Collection & preparation of drug Digitalis

DEPARTMENT OF TECHNICAL EDUCATION ANDHRA PRADESH Name of the Staff : M. Padmavathi Designation : Assoc. Lecturer Branch : D. Pharmacy Institute : K.N.P.W. Year : D. Pharmacy I year Subject : Pharmacognosy Subject Code : PH-103 Topic : Collection & preparation of drug Duration : 50 Minutes Sub Topic : Digitalis Teaching Aids : PPT, Animations, Photographs

OBJECTIVES On completion of this period, you would be able to know The Biological source Cultivation Collection and Preparation for the market of Digitalis.

Known to Unknown DIGITALIS PLANT Fig.79.1

DIGITALIS FLOWERS Fig.79.2

Purple Foxglove (Digitalis purpurea) Fig.79.3

DIGITALIS LEAF SYNONYMS : BIOLOGICAL SOURCE : Digitalis Leaves, Foxglove Leaves BIOLOGICAL SOURCE : Digitalis consists of dried leaves of Digitalis purpurea belonging to the family Scrophulariaceae, dried at a temperature below 60oC, immediately after collecting the leaves. The leaves should contain not more than 5% of moisture.

Cultivation of Digitalis in an open field FARM VIEW Fig.79.4 Cultivation of Digitalis in an open field

DIGITALIS FLOWERS Fig.79.4

(Digitalis Purpurea) seedlings Fig.79.5

Observing the Seedlings Fig.79.6

HARVESTING OF DIGITALIS No leaves are to be used for medicinal purposes that are not taken from 2 year old plants. Leaves are picked when the bloom spike has run up and about two-third of flowers are expanded, because at this time before the ripening of the seeds, the leaves are in the most active state. They may be collected as long as they are in good condition.

HARVESTING OF DIGITALIS Only green, perfect leaves being picked. All those that are insect eaten or diseased or tinged with purple or otherwise discoloured must be discarded. Leaves from seedlings are valueless and they must also be collected in springs, before the plant flowers or in the autumn, when it has seeded as the activity of the alkaloids is in each case is too low.

PREPARATION FOR MARKET The fresh crop should if possible be delivered to the wholesale buyer the same day as cut. If this is impossible on account of distance, they should be picked before the dew falls in the late afternoon and dispatched the same evening. Packed loosely in wicker baskets lined with an open kind of muslin. Consignments by rail should be labeled “URGENT MEDICINAL HERBS” to ensure quick delivery. The weather for picking must be absolutely dry – no damp or rain in the air and leaves must be kept out of the sun and not packed too closely or they may heat and turn yellow.

PREPARATION FOR MARKET The odour of fresh leaves is unpleasant, the taste of both fresh and dried leaves is disagreeably bitter. Foxgloues have in some places been recklessly fathered by over- zealous and thoughtless collectors without due record to the future supply of the plants. The plant should not be roughly treated and never cut off just above the root, but the bottom leaves should in all cases be left to nourish the flower spikes in order that the seed may be ripened.

PREPARATION FOR MARKET The dried leaves as imported have occasionally been found adulterated with leaves of various other plants. The Chief of these are Inula conyza Inula helenium Symphytom officinale Verbascum thapsus Foxglove leaves are easy to distinguish by their veins running down the leaves.

CHEMICAL CONSTITUENTS Digitalis contains 0.2 to 0.45 % of Cardiac glycosides (Cardenolides), Purpurea glycosides A and B, which are primary glycosides. Digitalis also contains several other glycosides such as Odoroside H, Glucogitaloxin, Gitaloximn, Verodoxin and Glucoverodoxin.

CHEMICAL CONSTITUENTS The products of hydrolysis of purpurea glycoside A and purpurea glycoside B, the chief active constituents of the drug are as under Purpurea glycoside A Purpurea glycoside A enzymatic enzymatic hydrolysis hydrolysis Digitoxin + Glucose Gitoxin + Glucose hydrolysis hydrolysis Digitoxigenin + Digitoxose Gitoxigenin + Digitoxose

USES Digitalis increases excitability of Cardiac muscles and produces more powerful contractions. It is effective in Congestive cardiac failure to increase cardiac output and to relieve venous congestion. Hence it is described as a Cardiotonic. The improvement of circulation through kidney results in diuresis and loss of Oedema. The major disadvantage of Digitalis is that it has cumulative effect and therefore, in prolonged treatment one has to watch the patient carefully.

SUMMARY In this class we have discussed about cultivation, collection and preparation of drug to market along with Chemical constituents and uses of Digitalis

QUIZ 1.Digitalis leaf is synonymous to a) Henbane b) Fox glove c) Deadly night shade d) None of the above

QUIZ 2) Digitals belongs to a) Euphorbiaceae b) Rubiaceae c) Scrophularaceae d) Ranunculaceae

Frequently Asked Questions What are the other names of Digitalis? Write down the biological source of Digitalis. What are the chemical constituents of Digitalis? Which is the drug which is used as Cardio tonic? What is percentage limit of moisture that the drug should contain? How the harvesting of the drug done?

THANK YOU