucrose) were used.
Specific biochemical tests such as gelatin liquefaction, production of levan, catalase test, oxidase test
, arginine hydrolysis, indole production, phosphorous solubilization and growth at 4 and 41[degrees]C were conducted for identification of P.
All the seven isolates were positive for oxidase test
. In urease test only strain ISD7 was found positive, all other strains ISD1, ISD2, ISD3, ISD4, ISD5 and ISD6 were found negative.
Characteristic of other Bacterial isolates from Amirthi forest Biochemical VITNJ1 VITNJ2 VITNJ3 VITNJ4 VITNJ5 Properties Gram Staining + + + + + Shape Rod Rod Rod Rod Rod Indole test - - - - - Methyl red test - - + + - Voges Proskauer + + + + - Citrate Utilization + + + + + Oxidase test
- - + + - Catalase Test - - + + + Urease - - - - - Biochemical VITNJ6 VITNJ7 VITNJ8 VITNJ9 Properties Gram Staining + + - + Shape Rod Rods Rods Rods Indole test - + - - Methyl red test - - - + Voges Proskauer - - + + Citrate Utilization - - + - Oxidase test
- - - + Catalase Test + + + + Urease - - - - Table 3.
On the basis of growth on McConkey agar media, oxidase test
and oxidative-fermentative glucose tests the strains were grouped according to Weaver-Hollis scheme.
perfringens type D was confirmed through different biochemical tests (IMViC, Sugar fermentation, Catalase reaction, Oxidase tests
, Gelatin hydrolysis, Litmus milk reaction and Lecithinase) and PCR.
gram staining, motility, capsule, IMViC, cataalse, oxidase tests
as per methods described by Barrow and Felthem (1993).
GPC were identified by catalase, coagulase, and modified oxidase tests
. Gram negative bacilli (GNB) were identified by Motility, Oxidase, Catalase, IMViC, Urease, Triple Sugar Iron agar, Nitrate reduction.