Abstract: The present disclosure is related to a method for improving mitochondria in a cell, comprising step of treating the cell with an extraction of Emblica officinalis, for improving ability of mitochondria to perform oxidative phosphorylation and synthesize adenosine triphosphate. The present disclosure is also related to a method for promoting proliferation of a stem cell, comprising step of treating the stem cell with an extraction of Emblica officinalis, for improving division rate of the stem cell.