Solvent Extraction - Science topic

Low NaOH concentrations may be ineffective for metal stripping, while high concentrations can cause organic phase stratification, hindering multistage stripping. To resolve this, optimize NaOH concentration (e.g., 1–5 M) to balance stripping efficiency and phase stability. Incorporate a phase modifier like ethanol or isopropanol to maintain homogeneity. Adjust temperature or stripping conditions to enhance metal transfer without destabilizing the system. If necessary, modify the extractant composition or add a surfactant to improve phase compatibility.

Here are some recent studies and reviews from 2023 onwards that provide detailed protocols and insights into the recycling of ionic liquids, that may help you:

thank you

Kex (extraction coefficient) measures the distribution of a solute between two immiscible liquid phases during solvent extraction, while Kd (distribution coefficient) quantifies the ratio of solute concentration adsorbed onto a solid phase to that in the liquid phase at equilibrium. Thus, Kex focuses on liquid-liquid interactions, whereas Kd pertains to solid-liquid interactions.

you can deploy Copilot Here are some reliable articles that focus on the selective separation of calcium (Ca) from magnesium (Mg) using solvent extraction techniques:

1. **[Method for selectively separating calcium and magnesium from a solution](https://patents.google.com/patent/WO2013042897A2/en)**:

- This article details a method for selectively separating calcium from magnesium in a solution containing both ions. The process involves using specific pH conditions to precipitate calcium as calcium oxalate while leaving magnesium in the solution. This method ensures that calcium is selectively removed without affecting magnesium.

2. **[Separation of calcium and magnesium using dual precipitation/chelation scheme](https://www.deswater.com/DWT_abstracts/vol_57_48-49/57_48-49_2016_22818.pdf)**:

- This study presents a process for the selective separation of calcium and magnesium from saline solutions. The method involves two stages of precipitation: the first stage uses sodium carbonate to precipitate calcium, and the second stage uses sodium hydroxide to precipitate magnesium. The process achieves high selectivity for calcium removal.

These articles should provide you with detailed information on the selective separation of calcium from magnesium using solvent extraction techniques.

### Ion Exchange Techniques for Separating Calcium and Magnesium

Ion exchange is another effective method for separating these two elements. Here are some techniques and resins you might find useful:

1. **Strong Acid Cation (SAC) Resins**:

- **Example**: Sulfonated polystyrene resins.

- **Usage**: These resins are great for removing calcium and magnesium ions from solutions.

- **Process**: The solution passes through a column packed with SAC resin, which exchanges the calcium and magnesium ions with hydrogen ions.

2. **Weak Acid Cation (WAC) Resins**:

- **Example**: Acrylic-based resins.

- **Usage**: These are particularly effective in acidic conditions and can be used to separate calcium and magnesium.

- **Process**: Similar to SAC resins, but WAC resins are more selective and can be used in a wider range of pH conditions.

3. **Ion-Exchange Chromatography**:

- **Example**: Using a sulfonated macroporous resin.

- **Process**: The solution is passed through a column containing the resin. Calcium and magnesium ions are separated based on their different affinities to the resin. The eluent, such as 1 M ammonium chloride or 0.03 M ethylenediammonium chloride, helps in the separation process.

For more detailed information, you can check out this article: **[Ion-exchange separation and determination of calcium and magnesium](https://www.osti.gov/biblio/7084186)**. It provides a comprehensive overview of the ion-exchange process and the types of resins used.

These techniques should give you a good starting point for separating calcium and magnesium.

Here are some ion exchange resins that are specifically suitable for selectively separating calcium (Ca) from magnesium (Mg):

### 1. **Purolite® C104**

- **Type**: Weak Acid Cation (WAC) Resin

- **Producer**: Purolite

- **Description**: This resin is effective in acidic conditions and has a higher affinity for calcium ions compared to magnesium ions, making it suitable for selective separation.

- **Applications**: Used in water softening and dealkalization processes where selective removal of calcium is required.

### 2. **Amberlite® IRC86**

- **Type**: Weak Acid Cation (WAC) Resin

- **Producer**: DuPont

- **Description**: This resin is designed for selective ion exchange and is particularly effective in separating calcium from magnesium in various solutions.

- **Applications**: Ideal for applications requiring selective calcium removal in high salinity environments.

### 3. **Lewatit® TP 207**

- **Type**: Specialty Resin

- **Producer**: LANXESS

- **Description**: This resin is tailored for selective ion exchange and can be used to target specific ions, including calcium, while allowing magnesium to pass through.

- **Applications**: Used in niche applications where precise ion separation is critical.

### 4. **Purolite® S930**

- **Type**: Specialty Resin

- **Producer**: Purolite

- **Description**: Designed for selective removal of specific ions, this resin can effectively separate calcium from magnesium in various industrial processes.

- **Applications**: Suitable for heavy metal removal and other selective ion exchange applications.

These resins are specifically designed to help you achieve selective separation of calcium from magnesium.

Good luck

Yes, you can use an oven with a low temperature to remove water from an aqueous extract.You’ll need to set the oven to a low temperature, typically between 50°C and 80°C (122°F to 176°F), depending on the sensitivity of the extract. Spread the aqueous extract in a shallow, heat-resistant dish or tray to increase the surface area, which helps speed up the evaporation process.

to recover and reuse isopropanol from a yeast extraction protocol using NaOH, the key steps would be:

1-Neutralize the NaOH if present in high concentration, such as by adding an acid like hydrochloric acid to form a salt that can be filtered out.

2- Break the azeotropic mixture of isopropanol and water, either by adding a salt or using a desiccant like molecular sieves to selectively absorb the water.

3- Distill off the purified isopropanol, potentially using fractional distillation to improve the separation, so it can be reused in future extractions. While complete recovery may not be possible, these techniques can help maximize the reuse of the isopropanol solvent.

Ahmed Kassem Khater

Only molecules that combine into molecular crystal lattices can be extracted with ethanol. Such molecules can have a size of up to 1-10 nm. For example, the size of a protein molecule is 4.3 nm. RF patent 2 140 287 uses alcohol extraction of albumin.

Usually, the first extraction can remove most impurities, while the second extraction further improves the purity of the target substance. By repeatedly extracting, the target substance can be effectively separated and impurities removed, resulting in a pure extract.

im still searchin for a simple method to get pure peracetic acid, but i use molecular seize 3A to reduce water and shift the reaction toward the formation of peracetic acid, also using highly purified hydrogen peroxide will help to get peracetic acid up to 40%, that's what i get, if this will help you.

Heptane may lead to phase separation; if so, toluene might perform better. You can distill out the toluene-acetic acid azeotrope, then add water and distill out the toluene-water azeotrope. That should leave you with just water as the solvent.

This method uses chromogenic reagents to react with heavy metals, forming coloured complexes that can be measured spectrophotometrically. For example, 1,5-diphenylcarbazide (Cr(VI) ) and isobutyl ketone (MIBK) are used for extracting metals like copper, zinc, and cadmium.

Dear He Li please do recommend my answer

Hydrophobic deep eutectic solvents (DES) are often used for extraction under alkaline conditions for several reasons:

1. **Selective Extraction:**

- Hydrophobic DES can selectively extract hydrophobic compounds from aqueous solutions. In alkaline conditions, certain compounds may become more soluble or undergo structural changes that make them more amenable to extraction by hydrophobic solvents.

2. **Enhanced Solubility:**

- Alkaline conditions can alter the solubility of specific compounds, making them more soluble in hydrophobic solvents. This is particularly relevant for compounds that exhibit increased solubility at higher pH levels.

3. **Stabilization of Hydrophobic Species:**

- Hydrophobic DES can stabilize certain hydrophobic species, preventing their reactivity or degradation under alkaline conditions. This stability allows for efficient and selective extraction.

4. **Improved Partitioning:**

- Alkaline conditions may alter the partitioning behavior of compounds, favoring their migration into hydrophobic environments. Hydrophobic DES provide such an environment, facilitating the extraction of target compounds.

5. **Tailored Solvent Properties:**

- Hydrophobic DES can be designed with specific properties tailored for the extraction of hydrophobic compounds. The composition of the DES can be adjusted to optimize its performance under alkaline conditions.

6. **Reduced Emulsion Formation:**

- Hydrophobic solvents are less prone to form emulsions when extracting from aqueous solutions, simplifying the separation of the extracted compounds.

7. **Biocompatibility and Green Chemistry:**

- Many hydrophobic DES are derived from natural compounds and are considered environmentally friendly. Their use aligns with principles of green chemistry, and they may be more biocompatible than traditional organic solvents.

8. **Application in Specific Processes:**

- Certain extraction processes or applications may require alkaline conditions due to the nature of the target compounds or the overall chemical process. Hydrophobic DES can be tailored to suit these specific requirements.

9. **Versatility and Tunability:**

- Hydrophobic DES can be designed with a wide range of structures and properties, allowing for versatility and tunability in their application to different extraction scenarios under alkaline conditions.

In summary, the use of hydrophobic deep eutectic solvents for extraction under alkaline conditions is driven by their ability to selectively extract hydrophobic compounds, enhanced solubility of specific species, stability under alkaline conditions, and their overall versatility and tunability for tailored applications. These solvents offer a promising and environmentally friendly alternative for extraction processes in various industries.

Dear Kashif Ali Please do recommend my answer if helpful

Solvent extraction can be a useful technique for purifying nitrogen-doped carbon quantum dots. Here's a general procedure you can follow:

**Materials Needed:**

1. Nitrogen-doped carbon quantum dots solution

2. Solvent (e.g., ethanol, acetone, or a suitable organic solvent)

3. Centrifuge

4. Filtration setup (e.g., syringe filter or filter paper)

5. Vacuum pump (if using a filtration setup)

6. Glassware and lab equipment

**Procedure:**

1. **Prepare Nitrogen-Doped Carbon Quantum Dots Solution:**

- Start with a solution of nitrogen-doped carbon quantum dots that may contain impurities or unreacted precursors.

2. **Selection of Solvent:**

- Choose a solvent that is suitable for extracting impurities or unreacted precursors while maintaining the stability of nitrogen-doped carbon quantum dots. Common solvents include ethanol or acetone.

3. **Extraction:**

- Mix the nitrogen-doped carbon quantum dots solution with the selected solvent. The impurities may preferentially dissolve in the solvent while the quantum dots remain in the solution.

4. **Centrifugation:**

- Centrifuge the mixture at a high speed to separate the impurities in the solvent from the quantum dots. The centrifugation time and speed depend on the specific characteristics of your solution.

5. **Decanting or Removing Supernatant:**

- Carefully decant or remove the supernatant (top layer) containing the dissolved impurities. Be cautious not to disturb the quantum dots pellet at the bottom.

6. **Washing (Optional):**

- Wash the quantum dots pellet with fresh solvent to remove any remaining impurities. Repeat the centrifugation and decanting process.

7. **Filtration:**

- If needed, filter the quantum dots solution using a syringe filter or filter paper to further remove smaller impurities or aggregates. Apply vacuum filtration if using filter paper.

8. **Characterization:**

- Characterize the purified nitrogen-doped carbon quantum dots using analytical techniques such as UV-Vis spectroscopy, fluorescence spectroscopy, or other characterization methods to confirm their purity and properties.

9. **Storage:**

- Store the purified nitrogen-doped carbon quantum dots in a suitable container, protecting them from light and contaminants.

**Notes:**

- Adjust the solvent choice and extraction conditions based on the properties of your nitrogen-doped carbon quantum dots.

- Use high-purity solvents to avoid introducing additional impurities.

- The purification process may need optimization based on the specific characteristics of your quantum dots and the impurities present.

Always follow safety guidelines and use appropriate protective equipment when working with chemicals and laboratory equipment. This procedure provides a general guideline, and you may need to adapt it based on your specific experimental conditions and requirements.

Yes, it can be done. You just have to make sure that the concentration of your extracting agent is high enough to obtain a good yield.

I would try a low speed centrifugation: the lipids should then coalesce into one layer, above the water, and can be removed by suction.

If you perform your SEC purification with organic solvents as eluent, I prefer to use Sephadex LH-20. This resin can withstand efficiently with organic solvents from my own experience.

There are other ways to analyze the organic phase for copper content after the stripping process. Some alternative methods are:

Yes, amino acids such as glycine and alanine can be extracted from aqueous solvents by organic solvent extraction. This is a technique that uses the difference in solubility and polarity of the amino acids and other compounds in the aqueous solution. The amino acids can be converted into their zwitterionic form by adjusting the pH of the solution to their isoelectric point, which is around 6 for both glycine and alanine1. This makes them less soluble in water and more soluble in organic solvents, such as chloroform, ether, or ethyl acetate2. The organic solvent can then be separated from the aqueous layer by using a separatory funnel or a centrifuge. The amino acids can be recovered from the organic layer by evaporating the solvent or by adding another aqueous solution with a different pH to reverse the extraction process3.

Some references that describe this method in more detail are:

Good luck

One software that can simulate solvent extraction process and measure the effect of parameters such as pH, O/A ratio, etc. is ChemCAD.

Suggested reference: D.A. Ellis, "Prediction of multistage solvent extraction operation from limited data", Industrial and Engineering Chemistry, 52(3) March 1960, 251-252.

On application of McCabe-Thiele (graphical) method to extraction mass-transfer problems at liquid-liquid extraction: https://www.researchgate.net/post/How_to_construct_McCabe_Thiele_diagram_for_LLE_and_is_there_any_software_for_LLE_simulation

For a related question at this forum you may check: https://www.researchgate.net/post/Can_anyone_help_with_Keratin_dissolution

Dear Saryu,

Tuberose (Polianthes tuberosa) is a delicate flower commonly used to extract essential oil through solvent extraction. The most suitable solvent for extracting tuberose oil is hexane, a hydrocarbon solvent that can remove a high yield of essential oil from flowers.

The procedure for extracting essential oil from tuberose flowers is as follows:

It's worth noting that the procedure may vary depending on the lab and equipment available. The quality of the oil and the yield may also vary based on the flowers' maturity and the extraction method. It's recommended to consult with experts in essential oil extraction to ensure the best possible outcome and to follow safety measures when handling solvents.

I hope this explanation was helpful,

Edgar M Cambaza

Regards

We did air filter spiking in this study and measured recoveries for method validation. You may find useful information in the methodology section, good luck:

Check https://pubs.rsc.org/en/content/articlelanding/2020/ra/d0ra04953k

Dear Rick,

that's an interesting technical question. According to the following article both Soxhlet extraction and ultrasonic extraction are possible:

Fortunately this useful paper has been posted by the authors as public full text on RG. Thus you can freely download it as pdf file.

Good luck with your work!

Hello Hojat,

sorry to see that your interesting technical question has not yet received any qualified answers. I must admit that as an inorganic chemist I'm not a proven expert in this discipline. However, I can suggest to you the following useful review article which could provide you with some initial ideas:

This article is accessible as public full text on RG. Thus you can freely download it as pdf file.

Please also have a look at the following interesting link which shows that shiitake mushroom extract and lentinan are indeed beneficial to the skin:

Good luck with your work!

Hi: I hear questions similar to yours every week from investigators. There are no single or simple answers to your questions. You are hearing "mixed answers" to your questions, because of a profound level of missing information needed to make constructive suggestions. A 'universal' extraction method will not be sample specific (often leaving behind actual sample or even changing or degrading it). None exist. There is no "single" analytical method which is applicable to the range of compounds you list (and please keep in mind that to detect and measure such compounds, they will always be in mixtures with many other chemical compounds too, perhaps hundreds or thousands). There is no "best" solution to use for LC-MS analysis as to make the detector useful, one first has to develop a high quality, sample specific, HPLC method for use (millions of possible methods. Experience and experimentation helps an expert narrow down the choices).

Pick one, then research what types of other materials may also be found in the same sample which need to be extracted and/or resolved from. Get an idea of how much material (concentration) might be expected. Determine what solvents these compounds are soluble in and under what conditions they may become unstable.

*Your teachers are in the best position to help you. Ask them to help you simply the project and also get help from experienced scientists. Focus on how you can specify detailed goals and then manage the process of finding the answers. 'We' do not need to do all of the work ourselves (critical to learn as a student). Where possible, hire or utilize other experts to work on the parts of the project that you do not have a decade of extra time to study. To develop just a basic level of proficiency in using HPLC and/or developing methods takes a minimum of five years (emphasis on "basic" level, as in after 5 years you will NOT have enough experience to develop reliable methods). HPLC coupled to MS (a quad or Orbitrap) requires far more hands-on training and industrial experience. Save time by finding local experts with industrial experience in using these techniques for the sample types YOU are most interested in. Make sure the proposed techniques really are 'best' for your research. HPLC and LC-MS may not be the right tools. This way you can spend your time collecting and researching samples and the analytical experts can work out the details needed to extract and measure the compounds.

Thanks Alan, I have already done the experiments in separatory funnels. Now I want to do it in continuous mode. So I need a to make a simple mixer-settler system.

I have already seen the koch modular column but as i said I want to make a mixer-settler.

The solution has Zn-Mn (40-15 g/L) and the solvent is DEHPA (diluted in kerosene).

Dear Juhaer, thank you for this interesting technical question. In general it should present no problem if you use an oil sample which contains traces of water. For more information see e.g. the following potentially useful link:

However, it's rather easy to remove the traces of water from your sample. For example, dilute the sample with 5-10 times its volume of diethyl ether and then dry the solution over anhydrous sodium or magnesium sulfate. Next day filter off the drying agent, was it twice with diethyl ether, and then evaporate the combined filtrates using a rotary evaporator. This should give you the water-free sample.

Good luck and best wishes, Frank Edelmann

We don't know until you do the experiment yourself.

Dear Widad Nafid thank you for asking this interesting technical question. Please have a look at the following potentially useful RG link which might help you in your analysis:

This article has been posted as public full text on RG. Thus it can be freely downloaded as public full text.

What makes me wondering about this article is that the authors used n-hexane because of its "very low value of toxicity". This is certainly not quite true. n-Hexane is significantly toxic and should not be used for processing foods.

Good luck with your work! 👍

Soo Yew Hang Replacing the water with a different liquid will change the pH. Indeed, there will be no pH since there will not be any H+ ions.

Both the centrifugation and filtration options have benefits and disadvantaged. Both require some investigation to optimize the process.

For centrifugation, any surfactants etc that are not attached to the particles will be removed. With filtration, the size of the filter pores and the molecular weight of the surfactants will determine how much, if any, is removed. Simple surfactants are likely to pass through the filter whereas very large polymer surfactants may be retained.

Whether or not centrifugation results in aggregated particles depends on how they are stabilized and other factors such as how big the particles are, their density and how long you centrifuge for.

It is likely that drying will lead to some irreversible aggregation. However, it will remove more water than the centrifugation option. You need to assess the maximum water concentration you can tolerate. If it is, say, 1%, then a few centrifugation/redispersion cycles may work well. If it has to be less than 0.1%, drying may be needed.

Of course, practically, the filter + drying is easier and quicker. Depending on how small and dense your particles are, an appropriate centrifuge could be expensive.

Nguyen Binh, On what basis do you think that the lines illustarated above should be straight lines? The maxima on the desorption efficiency vs C line are also incomprehensible. Moreover, in order to make the problem clearer, it is worth specifying how desorption efficiency was defined. Usually the value of "efficiency" does not exceed 100% (1), but it depends on how this value was defined.

Dear Jerry Nwabasa many thanks for your interesting technical question. Please have a look at the following potentially useful article which could help answering your question:

Also please see this relevant article:

This article is freely available as public full ext on ResearchGate

Hi Arini,

Are you sure you will be able to go over this book and be ready for the exam in one week?

Good luck

Rafal

Hello

could@@@@ u please send me the simulation file on aspen plus of the design of an extractive distillation or a tutorial related to this subject thx

I have attached two articles. I hope they woul be useful.

Kindly check https://www.researchgate.net/publication/330791415_292_The_Effect_of_Darkness_and_Sucrose_Concentrations_on_the_Production_of_Rosmarinic_Acid_in_the_Callus_of_Five_Rosemary_Genotypes

Hi Chinaza.

Thank you for your contributions, but I am looking for an organic solvent that is suitable for extracting arsenic trichloride from an aqueous solution. Chloroform or benzene is used in the paper mentioned above but these have health risks. I am looking for a safer organic solvent.

Regards

Yes we can apply ionic liquids to extract lipids. but we have to design the IL based on their polarity. as to me non polar ILs (less polar) mixed with organic solvetnts are better for lipid extraction than polar ILs. see this paper

The most used methol is HPLC with an analysis time of 15 min.

For each family of dyes, there are specific solvents according to their chemical structures (see Color Index)

how to adding volume amount in the formula which is used to dilute the extrat sample after HPLC analysis. (@ David Van Meter )

thanks.

Congratulations! Focus on objective always bring towards success.

Hi;

Instead, I propose you a new extraction technology: microwave assisted, solvent-free, based on the combined use of pressure, temperature and microwave irradiation.

With my best regards

Hello, For my part, a technical and economic study must first be realized. solvent extraction for uranium ore is only one step in its recovery. the product of the leaching and drying (yellow cake) must still undergo an electrometallurgical treatment in order to enrich it. For the question of economic profitability, the leaching recovery rate should be, after experimentation, the basis for judging whether the method is profitable in relation to the price of the "yellow cake". the most important thing is to know the price of leaching and the product and the adequate recovery rate.

crude extract by 70% ethanol

Dear Mr. Mamaqani. I definitely agree that solvent extraction for removal of drilling contaminations will certainly affect pyrolysis parameters like S1 (free hydrocarbons) and S2 (pyrolyzable hydrocarbons. NO doubt.

Therefore in my question and quest I specifically mentioned vitrinite reflectance and pyrolysis Tmax. So we are investigating the possibility of solvent extraction on maturity determination.

In fact what I started to think about effect of solvent on kerogen is somehow similar to coal swelling when exposed to particular solvents. Prolonged solvent extraction may lead to sorption of the solvent by the macromolecular network of the kerogen which is a entangled structure. If the solvent is sorbed into this structure then it cannot be removed by simple oven-heating of the solven-extracted powder. It follows then that this phenomenon will lead to serious effects on maturity determinations by geochemical or optical means.

Please look at the following below links which may help you in your analysis:

Thanks

Did you solve this problem? Which solvent you used at last? Karin Tal

In a crude extract use

1. n- Hexane to remove non polar compounds

2. Chloroform to remove all pigments

3. Ethyl acetate for the bio-active compounds

4. n-Butanol for hydrocarbons

Start from non-solvent ,hexane or petroleum ether 60-80 oC to separate the non- polar compounds oils and fats( fatty acids, essential oils and some sterols) , it is called defatting. Then use more polar solvent , ethyl acetate then methanol, 80% methanol and finally water.

Check the components for each fraction by TLC, separate the single compounds by MPLC ( Flash chromatograghy)

Identify the single comp. spectroscopically.

Test their desired biological activities.

Vacuum drying and freeze drying would work well. However, freeze drying is an expensive and time consuming method.

Vacuum drying is one of the the ideal methods for drying materials sensitive to heat or oxygen due to the advantage of drying at low temperature and minimizing the possibility of oxidation reactions. Since you are working with bioactives you will have to be careful with the temperature you select.

Gas Chromatography with an internal standard or coupled to a (Tandem) Mass Spectrometer is commonly employed, although the acetic acid might damage your column.

HPLC or LC-MS are also possible, using an 8% cross-linked sulfonated polystyrene cation exchanger and an ethanol gradient mobile phase.

Capillary Electrophoresis (CE) with UV detection would work, if the sample concentrations are within the LOD of the instrument. You can calculate it from the following literature values:

Acetic Acid (pH~7)

λmax: 200nm

Amax: 0.670

Ɛmax: 67

(McConnell et al.)

If you're really hard-up, you can titrate 0.1N NaOH in conjunction with a pH meter, and calculate the concentration based on the inflection point (assuming HOAc is the only acid in your extract).

For a decent sampling of methods you can check out PubChem: https://pubchem.ncbi.nlm.nih.gov/compound/176#section=Analytic-Laboratory-Methods

Please see attach.

Best Regard.

Lett Appl Microbiol. 2009 Jun;48(6):705-11. doi: 10.1111/j.1472-765X.2009.02599.x. Epub 2009 Mar 30.

Vinale F1, Ghisalberti EL, Sivasithamparam K, Marra R, Ritieni A, Ferracane R, Woo S, Lorito M.

Author information

Strains of Trichoderma spp. produce numerous bioactive secondary metabolites. The in vitro production and antibiotic activities of the major compounds synthesized by Trichoderma harzianum strains T22 and T39 against Leptosphaeria maculans, Phytophthora cinnamomi and Botrytis cinerea were evaluated. Moreover, the eliciting effect of viable or nonviable biomasses of Rhizoctonia solani, Pythium ultimum or B. cinerea on the in vitro production of these metabolites was also investigated.

T22azaphilone, 1-hydroxy-3-methyl-anthraquinone, 1,8-dihydroxy-3-methyl-anthraquinone, T39butenolide, harzianolide, harzianopyridone were purified, characterized and used as standards. In antifungal assays, T22azaphilone and harzianopyridone inhibited the growth of the pathogens tested even at low doses (1-10 microg per plug), while high concentrations of T39butenolide and harzianolide were needed (>100 microg per plug) for inhibition. The in vitro accumulation of these metabolites was quantified by LC/MS. T22azaphilone production was not enhanced by the presence of the tested pathogens, despite its antibiotic activity. On the other hand, the anthraquinones, which showed no pathogen inhibition, were stimulated by the presence of P. ultimum. The production of T39butenolide was significantly enhanced by co-cultivation with R. solani or B. cinerea. Similarly, viable and nonviable biomasses of R. solani or B. cinerea increased the accumulation of harzianopyridone. Finally, harzianolide was not detected in any of the interactions examined.

The secondary metabolites analysed in this study showed different levels of antibiotic activity. Their production in vitro varied in relation to: (i) the specific compound; (ii) the phytopathogen used for the elicitation; (iii) the viability of the elicitor; and (iv) the balance between elicited biosynthesis and biotransformation rates.

The use of cultures of phytopathogens to enhance yields of Trichoderma metabolites could improve the production and application of novel biopesticides and biofertilizers based on the active compounds instead of the living microbe. This could have a significant beneficial impact on the management of diseases in crop plants.

ach.

Extract your sample by using n-hexane or DCM. How ever, the volume of solvent depend with the amount of organic phase in your sample. Extract three or more times from the same sample for more yield. Then concentrate your extracts using rotary evaporator and filtered through syringe filters and inject to GC-MS.

Grzegorz Boczkaj Thank you for your kind interest. The temp of rotary evaporator is fixed at 40 °C with vacuum pressure of 120 psi. And H:EtOAc 6:4 solvent is the extracting solvent in florisil open column. The extracted pesticide is 5 ppm spiked Hexaconazole in acetonitrile.

But in LC-UVD peak, there is a visible unexpected solvent peak. How to reduce this unexpected peak of solvent?

Hi Fangyuan,

years ago we extracted natural substances from various biological sources, analyzed them with LC/MS and purified them (mg scale). Volatile substances were extracted e.g. with steam distillation. Otherwise, a Soxlhet extraction of solids was often carried out. Common solvents were methanol, ethanol, ethyl acetate, dichloromethane, diethyl ether, n-hexane. The extracts were then concentrated and first analyzed by LC/MS (TOF). The extracts were then fractionated and the fractions were then analyzed by 1H-NMR and C13-NMR. Unfortunately, the focus in our laboratory has shifted, i.e. we have not performed natural product analysis for years. Chemists do not like natural substances with many chiral centres.

Maybe this link will answer some of your questions:

Regards

Markus

If you just want to get secondary metabolites, then you will not necessarily liquid azod. Make it just not necessary to obstruct the work

Dear Rabia,

By answer on our request, you can use the spectral analysis approach using standardized spectro-colorimetry

Hi there. the calculation for each solvent extraction is as follow:

1st solvent yield={ (50-1.008)/50}X100. and the same thing repeat again for other solvent to calculate yield percentage. Cheers.

I believe yes, Amir hossein Aref it depends on what/which molecule you are considering. As for example if we consider weaker bonded CH3CL, in which C-Cl specifically. Then we can calculate the energy require to break this bond. Like for 9 debye the breaking energy lies near about 3.5eV.

So theoretically you can break these like weaker bonds using electric/magnetic force, And if you can build a machine which such capabilities you can also practically break these type of bonds.

Extract can be purified by following method, if it is prepared in water. First remove the fatty material by layer separation with n-hexan, then separate with 1-butanol, you will get your polyphenol/organic portion.

Grzegorz Boczkaj

Thank you Sir!

Have a look on Separation and Purification Reviews article. You should find one or more.

Thank you, Yuri and Detlef. I'll try your suggestions. Best regards!

In general, try to avoid halogenated solvents. They are typically more environmentally harmful and are often carcinogenic. You are quite right to want to replace ethylene dichloride. I am not familiar with your particular application but let me offer some advice about finding a replacement. You should consider a) boiling point, b) water miscibility, and c) solvatochromic parameters.

A. If the solvent must be refluxed during the procedure (either during a synthesis or a Soxhlet extraction) then the replacement solvent should have a similar boiling point. Otherwise the bp is not so important.

B. If you're using the solvent to extract products from water, then the solvent must not be water-miscible. If you aren't using water, then acetonitrile might be a good replacement for ethylene dichloride.

C. Solvatochromic parameters measure solvent properties such as acidity, basicity, and polarity. I recommend using the Kamlet Taft parameters. The acidity (alpha) value of ethylene dichloride is 0. Its basicity (beta) value is also zero. But its polarity is quite high (pi star value of 0.81). Therefore you should seek a solvent that has very low alpha and beta values but a very high pi star value. Unfortunately, nonhalogenated solvents of this type are very rare (see Green Chem., 2012, 14, 1245) but I suggest that you try toluene, anisole, or even ethyl acetate. Ethyl acetate might not be polar enough, while toluene and anisole have rather high bp.

Usually the membranes prepared immersing in the final water bath for a period of 2-3 days, with daily change of water, so as to ensure thorough removal of residual solvent and additives prior to final membrane drying.So I suppose that you are used alcohol instead of water this is depending on the type of solvent that used in the membranes preparation.

Organic solvents should be avoided.

But in order to use the appropriate solvent it is necessary to know the target phytocompounds.

it depends on your analytes if they are polar, you need stronger eluent (higher polarity).

For me DCM is slightly polar - you can try it with and without metanol addition.

regards,

G

in the extraction of dyes metabolites after bacterial degradation present in organic or aqueous layer for FTIR analysis?

the color of dyes present in aqueous extract

Methanol

You can use the same solvents in both your experiments and TLC.

Recommended mobile phases:

-DCM-MeOH (40:1, 30:1, 20:1, 10:1, 5:1)

-EtOAc-petroleum (3:1, 2:1, 1:1, 1:2, 1:3)

According to the retention factor of your samples, you will be able to decide which mobile phase suits you best.

Regards

I am not sure whether your question concerns the solubility of zinc sulfate in water, but ZnSO4.7H2O is very soluble in water under neutral or acidic conditions (> 50 g/100 mL at room temperature). Solubility does increase with temperatures, e.g. > 100 g/100 mL at 70°C. Can you describe your problem in more detail?

I had use this clean-up procedure for hexane:DCM extracts from soil samples:

The extracts clean-up apparatus was built from a glass column (1.5 cm ID and 40 cm height) packed from the top; 2g florisll (200 mesh), followed by 2 g of anhydrous Na2SO4, and 2 g of activated silica gel (60-200 µml).

Dear Sir,

Please have a look at this link.

Hello again Azlan.

You're probably using a centrifuge to separate your both "phases" of your solution and not a homogenizer.

A homogenizer would grind the bulk of your samples and allow the solvent to better extract your samples and should be done prior to submitting to MAE.

Best of luck,

Filipe

High oil or fat content can sometimes be detrimental to fermentation. But first of all, what do you mean by high fat or oil content? In some cases, certain microorganisms grow at high lipid contents because they are adapted to produce lipases, thereby allowing access to fatty acids. On the other hand, as mentioned by Mr Calt, a high content of oil in a fermenter can increase the viscosity of the system and consequently reduce the KLa negatively impacting the fermentation.