Lactose-Free Fermented Milk Production Using Lactococcus lactis NK24 and NK34 with Immune-Enhancing Effects on RAW...

Area of Science:

• Food Science
• Immunology
• Microbiology

Background:

• Lactose intolerance affects a significant portion of the global population.
• Probiotics, such as Lactococcus lactis strains, are known for their health benefits.
• Fermented dairy products are a common vehicle for probiotic delivery.

Purpose of the Study:

• To develop lactose-free fermented milk using specific Lactococcus lactis strains.
• To evaluate the immune-enhancing properties of the produced lactose-free fermented milk.

Main Methods:

• Lactose-free milk was fermented using Laticaseibacillus rhamnosus GG (LGG), Lactococcus lactis NK24, and Lactococcus lactis NK34.
• Physicochemical properties and bacterial counts were monitored over 28 days.
• Immune cell responses (NO production, phagocytosis, cytokine expression) were assessed in vitro using RAW 264.7 cells.

Main Results:

• The fermented milk samples demonstrated immune-stimulating effects on RAW 264.7 cells, including increased nitric oxide (NO) production and phagocytic activity.
• mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines were elevated.
• Protein expression of iNOS, COX-2, and phosphorylation of key signaling molecules (p38, p65, JNK, ERK) were promoted.

Conclusions:

• Lactose-free fermented milk produced by Lactococcus lactis NK24 and Lactococcus lactis NK34 effectively enhances immune responses.
• Immune enhancement is mediated through the activation of nuclear factor-kB (NF-kB) and mitogen-activated protein kinase (MAPK) pathways.
• These findings suggest potential for developing this fermented milk as a functional food for immune support.