The present study describes phytoassisted synthesis of magnesium oxide nanoparticles with an aqueous extract of Swertia chirayaita. The stable magnesium oxide nanoparticles (MgONPs) formed by this method were spherical particles that were <20 nm in size. The method is cost-effective and eco-friendly. MgONPs from phytoassisted synthesis were characterized by UV-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The UV-vis absorbance spectrum of the synthesized MgONPs displayed a surface plasmon resonance at 510 nm. XRD analysis showed that the MgONPs were crystalline in nature with a face-centred cubic geometry. Further, the MgONPs tested against Gram-positive [Staphylococcus aureus-MTCC-9442, Staphylococcus epidermidis-MTCC-2639, Bacillus cereus-MTCC-9017] and Gram-negative bacteria [Escherichia coli-MTCC-9721, Proteus vulgaris-MTCC-7299, Klebsiella pneumonia-MTCC-9751] by agar-well diffusion method were found to be effective against both Gram-negative bacteria and Gram-positive bacteria.

Two Indian spices, Trachyspermum ammi and Myristica fragrans, were studied for their essential oil (EO) yielding pattern, insecticidal activity, antibacterial activity, and composition. The essential oils (EOs) of T. ammi (1.94 ± 30 mL/100 gm) and M. fragrans (5.93 ± 90 mL/100 gm) were extracted using hydrodistillation method. In Gas Chromatography analysis, the beta-pinene, alpha-pinene, alpha-p-menth-1-en-4-ol, Limonene, and elemicin were found as major constituents of T. ammi essential oil whereas M. fragrans essential oil mostly contains Gamma-Terpinolene, p-Cymene, Thymol, and beta-pinene. The insecticidal activities of EO were demonstrated using LC50 values against Plodia interpunctella and EO of T. ammi was found comparatively more effective than EO of M. fragrans. Further, individual EO and combination of essential oil were examined for antibacterial activity against three Gram (−) bacterial strains (E. coli-MTCC 443, P. vulgaris-MTCC 1771, and K. pneumoniae-MTCC number 7028) and three Gram (+) bacterial strains (S. aureus-MTCC 3381, B. subtilis-MTCC 10619, and B. megaterium-MTCC 2412) by well agar diffusion method. The essential oil in combination (CEO) exhibited higher antibacterial activity as compared with individual essential oils.

The antimicrobial effect of compound terephthalamide synthesized through aminolysis of PET waste and its complex formed through its complexation with lanthanum nitrate was investigated on different fungal species after their characterization through elemental analysis and various spectroscopic studies i.e. FTIR,UV-Visible, NMR etc. The conidia of various fungal species were exposed to both terephthalamide and its complex at variable concentration from 0.4mg/ml-1.0 mg/ml media at 37 °C. Fungal species as controls and in the presence of solvent DMSO only, were also included in the study to study the interference of solvent in antimicrobial activity of amide synthesized. Compound exposure on microbial species resulted in suppression of growths for microbes and work as good antifungal agent when complexed with La-N.