Abstract
Quercetin is a bioactive compound that has many beneficial effects on human health. Due to a lack of information about quercetin and quercetin derivatives in the Vietnam shallot, this work aimed to identify the quercetin family in shallot skin and flesh by liquid chromatography-mass spectrometry. Effect of extraction method (conventional solvent extraction and ultrasound-assisted extraction), including ethanol concentration (40–80%) and extraction time (15 to 60 mins) on the yield of quercetin were also investigated in this study. Quercetin, quercetin-glucoside and methylated-quercetin-hexose were commonly found in the extract of shallot flesh and skin. A very small amount of quercetin aglycone (0.7%) was found in flesh extract, while it was the most abundant in the skin sample (46.3%). The high content of quercetin-mono-glycoside was obtained in shallot extract (43.8% and 35.3% in the shallot flesh and skin, respectively). The flesh extract also contained high level of quercetin-di-glucoside (38.9%). About 14-16% of methylatedquercetin (-glucoside) were found in shallot bulb (both skin and flesh). It was found that ethanol concentration and extraction time directly affected on the quercetin extraction yield. The highest quercetin content was obtained in the sample which was extracted in 60% ethanol in combination with ultrasound-assisted extraction for 15 to 45 mins. The ultrasound-assisted extraction method improved quercetin yield by 13.38-15.64% and 49.46-56.88% for shallot skin and flesh compared to conventional solvent extraction. This study proved that ultrasound-assisted extraction could successfully be used for extraction of quercetin from shallot (both skin and flesh).
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Claims 12
Claim · model-written summary
Quercetin, quercetin-glucoside and methylated-quercetin-hexose occurred in flesh and skin extracts.
- Taxon
- shallot
Allium cepa var. aggregatume0 - Organ / stage
- flesh and skine0
- Outcome
- Quercetin, quercetin-glucoside and methylated-quercetin-hexosee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Quercetin, quercetin-glucoside and methylated-quercetin-hexose were commonly found in the extract of shallot flesh and skin.”
Claim · model-written summary
Quercetin aglycone was 0.7% in flesh extract.
- Taxon
- shallotAllium cepa var. aggregatume1
- Organ / stage
- fleshe0
- Outcome
- quercetin aglyconee0
- Value
- 0.7%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A very small amount of quercetin aglycone (0.7%) was found in flesh extract”
e1“extract of shallot flesh and skin”
Claim · model-written summary
Quercetin aglycone was 46.3% in skin.
- Taxon
- shallotAllium cepa var. aggregatume2
- Organ / stage
- skine0
- Outcome
- quercetin aglyconee1
- Value
- 46.3%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it was the most abundant in the skin sample (46.3%).”
e1“quercetin aglycone (0.7%) was found in flesh extract”
e2“extract of shallot flesh and skin”
Claim · model-written summary
Quercetin-mono-glycoside was 43.8% in flesh.
- Taxon
- shallotAllium cepa var. aggregatume0
- Organ / stage
- fleshe0
- Outcome
- quercetin-mono-glycosidee0
- Value
- 43.8%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The high content of quercetin-mono-glycoside was obtained in shallot extract (43.8% and 35.3% in the shallot flesh and skin, respectively).”
Claim · model-written summary
Quercetin-mono-glycoside was 35.3% in skin.
- Taxon
- shallotAllium cepa var. aggregatume0
- Organ / stage
- skine0
- Outcome
- quercetin-mono-glycosidee0
- Value
- 35.3%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The high content of quercetin-mono-glycoside was obtained in shallot extract (43.8% and 35.3% in the shallot flesh and skin, respectively).”
Claim · model-written summary
Quercetin-di-glucoside was 38.9% in flesh extract.
- Taxon
- shallotAllium cepa var. aggregatume1
- Organ / stage
- fleshe0
- Outcome
- quercetin-di-glucosidee0
- Value
- 38.9%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The flesh extract also contained high level of quercetin-di-glucoside (38.9%).”
e1“Vietnam shallot”
Claim · model-written summary
Methylatedquercetin glucoside comprised about 14–16% of shallot bulb skin and flesh.
- Taxon
- shallotAllium cepa var. aggregatume0
- Organ / stage
- bulbe0
- Outcome
- methylatedquercetin (-glucoside)e0
- Value
- 14-16%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“About 14-16% of methylatedquercetin (-glucoside) were found in shallot bulb (both skin and flesh).”
Claim · model-written summary
Ethanol concentration affected quercetin extraction yield.
- Taxon
- shallotAllium cepa var. aggregatume1
- Treatment
- ethanol concentratione0
- Outcome
- quercetin extraction yielde0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It was found that ethanol concentration and extraction time directly affected on the quercetin extraction yield.”
e1“Vietnam shallot”
Claim · model-written summary
Extraction time affected quercetin extraction yield.
- Taxon
- shallotAllium cepa var. aggregatume1
- Treatment
- extraction timee0
- Outcome
- quercetin extraction yielde0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It was found that ethanol concentration and extraction time directly affected on the quercetin extraction yield.”
e1“Vietnam shallot”
Claim · model-written summary
The highest quercetin content followed 60% ethanol and ultrasound for 15 to 45 minutes.
- Taxon
- shallotAllium cepa var. aggregatume1
- Treatment
- 60% ethanol in combination with ultrasound-assisted extraction for 15 to 45 minse0
- Outcome
- quercetin contente0
- Direction
- higheste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The highest quercetin content was obtained in the sample which was extracted in 60% ethanol in combination with ultrasound-assisted extraction for 15 to 45 mins.”
e1“Vietnam shallot”
Claim · model-written summary
Ultrasound extraction improved skin quercetin yield by 13.38-15.64% versus conventional extraction.
- Taxon
- shallotAllium cepa var. aggregatume0
- Organ / stage
- skine0
- Treatment
- ultrasound-assisted extraction methode0
- Outcome
- quercetin yielde0
- Direction
- improvede0
- Value
- 13.38-15.64%e0
- Comparator
- conventional solvent extractione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ultrasound-assisted extraction method improved quercetin yield by 13.38-15.64% and 49.46-56.88% for shallot skin and flesh compared to conventional solvent extraction.”
Claim · model-written summary
Ultrasound extraction improved flesh quercetin yield by 49.46-56.88% versus conventional extraction.
- Taxon
- shallotAllium cepa var. aggregatume0
- Organ / stage
- fleshe0
- Treatment
- ultrasound-assisted extraction methode0
- Outcome
- quercetin yielde0
- Direction
- improvede0
- Value
- 49.46-56.88%e0
- Comparator
- conventional solvent extractione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ultrasound-assisted extraction method improved quercetin yield by 13.38-15.64% and 49.46-56.88% for shallot skin and flesh compared to conventional solvent extraction.”
The same questions in other papers
ethanol · molecular: metabolites · Allium cepa (onion)Positive and negative results
1 in the opposite direction
- no effect
processing · yield · Allium cepa (onion)Positive and negative results
4 papers in the same direction as this paper · 3 in the opposite direction
- no effect
- no effect
- negative
4 papers more in this group
See all 8 papers →physical treatment · molecular: metabolites · Allium cepa (onion)Results agree
1 paper in the same direction as this paper
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.