Development of Uniform Porous Carbons From Polycarbazole Phthalonitriles as Durable CO2 Adsorbent and Supercapacitor Electrodes.

Advances in new porous materials have recognized great consideration in CO2 capture and electrochemical energy storage (EES) applications. In this study, we reported a synthesis of two nitrogen-enriched KOH-activated porous carbons prepared from polycarbazole phthalonitrile networks through direct pyrolysis protocol. The highest specific surface area of the carbon material prepared by pyrolysis of p-4CzPN polymer reaches 1,279 m2 g-1. Due to the highly rigid and reticular structure of the precursor, the obtained c-4CzPN-KOH carbon material exhibits high surface area, uniform porosity, and shows excellent CO2 capture performance of 19.5 wt% at 0°C. Moreover, the attained porous carbon c-4CzPN-KOH showed high energy storage capacities of up to 451 F g-1 in aqueous electrolytes containing 6.0 M KOH at a current density of 1 A g-1. The prepared carbon material also exhibits excellent charge/discharge cycle stability and retains 95.9% capacity after 2000 cycles, indicating promising electrode materials for supercapacitors.

Carbazole-tagged pyridinic microporous network polymer for CO2 storage and organic dye removal from aqueous solution.

A microporous organic polymer (Cz-pyr-P) was prepared from a monomer of pyridine-imides, flanked by four carbazoles, and its application as an adsorbent for both CO2 and methylene blue dye in wastewater was investigated. The polymer was synthesised by oxidative polymerisation facilitated by FeCl3 and comprehensively characterised using routine spectroscopic, thermal, textural, and morphological analyses. With a high surface area of 1065 m2/g and a median pore width of 8.06 Å, the nitrogen-enriched Cz-pyr-P reversibly adsorbed 19.41 wt% (273 K) and 12.78 wt% (295 K) CO2 at 1 bar, with a good isosteric heat value of CO2 adsorption (28.5 kJ/mol). For the removal of methylene blue dye from wastewater, Cz-pyr-P exhibited excellent partition coefficient of 380.10 mg/g µM with an equilibrium time of 6 min which is shorter than previously reported values for other materials. The results indicate that Cz-pyr-P with desirable functionality could be utilised for reaching CO2 emission reduction targets as well as for wastewater treatment.

Plant phenyl-propanoids-conjugated silver nanoparticles from edible plant Suaeda maritima (L.) dumort. Inhibit proliferation of K562-human myeloid leukemia cells.

The present study portrays the isolation of four phenylpropanoids - ferulic acid (FA), sinapic acid (SA), caffeic acid (CA), and chlorogenic acid (CHA) from the water extract of Suaeda maritima (L.) Dumort, a phytochemically less explored Indian medicinal plant. Further, synthesis and characterization of silver and gold nanoparticles using the isolated phenylpropanoids were done. The silver nanoparticles synthesized from S. maritima water extract along with silver nano-conjugated forms of the isolated compounds exhibited appreciable anti-leukemic activity against K562 cells (human myeloid leukemia). Especially, the ferulic and CA-conjugated silver nanoparticles showed significant (P < .01) activity against leukemia.

Antimicrobial flavonoids isolated from Indian medicinal plant Scutellaria oblonga inhibit biofilms formed by common food pathogens.

Scutellaria oblonga Benth., a hitherto phytochemically unexplored Indian medicinal folklore plant was extracted with acetone and subjected to chromatography to yield nine flavonoids, for the first time from this plant. Antimicrobial assays were performed against 11 foodborne pathogens, and three molecules (Techtochrysin, Negletein and Quercitin-3-glucoside) depicted significant activity. These molecules were assessed for their rate of antibacterial action using time-kill curves which depicted complete inhibition of most of the bacteria within 12-16 h. The significant biofilm-reducing capability exhibited by these three molecules formed a significant finding of the current study. In most of the experiments, a 90-95% reduction in biofilms was observed. Thus, flavonoids as natural molecules from S. oblonga could be further researched to be used as potent antimicrobial and antibiofilm agents.

Scientific validation of the different purification steps involved in the preparation of an Indian Ayurvedic medicine, Lauha bhasma.

ETHNOPHARMACOLOGICAL RELEVANCE: Lauha bhasma (iron ash) is one of the iron-based herbo-metallic preparations used in Ayurvedic medicine for treating various ailments due to iron deficiency. MATERIALS AND METHODS: The preparation of Lauha bhasma (iron ash) requires normal purification (heat treatment in vegetable and animal products), special purification (treatment with herbal constituents) and calcination steps aimed at converting the raw material to a suitable therapeutic form. In this study, we have systematically and scientifically evaluated through a series of qualitative tests and modern analytical tools the importance of the treating media. RESULTS: Our data demonstrates that these steps are necessary to remove the grease and scales in the raw material. While heating, microcracks appeared on the surface of the iron, which improved the reactivity with the herbal constituents in addition to incorporating nanostructured features. Further, the use of plant products facilitated the removal of Fe³âº present in the raw material by forming soluble complexes. The Fe²âº present in the raw materials also forms an insoluble complex with the herbal constituents in the presence of UV radiation. CONCLUSIONS: In conclusion, our data summarily suggest that the purification steps involved in the preparation of Lauha bhasma (iron ash) are critical.