Zahra Hashemi

Background: Hypoxia exists in some malignancies and is a prognostic risk factor contributing to tumor growth and metastasis. Anti-hypoxic compounds may improve this situation and be considered as anti-cancer agents. In previous reports, Cydonia oblonga, Portulaca oleracea, and Artemisia dracunculus showed anti-cancer activities. So, we investigated the anti-hypoxic activities of C. oblonga, P. oleracea, and A. dracunculus to evaluate the possible mechanism of their effectiveness in treating cancer. Methods: Total phenolic and flavonoid contents and HPLC analysis were performed on C. oblonga leaves, P. oleracea, and A. dracunculus aerial parts extract. Anti-hypoxic activities were evaluated in asphyctic, haemic, and circulatory hypoxia models. Results: A. dracunculus extract (at 250 mg/kg) significantly improved the survival time compared to the normal saline (P0.05). In haemic hypoxia, the extracts were ineffective at any dose (P>0.05). At 250 mg/kg, P. oleracea and A. dracunculus significantly increased the survival time (P<0.001 and P0.05). Conclusion: The anti-cancer effects of C. oblonga are not dependent on the anti-hypoxic effects. P. oleracea and A. dracunculus have anti-hypoxic effects only in high doses, indicating their extracts’ weak anti-hypoxic ability or the presence of potent anti-hypoxic compounds with low concentrations in them.

The green technique is a unique way to produce functional nanoparticles. We examined the green synthesis of Ag nanoparticles (O-AgNPs) by the extract of Oxalis corniculata. Green-synthesized O-AgNPs were accomplished by monitoring critical factors such as concentration, pH, reaction time, and temperature. Several analytical techniques, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, and UV-Vis spectroscopy, were applied to characterize O-AgNPs. The SEM analysis showed O-AgNPs with a spherical shape and an average size of 33.57 nm. The XRD pattern indicated the face-centered cubic (fcc) structure of the prepared O-AgNPs. The anticancer activity of the synthesized O-AgNPs was investigated in MCF-7 (breast) and AGS (gastric) cell lines, indicating high anticancer effects against selected cell lines. The growth of all selected bacteria containing Gram+ and Gram- was inhibited by O-AgNPs. O-AgNPs showed greater inhibition in comparison to conventional antibiotics. As a result, our green synthesized AgNPs using plant extracts exhibited anticancer and antibacterial activities.

In this study, gold nanoparticles were synthesized using the fruit extract of Sambucus ebulus (S. ebulus) as a reducing, capping, and stabilizing agent. Biogenic synthesis of gold nanoparticles (Au nanoparticles) was accomplished using S. ebulus fruit extract in the presence of hydrogen tetrachloroaurate(III) trihydrate at a temperature of 65 °C and the solution stirred at 400 rpm. The characterization of the synthesized nanoparticles (SE-AuNPs) was performed using different analytical methods, such as scanning electron microscopy (FE-SEM), energy dispersion X-ray spectroscopy (EDS), Fourier transform infrared (FT-IR), X-ray diffraction analysis (XRD), and UV-vis spectroscopy. A strong absorption peak at 565 nm confirmed the formation of the gold nanoparticle. On the basis of the electron microscopy results, AuNPs were mostly spherical with an average size of 116.2 nm. The cubic crystalline structure of the prepared nanoparticles was confirmed using the XRD pattern and the average crystallite size was obtained at 28.471 nm. FT-IR analysis confirmed the presence of functional groups in the plant extract for the synthesis of nanoparticles. SE-AuNPs showed good antibacterial activity against Gram-positive and Gram-negative bacteria tested and exhibited potent antileishmanial activity. Furthermore, SE-AuNPs showed excellent antioxidant activity that inhibited DPPH radicals with an IC50 value of 21.976 µg/mL. The prepared AuNPs acted to degrade methyl orange (MO), which was performed in sodium borohydride and visible light.

Background: and Purpose: Green nanotechnology is an interesting method for the synthesis of functional nanoparticles. Because of their wide application, they have set up great attention in recent years. Objective: The present research examines the green synthesis of Ag and zero-valent iron nanoparticles (AgNPs, ZVINPs) by Feijoa sellowiana fruit extract. In this synthesis, no stabilizers or surfactants were applied. Methods: Eco-friendly synthesis of Iron and biogenic synthesis of Ag nanoparticles were accomplished by controlling critical parameters such as concentration, incubation period and temperature. Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM), Energy-Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction analysis (XRD), Dynamic Light Scattering (DLS) and UV-Vis were applied to characterize NPs. The cytotoxicity of NPs was investigated in two cell lines, MCF-7 (breast cancer) and AGS (human gastric carcinoma). A high-performance liquid chromatography (HPLC) analysis was also performed for characterization of phenolic acids in the extract. Results: Both NPs displayed powerful anticancer activities against two tumor cell lines with little effect on BEAS-2B normal cells. Synthesized AgNPs and ZVINPs inhibited the growth of all selected bacteria. Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumonia, Staphylococcus aureus, Enterococcus faecalis, Acinetobacter baumannii and Escherichia coli have been studied in two stages. We initially examined the ATCCs followed by clinical strain isolation. Based on the results from resistant strains, we showed that nanoparticles were superior to conventional antibiotics. DPPH (diphenyl-1-picrylhydrazyl) free radical scavenging assay and iron chelating activity were used for the determination of antioxidant properties. Results showed a high antioxidant activity of scavenging free radicals for ZVINPs and powerful iron-chelating activity for AgNPs. Based on the HPLC data, catechin was the major phenolic compound in the extract. Conclusion: Our synthesized nanoparticles displayed potent cytotoxic, antibacterial and antioxidant activities.