JOURNAL OF CULTURE
COLLECTIONS
Volume 5, 2006-2007, pp. 64-72
BACTERIOCIN-LIKE
ACTIVITY FROM WEISSELLA CONFUSA
AND PEDIOCOCCUS ACIDILACTICI ISOLATED FROM
TRADITIONAL
THAI FERMENTED SAUSAGES
Veerapon
Chavasirikunton1, Savitri Vatanyoopaisarn2 and
Chantaraporn
Phalakornkule1*
1Department
of Chemical Engineering, Faculty of Engineering;
2Department of Agro-Industrial Technology, Faculty of Applied
Science, King Mongkut’s Institute of Technology,
North
Bangkok, 1518 Pibulsongkram road,
*Corresponding
author, e-mail: cpk@kmitnb.ac.th
Summary
Bacteriocin-like activity (BLA)
was screened in 133 strains of lactic acid bacteria (LAB) isolated from
traditional Thai fermented sausages. The inhibition assay against the test
organisms showed that eight out of 133 isolates (CP1-15, CP2-11, CP3-1, CP7-3,
CP10-3, CP11-6, CP14-1 and CP14-4) suppressed the growth of Bacillus cereus and four (CP1-15,
CP7-3, CP14-2 and CP14-3) suppressed the growth of Staphylococcus aureus but none could suppress the growth of Escherichia coli and Salmonella sp. The isolates with the
highest activity against the two Gram positive test strains (CP3-1 for B. cereus and CP7-3 for S. aureus) were further investigated
for the effect of heat treatment at different pH values and for combined
effects of dual mixtures. The increase in heating temperature (between 65 and
100 oC) and time (between 5 and 60 min) significantly decreased
BLA, while the changes in pH (between 4 and 6) had little effect. When the
filtrates of the two isolates were mixed, BLA seemed to be synergistic against
each test strain. Regression equations were obtained by fitting the
experimental percent inhibition data with second-order polynomial equations.
The simulated data agreed well with the experimental data within 10 % when
the filtrates were incubated at 65 oC for 5, 15, 30 and 60 min
and at 80 oC for 5, 15 and 30 min. The isolates CP3-1 and
CP7-3, which had an antagonistic effect against the two strains of Gram
positive foodborne bacteria, were formerly identified as Weissella confusa and Pediococcus acidilactici,
respectively. It is the researcher’s belief that this is the first report on
BLA from W. confusa against B. cereus.
Key
words: lactic acid bacteria,
bacteriocin, antibacterial activity, inhibitory activity, Weissella confusa, Pediococcus acidilactici