Aims: Isolation of bacteriocinogenic lactic acid bacteria (LAB) from the Malaysian mouldfermented product tempeh and characterization of the produced bacteriocin(s). Methods and Results: LAB were present in high numbers in ®nal products as well as during processing. Isolates, Enterococcus faecium B1 and E. faecium B2 (E. faecium LMG 19827 and E. faecium LMG 19828, respectively) inhibited Gram-positive indicators, including Listeria monocytogenes. Partially puri®ed bacteriocins showed a proteinaceous nature. Activity was stable after heat-treatment except at alkaline pH values. Both strains displayed a bacteriostatic mode of action. Bacteriocin production was associated with late exponential/early stationary growth. Molecular mass, calculated by SDS-PAGE, was 3á4 kDa for B1 bacteriocin, and 3á4 kDa and 5á8 kDa for B2 bacteriocins. PCR screening of enterocin-coding genes revealed three ampli®ed fragments in total genomic DNA that may correspond with PCR signals for enterocin P, enterocin L50A and enterocin L50B. Both B1 and B2 contained a 42-kb plasmid. No differences in bacteriocinogenic capacity were found between wild type strains and plasmidcured strains. Conclusions: It was possible to isolate bacteriocinogenic E. faecium active against various Gram-positive bacteria from ®nal products of tempeh. Signi®cance and Impact of the Study: A ®rst step in applying biopreservation to fermented South-east Asian foods is to obtain bacteriocinogenic LAB from this source. Such isolates may also be used for biopreservation of mould-fermented foods in general, including various types of mould-ripened cheese.

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