been isolated from the mangrove endophytic fungusPhomopsissp. (Huang et al.
2010 ). Primary bioassays showed that compound 1 exhibited cytotoxicity against
Hep-2 and HepG2 cells with IC 50 values of 10 and 8μg/ml, respectively.
10.6 Conclusion
The injudicious use of plant biodiversity for human use, increased commercial and
scientific interests is continuously increasing the pressure on the population of
higher plants. India, despite being one of the global biodiversity hotspot, uncon-
trolled use of medicinal plants is leading to many valuable medicinal species at risk
of extinction. Globally, about 100,000 species of angiosperms are used for
medicinal purpose. However, because of overharvesting, irrational use and loss of
habitat about 15,000 species are near to extinction. Therefore, the sustainable use
and conservation of medicinal plant biodiversity is the need of time.
Endophytic microorganisms, by virtue of their ability to produce metabolites of
plant origin, can be of great significance to save fast diminishing plant biodiversity.
Microbial endophytes have been intensively studied in last decade because of their
potential to produce diverse biologically active metabolites of therapeutic impor-
tance. Their coevolution with host plant is thought to enable them to mimic host
chemistry. Isolation of potential endophyte followed by their successful laboratory
cultivation and scale-up are the important steps for exploring the endophytes for
biotechnological purpose. Of late, thousands of endophytic microorganisms have
been isolated, identified and their products such as steroids, alkaloids, peptides,
terpenoids, tannins, polyketones,flavonoids, and phenolics have been character-
ized. However, producing the metabolites of plant origin using endophytes has
several limiting factors. The laboratory cultivation conditions are completely dif-
ferent from that ofin plantaconditions. Moreover, the complex host–endophyte
relationship controls expression of genes coding for secondary metabolite pro-
duction. It is therefore concluded that, in spite of huge biotechnological potential,
endophytic microorganisms are relatively less explored microbial community that
can be tapped as rich source of bioactive metabolites of plant origin.
Acknowledgements Thefinancial assistance provided by SERB, DST, New Delhi, in terms of
fast track grant (File No. SR/FT/LS43/2012) to RHP, the fellowship from UGC, New Delhi under
its Maulana Azad National Fellowship for Minorities (MANF) scheme
(F1-17.7/2012-13/MANF-2012-13-MUS-MAH-13068/[SA-III/Website]) to SIM and financial
support from UGC, New Delhi and DST, New Delhi for strengthening the research facilities in the
School under the SAP-DRS (F.4-23/2015/DRS-II [(SAP II]) and FIST (SR/FST/LSI-433/2010)
programs, respectively are gratefully acknowledged.
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