| dc.description.abstract | Ficus plants are known for their therapeutic benefits and symbolic significance
in religion and culture. They have played a significant role in ancient indigenous
medical methods, such as Ayurveda, Siddha, Unani, and Homoeopathy. The fruit of
various Ficus plants, particularly the fig Ficus carica, is rich in antioxidants and
health-benefitting polyphenols. Members of this genus contribute to various
medicines in ayurveda, such as "Pancha Valkala Kashaya". However, most research
focuses on a small number of plants, so there are a number of Ficus species that are
overlooked. Ficus drupacea Thunb. and Ficus exasperata Vahl, comes under this type
of plants. The present study encompasses two different phases and each phase contain
various parts. The first phase contains major three parts such as phytochemical
profiling, bioactivity studies and silver nano particle’s formulation. The second phase
contain three parts in which isolation and identification of the fruit fungal endophytes
from the two species is the first part, biochemical analysis of the fruit fungal
endophytes comes as the second part and nanoparticle biosynthesis and associated
studies is the third part.
Phytochemical assays were conducted as two part using preliminary studies
with three solvents based on their polarity viz hexane, methanol and water. Polar
solvents were good at eluting various phytochemical groups and so among the polar
solvents water was selected due to its nontoxic nature towards biological system.
Phytochemical delineation of the four aqueous extracts such as leaf and fruit of F.
drupacea and F. exasperata revealed ninety-two non-volatile and ten volatile
compounds, which falls under the major phytochemical groups, alkaloids, phenols,
terpenoids, glycosides etc. Major two activities such as antioxidant and anticancer
activities were studied using the extracts. In the antioxidant study four important in
vitro antioxidant assays such as DPPH radical scavenging assay, hydroxyl radical
scavenging assay, nitric oxide scavenging assay and superoxide radical scavenging
assays were conducted. Even though concentration dependent variation, ie., (an
increasing percentage inhibition with increasing extract concentration) was reported,
over all ability to scavenge free radicals seems to be moderate with the four-extracts
used in the study. Anticancer activity was also tested using the four aqueous extracts
on MCF-7 breast cancer cell lines. Toxicity studies were also conducted on the normalcell line L929 to assess the ability of the extract to distinguish and save the normal
cells while harming only the cancer cells. Anticancer assay revealed potential
anticancer activity with the four extracts. Among the four extracts, F. drupacea fruit
extract was found to be very effective with its anticancer ability specifically to target
the cancer cells and giving least cytotoxic effects on the normal cell lines. This extract
was chosen for further studies. Apoptosis detection was done using double stain
method as well as comet assay. The study revealed that the cause of antiproliferative
action was due to apoptosis but not necrosis. Studies continued to analyze the ability
of the fruit extract in causing cell cycle arrest and gene modulation. Cell cycle arrest
was reported with the G1 phase which was supported by the cell cycle regulation assay
by flow cytometry. The gene expression studies on both p53 and STAT 3 further
confirmed the anticancer activity of the cells with increased expression of P53 and
down regulation of STAT 3 which were the basis of apoptosis and cell cycle arrest.
The third part of the first phase was bio fabrication of nanoparticle from the
four aqueous extracts (leaf and fruit extracts of F. exasperata and F. drupacea). Silver
nanoparticles were readily synthesized from the four-extract considered in the current
study. Visual indication of colour change was further confirmed by the UV-vis
spectroscopy as well as SEM imaging. The nanoparticles biosynthesized were able to
produce a constitutive peak for silver in the UV- vis range and nearly spherical shaped
nanoparticles that falls under the size range of 20-50 nm were produced. When these
nanoparticles were tested for their antimicrobial efficacy, they seem to be better
antimicrobial agents in the higher concentration and they could produce zone of
inhibition nearly comparable to the positive control used in the study.
In phase two the study revealed the presence of fungal endophytes from the
two plants both from fruits and leaves. 11 fungal endophytes were isolated from the
leaves and fruits. Fruits were reported to have a single endophyte which is similar for
both F. exasperata as well as F. drupacea. All the 10 fungal endophytes from the
leaves of both plants were identified to the species level using the BLAST analysis
based on ITS and LSU region. All the fungal isolates were from the division
Basidiomycota and Ascomycota. Fruit fungal endophyte of F. drupacea was
subjected to phytochemical profiling and 34 compounds were reported. This fungal
extract was used in the synthesis of gold and silver nanoparticles. These nanoparticles
were found to have anti-microbial action against two gram negative bacteria E. coli
and Salmonella paratyphi. | en_US |
