Model MARA -Microbial Assay for Toxic Risk Assessment Toxicity Test Kit

The test consists of an array of eleven genetically diverse micro-organisms (ten bacteria and one yeast), freeze-dried in a micro-titre plate. The array is exposed to either a concentration gradient of the test sample or an undiluted sample.  Growth of the micro-organisms in the array is measured by recording the reduction of a redox dye through the use of a flat bed scanner and image analysis software.

MARA meets all the required test criteria for micro-scale ecotoxicity tests

• Simplicity
• Sensitivity
• Speed
• Accuracy
• Reproducibility
• Standardization
• Precision
• Cost effectiveness
• Convenience

In addition to the above, MARA provides the user with significantly more information which is not available from other tests

• Data for 11 test results (provided by a ‘battery of tests’ within a test)
• Minimum and maximum concentration values across the range of micro-organisms
• Can be used to produce toxic fingerprints
• Indicative of the mode of action of chemicals and toxicants
• Indicative of the similarity between chemicals and toxicants
• Can be used to produce a dendrogram comparing unknown chemicals to standards

A new addition to the MARA family is LumiMARA.  LumiMARA is a multi-species test employing an array of 11  bioluminescent bacteria consisting of 9 marine and 2 fresh water species. The LumiMARA test makes use of naturally luminescent bacteria from a variety of habitats. When these bacteria are exposed to a toxic environment their luminescence is inhibited. The level of toxicity is determined by measuring the degree of light inhibition with results in only 30 minutes.

LumiMARA is a ‘battery of tests within a test’ and can be utilised for toxicity assessment of both aquatic and terrestrial environments.

LumiMARA can provide an extremely quick picture of the toxcitity of a sample and if used as a regular testing tool can pick up any toxicity increases before they become a bigger problem.

LumiMARA results are calculated as EC50 values for each of the species. Combined integrated evaluation of all 11 species provides a mean EC50 for the entire array and can provide a unique toxic fingerprint.  

• Multi-species as well as single species test
• Indigenous bioluminescent  bacteria
• Simple protocol
• Quick  response (15-30 minutes)
• Concurrent testing of numerous samples
• Low cost