Development of DNA and GC-MS Fingerprints for Authentication and Quality Control of Piper nigrum L. and Its Adulterant Carica papaya L.

Abstract

Piper nigrum L. (family: Piperaceae) is cultivated for its mature fruit/berries. Generally dried, they are one of the most important commercial spice/food additives. The dried fruit of P. nigrum is almost similar in morphology to seeds of Carica papaya L. and is used as an adulterant of P. nigrum. Molecular technology and plant metabolomics are effective tools for unequivocal authentication and detection of food ingredients. In this study, DNA fingerprinting-based quality control markers [sequence characterized amplified region (SCAR) markers] were employed for authentication and discrimination of P. nigrum from its adulterant C. papaya. The 500- and 750-bp-sized SCAR markers of P. nigrum and C. papaya were amplified using their specific SCAR primer sets. Further, metabolic profiling was carried out using gas chromatography–mass spectrometry (GC-MS) on the fruits and seeds of P. nigrum and C. papaya, respectively. For P. nigrum and for C. papaya, 84 and 61 chemically diverse metabolites were observed, respectively, among which 44 and 33 metabolites were putatively selected, respectively. The detection efficiency of GC-MS was assessed by combining the powdered samples of both P. nigrum and C. papaya in different ratios and was able to detect as low as 20 mg/g (w/w) (20,000 ppm) of metabolites. Multivariate data analysis and clustering analysis was performed on the mixture samples of both the food ingredients. Thus, development of SCAR markers along with the phytochemical fingerprints can correlate DNA fingerprinting data with the quantity of active ingredient and/or phytochemical constituents associated with the specific spice/herb/(s).