The present invention provides an isolated lactic acid bacterium, Lactobacillus plantarum subsp. plantarum PS128 deposited under DSMZ Accession No. DSM 28632. The present invention further provides a composition that comprises Lactobacillus plantarum subsp, plantarum PS128 and a carrier. 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. The present invention also provides a method for prophylaxis or treatment of a functional gastrointestinal disorder in a subject that comprises a step of administering an effective amount of Lactobacillus plantarum subsp. plantarum PS128 to the subject.
