Table 2.

Novel extraction of QUR from agricultural products.

Technique	Matrix	Optimum conditions and extraction yield	References
UAE	Euonymus alatus (Thunb.) Sieb	Aqueous ethanol 70 %, extraction time 3 × 30 min, solvent: sample ratio 40:1 (v/w), and QUR extraction yield 0.29 mg/g	[160]
	Raphanus sativus L.	Ultrasound intensity 50%, frequency 50/60 KHz, time 10 min, solvent methanol and QUR extraction yield 11.8%	[25]
	Onion solid wastes	Ethanol 59%, temperature of 49 °C, and total QUR yield 11.08 mg/g dry weight	[24]
	Dendrobium officinale	Ethanol 90%, Temperature 50 °C, Time 60 min, power 140 W, liquid ratio 60%, and QUR yield 4.3385 µg/g	[161]
	Apple Peels	Treatment time 15 min of ultrasound wavelengths of dehydrated apple peel powder in 80% to 100% (v/v) methanol in 1:50 (w: v) solid to solvent ratio provided the optimum extraction conditions for quercetin	[162]
	Onion skin	Treatment time 21.7 min, power 606.4 W with 43.8% ethanol and QUR yield 20.3%	[31]
	Allamanda cathartica	Total flavonoids yield was 172.90 mg QE/g and QUR yielded 51.39 mg/g	[163]
	Abies nephrolepis (Trautv.)	Ultrasound power of 160 W, frequency of 45 kHz, the temperature of 332.19 K, extraction time 39.25 min, the ethanol concentration of 50%, a liquid–solid ratio of 20 mL/g, and QUR yielded 69.59 ± 2.57 mg/g	[27]
	Cabbage	Sonication by 60:40 methanol/water (v/v), temperature 30 °C, time 40 min, and QUR yielded 1378. 9 μg/mL	[164]
	Hypericum perforatum L.	Extraction temperature 67 °C, time 67 min, HCl concentration 1.2 M, methanol concentration 77% (v/v) and QUR yielded 10.81 mg/g	[165]
	Flos populi	Temperature 70 °C, liquid–solid ratio 25 mL/g, particle diameter 0.18 mm, ethanol concentration 60%, ultrasonic time 35 min, ultrasonic intensity 3.3 W/cm2 and two experimental runs. Under these optimum conditions, approximately 16.26 mg of QUR was obtained from 1 g of Flos populi	[26]
MWAE	Stalks of Euonymus alatus (Thunb.) Sieb	MW power 170 W, irradiation time 6 min, 50% ethanol (v/v) solution, extractant volume 40 mL	[166]
	Solid Onion (Allium cepa L.)	MW irradiation for 150 sec at pH 6.25 yielded QUR 209 mg/ 100 gm fresh weight	[32]
	Red Kidney Bean	Solvent 60 w/w% acetone, solvent to solid ratio was 10:1 and the MW irradiation power 800 W, treatment time 1 min and QUR yielded 35.8 mg/g	[167]
	Carica papaya flower	Solid to liquid ratio (1:15), MW power 400 W, extraction time 4 min, and QUR yielded 0.214%	[33]
	Latinos edodes stem	MW radiation power 385 W, irradiation time 50 s, ethanol concentration 50%, liquid-to-solid ratio was 30:1 (mL: g) and QUR yielded 0.75–0.02) mg/g	[168]
UMWAE	Red onion skin wastes	MW irradiation time 60 s followed by sonication time 15 min at 70 °C, 70% ethanol, solvent to solid ratio of 30 mL/g and yielded QUR 7.66% and total flavonoids10.18%	[169]
	Iranian Propolis	MW power 300 W, irradiation time 1.5 min and ultrasound treatment time 10 min and temperature 40 °C. obtained QUR yield 44.53%	[170]
SFE	Sumac (Rhus coriaria L.)	Temperature 40οC, pressure 250 bar, 6% ethanol content and yielded QUR 2196 μg/100 g	[171]
	Onion skin	Extraction time 15 min, temperature 165 °C, the mixture ratio of 1.5:2.5 for onion skin and diatomaceous earth and yielded QUR 16.29 ± 0.75 mg/g	[172]
	Rosa damascene Mill	The temperature of 46.3 °C, Pressure 25.5 MPa, CO2 flow rate of 0.7 mL/min, extraction time of 120 min and yielded QUR 32.0%	[41]
	Phyllanthus niruri Callus Culture	Temperature 60 °C, pressure 200 bars, time 30 min and yielded QUR 1.72%	[173]
	Taxus chinensis	Temperature 46 °C, pressure 24 MPa, time 2.3 h, solvent 82% ethanol and yielded QUR 3.73 mg/g	[174]
EAE	Medicage Stativa L.	Enzymolysis time 92 min, ethanol concentration 22%, liquid/solid ratio was 40: 1 (m L/g) and yielded QUR 12.56 μg/g	[175]
	Onions	Ethanol concentration 5%, flow rate 3 mL/min, temperature 84 °C, pH 5.5, and yielded maximum QUR	[46]
	Onion peel waste	Pectinase 0.16 mg, cellulose 0.72 mg, xylanase 1.0 mg, and QUR yield was enhanced by 1.61 folds	[47]