+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Acid adaptation of Listeria monocytogenes strains does not offer cross-protection against an activated lactoperoxidase system



Acid adaptation of Listeria monocytogenes strains does not offer cross-protection against an activated lactoperoxidase system



Journal of Food Protection 62(6): 670-673



Listeria monocytogenes has been implicated in foodborne illness outbreaks involving several types of cheeses made from acidified milk. Acid shock response (ASR) and acid tolerance response (ATR) could be possible reasons for its survival. The ASR and ATR of three strains of L. monocytogenes (V7, V37, and CA) in skim milk acidified to pH 4.0 and 3.5 with lactic acid and held at 32 degrees C were studied. Studies were also done to determine if acid adaptation of the organism enhanced survival in the presence of an activated lactoperoxidase system. The cells were directly shocked at pH 4.0 and 3.5 in skim milk to study the ASR. To study the ATR, cells were initially adapted in skim milk at a mild pH of 5.5 for the equivalent of one generation before being shocked at pH 4.0 and 3.5 in skim milk. Cells adapted at pH 5.5 in tryptic soy broth without dextrose and nonadapted cells were challenged at pH 4.5 in skim milk with or without an activated lactoperoxidase system. In all cases, viability and pH were measured 24 or 48 h after challenge. In pH 4.0 skim milk, for all three strains, the adapted cell population survived better (0.5 to 1.0 log higher) than that of nonadapted cells for 24 h. In pH 3.5 skim milk, the acid-adapted populations of all three strains were 3 to 4 logs greater than those of nonadapted cells at 6 h. The acid adapted cells of all three strains had survival rates similar to those of the nonadapted cells at pH 4.5 both in the presence and absence of an activated lactoperoxidase system. It was also evident that these strains do not exhibit an adaptive ATR at pH 4.5, although they do at lower pH levels (pH 4.0 and 3.5). Survival due to the ATR was better seen at pH 3.5 than at pH 4.0.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 003030664

Download citation: RISBibTeXText

PMID: 10382659


Related references

Acid Adaptation of Listeria monocytogenes Strains Does Not Offer Cross-Protection against an Activated Lactoperoxidase System. Journal of Food Protection 62(6): 670-673, 1999

Protein profile changes in acid adapted Listeria monocytogenes exhibiting cross-protection against an activated lactoperoxidase system in tryptic soy broth. Journal of food safety 20(1): 27-42, 2000

Stability of sublethal acid stress adaptation and induced cross protection against lauric arginate in Listeria monocytogenes. International Journal of Food Microbiology 203: 49-54, 2015

A note on the inhibition of Listeria monocytogenes NCTC 11994 in milk by an activated lactoperoxidase system. Letters in Applied Microbiology 8(6): 203-205, 1989

Combined effect of bacteriocin-producing lactic acid bacteria and lactoperoxidase system activation on Listeria monocytogenes in refrigerated raw milk. Journal of Applied Microbiology 83(3): 389-395, 1997

Effect of acid adaptation on the fate of Listeria monocytogenes in THP-1 human macrophages activated by gamma interferon. Infection and Immunity 70(8): 4369-4378, 2002

Antibacterial activity of the lactoperoxidase system on Listeria monocytogenes. Microbiologie, Aliments, Nutrition 7(1): 25-30, 1989

Goats' Milk Lactoperoxidase System Against Listeria monocytogenes. Journal of Food Protection 56(11): 988-990, 1993

Bile stress response in Listeria monocytogenes LO28: adaptation, cross-protection, and identification of genetic loci involved in bile resistance. Applied and Environmental Microbiology 68(12): 6005-6012, 2002

Effect of the lactoperoxidase system on Listeria monocytogenes behavior in raw milk at refrigeration temperatures. Applied and Environmental Microbiology 57(11): 3355-3360, 1991

Inhibition of Listeria monocytogenes by the lactoperoxidase-thiocyanate-hydrogen peroxide antibacterial system. Abstracts of the Annual Meeting of the American Society for Microbiology 87: 278, 1987

Enhanced thermal destruction of Listeria monocytogenes and Staphylococcus aureus by the lactoperoxidase system. Applied and Environmental Microbiology 56(9): 2711-2716, 1990

Antibacterial Activity of the Lactoperoxidase System Against Listeria monocytogenes and Staphylococcus aureus in Milk. Journal of Food Protection 53(12): 1010-1014, 1990

Synergistic effect of nisin and the lactoperoxidase system on Listeria monocytogenes in skim milk. International journal of food microbiology 40(1-2): 35-42, 1998

Inhibition of Listeria monocytogenes growth by the lactoperoxidase-thiocyanate-H2O2 antimicrobial system. Applied and Environmental Microbiology 55(11): 2802-2805, 1989