Extraction of antioxidants from plants using ultrasonic methods and their antioxidant capacity

Abstract

The analytical method based on the HPLC coupled with UV detection (HPLC-UV) for the determination of selected antioxidants (i.e. esculetin, scopoletin, 7-hydroxycoumarine, rutin, xanthotoxin, 5-methoxypsoralen and quercetin) in plant material was developed. Two ultrasonic extraction methods for the isolation of these compounds from the plants such as Mentha longifolia L., Mentha spicata L., Ruta graveolens L., Achyllea millefolium L., Plantago lanceolata L. and Coriandrum sativum L. were used. Both of these methods, i.e. ultrasonic probe and ultrasonic bath, were optimised and compared to each other. For the proposed HPLC-UV method LOQ values in the range from 22.7 (xanthotoxin) up to 97.2 ng/mL (rutin) were obtained. For all extracts the antioxidant capacity based on the reduction of free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical was also determined. Obtained results ranged from 10.11 up to 73.50% of DPPH radical inhibition.

Comparison of pressurised fluid and ultrasonic extraction methods for analysis of plant antioxidants and their antioxidant capacity

“…Thus, it is crucial to perform the respective optimisation in order to obtain the good recovery strategy forms. Because this optimisation was already performed and published [18], in this work only final extraction conditions are presented. So it was found that 0.75 g of sample, 50 mL of 30% acetonitrile in water as extraction solvent at 25°C for 25 minutes are suitable conditions for USE method.…”

“…For identification of individual compounds as well as for their quantification the standard addition method was chosen. HPLC/UV used in this study was based on the method applied in our previous study [18], but some modifications connected with the column exchange were performed. The chromatographic conditions were changed into those presented in the experimental part, whereas the suitable separation of individual target compounds was obtained.…”

“…The main goals of the present study were to optimise the experimental conditions of pressurised fluid extraction for the determination of herbal antioxidants and to compare the proposed PFE method with the ultrasonic extraction method developed in our previous study [18]. To this purpose the determination of selected antioxidants contents together with the evaluation of appropriate antioxidant capacities obtained by DPPH method for ten different plant samples were used.…”

“…All USE extractions were performed according to our previous manuscript [18]. Extraction conditions were as follows: ca 0.75 g of plant sample, 50 mL of the extraction solvent (30% of acetonitrile in water), temperature 25°C for 25 minutes, extracts filtered through the Target, PTFE 0.45 μm filter into the 50 mL volumetric flask and analysed by HPLC/ UV.…”

Development of Advance Extraction Methods for the Extraction of Myristicin from Myristica fragrans

“…This technique enables rapid extraction with high power ultrasound waves, yet it has a disadvantage of allowing only one sample extraction at the time, and it is performed in open vessels. UAE-S has been successfully applied for extraction of small organic compounds from plant material (Torre et al 2001;Wu et al 2001;Adam et al 2009;Sanz-Landaluze et al 2010;Jerman Klen and Mozetič Vodopivec 2012), but to the authors' best knowledge, it has not been used for extraction of myristicin before.…”