© Benaki Phytopathological Institute
Endophytic fungi & secondary metabolites in medicinal plants
55
strated that all produce quinine and quini-
dine, as well as cinchonidine and cinchonine
(Maehara
et al
., 2011; Maehara
et al
., 2013).
Passiflora incarnata (Passifloraceae)
Passiflora consists of 500 species that
are found mostly in warm and tropical re-
gions.
Passiflora incarnata
leaves were found
to contain several active compounds, in-
cluding alkaloids, phenols, glycosyl fla-
vonoids, and cyanogenic compounds. The
major compounds present in
P. incarnata
are C-glycosyl flavonoids (vitexin, isovitex-
in, orientin and chrysin) and b-carbolinic al-
kaloids (harman, harmin, harmalin, harmol,
and harmalol). Among these natural prod-
ucts, chrysin has shown interesting biolog-
ical activities, including antibacterial, an-
ti-inflammatory, anti-diabetic, anxiolytic,
hepatoprotective, anti-aging, anticonvul-
sant and anticancer effects (Seetharaman
et
al
., 2017).
Three endophytic fungi identified as
Al-
tenaria alternata
,
Colletotrichum capsici
, and
C. taiwanense
were isolated from leaves of
P.
incarnata
and production of fungal chrysin
was confirmed through UV-vis spectrosco-
py, FT-IR, LC-ESI-MS, and
1
H
1
NMR analysis of
their extracts. The quantitative HPLC analy-
sis revealed that the yield of chrysin from
A.
alternata
was higher when compared with
previously reported bioresources (Seethara-
man
et al
., 2017).
Fritillaria cirrhosa D.Don (Liliaceae)
Bulbus
Fritillaria
have been used in tra-
ditional Chinese medicine for more than
2000 years, and at present, they are among
the most widely used antitussive and ex-
pectorant drugs. The major biological ac-
tive ingredients of Bulbus
Fritillaria cirrho-
sa
are steroidal alkaloids, such as peimisine,
imperialine-3β-D-glucoside, and peimine
(Wang
et al
., 2011).
Several dosens of endophytic fungi were
isolated from fresh bulbus of
Fritillaria uni-
bracteata
var.
wabensis
. One of these fungal
endophytes,
Fusarium redolens
6WBY3 was
capable of producing and secreting in the
culture medium peimisine and imperialine-
3β-D-glucoside whereas a second endo-
phytic fungus was found to secrete pei-
misine and peiminine. Interestingly, a large
number of the remaining endophytes were
able to produce large amounts of antioxi-
dants, such rosemarinic acid (Pan
et al
., 2014;
Pan
et al
., 2015; Pan
et al
., 2017).
Huperzia serrata (Thunb. ex Murray) Tre-
vis (Huperziaceae)
Huperzia serrata
is a traditional Chinese
herb medicine and has been extensively
used for the treatment of a number of ail-
ments, including contusions, strains, swell-
ings, schizophrenia, myasthenia gavis and
organophosphate poisoning. These phar-
maceutical applications of
H.
serrata
are
mainly due to its biologically active lycopo-
dium alkaloids. Among the lycopodium al-
kaloids, huperzine A (HupA) was found to
possess potent acetylcholine esterase inhi-
bition (AChEI) and is clinically used for the
treatment of Alzheimer’s disease (Zhao
et
al
., 2013). The content of HupA in the leaf is
richer than that in the stem and root of
H.
serrata
(Gu
et al
., 2005).
Several groups have isolated endophyt-
ic fungi from leaves, stems and roots of
H.
serrata
. Screening culture extracts of these
fungi for HupA production revealed that
most of HupA-producing fungi were iso-
lated from leaf tissues (Su
et al
., 2017). The
HupA-producing endophytic fungi belong
to
Penicillium griseofulvum
,
Penicillium
sp.,
Aspergillus flavus
,
Mycoleptodiscus
terrestris
,
Trichoderma
sp.,
Colletotrichum
gloeospori-
oides
strain ES026 and
Shiraia
sp.. The pro-
ductivity of these strains is less than 60-90
μg/L, with
Shiraia
sp. Slf14 being the best
producer (327.8 μg/L) (Su
et al
., 2017). Inter-
estingly, many
H. serrata
endophytic fungi
with AChE inhibitory activity did not contain
HupA in their extracts (Su
et al
., 2017; Wang
et al
., 2016) suggesting that some endophyt-
ic fungi produce new compounds with ac-
tivity against AChE.
Rhodiola spp. (Crassulaceae)
Rhodiola rosea
is a perennial herbaceous
plant that belongs to the family
Crassu-
