Identification of a new probiotic Lactobacillus alimentarius W369 from Chinese traditional pickles

Abstract:

[Objective] A new lactic acid bacterium was isolated from Chinese traditional pickles and its potential probiotic properties were analyzed. [Methods] The strain was identified by morphological observation, physiological and biochemical tests and 16S rRNA gene comparison. Its probiotic properties were evaluated, including resistance to NaCl, the minimum inhibitory concentration of antibiotics, nitrite degradation ability and cholesterol removal ability. [Results] This strain was identified as Lactobacillus alimentarius W369 (No. CGMCC 7.180). L. alimentarius W369 could survive under the concentration of 10% NaCl and it was sensitive to some common antibiotics. By studying its probiotic properties, we found that its nitrite degradation rate reached 92.92% after 72 h and the cholesterol removal rate reached 31.80%. The fermented supernatant showed strong abilities of DPPH· and the superoxide anion radical scavenging capacity, as well as Fe2+ chelating ability. The clearance rate were (88.02±1.48)%, (43.75±3.10)% and (29.99±2.34)% respectively. Strain W369 also exhibited strong reducing capacity, hydroxyl radical scavenging action and lipid peroxidation inhibition capacity. Both the fermented supernatant and cell-free extracts exhibited glutathione peroxidase (GSH-Px) and superoxide dismutase (Mn-SOD) activities. [Conclusion] L. alimentariusW369 possessed many probiotic properties including nitrite degradation ability, cholesterol removal ability and antioxidant activity. It has many potential application values.

Key words:Lactobacillus alimentarius W369;nitrite degradation;cholesterol removal;antioxidant activity