Colorex™ MRSA is a chromogenic medium for the selective isolation of Methicillin-Resistant Staphylococcus aureus (MRSA). The medium can be used for the routine screening of clinical specimens for MRSA from a variety of sampling sites such as the nose, throat and groin. The medium incorporates a nutritious peptone base medium and a number of selective agents to inhibit most Gram-negative and Gram-positive bacteria as well as yeasts and moulds. The chromogenic detection of specific enzyme activity leads to the formation of pink/mauve colonies indicating MRSA (including low level resistant and hetero-resistant strains) following incubation at 37°C for 18-24 hours. Other organisms, if present are indicated by blue or colourless colonies. Any presumptive isolates must be confirmed using serological and/or biochemical techniques available to the laboratory. The use of this chromogenic medium does not diminish the requirement for conventional antimicrobial susceptibility tests for the confirmation of methicillin resistance.

Limitations:

1. S.aureus strains that possess a low MIC to the selective agent present in the medium but are mec A negative may form colonies on the medium.

2. Some MRSA strains may form typical colonies surrounded by a matte halo. The formation of the halo serves no diagnostic function.

3. Certain methicillin-resistant coagulase-negative staphylococci (CNS) may produce characteristic colonies. In some cases differentiation may be achieved by examination of the colour of these colonies, as they may be considerably darker in colour (bluish purple to a very dark pink/magenta).

4. Certain bacterial species other than staphylococci may produce colonies with a characteristic colour.

Lysed horse blood is used for special purposes in culture media. It has been used for many years in Corynebacterium diphtheriae media, where better growth was observed after lysis of the horse blood by the tellurite in the medium. It is also documented that lysed blood stimulates the growth of Haemophilus influenzae due to the release of Nicotinamide Adenine Dinucleotide in the horse blood from the ruptured erythrocytes. In antibiotic susceptibility testing, lysed horse blood is added to the medium to improve the reactions with trimethoprim and sulphonamides. Most culture media, unless specially processed for susceptibility testing, contain amounts of thymidine which can antagonise the inhibitory effects of these antimicrobials. When horse blood is lysed the erythrocytes release an enzyme thymidine phosphorylase which converts thymidine into the much less antagonistic compound thymine.

Recent developments in culture media have given rise to the use of chromogenic substrates as a means of differentiating bacteria

particularly among the coliform group of organisms. This is one such medium and has been developed as a selective medium for the isolation and enumeration of Escherichia coli without the need for membranes or pre-incubation. Based on the formulation of Tryptone Bile Agar it incorporates a chromogenic substrate, X-Glucuronide, to detect the ß-glucuronidase enzyme which is specific for the majority of E. coli strains. Approximately, 3-4% of E. coli are glucuronidase negative including E. coli O157.(1) The advantage of the chromogenic substrate is that the reaction is concentrated within the colony resulting in distinctive blue/green colonies of E. coli while the other coliforms produce cream colonies.

The tryptone provides the required carbon, nitrogen and vitamins. Bile salts No.3 is a selective agent against Gram-positive bacteria. X-glucuronide is a chromogenic substrate. Agar is solidifying agent.

Liên hệ mua hàng:

Công ty Labcare Việt Nam – chuyên cung cấp, phân phối Môi trường nuôi cấy vi sinh, test sinh hóa, kháng huyết thanh, hóa chất, dụng cụ, thiết bị, vật tư tiêu hao.

Hotline: 0938976508

Email: info@labcare.vn

Website: labcare.vn

CompactDry™ is a ready-to-use dehydrated culture media system that reduces the time needed to perform everyday microbial testing on food, cannabis, meat, cosmetics, raw materials, and more. Simply add 1ml of the prepared sample to the center of the plate. The sample will self-defuse and rehydrate media fully on its own. No stamping or spreading is needed.

CompactDry™TCR is a method recommended for the determination of total aerobic bacterial counts. Plates are AOAC PTM 082201 validated and is measurable after only 24 hours of incubation.

The benefits are easy to spot:

Each sleeve contains 4 connected plates that can be easily separated to support a variety of dilution scenarios.

• Rapid results in just 24 hours.
• Dye indicator gives enumerated results
• CompactDry™ is room temperature stable. Competitive products require refrigerated storage.
• Rigid plate design is easy to label, manipulate, and stack.
• Self-diffusing media does not require stamping or spreading.
• Plate headspace allows for three-dimensional colony growth and colony picking for subculture and ID.
• Plate design assures sample containment and eliminates possible sample leakage seen with other film-based products.
• All colonies are easy to read from center to rim.
• Long shelf-life, room temperature storage.

Liên hệ mua hàng:

Công ty Labcare Việt Nam – chuyên cung cấp, phân phối Môi trường nuôi cấy vi sinh, test sinh hóa, kháng huyết thanh, hóa chất, dụng cụ, thiết bị, vật tư tiêu hao.

Hotline: 0938976508

Email: info@labcare.vn

Website: labcare.vn

Alicyclobacillus acidoterrestris is a gram-positive, spore-forming bacillus that occurs widely in nature. This specie has been studied substantially after the incident of turbidity of transparent apple juice in 1984. The Alicyclobacillus genus bacteria, which peculiarly grows under relatively high temperatures and acid conditions, is called Thermo-acidophilic Bacilli (TAB) [1, 2, 3].

TAB are not destroyed by pasteurization and may remain in final products of fabricated food and beverages. TAB are not known to be harmful to health but are known to degrade the quality of juices and other products by producing guaiacol, causing off-flavor. Even without the off-flavor problem, product values may be degraded by slight deterioration during distribution.

It is very difficult to avoid contamination of TAB, which are common in soil. Fortunately, A. acidocaldarius and other main species that cause contamination are known to be harmless, and damage caused by TAB can be minimized by monitoring the contamination of A. acidoterrestris, which is known to be harmful. These species, however, cannot be detected by usual isolation culture methods as they grow only under acidic and relatively high temperature conditions.

Because of frequent occurrence of fruit juice deterioration incidents in Europe and other regions, Japan Fruit Juice Association developed and publicized a unified test method for TAB in March 2003 [4]. To allow easy performance of this test, we developed a kit that differentiates A. acidoterrestris in terms of productivity of guaiacol, which causes off-flavor.