Green Bio-Assisted Synthesis, Characterization and Biological Evaluation of Biocompatible ZnO NPs Synthesized from Different Tissues of Milk Thistle (Silybum marianum)

Abstract

The purpose of the current study was green synthesis of ZnO-nanoparticles (NPs) from different tissues of Silybum marianum (L.) Gaernt. (i.e., seeds, wild plant, in vitro derived plantlets and callus cultures) followed by extensive characterization and evaluation of their biological potency. ZnO-NPs thus synthesized were subjected to characterization using standard techniques such as XRD, FTIR and SEM. Thermal stability of synthesized NPs was also evaluated using thermo-gravimetric analysis. Highly stable crystalline NPs with size ranging between 30.8 and 46.0 nm were obtained from different tissues of S. marianum. These NPs have revealed a wide range of biological applications showing antioxidant, moderate α-amylase inhibitor, antibacterial and cytotoxic potencies. The highest antibacterial activity (20 ± 0.98 mm) was shown by seed extract-mediated ZnO NPs against Staphylococcus aureus (ATCC-6538). Seed extract-mediated ZnO NPs also showed the most potent antioxidant activity (27.7 ± 0.9 µgAAE/mg, 23.8 ± 0.7 µgAAE/mg and 12.7 ± 1.9% total antioxidant capacity (TAC), total reducing power (TRP) and DPPH-free radical scavenging assay (FRSA), respectively). All of the synthesized ZnO NPs also showed cytotoxic activity against the hepato-cellular carcinoma (HepG2) human cells. Interestingly, these ZnO NPs were also highly biocompatible, as evidenced by the brine shrimp lethality and human red blood cells hemolytic assays. Among all of the NPs synthesized and used, the effect of seed extract-mediated NPs was found to be most promising for future applications.

Characterization and biological activities of synthesized zinc oxide nanoparticles using the extract of Acantholimon serotinum

“…This is the first investigation to introduce the cytotoxicity of photosynthesized ZnO-NPs using methanol extract of A. serotinum against cancer and normal cell lines. Cytotoxicity and anticancer effects of biosynthesized ZnO-NPs using another plant extracts such as Punica granatum, Silybum marianum, Tectona grandis, Tamarindus indica, Nepeta deflersiana, and Albizia lebbeck also supported results obtained from this study [9,24,30,39,40,47]. Unfortunately, these findings suggest that the A. serotinum ZnO-NPs did not show specificity and selectivity toward the cancerous cells when compared with the normal cells; therefore, it is not selective enough to be useful as an anticancer compound.…”

“…Plants have some biomolecules and bio-reducing agents such as enzymes, proteins, flavonoids, terpenoids, and cofactors that provide a versatile, economical, and ecofriendly method to fabricate metal NPs. ZnO-NPs synthesis using whole-plant extract is reported in number of plants [8,9,30,[36][37][38][39][40][41][42][43][44].…”

“…Cytotoxicity of ZnO-NPs was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. For this, cells were exposed for 48 h to different concentrations (10,20,40,80,160,320, and 640 µg/mL) of ZnO-NPs. To detect the cell viability, 20 µL MTT solution was added to each well and incubated for 3 h. Then, the MTT solution was removed and 100 µL DMSO was added to each well followed by 15 min incubation.…”

Biosynthesis of zinc oxide nanoparticles by cell-biomass and supernatant of Lactobacillus plantarum TA4 and its antibacterial and biocompatibility properties

“…EA03 showed a lesser cytotoxic effect on the proliferation of A549 and MRC-5 cell lines at lower concentrations (10,25, and 50 µg/mL). In contrast, Abbasi et al 62 showed that the biosynthesized ZnO NPs displayed a maximum cytotoxic effect on hepatocellular carcinoma (HepG2) human cells at a lower concentration of 100 µg/mL. Nevertheless, our results revealed that the IC 50 value was more than 50 µg/mL compared to those chemically synthesized ZnO NPs 34,63,64 ; hence, considered as biocompatible to the cell line.…”

Influence of Zinc Oxide Nanoparticles and Char Forming Agent Polymer on Flame Retardancy of Intumescent Flame Retardant Coatings

“…The high-resolution SEM images show the presence of NPs. The SEM images show the agglomeration of the particles with narrow particle size distributions [29][30][31]. The NPs average size was found to be about 20 nm.…”