Novel method for the detection of adulteration of saffron with gardenia

The object of the invention is the development of a process for the detection of adulterations of saffron with gardenia based on the detection of geniposide by Liquid Chromatography with High–Resolution Mass Spectrometry detection.

The procedure for the determination of geniposide is based on the use of a C18 column and a liquid chromatography equipment coupled to a quadrupole-time-of-flight (QTOF) Mass Spectrometry (MS) detector through an ionization source by orthogonal electrospray with Jet Stream thermal focus technology. The mass spectrometer is equipped with an Agilent Technologies Mass Hunter software for mass spectrometer control and the data acquisition and analysis.

The analytical characteristics evaluated by the procedure, object of the invention are:

• Linearity: it was evaluated as the range of working concentrations between 0.8 and 8 μg/mL geniposide.
• Detection limit: it was evaluated as the concentration of geniposide that gives a value of the signal-to-noise ratio of 3. The limit is 0.01 μg/mL, which allows to detect about 42 μg of geniposide per gram of analyzed sample that is up to 0.0042%, a value that demonstrates the high sensitivity of the method developed for the determination of geniposide in saffron.
• Limit of quantification: it is evaluated as the concentration of geniposide that results in a value of the signal-to-noise ratio of 10, obtaining a limit of 0.03 μg/mL.
• Precision: it is evaluated as instrumental repeatability and intermediate precision. The instrumental repeatability is determined as the value of the relative standard deviation (RSD) in % for the peak areas obtained when 3 consecutive injections of a standard geniposide solution are performed at two concentration levels (0.8 and 8 μg/mL) and at a solution of an authentic adulterous saffron sample with percentages of 10 and 90 % of gardenia extract. The values ​​obtained for RSD were lower than 1.5 %. Intermediate precision was determined from the RSD values ​​of the peak areas obtained by injecting (replicate for two consecutive days) three replicates of a standard geniposide solution at two concentration levels (0.8 and 8 μg/mL) and at a solution of a sample of authentic saffron adulterated with percentages of 10 and 90 % of extract of gardenia. The values ​​obtained for the RSD were inferior to 1.8 % for the standard solutions of geniposide and to 2.9 % for the samples of saffron.
• Accuracy: it was evaluated as the recovery obtained for the geniposide when a sample of authentic saffron was enriched with standard geniposide at a concentration of 1 μg/mL. The average recovery values ​​obtained were 89 ± 14 %.

Intellectual property status

Patent already applied for

Patent application number : P201600133

Where : Spanish Patent and Trademark Office

Current development status

Developed, available for demonstration

Desired business relationship

Patent licensing

Commercial agreement with technical assistance

Technical cooperation