This presentation is about alkaloids in plants ...it includes introduction about alkaloids ,types of alkaloids,structure ,classification and therapeutic uses of alkaloids

2.  INTRODUCTION
 CLASSIFICATION OF ALKALOIDS
 STRUCTURE AND TYPES OF ALKALOIDS
 THERAPEUTIC USES OF ALKALOIDS IN PLANTS

3.  Alkaloids are a group of naturally occurring chemical
compounds that mostly contain basic nitrogen atoms. This
group also includes some related compounds with neutral and
even weakly acidic properties.
 In addition to carbon, hydrogen and nitrogen, alkaloids may
also contain oxygen, sulfur and, more rarely, other elements
such as chlorine, bromine, and phosphorus.
 Alkaloids have a wide range of pharmacological activities
including antimalarial (e.g. quinine), antiasthma (e.g.
ephedrine),anticancer(e.g.homoharringtonine),antiarrhythmic
(e.g. quinidine), analgesic (e.g. morphine),antibacterial (e.g.
chelerythrine), and antihyperglycemic activities (e.g.
piperine).

4.  Compounds like amino acid peptides, proteins,
nucleotides, nucleic acid, amines, and antibiotics are
usually not called alkaloids.
 One of the oldest known alkaloids is opium, which is
an exudate obtained from poppy(papaver somniferon).
The use of opium mixed with wine to induce sleep and
it is also used as pain reliever.
 The name "alkaloids" (German: Alkaloide) was
introduced in 1819 by the German chemist Carl
Friedrich Wilhelm. and is derived from late Latin root
Latin: alkali (which, in turn, comes from the Arabic al-
qalwī – "ashes of plants") .

5.  Alkaloids were orginally defined as pharmocologically
active nitrogen containing basic compound of plant
origin.
 Alkaloids share three principal characters
1.They are soluble in water.
2.They possess atleast one nitrogen atom.
3.They exhibits high biological activity.
 Alkaloids are basically nitrogen bases .The amino acid
act as building blocks for the biosynthesis of alkaloids.
Majority of alkaloids contain a pyridine, quinoline and
isoquinoline or tropane nuclues and also alkaloids are
responsible for physiological effects in man and animals.

6.  Alkaloids have basic properties and are alkaline in
reaction. It turns red litmus paper to blue.
 More than 12,000 alkaloids have been found to occur in
approximately 20 percent of the species of flowering
plants, mostly herbaceous dicots.
FUNCTIONS OF ALKALOIDS IN PLANTS:
 Poisonous agents that protect the plants against insects,
fungus and predators.
 End products of Nitrogen detoxification.
 Regulate growth Factors.
 Reserve substances which can Supply nitrogen when
needed.

8. CLASSIFICATION OF ALKALOIDS:
 "True alkaloids", which contain nitrogen in the
heterocycle and originate from amino acids.
 Their characteristic examples are atropine, nicotine, and
morphine. This group also includes some alkaloids that
besides nitrogen heterocycle contain terpene (e.g.,
evonine or peptide fragments (e.g. ergotamine). This
group also includes piperidine alkaloids coniine and
coniceine although they do not originate from amino
acids.
 "Protoalkaloids", which contain nitrogen and also
originate from amino acids. Examples include
mescaline, adrenaline and ephedrine but this
protoalkaloids do not have nitrogen in its heterocycle
ring.

9.  Pseudoalkaloids – alkaloid-like compounds that do not
originate from amino acids. This group includes
terpene-like and steroid-like alkaloids, as well as
purine-like alkaloids such as caffeine, theobromine,
theacrine and theophylline.
 Those originate from the amino acid phenylalanine, but
acquire their nitrogen atom not from the amino acid but
through transamination.
 Some alkaloids do not have the carbon skeleton
characteristic of their group. So, galantamine and
homoaporphines do not contain isoquinoline fragment,
but are, in general, attributed to isoquinoline alkaloids.

13. THERAPEUTIC USES OF ALKALOIDS:
 Morphine a powerful and addictive pain killer, may
include upto 14% of the weight of high grade opium.
 The primary therapeutic use of nicotine is in treating
nicotine dependence in order to eliminate smoking with
the damage it does to health. Controlled levels of
nicotine are given to patients through gums, dermal
patches, electronic/substitute cigarettes or nasal sprays.
 Caffeine is widely used central nervous system
stimulant. Bronchopulmonary dysplasia in premature
infants for both prevention and treatment.
 Quinine is a traditional antimalarial agent used to treat
plasmodium falciparum strain.

14.  Papaverine, when injected in penile tissue causes direct
smooth muscle relaxation. Papaverine is used as an off
label prophylaxis (preventative) of migraine headaches.
 Cocaine is a tropical anaesthetic used as potent central
nervous system stimulant and as adrenergic blocking
agent.
 The yellow alkaloid Berberrine, isolated from barberry
shrub, shows antimicrobial and cytotoxic activity.
 Vinblastine is an antineoplastic used to treat Hodgkin’s
disease and other lymphomas.