Comparison of microwave and ultrasound-assisted extraction techniques for leaching of phenolic compounds from nettle - PubMed (original) (raw)

Comparison of microwave and ultrasound-assisted extraction techniques for leaching of phenolic compounds from nettle

Alev Emine Ince et al. J Food Sci Technol. 2014 Oct.

Abstract

In this study, extraction of phenolic compounds from nettle by microwave and ultrasound was studied. In both microwave and ultrasound-assisted extractions, effects of extraction time (5-20 min for microwave; 5-30 min for ultrasound) and solid to solvent ratio (1:10, 1:20, and 1:30 g/mL) on total phenolic content (TPC) were investigated. Effects of different powers (50 % and 80 %) were also studied for ultrasound-assisted extraction. In microwave-assisted extraction, the optimum TPC of the extracts (24.64 ± 2.36 mg GAE/g dry material) was obtained in 10 min and at 1:30 solid to solvent ratio. For ultrasound-assisted extraction, the condition that gave the highest TPC (23.86 ± 1.92 mg GAE/g dry material) was 30 min, 1:30 solid to solvent ratio, and 80 % power. Extracts obtained at the optimum conditions of microwave and ultrasound were compared in terms of TPC, antioxidant activity (AA) and concentration of phenolic acids with conventional extraction and maceration, respectively. Microwave reduced extraction time by 67 %. AA of extracts varied between 2.95 ± 0.01 and 4.48 ± 0.03 mg DPPH/g dry material among four methods. Major phenolic compounds were determined as naringenin and chlorogenic acid in nettle.

Keywords: Leaching; Microwave; Nettle; Phenolic; Ultrasound.

PubMed Disclaimer

Figures

Fig. 1

Fig. 1

Total phenolic contents (TPC) of nettle extract obtained a by microwave-assisted extraction at different solid to solvent ratios (♦) 1:10, (■) 1:20, (▲) 1:30, for different extraction times, b conventionally at 1:30 solid to solvent ratio for different extraction times, and c by ultrasound-assisted extractions at different conditions (♦) 50 % power and 1:10 solid to solvent ratio, (■) 50 % power and 1:20 solid to solvent ratio, (▲) 50 % power and 1:30 solid to solvent ratio, (◊) 80 % power and 1:10 solid to solvent ratio, (□) 80 % power and 1:20 solid to solvent ratio, (Δ) 80 % power and 1:30 solid to solvent ratio (n = 2)

References

    1. Abbasi H, Rezaei K, Emamdjomeh Z, Mousavi SME. Effect of various extraction conditions on the phenolic contents of pomegranate seed oil. Eur J Lipid Sci Technol. 2008;110:435–440. doi: 10.1002/ejlt.200700199. -DOI
    1. Alekovski S, Sovova H, Curapova B, Poposka F. Supercritical CO2 extraction and Soxhlet extraction of grape seeds oil. Bull Chem Technol Maced. 1998;17:129–134.
    1. Al-Ismail K, Herzallah SM, Rustom AS. Antioxidant activities of some edible wild Mediterranean plants. Ital J Food Sci. 2007;19:287–296.
    1. Arbianti R, Utami TS, Kurmana A, Sinaga A (2007) Comparison of antioxidant activity and total phenolic content of Dillenia indica leaves extracts obtained using various techniques. In: 14th Regional Symposium on Chemical Engineering, Gadjah Mada University, Yogyakarta-Indonesia, 4–5 December 2007
    1. Bayramoglu B, Sahin S, Sumnu G. Solvent-free microwave extraction of essential oil from oregano. J Food Eng. 2008;88:535–540. doi: 10.1016/j.jfoodeng.2008.03.015. -DOI

LinkOut - more resources