Chapter 9
Camptothecin: Occurrence, Chemistry
and Mode of Action
Mallappa Kumara Swamy, Boregowda Purushotham,
and Uma Rani Sinniah
Abstract Camptothecin (CPT), a planar pentacyclic ring system, constituting a
pyrrolo(3, 4-b)-quinoline group along with a-hydroxy lactone is observed mainly
from the plants that belong to the genus, Camptotheca. They tend to exhibit a
broad and significant clinical impact including antitumor, antiviral, antibacterial,
antipsoriasis, antirheumatic, antispasmodic, neurotropic, antimalarial activities, etc.
Due to their unique mode of action, CPT has a broad clinical interest. These agents
turn topoisomerase-I (top-I), an enzyme that exerts the torsional stresses of
supercoiled DNA into an intracellular poison. The CPTs stabilize the covalent
binding of top-I to its DNA substrates and the formation of these complexes tends
to the formation of reversible, single-strand nicks producing potentially lethal
double-strand DNA breaks resulting in apoptosis. Owing to high market value,
CPT-producing plant species have been scientifically explored in recent years. The
present chapter offers a comprehensive info on the sources, chemistry, and mode of
action of CPT.
Keywords Camptothecin Á Nothapodytes nimmoniana Á Anticancer compounds Á
Cytotoxicity Á Mode of action
9.1 Introduction
Bioactive natural compounds obtained from a wide-ranging medicinal plants have
gained more attention in the last few decades for treating numerous human health
issues. Several types of plant-derived compounds like phenolics, alkaloids, terpenoids, polyketides, and others are being already endorsed to have worthy clinical
M. K. Swamy (&) Á B. Purushotham
Department of Biotechnology, East West First Grade College, Bengaluru, India
e-mail: swamy.bio@gmail.com
U. R. Sinniah
Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, Darul Ehsan,
43400 Serdang, Malaysia
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
D. Pal and A. K. Nayak (eds.), Bioactive Natural Products
for Pharmaceutical Applications, Advanced Structured Materials 140,
https://doi.org/10.1007/978-3-030-54027-2_9
311
Camptothecin: Occurrence, Chemistry
and Mode of Action
Mallappa Kumara Swamy, Boregowda Purushotham,
and Uma Rani Sinniah
Abstract Camptothecin (CPT), a planar pentacyclic ring system, constituting a
pyrrolo(3, 4-b)-quinoline group along with a-hydroxy lactone is observed mainly
from the plants that belong to the genus, Camptotheca. They tend to exhibit a
broad and significant clinical impact including antitumor, antiviral, antibacterial,
antipsoriasis, antirheumatic, antispasmodic, neurotropic, antimalarial activities, etc.
Due to their unique mode of action, CPT has a broad clinical interest. These agents
turn topoisomerase-I (top-I), an enzyme that exerts the torsional stresses of
supercoiled DNA into an intracellular poison. The CPTs stabilize the covalent
binding of top-I to its DNA substrates and the formation of these complexes tends
to the formation of reversible, single-strand nicks producing potentially lethal
double-strand DNA breaks resulting in apoptosis. Owing to high market value,
CPT-producing plant species have been scientifically explored in recent years. The
present chapter offers a comprehensive info on the sources, chemistry, and mode of
action of CPT.
Keywords Camptothecin Á Nothapodytes nimmoniana Á Anticancer compounds Á
Cytotoxicity Á Mode of action
9.1 Introduction
Bioactive natural compounds obtained from a wide-ranging medicinal plants have
gained more attention in the last few decades for treating numerous human health
issues. Several types of plant-derived compounds like phenolics, alkaloids, terpenoids, polyketides, and others are being already endorsed to have worthy clinical
M. K. Swamy (&) Á B. Purushotham
Department of Biotechnology, East West First Grade College, Bengaluru, India
e-mail: swamy.bio@gmail.com
U. R. Sinniah
Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, Darul Ehsan,
43400 Serdang, Malaysia
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
D. Pal and A. K. Nayak (eds.), Bioactive Natural Products
for Pharmaceutical Applications, Advanced Structured Materials 140,
https://doi.org/10.1007/978-3-030-54027-2_9
311