Extraction, Separation and Structure Elucidation of Natural Products PDF

Extraction, Separation and Structure Elucidation of Natural Products alanoud alharbi bushra albeladi Extraction is the process of separating a specific compound from a complex mixture, usually from plants, animals, or microorganisms. This is often the first step in th...

Extraction, Separation and Structure Elucidation of Natural Products alanoud alharbi bushra albeladi Extraction is the process of separating a specific compound from a complex mixture, usually from plants, animals, or microorganisms. This is often the first step in the isolation and purification of bioactive compounds. 01 02 03 04 Black, refined ) and of fine mesh or macroporous, charcoal is solvents or a combination of both (e.g., aqueous methanol ) 01 WATER-STEAM DISTILLATION 02 SUPERCRITICAL FLUID EXTRACTION 03 liquid–liquid extraction 04 activated charcoal REFINED ISOLATION TECHNIQUES AND CHROMATOGRAPHY  ion exchange chromatography Thin layer chromatography (TLC) silica gel column chromatography. Gas chromatography (GC) TLC is the simplest and fastest method, using precoated silica gel plates to separate mixtures based on different retention times as the solvent migrates up the plate. An example of a natural product separated by Thin Layer Chromatography (TLC) is the separation of plant pigments, such as chlorophyll, carotenoids, and xanthophylls, GC is used for separating volatile and nonpolar compounds, such as oils and fatty acids, by passing a carrier gas over a heated, coated column, with the sample often converted to methyl esters for better resolution. There are various chromatographic systems suited for separating polar compounds. Polar compounds, often soluble in aqueous systems, can be effectively separated using ion exchange chromatography, especially when the compounds have a charge due to the presence of either positive or negative functional groups. EXAMPLE : Different soy proteins such as glycinin and β- conglycinin are separated as they elute from the column at different points due to their varying charge properties. HPLC HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY HPLC operates by passing a liquid sample through a column packed with small particles (stationary phase). The different components of the sample interact with the stationary phase and the mobile phase (a liquid solvent), resulting in their separation based on various chemical properties like polarity, molecular size, and charge Types of HPLC: 1.Reverse-Phase HPLC (RP-HPLC) 2.Normal-Phase HPLC 3.Size-Exclusion Chromatography (SEC) 4.Ion Exchange Chromatography (IEC) Normal-Phase HPLC:  Modern HPLC systems use macroporous resins with very small bead sizes, typically ranging from 2.5 to 3.0 microns. Smaller beads generally provide higher resolution and faster separations.  The stationary phase is polar (e.g., silica ,copolymerized polystyrene and divinylbenzene), and the mobile phase is non- polar (e.g., hexane).  Polar compounds are retained longer, and non-polar compounds elute faster. Reverse-Phase HPLC (RP-HPLC):  Most common type.  The stationary phase is non-polar (e.g., C18 ,C2 TO C30), and the mobile phase is polar (water/organic solvent mixture).  Non-polar compounds are retained longer, while polar compounds elute faster.  Applications include separations of the long chain, structurally related isomers (e.g., carotenoids, steroids, etc.). GPC POLYAMIDE GEL CHROMATOGRAPHY  Porous polyamide resin: Has hydrogen bond acceptor properties.  Ideal for separation: Effective for polyphenolic solutes such as phenolic acids, flavanols, and flavonoids.  Solvent mixtures: Common solvents include aqueous acetic acid and ethanolic solutions. SEC SIZE-EXCLUSION CHROMATOGRAPHY  In size-exclusion chromatography (SEC), molecules in solution are separated accord_x0002_ing to their size (i.e., molecular weight).  This chromatography has been well adapted to the separation of large molecules, particularly proteins and industrial polymers.  Types of SEC:  Gel Filtration Chromatography: When an aqueous solution is used as the mobile phase.  Gel Permeation Chromatography: When an organic solvent is used as the mobile phase  Sephadex LH20  A popular gel known as Sephadex LH20 is widely used to separate small and medium size phenolic com_x0002_pounds such as flavonoids and phenolic acids.  Conversely, the LH-20 gel can be used as a filtration method whereby unwanted phenolic compounds can be retained on the gel, allowing the desired compounds of interest to pass through.  Structure Elucidation 01 02 03 04 05 06 THANK YOU FOR WATCHING