Etiket Arşivleri: Extraction

Turunçgil Kabuklarının Biyoaktif Bileşenleri ve Antioksidan Aktivitelerinin Belirlenmesi ( Melih GÜZEL )

Turunçgil Kabuklarının Biyoaktif Bileşenleri ve Antioksidan Aktivitelerinin Belirlenmesi

Melih GÜZEL  , Özlem AKPINAR

Öz

Meyve ve sebzelerde bulunan biyoaktif bileşenlere karşı ilgi, bu maddelerin insanları bazı hastalıklara karşı korumaya yardımcı olabilmesinden dolayı giderek artmaktadır. Bu kimyasalların, oksidatif stres sonucunda hücrelerde meydana gelen serbest radikal zararını azaltabildiği ve kanser, kardiyovasküler hastalık, obezite ve diğer hastalıklar gibi büyük kronik tabloların risklerini azaltması ile bağlantılı olduğu belirtilmektedir. Bu çalışmada turunçgil kabuklarının biyoaktif bileşenleri ve antioksidan özellikleri incelendi. Turunçgil kabukları limon (Citrus limon), portakal (Citrus sinensis), mandalina (Citrus reticulata) ve greyfurt (Citrus paradisi) meyvelerinden elde edildi. Toplam karotenoid, beta karoten, askorbik asit, antosiyanin, toplam fenolik ve flavonoid içerikleri ve toplam antioksidan aktiviteleri TEAC, FRAP ve DPPH metotlarına göre kolorimetrik yöntemler kullanılarak belirlendi. Mandalina kabuklarının karotenoid bileşikler, limon kabuklarının askorbik asit, greyfurt ve limon kabuklarının fenolik bileşikler açısından zengin olduğu ve mandalina ile portakal kabuklarına göre daha yüksek antioksidan aktiviteye sahip olduğu bulundu.

Anahtar kelimeler: Antioksidan, Ekstraksiyon, Fenolik, Fitokimyasal, Turunçgil Kabukları

Determination of Bioactive Compounds and Antioxidant Activities of Citrus Peels

Abstract

Bioactive compounds present in fruits and vegetables are receiving increased because they may help the protect humans against some diseases. These chemicals can reduce the free radicals damage caused to the cells, as a result of oxidative stress and they have been linked to reductions in the risk of major chronic diseases such as cancer, cardiovascular disease, obesity and other disease. In the present study, the bioactive compounds and antioxidant properties of citrus peels were examined. Fruit peels were obtained from lemon (Citrus limon), orange (Citrus sinensis, mandarin (Citrus reticulata) and grapefruit (Citrus paradisi). Total carotenoid, beta carotene, ascorbic acid, anthocyanin, total phenolic and flavonoid content were determined using colorimetric methods. The total antioxidant activities were analysed according to TEAC, FRAP and DPPH methods. It was found that mandarin and lemon peels were rich in carotenoid compounds and ascorbic acid, respectively while grapefruit and lemon peels were rich in phenolic compounds and had higher antioxidant activities than mandarin and orange peels.

Keywords: Antioxidant, Citrus Peels, Extraction, Phenolic, Phytochemical

Kaynak: https://dergipark.org.tr/download/article-file/328757

Acid / Base Extraction and Separation of Acidic and Neutral Substances

Experiment 3: Acid/base Extraction and Separation of Acidic and Neutral Substances

Introduction

You will be given a mixture that contains three substances in equal amounts: benzoic acid, 2-naphthol and 1,4-dimethoxybenzene (p-dimethoxybenzene):

Your task: to separate these three compounds by taking advantage of differences in their acidity.

Definitions:

There are two terms we use when separating compounds from organic products:

1. To remove organic compounds (what you want) from aqueous solutions (or what you don’t want), we perform an “extraction”. For neutral organic compounds, we often add an organic solvent to dissolve a neutral organic compound to separate it away from inorganic, aqueous soluble “trash”. In today’s lab, we are adding a base to form an ionic salt from the organic compound, which will make it water soluble to separate it from the compound(s) still soluble in the ether solvent.

2. To remove inorganic unwanted compounds from what we want, we perform a “wash”. We add aqueous solutions to our organic compounds so they “wash” away  impurities.

• To remove acids, we add bases.

• To remove bases, we add acids.

• To remove salts, we just sometimes wash with water.

Today you will be extracting your compounds from a mixture. In their neutral, covalent forms, all three compounds are soluble in a slightly polar organic solvent such as diethyl ether (CH3CH2OCH2CH3) but are fairly insoluble in water. This is because they are composed of many non-polar C-C and C-H bonds and have only a couple polar covalent bonds. Generally they are relatively non-polar, and only relatively non-polar organic solvents want to surround them. However, benzoic acid and 2 naphthol are acidic due to their –OH groups and so will be converted to their ionic salt forms on reaction with an appropriate base.

Source: https://tigerweb.towson.edu/jdiscord/www/331_lablectures/acidbaseextractionlablecture.pdf

Extraction And Determination Of Crude Fat From Plant And Animal Tissues ( Ms. Nadia Amara )

Extraction And Determination Of Crude Fat From Plant And Animal Tissues

Ms. Nadia Amara

Introduction of Crude Fat :

Determination of Crude Fat is the term used to refer to the crude mixture
of fat material present in a sample.

Crude fat is the traditional measure of fat in food products.

Fat is important to all aspects of meat production and processing.

Lipids/fats are relatively non-polar molecules, they can be pulled out of a
sample using relatively non-polar solvents. (With a non-polar solvent, only
non-polar molecules in the sample dissolve while polar ones do not ).

The lipid materials may include triglycerides, diglycerides, monoglycerides, phospholipids, steroids, free fatty acids, fat soluble vitamins, carotene pigments, chlorophylls, etc.

Crude fat content is determined by extracting the fat from the sample using
a solvent, then determining the weight of the fat recovered.

The common approach for total crude fat determination is based on the
solubility of lipids in non-polar organic solvents such as hexanes, petroleum
ether, or other non-polar solvent .

In this lab we will determine the crude fat extracted by petroleum ether
solvent .

This method is applicable to extractions of oilseeds, meats, feeds, and foods.

Calculation :

Crude Fat % ( % of Dry matter) = (weight of crude fat + weight of extraction
flask )-(weight of extraction flask) / weight of sample *100

Principle of Soxhlet extraction :

Soxhlet extraction is a continuous solid / liquid extraction.

A solid which contains the material to be extracted is placed in what is called a thimble.

A thimble is made out of a material which will contain the solid but allow liquids to pass through. A lot like filter paper.

The thimble containing the material is placed in the Soxhlet extractor.

An organic solvent is then heated . As it boils its vapors rise up and are
condensed by a condenser. The condensed solvent then fills up the thimble,
and after it fills with enough solvent it automatically siphons back down
into the container of organic solvent.

This process takes place over and over again until all the material to be
extracted from the solid in the thimble is now extracted into the organic
solvent.

This cycle may be allowed to repeat many times, over hours or days.

The advantage of this system is that instead of many portions of warm solvent being passed through the sample, just one batch of solvent is recycled.

After extraction the solvent is removed, typically by means of a rotary evaporator, yielding the extracted compound. The non-soluble portion of the extracted solid remains in the thimble, and is usually discard.

1: Stirrer bar/anti-bumping granules

2: Still pot (extraction pot) – still pot should not be overfilled and the volume of solvent in the still pot should be 3 to 4 times the volume of the soxhlet chamber.

3: Distillation path

4: Soxhlet Thimble

5: Extraction solid (residue solid)

6: Syphon arm inlet

7: Syphon arm outlet

8: Reduction adapter

9: Condenser

10: Cooling water in

11: Cooling water out


Extraction & Determination of Crude Fat From Plant or Animal Tissues ( ABDALQADER A. ABBAS )

INTRODUCTION

The term “lipid” refers to a group of compounds that are soluble in water, but show variable solubility in a number of organic solvents. The lipid content of food determined by extraction with one solvent may be quite different from the lipid content as determined with another solvent of different polarity.

Fat content is determined by often by solvent extraction methods, but it is also can be determined by non-solvent wet extraction methods and by instrumental methods that rely on the physical and chemical properties of lipids.

The method of choice depends on a variety offactors, including the nature of the sample, the purpose of the analysis and instrumentation available.

A Soxhlet extractor is a piece of laboratory apparatus invented in 1879 by Franz von Soxhlet. It was originally designed for the extraction of a lipid from a solid material.

This experiment so uses a soxhlet method to determine the lipid contents of plant & animal tissues.

The Soxhlet method for determining crude fat content is a lengthy process requiring up to a day for a single analysis. The solvent extraction step alone
takes six hours.

The method is therefore not favoured for routine testing purposes in the meat industry, rather it is used as a standard reference method.

In principle, fat is extracted, semi continuously, with an organic solvent.

Solvent is heated and volatized then is condensed above the sample.

Solvent drips onto the sample and soaks it to extract the fat. At 15-20 min interval, the solvent is siphoned to the heating flask, to start the process again.

Fat content is measured by weight loss of sample or weight of fat removed.

OBJECTIVE

1. To extract fat from various plant & animal tissues by an exhaustive extraction using a Soxhlet extractor

2. To determine percent of fat content in a food sample by weight in a sample.

3. To study the function of extraction process by Soxhlet extractor

1: Stirrer bar/anti-bumping granules

2: Still pot (extraction pot) – still pot should not be overfilled and the volume of solvent in the still pot should be 3 to 4 times the volume of the soxhlet chamber.

3: Distillation path

4: Soxhlet Thimble

5: Extraction solid (residue solid)

6: Syphon arm inlet

7: Syphon arm outlet

8: Expansion adapter

9: Condenser

10: Cooling water in

11: Cooling water out

Schematic diagram of a Soxhlet extractor.

THE SOXHLET EXTRACTOR

Continuous extraction of a component from a solid mixture.

Boiling solvent vapors rise up through the larger side-arm

Condensed drops of solvent fall into the porous cup, dissolving out the desired component from a solid mixture

When the smaller side-arm fills to overflowing, it initiates a siphoning action.

The solvent, containing the dissolved component, is siphoned into the boiler below

Residual solvent then drains out of the porous cup, as fresh solvent drops continue to fall into the porous cup.

. . . and the cycle repeats . . .

It should look something like THIS: (only much SLOWER)

This program will re-start in one minute. To terminate, press Esc


Laboratory‎ > ‎Liquid – Liquid Extraction

INTRODUCTION

When a solution of a solute in one solvent is shaken with a second solvent, which is immiscible with the first, the solute distributes itself between the two solvents in proportion to its solubility in the two pure solvents. Thus a constant ratio is set up between the concentrations of the solute in the two phases or immiscible solvent layers. This ratio or equilibrium can be represented by the equation:

             C1

K  =  ———

            C2     

K is called the distribution or partition coefficient. C1 and C2 are the concentrations of the solute in the two solvents. These concentrations are expressed in grams/mL.

K is approximately constant for all concentrations of C1 and C2. However, K will vary with temperature as solubility is temperature dependent.

Properties of a Good Extracting Solvent

Properties desirable for a good extracting solvent are:

  • It should be immiscible, or very sparingly soluble in the liquid from which the solute is to be extracted.

  • It should readily dissolve the substance to be extracted.

  • It should be capable of being easily separated from the solute after the extraction. This is usually by distillation.

  • It should ideally be cheap and non-flammable.

Choice of Solvents

The choice of immiscible solvent pair can be generalized as follows. One solvent should be polar and the other solvent should be considerably less polar. The polar solvent is usually water and the low polarity solvent is diethyl ether or a volatile hydrocarbon.

A useful generalization in predicting solubility and hence partitioning between solvents is the following:

Salts and other compounds having an ionic structure are generally soluble in water and insoluble in ether and hydrocarbons. Conversely, organic compounds, including the unionized forms of organic acids and bases are generally insoluble in water and soluble in ether and organic solvents. However it must be remembered that most compounds have some solubility in both types of solvents.

Solid-Liquid Extraction

When the analyte needs to be extracted from a solid material rather than a liquid, it is refrred to as a solid-liquid extraction. In this case, a solid sample is placed in the same container as the liquid and the analyte is separated from the solid because it dissolves in the liquid while the other sample components do not.

The extraction process can be carried out in two ways:

  • The sample and the liquid are shaken together in the same container. The resultant mixture is filtered, and the filtrate, which then contains the analyte, is collected.

  • The fresh extracting solvent is continously cycled over a period of hours through the solid sample via a continuous evaporation-condensation process. This maximizes the transfer of the analyte to the liquid phase and the filtrate is collected. This technique is known as a Soxhlet extraction. The advantages of this technique are:

    • fresh solvent is continuously in contact with the sample without having to introduce more solvent, which could dilute the extract.

    1. the process is automated so that the extraction can be conveniently set to occur overnight if desired.

MATERIALS

Separatory funnel, acidic,basic and neutral organic compound,ether,erlenmeyer flask,beaker and pipet.

PROCEDURE

1 g of  each  acidic, basic and neutral organic compound  were weighed.These compounds were dissolved in 30 mL of ether.Solution was poured into the separatory funnel.25 mL  % 5  HCl was added and the organic base was extracted from mixture by using seperatory funnel using method of shake and vent.Then the lower aqueous layer was poured into one erlenmeyer flask.The organic acid was extracted from the mixture using 25 mL of NaOH and 10 mL of water.Again all the lower aqueous layer was poured into one erlenmeyer flask.Finally in the remaining ether layer neutral compound existed.

DISCUSSION

Liquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their solutionpreferences for two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid phase. Liquid-liquid extraction is a basic technique in chemical laboratories, where it is done in separating funnels, as well as a common process in chemical industry and ore processing.

In the practical use, usually one phase is a water or water-based (aqueous) solution and the other an organic solvent which is immisciblewith water. Solvent extraction is used in nuclear reprocessing, ore processing, the production of fine organic compounds, the processing of perfumesand other industries. It is interesting to note that liquid-liquid extraction is possible in non aqueous systems, for instance in a system consisting of amolten metal in contact with molten salt, metals can be extracted from one phase to the other. This is related to a mercury electrode where a metal can be reduced, the metal will often then dissolve in the mercury to form an amalgam which modifies the electrochemistry greatly. For example it is possible for sodium cations to be reduced at a mercury cathode to form sodium amalgam, while at an inert electrode (such as platinium the sodium cations will not be reduced, instead water is reduced to hydrogen).

It is important to note that if a detergent or fine solid can stablise an emulsion which in the solvent extraction community is known as a third phase.

EXPERIMENT 3

PRELAB QUESTIONS

1- Extraction is a method for moving a compound from one medium to another. For example, if you make coffee from coffee beans, you are extracting some flavorful components of the bean and some caffeine into the water. The remainder of the beans (grounds) are left behind and discarded. This is called a solid-liquid extraction. If you are trying to move a compound from one liquid phase (solvent 1) into another liquid phase (solvent 2), this is liquid-liquid extraction but the two solvents must be immiscible or insoluble to the extent that they form two distinct layers.

By measuring the concentrations of compound in the two solvents (c1 and c2) we obtain a distribution coefficient, K, which is a constant for a given compound and given solvents at a given temperature, irrespective of the amounts of solvent present. A simple equation shows the relationship K=c2/c1.

Separatory Funnel: This glass equipment is very cleverly designed to carry out the task of separating two immiscible liquids (which form two distinct layers). Work with this equipment in a proper fashion and it will perform remarkably well

2-It is not always possible to quantitative remove the solute using a single extraction.Your options typically are to increase the volume of the extracting solvent(not usually good idea) and use multiple extractions.Multiple extractions can effectively remove a single species or a group of related species at the same time.So only uses small amount of solvent is the advantage.

3-  When an organic solvent has been exposed to aqueous solutions it will contain a small amount of water, the amount depending on the solubility of water in the solvent. To prepare a pure product, it is necessary to dry the solution using an appropriate drying agent. A drying agent is usually an anhydrous inorganic salt which reacts with the water present to form a hydrate. Anhydrous MgSO4, for example, reacts with water to form the heptahydrate MgSO4 7H2O.  Drying agents are distinguished by their capacity (the amount of water they can absorb), the rate at which they absorb the water, and their intensity (or completeness), which is the amount of water left behind in the solvent at equilibrium.

We can use drying agent in the extraction process.The product can be isolated from the organic solvent with drying agent. The most commonly drying agents are magnesium sulfate,sodium sulfate and calcium chloride.

Solid Liquid Extraction ( Ali OK )

Firstly, some amount of dried hazelnut sample was taken and put into the mixer to grind and to reduce the particle size. Then cloth bag which we put our sample and funnel were weighted. Our sample was weighted as 259,1g.Top of the cloth bag was tied up strongly and put into extractor vessel. After that the solvent pump was adjusted to 10 ml/min and temperature of solvent to 40-42 ◦C. The extractor was worked for 20 min. At the end of the period cloth bag was taken and weighted. Our grinded hazelnut sample with solvent was dried in an oven for 10 min to evaporate the solvent(dicholorometan). Dried sample was weighted and amount of oil extracted oil was calculated and our sample was put into cloth bag again. It was tied up and put into extractor vessel and the same procedure was applied three times at the time of period of 20 min.

Extracted oil and solvent were separated from each others in a distillation column under vacuum heating. Results were recorded and the graph was plotted as time(min) vs. oil (gram).

Solid-Liquid Extraction for Pharmaceutics, Food Processing and Pulp Industry ( W.M. Zadorsky )

1. Introduction

Vegetable oils, sugar, instant coffee, medicines from medicinal plants, etc. are made by processing solid starting material using extraction with liquid solvent(s).

Its initial step is passing the extractant through bulk of the solid in a possibly intimate contact. The contact, however, may be inhibited by air present in interstices between and pores within the pieces to be contacted with the extractant. The air will block penetration of the extractant into some of such cavities. This results in slow and incomplete extraction.

It is therefore desirable to provide a method to remove air blocks in the material to be processed and/or increase the diffusion rates.

High pressure equipment is conventionally used to do this. However, it is expensive, energy-consuming and not always efficient.

The project is aimed at developing a rapid, effective, environmentally friendly and low-cost method to ensure complete extraction of valuable components from solid materials.

2. Project Description

2.1. Process Development

The method requires only minor additions to the existing equipment and may make expensive high-pressure equipment unnecessary. It relies on a simple three-step treatment of the starting material directly before contacting. The pretreatment removes all air trapped in the open pores and involves the following short-time steps carried out in quick succession:

heating the charge, introducing a specific non-reactive gas, and desorption of the gas.

It activates every interstice and open pore and results in their quick and complete filling during the contacting step.

An advantage of the pretreatment is that it can be conveniently combined with other means of activation like self-excited oscillations, pulsed pressure and acoustic fields.

2.2. Materials and Equipment

The non-reactive gas characteristics and the timing are unique to each solid/extractant system. This necessitates their tailoring to the system at hand. The gas will invariably be selected among those inexpensive and readily available ones.

2.3. Process and Product Characteristics

Laboratory experiments and commercial use with medicinal plants demonstrated that the method is both effective and readily adaptable to various production routes. The contacting step as such was effected very rapidly and resulted in complete contact between the solid and the solvent. This increased production rate, enhanced product quality and reduced wastes