Comparative Quantification of the Phenolic Compounds, Piperine Content, and Total Polyphenols along with the Antioxidant Activities in the <i>Piper trichostachyon</i> and <i>P. nig... oleh Jameel Mohammed Al-Khayri, Vinayak Upadhya, Sandeep Ramachandra Pai, Poornananda Madhava Naik, Muneera Qassim Al-Mssallem, Fatima Mohammed Alessa