MORPHO ANATOMICAL STUDIES OF LEAVES OF Urena ... - IJPI

INTERNATIONAL JOURNAL OF 

RESEARCH ARTICLE 

PHARMACEUTICAL INNOVATIONS ISSN 2249-1031 

MORPHO ANATOMICAL STUDIES OF LEAVES OF Urena lobata 

Linn. 

Rinku Mathappan 1* , Sanjay P.Umachigi 2 

1 Shri Jagdishprasad Jhabarmal Tibrewala University, Jhunjhunu (Raj.) 

2 Shilpa Medicare Ltd, Modavalasa Village, Denkada madalam, Vizianagaram, (A.P) 

Abstract 

Urena lobata Linn belonging to the family of Malvaceae commonly known as Caesar weed, 

which is distributed throughout India. This herb is under shrub category of 60 to 100 cm in 

length and tomentum in nature. The plant contains flavonoids and flavonoid glycoside, 

alkanes, β-sitosterol and stigma sterol from the whole plant. Various extracts of the leaves 

and roots are used in herbal medicine to treat diverse ailments such as cough, malaria, 

venereal diseases, wounds, toothache, and rheumatism. The present paper evolves the 

exomorphological, histological and powder microscopical studies on the leaves of Urena 

lobata linn. 

Key words: Urena lobata Linn, Exomorphology, Pharmacognosy, Photomicrographs, 

Powder microscopy 

Introduction 

The use of medicinal plants as a 

foundation to cure the diseases can be 

traced reverse more than five millennia to 

on paper credentials of the early 

civilizations in China, India and Near East 

and is an art as old as mankind without a 

doubt. Even today medicinal plants are the 

almost exclusive source of drugs for the 

majority of the world’s population helps to 

relief from illness. Nature has been the 

good architect of compounds for thousands 

of years and a variety of plants with 

therapeutic properties is quite amazing. It 

is predictable that approximately 70,000 

plant species from lichens to gigantic trees 

have been used at one time for medicinal 

purposes. The entire useful crude drugs 

Volume 3, Issue 1, Jan. − Feb. 2013 

have been thoroughly studied botanically 

and histological thus botanically oriented 

sciences of Pharmacognosy became 

stagnant. 

The plant Urena lobata Linn of Malvaceae 

family is an erect herbaceous or semi 

woody, tomentose under shrub growing 

60-100 cm or more height. The young 

stem and branches are covered with a bit 

of harsh scattering stellate hairs and 

bearing simple, interchange uneven largely 

ovate to round cordate, diagonal or lobed 

leaves and sessile or shortly stalked 

pinkish auxiliary flowers. Leaves are 

*Corresponding Author 

Rinku Mathappan 

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simple, alternate, petiolate, stipulate; 

blade-very variable, usually broader than 

long round or ovate, up to 10-15 cm long 

and cordate at the base angled or shallowly 

5-7 lobed. 

The lobes not extending half way down or 

occasionally nearly obsolete generally 

acute or acuminate, serrate, stellately 

tomentose on both surface but paler 

beneath with five to seven pairs of basal 

nerves which are prominent on the under 

surface and with a large gland below at the 

base of the midrib and sometimes at the 

base of two lateral also. Habitually the 

plant being used as febrifuge, diuretic and 

rheumatism. Moreover mainly useful for 

toothache, wounds, gonorrhea and used as 

food for animals and humans [1-2] . The 

different extracts of the leaves and roots of 

Urena lobata Linn are used to treat diverse 

ailments such as cough, malaria, venereal 

diseases and rheumatism. The leaves and 

flowers of Urena lobata Linn are eaten as 

famine food in Africa. 

The main constituents of Urena lobata 

Linn, includes flavonoids, flavonoids 

glycosides, β-sitosterol, stigmasterol, 

furocoumarin, imperatorin, mangiferin and 

quercetin [3] . Also it contains kaempferol, 

luteolin, hypolatin and gossypetin [4] . 

Herbal drugs are required to be exploited 

more and more and to a great extent use of 

natural drugs all over the world in modern 

era is an indication of significant 

contribution of pharmacognosy to modern 

system of medicine. The main purpose of 

pharmacognostial study was to determine 

exomorphology, pharmacognosy, and 

powder microscopy. microscopical 


parameter present in the leaves of Urena 

lobata Linn 

MATERIALS AND METHODS 

Collection and authentification 

The plant materials Urena lobata Linn 

were collected from the Herbal Garden 

Division of Kerala Ayurveda Ltd, Aluva 

and authentified. A specimen voucher was 

deposited in college herbarium for future 

references. 

Preparation of specimen 

Great care has taken to choose the healthy 

plants and normal organs. The specimens 

of leaf was cut and removed from the plant 

and fixed in a solution mixture containing, 

formalin A (5mL), acetic acid (5mL) and 

ethyl alcohol (70%, 90 mL) for 24 h. After 

fixing the specimens were dehydrated with 

graded series of tertiary-butyl alcohol [5] . 

Further the infiltration of the specimens 

was carried out by gradual addition of 

paraffin wax at 58-60 °C until tertiarybutyl 

alcohol solution attained super 

saturation. Finally they obtained paraffin 

blocks were used for sectioning. 

Sectioning 

The paraffin embedded specimens were 

sectioned with help of Senior Precision 

Rotary microtome (MT-1090A, by 

WESWOX, India) dewaxing of the 

sections was done by normal procedure [6] . 

After dewaxing, the thickness of the 

sections was 10-12 µm and stained with 

toluidine blue (polychromatic stain) [7] . 

The staining results were remarkably good 

and some cytochemical reactions were also 

obtained. The dye rendered pink colour to 

the cellulose walls blue to the lignified 

cells, dark green to suberin, violet to the 

mucilage, blue to the protein bodies etc. 

Wherever necessary the sections were also 

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stained with safranin, fast-green and iodine 

solution for the identification starch. 

For stomatal morphology, venation pattern 

and trichomes distribution, paradermal 

sections of leaf was taken cleaned with 

sodium hydroxide solution (5%) and 

epidermal peeling by partial maceration 

(Jeffrey’s maceration fluid). Temporary 

preparations of the above macerated / 

cleared materials were made with 

glycerine. The powdered materials of 

different parts of the plants were collected 

and cleared with NaOH and mounted in 

glycerin medium after staining (described 

previously) for better clarity. 

Photomicrographs 

Microscopic photographs of tissues of 

different magnifications were taken Nikon 

lab photo 2 microscopic units. For normal 

observations bright field was used and for 

crystals, starch grains and lignified cells 

polarized light was employed. Since these 

structures have birefringent property, 

under polarized light they appear bright 

against dark background. The 

magnifications of the figures were 

indicated by the scale-bars [8-9] . 

RESULTS AND DISCUSSION 

Exomorphology 

Leaves were simple, alternate, petiolate, 

stipulate, usually broader than long round 

or ovate, up to 10-15 cm long, cordate at 

the base angled or shallowly 5-7 lobed and 

not extending half way down or 

occasionally nearly obsolete generally 

acute or acuminate, serrate, stellately 

tomentose on both surface. But paler 

beneath with five to seven pairs of basal 

nerves which are prominent on the under 

surface with a large gland below at the 


base of the midrib and sometimes at the 

base of two lateral also. The petiole was 

variable in length and the stem was 

moderately thick, pubescent in young ones 

and smooth in mature ones with long inter 

nodes. The root system consists of taproot 

and several branching lateral roots were 

stout and brown in colour. The diameter 

was varied between 5-6 mm and the length 

ranged from 20-25cm. Very small wiry 

cream colour rootlets arise from the lateral 

roots. Small lenticels are also present 

towards the base and the outer surface of 

the root (Fig1). 

Fig 1. Exomorphic features of the plant 

Urena lobata Linn 

1). Habit profile, 2). A twig with axiliary 

flower, 3). A portion of tap root system 

Anatomy of the leaf 

The leaf is the thin and dorsi-ventral (Fig 2 

A&B) and lamina has trichomes on both 

sides. The adaxial epidermis has larger 

cells than the abaxial layers. The 

mesophyll is differentiated in to upper 

palisade zone and lower spongy 

parenchyma zone (Fig 2 C&D). The 

midrib is prominent and projects equally 

on the upper and lower side in the form of 

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broad hemispheres as of narrow areas of 

collenchymas occur on the adaxial and 

abaxial part of the midrib. The vascular 

strand single collateral, with an arc of 

sclerenchyma cells adjacent to the phloem 

[Fig 2(1&2)]. Sessile, stellate trichomes 

with seven or more hairs arising from 

rosettes of epidermal cells are frequent on 

petiole and leaf (Fig 2 C&D). The stomata 

are paracytic and the epidermal cells are 

wavy (Fig 3 A&B) and (Fig 4 A&B). 

Ads: Adaxial side, AdE: Adaxial 

Epidermis, AbE:-Abaxial Epidermis, Ep: 

Epidermis, 

Col: Collenchyma, GT: Ground Tissue, 

La: Lamina, MR: Midrib, Sc: 

Sclerenchyma, VB Vascular Bundle, SM: 

Sponge Mesophyll, Ph: Phloem, PM: 

Palliside Mesophyll, Tr: Trichome, X: 

Xylem 

Fig 2. Anatomy of the leaf of Urena 

lobata Linn 

A: - Transvers section of Leaf, 

B:- Transvers section of Leaf through 

Midrib, 

C& D: - A portion of Lamina showing 

Trichomes 

Fig 3. Enlarged epidermal Trichomes 

A: - Rosette basal cells of the epidermal 

trichomes, 

B: - Stellate trichomes magnified 

Ar: Arm, RC: Rosette Cell, BC: Basal 

Cell 


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sclerenchyma cells both on the outer and 

inner phases of each vascular bundle (Fig 

5B). The petiole along the distal region in 

quite different from the basal part. It is 

perfectly circular in cross selection with 

stellate trichomes at certain places (Fig 

5A). The epidermis is followed by 

homogeneous parenchymatous tissue. 

Some of the parenchyma cells are 

tanniferous.The vascular tissues are 

organized in to a continuous cylinder 

enclosing sclerenchymatous pith. Xylem 

elements occur in radial rows and phloem 

occurs in continuous zone with peripheral 

phloem fibers (Fig 5A). 

Fig.4 Leaf paradermal section of 

stomata 

A: - Leaf paradermal section showing 

stomata, 

B: - Leaf paradermal section showing 

stomata and epidermal trichomes. 

Ec; Epidermal cell, ETr: Epidermal cells 

of the Trichomes, St: Stomata 

Anatomy of the Petiole 

Structure of petiole at distal and proximal 

parts were studied .Along the proximal 

region is dorsiventrally differentiated .The 

adaxial side is shallowly concave and the 

abaxial side is circular (Fig 5A).The 

epidermis is followed by 2 or 3 layers of 

collenchyma and the rest of the ground 

tissue is parenchymatous. The vascular 

strands are differentiated to abaxial 

medium strand, three lateral stands and a 

smaller adaxial strand. Each vascular 

strand is collateral consisting of outer 

phloem, inner xylem and a patch of 


Fig 5. Transverse Section of Petiole, 

5 (A) Petiole Distal region, 

5 (B) Petiole Proximal regions 

Col:- Collenchyma, Ep:- Epidermis, GT:- 

Ground Tissue, AdB:- Adaaxial Bundle, 

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Sc:- Sclerenchyma, LB:-Lateral Bundle, 

Ph:-Pholem, Tr:-Trichome, X:-Xylem, 

Pa:-Parenchyma, MB:-Median Bundle 

Venation pattern 

The vein-lets are prominent, forming, 

distinct, polygonal. The vein-terminations 

are distinct, short thick and unbranched; 

the islets are random in orientation (Fig 

6A). Along the vein calcium oxalate 

druses are located in regular uniseriate 

row. The crystals are spherical, spiny 

bodies of 30 μm in diameter (Fig.6B). 

type and are long, narrow, tapering 

towards the tip. The cell walls are fairly 

thick and smooth. The trichomes have no 

cell inclusions with 1.05 mm long and 30 

µm in thickness. 

Fig 6. Venation pattern of Urena lobata 

Linn leaf 

A:- Vein islets and vein termination, 

B:- Crystals along the vein under 

polarized light microscope. 

Cr:- Crystals, VI:- Vein Islets. VT:- 

Vein Terminology 

Powder Analysis 

The leaf powder of Urena lobata Linn was 

greenish in colour, with punget odour and 

characteristic taste. Powder analysis 

observation cited that Non glandular 

trichomes and A cluster of trichomes (Fig7 

A&B). Epidermal trichomes are presented 

as unicellular and unbranched in the 

powder .The trichomes are non glandular 


7. Powder microscopy of trichomes 

A. Non glandular Trichomes, B. Cluster 

of Trichomes 

Fragments of fibers which are thick, 

narrow and wide (Fig 8 A, B&C). 

Parenchyma cells are wide and narrow, 

elongated, rectangular and thick walled 

seen in isolated condition. They have thick 

cellulose walls and wide circular simple 

pits. The cells are 250-350 µm long and 

30-70 µm wide. Fibers (xylem) widely 

spread in the powder. They are long and 

thin in the middle and gradually tapering 

the ends. The walls are thick and lignified 

and the pits on the walls are not evident. 

Some of the fibers are narrow and others 

are wide 

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A:- Tailed vessel element, B:- Vessel 

element, C:- Vessel element and fibres 

Fi:- fibres, Pe:-Perforation, Pi:- Pits, VE:- 

Vessel Element. 

Fig 8. Fibers of Urena lobata Linn leaf 

A: - Parenchyma cells-(Enlarged), B:- 

Narrow fibres, C:- Wide fibres 

NF: - Narrow Fibre, Pa: - Paraenchyma 

cells, WF: - Wide Fibre 

Vessel elements of Urena lobata Linn 

leaf is shown in (Fig 9. A, B & C). The 

vessel elements are long, narrow and 

cylindrical. Their walls are fairly thin. 

The pits on the lateral walls are wide, 

circular, either oblique or horizontal in 

orientation. The vessel elements are 350- 

600 µm long and 50µm wide. 

Fig 9. Vessel elements of Urena lobata 

Linn leaf 

CONCLUSION 

The present study on pharmacognostical 

studies on Urena lobata Linn includes the 

exomorphology histological and powder 

microscopical evaluation of the leaves. 

This provides helpful information with 

regards to its correct identity and to 

differentiate from other closely related 

species. The study of microscopic 

characters of the plant shows the presences 

of identifying characters which help for the 

future works on Urena lobata Linn. 

REFERNCES 

1. Pharmacognosy of Ayurvedic 

drug,Department 

of 

Pharmacognosy,University of 

Kerala,1962, Vol 5;108-112. 

2. Mazumder U.K, Gupta M, 

Manikandan.L, Bhattacharya S, 

Methanolic extract of Urena lobata 

root for its antibacterial activity, 

Fitoterapia, 2001; 72-927. 

3. Keshab Gosh A. furcoumarin, 

Imperatorin isolated from Urena 

lobata (Malvaceae) Molbank, 

2004; 382. 

4. The Wealth of India, A dictionary 

of Indian Raw Materials and 

Industrial product, NISCAIR, 

Council of Scientific and Industrial 

Research Press, India, Revised 

Edition Reprinted, CSIR New 

Delhi 2004,Vol 5;284 


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5. Sass, J.E, Elements of Botanical 

Microtechnique, McGraw Hill 

Book Co, New York, 1940; 222. 

6. Johansen,D.A., Plant Micro 

technique,Mc Graw Hill Book Co; 

New York,1940;523. 

7. O’Brien, T.P Feder, N. and Mc 

Cull,M.E, Polychromatic staining 

of plant cell walls by toluidiblue- 

O, Protoplasma,1964,59;364-373. 

8. Easu,K, .Plant anatomy John Wiley 

and sons, New York,1964;767. 

9. Easu.K, Anatomy of seed Plants, 

John Wiley and sons, New York; 

1979;550. 


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MORPHO ANATOMICAL STUDIES OF LEAVES OF Urena ... - IJPI

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