Preliminary Qualitative Analysis, Total Phenolic, Flavonoid Contents, and Antioxidant Activities of Ethanolic Extract of Young and Mature Stems of Piper chaba Hunter: A Comparative Study. Author: Md. Shihab Uddin Sohag,Quazi Istiaque Bari, Abida Sultana, Md. Boniamin, Md. Saju Ahmad, Sanjay Dutta, Fazle Rabbi Shakil Ahmed