Eco-friendly Green Synthesis of Silver Nanoparticles from Leaf Extract of Solanum khasianum: Optical Properties and Biological Applications.

The green synthesis of silver nanoparticles (AgNPs) was considered to be efficacious over other approaches due to their eco-friendliness, cost-effectiveness, and high stability. The biosynthesis of AgNPs was achieved by the reduction of silver nitrate using the aqueous leaf extract of Solanum khasianum. The biosynthesized AgNPs were examined by a color change and UV-Vis spectroscopy with an absorption spectrum at 440 nm. The biomolecules existing in S. khasianum leaf extract accountable for bioreduction and capping of AgNPs were analyzed by FTIR analysis and confirmed the presence of alcohols, phenols, alkanes, carboxylic acid, nitro compounds, and amines. The crystalline nature of Sk-AgNPs with face-centered cubic lattice was confirmed by X-ray diffraction (XRD) spectrum. The average crystallite size of Sk-AgNPs was computed as 15.96 nm. The lattice constant, unit cell volume, and spacing values of Sk-AgNPs were parallel to the values indexed in the Joint Committee on Powder Diffraction Standard of silver (JCPDS-04-0783). Scanning electron microscope (SEM) imaging witnessed the spherical structure of synthesized AgNPs. Energy dispersive X-ray (EDX) spectrum acknowledged the AgNPs fabrication with strong signals of silver atoms at 3 keV energy. The biofabricated Sk-AgNPs showed a photoluminescence (PL) emission spectrum of 445 nm with an excitation at 330 nm. Sk-AgNPs showed considerable DPPH radical scavenging activity (87.98%) than BHT (86.14%) and also exhibited significant antidiabetic activity compared to acarbose. Sk-AgNPs revealed antibacterial potentiality against B. sphaericus, E. coli, S. aureus, and P. fluorescens. Moreover, Sk-AgNPs showed dose-dependent cytotoxicity against MCF-7 cell line. This method of green synthesis would support the eco-friendly fabrication of AgNPs from S. khasianum leaf extract with considerable therapeutic activities.

Green synthesis, characterization, photoluminescence and biological studies of silver nanoparticles from the leaf extract of Muntingia calabura.

The current protocol describes the green synthesis of silver nanoparticles, which shown photoluminescence, antioxidant, anti-inflammatory, antidiabetic and antibacterial effects utilizing leaf extracts of Muntingia calabura. High-throughput methods (UV-Vis, FTIR, XRD, SEM, EDX and PL) were used to characterize the synthesized Mc-AgNP's. The surface plasmon resonance of Mc-AgNP's was detected around 456 nm using UV-Vis spectroscopy. The different functional groups were revealed from the FTIR spectra. The average crystallite size of Mc-AgNP's was found to be 15.52 nm. The morphology of Mc-AgNP's was found as spherical using SEM. Photoluminescence spectrum showed emission around 445 nm with an excitation of 330 nm.

GC-MS profiling and antibacterial activity of Solanum khasianum leaf and root extracts.

Background: Solanum khasianum is an important medicinal herb of the Solanaceae family. The present study was focused to determine the bioactive compounds in S. khasianum leaf and root extract by GC-MS analysis and their antibacterial activity by agar well diffusion method. Results: Sixteen bioactive compounds were detected in leaf extract and thirty-two compounds in root methanolic extract by GC-MS. The major potent compounds identified in leaf and root extracts were heptadecane 9-hexyl (43.65%) and stigmasterol (23.18%). The root extract showed increased antibacterial activity than leaf extract. Conclusion: These extracts possessed significant antibacterial activity against the tested bacterial isolates in dose-dependent manner. This study provides the phytoconstituents, antibacterial property and scientific evidence for the traditional claim and use of S. khasianum.

Sweetpotato cultivars responses to interactive effects of warming, drought, and elevated carbon dioxide.

Plants are sensitive to changes projected in climates, such as elevated carbon dioxide (eCO2), high temperature (T), and drought stress (DS), which affect crop growth, development, and yield. These stresses, either alone or in combination, affect all aspects of sweetpotato plant growth and development, including storage root development and yield. We tested three sweetpotato cultivars (Beauregard, Hatteras, and LA1188) responses to eight treatments (Control, DS, T, eCO2, DS + T, T + eCO2, DS + eCO2, DS + T + eCO2). All treatments were imposed 36 days after transplanting (DAP) and continued for 47 days. Treatments substantially affected gas exchange, photosynthetic pigments, growth, and storage root components. Cultivars differed considerably for many of the measured parameters. The most significant negative impact of DS was recorded for the shoot and root weights. The combination of DS + T had a significant negative effect on storage root parameters. eCO2 alleviated some of the damaging effects of DS and high T in sweetpotato. For instance, eCO2 alone or combined with DS increased the storage root weights by 22% or 42% across all three cultivars, respectively. Based on the stress response index, cultivar "Hatteras" was most tolerant to individual and interactive stresses, and "LA 1188" was sensitive. Our findings suggest that eCO2 negates the negative impact of T or DS on the growth and yield of sweetpotato. We identified a set of individual and interactive stress-tolerant traits that can help select stress cultivars or breed new lines for future environments.