Aflatoxin B/G in Peanuts



Is the peanut a real nut? At least it is part of the name of the fruit. In the true sense, the peanut is a legume. Thus, peanuts are related to beans and peas. In contrast to real nuts, the fruit wall of peanuts is not woody, but only a pod.

The proportion of omega-3 fatty acids in legumes is also significantly lower than in nuts. Peanuts are not only tasty and nutritious, they are also indispensable in the food and feed industry.

Since peanuts in their raw state cause flatulence and abdominal pain, you won‘t find any raw peanuts in German supermarkets, only cooked or roasted peanuts. During further processing of the peanuts, mycotoxins may be produced
under incorrect storage conditions, which may be toxic to humans in a too high proportion. For this reason, strict import controls are carried out by the European Union.

Fully Automated Mycotoxin Analysis with FREESTYLE ThermELUTE™

For many laboratories, the challenge is to analyse as many samples as possible in less time. To facilitate this task, LCTech has developed the AflaCLEAN SMART column in addition to the AflaCLEAN immunoaffinity column. By using the 3.5 cm small SMART column, a particularly high sample throughput of 500 samples per week can be achieved.

The FREESTYLE ThermELUTE™ also enables fully automated mycotoxin analysis with results so sensitive that it is easy to measure far below the limit values. Each sample can be processed with the AflaCLEAN SMART column in FREESTYLE ThermELUTE™. This ensures 100 % performance for each sample and reliably prevents cross-contamination.

Processing Protocol

Homogenise 20 g of peanuts and add 1 g of sodium chloride. Extract the mixture with 100 mL methanol/ water (80/20 (v/v)) and add 50 mL n-hexane in order to remove fat and oil. Filtrate the raw extract and centrifuge it for the phase separation between the aqueous phase and the n-hexane phase with 3000 x g. Dilute 7 mL of the aqueous phase with 43 mL PBS.

When using the immunoaffinity column AflaCLEAN, load the extract onto the AflaCLEAN column. Wash the column with deionised water and elute it with 2 mL of methanol. Keep in mind that the methanol incubates
for 5 minutes into the column bed.

For processing with the AflaCLEAN SMART column use only 10 mL of the diluted extract (represents 0.28 g matrix). Load the 10 mL onto the AflaCLEAN SMART column with a flow rate of 3 mL/min. Wash the
column with 2 mL deionised water at the same flow rate. For elution, you only need 400 ?L methanol and therefore have a comparable toxin concentration as with the 3 mL column.

Find more details, recovery rates, HPLC-conditions and chromatograms here.

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