Quality Variation and standardization of black pepper (Piper nigrum): A comparative geographical evaluation based on instrumental and metabolomics analysis.

Black pepper (Piper nigrum), known as "king of spices", from various geographical origin is available in Saudi Arabia market where its demand as a food as well as a medicine for minor ailment is increasing. However, a lack of appropriate information exists for these samples in terms of quality variation and standardization.to evaluate the quality and standardize the black pepper sample with respect to its physicochemical characters, active principle variation i.e. Piperine (PPN), toxicity and biological activity. The main focus is to validate, is any difference do exist in quality and quantity of active principle present in these samples?For physicochemical analysis (chemical tests, ash values), instrumental analysis (ASE, UHPLC-DAD, IR, NMR, ICP-MS), whereas for biological evaluation in vitro antioxidant activity (DPPH and ABTS) and cytotoxicity assay was conducted.An extract yield (g) with %recovery 2.26 ±4.24 (11.3%) was obtained for Vietnam sample, using a fast and rapid method of extraction (ASE), followed by Pakistani 1.22 ±2.64 (6.1%) and Indian sample 0.75 ±1.69 (3.75%). Physicochemical tests revealed the presence of flavonoids and phenolic compounds in all samples whereas ash values revealed a low amount of total-, acid insoluble- and high water soluble ash in Vietnam sample. IR and NMR further helped in standardization of the samples. ICP-MS analysis showed a high amount of macro- and micronutrient in Saudi Arabian sample. UHPLC analysis revealed a high amount of PPN (ng/mL) in Pakistani sample (1362614.09) followed by Vietnam (1051848.04) and Indian sample (768512.81). In vitro antioxidant and cytotoxicity activity revealed more potential for Vietnam sample.The samples were properly standardized and effectively differentiated in terms of quality and biological activities using fast and reliable tools, however it certainly does not mean that a particular geographical region is more better or productive in terms of herbal products.