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Microbiology

Identification Tests

Disks and strips are used in the identification and confirmation of microorganisms. They are easy to use and based on rapid screening methods like the detection of enzymes with chromogenic substrates, indicators or on complex building reactions. Also, the sensitivity to certain inhibitory substances can be used to identify organisms.

The sterility Indicator strips are used to monitor sterilization and are important for controlling the sterilization process.

 

 Strips and Discs for Differentiation

 
Cat. No.
Product Name
Pack Size
Description
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75554
Aminopeptidase Test (Gram-Positive-Test) 50 Strips For the detection of L-alanine-aminopeptidase in microoranisms with a chromogenic substrate. L-alanine aminopeptidase is an enzyme localised in the bacterial cell wall which cleaves the L-alanine from various peptides. It is found almoust only in Gram-negative microrganisms.
08382
Bacitracin Disks 50 Disks For the identification of group A b-hemolytic streptococci from other b-hemolytic streptococci. It is based on a sensitivity test and a zone inhibition greater than or equal to 14 mm indicates susceptibility to bacitracin and is presumptive of group A streptocci.
80507
Bile Esculin Disks (Esculin Bile Disks) 50 Disks Used for rapid detection of esculin hydrolysis in presence of bile for differentiatin group D streptococci fron non-group D streptococci. Group D streptococci hydrolyze the esculin to esculetin and dextrose. Esculetin reacts with an iron salt such as ferric citrate to form a blackish-brown coloured complex.
05686
DMACA Indole Disks (Indol Detection Disks) 50 Disks The DMACA Indole dics are used to determine the ability of an organism to split tryptophan into indole and a-aminopropionic acid. The presence of indole can be detected by the addition of DMACA which results in a bluish-purple complex. With this method it is possible to differentiate Escherichia coli from Klebsiella.
40405
Hippurate Disks 25 Disks Recommended to detect organisms possessing the enzyme hippurate hydrolase, which promotes the hydolysis of the peptide bond in hippurate, releasing glycine and benzoic acid as end-products. The disk method is a rapid test useful for differentiating b-hemolytic group B streptococci, Gardnerella vaginalis and Campylobacter species.
06728
Hydrogen Sulfide Test Strips (Lead Acetate Test Strips, H2S test strips)

25 Strips For the detection of hydrogen sulfide production by microorganisms from sulfur containing amino acids. Hydrogen sulfide and lead acetate react to a black precipitate. The lead acetate procedure is more sensitive than any other method for detecting hydrogen sulfide production.
04739
Indoxyl Strips (Acetoxyindole Strips) 100 Strips Test for the rapid detection of the acetate esterase activity of microorganisms. The test is based on the reaction of free indoxyl groups with oxygen, which results in a colour change. Acetate esterase activity is present e.g. in Campylobacter spp., and in Branhamella catarrhalis.
78719
Kovac's Reagent Strips (Indole Reagent Test Strips according to Kovac) 25 Strips For determination of the ability of microorganisms, primarily Enterobacteriaceae, to split indole from the tryptophan molecule.
56348
b-Lactamase Strips 100 Strips For the rapid acidimetric detection of the b-lactamase activity of microorganisms. The test is based on hydrolysis of the β-lactam ring in benzylpenicillin, which results in the production of penicilloic acid. Becauses of acidification the acidobased indicator changes the colour. Suitable for the detection of Haemophilus influenzae, Neisseria gonorrhoeae and Staphylococcus spp.
08086
Nitrate Reagent Disks 50 Disks Nitrate Reagent Disks are used to detect an organism’s ability to reduce nitrate to nitrite by nitrate reductase. This can be tested by a colorimetric reagent.
49862
Nitrocefin Disks 50 Disks For the rapid detection of b-lactamase enzymes in isolated colonies of Neisseria gonorrhoeae, Moraxella catarrhalis, Staphylococcus spp., Haemophilus influenzae and anaerobic bacteria.
49940
ONPG Disks (2-Nitrophenyl b-D-galactopyranoside Disks, b-Galactosidase Test Disks) 50 Disks Detection of b-galactosidase, an enzyme found in lactose-fermenting organisms. Lactose utilization depends upon two enzymes: b-galactoside permease, which catalyzes transport of lactose into the cell, and b-galactosidase, which breaks down lactose into galactose and glucose. ONPG (o-nitrophenyl-b-D-galactopyranose) substrate can be hydrolised by b-galactosidase and results in the release of galactose, and the yellow chromogenic compound, o-nitrophenol. ONPG, does not depend on an induced or constitutive permease enzyme to enter the cell, therefore reactions are rapid even for late lactose fermenters.
74042
Optochin Disks 50 Disks For identification/differentiation of pneumococci and viridans streptococci. Optochin (ethyl hydrocuprein hydrochloride) is inhibitory for pneumococcal growth whereas other streptococci show good growth or a very small zone of inhibition. This test is performed for the diagnosis of pneumococcal infections.
40560
70439
Oxidase Strips
Oxidase Test
100 Strips
50 Disks
Test for the detection of the cytochrome oxidase activity of microorganisms. Oxidase Test is an important differential procedure which should be performed on all gram-negative bacteria that are to be identified. In presence of the enzyme cytochrome oxidase (gram-negative bacteria) the N,N-dimethyl-p-phenylenediamine and a-naphthol react to indophenol blue.
67886
PYRase Strips (Pyrrolidonyl Peptidase Strips) 50 Strips For the rapid differentiation of Enterococci from the group D Streptococci and differentiation of Streptococcus pyogenes from other haemolytic Streptococci. It is a test for the detection of pyrrolidonyl peptidase (pyrase) presence in S. pyrogenes strains.
74146
Sterile Disks 25 Disks Can be used to test a variety of antibiotics, carbohydrates, substrates, antiseptics on bacteria in petri dishes. Soak a disk in a solution or apply some solution on the disks. Then let dry and place it in an inoculated agar plate. Each disk will absorb exactly the same amount of liquid.
75744
Tributyrin Strips (TRIBU Strips) 300 Strips Diagnostic test for the differentiation between Branhamella and Neisseria. The test principle is an enzyme hydrolysis of tributyrin.This reaction causes colour change of acidobasic indicator. The result of the reaction is read after 18-20 h.
89788
08482
77148
V Factor Disks
X+V Factor Disks
X Factor Disks
50 Disks
50 Disks
50 Disks
Member of the genus Haemophilus require hemin (X factor) and/or nicotinamid-adenin-dinucleotid (V-factor). Together with the X factor and the V factor the need for either one or both factors provides the main means of differentiation of these organisms. Haemophilus species requiring both X and V factors exhibit growth only in the vicinity of the X + V factor disks.

 

Carbohydrate Differentiation Discs

 
Cat. No. Product Name
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Pack Size Description
55876 Adonitol Discs
25 Disks
10x25 Disks
Carbohydrates Differentiation Discs are used to differentiate and identify bacteria on the basis of the ability to ferment different carbohydrates. The utilization of the carbohydrates can be detected by gas production (carbon dioxide) in liquid media and/or color change of pH indicator because of the acid production.
80372 Arabinose Discs
56481 Cellobiose Discs
56481 Cellobiose Discs
63367 Dextrose Discs
73044 Dulcitol Discs
53901 Fructose Discs
89608 Galactose Discs
89614 Inositol Discs
90058 Inulin Discs
28816 Lactose Discs
77653 Maltose Discs
94438 Mannitol Discs
94445 Mannose Discs
93196 Melibiose Discs
94226 Raffinose Discs
93999 Maltose Discs
92971 Salicin Discs
93998 Sorbitol Discs
94309 Sucrose Discs
92961 Trehalose Discs
07411 Xylose Discs

 

Sterility Indicator Strips

 
Cat. No.
Product Name
Pack Size
Description
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05290
Sterility Indicator (Radiation Sterilization) 25 Strips These indicators consist of Bacillus pumilus (ATCC 27142) spores impregnated on paper strips. The spores are highly resistant to radiation and are used to monitor efficiency of radiation sterilization. These indicators as specified by U.S. military specification MIL-S-36586 are GMP requirements of U.S. FDA.
74041
Sterility Indicator (Steam Sterilization) 25 Strips These indicators consist of Bacillus stearothermophilus (ATCC 7953) spores impregnated on paper strips. The spores are highly resistant to heat and are used to monitor autoclave performance. These indicators as specified by U.S. military specification MIL-S-36586 are GMP requirements of U.S. FDA.