Bioactive polyphenolic compounds, water-soluble vitamins, in vitro anti-inflammatory, anti-diabetic and free radical scavenging properties of underutilized alternate crop Amaranthus spinosus L. from Gangetic plain of West Bengal

Studies associated with validation of folklore and ethnomedicinal claim of utilization of different plant parts of ‘spiny amaranth’ (Amaranthus spinosus L.) against degenerative diseases with chemical data, particularly the bioactive polyphenolic compounds and associated anti-degenerative properties are scanty and is the purpose of the present investigations. RP-HPLC coupled photodiode assay was employed for the quantification of twenty-one health promoting bioactive polyphenolic antioxidants derived from phenylpropanoid pathway from different plant parts of Amaranthus spinosus L. for validating organoleptic traditional claims as well as current trends in practice of this underutilized medicinal herb. Further, important water-soluble vitamins [vitamin B1, B2, B3, B6, B9] present in different plant parts were extracted and estimated through RP-HPLC for validating the claim of their functional food properties. The antioxidant-based functional food property of different plant parts of Amaranthus spinosus were corroborated from the data of in vitro free radical scavenging, metal-chelating, reducing, superoxide radical scavenging, hydroxyl radical scavenging, anti-protein coagulation, anti-lipid peroxidation and antidiabetic properties. When compared, a positive correlation in accumulation of polyphenolic compounds and water-soluble vitamins tested with antioxidant attributes were noticed for different plant parts, strongly substantiating their phytonutrient properties. Taken as a whole, the present work provides data on organ-specific bioavailability of bioactive polyphenolic antioxidant compounds, water soluble B- vitamins and their functional attributes for validating traditional claims as well as existing trends in consumption of this underutilized medicinal vegetable as low-cost natural antioxidant supplement and functional food, which may encourage their effective exploration and utilization.