Biogenesis of silver nanoparticles using endophytic fungusPestalotiopsis microsporaand evaluation of their antioxidant and anticancer activities.
An endophytic fungal strain isolated from the leaves ofGymnema sylvestrewas identified asPestalotiopsis microsporaVJ1/VS1 based on nucleotide sequencing of internal transcribed spacer region (ITS 1-5.8S-ITS 2) of 18S rRNA gene (NCBI accession number KX213894). In this study, an efficient and ecofriendly approach has been reported for the synthesis of silver nanoparticles (AgNPs) using aqueous culture filtrate ofP. microspora. Ultraviolet-visible analysis confirmed the synthesis of AgNPs by showing characteristic absorption peak at 435 nm. Fourier transform infrared spectroscopy analysis revealed the presence of phenolic compounds and proteins in the fungal filtrate, which are plausibly involved in the biosynthesis and capping of AgNPs. Transmission electron microscopy (TEM) showed that the AgNPs were spherical in shape of 2-10 nm in size. Selected area electron diffraction and X-ray diffraction studies determined the crystalline nature of AgNPs with face-centered cubic (FCC) lattice phase. Dynamic light scattering analysis showed that the biosynthesized AgNPs possess high negative zeta potential value of -35.7 mV. Biosynthesized AgNPs were proved to be potential antioxidants by showing effective radical scavenging activity against 2,2'-diphenyl-1-picrylhydrazyl and H2O2radicals with IC50values of 76.95±2.96 and 94.95±2.18 µg/mL, respectively. The biosynthesized AgNPs exhibited significant cytotoxic effects against B16F10 (mouse melanoma, IC50=26.43±3.41 µg/mL), SKOV3 (human ovarian carcinoma, IC50=16.24±2.48 µg/mL), A549 (human lung adenocarcinoma, IC50=39.83±3.74 µg/mL), and PC3 (human prostate carcinoma, IC50=27.71±2.89 µg/mL) cells. The biosynthesized AgNPs were found to be biocompatible toward normal cells (Chinese hamster ovary cell line, IC50=438.53±4.2 µg/mL). Cytological observations on most susceptible SKOV3 cells revealed concentration-dependent apoptotic changes that include cell membrane blebbing, cell shrinkage, pyknotic nuclei, karyorrhexis followed by destructive fragmentation of nuclei. The results together in this study strongly provided a base for the development of potential and versatile biomedical applications of biosynthesized AgNPs in the near future.
Department of Biotechnology, Sri Venkateswara University, Tirupati.
Vasudeva Reddy
VR
Netala
Biology Division, Indian Institute of Chemical Technology, Hyderabad; Academy of Scientific and Innovative Research, New Delhi.
Murali Satyanarayana
MS
Bethu
Department of Biotechnology, Sri Venkateswara University, Tirupati.
Bobbu
B
Pushpalatha
Department of Bioinformatics.
Vijaya Bhaskar
VB
Baki
Department of Biotechnology, Sri Venkateswara University, Tirupati.
Sani
S
Aishwarya
Biology Division, Indian Institute of Chemical Technology, Hyderabad.
J Venkateswara
JV
Rao
Department of Botany, Sri Venkateswara University, Tirupati, India.
Vijaya
V
Tartte
D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D016466:CHO Cells; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D053768:Metal Nanoparticles; D051379:Mice; D012834:Silver / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D013098:Xylariales / Q000378:metabolism*
D000970:Antineoplastic Agents; D000975:Antioxidants; D012834:Silver
18S rRNA; AO-EB staining; AgNPs; B16F10; Pestalotiopsis microspora; SKOV3