1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) . 2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials, 3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold) 4. Let the mixture stand for 5 min 4. Add 1 mL of 7.5% (w/v) of sodium carbonate 5. mix. 6. Allow the solutions stand for 2 h at room temperature 7. Read the absorbance at 765 nm wavelength using spectrophotometer. 8. plot the standards curve of Gallic acid, use the equation to calculate your sample results 9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) . 2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials, 3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold) 4. Let the mixture stand for 5 min 4. Add 1 mL of 7.5% (w/v) of sodium carbonate 5. mix. 6. Allow the solutions stand for 2 h at room temperature 7. Read the absorbance at 765 nm wavelength using spectrophotometer. 8. plot the standards curve of Gallic acid, use the equation to calculate your sample results 9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) . 2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials, 3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold) 4. Let the mixture stand for 5 min 4. Add 1 mL of 7.5% (w/v) of sodium carbonate 5. mix. 6. Allow the solutions stand for 2 h at room temperature 7. Read the absorbance at 765 nm wavelength using spectrophotometer. 8. plot the standards curve of Gallic acid, use the equation to calculate your sample results 9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) . 2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials, 3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold) 4. Let the mixture stand for 5 min 4. Add 1 mL of 7.5% (w/v) of sodium carbonate 5. mix. 6. Allow the solutions stand for 2 h at room temperature 7. Read the absorbance at 765 nm wavelength using spectrophotometer. 8. plot the standards curve of Gallic acid, use the equation to calculate your sample results 9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
How do you mix water with methanol for DPPH control preparation.? If doing this many interferance will huppen . It could be better to use water with ABTS for water extract . In DPPH MeOH only must be used and in the same time can not be able to use MeOH with ABTS assay.
How do you mix water with methanol for DPPH control preparation.? If doing this many interferance will huppen . It could be better to use water with ABTS for water extract . In DPPH MeOH only must be used and in the same time can not be able to use MeOH with ABTS assay.
The total phenolic contents in all samples was calculated the using the formula: C = c V/m where, C = total phenolic content mg GAE/g dry extract, c = concentration of gallic acid obtained from calibration curve in mg/mL, V = volume of extract in ml, m = mass of extract in gram.
The total phenolic contents in all samples was calculated the using the formula: C = c V/m where, C = total phenolic content mg GAE/g dry extract, c = concentration of gallic acid obtained from calibration curve in mg/mL, V = volume of extract in ml, m = mass of extract in gram.
Hello everyone, I am trying to calculate the phenol amount using gallic acid as standard and i try to express the amount of phenols as mg GAE (Gallic Acid Equivalents) / gram sample. I did fount a lot information here on researchgate but need some specific help please! So i made a stock by using 0.05 g gallic acid / 50 mL (95%) Methanol. Then i made standards by diluting the stock. Then i took from every standard 40 µL and added (360 µL demiwater, 800 µL F-C reagens, 800 µL (7%) NaCO3) and finally i measured the absorbance at 765 nm to produce a trendline! I also did kinda the same with my samples: BUT I solved 2.0 gram of sample in 10 mL of (95%) MeOH. Then i took also 40 µL of this solution and added the same compounds with the same amount shown above and measured the absorbance. The calculated concentration of sample was 0.28 mg/mL Gallic acid using the trendline. So i want to know the concentration in mg GAE/g sample. I think I make mistakes with the dilution factors but i am not sure. I calculated 1.37 mg GAE/g? Thankyou very much u all!
Hello everyone, I am trying to calculate the phenol amount using gallic acid as standard and i try to express the amount of phenols as mg GAE (Gallic Acid Equivalents) / gram sample. I did fount a lot information here on researchgate but need some specific help please! So i made a stock by using 0.05 g gallic acid / 50 mL (95%) Methanol. Then i made standards by diluting the stock. Then i took from every standard 40 µL and added (360 µL demiwater, 800 µL F-C reagens, 800 µL (7%) NaCO3) and finally i measured the absorbance at 765 nm to produce a trendline! I also did kinda the same with my samples: BUT I solved 2.0 gram of sample in 10 mL of (95%) MeOH. Then i took also 40 µL of this solution and added the same compounds with the same amount shown above and measured the absorbance. The calculated concentration of sample was 0.28 mg/mL Gallic acid using the trendline. So i want to know the concentration in mg GAE/g sample. I think I make mistakes with the dilution factors but i am not sure. I calculated 1.37 mg GAE/g? Thankyou very much u all!
please tell me that are you taking initial dry weight of sample (dried plant powder)or extracts (after extracting with solvent what we obtained is taken as dry sample?) Please help me ASAP.
please tell me that are you taking initial dry weight of sample (dried plant powder)or extracts (after extracting with solvent what we obtained is taken as dry sample?) Please help me ASAP.
The total phenolic content can be calculated as natural compound (gallic acid) equivalent (GAE) by the following equation: T= C XV/M . T is the total phenolic content in mg·g–1 of the extracts as GAE, C is the concentration of gallic acid established from the calibration curve in mg·ml–1, V is the volume of the extract solution in ml and M is the weight of the extract in g. Gallic acid is used as a standard compound and the total phenols were expressed as mg/g gallic acid equivalent using the standard curve equation: y = 0.0061x + 0.0396, R2 = 0.9991, Where y is absorbance at 760 nm and x is total phenolic content in the different extracts. A control is prepared by mixing 0.5 ml distilled water and 2.5 ml 0.1 mM DPPH solution. The samples are shaken well and keep in dark for 30 minutes at room temperature. The absorbance is measured at 517 nm against the blank solution consisting 2.5 ml MeOH and 0.5 ml distilled water. The radical scavenging activity is expressed as the radical scavenging percentage using the equation where; AS = absorbance of sample solution, Ab= absorbance of blank and AC = absorbance of control % scavenging = (As-Ab/ Ac) X 100, IC50 value is the concentration of sample require to scavenge 50% of DPPH free radical and is calculated from the graph of radical scavenging activity against the concentration of extracts. Statistically, the correlation between antioxidant activity and total phenolic content is determined by plotting IC50 (µg/ml) against TPC (mg/g).
The total phenolic content can be calculated as natural compound (gallic acid) equivalent (GAE) by the following equation: T= C XV/M . T is the total phenolic content in mg·g–1 of the extracts as GAE, C is the concentration of gallic acid established from the calibration curve in mg·ml–1, V is the volume of the extract solution in ml and M is the weight of the extract in g. Gallic acid is used as a standard compound and the total phenols were expressed as mg/g gallic acid equivalent using the standard curve equation: y = 0.0061x + 0.0396, R2 = 0.9991, Where y is absorbance at 760 nm and x is total phenolic content in the different extracts. A control is prepared by mixing 0.5 ml distilled water and 2.5 ml 0.1 mM DPPH solution. The samples are shaken well and keep in dark for 30 minutes at room temperature. The absorbance is measured at 517 nm against the blank solution consisting 2.5 ml MeOH and 0.5 ml distilled water. The radical scavenging activity is expressed as the radical scavenging percentage using the equation where; AS = absorbance of sample solution, Ab= absorbance of blank and AC = absorbance of control % scavenging = (As-Ab/ Ac) X 100, IC50 value is the concentration of sample require to scavenge 50% of DPPH free radical and is calculated from the graph of radical scavenging activity against the concentration of extracts. Statistically, the correlation between antioxidant activity and total phenolic content is determined by plotting IC50 (µg/ml) against TPC (mg/g).
The total phenol content in the plant extracts is determined by the Folin-Ciocalteu method .
The total phenol content in the plant extracts is determined by the Folin-Ciocalteu method .
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Following
Following
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1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) .
2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials,
3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold)
4. Let the mixture stand for 5 min
4. Add 1 mL of 7.5% (w/v) of sodium carbonate
5. mix.
6. Allow the solutions stand for 2 h at room temperature
7. Read the absorbance at 765 nm wavelength using spectrophotometer.
8. plot the standards curve of Gallic acid, use the equation to calculate your sample results
9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) .
2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials,
3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold)
4. Let the mixture stand for 5 min
4. Add 1 mL of 7.5% (w/v) of sodium carbonate
5. mix.
6. Allow the solutions stand for 2 h at room temperature
7. Read the absorbance at 765 nm wavelength using spectrophotometer.
8. plot the standards curve of Gallic acid, use the equation to calculate your sample results
9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
More
VOTE
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) .
2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials,
3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold)
4. Let the mixture stand for 5 min
4. Add 1 mL of 7.5% (w/v) of sodium carbonate
5. mix.
6. Allow the solutions stand for 2 h at room temperature
7. Read the absorbance at 765 nm wavelength using spectrophotometer.
8. plot the standards curve of Gallic acid, use the equation to calculate your sample results
9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
1. Use Gallic acid as a standards (1 mg/mL, use it in serial dilutions) .
2. Place sample extract (0.1 mL), gallic acid (standard calibration), or extracting solvent in a separate 10 mL vials,
3. Add 0.4 mLwater and 0.5 mL diluted Folin–Ciocalteu reagent (10 fold)
4. Let the mixture stand for 5 min
4. Add 1 mL of 7.5% (w/v) of sodium carbonate
5. mix.
6. Allow the solutions stand for 2 h at room temperature
7. Read the absorbance at 765 nm wavelength using spectrophotometer.
8. plot the standards curve of Gallic acid, use the equation to calculate your sample results
9. express the results as gallic acid equivalents per 100 g of fresh/dry sample (mg GAE/100gof FW/DW).
More
VOTE
How do you mix water with methanol for DPPH control preparation.? If doing this many interferance will huppen .
It could be better to use water with ABTS for water extract .
In DPPH MeOH only must be used and in the same time can not be able to use MeOH with ABTS assay.
How do you mix water with methanol for DPPH control preparation.? If doing this many interferance will huppen .
It could be better to use water with ABTS for water extract .
In DPPH MeOH only must be used and in the same time can not be able to use MeOH with ABTS assay.
More
VOTE
The total phenolic contents in all samples was calculated the using the formula:
C = c V/m
where, C = total phenolic content mg GAE/g dry extract, c = concentration of gallic acid obtained from calibration curve in mg/mL, V = volume of extract in ml, m = mass of extract in gram.
The total phenolic contents in all samples was calculated the using the formula:
C = c V/m
where, C = total phenolic content mg GAE/g dry extract, c = concentration of gallic acid obtained from calibration curve in mg/mL, V = volume of extract in ml, m = mass of extract in gram.
More
VOTE
Hello everyone,
I am trying to calculate the phenol amount using gallic acid as standard and i try to express the amount of phenols as mg GAE (Gallic Acid Equivalents) / gram sample. I did fount a lot information here on researchgate but need some specific help please!
So i made a stock by using 0.05 g gallic acid / 50 mL (95%) Methanol.
Then i made standards by diluting the stock.
Then i took from every standard 40 µL and added (360 µL demiwater, 800 µL F-C reagens, 800 µL (7%) NaCO3) and finally i measured the absorbance at 765 nm to produce a trendline!
I also did kinda the same with my samples:
BUT I solved 2.0 gram of sample in 10 mL of (95%) MeOH.
Then i took also 40 µL of this solution and added the same compounds with the same amount shown above and measured the absorbance.
The calculated concentration of sample was 0.28 mg/mL Gallic acid using the trendline.
So i want to know the concentration in mg GAE/g sample.
I think I make mistakes with the dilution factors but i am not sure. I calculated 1.37 mg GAE/g?
Thankyou very much u all!
Hello everyone,
I am trying to calculate the phenol amount using gallic acid as standard and i try to express the amount of phenols as mg GAE (Gallic Acid Equivalents) / gram sample. I did fount a lot information here on researchgate but need some specific help please!
So i made a stock by using 0.05 g gallic acid / 50 mL (95%) Methanol.
Then i made standards by diluting the stock.
Then i took from every standard 40 µL and added (360 µL demiwater, 800 µL F-C reagens, 800 µL (7%) NaCO3) and finally i measured the absorbance at 765 nm to produce a trendline!
I also did kinda the same with my samples:
BUT I solved 2.0 gram of sample in 10 mL of (95%) MeOH.
Then i took also 40 µL of this solution and added the same compounds with the same amount shown above and measured the absorbance.
The calculated concentration of sample was 0.28 mg/mL Gallic acid using the trendline.
So i want to know the concentration in mg GAE/g sample.
I think I make mistakes with the dilution factors but i am not sure. I calculated 1.37 mg GAE/g?
Thankyou very much u all!
More
VOTE
The volume (V) used is it the total volume of the extract prepared or is it the pipetted volume used for finding the absorbance.
The volume (V) used is it the total volume of the extract prepared or is it the pipetted volume used for finding the absorbance.
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VOTE
please tell me that are you taking initial dry weight of sample (dried plant powder)or extracts (after extracting with solvent what we obtained is taken as dry sample?)
Please help me ASAP.
please tell me that are you taking initial dry weight of sample (dried plant powder)or extracts (after extracting with solvent what we obtained is taken as dry sample?)
Please help me ASAP.
More
VOTE
The total phenolic content can be calculated as natural compound (gallic acid) equivalent (GAE) by the following equation: T= C XV/M . T is the total phenolic content in mg·g–1 of the extracts as GAE, C is the concentration of gallic acid established from the calibration curve in mg·ml–1, V is the volume of the extract solution in ml and M is the weight of the extract in g. Gallic acid is used as a standard compound and the total phenols were expressed as mg/g gallic acid equivalent using the standard curve equation: y = 0.0061x + 0.0396, R2 = 0.9991, Where y is absorbance at 760 nm and x is total phenolic content in the different extracts.
A control is prepared by mixing 0.5 ml distilled water and 2.5 ml 0.1 mM DPPH solution. The samples are shaken well and keep in dark for 30 minutes at room temperature. The absorbance is measured at 517 nm against the blank solution
consisting 2.5 ml MeOH and 0.5 ml distilled water. The radical scavenging activity is expressed as the radical scavenging percentage using the equation where; AS
= absorbance of sample solution, Ab= absorbance of blank and AC = absorbance of control % scavenging = (As-Ab/ Ac) X 100, IC50 value is the concentration of sample require to scavenge 50% of DPPH free radical and is calculated from the graph of radical scavenging activity against the concentration of extracts. Statistically, the correlation between antioxidant activity and total phenolic content is determined by plotting IC50 (µg/ml) against TPC (mg/g).
The total phenolic content can be calculated as natural compound (gallic acid) equivalent (GAE) by the following equation: T= C XV/M . T is the total phenolic content in mg·g–1 of the extracts as GAE, C is the concentration of gallic acid established from the calibration curve in mg·ml–1, V is the volume of the extract solution in ml and M is the weight of the extract in g. Gallic acid is used as a standard compound and the total phenols were expressed as mg/g gallic acid equivalent using the standard curve equation: y = 0.0061x + 0.0396, R2 = 0.9991, Where y is absorbance at 760 nm and x is total phenolic content in the different extracts.
A control is prepared by mixing 0.5 ml distilled water and 2.5 ml 0.1 mM DPPH solution. The samples are shaken well and keep in dark for 30 minutes at room temperature. The absorbance is measured at 517 nm against the blank solution
consisting 2.5 ml MeOH and 0.5 ml distilled water. The radical scavenging activity is expressed as the radical scavenging percentage using the equation where; AS
= absorbance of sample solution, Ab= absorbance of blank and AC = absorbance of control % scavenging = (As-Ab/ Ac) X 100, IC50 value is the concentration of sample require to scavenge 50% of DPPH free radical and is calculated from the graph of radical scavenging activity against the concentration of extracts. Statistically, the correlation between antioxidant activity and total phenolic content is determined by plotting IC50 (µg/ml) against TPC (mg/g).
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Hello, How to express to mg GAE/100g of dried sample? Could you show the equation?
Hello, How to express to mg GAE/100g of dried sample? Could you show the equation?
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VOTE