The fabrication of metal nanoparticles through green synthetic pathways using plant extracts has increased attention due to low cost, benevolent methods, fewer hazardous byproducts, and applications. Silver nanoparticles (AgNPs) were synthesized by reacting to aqueous root extracts of Rubus ellipticus Sm. (RERE) with AgNO₃ solution (1 mM) at an ambient condition. The visual change of color from light yellow to reddish brown and the absorption peak at 416‐420 nm in the UV‐visible spectra indicated the formation of AgNPs in the solution. The shifting of the positions in the FTIR spectra indicated the potential role of the functional groups as capping and stabilizing agents. The powder XRD diffractogram exposed the crystalline nature of the nanoparticles. The surface morphology and the elemental composition of the AgNPs were established by the FESEM and EDX analysis. The TEM images revealed the spherical and monodispersed nanoparticles of size ranging from 13.85 to 34.30 nm with an average of 25.20 ± 7.01 nm (n = 10). The biogenic AgNPs showed a better 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity with lower IC₅₀ (13.83 ± 0.33 μg/mL) as compared to that of the RERE with IC₅₀ (15.86 ± 4.14 μg/mL). The synthesized AgNPs showed higher zones of inhibition (ZOI) on the agar well diffusion method against Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), and Klebsiella pneumoniae (ATCC 700603). The result of this study highlights the potential benefits of R. ellipticus root extract‐based AgNPs for biomedical practices.

Plants have long been considered as a basis of medicines for different indigenous cultures around the globe. They continue as a prominent source of important phytoconstituents which exhibit significant biological activities. In this study, we performed the phytochemical screening, estimation of total phenolic and flavonoids, antioxidants, and antimicrobial activities of the stem bark of Beilschmiedia roxburghiana Nees using different solvents. The total phenolic and total flavonoid contents ranged from 106.73±1.62mg GAE/g and 99.32±0.66mg QE/g (methanol extract) to 65.59±1.79mg GAE/g and 29.98±0.90mg QE/g (n-hexane extract), respectively. The maximum 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity with a half-maximal inhibitory concentration (IC₅₀) of 39.86±3.69μg/mL was observed for methanol extract followed by aqueous (IC₅₀=43.55±6.16μg/mL), ethyl acetate (IC₅₀=44.30±5.88μg/mL), dichloromethane (IC₅₀=71.50±4.70μg/mL), and the lowest activity was observed for n-hexane extract. The disc diffusion method revealed that the ethyl acetate extract exhibited relatively higher activity against Salmonella typhi (ZOI=13mm), and moderate activities against Shigella sonnei, Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus aureus (ZOI=12mm). The methanol and aqueous extracts showed nearly parallel and the n-hexane and dichloromethane extracts exhibited mild antibacterial activities. The results indicated that the polarity index of the extracting solvents amplified the biological activities of the extract. The study is helpful to support the validity of the traditional application of the plant as natural medicine.

Bauhinia variegata is well-known medicinal plant used from the ancient era to till date for their medicinal values. The methanolic extract of Bauhinia variegata barks was screened for phytochemical constituents, antioxidant, phytotoxic and microbial activity. The microbial activity was tested against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi at different concentration of 10, 15 and 20 mg/mL by agar well diffusion method. The plant extract showed the potent antimicrobial activity against the Staphylococcus aureus, Salmonella typhi, Bacillus subtilic and Escherichia coli with zone of inhibition 14 mm, 12mm, 14mm and 11mm respectively. Phytochemical analysis of the extract revealed that the antioxidant and antimicrobial activity of the plant materials is due to the presence of active secondary metabolites. In DPPH free radical scavenging assay the IC50 value of Bauhinia variegata was found to be 6.48±0.08 ?g/mL, while the IC50 value of the reference standard ascorbic acid was 45.93?g/mL. The extract of Bauhinia variegata, contains high value of phenolic (156.30±0.3 mg GAE/gm) and flavonoid (16.04±1.4 mg QE/gm) content exhibited the high antioxidant activity. The in-vitro phytotoxic bioassay showed 65%, 40%, and 25% growth regulation at just higher conc. of 1000, 100 and 10 ?g/mL with number of fronds 07, 12 and 15 respectively with respect to standard drug Paraquat of concentration 0.015?g/mL.Journal of Institute of Science and Technology, 2015, 20(2): 37-41

The investigation of using medicinal plants for the production and application of silver nanoparticles (AgNPs) has attracted growing research interest. In this study, AgNPs are synthesized from the stem barks of the Pyrus pashia medicinal plant using a biosynthetic strategy. The reaction conditions were optimized under ambient conditions, including concentration, temperature, time, and pH, and various techniques were employed, such as UV-visible, FTIR, XRD, FESEM, and TEM, to characterize the synthesized AgNPs. The AgNPs produced through this biosynthesis method were found to be spherical and polydispersed, with an average size of 23.92 ± 7.04 nm. The synthesized AgNPs demonstrated an enhanced DPPH free radical scavenging capacity compared to the aqueous extract, with IC₅₀ values of 10.67 ± 0.05 µg/mL and 13.66 ± 0.35 µg/mL, respectively. In the agar well diffusion method, the synthesized AgNPs showed higher antibacterial activity than that of the extract against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Salmonella typhi (ATCC 14028), and Shigella sonnei (ATCC 25931). Based on these findings, the study suggests that green synthesized AgNPs from P. pashia could be used for biomedical applications.

Methanol and hexane extracts of leaves of Moringa oleifera and aerial parts of Alternanthera sessilis were screened for the presence of different classes of phytoconstituents. Phytochemical screening revealed the presence of alkaloids, flavonoids, carbohydrates, terpenoids, polyphenols, glycosides, and coumarins in methanol extracts. Volatile oils, quinines, and phytosterols were absent in all extracts and saponins were present in all extracts. The biological activity of all the extracts was tested by performing brine shrimp bioassay. All the extracts except hexane extract of Moringa oleifera were found to be cytotoxic against brine shrimp nauplii. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay was used to evaluate the antioxidant activity of the extracts. Methanol extracts of Moringa oleifera showed the strongest antioxidant activity with an IC50 value of 65.77 μg/mL. Regarding the ascorbic acid (IC50 value 39.53 μg/mL) as standard, methanol extracts of both plants showed high free radical scavenging activity than that of hexane extracts.

Acetylcholinesterase (AChE) inhibitors and calcium channel blockers are considered effective therapies for Alzheimer’s disease. AChE plays an essential role in the nervous system by catalyzing the hydrolysis of the neurotransmitter acetylcholine. In this study, the inhibition of the enzyme AChE by Sarcorucinine-D, a pregnane type steroidal alkaloid, was investigated with experimental enzyme kinetics and molecular dynamics (MD) simulation techniques. Kinetics studies showed that Sarcorucinine-D inhibits two cholinesterases—AChE and butyrylcholinesterase (BChE)—noncompetitively, with K_i values of 103.3 and 4.66 µM, respectively. In silico ligand-protein docking and MD simulation studies conducted on AChE predicted that Sarcorucinine-D interacted via hydrophobic interactions and hydrogen bonds with the residues of the active-site gorge of AChE. Sarcorucinine-D was able to relax contractility concentration-dependently in the intestinal smooth muscles of jejunum obtained from rabbits. Not only was the spontaneous spasmogenicity inhibited, but it also suppressed K⁺-mediated spasmogenicity, indicating an effect via the inhibition of voltage-dependent Ca²⁺ channels. Sarcorucinine-D could be considered a potential lead molecule based on its properties as a noncompetitive AChE inhibitor and a Ca²⁺ channel blocker.