Microwave assisted direct saponification for the simultaneous determination of cholesterol and cholesterol oxides in shrimp

Author(s)

Souza, Hugo A. L. ; Mariutti, Lilian R. B. ; Bragagnolo, Neura

• Document type: Journal article
• Source: JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY; v. 169, p. 8-pg., 2017-05-01.

Abstract

A novel microwave-assisted direct saponification method for the simultaneous determination of cholesterol and cholesterol oxides in shrimp was developed and validated. Optimal saponification conditions, determined by means of an experimental design, were achieved using 500 mg of sample and 20 mL of 1 mol/L KOH ethanol solution for 16 min at 45 degrees C at maximum power at 200 W and magnetic stirring at 120 rpm. Higher extraction of cholesterol oxides in a reduced saponification time (similar to 75 times) was achieved in comparison with the direct cold saponification method. The new method showed low detection (<= 0.57 mu g/mL) and quantification (<= 1.73 mu g/mL) limits, good repeatability (<= 10.50% intra-day and <= 8.56% interday) and low artifact formation (evaluated by using a deuterated cholesterol D6 standard). Raw, salted and dried-salted shrimps were successfully analyzed by the validated method. The content of cholesterol oxides increased after salting and decreased after drying. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 13/06489-1 - Formation and inhibition of compounds generated by oxidative reactions in lipids of Nile Tilapia
• Grantee: Neura Bragagnolo
• Support Opportunities: Regular Research Grants