Rapid monitoring of bacterial growth and metabolism with the PMEU Unit from clinical, environmental, food and process industry samples

THE PRESENTATION OF PMEU TECHNOLOGY AT THE NEW ZEALAND MICROBIOLOGICAL SOCIETY MEETING 2ND OF DECEMBER 2010, AUCKLAND, WITH THE MOTTO “small things, BIG ideas” BY ADJUNCT PROFESSOR ELIAS HAKALEHTO

ABSTRACT


The idea of constructing a cultivator where microbe enrichment could be started on the sampling site has fascinated us for many years. In the PMEU (Portable Microbe Enrichment Unit) one actually intensifies the research on metabolic reactions in a multiplied scale. This equipment also simulates the interactions between different microbes, and it therefore can be used for studying microbial ecosystems.

Sampling in an Austrian hospital during three years from the bile specimens of about 250 patients indicated that coliformic bacteria and fecal enterococci represented around 60% of the microflora in this part of the gastrointestinal tract. The mixed acid fermenting coliformic strains and the neutral end-products producing Klebsiella/Enterobacter group were shown to live in symbiosis in the PMEU cultures implying to their cooperation in the duodenum. This gives an idea how the microbial community maintains intestinal conditions by regulating the pH and other parameters.

The PMEU Spectrion® equipment validated by the State Research Centre of Finland (VTT) has Ethernet connections which make it possible to follow up the microbe enrichment and detection process in real time. The water department field trials are reported. The PMEU can be used to monitor directly both hygiene indicator strains as well as pathogenic bacteria, both in water and in food. A recent report involving the National Institute of Health and Welfare in Finland describes detection of Campylobacter sp. from natural and household waters using the combination of PMEU enrichment and the real time PCR.

In hospital tests at Kuopio University Hospital in Finland, the PMEU Scentrion® gas sensing bacterial cultivator has been validated for the microbiological blood testing of neonatal and cancer patients. The PMEU has also been used for monitoring the development of the microflora after the birth or antibiosis. The enhanced enrichment could be used effectively for improving the recovery of bacterial cells in the detection process.

Hygiene Monitoring with the Portable Microbe Enrichment Unit (PMEU)

Elias Hakalehto, Doc., Ph.D.
Department of Biosciences
University of Eastern Finland
P.O.B. 1627
FI-70211 Kuopio
Finland

Abstract, 41st R3-Symposium of the R3-Nordic Society in Espoo 25.-26.5.2010

The PMEU (Portable Microbe Enrichment Unit) technology (Samplion Oy, Siilinjärvi, Finland) is a microbe cultivation method producing advantageous growth conditions for individual bacterial cells. Therefore, monitoring of bacterial populations and the presence of potential contaminants is optimised in terms of speed and accuracy. Hygienically important isolates of various bacterial strains have been cultivated aerobically, microaerobically or anaerobically using standard broth media by standard PMEU enhanced enrichment technology, or by PMEU Spectrion ® or PMEU Scentrion ® sensored units equipped with optical, IR, or gas sensors. The units were produced by Samplion Oy according to the ISO 9001 accepted protocol. The reference cultivations were carried out using standard microbiological procedures. The PMEU Spectrion ® is being validated by the VTT of Finland. PMEU versions facilitated ultra-fast detection of coliformic bacteria, bacilli, salmonellas, staphylococci, streptococci, campylobacteria and other groups. The PMEU Scentrion ® equipped with gas sensors for volatile organic compounds detected the contaminants at concentrations of bacterial levels around 10-1000 cfu/ml in 2-5 hours. Also the hospital validation studies in Austria and Finland are summarized. Moreover, The PMEU has been demonstrated to help the environmentally stressed cells to recover and become viable in the enrichment cultures. Hygiene sampling was carried out using a specific sampling syringe serving also as an incubator in the PMEU.

Enhanced enrichment and detection of thermotolerant Campylobacter species from water using the Portable Microbe Enrichment Unit and real-time PCR

Tarja Pitkänen, Juliane Bräcker, Ilkka T. Miettinen, Anneli Heitto, Jouni Pesola, and Elias Hakalehto

Can. J. Microbiol. 55(7): 849–858 (2009):

Abstract: An enhanced enrichment using the Portable Microbe Enrichment Unit (PMEU) with the microaerobic bubbling of broths was applied for the detection of thermotolerant Campylobacter species from water. This PMEU enrichment was compared with the conventional static enrichment of the international standard ISO 17995:2005. In addition, Campylobacter detection after enrichment using a real-time PCR detection was compared with colony counts. The tests with stressed Campylobacter jejuni cells in drinking water indicated that the PMEU enrichment yielded a significantly higher number of Campylobacter cells in the Bolton broth compared with the conventional static incubation. Application of the real-time PCR technique shortened the Campylobacter detection time. This combination of method modifications can be used for Campylobacter detection from water and adds methodological repertoire for the rapid survey and management of waterborne outbreaks.

Key words: Campylobacter, enrichment, Portable Microbe Enrichment Unit, real-time PCR, water.