Use of aqueous two-phase systems in sample preparation for polymerase chain reaction-based detection of microorganisms

• An aqueous two-phase system, consisting of poly(ethylene glycol) (PEG) and dextran, was employed to separate polymerase chain reaction (PCR)-inhibitory substances from bacterial cells. The PCR inhibition of four soft cheeses was examined and three of them were found to be strongly PCR-inhibitory. Extraction of the PCR-inhibitory soft cheeses inoculated with Listeria monocytogenes in an aqueous two-phase system containing 8% (w/w) PEG 4000 and 8% (w/w) dextran 500, was found to lower the PCR detection level of L. monocytogenes by more than four orders of magnitude in two of the cheeses compared to the case where no such sample pretreatment was performed. Depending on the type of cheese used, the PCR-inhibitory factors were found to be enriched in either the top or bottom phase in the aqueous two-phase system. These results show that different soft cheeses contain different types and amounts of PCR-inhibitory substances.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Industriell bioteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Industrial Biotechnology (hsv//eng)

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Nyckelord

PCR-inhibitory factors

Sample preparation method

aqueous

Two-phase systems

Cheese

Polymerase chain reaction

Microorganisms

Aqueous two-phase systems

Listeria monocytogenes

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)