PHARMACOGNOSY I (6)

Page 1: Introduction to Flavonoid Glycosides

Slide Title

  • PHARMACOGNOSY I PHAR301

  • Lecturer: Dr. Beste Atli

  • Topic: Flavonoid Glycosides

Page 2: General Characteristics of Flavonoids

Solubility

  • Flavonoid glycosides are soluble in water and water-alcohol mixtures.

  • Insoluble in organic solvents.

  • Aglycones are soluble in non-polar solvents.

Crystallization

  • Mostly crystallized compounds that yield a yellow solution in alkaline medium.

  • Addition of acid causes the yellow color to disappear.

Page 3: Extraction Methods for Flavonoids

Techniques Used

  • Different extraction methods employed when both flavonoids and glycosides are present.

  • Elution with:

    • Acetone, ethanol, or methanol-aqueous solutions.

    • Liquid-liquid extraction techniques (e.g., petroleum ether for chlorophyll, diethyl ether, or CHCl3 for aglycones).

Page 4: Concentration Technique

Steps Involved

  • Begin with concentrated extract (acetone-, ethanol-, or methanol-aqueous solutions) to isolate residual components (e.g., pigments).

  • Use CHCl3 or DEE for separation of free flavonoids.

  • Employ EtOAc to isolate glycosides.

Page 5: Types of Flavonoids and Their Solvents

Classification of Flavonoids

  • Discusses various types such as:

    • Isoflavones

    • Flavanones

    • Dihydroflavonol

    • Methylated flavone/flavonol derivatives

  • Common solvents: acetone, alcohol, water.

Page 6: Chromatographic Techniques

Separation Processes

  • Various chromatographic methods employed for the separation and purification process including:

    • Polyamide

    • Sephadex

    • Silica gel

    • Alumina (Al2O3)

    • HPLC.

Page 7: Determination Reactions for Glycosides

Chromatographic Identification

  • Chromatographic methods give fluorescence under UV light.

  • In alkaline medium, a yellow color indicates the presence of certain compounds.

  • Aurones and chalcones can be visually detected with ammonia vapors (producing orange/red colors).

Page 8: Color Tests for Flavonoids

Reagent Specific Tests

  • 1% AlCl3/EtOH gives a yellow fluorescence for flavones.

  • 1% PbOAc indicates flavonols with an orange color.

  • 1% FeCl3 detects dihydro derivatives (green) and polyhydroxy derivatives (blue).

Page 9: Classical Color Reactions for Antioxidants

Specific Reactions

  • Cyanidin reaction (Shinoda reaction).

  • Color reactions with HCl and Mg/Zn powder facilitate color identification:

    • Flavones yield orange, flavonols yield red, flavanones yield purple, chalcones yield colorless.

Page 10: Further Color Reactions

Specific Tests

  • In alkaline conditions, flavones with H2SO4 yield yellow while chalcones with SbCl5/CCl4 yield red-violet.

  • Boric acid in dilute H2SO4 and FeCl3 tests provide color indications of hydroxyl groups.

Page 11: Identification Tests for Anthocyanins

Test Procedures

  • Use of diluted HCl generates red, NaOH produces blue, and lead acetate gives green colors for identification.

  • Reaction with amyl alcohol accompanied by heating leads to specific coloration (wine-red, pink-red).

Page 12: Quantitative Determination

Techniques

  • Use of colorimeters for % transmission readings, calibrated at 740 nm with specific sample preparations homing on red wavelengths.

  • Employing HPLC for sample filtration.

Page 13: Biological Activities of Glycosides

Highlighted Activity: Vitamin P

  • Structures with hydroxyl groups at positions 3', 4' reduce capillary permeability.

  • Associated with treatments for circulatory disorders (e.g., arteriosclerosis, varicose veins).

  • Sources include orange, lemon, rose hip, and red pepper.

Page 14: Diuretic and Diaphoretic Effects

Notable Compounds

  • Luteolin, apigenin, rutin, kaempferol, quercetin noted for diuretic properties.

  • Commonly used plants include Chamomillae flos and Tiliae flos.

Page 15: Antispasmodic Activities

Key Plants

  • Chamomillae flos, Tiliae folium, Rutae herba, Crataegi flos, and Viburni cortex recognized for antispasmodic effects.

Page 16: Chemical Structures

Structure Examples

  • Explains the structural characteristics and hydroxyl groups in compounds such as Quercetol and Rutin which influence their functions.

Page 17: Anti-inflammatory Properties

Highlighted Compounds

  • Discusses Apigenin and Hypolaetin-8-glucuroside for their anti-inflammatory benefits.

Page 18: Antimicrobial Effects

Summary of Effects

  • Compounds like Rutin and Quercetol described for their antibacterial, antifungal, and antiviral properties.

  • Phytoalexins are categorized by their unique structures.

Page 19: Antihistaminic Effects

Notable Plant

  • Scutellaria baicalensis identified for its antihistamine effects.

Page 20: Estrogenic and Antiestrogenic Properties

Isoflavonoids

  • Examples include Glycine max (soybean), Lepidium capitatum, and Trifolium repens.

Page 21: Insecticidal Effects

Example Compounds

  • Rotenoids detailed for their insecticide effects, particularly those with tetrahydrofurane structure from Derris eliptica.

Page 22: Cardiovascular Actions

Heart Health

  • Crataegus monogyna mentioned for effects on heart contractions & as a coronary vasodilator with antiarrhythmic properties.

Page 23: Purgative Properties

Caution

  • Noted that misuse is unauthorized (referring likely to Prunus japonica).

Page 24: Hepatoprotective Properties

Specific Compounds

  • Flavonolignans (Silybum marianum) detailed for their liver-protective functions.

Page 25: Anthocyanins as Dyes

Industrial Uses

  • Highlights practical uses of anthocyanins from plants (e.g., red cabbage, grape) in coloration within industries.

Page 26: Therapeutic Applications

Specific Treatments

  • Target conditions like capillary and venous disorders, my having symptoms like leg pain, weakness, and muscle cramps.

Page 27: Therapeutic Uses Continued

Specific Applications

  • Addressing menorrhagia, impaired retinal circulation, and symptoms associated with menopause through products like Diosmin and Rutin.

Page 28: Flavonoid-Bearing Plants

Example and Use

  • Ginkgo biloba (Ginkgoaceae) mentioned for its medicinal properties and preparations from the leaves.

Page 29: Ginkgo Compounds

Active Components

  • Bilobalide and ginkgolides, as well as flavonoid derivatives like Quercetin.

Page 30: Ginkgo Effects

Health Benefits

  • Mainly used for cognitive issues including amnesia, tinnitus, and dementia.

Page 31: Tebokan® and Its Uses

Product Overview

  • Tebokan® designed for symptoms relating to brain and limb perfusion disorders, aiding in memory and anti-vertigo functionality.

Page 32: Passiflora incarnata

Characteristics

  • Details features of the purple passion flower including key constituents like Vitexin.

Page 33: Thymus vulgaris Overview

Overview

  • Common thyme noted for its medicinal uses; includes its derivatives and oil extracts.

Page 34: Chemical Structures of Thymus

Relevant Compounds

  • Attributes of apigenin and luteolin are discussed, along with their significance.

Page 35: Thyme Species

Variants of Thyme

  • Lists known species with noted uses, such as Coridothymus capitatus and Thymbra spicata.

Page 36: Thyme Species Continued

Additional Species

  • Continuation of thyme species identification.

Page 37: Citrus Family Overview

Highlighted Species

  • Discusses various Citrus species and their uses in therapy, including drug names and origins.

Page 38: Flavonoid Structures in Citrus

Compounds

  • Representation of specific flavonoids such as Rutin and Diosmin from citrus sources.

Page 39: Silybum marianum Overview

Key Characteristics

  • Description of the plant family, name, and preparation in pharmaceutical forms.

Page 40: Silymarin Composition

Active Components

  • Silymarin acts on the liver, constituting 1.5-3% of the drug composition from flavonolignans.

Page 41: Achillea millefolium Overview

Identification

  • Common yarrow, its family, and drug uses highlighted.

Page 42: Active Constituents of Achillea

Therapeutic Activities

  • Discusses essential oils and their various therapeutic benefits including choleretic and anti-inflammatory properties.

Page 43: Equisetum arvense Overview

Characteristics

  • Describes the field horsetail, its height and structure, and key family classification.

Page 44: Morphology of Equisetum

Visual Description

  • Detailed examination of the morphology with focus on reproductive structures and characteristics during seasons.

Page 45: Growth Features

Botanical Attributes

  • Addresses the clear distinction of fertile and sterile forms in horsetail plants.

Page 46: Chemical Structures

Key Compounds

  • Highlights the structures of Kaempferol and Quercetin derivatives and their relevance in pharmacognosy.