Abstract
A pectolytic enzyme preparation from Aspergillus niger (pectinase AN) decreased most rutin content and antioxidant activity of asparagus juice. To investigate the mechanism of such loss, we analyzed several possible related enzyme activities in pectinase AN. We found that the activity of pectinase AN to oxidize guaiacol had no significant difference with or without the presence of H2O2; thus it was laccase activity, not peroxidase (PO) activity, that pectinase AN contained. We did not find any polyphenol oxidase (PPO) activity in pectinase AN. Laccase in pectinase AN could be the major cause of loss of rutin and antioxidant activity of asparagus juice. When most laccase activity of pectinase AN was inactivated after heating at 70 degrees C for 1.5 min and incubated with asparagus juice, the loss rate of rutin was only 9% of that treated with unheated pectinase AN, and the antioxidant activity was even increased. Rhamnosidase activity was detected in pectinase AN and can change rutin in asparagus juice to quercetin-3-glucoside, which has higher antioxidant activity than rutin. This may explain the increase of antioxidant activity of asparagus juice treated with heated pectinase AN that still contained some rhamnosidase activity. The discovery of our research is helpful to produce juice with high antioxidant activity and high health benefits in the juice industry.
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Claims 9
Claim · model-written summary
Pectinase AN reduced rutin in asparagus juice.
AsparagusNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A pectolytic enzyme preparation from Aspergillus niger (pectinase AN) decreased most rutin content and antioxidant activity of asparagus juice.”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Pectinase AN reduced antioxidant activity in asparagus juice.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A pectolytic enzyme preparation from Aspergillus niger (pectinase AN) decreased most rutin content and antioxidant activity of asparagus juice.”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Pectinase AN oxidized guaiacol similarly with or without hydrogen peroxide.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the activity of pectinase AN to oxidize guaiacol had no significant difference with or without the presence of H2O2”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Pectinase AN contained laccase rather than peroxidase activity.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it was laccase activity, not peroxidase (PO) activity, that pectinase AN contained.”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
No polyphenol oxidase activity was detected in pectinase AN.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“We did not find any polyphenol oxidase (PPO) activity in pectinase AN.”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Heating pectinase AN lowered the rutin loss rate to 9% of unheated enzyme.
- Treatment
- heating at 70 degrees C for 1.5 mine0
- Outcome
- loss rate of rutine0
- Direction
- onlye0
- Value
- 9%e0
- Comparator
- unheated pectinase ANe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When most laccase activity of pectinase AN was inactivated after heating at 70 degrees C for 1.5 min and incubated with asparagus juice, the loss rate of rutin was only 9% of that treated with unheated pectinase AN”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Heating pectinase AN increased antioxidant activity of asparagus juice.
- Treatment
- heating at 70 degrees C for 1.5 mine0
- Outcome
- antioxidant activitye0
- Direction
- increasede0
- Comparator
- unheated pectinase ANe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When most laccase activity of pectinase AN was inactivated after heating at 70 degrees C for 1.5 min and incubated with asparagus juice, the loss rate of rutin was only 9% of that treated with unheated pectinase AN, and the antioxidant activity was even increased.”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Rhamnosidase activity was detected in pectinase AN.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Rhamnosidase activity was detected in pectinase AN”
t0“Enzyme-Catalyzed Change of Antioxidants Content and Antioxidant Activity of Asparagus Juice”
Claim · model-written summary
Rhamnosidase in pectinase AN converts rutin to quercetin-3-glucoside.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Rhamnosidase activity was detected in pectinase AN and can change rutin in asparagus juice to quercetin-3-glucoside, which has higher antioxidant activity than rutin.”
The same questions in other papers
heat · quality: phytochemicals · AsparagusPositive and negative results
1 in the opposite direction
- no effect
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.