the present invention provides an isolated lactic acid bacterium , lactobacillus plantarum subsp . plantarum ps128 deposited under dsmz accession no . dsm 28632 , for prophylaxis or treatment of a stress - induced disorder . the present invention further provides a composition for prophylaxis or treatment of a stress - induced disorder that comprises lactobacillus plantarum subsp . plantarum ps128 . moreover , the present invention provides a method for prophylaxis or treatment of a stress - induced disorder in a subject that comprises a step of administering an effective amount of lactobacillus plantarum subsp . plantarum ps128 to the subject .