No abstract

Biodegradable magnesium (Mg) alloys have potential applications in orthopedic implants due to their mechanical and osseointegration properties. However, the surface characteristics, biocompatibility, and toxicity of the released corrosion products in the form of magnesium oxide (MgO) and magnesium hydroxide (Mg(OH)2) nanoparticles (NPs) at the junction of implants and in the surrounding tissue are not completely understood. Here, we investigated in vitro cytotoxicity and morphological changes in human fetal osteoblast (hFOB) 1.19 cells in response to various concentrations (1 mM, 5 mM, 10 mM, and 50 mM) of MgO/Mg(OH)2 NPs by live/dead assay and scanning electron microscopy (SEM). In this study, we performed a surface characterization of MgO/Mg(OH)2 NPs to evaluate the size of the NPs. Further, an immersion test was performed in Dulbecco’s Modified Eagle’s Medium (DMEM) with randomly selected various concentrations (1 mM, 5 mM, 10 mM, 50 mM, and 100 mM) of MgO/Mg(OH)2 NPs to understand the degradation behavior of the NPs, and the change in the pH values from days 1 to 7 was measured. After conducting an immersion test for seven days, the highest concentration (100 mM) of MgO/Mg(OH)2 NPs was selected to study the element depositions on nanoparticles through scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDX) mapping. The results from this in vitro cytotoxicity study suggest that less than or equal to 5-mM concentrations of MgO/Mg(OH)2 NPs are tolerable concentrations for hFOB 1.19 cells. This study provides a foundational knowledge of MgO/Mg(OH)2 NP cytotoxicity in hFOB 1.19 cells that can help to develop future sustainable biodegradable magnesium-based alloys for orthopedic applications.

Rotula aquatica Lour is a small branched shrub that grows characteristically among rocks and trailing over gravel in stream beds. It belongs to the family Boraginaceae and widely distributed throughout India. It is commonly called as Pasanabheda. The present study was aimed to evaluate the total phenolics and in vitro antioxidant activity in root and leaf extracts of Rotula aquatica Lour. The dried roots and leaves were subjected to soxhlet extraction utilizing chloroform and methanol followed by preliminary qualitative phytochemical analysis. Total phenolic content was estimated by Folin-Ciocalteu method and in vitro antioxidant assays were performed using various radical scavenging activities viz. DPPH, superoxide anion, nitric oxide, hydroxyl and iron chelating activities at different concentrations. The results of the total phenolic content estimation was expressed in terms of equivalence with standard and the antioxidant potentiality of various scavenging and chelating activity were expressed in terms of IC50 values. The results showed that both root and leaves possess significant antioxidant activity even though the former was found to be superior than the latter in terms of parameters assessed. Further the methanol extracts were proved to be an ideal for the materials subjected to investigation.

Magnesium (Mg)-based alloys have the potential for bone repair due to their properties of biodegradation, biocompatibility, and structural stability, which can eliminate the requirement for a second surgery for the removal of the implant. Nevertheless, uncontrolled degradation rate and possible cytotoxicity of the corrosion products at the implant sites are known current challenges for clinical applications. In this study, we assessed in vitro cytotoxicity of different concentrations (0 to 50 mM) of possible corrosion products in the form of magnesium oxide (MgO) and magnesium hydroxide (Mg(OH)2) nanoparticles (NPs) in human fetal osteoblast (hFOB) 1.19 cells. We measured cell proliferation, adhesion, migration, and cytotoxicity using a real-time, label-free, non-invasive electric cell-substrate impedance sensing (ECIS) system. Our results suggest that 1 mM concentrations of MgO/Mg(OH)2 NPs are tolerable in hFOB 1.19 cells. Based on our findings, we propose the development of innovative biodegradable Mg-based alloys for further in vivo animal testing and clinical trials in orthopedics.

Objective:Orchids are widely used the economically important ornamental plant. Conventionally, they were also used for the treatment of several diseases. In the present study, five species of medicinal Orchids from South India were selected to evaluate their antioxidant potential. Methods:The selected species were extracted by Soxhlet method using 70% ethanol. The extracts obtained were analyzed for various quantitative and antioxidant assays followed by correlation analysis in between quantitative and antioxidant activity.Results: Antioxidant data revealed that among the extracts of five orchids, Coelogyne breviscapa was proved to be superior in terms of antioxidant activities, followed by Aerides maculosum, Dendrobium macrostachyum, Pholidota pallida, and Vanda testacea. Correlation analysis was performed, and the results proved simple positive correlation and highest average value of "r" (correlation coefficient) for antioxidant activities with quantitative were the total antioxidants, total phenolics, total flavonoids, and ascorbic acid content. Among the qualitative antioxidant activities, the highest average value of "r" was shown by 2, 2-diphenyl-1-picrylhydrazyl, iron chelating, 2,2-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid, and superoxide radical. Conclusion:The study documents that orchid plants have significant antioxidant potential which can contribute to human health.