Response Surface Optimized Ultrasonic-Assisted Extraction of Flavonoids from Sparganii Rhizoma and Evaluation of Their in Vitro Antioxidant Activities

Abstract

An efficient ultrasound-assisted extraction technique was employed to extract total flavonoids from Sparganii rhizoma. The optimum extraction conditions for the highest yield of total flavonoids were ethanol concentration 53.62%, ultrasonication time 29.41 min and ultrasound power 300 W, which were determined using response surface methodology. The extraction yields of the optimal ultrasound-assisted extraction were higher than using conventional extraction. The crude extract was then purified on a polyamide resin, whereby the flavonoids content in the purified extract increased to 94.62%. The antioxidant activities of the purified flavonoids including DPPH radical scavenging activity, ABTS+ radical scavenging activity, reducing power, hydroxyl radical scavenging activity and superoxide anion scavenging activity, were evaluated in vitro, which suggested that the flavonoids showed significant antioxidant activities. Rutin, kaempferol and formononetin were identified in the extract by comparing relative retention times and UV-Vis spectra with those of reference standards.

Ultrasonic-Assisted Extraction of Antioxidant Phenolic Coumpounds From Eucheuma Cottonii

“…This result agreed that extraction time is an important variable in UAE of phenolic compounds from plant materials. A longer extraction time permits more contact time for the cavitation bubbles to rupture more plant cells, result in an increase of the TPC extracted (Wang et al, 2012). The result was in accordance with Han et al (2012) who reported the improvement of phenolic of Betel nut seed with time by using UAE method, respectively.…”

Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method

“…In several studies, different amounts of flavonoids have been found in alfalfa tissues, which indicated that it may be utilized as a potential natural antioxidant compound [9][10][11][12]. Alfalfa may be a promising resource for flavonoids in the future.…”

Response Surface Optimized Extraction of Total Triterpene Acids from <i>Eriobotrya japonica</i> (Thunb) <i>Lindl</i> (Loquat) Leaf and Evaluation of their In vitro Antioxidant Activities

“…It was clear that the model fit well with the response variables, considering the model could explain the variability of the responses. The coefficient of multiple determination (R2) was 0.9887, proving that a high correlation was obtained [13].…”