Liquorice (bot.), also known as real liquorice, belongs to the legume family. By extracting the root and adding various ingredients such as sugar syrup or flour, the typical sweetness is created. Liquorice is not only used as a stimulant, as in sweets or drinks, but is also used in medicine.
Even in ancient Rome, people knew about the health-promoting effects of liquorice. Liquorice was used to treat throat and stomach ailments. Today, the Middle East is one of the classic growing regions for genuine liquorice. Licorice as a confectionery is consumed worldwide. Especially the Dutch have a special preference for licorice, so called „Drop“.
Ochratoxin A in Difficult Matrices
Ochratoxin A is a naturally occurring mycotoxin produced by moulds of the genera Aspergillus and Penicillium as primary contamination. Ochratoxin A is also found in liquorice due to its high liquorice (Glycyrrhiza glabra) content. Nearly all liquorice (bot.) has levels of ochratoxin A. The essential oils and vegetable colourings, as well as the high sugar content of liquorice often are challenges during sample preparation. LCTech offers with the immunoaffinity columns OtaCLEAN and the robotic system FREESTYLE SPE an efficient sample preparation. More samples in less time and high cost savings.
Any manual SPE method that has proven itself in your laboratory can be directly transferred to the system. Already created methods can be saved and reused, but also modified. Even with difficult matrices, such as liquorice, show very good recovery rates.
Homogenise 20 g of liquorice and add 2 g of sodium chloride. Extract the sample by 100 mL methanol/water (80/20 (v/v)) and add 50 mL of n-hexane in order to remove fat and essential oils for at least 20 minutes. Filter the raw extract and dilute 2 mL of the n-hexane free phase with 12mL PBS (contains 8 % Tween).
Load the sample onto the immunoaffinity column OtaCLEAN. Ensure that the flow rate does not exceed 2mL/min. Then rinse the sample reservoir with 5 mL deionised water and load the washing solution onto the column. Wash the column again with 5 mL deionised water. Afterwards, you can remove any residual liquid from the column with a short flush of air. Elute the toxin with methanol. Keep in mind that the column bed is incubated with methanol for 5 minutes to ensure a fully denaturation of the antibodies and release of toxin.
Find more details, recovery rates, HPLC-conditions and chromatograms here.
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