A rapid screening for adulterants in olive oil using DNA barcodes

A distinctive methodology is developed to trace out the mixing into olive oil, which is marketed every year with 20% or more fraudulent oils. Such adulteration has been difficult to differentiate using fatty acid analysis and other available current techniques, as chemically fatty acids are same regardless of their source. The total genomic DNA isolated from olive oil, contaminated with canola and sunflower was analysed for single nucleotide polymorphism (SNP) variation in noncoding spacer region between psbA-trnH and partial coding region of matK of plastid genome. These DNA regions were amplified by PCR using specific primers and resulting DNA sequences were matched to the predetermined consensus DNA barcode sequences of canola and sunflower for discerning the contaminations in olive oil samples. The matching of an adulterant DNA sequence with their respective DNA barcode revealed the mixing of canola and sunflower oil into olive is simpler way and the combined approach of molecular biology and bioinformatics technology can be used as an inexpensive method for ensuring the purity of olive. This plastid based molecular DNA technology can be used for rapid detection of adulteration easily up to 5% in olive oil.