Potentiometric method of plant microsuspensions antioxidant activity determination

• Published in: Food chemistry 2019-04, Vol.278, p.653-658
• Main Authors: Brainina, Khiena, Stozhko, Natalia, Bukharinova, Maria, Khamzina, Ekaterina, Vidrevich, Marina
• Format: Article
• Language: English
• Subjects: Antioxidant activity; Extract; Microsuspension; Plants; Potentiometry; Tea
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2018.11.098

•Simple and fast sample preparation technique for antioxidant activity measurement.•Using microsuspension of dried crushed plant as an analysed sample.•Realization of heterogeneous reaction between antioxidants and the mediator system.•Involvement antioxidants of liquid and solid fractions in signal-forming reaction. This paper focuses on the development of a simple, fast and reliable technique of sample preparation to be employed as part of potentiometric measurements of plant total antioxidant activity (AOA). Plant extracts and plant microsuspensions were analysed. The conditions for obtaining plant extracts were chosen: they exhibited the highest antioxidant activity at +80 °C and extraction time 20 min. A higher degree of dispersion of the analysed samples was accompanied by an increase in AOA of extracts and microsuspensions. The microsuspension enhanced effect results from the fact that antioxidants contained in both liquid and solid fractions are involved in the zone of a signal-generating reaction. The analysis of plant microsuspensions reduces the duration of AOA assessment. Comparison of the results of antioxidant activity of black and green tea microsuspensions with the results of the analysis of extracts prepared by a certified method showed no difference.