Apoptotic and Antioxidant Activity of Gold Nanoparticles Synthesized Using Marine Brown Seaweed: An In Vitro Study

Bioactive nanoparticles derived from marine brown seaweeds and their biological applications: a review

The biosynthesis of novel nanoparticles with varied morphologies, which has good implications for their biological capabilities, has attracted increasing attention in the field of nanotechnology. Bioactive compounds present in the extract of fungi, bacteria, plants and algae are responsible for nanoparticle synthesis. In comparison to other biological resources, brown seaweeds can also be useful to convert metal ions to metal nanoparticles because of the presence of richer bioactive chemicals. Carbohydrates, proteins, polysaccharides, vitamins, enzymes, pigments, and secondary metabolites in brown seaweeds act as natural reducing, capping, and stabilizing agents in the nanoparticle's synthesis. There are around 2000 species of seaweed that dominate marine resources, but only a few have been reported for nanoparticle synthesis. The presence of bioactive chemicals in the biosynthesized metal nanoparticles confers biological activity. The biosynthesized metal and non-metal nanoparticles from brown seaweeds possess different biological activities because of their different physiochemical properties. Compared with terrestrial resources, marine resources are not much explored for nanoparticle synthesis. To confirm their morphology, characterization methods are used, such as absorption spectrophotometer, X-ray diffraction, Fourier transforms infrared spectroscopy, scanning electron microscope, and transmission electron microscopy. This review attempts to include the vital role of brown seaweed in the synthesis of metal and non-metal nanoparticles, as well as the method of synthesis and biological applications such as anticancer, antibacterial, antioxidant, anti-diabetic, and other functions.

Alkaline protease functionalized hydrothermal synthesis of novel gold nanoparticles (ALPs-AuNPs): A new entry in photocatalytic and biological applications

Researchers are consistently investigating novel and distinctive methods and materials that are compatible for human life and environmental conditions This study aimed to synthesize gold nanoparticles (ALPs-AuNPs) using for the first time an alkaline protease (ALPs) derived from Phalaris minor seed extract. A series of physicochemical techniques were used to inquire the formation, size, shape and crystalline nature of ALPs-AuNPs. The nanoparticles' ability to degrade methylene blue (MB) through photocatalysis under visible light irradiation was assessed. The findings demonstrated that ALPs-AuNPs exhibited remarkable efficacy by destroying 100 % of MB within a mere 30-minute irradiation period. In addition, the ALPs-AuNPs demonstrated remarkable effectiveness in inhibiting the growth of gram-positive (S. aureus) and gram-negative (E. coli) bacteria. The inhibition zones examined against the two bacterial strains were 23(±0.3) mm and 19(±0.4); 13(±0.3) mm and 11(±0.5) mm under light and dark conditions respectively. The ALPs-AuNPs exhibited significant antioxidant activity by effectively scavenging 88 % of stable and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. As a result, the findings demonstrated that the environmentally friendly ALPs-AuNPs showed a strong potential for MB degradation and bacterial pathogen treatment.

Retracted: Apoptotic and Antioxidant Activity of Gold Nanoparticles Synthesized Using Marine Brown Seaweed: An In Vitro Study

[This retracts the article DOI: 10.1155/2022/5746761.].

Enhancing Anti-cancer Activity: Green Synthesis and Cytotoxicity Evaluation of Turmeric-Gold Nanocapsules on A549 Lung Cancer Cells

Background Lung cancer remains a major global health concern, with a notable increase in new cases in recent years. This study aims to investigate the cytotoxic effects of polymeric turmeric-gold nanocapsules on A549 human lung cancer cells, utilizing green-synthesized gold nanoparticles from Curcuma longa L. and ethyl cellulose-based nanocapsules. Methods Gold nanoparticles were synthesized using the aqueous root extract of Curcuma longa L., and the resulting nanoparticles were characterized using UV-Vis, fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and energy dispersive x-ray (EDX) techniques. Subsequently, polymeric nanocapsules of turmeric with encapsulated gold nanoparticles were prepared. The cytotoxicity of these nanocapsules was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay on both A549 lung cancer cell lines and normal cell lines. Results The turmeric-gold nanocapsules exhibited a half maximal inhibitory concentration (IC50) value of 40 μg/ml, while the gold nanoparticles alone showed an IC50 value of 60 μg/ml when tested on A549 cells. Furthermore, apoptosis was observed in A549 cells treated with turmeric-gold nanocapsules. The combination of gold nanoparticles and turmeric polymer (gold turmeric nanocapsules) demonstrated a more potent anti-cancer effect on the lung cancer cell line, with an IC50 value of 40 μg/ml compared to green-synthesized gold nanoparticles (IC50 of 60 μg/ml). Conclusion The utilization of polymeric nanocapsules of turmeric, with green-synthesized gold nanoparticles, presents a promising solution to overcome the limited water solubility of turmeric. The results suggest that the combination of gold nanoparticles and turmeric enhances the cytotoxic effects on A549 human lung cancer cells. These findings contribute to the potential application of turmeric-gold nanocapsules as a novel therapeutic approach in lung cancer research.