All GI symptoms were significantly improved over time by Perilla frutescens extract during the intervention phase ( bloating : -0.440.56 , p = 0.0003 ; passage of gas : -0.300.66 , p = 0.0264 ; GI rumbling : -0.550.87 , p = 0.0014 ; feeling of fullness : -0.360.72 , p = 0.0152 ; abdominal discomfort : -0.540.75 , p = 0.004 ) , whereas in the placebo group only abdominal discomfort was significantly improved ( -0.310.55 , p = 0.0345 ) .