Vol 12, Issue 3, 2019
Online - 2455-3891
Print - 0974-2441
ANTICANCER AND FREE RADICAL SCAVENGING POTENTIAL OF THE MARINE ALGICOLOUS
ENDOPHYTIC FUNGUS CLADOSPORIUM UREDINICOLA
VASAVI THIRUMALANADHUNI, LAVANYA LATHA YERRAGURAVAGARI
2
, VANI MATHAKALA
3
,
UMA MAHESWARI DEVI PALEMPALLI
4
Department of Applied Microbiology, Sri Padmavathi Mahilavisvavidyalayam, Tirupati – 517 502, Andhra Pradesh, India.
Email: vasavimicrobiology@gmail.com
Received: 08 December 2018, Revised and Accepted: 15 January 2019
ABSTRACT
Objective: The objective was to study the antioxidant and anticancer potential of the endophytic fungus Cladosporium uredinicola, isolated from the
marine brown alga Dictyota dichotoma.
Methods: Anticancer effect of the endophytic fungal extract was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT)
assay using MDA-MB-231 human mammary adenocarcinoma cells as in vitro cancer models. 3T3-L1 pancreatic adipocytes were used as in vitro
models for the evaluation of cytotoxic activity against normal cells using MTT assay. Free radical scavenging activity was assessed by 2, 2-diphenyl-1-
picrylhydrazyl (DPPH) assay.
Results: The ethyl acetate extract of the endophytic fungus showed potent cytotoxic activity against MDA-MB-231 human breast adenocarcinoma
cell lines with an inhibitory concentration (IC
50
) value of 373 µg/ml and a very mild cytotoxic effect on 3T3-L1 Cells with an IC
50
value of 2403 µg/ml.
DPPH free radical scavenging assay of the extract showed an IC
50
value of 359 µg/ml indicating its potential free radical scavenging activity.
Conclusion: The results indicated that the endophytic fungus C. uredinicola, isolated from the marine brown alga D. dichotoma, acts as a potential
source for anticancer and antioxidant metabolites. Moreover, these anticancer metabolites were observed to be less toxic to the normal cells, which
make them prospective therapeutic agents.
Keywords: Marine endophytic fungi, Free radical scavenging, Cytotoxic, MDA-MB-231,3T3-L1 cells.
INTRODUCTION
Marine environment is considered to be a reservoir of pharmaceutically
important bioactive compounds due to its rich biodiversity and
extreme physical and chemical conditions. In recent years, a number of
bioactive compounds were isolated from the marine organisms such as
sponges, seaweeds, and microorganisms. Some of these compounds are
under pre-clinical and clinical trials [1]. More than 10,000 secondary
metabolites were reported to be isolated from marine organisms [2].
Some anticancer compounds such as “hemiasterlin” from the sponges
and “elisidepsin” from molluscs are under clinical trials [3].
Marine microorganisms are more advantageous than other marine
organisms since they can be cultured and manipulated in the laboratory
very easily. Several marine bacteria, Actinomycetes, and fungi were
screened for bioactive metabolites [4]. Antifungal compounds such as
basilikamides A and B, anticancer compounds such as bacillistatins 1
and 2, and antioxidant compounds such as wentiquinone were reported
from the marine microorganisms [2].
Among several marine microorganisms, marine endophytes are largely
unexplored due to the problems associated in culturing them. Endophytes
reside in the living tissues of the host without causing any apparent
harmful effect. These peculiarities of lifestyle compel them to encounter
host defense molecules continuously. It is that, due to this complexity,
the endophytes were evolved to produce various unique metabolites,
which could be exploited for pharmaceutical applications [5].
Cancer is one of the leading causes of mortality and morbidity worldwide.
According to the definition given by the World Health Organization,
cancer is a generic term for a large group of diseases that can affect any
part of the body in which there is a rapid creation of abnormal cells that
grow beyond their usual boundaries and invade adjoining parts of the
body and spread to other organs. The American Cancer Society reported
cancer as the second most common cause of death next to cardiovascular
diseases in the USA and Europe. Resistance to anticancer compounds
and side effects of the drugs are the major problems associated with
chemotherapy. In this context, there is an urgent need to develop new
and safe drugs for cancer treatment. In the past 20 years, an increasing
number of pharmaceutically useful compounds were reported [3].
Of the eight marine drugs approved for various purposes, five
compounds, namely cytarabine, ziconotide, trabectedin, eribulin
mesylate, and brentuximab, have been approved for cancer
treatment [6]. With this background, the present study was carried
out to evaluate the free radical scavenging and anticancer potential
of the marine algicolous endophytic fungus Cladosporium uredinicola
isolated from the marine brown alga Dictyota dichotoma. In this study,
the antioxidant activity was screened by 2, 2-diphenyl-1-picrylhydrazyl
(DPPH) free radical scavenging assay, whereas cytotoxic activity on
both cancer and normal cells was evaluated by 3-(4, 5-Dimethylthiazol-
2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay.
METHODS
Chemicals
Ethyl acetate (EA) was obtained from SD Fine-Chem Limited, Mumbai,
India. DPPH, MTT, Dulbecco’s Modified Eagle’s Medium (DMEM),
phosphate-buffered saline, trypsin - HyClone, and ciprofloxacin (cell
culture) were procured from HiMedia Laboratories, Mumbai, India.
Medium for culturing of endophytic fungi
A novel medium by name “MGM medium” (patented) was formulated
for culturing of endophytic fungi [7].
© 2019 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons.
org/licenses/by/4. 0/) DOI: http://dx.doi.org/10.22159/ajpcr.2019.v12i3.30977
Research Article