The green methodologies of nanoparticles with plant extracts have received an increase of interest. Silver nanoparticles (Ag NPs) have been utilized in a many of applications in the last few decades. The current study presents the synthesis of Ag NPs with aqueous extract of Brassica oleracea sub sp. botrytis (L.) as a stabilizing agent. UV-visible spectroscopy, FTIR, XRD, SEM, TEM, and EDAX analysis were performed to study the synthesized Ag NPs. The synthesized Ag NPs have been measured with dynamic light scattering (DLS), the average size and charge were discovered to be 81.62 ± 1.14 nm and -11.3 ± 2.51 mV, respectively. Furthermore, as-formed AgNPs shown strong antibacterial activity against the Gram-positive bacteria (Staphylococcus aureus). According to the results of this investigation, green synthesized Ag NPs with Brassica oleracea sub sp. botrytis (L.) may be used in biomedicine as a replacement agent for biological applications.

The emergence of antimicrobial resistance has led to an urgent need for novel antimicrobial drugs. This study aimed to determine the antioxidant and antimicrobial potentials in silico and in vitro of Pandanus amaryllifolius Roxb. ethanolic extract. The extracts were subjected to gas chromatography-mass spectrometry (GC-MS) analysis to identify the compounds. In silico antimicrobial studies were performed to gain insights into the possible mechanism of action of the active compounds as antimicrobials. The antimicrobial activities of the ethanolic extracts were assessed using the agar well diffusion method against the Surabaya strain of Escherichia coli and Staphylococcus aureus. Antioxidant properties of the extract were done using DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and ABTS [2,2’-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid)] inhibition assays. The phytochemical screening revealed that the extract has high flavonoids and polyphenols contents. The GC-MS analysis detected the presence of 52 bioactive substances, with n-hexadecanoic acid, 9, 12, 15-octadecatrienoic acid, benzofuran 2,3-dihydro-. quinic acid, neophytadiene as major compound. Molecular docking studies showed that these compounds have a high binding affinity towards the target proteins, thereby inhibiting their activities. The ethanolic extract of P. amaryllifolius Roxb. exhibited antioxidant and antimicrobial activities. The IC₅₀ were 11.96 ± 4.01 μg/ml and 26.18 ± 7.44 μg/ml for DPPH and ABTS. The diameters of inhibition zones (DIZ) and percentage of inhibition (PI) were calculated and varied for every single pathogen 16.44 ± 1.21mm/66.76 ± 4.92% (50%) and 21.22 ± 0.11mm/82.49 ± 3.91% (50%) for E. coli and S. aureus (DIZ/PI) respectively. Overall, this study provides information on the mechanism responsible for P. amaryllifolius Roxb. extract as a natural antimicrobe and lays the foundation for further studies to isolate and characterize the active compounds as antimicrobial candidates.

Rechargeable batteries, which are used for renewable energy storage, have paved the way for reducing the enormous pressure of the energy crisis and environmental pollution. Over the last five years, MXenes and MBenes have gained more and more attentions in the fields of nanomaterials, physics and chemistry. MXenes and MBenes (two-dimensional transition metal carbide/carbonitride family and metal boride family) have attracted growing focus in the energy storage field because of their large specific surface area, excellent conductivity, tunable interlayer spaces, compositional diversity, and superior chemical durability in batteries. Furthermore, the performance management strategies, next-stage research prospects, and remaining practical challenges for MXene-based materials in battery applications are discussed in detail. This chapter may provide some guidance for the development and application of MXene and MBene-based electrode materials in renewable electrochemical energy storage.

This study investigates the rare seaweed alga Dictyota bartayresiana lamour for biological activity. Antioxidant and antibacterial activities were examined. An MTT assay was carried out to examine cytotoxicity activity against colon cancer cells. The HPTLC analysis was performed for four different extracts, which exhibited clear flavonoid band formation at 254 nm and 366 nm with varied ranges of R_f values: methanolic extract (R_f 0.87), acetone extract (R_f 0.82), and benzene (R_f 0.83). Methanolic Extract Fraction One (MEF1) has a distinct band formation at 366 nm, it is shown to have the highest inhibition (6.20 ± 0.53 mm) against Escherichia coli, and the MTT assay reveals that the aqueous extract of Dictyota bartayresiana extract has an IC₅₀ value of 300 µg/mL. It is divulged that methanolic extract shows the highest phytochemical compound level among the four extracts of Dictyota bartayresiana. A GC/MS analysis was employed to investigate the flavonoid profile of the crude seaweed extract. Although LC/MS is typically preferred for flavonoid analysis due to thermal sensitivity, GC/MS was used in this study owing to time constraints, with optimized conditions to reduce thermal degradation. The GC-MS analysis identified Quinoline and other flavonoids, suggesting potential bioactivity. The cytotoxicity activity of MEF1 shows that the development of a promising drug may be evaluated from a seaweed source. The present study provides excellent insight with the first report of the biologically active compound of Dictyota bartayresiana.

The demand for antiviral products is more to avoid the spread of infections and enhance product quality. Antiviral is an emerging technology where nanotechnology has a vital role in the growth arrest of the microorganism. Nanomaterials are proved to be clean, low cost, eco-friendly, and have a wide range of applications in several fields of environmental, agricultural, biomedical, defense, etc. These nanomaterials have distinctive physical and chemical properties because of the larger surface area to volume ratio. Many metals and metal-oxide-based nanomaterials have antimicrobial and antiviral properties because they disturb the respiratory enzymes leading to DNA damage of the microorganism. This chapter aims to gather information related to the current technologies of nanomaterials and their applications of emerging antiviral technologies in biomedical fields.