In silico molecular docking of cyclooxygenase (COX-2), ADME-toxicity and in vitro evaluation of antioxidant and anti-inflammatory activities of marine macro algae.

The marine ecosystem harbors unique and diverse bioactive compounds that can offer a vast repertoire of molecules with therapeutic properties. In the present study, four different species of red marine seaweeds were analyzed for its phytoconstituents and the potent antioxidant and anti-inflammatory activity of the methanolic extracts were screened and determined. The results revealed that, among the 4 samples, G. corticata, scored a good antioxidant potential by DPPH (67.61 ± 1.23%, IC50 = 577.7 µg) and metal chelation assay (29.40 ± 0.32%, IC50 = 1684 µg). The anti-inflammatory analysis has shown that, H. dialata was found to exhibit maximum inhibition against the albumin denaturation (83.50 ± 0.24%), whereas G. corticata was observed to measure a maximum inhibition in heat-induced hemolysis (60.40 ± 0.46%) and proteinase inhibition assay (83.30 ± 0.18%). An extensive literature survey was carried out for the bioactive compounds in G.corticata; it was examined for drug likeliness by ADME analysis and toxicological parameters. Further, the best selected bioactive compounds were subjected to in silico molecular docking with pro-inflammatory target, cyclooxygenase (COX-2). Hexadecanal and Neophytadiene were reported to obtain the highest binding affinity (-5.3) for COX-2 enzyme. Hence, in silico molecular docking studies had shown that G. corticata was found to possess potential anti-inflammatory activity that can prevent conversion of arachidonic acid to prostaglandins by inhibiting COX-2. In addition, molecular dynamic simulation studies have shown the stability of Hexadecanal-6 COX complex. To conclude, the outcomes of the present study may shed light on the understanding of the usage of bioactive compounds for therapeutic purpose.

Alkyl amine and vegetable oil mixture-a viable candidate for CO2 capture and utilization.

In this present work, the absorption of CO2 in alkyl amines and vegetable oil mixture has been evaluated. The results showed that the absorption is higher in alkyl amines and vegetable oil mixture compared with the aqueous alkyl amines. In addition to that, by employing the greener and non-toxic vegetable oil media, the CO2 gas has been captured as well as converted into value-added products, such as carbamates of ethylenediamine, diethylenetriamine, and triethylenetetramine. The carbamates have been isolated and characterized by Fourier transform infrared and 1H and 13C nuclear magnetic resonance spectroscopic techniques. The formation of these products in precipitate form has not been observed in the case of aqueous medium. Among the various alkyl amine and vegetable oil combinations, triethylenetetramine in coconut oil medium showed the maximum CO2 capture capacity of 72%. The coconut oil used for the process has been recovered, recycled, and reused for 3 cycles. Thus, this novel scheme seems to be a better alternative to conquer the drawback of aqueous amine-based CO2 capture as well as for the capture and utilization of the CO2 gas to gain the value-added products.

Tweaking Electrical and Dielectric Properties of Nickel Oxide Nanocrystals by Varying the Surfactant.

The influence of cationic cetyltrimethylammonium bromide (CTAB) and neutral polymeric polyvinylpyrrolidone (PVP) surfactants on electrical and dielectric properties of NiO nanocrystals is investigated. It is demonstrated that, compressive strain of nanocrystals is higher with PVP than that of CTAB. Consequently surfactant type has significant influence on intrinsic defects of nanocrystals. This is attributed to the difference in stabilization of metallic ions against agglomeration that leads to variation in rate of hydrolysis. Particularly, in the case of PVP assisted synthesis, higher stabilization leads to slow nucleation rate with lower defect density. As a result the hopping time of charge carriers decreases which in turn enhances the conductivity of nanocrystals as evidenced from the shifting of dielectric loss peak to higher frequency.

Influence of alkaline mineralizer on structural and optical properties of ZrO2 nanoparticles.

In this work, the influence of different alkaline mineralizers on structural and optical properties of zirconia nanoparticles synthesized by chemical co-precipitation technique using zirconium oxychloride octahydrate (ZrOCI2 x 8H2O) as precursor is studied. The mineralizers used for the synthesis of nanoparticles are NaOH and NH4OH. X-ray diffraction, Fourier Transform Infrared (FTIR) spectroscopy, UV-visible absorption spectroscopy and Photoluminescence (PL) spectroscopy were used for characterizing the nanoparticles. Structural analysis of the sample synthesized using NaOH shows monoclinic phase as predominant one, however when NH4OH is used the major phases are cubic and tetragonal. The difference is attributed to the number of hydroxyl ions produced and their rate of release during the reaction process. The presence of these phases in both samples is further confirmed by vibrational bands of FT-IR spectra. Also, the low energy bands due to the presence of defects in nanoparticles are also explicitly observed in the photoluminescence spectra. Further the defects lead to a red shift in the band gap of ZrO2 which is observed when the samples are subjected to UV-absorption spectroscopy analysis. It has been demonstrated that zirconia nanoparticles with desired structural properties can be synthesized by changing the type of mineralizer without the necessity of doping.