Biology Reference
In-Depth Information
alkaloids, 7- hydroxy-3,4,5-trimethyl-6-on-
2,3,4,6-tetrahydroisoquinoline-8-carboxylic
acid and 2,5-dihydroxy-1-(hydroxymethyl)
pyridin-4-on, from endophytic fungi of
brotowali and studied their activity against
P. falciparum
.
Escherichia coli, Pseudomonas aeruginosa,
Salmonella typhimurium, Saccahromyces
cerevisiae
and
Candida albicans
. Vaz
et al.
(2012) isolated an endophyte
Colletotrichum
from leaves of
Myrciaria floribunda
and
Alchornea castaneifolia
, and an endophyte
Mycosphaerella
from
Eugenia
aff.
bimargin-
ata
. The authors also screened fungal endo-
phytes for antimicrobial activity against
pathogenic microorganisms. They reported
that 38 fungal extracts demonstrated anti-
microbial activity against at least one of
the different target microorganisms tested.
Emericellopsis donezkii
and
Colletotrichum
gloesporioides
showed the best MIC val-
ues, which were lower or similar to MICs
of known antibacterial and antifungal
drugs. Vieira
et al
. (2012) reported diver-
sity and antimicrobial activity of endophytic
fungi isolated from
Solanum cernuum
Vell. They revealed that the most abundant
taxa were closely related to
Arthrobotrys
foliicola, Colletotrichum gloeosporioides,
Colletotrichum
sp.
Coprinellus radian,
Glomerella acutata, Diatrypella frostii,
Mucor
sp.,
Phoma glomerata, Phoma mori-
cola, Phlebia subserialis
and
Phanerochaete
sordid
. In total 265 fungal extracts were
screened and 64 (26.01%) exhibited antifun-
gal and antibacterial activities. Gond
et al
.
(2012) isolated an endophytic fungus from
Nyctanthes arbor-tristis
and evaluated its
antimicrobial activity. The endophytic
Nigrospora oryzae
showed maximum inhibi-
tion against
Shigella
sp. and
Pseudomonas
aeruginosa; Colletotrichum dematium
and
Chaetomium globosum
exhibited a broad
range of antibacterial activity, including
inhibition of
Shigella flexnii, Shigella boydii,
Salmonella enteritidis, Salmonella para-
typhi
, and
P. aeruginosa
. The endophytic
C.
dematium
inhibited 55.87% of the radial
growth of the phytopathogen
Curvularia
lunata
. The authors suggested that antimi-
crobial activity of these endophytic micro-
organisms could be exploited in the
biotechnological, medicinal and agricultural
industries. Lu
et al
. (2000) isolated an endo-
phytic
Colletotrichum
species from
Artemisia
annua,
which is a traditional Chinese herb,
well recognized for its synthesis of artem-
isinin (an antimalarial drug). Further, they
5.2.4
Mycoendophytes with antifungal
and antibacterial activity
Endophytes have been proven to mimic
their host plant in the production of bioac-
tive molecules, which can be of enormous
pharmaceutical use (Table 5.1). A large
number of anticancer drugs, antimicrobials,
immunomodulators and many other useful
medicinal molecules have been isolated
from these endophytes. These microbes can
be a suitable alternative source of the bioac-
tive molecules usually isolated from their
hosts, some of which are on the verge of
extinction, and can also help in the conser-
vation of such endangered plant species.
Traditional medicinal use of plants in the
cure of ailments is one of the important cri-
teria behind the selection of hosts for isola-
tion of endophytic fungi. So far, many
antimicrobial compounds have been iso-
lated from endophytes belonging to several
structural classes such as alkaloids, pep-
tides, steroids, terpenoids, phenols, quinines
and flavonoids (Yu
et al
., 2010). The discov-
ery of novel antimicrobial metabolites from
endophytes is also an important alternative
to overcome the increasing levels of drug
resistance by plant and human pathogens.
The insufficient number of effective antibi-
otics against diverse bacterial species and
few new antimicrobial agents in develop-
ment is probably due to relatively unfavour-
able returns on investment.
Santiago
et al
. (2012) reported that an
endophytic fungus isolated from the plant
Cinnamomum mollissimum
showed anti-
fungal activity against
A. niger
and also anti-
cancerous activity. Budhiraja
et al.
(2012)
isolated
Aspergillus
and
Penicillium
spp.
from
Gloriosa superba
. They studied the
antimicrobial activity of these endophytes
against seven standard pathogenic strains:
Staphylococcus aureus, Bacillus subtilis,
Search WWH ::
Custom Search