SCAR markers for adulterant detection in ground chilli

摘要

Purpose - This study aims to treat the development and application of sequence characterised amplified region (SCAR) markers for the detection of plant based adulterants (dried red beet pulp and powdered Ziziphus nummularia fruits) in traded ground chilli. Design/methodology/approach - Adulterant-specific DNA fragments (red beet pulp specific -"Beet 01" and Z. nummularia specific - "Ziz 01") identified by random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) analysis were cloned and sequenced for SCAR marker development. Red beet pulp specific SCAR primer pair, Bl, and Z. nummularia specific SCAR primer pair, Zl, were designed from the corresponding RAPD marker sequences to amplify SCAR markers of 320 bp and 389 bp, respectively. The utility of the SCAR markers for adulterant detection was verified in model blends of chilli powder with the adulterants. Six commercial samples of ground chilli powder were analysed using the SCAR markers. Findings - SCAR markers could detect the adulterants at a concentration as low as 10 g adulterant kg~(-1) of blended sample. The Z. nummularia SCAR marker could detect the presence of Z. nummularia fruit adulteration in one of the commercial samples. All the market samples tested were free from red beet pulp adulteration. Practical implications - The PCR-based method developed in the study is simple, rapid, and sensitive and has the potential to be developed into a quantitative analytical method and for commercial PCR kits for the large-scale screening of ground chilli to detect and prevent plant-based adulterants. The work has public health significance too, as ground chilli is one of the major spices consumed worldwide. Originality/value - The study is the first report on the development of SCAR markers for adulterant detection in ground chilli. This work has relevance, as adulteration is a major concern of the sanitary and phytosanitary issues of the World Trade Organization (WTO) agreement.