Variations in the Morphology, Total Phenols and Antioxidant Activity in Different Germplasm of Piper longum L. from North-East India

Piper longum L., commonly referred to as long pepper occupies a prominent position within traditional medicinal frameworks worldwide due to its multifaceted pharmacological attributes. In the present study, ten germplasms of Long Pepper were evaluated for morphological and yield attributing characteristics, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Analysis of variance revealed significant differences among the germplasms for all traits, indicating a considerable degree of variability. The plant height varied from 53.33 to 116.67 cm and the internodal length was highest in JPL31 (6.57 cm). Petiole length ranged from 3.23 to 5.47 cm, with the highest in JPL31. JPL21 recorded the highest spike length of 3.53 cm. The number of spikes ranged from 51.33 (JPL6) to 109.67 (JPL31), and the spike fresh weight ranged from 32.64 to 66.50 g per plant. The highest spike dry weight of 9.27 g was observed in JPL31 and lowest in JPL6 (5.07 g). Alkaloid content was confirmed by the formation of orange-red and yellow-creamy precipitation by Dragondroff’s and Mayer’s tests, respectively. The highest TPC and TFC contents were recorded in the check variety “Viswam,” followed by JPL3. In addition, “Viswam” recorded the highest antioxidant activity against both DPPH (IC₅₀-64.55 μg/ml) and hydroxyl radicals (IC₅₀-54.60 μg/ml).