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Streptmyces and natural productsOnly 14 pages are availabe for public view
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Abstract
Chemotherapy is one of the main treatments used to combat cancer. A
great number of antitumor compounds are natural products or their
derivatives, mainly produced by microorganisms. In particular,
streptomycetes are the producers of a large number of natural products with
different biological activities, including antitumor properties. These
antitumor compounds belong to several structural classes such as
anthracyclines, enediynes, indolocarbazoles, isoprenoides, macrolides, nonribosomal
peptides and others, and they exert antitumor activity by inducing
apoptosis through DNA cleavage mediated by topoisomerase I or II
inhibition, mitochondria permeabilization, inhibition of key enzymes
involved in signal transduction like proteases, or cellular metabolism and in
some cases by inhibiting tumor-induced angiogenesis. Streptomycetes have
attracted special attention in the last years for their ability to produce
interesting pharmacological lead compounds.
This study aimed to evaluate the antitumor activity of metabolites from
Streptomyces as antitumor activity using both in vitro and in vivo studies.
The Streptomyces were purely isolated from the soil samples that collected
from various location in Tamalay Menoufia . Then the Streptomyces were
recultured successive times and processed to obtain their extracts. Twenty
Streptomyces extracts were obtained. Two isolates of Streptomyces were
characterized morphologically, physiologically, biochemically and 16sr
RNA and they named Streptomyces Tamalay strain Ag18 and Streptomyces
Tamalay strain Ag 20. Twenty four female albino mice were used in the
present study. The mice were divided into 4 groups (6 of each). The 1st
group was Control, injected subcutaneously with an isotonic saline solution.
The 2nd, group injected subcutaneously with Ehrlich ascites tumor cells
(EAC).