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All leaf

This document provides information on the leaf structure and morphology of plants. It defines a leaf and describes leaf characteristics such as shape, size, texture, venation, and margin. It discusses leaf types including simple, compound, and modified leaves. The internal structure of leaves is examined including the epidermis, mesophyll, vascular tissue, and trichomes. Stomata types and distribution are covered. Specific leaf details are given for Digitalis purpurea and Digitalis lanata, medicinal plants used for their cardiac glycoside content.

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The Leaf (Latin: Folium) • a lateral outgrowth or an appendage on the stem. • possesses neither nodes nor internodes and buds or lateral branches arise in its axil. • Characters: • - flattened form • - thin texture • - presence of chlorophyll • - presence of veins
Leaf Morphology Leaf lamina Stipule Petiole Node Internode Axillary bud Stem Axil
1- Cotyledons (Seed leaves). 2-Foliage leaves (green ordinary leaves) 3-Bracts 4-Modified Leaves Needles and Spines Two Seed Leaves and One Tiny True Leaf Types of leaves Tendrils
Phyllotaxis • It is the disposition of the leaves on the stem. • The leaves being arranged on the stem in a definite manner characteristic for each species of plants.
Types of Phyllotaxis Alternate Opposite Whorled decussate
SessilePetioled Leaf petiole (stalk)
Leaf base Sheathed Ligulate Stipulate Exstipulate Decurrent
Axil Lamina Leaf Apex Vein Mid-rib Petiole Stipule Simple Leaf Stem
Compound leaf
Forms of Compound leaves Paripinnate Imparipinnate Palmate Ternate Bipinnate
General description of the lamina of a simple leaf • general outline or shape • Size • Apex • Base • Margin • Venation • Surface • texture
General outline or shape • a- when the lamina has nearly the same width: Filiform (Fennel) Acicular (Pinus) Tubular (Onion) Linear (Grasses) Oblong (Cassia)
• b- when the lamina has the widest portion near the base: Continued: General outline or shape Lanceolate (Long Buchu) Ovate (Boldo) Ensiform (Eucaluptus) Cordate (Ipomea) Sagitate (Rumex) Hastate (Convolvulus) Reniform (Asarum)
Continued: General outline or shape • c- when the lamina has the widest portion near the apex: Obcordate (Oxalis) Obovate (Dog Senna) Spathulate (Uva Ursi ) Lyrate ( Brassica)
Continued: General outline or shape • d- when the lamina is symmetric or round: Orbicular (Nymphea) Elliptical (Pear) Oval (Boldo)
Size of the leaf • the length from the base to the apex and the broadest width • it varies from tiny leaves (few millimeters) as Savin to a very considerable size as banana • In leaves used in medicine the doesn’t exceed about 30 cm long as Digitalis • Leaves vary in size on the same plant being bigger at the base and becoming smaller as getting near the apex
Apex of the leaf Acute (Hyoscyamus) Acuminate ( Stramonium) Obtuse (Oval Buchu) Recurved (Short Buchu)
Margin of the leaf Entire (Senna) Revolute (Uva-Ursi) Dentate Serrate (Peppermint) Spiny
Continued: Margin of the leaf Bidentate Crenate (Digitalis) Lobed
Base of the lamina Symmetric Asymmetric Decurrent
Venation Parallel Reticulate
Surface of the lamina Smooth (Uva-Ursi) Punctate (Buchu) Glabrous (Coca) Pubescent Hairy
Texture of the lamina Membranous Papery Coriaceous Succulent
Structure of the leaf (Microscopical characters)
Epidermis: • mainly a protective layer • It occurs on the surface of plants and it is a complex tissue consisting of epidermal cells, trichomes (hairs) and stomata • Epidermal cells: • It consists of a single layer of cells, but in some cases it may become many layered as a result of division • many layered epidermis often acts as water storage tissue and the inner layer is often described as hypodermis • tubular or lenticular with complete absence of intercellular spaces except where the stomata occur
• appear in surface view polygonal: - approximately isodiameteric in Dicots - axially elongated in Monocots Leaf epidermis in Dicots (suface view) Leaf epidermis in Monocots (suface view)
• The anticlinal walls perpendicular to the surface: - straight as Senna, Coca - wavy as Belladonna - beaded due to unequal thickening or thickenings as Digitalis • The epidermis outer walls are: - convex - cellulosic - mostly thickened - covered with cuticle cuticle epidermis
• Cuticle varies in thickness - thin in shady plants as Digitalis - thick in sunny regions plants as Uva Ursi Thin epidermal cuticle Thick epidermal cuticle
• Cuticle may be: - smooth as Stramonium - finely ridged appearing in surface view striated as Belladonna - formed mainly of cutin which is an aggregate of modified fatty acids, partly combined with alcohols • Epidermal cells are devoid of content • in some cases may contain certain contents • as: -calcium oxalate as Savin • - calcium carbonate as Cannabis • - diosmin as Buchu • - mucilage as Senna
Trichomes or hairs • Epidermal cells are sometimes extended outwards forming projections of variable shapes and sizes • If they are short and conical papillae and the epidermis described papillosed these appear in surface view as circles in the middle of the cells
• If the trichomes are long trichomes or hairs - The part embeded in the epidermis foot - The free part body - Covered with cuticle which may be smooth as Hyoscyamous or warty as Senna - Either of covering type as non-glandular trichomes or of secretory function as glandular trichomes - Secretions may be volatile oils or oleo-resin
Trichomes or Hairs Non-glandular Hairs (covering type) Glandular Hairs (secretory function) Uni-cellular multi-cellular multi-cellularUni-cellular
Multi-cellular (formed of more than one cell) Uni-cellular (formed of more than one cell) Unbranched (Simple) Ex: Senna Branched Ex: Cruciferae Unbranched (Simple) Branched Non-glandular Hairs
Uni-seriate (formed of one row) Ex: Belladonna, Digitalis Bi-seriate (formed of two rows each contain one cell (twin hair) ex: Arnica flower, or more cells ex: Calendula flower Pluri-seriate (formed of many rows shaggy hair) ex: Cumin Non-glandular Hairs multicellular unbranched (simple) hairs
Non-glandular Hairs Multi-cellular branched hairs Simple branched (with uni-seriate body ending in 2 branches) ex: Tobacco Stellate ex: Boldo Peltate (scale hair) Very short stalk surrounded by plate like structure of closely joined cells ex: Olea Balance hair (T-shaped hair) ex: Pyrethrum
c Glandular hairs I- Unicelluar (pear gland): -not of common occurrence, present in Piper. - the foot is embedded in the epidermis and the swollen head is projecting outside
II- Multicellular glandular hairs - the most common type. - consist of several cells and are classified into: Uniseriate stalk Biseriate stalk and biseriate head (Compositae hair) Pluriseriate stalk and a head with 8 radiating cells ex: Cannabis Branched stalk (Branched hair) ex: Hyoscyamus muticus
Uni-seriate stalk multi-cellular glandular hairs Uni-cellular head Multi-cellular head One-celled stalk ex: Digitalis 2-3 celled stalk ex: Belladonna, Lavender
1- celled stalk & 2-celled head ex: Digitalis 1-or more celled stalk & many celled ovoid head ex: Hyoscyamous Uni-seriate stalk multi-cellular glandular hairs Uni-cellular head Multi-cellular head very short: 1- celled stalk & a head of 8 radiating cells ex: F: Labiatae Labiacious hair
• These are openings in the epidermis of stem and leaves. They occur in both surfaces or only on lower surface. • It’s a type of epidermal structure of a great diagnostic value • Consists of: - a central pore - two similar cells; the guard cells, kidney shaped in Dicots while they are dum-bell shaped in Monocots cStomata
• Stomatal number: • The average number of stomata per square mm. • It is of little value in distinguishing between closely allied species • Stomatal index: Stomatal index = S x 100 E + S • It is the percentage of number of stomata (S) in a certain area to the sum of total number of epidermal cells (E) and stomata together in same unit area. • Stomatal index is constant for a given species
Types of Stomata • 1-Moss type - The guard cells, during development, fuse with each other by lysis of the separating walls, thus the osteole becomes surrounded by a single cell Types of stomata according to characters of guard cells:
• 2- Gymnospermous: - The guard cells are oval or elliptical and inclined to the epidermis at an angle of approximately 45°. • 3- Graminaceous: - Stomata are usually rectangular in outline and the guard cells are dumbell-shaped, thin walled ends and narrow flat middle parts with outer and inner walls thickened. - It is frequently with 2 subsudary cells lying parallel to the long axis of the osteole
• 4- Dicotyledonous: - Stomata are elliptical or circular in shape as seen in surface view and surrounded by epidermal cells which vary in characters and arrangement. Types of stomata according to the characters and arrangement of surrounding cells (subsidary cells): 1- Ranunculaceous (Anomocytic) stomata: -Equal celled type - The stoma is surrounded by three to five subsidary cells are of varying number and almost of equal size -ex: Digitalis leaves
• 2- Rubiaceous (Paracytic) stomata: - Paracytic stomata - Parallel celled type - The stoma is surrounded by two or three subsidary cells , two of which having their long axis parallel to the axis of the osteole - ex: Senna leaf, Coca leaf
• 3- Caryophyllaceous stomata: - Diacytic stomata - Cross-celled type - The stoma is surrounded by two or three subsidary cells showing their long axis perpendicular to the axis of the osteole - ex: Mentha leaf
• 4- Cruciferous stomata: - Anisocytic stomata - Unequal celled type - The stoma is surrounded by usually three or more subsidary cells one of which is distinctly smaller than the others - ex: Solanaceous leaves
Mesophyll
• Palisade layer: • formed of one or more layers of cylindrical cells perpendicular to the epidermis with narrow intercellular spaces which is usually corrupted with the cortical tissues in the mid- rib region. • The upper palisade may form a continuous layer as Senna or dis-continuous as Hyoscyamus.
• Spongy tissue: • formed of chlorenchyma with large irregular cells with intercellular spaces. • Hypodemis: • The mesophyl is sometimes separated from the epidrmis by one or more layers of cells devoid of chlorenchyma called hypodermis • This is a protective tissue or water, it may be parechymatous, collenchymatous or sclerenchymatous
• Cortical tissue: • It is present in the mid-rib region • Can be formed of parenchyma as in Belladonna, or collenchyma as Uva Ursi. • Endodermis: • It is the inner-most layer of cortical tissue which is usually indistinguishable in medicinal plants.
• Pericycle: • present between the phloem and cortical tissue • mostly parenchyma but sometimes formed of collenchyma as Digitalis • Vascular system:
Bulliform cells Bundle sheath cells with chloroplasts Parenchyma with chloroplasts Phloem Xylem Lower epidermis Upper epidermis Sclerified fibers Collenchyma
Leaves containing cardiac glycosides
I-Digitalis leaf (Foxglove leaf) Digitalis lanata Allied Drug Digitalis purpurea Official Drug • Origin: Dried leaves of Digitalis purpurea and Digitalis lanata Family: Scrophulariaceae collected and dried rapidly at 550 C.
Indigenous to Europe and USA Collection is preferably before flower expansion and should be done in the afternoon
Digitalis pururea L. [Foxglove] Dried by: Drying chambers at 55°C, Vacuum drying oven, Lyophilization Digitalis lanata Ebrh. (Grecian foxglove) Official drug Allied drug
Digitalis lanataDigitalis purpurea Dried leaves of Digitalis lanata family Scrophulariaceae Collected and rapidlly dried in temperature not exceeding 55-60 C Dried leaves of Digitalis purpurea family Scrophulariaceae Collected and rapidlly dried in temperature not exceeding 55-60 C Grecian foxgloveFox glove Oblong lanceolate to linear lanceolateShape: Ovate to oblong ovate Entire or broadly serrateMargin: Crenate acute to acuminateApex: obtuse Papery, glabrousTexture: papery, wrinkled
Digitalis lanataDigitalis purpurea pinnate reticulate, lateral veins leave the midrib at very acute angle and appear nearly parallel. Venation: pinnate reticulate and anastomosing near the margin . The midrib is prominent on lower surface, depressed on upper, giving lamina checquered appearance. sessilePetiole: winged Symmetric, decurrentBase: symmetric decurrent Showed cilia at the lower third partSurface: pubescent Tea-like odorOdor, taste: Tea-like odor, bitter taste 1-Cardiac glycosides: Lanatosides A, B, C, D and E (tetra glycosides each containing an acetyl group) N.B.They are twice to four times as active as official drugs. Active constituents: 1-Cardiac glycosides : Purpurea A, Purpurea B 2-Saponins. 3-Flavonoids (luteolin). 4-Anthraquinone. Saponin, digitonin, tigonin, gitonin
Digitalis purpurea Digitalis lanata Oblong lanceolate to linear lanceolate acute to acuminate pinnate reticulate appear nearly parallel. Entire or broadly serrate sessile symmetric ovate to ovate lanceolate obtuse pinnate reticulate and anastomosing near the margin , checquered appearance Crenate Winged petiole symmetric decurrent
Upper epidermis Palisade Endodermis Xylem Phloem Pericycle (Collenchyma) Sub-epidermal collenchyma Sub acute apex crenate or dentate margin, Symmetric decurrent base Anastmosing veins T. S. diagram of Digitalis purpurea leaf Digitalis purpurea leaf
Non glandular hair (Clothing hair) (Uniseriate, multicellular) Glandular hair (bicellular head and unicellular stalk) Collapsed cell Glandular hair (unicellularhead and multicellular stalk Epidermal cells showing anomocytic stomata and cicatrix Digitalis purpurea powder Glandular hair (unicellular head and unicellular stalk)
Polygonal,isodiametric or slightly elongated with beaded anticlinal walls,thin and smooth cuticle with anomocytic stomata. Digitalis lanata powder
Digitalis lanataDigitalis purpurea The epidermal cells show beaded anticlinal walls, 10-14 celled non glandular hairs. Numerous irregular fragments of epidermis with stomata of anomocytic (ranunculaceous) type. Glandular hairs are: • Bicellular head and unicellular stalk • Unicellular head and 3-10 celled uniseriate stalk Numerous fragments of non-glandular hairs Very few glandular hairs. Calcium oxalate is absentSclerenchyma and crystals of Ca-ox are absent Fragments from petiole and large veins showing spiral, annular, and reticulate vessels
Digitoxose- Digitoxose-Digitoxose- Glucose Purpurea A Digitoxose- Digitoxose- Acetyl Digitoxose- Glucose Lanatoside A (glycone, sugar part) A = OH at 3,14 B = OH at 3, 14,16 C = OH at 3, 12,14 Aglycone, non sugar part Deoxy sugar Active Constituents
Purpurea glycosides A digitoxin Partial acid or enzyme hydrolysis glucose (1ry glycoside) (2ry glycoside) Digitoxin (2ry glycoside) acid hydrolysis 3 digitoxose (2-deoxy sugar)(aglycone) Purpurea glycosides B gitoxin Partial acid or enzyme hydrolysis glucose (1ry glycoside) (2ry glycoside) Gitoxin (2ry glycoside) acid hydrolysis 3 digitoxose (2-deoxy sugar)(aglycone) Digitoxigenin Gitoxigenin
Digitoxin + HOAC + glucose (Acetyl derivative of purpurea A) Lanatosides A Partial acid or enzyme hydrolysis Gitoxin + HOAC + glucose (Acetyl derivative of purpurea B) Lanatosides B Partial acid or enzyme hydrolysis Digoxin + HOAC + glucose Lanatosides C Partial acid or enzyme hydrolysis
Lanatoside A deacetylation Purpurea A Lanatosie B Purpurea B N.B: deacetylation is by controlled alkaline hydrolysis deacetylation N.B. Lanatosides are twice to four times as active as official drug.
 It is a cardio tonic.  It increases the contractility and improves the tone of the cardiac muscle  Slower and much stronger heart beat produced. It is used in most forms of cardiac failure.  It acts indirectly as diuretic  Uses:  Digitoxin is cumulative and its action must be watched. DOSE: 0.1 g of digitoxin
• Chemical tests of cardiac glycosides: 1- Baljet’s test 2- Kedde’s test for lactone ring 3- Liberman’s- Burchard test for steroidal ring 4- Keller- Killiani test for Deoxy- sugar
Boil powder with 70% alc. filter and shake with Pb acetate, filter, add Na2HPO4, filter Filtrate (F) 1) Baljet test (F) + (95 ml of 2% alcoholic picric acid + 5 ml of 10% alcoholic NaOH) orange color. Chemical test for cardiac glycosides in digitalis leaves ( for 5 membered lactone ring):
2-Keller-Killiani test: For deoxy sugar 1- Filtrate + CHCl3 CHCl3 extract Residue 2) Residue + glacial acetic acid (FeCl3) + H2SO4 on the wall of test tube bluish green color in the upper layer reddish brown ring (steroidal nucleus) evaporate
Name Origin Constituents Uses 2-Squill Squill is the sliced and dried scale leaves from the bulb of Urginea maritima L. Fam. Liliaceae 1- Cardiac glycosides; Scillaren A and Scillaren B. 2- 4-11% mucilage 3- Saponins. •Cardiotonic (like digitalis). •Expectorant in small dose and emetic in large dose.
Name Origin Constituents Uses Red squill It is a variety of Urginea maritima and owes its colour to presence of red anthocyanin dissolved in the cell sap. 1- Scillaren A and B glycosides 2- Toxic glycoside Scilliroside Poison for rats
Leaves containing anthraquinone Glycosides
Dried leaflets of Cassia acutifolia Delile, known as Alexandrian or Khartoum Senna, and of C. angustifolia Vahl, known as Indian Senna orTinnevelly Senna F. Leguminosae  Paripinnate leaflets  Compound leaves are alternate  Leaflets are opposite Senna Leaves
Cassia angustifolia Cassia acutifolia
Cultivated in Sudan (Cordovan) exported from Alexandria Indigenous to and cultivated in middle and upper Nile districts of Africa Cultivated in south India (Tinnevelly) Indigenous to Somalia and Arabia Khartoum senna Tinnevelly Senna Oblique lines
Microscopiocal differences between Alexandrian and Indian senna Indian sennaAlexandrian senna Item Less numerous. The average distance between each is about six epidermal cells More numerous. The average distance between each is about three epidermal cells. Hairs The stomata having two or three subsidiary cells respectively are in the ratio of about 7:3 Most of the stomata have two subsidiary cells only Stomata 19.5-22.525-29.5Vein- islet number 14-(17.5)-2010-(12.5)-15.5Stomatal index
Morphology • Composition : compound • Leaf lamina: (leaflet) • Shape : lanceolate to ovate lanceolate • Apex : acute mucronate with horny apiculus • Margin: Entire leaflets
Description of the diagram: 1- Isobilateral. 2- Palisade is continuous in midrib region. 3- Straight on upper surface & slightly prominent on lower surface. 4- Lower subepidermal collenchyma only. 5-V.B.: Endodermis: is indistinct. Type: collateral. Pericycle:lignified fibres. 6- Content : prismatic crystal forming crystal sheath & cluster crystal of calcium oxalate.
Crystal sheath T.S. sector
Powder Physical Characters: • Color: Light green to greenish-yellow • Odor: faint characteristic odor • Taste: mucilagenous slightly bitter taste
• 1-Epidermal cells with, paracytic stomata • 2- Warty hairs (Non-glandular, unicellular, curved or their cicatrix with radiating epidermal cells. • 3-Hyaline angular particles of mucilage which stain pink with ruthenium red.
• 3-Cluster crystals of calcium oxalate 4-Fragments of lignified spiral and annular xylem vessels. 5-Bundles of lignified pericyclic fibres accompanied by crystal sheath.
Active constituents 1- 2.5% anthraquinone : -Glycosides ,eg: sennoside A, B, C and D (dianthrone). -Aglycones, free anthraquinones , eg, rhein, aloe-emodin (Anthranol). 2- Flavonoid (kaempferol), 3- Mucilage and resin. Dianthrone
Chemical Test • 1- Powder +KOH----- rose red color • 2-Borntrager’s test: Powder+ organic solvent+ dil NH4OH • 3-Modified Borntraeger´s test: Powder + dil.H2SO4 Filtrate + benzene + dil NH4OH Boil, filter then cool rose-red colour (NH4OH layer) rose-red colour (NH4OH layer)
Action and Uses: Senna inhibits water absorption from the colon, stimulates muscular coat of the intestine to produce peristalsis. It gives soft stools and is used as: -Laxative (in small dose ) or purgative (in large dose) to treat acute constipation - Produce soft stools for patient suffering from Hemorrhoids & Anal fissure. -In x-rays examination or before abdominal surgeries( for evacuation) . Dose: 2g (infusion or decoction)
Contraindications Senna is contraindicated in patients with intestinal obstruction, ulcerative colitis, appendicitis. Senna is not recommended for children younger than 2 years of age. Pregnancy/nursing Use with caution Senna may cause diarrhea, loss of fluids, high blood potassium, and abdominal pain or cramping. Long-term administration of senna may cause liver damage.
Leaves used for urinary tract infection
4/25/2017 92 Uva- Ursi ( Bearberry )Buchu leavesItem Arctostaphylos uva- ursi, F. Ericaceae Barosma betulina (Thumb) F. Rutaceae. Origin (dried leaves of a- Phenolic glycosides (arbutin, and methyl arbutin) b. Tannin (gallic acid and ellagic acid). c- Flavonoid (quercetin) 1. Volatile oil (diosphenol –urinary antiseptic) 2. Diosmine ( Flavone - -glycoside) Active Const.
4/25/2017 93 Uva- Ursi ( Bearberry ) (‫ال‬ ‫عنب‬ ‫ورق‬‫د‬‫ب‬) Buchu leaves )‫البوكو‬ ‫ورق‬) Item 1- Urinary tract antiseptic 2. Diuretic. 3. Stimulant 1.Urinary tract disinfectant. 2. It is used in inflammatory conditions of urinary tract 3. Diuretic and diaphoretic. 4-Effective in varicose vein (Diosmin) Uses
Leaves containing volatile oils
4/25/2017 95 UsesConstituentsPlant 1. Astringent 2. For asthma 3. Antiseptic for respiratory tract infection 1. Volatile oil (cineole 50%) 2.Tannin. 3. Flavonoids. Eucalyptus 1. Astringent, 2. Antiseptic for respiratory tract and in cough mixtures 1. Volatile oil (cineole, limonene, pinene, and cadinol) 2- Flavonoids 4- Resin & tannin Guava
Eucalyptus leaves Guava leaves
Leaves containing Alkaloids
Atropa belladonna ‫الحسن‬ ‫ست‬ ‫أوراق‬ • Botanical Origin: • The dried leaves with or without the flowering tops of Atropa belladonna, Family: Solanaceae
• Shape: Simple oval to broadly ovate, narrow at the base and slightly decurrent. • Apex: Acute to acuminate • Margin: Entire • Surface: nearly glabrous • Petiole: short • Color: green to yellowish green. • Taste: Bitter and acrider • Stomata: Anisocytic • Ca-ox: Idioblasts or microsphenoidal crystals
• Hairs: • a-Glandular hairs: • 1- Clavate hair with 1-3 celled stalk and rounded or club shaped multicellular head. • 2- 4-6 celled stalk and 1 celled ovoid head. • b- Non-glandular hairs: • Uniseriate, 2-6 celled with thin walls and smooth cuticle.