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Phenolic Compounds - Science topic

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I have stored my phenolic extract at different temperature 4 C and -20C It shows that its activity decreased in -20C compared with the 4C
My question is the storage of phenolic compounds at low temperature -20C does affect their activity?
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I do not know the details, but in the case of extracts in solution (water or organic solvents), crystallization may have occurred as the temperature decreased.
If crystals are re-diluted into solution, their solubility is often lower than that of the crude extract in the amorphous state, and thus their activity is assumed to be lower.
I recommend that you first conduct a stability evaluation of the typical compounds contained in the extract to see if changes are really occurring in the desired extract end product.
For example, in order to verify the stability, it is better to re-dissolve the product in a solvent with good solubility and evaluate whether the quantitative value has changed.
If there is no problem with the quantitative value, it would be better to try to dry the good solvent again to an amorphous state using an evaporator, etc.
Good luck!
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Hi everyone!
I´m currently working on solid state fermentation and I want to measure total phenolic compounds. However, some articles report a extraction using citrate buffer (pH 4.8-5.0) while others use methanol, ethanol or solvents combination to extract. Which one should I use and what is the difference in each case? I normally use methanol for doing my extractions but I don´t know if it´s the most reliable method after the fermentation. I´m working with agroindustrial byproducts
Any recommendations? Thank you very much :)
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Hydroalcoholic solvents are the best to use...phenolic acids diffuse to water, flavonlids prefer the organic such as ethanol...80_90% ethanol is worth to try...for ph issue, if you choose alkaline rougly saying 9 , 10 most of the phenolics come up as anion thus water solubility is increased... more acidic ph needs more organic percentage and higher alcohol compositio os needed due to the increased hydrophobicity of the target phenolics...
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In the measurement of phenolic compounds and antioxidant properties of Stevia, after mixing the ingredients according to the methods mentioned below, the color of the mixture becomes dark and cannot be read by the spectrophotometer. I diluted the mixture 10 times but it was still dark. Please help me out in this case.
Antioxidant: 40 microliter of extract solution (30%)+ 2.9 ml methanolic solution 0.1 mM of DPPH
Phenolic compounds: 1ml extract solution (30%) 1ml Folin-ciocalteu reagent (1:10) + 1ml sodium carbonate 35% + 2 ml distilled water
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My pleasure dear colleague, I wish you good luck in your experiments.
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I would like to extract terpenoids, alkaloids, and total phenolic compounds from a powder of dried plant material. What are the best protocols?
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Dear Hermine Boukeng Jatsa , the best way to achieve what you want is to do hydroalcoholic extraction from the plant material, you can use an extraction system such as Methanol-water (80:20), then prepare your extract for MPLC then prep-HPLC in order to fractionnate then purify compounds.
If you don't have prep-HPLC you can use the classical methods, following these steps:
1/ extract plant material with cyclohexane or heptane --> terpenoids
2/ then extract the residue with Methanol --> alkaloids + phenolic compounds
3/ recover the alkaloids using the acid extraction method (liquid/liquid extraction where the acidification of the aqueous phase make the alkaloids soluble on the organic one)
4/ you will obtain the alkaloids alone, the other phase will have the polyphenols and other polar to medium polar compounds.
best regards
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I am going to use the 4-aminoantibrin technic to measure the concentration of phenol compounds using a spectrophotometer.
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The answer depends on whether the concentration of NH3 or NH4Cl is specified. Once the ingredients are mixed the pH will be adjusted using HCl or NH3I suggest that solution.
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Dear experts
We have several full test methods for evaluating phenolic compounds and I am pretty sure that folin-ciocalteu (FC) method has been applied by many of us.
I'm looking for a standard protocol that explains step by step.
In one method just mentioned fc 1:5, another is 1:10 even I saw 1:1.
For some references, the alkaline agent is 29.5%, about 7% and about 5.5%.
The inoculation time also varies from 24 hours at room temperature to 30 minutes at 40 degrees Celsius.
No protocol exists for the standard solution, only the preparation of the solutions.
The volume of the samples, the different concentrations and the other agent are also different.
The absorbence is between 745 and 780.
Can I ask you to rely on your background and experience?
Regards
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Hello!!! This is an article that contains a standard protocol, explains step by step.
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I am working with Waters Xevo GS-2 Q-TOF mass spectrometer in MSe mode to analyze and identify phenolic compounds (mainly flavonoids) in a water/metanol extract. But, when i open my .raw files, every peak is represented as MS1. Where my MS2 peaks go? It is a way to fix this issue??
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3 years later, I am having the same problem (Waters Xevo G2-XS Q-TOF), please Daniel, could you tell me how figured up that problem?
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I have questions about the potential uses of Phenolic compounds/
1- Do you think Phenolic compounds can act as oxygen donors and enhance aerobic conditions
2- D you think it is possible to utilize phenolic compounds as a source of organic carbon?
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Hello,
I am using the folin-ciocalteu method in order to quantify the Total Phenolic content of a plant extract.
I am using 0.5 ml of my extract + 2.5 ml of F-C reagent (diluted 10 times) and 2.5 ml of Na2CO3 (7.5%).
My problem is that when I add the Na2CO3, the solution turns instantly to dark blue so when I read the absorbance on the spectrophotometer, it goes directly to 4 (the max).
I diluted my sample 100 times and still have the same problem.
Any suggestions ?
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In 2.5 mL Folin-Cioleauteu’s reagent (10 %) 500 μL of sample was dissolved and kept it for 2 min. Then added 2 mL of Na2CO3 (5 %) and volume was adjusted up to 10 mL with distilled water. After vigorous mixing, the solution was heated at
45 C for 15 min and was kept for cooling. After cooling, the absorbance was measured against the blank at 765 nm.
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It is rich in B vitamins, ascorbic acid and even contains chlorophyll which will degrade at high temperature. 
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I am also interested to know about this. How to preserve the color and quality of chlorophyll in wheat juice and preserve it for many days.
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Formaldehyde treatment is used to remove all those phenolic compounds while extracting the alginate from the brown seaweed. My purpose is to fabricate a biomaterial by merging the alginate that extracted from brown seaweed and the collagen that extracted from fish.
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Hi there CVD,
Would recommend that you first become familiar with the chemical reaction and then look for substitutes. Not as cheep. but it is possible to avoid using formalin.
Good luck
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Hello,
I have performed an in vitro anti-inflammatory activity analysis (BSA denaturation) of methanolic extracts of the leaves and stems of my plant. I found that the activity of the stems is significantly higher than that of the leaves. My question is:
- How can we explain this difference, namely that during the determination of phenolic compounds the leaves showed a higher content than that of the stems. and also for the antioxidant activity.
Can you help me please?
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The simple reason is that the phytochemicals responsible for the anti-inflammatory activity are more abundant in the stem, or the stem may contain secondary metabolites different from those contained in the Leaves. Different plant parts are known to contain different kinds or different proportion of phytochemicals. I will be necessary to isolate the compounds from both parts and study them
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Does the modeling of the matter transfer phenomenon with chemical reaction during solid liquid extraction of phenolic compounds require a chemical characterization of each point of extraction kinetics? In the case where the chemical characterization is impossible. Is it possible to make a modeling by supposing the reactions which take place? Do you have any documents to advise me? Thanks for your help
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You may benefit from toxchem model
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Hello. Do you think spontaneous formation of esters of phenolic compounds and fatty acids is likely, if all the necessary components and lipases are present in the medium, for example, when preparing food.
Sincerely, Timur.
Thanks for the answer.
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I would like to know the lignin degradation products in cocoa pod husks, after delignification.
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The method consists of evaluating the in vitro digestibility of phenolic compounds in fish diets, which will employ the species' own enzymatic extracts. Thank you for the information.
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Some authors are using a series of new alternative of ionic liquids, named DES and Ch-DES and claimed to overcome the disadvantages of conventional extraction methods. How these solvents overcome it? What are the main advantage and problems and issues related to these components for extraction of high value chemicals/ phenolic compound etc extraction from various bioresources ?
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The reason for the application of Choline chloride in DES as a replacement for ionic liquids is based on advantages such as ease of preparation, low cost of DES, environmental friendliness and ability to work at low temperatures to achieve similar results.
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If any one have any paper or idea about it ?
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The aim is to extract cyclic peptides, alkaloids, diaminoacids,
And at the same time get rid of the pigments and phenolic compounds
We tried with 80% MeOH in water, but still there are lots of pigments hiding our analytes.
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First, you should investigate what polarity the metabolites of your interest have and according to that, you will look for solvents that have a similar polarity. You can also base on the extract you already have and perform liquid-liquid extractions with immiscible solvents to eliminate the compounds you are not interested in.
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How may I idenntify some metabolites in a chromatogram of my plant extract (the HPLC technique was performed without standards).
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Which detector was coupled to your HPLC? Accordingly, you can rely on previous studies where they used a system similar to yours, and even if possible of the same plant species.
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Acid-base extraction is recommended for the separation of alkaloids from crude extracts. How to separate flavonoids or phenolic compounds from a crude extract?
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Dear AAntonio, this is a very interesting technical question which has been frequently discussed on RG. I also suggest that you directly search the "Publications" section of RG to find and access relevant publications on this topic. Fore example, please have a look at the following useful articles which have all been posted as public full texts on RG:
Isolation and Characterization of Novel Flavonoid from Methanolic Extract of Pongamia pinnata Pods
Article Isolation and Characterization of Novel Flavonoid from Metha...
Flavonoid from methanolic extract of Limoniastrum Feei (Girard) batt (Plumbaginaceae)
Article Flavonoid from methanolic extract of Limoniastrum Feei (Gira...
FLAVONOID FROM METHANOLIC EXTRACT OF LIMONIASTRUM FEEI (GIRARD) BATT (PLUMBAGINACEAE)
Article FLAVONOID FROM METHANOLIC EXTRACT OF LIMONIASTRUM FEEI (GIRA...
Isolation and Characterization of Flavonoid from Methanolic Extract of Mirabilis jalapa Linn. Tuber and Evaluation of its Cardioprotective Property
Article Isolation and Characterization of Flavonoid from Methanolic ...
Preliminary Phytochemical Screening and HPLC Analysis of Flavonoid From Methanolic Extract of Leaves of Annona squamosa
Article Preliminary Phytochemical Screening and HPLC Analysis of Fla...
and various others. Good luck with your research and best wishes!
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Raw sugar is generally golden brown-honey colored. The raw sugar is converted into white sugar using the refinery process, in which the raw sugar solution (melt) is treated with phosphoric acid (which reduces the color slightly), followed by the addition of lime (calcium hydroxide) to reach 7-7.5 pH and heated to 85 Deg Celcius generate calcium phosphate flocs, which reduces the color and turbidity of the solution. Flocculating agents (polymers) are also added to increase the flocculation rate. This process is called "phosphitation" in the Sugar industry and is able to reduce the color of the melt by upto 30-40% (the color is measured using the ICUMSA method). This requires around 400 ppm of phosphoric acid, which is a huge quantity considering the volume of melt treated in a refinery.
I want to know whether the same effect can be obtained by using any other chemicals/biochemicals in lower amounts?
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I have isolated the phenolic compounds from plant extracts. the compounds are soluble in DMSO and insoluble in most other solvents. I would like to get them analyzed in the MS for molecular weight determination because some have a long chain of CH2 (seen from the NMR data). I do not have much expertise on how and what solvent I can use for the process. Please may I get your opinion
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Thank you @Kobra Ghobad for your suggestion. But the sample looks to be insoluble in cold MeOH unless they are warmed to about 50 degrees, when left for a while they precipitate. This means there is a risk of killing the HPLC column.
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Hello, y'all. I have been searching for a metals database such as Cd or Ni to do computational analysis with the protein, while for the protein database I have been using https://www.rcsb.org/ but is there any database where I could get metals data as same like protein database. Your response would be appreciated. Thank you
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Hi Unays!
Not sure if I understood what you need. Are you studying metal-protein interactions? And if so, what are you interested in? Interaction? Function?
There is a good database (Brenda), where you can explore several enzymatic parameters, such as metal interactions. When I want to confirm my metal sites, for instance, I use CMM (Check my metal), which analyses coordination, occupancy, etc.
Not sure if that's related to what you need, but I hope this can help.
Best,
Lorenzo
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My Compound is Leaf powdered Methanolic extract which is showing good phenolic compounds upon dipping in FeCl3. -My problem is phenolic compounds are not eluting with any common solvent system.
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Maybe your target compound can be recrystallized.
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I am working with Amaranth accessions which are green to red in color and contain high phenolic compounds. Using the CTAB method with the slight modification I am trying to get high-quality DNA so that it can be used for SNP genotyping. So, please anyone can solve this problem? And help me to get high-quality DNA which is required for the SNP chip.
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Shantanu Das Can you write all the protocol steps? Then we can discuss.
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During the process of aqueous extraction of phenolic compounds, I got a mucilage that must be separated from the extract that I would like to study. Thank you for your help.
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You can precipitate the mucilage with ethanol at a low temperature, similar to the methodology of article
  • DOI:
  • 10.3390/ijms20215302
Specifically in this part:
The supernatant was again precipitated with the addition of cold absolute ethanol to a final concentration of 80% (v/v) and kept at 4 °C overnight. The resulting precipitation was vacuum concentrated and freeze dried, yielding Grifola frondosa heteropolysaccharide (GFP).
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Dear Scientists
I am trying to method validation of major phenolic compound from a medicinal plant. My standard curve recovery was an acceptable range (80 to 100%). But, when compound standards are spiking with extract after that recovery % is more than 200%. What types of solutions are needed to solve this problem? Please give me your valuable suggestions.
Thank you
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Dear Jinadasa
Thank you for your information. I will check and update you.
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hello
How to prepare a fruit juice sample to measure phenolic and antioxidant compounds by HPLC?
fot types of berries and grape?
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Fruit Juices may be extracted exhaustively by maceration with acidic methanol over 24 h at room temperature. The extract is filtered and concentrated in vacuo at 37C. The extract is partitioned sequentially with hexane and ethyl acetate, and the aqueous fraction containing phenolics may be lyophilized. Removal of other water-soluble constituents, such as sugars and ascorbic acid, is accomplished by column chromatography by applying the dried extract to a Diaion HP-20SS resin column and allowed to adsorb for 20 min. The column is sequentially eluted with 500 ml water to remove sugars etc. and then with 300 ml acidic methanol to elute all of the phenolic compounds (flavonoids/anthocyanins).
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Hi guys, may I ask for help to calculate phenolic content in my sample
Here's my step to do FC method:
- red pitaya peel 10 gram in 50 ml ethanol 50 % (and i got extract from here)
- i use 1,5 ml red pitaya peel extract + 2 ml folin ciocalteu + 2,5 ml Na2CO3 7,5 %
the absorbance is 0,714 with gallic acid curve is y=0,0131x + 0,0411
Thank you for your help
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Folin-Ciocalteu colorimetric method can be a useful and easy technique foe analizing TPC
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I usually feel difficulty to isolate the flavonoid glycosides or other phenolic compounds from n-butanol fraction. Which chromatographic technique is suitable for isolating polar compounds from the n-butanol fraction? Can anyone help me?
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Although it is a traditional method, I depend on the utilization of column chromatography. This is usually performed after establishing the solvent mixture by applying TLC.
All the best
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I am preparing CTAB buffer and I read that addition of PVP (Polyvinylpyrrolidone) helps to remove phenolic compounds. Most of the times in protocols there is no additional information about average molecular weight of used PVP, but I found in some, where it was specified that it was PVP 40 (mol wt 40 000) for DNA extraction. But I wanted to know if I can use the same for RNA extraction or should I use PVP 360 (mol wt 360 000)?
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PVP is basically a polymer, which will only mention as %. So its better to go with dilution. In my experience, CTAB-buffer with 2% PVP works well for the Isolation of DNA. Incubate your CTAB with PVP for 15 mins at 65 C and then vertex.
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Hi all,
I understand that quantification of total phenolic content (TPC) refers to all the phenolic compounds present in the sample of interest, however, the folin-ciocalteu assay does this by a redox reaction (all reducing substances). On the other hand, antioxidant capacity can be determined by DPPH assay in which the AO reduces the free radicals. What is the purpose of quantifying both TPC and AO capacity?
Are we quantifying both separately because not all phenolic compounds have antioxidant capacity?
*Please correct me if I am wrong.
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Dear Natasha,
The major plant compounds characterized by antioxidant activity are polyphenols. These are present in most plants and are considered to prevent free radicals associated damages in numerous ways including direct scavenging of free radicals and inhibition of enzymes involved in free radical production.
Whereas, TPC activity is the process to figure out the amount of phenolic content present in the samples. Phenolic compounds that contained in the plants have redox properties, and the properties allow them to act as antioxidants.
After checking antioxidant activity in the samples, We perform quantitative assay through total phenolic content, total flavonoid content, and total saponin content, etc. to check the total quantity of secondary metabolites present in the sample.
Regards,
Divya Jain
India
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During transformation it is a general practice to add some phenolic compound, generally acetosyringone, for the transcriptional activation of vir locus of Agrobacterium. How much time it is needed to full transcriptional activation of the vir genes after addition of acetosyringone?
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Since gallic acid has 4 hydrogens to reduce, 1 gallic acid is equivalent to 4 phenol, right?
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ESTIMATION of TOTAL PHENOLIC CONTENT
by FOLIN CIOCALTEU METHOD
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Is is possible that grape seed proteins binds polyphenols, which are not extractable? If so, how can we isolate polyphenols from the extract that might contain protein? I am thinking of dipping the extract in an alkali solution.
What do you say?
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Akleshwar Mathur thanks for sharing!
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Due to the variety of compounds present in garlic such as water- and lipid-soluble organosulfur compounds, phenolic compounds, notably allixin, saponins and selenium , garlic has many medicinal and nutritional value. but some of the processing methods subjected with heat may reduce the anti-oxidant values. i want o make sure which and which.
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Is there any published research looking at the effect of diet on the absorption of phenolic compounds such as resveratrol, caffeic acid, chlorogenic acid, tannins etc which generally display poor bioavailability?
For example, does someone on a vegetarian diet absorb these types of compounds more or less effectively than someone on a non-vegetarian diet? Do dairy products have a influence as they can affect gut mucosa?
Any relevant information would be greatly appreciated.
Thank you.
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There are some methods to synthesis phenolipids in the literature. However, there are many parameter differences such as solvent, amount of reactant and time. In your opinion, what is the best way to make phenolipids using fatty acid (or fatty alcohol) and phenolic acid?
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Dear Dr. Pierre Villeneuve,
Thank you so much. Your answer made me very pleased. So, what do you think about chemoenzymatic methods?
How can I understand if esterification has occurred?
What should I use as standard in chromatographic methods?
Please excuse me if I ask very basic questions. I'm a baby researcher yet.
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I am planing to extract total phenolic compounds from seeds of buckwheat. But I am confused that how much seeds are enough for the total phenolic compounds leading to the characterization of each phenolics. Please give me suggestion about the weight is required and which procedure I should prefer for extraction. If someone has supporting material please share it.
Thank You
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you can use 0.5 g and more
this enough
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Dear researcher,
I am extracting DNA from IV plants which contain a lot of phenolic compounds and secondary metabolites, due to which the DNA extracted always contains impurities (I tried several ways to remove them).
Please tell me the ways to either purify the DNA or such PCR conditions/programs which could amplify the DNA.
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I'm not sure the methods you have used for DNA purification, elaborating a bit would help us in finding a solution. I assume you're using phenol chloroform extractions? I can advise you to be very careful in not disturbing the aqueous-phenol interface when removing the aqueous phase. Don't be greedy, it's okay to leave some of the aqueous phase behind. If that doesn't work you can try commercial DNA purification columns, but I would advise trying the phenol chloroform extraction again as the DNA purification kits can be expensive. Even if the plant has lots of phenols they would be trapped in the organic phase and with proper centrifugation should not massively contaminate the aqueous phase. The problem with PCR is that your phenol contaminants can inhibit the reaction, so having pure DNA is essential for PCR.
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I am working with a phenolic compound whose standard is not available. What is the possibility of isolation if the structure is only available.
Thank you
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It is certainly possible and XIX century chemists proved it by extracting and purifying many natural compounds from plants!
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1. Is there polarity differences in Butanol Vs (methanol and ethanol)
2. How to perform solvent fractionation of plant extract by partitioning using different solvents (Butanol, chloroform, diethyl ether and water).
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Yes Polarity decreases down the group I.e methanol> ethanol>propanol>butanol etc...
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I have to take CD spectra of protein in presence of various phenolic compounds but they are showing there own intensity in 190- 240nm range. What should I take as control or blank to subtract?
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@mansi i did that but it didn't worked...
I'm attaching the picture.. Navy Blue is protein only.. Yellow and light blue are added compounds... The baseline for these is same concentration of compounds
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How can I calculate and express total phenolic content as mg GAE/g DE? Below are the details: 1. I dissolved 10mg dry extract in 1ml methanol 2. 200 micro was taken for folin ciocalteu assay 3. The absorbances for one sample were: (0.915, 0.917 & 0.919) 4. i used (0, 10, 30, 50, 70 & 90 micro g/ml) and got the equation (y = 0.0193x + 0.047)
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Dear Duried Alwazeer ,
If I dissolved (10) g of dried pomegranate peel with (25) ml of boiled distilled water to prepare aqueous extract of pomegranate peel, my question is how I can calculate the concentration of extract solution.
Thanks in advance.
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Is it possible in the plant extracts to have a total phenolic content lower than the total flavonoid content ? whereas many flavonoids are also phenolic compounds.
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are you mean phenolic compounds or phenol compounds.
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what is the best and simple way to derivatize phenolic compounds to fluorescent derivatives??
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Condensation of 2x1,3-diphenol with 1,2 di-benozic anhydride (Flourescein dye)and condensation of 2x 3-aminophenol with 1,2 di-benozic anhydride (Rhodamine dye)
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Hi everyone
I am using the LC-QToF-MS to identify the bioactive phenolic compounds of my plant samples, and I want to compare the relative concentration/abundance of individual phenolic compounds identified between my samples, and wondering can I use the MS precursor ion abundance to make such a comparison.
I only want to know the relative abundance and distribution of the identified phenolic compounds in my samples, not necessarily the actual concentration/quantification (since I only have a few standards).
Thank you so much
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If you have LC-MS data, I would suggest you try XCMS Online (https://xcmsonline.scripps.edu/) for relative quantification.
Here you can find an example of an application:
Hope it helps!
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Please I want to know if as a pyrone, Kojic can been be also classified as a phenolic compound?
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Both of them are not phenolic compounds they are heterocyclic compounds. Pyrone is heterocyclic chemical compounds, contains an unsaturated six-membered ring containing one oxygen atom and a ketone functional group while Kojic acid or5-Hydroxy-2-(hydroxymethyl)-4-pyrone or 2-Hydroxymethyl-5-hydroxy-γ-pyrone .
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I have tried following several protocols to extract DNA for PCR amplification (Lodhi et al. 1994; Doyle & Doyle1987), from Quercus leaves.  Interestingly, some samples showing good and clear band , however, other samples are not showing sharp band on my Agarose gel electrophoresis. Does anybody know what is the problem with my samples or which protocol to follow for good quality DNA isolation? I would very thank full for any comments and guidance
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attached a good article on pcr inhibitors. Not so good on modern dna purification methods but hopefully plant geneticists will give you the best preparation protocols
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I am working on analysis of some phenolic compounds via TLC scanning in fluorescence mode.
I noticed a decrease in peak areas upon increasing concentation in all used concentration ranges starting from nanogram/ml range to zeptogram/ml (10 -21) range in one of my compounds. Even in zepto range there are still peaks with large areas and decreasing areas upon increasing concentrations. I can’t establish linearity.
The other compound showing fluctuating readings up and down upon decreasing concentrations.
How to fix this problem and can TLC scanner in fluorescence mode reach single molecule detection or what is wrong?
I am using Camag TLC scanner
  • Mercury lamp
  • Excitation wavelength 230 nm
  • Silica gel 60 as stationary phase
  • K 320 as a filter
�
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yes I am using Camag TLC scanner 4 ,working on natural phenolic compounds and how degradation can affect readings if I am preparing fresh stock solutions every time and measuring readings instantly after developing plates and air drying the developing system (I also tried oven drying of eluent with the same problem).
I compared it with Agilent Cary eclipse spectroflorimeter, unfortunately it couldn't even detect concentrations in low nanogram range( TLC scanner is far more sensitive)
yes absorption mode gave the same behavior as florescence going up and down in the same way. how to avoid this problem???
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I prepare to test total phenolics content in the wine and then adopt different methods to extract total phenolic compounds. And then I will test total phenolic content in different extractions. However, the Folin-Ciocalteu's reaction is very sensitive to light. When I use UV-Vis to test absorbance of Folin-Ciocalteu's reaction. The repeatiability is terrible? So it is very difficult to know total phenolics content in wine or different extractions. How can solve? Could you give me some advise? Thank you very much
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Tobacco plants were subjected to 3 different nutritional treatments (A, B, C) for 3 weeks, and also were treated under two irrigation regimes during 2 weeks (Well-watered plants or Control plants, and Water deficit treated plants or drought plants). During drought plants treated with the treatments called "C" showed: (i) better water parameters, (ii) higher growth than control, (iii) higher water use efficiency and water saving, (iv) better recovery from extreme drought, etc.
Updated information:
  1. Model organism: Tobacco (Nicotiana tabacum L.)
  2. Pot size: 7.5 L pots (pot size 20 cm × 17 cm × 25 cm)
  3. Substrate: a mix of perlite:vermiculite (4:6)
  4. Treatments: Seeds were sown and two weeks later (15 days after sowing, DAS), seedlings were transplanted to 7.5 L pots. Then, plants were subjected to three different nutritional treatments. After 30 days (45 DAS), in addition to the three nutritional treatments, plants were also subjected to two irrigation treatments: optimal irrigation (control; CTR), in which pots containing tobacco plants were irrigated up to 100 % field capacity (3.5 mL g-1 substrate) throughout the experiment, and moderate sustained water deficit (WD), with pots irrigated every two days up to 60 % of field capacity (2.1 mL g-1 substrate) for 20 days (64-65 DAS).
Fresh biomass was collected in each treatment, and the following organic compounds were determined: MDA, H2O2, PROLINE, and PHENOLICS. Also, the PEROXISOME CATALASE activity was determined.
-Malonyl Dialdehyde (MDA) content, hydrogen peroxide content, and catalase activity are cellular oxidative stress biomarkers.
-Proline is a very important amino acid that which accumulation is correlated to plant stress tolerance
- Phenolics (phenolic compounds and flavonoids) are the largest group of phytochemicals that account for most of the antioxidant activity in plants.
In the attached figure there are the results of the ANOVA statistic in CTR or DROUGHT plants, and also is showing the logarithm with the base of 2 of the ratio between drought and control values to understand the decrease or increase in drought plants, in contrast, to control plants for each parameter.
What I see in this result is that there is no clear pattern related to a water deficit regarding the great results obtained in water parameters, plant biomass, water consumption/efficiency, photosynthetic activity, recovery from water stress deficit, etc.
To sum up there's complete nonsense in results in contrast to "C" treatment:
-No changes in MDA (reduction in the other nutritional treatments???????)
-Increase in CAT y H2O2???????
-a decrease in PROLINE????
-An increase in PHENOLIC compounds is logical due to the increase in H2O2, but it has no sense in plants that are more tolerant to drought.
I hope that someone might help me resolve this nonsense
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Hello J.D. Franco-Navarro
Your question can’t be answered as @Fahad Shafiq has correctly pointed out at the end of the comments because there is almost complete lack of information about the methods. The study seems to have been done with rather small plants, and in such a way that there would be a strong interaction between nutrition and water supply, making interpretation very difficult. Let us assume you grew the plants in soil, applied a liquid fertilizer and allowing some plants in each nutrient treatment to dry by stopping watering, while the control was given ample water. That is a standard molecular biology/biochemistry approach to such studies.
Which was the treatment supplying the most nutrients - A I suspect, with C supplying least. So plants in A would grow better than in C, and have more, larger leaves. When you started the drought treatment plants in A would dry the soil much faster than those in C – simply a matter of greater surface area in A. So plants in A would become severely drought stressed before those in C, which would appear to grow and be much more `drought resistant’. They would also have very different contents of metabolites. The lesson from this – if my supposition is true - is that it IS ESSENTIAL TO COMPARE PLANTS AT THE SAME RELATIVE WATER CONTENT. If this is not done then the study is invalid. I suggest my paper explains the problem and ways of doing such studies correctly – it focuses on GM plants but the problem is absolutely the same for all studies involving water supply.
Lawlor DW. Genetic engineering to improve plant performance under drought: physiological evaluation of achievements, limitations, and possibilities. J Exp Bot. 2013 Jan;64(1):83-108. doi: 10.1093/jxb/ers326. Epub 2012 Nov 16.
By ignoring the complexities involved with water supply in solid matrices and the effects of different rates of water loss, studies of the metabolism, genetic modifications etc are invalid. Hope this rather strong critic does not apply to your study. Please provide the necessary information about methods.
Best wishes
David
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Flavrnoids are subgroup of phenolic compounds. You must focus in the lecture to see if their any metabolic bathway consumed phenol content. Also make this test again to be sure about your results
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Please take a look at this useful RG link.
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Change in bioactive compounds pattern, thus the bioactivities could be different compared to the original substrate.
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@ S. Wenkart .. hey, Dear, I worked most about aromatic and phenolic compounds and biodegradations, but in new my research I was looking an effective method for prevention of occurrence of browning and reduce the effects of phenolics during micropropagations for obtaining higher efficiency...
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Answer maype here.
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You are welcome.
Just leave the ex-plants at room temperature without using any media for 2-3 days and then use for the experiments. This will dehydrate them and reduce the phenolics.
Note: It worked for me but differ from plant to plant. Try it on some explants.
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Hey all,
This is less of a question and more of a hint because I've been struggling with this for almost a year during my graduate career. In case you work with proteins and phenolic compounds you may run into some issues with Western blotting/chemiluminescence detection methods. Check out our paper here from 2017 if you have noticed similar problems. May save a lot of time, money, resources and frustration!
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I try
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Does Folin-Ciocalteu assay measure tannin content?
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I worked with Folin-Ciocalteu total phenolic determination. And, after that, I quantified the flavonoids totals and DPPH antioxidant assay, too. My friends that work with tannins performed the same. You can determine the percentage of flavonoids responsible for the antioxidant activity. Generally, when you have tannins in your sample, you will have flavonoids as well, due to the biosynthetic route. You can try to quantify the percentage of tannins in your sample using the HPLC-UV or UPLC/MS, is more accurate.
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Greetings!
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Hello everyone.I want to measure MDA and proline in Mentha piperita but i don't know which method is better for medicinal plant with phenolic compound?MDA assay with phosphate buffer or just with TBA and TCA.
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Dear Karami Moghadam,
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Hi
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Hello everybody
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Dear Andres Silva
In equation 47.6 x(100/(100-84.5), the 100 in numerator is not for conversion into 100 g dry basis. This 100 implies the 100% basis for dry mass basis. 307.09 mg is in one g of your sample on dry mass basis.
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Sharad Medhe Sir,
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Hello, Asma El Zerey-Belaskri!
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Polar solvents are frequently used for recovering polyphenols from plant matrices. The most suitable solvents are aqueous mixtures containing ethanol, methanol, acetone, and ethyl acetate. Ethanol has been known as a good solvent for polyphenol extraction and is safe for human consumption. However, as far as your question is concerned, methanol would be a better choice. Concentrations between 70 and 80% are regarded as appropriate. See the attached.
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Try using BioRender - (https://biorender.io/)
Is a free online app that contains a library of pre-made cells, proteins, membrane shapes, organs, lab equipment, etc. that you can drag-and-drop so you don't have to spend time drawing each element of the figure out yourself. Saves a lot of time for creating schematic figures, and the icons are all created by scientific illustrators so they're both beautiful and accurate! And it's free for educational use.