6. Anthraquinone Glycosides

Question 1

What are anthraquinone glycosides?

Answer 1

These are the glycosides with aglycones related to Anthracene group.

Question 2

Give the properties of these anthraquinone glycosides?

Answer 2

 Upon hydrolysis they yield aglycones that are di-, tri-, or tetrahydroxyanthraquinones or modifications
of these compounds.
 The free anthraquinone aglycones exhibit little therapeutic activity.
 The sugar residue facilitates absorption of aglycone.

Question 3

What are the therapeutic uses of anthraquinone glycosides?

Answer 3

The anthraquinone and related glycosides are stimulant cathartics and exert their action by increasing
the tone of the smooth muscle in the wall of the large intestine.

Question 4

Give anthraquinone biosynthesis?

Answer 4

Most anthraquinone glycosides aglycones are derived from the acetate pathway.

 It starts from acetic acid units which will form the active form acetyl Co-enzyme A

 Acetyl CoA will then form the malonyl Co-enzyme A by the addition of CO2 unit.

 Acetyl CoA and malonyl CoA form poly-keto-methylene-chain with simultaneous loss of CO₂ followed by cyclization to anthraquinone molecule (aglycone)

 A sugar molecule is added in Anthraquinone to form anthraquinoe glycoside

Question 5

What are the sources of these glycosides?

Answer 5

 Cascara Sagrada
 Aloe
 Rhubarb
 Cochineal
 Senna

Question 6

What is cascara sagrada?

Answer 6

Also known as Buckthorn.
 Cascara sagrada is the dried bark of Rhamnus purshianus.

Question 7

Which family does cascara belong to?

Answer 7

Rhamnaceae

Question 8

Explain the collection of cascara?

Answer 8

Collection: from 9-15 year old plant.
* Collection is made in summer season, one year before use.
*The bark is stripped from the tree by making longitudinal incisions.
* Sections are peeled off and rolled into large quills.
*The barks are sacked and dried under sun.
* Dried quills are then run through a “breaker” and broken into small pieces.

Question 9

What are the properties of cascara?

Answer 9

• Yellow or brown coloured bark
• Bitter and nauseatic taste
• No marked odour

Question 10

Give constituents of cascara?

Answer 10

O-glycosides (based on emodin) about 10 to 20%
 C-glycosides (Aloinlike) about 80 to 90% e.g, barbaloin and deoxybarbaloin (chrysaloin).
 Cascaroside A, B, C, D.

Question 11

Uses of cascara?

Answer 11

Cascara sagrada is a cathartic.
 Used in the correction of habitual constipation.

Question 12

What dose of cascara is used?

Answer 12

 Cascara sagrada fluidextract (bitter cascara),1 ml
 Aromatic cascara sagrada fluidextract (sweet cascara), 5 ml
 Cascara sagrada extract, 300 mg.

Question 13

What is aloe?

Answer 13

Aloe is the dried latex (juice) of the leaves
 Source: Aloe barbadensis (A. vera), A. ferox or Cape aloe

Question 14

Which family does aloe belong to?

Answer 14

Liliaceae

Question 15

Give collection of aloe?

Answer 15

During second year of life.
* Leaves are cut from base and processed for extraction of juice.
* Incision are given and cut leaves are placed in V-shaped vessels.
* The juice is collected and evaporated by drying on heat.
* Allowed to harden.

Question 16

What are the properties of aloe?

Answer 16

• Aloe occurs on the market as opaque masses
• Brownish black to dark brown in color
• Bitter taste
• Disagreeable smell
• Mainly alcohol soluble.

Question 17

Give constituents of aloe?

Answer 17

• Barbaloin (aloe-emodin)
• Aloinoside (O-glycoside)
• Chrysophanic acid
• A. babedensis contains 2.5 times as much barbaloin than Cape aloe.

Question 18

What is the use of aloe?

Answer 18

• As cathartic (not recommended)
• Aloe vera gel: The fresh mucilaginous gel present in the center of the leaves of
  A. barbadensis.
• Anti-inflammatory
• Antibacterial, burns, wounds, etc.
• Soothing and moisturizing effect
• Antiaging

Question 19

What is rhubarb?

Answer 19

Part used: dried rhizome and root.
 Sources: Rheum officinale, R. palmatum.

Question 20

Family of rhubarb?

Answer 20

Polygonaceae.

Question 21

Properties of rhubarb?

Answer 21

Yellow colour rhizome with small hairs
* Radish stems
*Taste astringent
* Characteristic odour

Question 22

Constituents of rhubarb?

Answer 22

• Rhein anthrones
• Anthraquinone derivatives (emodin, aloe-emodin, Rhein)
• Tannins

Question 23

Uses of rhubarb?

Answer 23

• As a cathartic
• Preparation of GIT for certain diagnostic procedures.
• Relieve stomach pain.

Question 24

Give the collection of rhubarb?

Answer 24

Rhizomes are collected from 6-15 years old plant.
* Rhizomes are taken out, slices are made.
* Drying of rhizomes under shade.

Question 25

What is the dose of rhubarb used?

Answer 25

• Dried rhubarb extract 20 to 50 mg/kg daily.

Question 26

What is cochineal?

Answer 26

 Dried female Insect that mainly feed on sap of cactus.
 Dactylopius austrinus (Order Hemiptera) feeds on Opuntia monacantha(Cactaceae)

Question 27

Give the collection of cochineal?

Answer 27

Insects are brushed, dried, ground and placed in boiling water.
* The coloured extract is then strained.

Question 28

What is the morphology of cochineal?

Answer 28

 Red coloured insect.
 Female insect is 2 mm in length and without wings.

Question 29

Constituents of cochineal?

Answer 29

 Carminic acid(10%) C-glycoside
 Fat (2%) and Wax (10%)

Question 30

What are the uses of cochineal?

Answer 30

• Used as dye and food colour
• To color pills and ointments

Question 31

What is senna?

Answer 31

Senna or senna leaves consists of the dried leaflet.
 Sources: Cassia acutifolia (Alexandria senna) and C. angustifolia (Tinnevelly senna)

Question 32

Give collection of senna?

Answer 32

cutting off the top of the plants about 15 cm above the ground
* Drying them in the sun
*The stems are separated from the leaflets by using sieves
*The leaves are then graded and packed in bags

Question 33

What are the properties of Senna?

Answer 33

 Senna is cultivated on wet lands resembling rice paddies
 The poorer grades of senna are grown on dry land without irrigation.
* Senna is graded according to the size of the leaf and the color of the leaflets
* Blue-green leaves are best
* Yellowish leaves are poorest.

Question 34

Give constituents of senna?

Answer 34

• Dimeric glycosides
• Sennosides A and B
• Sennosides C and D are minor constituents
• Small quantities of monomeric glycosides
• Free anthraquinones are also present
• Senna pods also contain useful, active glycosides

Question 35

What are the uses and dose of senna?

Answer 35

Senna is a cathartic.

The usual dose is 2g.