Green synthesis of Zirconium nanoparticles using Punica granatum (pomegranate) peel extract and their antimicrobial and antioxidant potency

The biosynthesis of metal oxide nanoparticles provides an excellent alternative to the chemical synthesis approach. The aim of the current study was a green and eco-friendly synthesis of zirconium nanoparticles (ZrNPs) from fruit peels of Punica granatum (Pomegranate). The synthesis of ZrNPs was confirmed using a UV-visible spectrophotometer. The functional groups present on surface of ZrNPs were analyzed using FTIR. The average size of obtained ZrNPs was analyzed using SEM and DLS and it was around 20-60 nm. The antimicrobial activity of obtained ZrNPs was tested against Gram-positive strains (Bacillus subtilis and Staphylococcus aureus), Gram-negative strains (Escherichia coli and Klebsiella pneumoniae) and Fungi (Aspergillus niger) by agar well diffusion method. ZrNPs showed maximum zone of inhibition against S. aureus (19 mm) and A. niger (18 mm) at the maximum concentration of 200 μg/mL. The antioxidant scavenging activity of obtained ZrNPs was analyzed using the following methods: DPPH radical scavenging activity, Hydroxyl radical scavenging activity, Ferric reducing antioxidant power and hydrogen peroxide radical scavenging activity. This the first and foremost study on ZrNPs synthesized using P. granatum fruit peel extract reporting their efficacy as antimicrobial agents against Bacteria and Fungi. Considering the tolerance of zirconium towards human body, it can also be used as antimicrobial coating material on human implants.

Fungi fabrication, characterization, and anticancer activity of silver nanoparticles using metals resistant Aspergillus niger

The purpose of this study was to assess the bio-fabrication possibilities of pre-isolated (from bauxite mine tailings) metal-tolerant Aspergillus niger biomass filtrate and the anticancer potential of synthesized silver nanoparticles (AgNPs) tested with a Human Cervical cancer cell line (HeLa cells: Henrietta Lacks cells). The nitrate reduction test demonstrated that A. niger has the ability to reduce nitrate, and filtrate derived from A. niger biomass efficiently fabricated AgNPs from AgNO₃, as demonstrated by a visible color change from pale greenish to brownish. The UV-visible spectroscopy analysis revealed an absorbance peak at 435 nm, which corresponded to the AgNPs. These AgNPs have been capped and stabilized with several functional groups related to various bioactive molecules such as aldehyde, benzene rings, aldehydic, amines, alcohols, and carbonyl stretch protein molecules. Fourier-Transform Infrared Spectroscopy (FTIR) analysis confirmed the capping and stabilizing chemical bonding pattern. Scanning Electron Microscopy (SEM) revealed that the synthesized AgNPs were spherical, with an average size of 21.38 nm. This bio-fabricated AgNPs has in-vitro anticancer potential when tested against the HeLa cell line due to its potential size and shape. At 100 g mL^-1 concentrations of this bio-fabricated AgNPs, the anticancer activity percentage was found to be 70.2%, and the IC₅₀ value was found to be 66.32 g m^-1. These findings demonstrated that the metal-tolerant A. niger cell filtrate could produce AgNPs with anticancer potential.

Role of Nanoparticles in Environmental Remediation: An Insight into Heavy Metal Pollution from Dentistry

Environmental damage is without a doubt one of the most serious issues confronting society today. As dental professionals, we must recognize that some of the procedures and techniques we have been using may pose environmental risks. The usage and discharge of heavy metals from dental set-ups pollute the environment and pose a serious threat to the ecosystem. Due to the exclusive properties of nanosized particles, nanotechnology is a booming field that is being extensively studied for the remediation of pollutants. Given that the nanoparticles have a high surface area to volume ratio and significantly greater reactivity, they have been greatly considered for environmental remediation. This review aims at identifying the heavy metal sources and their environmental impact in dentistry and provides insights into the usage of nanoparticles in environmental remediation. Although the literature on various functions of inorganic nanoparticles in environmental remediation was reviewed, the research is still confined to laboratory set-ups and there is a need for more studies on the usage of nanoparticles in environmental remediation.

β-Sitosterol attenuates carbon tetrachloride-induced oxidative stress and chronic liver injury in rats

Chronic liver diseases are clinically silent and responsible for significant morbidity and mortality worldwide. β-Sitosterol (BSS), major phytosterol in plants, has a wide spectrum of protective effect against various chronic ailments. We investigated the hepatoprotective effect of BSS against carbon tetrachloride (CCl₄)-induced chronic liver injury in rats. Thirty rats were divided into five groups, with six animals in each group. Group I rats served as control while groups II, III, IV, and V rats were injected intraperitoneally with CCl₄ (0.2 mL/100 g b.w. in olive oil (1:1)) for 7 consecutive weeks. After 7 weeks, group II rats were left without any treatments and served as CCl₄ alone group, while groups III, IV, and V rats were treated with BSS 25 and 50 mg/kg b.w. and silymarin 100 mg/kg b.w. as oral post-treatments respectively, for the next 4 weeks. At the end of the experiment, hepatotoxicity marker enzymes in serum, oxidative stress, and fibrosis marker were analyzed. CCl₄ administration caused significant elevation of marker enzymes of hepatotoxicity in serum and increased lipid peroxidation and fibrosis markers such as hydroxyproline, collagen, α-smooth muscle actin, vimentin, desmin, and matrix metalloproteinases 9 in liver tissue of rats. This treatment also caused a significant diminution of intracellular enyzmic antioxidants such as SOD and CAT in the liver tissue of rats. All the above adversities were significantly mitigated by the BSS post-treatments. The results suggest that BSS could have a hepatoprotective effect against oxidative stress-mediated CLD induced by CCl₄.