Extraction Rate Of Flavonoids Research Articles

Optimization of Cellulase-Assisted Extraction of Total Flavonoids from Equisetum via Response Surface Methodology Based on Antioxidant Activity

Flavonoids are one of the most essential compounds in various plants. This study used the cellulase-assisted method to extract flavonoid-enriched antioxidants from Equisetum arvense L. (EAL). According to a three-factor and three-level central composite design, the response surface methodology was used to obtain the maximum total flavonoid yield, thereby providing the most potent antioxidant activity of EAL extracts. The results indicated that the optimal condition for the total flavonoid extraction was 0.52% (base substrate) enzyme concentration and enzymolysis for 50.58 min at 49.03 °C. The extraction rate of flavonoids from horsetail reached 4.88 mg/g under these optimal conditions. The yield was 51.23% higher than that from the traditional solid–liquid extraction method. The highest DPPH-scavenging ability of the extracts obtained under 0.50% enzyme concentration and enzymolysis for 49.41 min at 46.59 °C was 77.36%. HPLC results revealed that the antioxidant substances had diverse flavonoids. Thus, the extraction condition was consistent for antioxidant activity and total flavonoids. Therefore, the current study provided an efficient method to extract flavonoid compounds from EAL, facilitating technical support for utilizing the plant.

Response surface methodology-optimized extraction of flavonoids from pomelo peels and isolation of naringin with antioxidant activities by Sephadex LH20 gel chromatography

In this study, flavonoids were extracted from pomelo peels and naringin was isolated from the flavonoid extract. The effects of extraction parameters, namely, ethanol concentration, solid-to-liquid ratio, and extraction time, on the yield of flavonoids extracted from pomelo peels were analyzed according to the Box-Behnken design of response surface methodology. The experimental conditions for flavonoid extraction were optimized, and naringin was separated from the extracted flavonoids using Sephadex LH-20 column chromatography. Experimental results showed that the influence of factors on the extraction rate of flavonoids from pomelo peels was in the order of ethanol concentration > solid-to-liquid ratio > extraction time, and the optimal extraction parameters were 85% ethanol concentration, 1:20 solid-to-liquid ratio, and 4-h extraction time for extracting flavonoids from pomelo peels. Under these conditions, the yield of flavonoids was 6.07 ± 0.06 mg/g. After three times of extraction, the flavonoid extraction rate reached 96.55%, and the residual naringin in the pomelo peels was 0.017 mg/g, at which point the bitterness in the pomelo peels disappeared. Two components, namely, PF1 and PF2, were separated from the crude flavonoid of pomelo peels through Sephadex LH20 column chromatography. PF2 was identified as naringin by high-performance liquid chromatography tandem mass spectrometry, with a purity of 95.7 ± 0.23%. Both flavonoids and PF2 exhibited good in vitro radicals scavenging activities on DPPH, ABTS, superoxide anion and hydroxyl.

Optimization of Ultrasonic-assisted Extraction Process of Flavonoids from Damiana by Response Surface Methodology and Its Antioxidant Activity

The purpose of this study was to determine the optimal extraction process conditions for flavonoids from damiana. Taking the extraction rate of flavonoids as an indicator, the effects of factors such as ultrasonic time, temperature, ultrasonic power, and material-to-liquid ratio on the extraction rate of damiana flavonoids were investigated through experiments. Through response surface tests, a regression mathematical model was established and variance analysis was performed to determine the best conditions for extracting turner grass flavonoids. At the same time, the scavenging rate of DPPH free radicals and ABTS free radicals and reducing power were used as indicators to evaluate the antioxidant activity of the crude extract of damiana flavonoids. The results showed that the optimal extraction process conditions were ultrasound time 42 min, temperature 70 ℃, ultrasound power 320 W, and ethanol volume fraction 82%. Under these conditions, the extraction rate of damiana flavonoids reached 94.4%. Tests showed that the IC50 values of flavonoids of damiana in scavenging DPPH free radicals and ABTS free radicals were 0.0283 and 0.0272 mg/mL, respectively. The reducing force were stronger than VC. This optimized process is feasible, and flavonoids from damiana have good antioxidant properties.

Study on extraction technology of flavonoids from natural green cotton fiber

Studies have shown that the number of flavonoids between colored cotton and dyed cotton is quite different. Flavonoids content of natural colored cotton is higher than that of white cotton or dyed cotton, so natural colored cotton and dyed cotton can be distinguished by the content of flavone in fibers. Extraction of flavonoids is essential for identification, but there is a lack of simple and trustable extraction method in the market so far for this purpose. This study aim is to explore the most effective method of extracting flavonoids from cotton fibers. Single factor experiment and orthogonal experiment have been designed to get the effect of experimental conditions on the extraction of flavonoids from cotton fibers, and the optimized extraction process has been obtained. Five variables, including the liquid-solid ratio, ethanol concentration, extraction temperature, extraction time, sodium hydroxide concentration, were selected as the main factors, and each factor was studied at four levels. The UV absorbance value at 264 nm was used to evaluate the effect of different extraction conditions on the extraction rate of flavonoids from natural green fibers. The results showed that the extraction efficiency was influenced mostly by ultrasonic temperature, followed by ethanol concentration, the liquid-solid ratio, sodium hydroxide concentration and ultrasonic time. The optimized extraction conditions have been concluded as 1:40 liquid-solid ratio, 50% ethanol concentration, 70 °C extraction temperature, 1 h extraction time, 0.15% sodium hydroxide concentration.

Extraction of flavonoids from Chrysanthemum morifolium and antitumor activity in vitro.

The aim of the present study was to optimize flavonoid extraction from Chrysanthemum morifolium and to study the antitumor effects of flavonoids on human gastric cancer MKN45 cells in vitro. A single factor experiment was designed and the extraction process was optimized using an orthogonal test. MKN45 cells were treated with different concentrations of flavonoid from Chrysanthemum morifolium for 24 and 48 h and the inhibitory effect on the MKN45 cells was evaluated using an MTT assay. Following staining with Annexin V-fluorescein isothiocyanate/propidium iodide, flow cytometry was performed. The optimized flavonoid extraction conditions were as follows: Duration of ultrasonic treatment: 35 min; ethanol concentration: 75%; extraction temperature: 80°Cand liquid-to-solid ratio 25: 1. Under the above conditions, the extraction rate of flavonoids was 5.24%. When compared with a blank control group, flavonoids extracted from Chrysanthemum morifolium inhibited the proliferation of MKN45 cells in a dose- and time-dependent manner. Furthermore, in cell groups treated with low, moderate and high concentrations of flavonoid, it was observed that the proportion of apoptotic cells increased in a dose-dependent manner. The extraction process optimized by the orthogonal test achieved a high yield and satisfactory extraction efficiency. Additionally, the experiment demonstrated that flavonoids from Chrysanthemum morifolium inhibited the growth of MKN45 cells and induced their apoptosis. Thus, flavonoids from Chrysanthemum morifolium exerted antitumor effects on MKN45 cells, which may be exploited as a potential antitumor therapeutic for gastric cancer.

Separation and purification of flavonoids from Artemisia annua L.by polyethylene glycol-ammonium sulfate aqueous two-phase system

An aqueous two- phase system of PEG- ( NH4) 2SO4was used to extract flavonoids from the crude ethanol extract of Artemisia annua L..The effects of average molecular weight of PEG, mass percent of ( NH4) 2SO4, mass percent of PEG, pH and temperature on partition coefficient and extraction rate of flavonoids were explored by single factor experiments, then the extraction condition of flavonoids was further optimized by orthogonal method.Then the optimum conditions were obtained as follows: An aqueous two- phase system of 30% PEG600 and 25% ( NH4) 2SO4, pH of 3 and temperature of 45℃.Under the optimal extraction conditions, flavonoids from Artemisia annua L.was mainly distributed in the upper phase with a partition coefficient of 21.86 and the extraction rate of 96.33%.

Extraction and Antioxidant Activity of Ultrasonic-Assisted Flavonoids from<i> Suaeda salsa</i>

The box-behnken design combined with response surface methodology was used to optimize ultrasonic-assisted extraction of flavonoids from Suaeda salsa (Linn.) Pall. The results indicate that the highest extraction rate of flavonoids by ultrasonic-assisted extraction could arrive 5.17% using 500W ultrasonic power, 69% ethanol as solvent, 77°C extraction temperature, 1:40 solid to liquid ratio for 58 min extraction. The flavonoids-enriched extracts exhibited quite strong reducing property and excellent inhibitions of DPPH radical, hydroxyl radical. Meanwhile, it was found that the bioactivities appeared to be dose-dependent of flavonoids.