Biopreservation of Vegetable Foods - Food Biopreservation - page 100

geneous and faster fermentations in newly-operating plants that still lack the appro-
priate resident LAB microbiota. L. plantarum is also the main bacterial species in
other traditional vegetable fermentations such as capers and Almagro eggplants
(Seseña et al. 2004 ; Pérez Pulido et al. 2005 ). Therefore, plantaricin-producing strains
could also fi nd applications in these (and probably others) fermented vegetables.
Cereals and fermented doughs can also be a good source of LAB strains produc-
ers of bacteriocins and bacteriocin-like substances, such as bavaricin A, plantaricin
ST31, BLIS C57, amylovorin L and others (Messens et al. 2002 ; Messens and De
Vuyst 2002 ; Narbutaite et al. 2007 ; Settanni and Corsetti 2008 ) as well as antifungal
compounds (Valerio et al. 2009 ; Dalié et al. 2010 ). Although amylovorin is not
active against Bacillus , amylovorin production may serve to enhance the competi-
tiveness of the producer strain against other lactobacilli in the fermentation (Messens
et al. 2002). After a more direct screening for LAB producing bacteriocin-like anti-
rope activities, two strains were selected ( L. plantarum E5 and Ln. mesenteroides
A27) that inhibited ropiness in the bread for more than 15 days (Pepe et al. 2003 ).
According to another study, production of antimicrobial activity by sourdough LAB
appears to occur at a low frequency, but the producer strains are active in producing
antimicrobial activity under sourdough and bread-making conditions (Corsetti et al.
2004 ). One L. lactis strain isolated from raw barley showed a wider inhibitory spec-
trum than sourdough LAB (Settanni et al. 2005 ). This strain was found to produce
lacticin 3147, and was shown to produce bacteriocin in situ without interfering with
growth of bacteriocin-insensitive Lactobacillus sanfranciscensis strains.
Furthermore, the production of antimicrobial substances, such as reutericyclin and
bacteriocins may enhance the competitiveness of strains in fermented doughs
(Gänzle and Vogel 2003 ; Leroy et al. 2007 ), being considered a desirable trait for
starter culture development (Corsetti and Settanni 2007 ; De Vuyst et al. 2009 ). It has
been suggested that sourdoughs or cultured broths fermented with bacteriocin-pro-
ducing lactobacilli could be applied to inhibit rope formation by bacilli in yeast-
leavened breads (Mente

et al. 2007 ; Settanni and Corsetti 2008 ; Valerio et al. 2008 ).
Ethnic fermented vegetable foods are good candidates for isolation of antagonis-
tic strains producers of (maybe) new bacteriocins, specifi cally adapted to the par-
ticular fermentation conditions of these foods (Kostinek et al. 2007 ; Yoon et al.
2008 ; Ge et al. 2009 ; Hata et al. 2009 ; Huang et al. 2009 ; Tamang et al. 2009 ; Gao
et al. 2010 ). In one study, the nisin-producer L. lactis subsp. lactis IFO12007 iso-
lated from miso was used as starter for fermentation of cooked rice and rice koji
supplemented with soybean extract (Kato et al. 2001 ). The producer strain prolifer-
ated in the cooked rice and produced enough nisin activity to inhibit B. subtilis with-
out causing any adverse effect on growth of Aspergillus oryzae during the koji
fermentation. Furthermore, a lower salt content could be added to rice miso without
compromising the lactic acid fermentation of both rice and soybeans (Kato et al. 2001 ).
Fermented millet fl ours are widely consumed in many African countries. Yet, the
number of studies carried out on their LAB microbiota and their bacteriocins are
limited (Ben Omar et al. 2006 , 2008 ). However, results indicate that LAB strains
from these fermented foods may have strong inhibitory activities against foodborne
pathogens. In one study, the plantaricin-producing strain L. plantarum 2.9 (isolated

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