Pollution of water resources by various pollutants is a global environmental issue, particularly, dye pollution has a major contribution to it. From various studies, it is confirmed that adsorption is an excellent remediation technique compared to others. Mg−Allayered double hydroxides (LDHs) intercalated with NO 3 − ions act as an effective adsorbent-removing ionic species like heavy metal and dyes. Another popular nanomaterial is graphene oxide (GO), which is successfully used as an adsorbent for different pollutants like dye and heavy metal ions. It is prepared based on the modified Hummers method. In this study, GO was introduced on the surface of LDH to improve its adsorption capacity. The adsorption process is well described by the Freundlich model. The maximum adsorption capacity was obtained at around 0.5 and 0.85 mmol of methylene blue (MB) per gram of Mg−Al LDH and modified Mg−Al LDH with GO, respectively. The reaction kinetics of MB with both adsorbents is determined to be the pseudo-second-order. To get more insights of the mechanism, molecular dynamics (MD) simulation was conducted among the modified Mg−Al LDH with GO and MB molecules at both low-and high-concentration environments, which demonstrated that the developed composite adsorbs MB molecules predominantly onto its GO surface and then the MB molecules are adsorbed by the LDH surface. C−H•••O (2.49−3.04 Å) and pi-donor•••H−O (2.45−3.05 Å) are the major driving forces behind the strong adsorbability. Besides, S•••H−O, S•••O,N•••O−H, pi•••lone pair, pi•••sigma, pi•••cation, and alkyl•••hydrophobic interactions play important roles in stabilizing the MB molecules onto the surface of the composite.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

No abstract

Anethum sowa Roxb., (a well-known herb in folk medicine, has a greater medicinal significance due to its diversified activities such as antioxidant, antimicrobial and antispasmodic activity. Very few bioactive compounds have been reported from this species. Our study focused on the isolation, structure elucidation and bioactivity assay of the compounds. In the present work, 6-hydroxy-1, 3-dimethoxy-7-methyl-xanthen-9-one (AS-1) from dichloromethane extract and scopoletin (AS-2), 1, 3, 4-trimethoxy-xanthen-9-one (AS-3), graveolone (AS-4) from ethyl acetate extract of stem of A. sowa were isolated from the stem as well as the plant for the first time. All the characterizations and chemical structures of the compounds were determined by extensive modern spectroscopic techniques such as ultraviolet (UV), infrared (IR), mass, Nuclear Magnetic Resonance (NMR) spectrophotometer. Moreover, the cytotoxic, antimicrobial and antioxidant activity of AS-2, AS-3 and AS-4 were assessed. AS-2 exhibited significant activity against Salmonella typhi while mild antifungal activity against Aspergillus niger. Furthermore AS-3 revealed significant antifungal activity against Sacharomyces cerevacae as well as antibacterial activity against Salmonella typhi. Besides AS-4 exhibited moderate antibacterial activity against Bacillus megaterium. In addition AS-2, AS-3 and AS-4 presented mild cytotoxic with respect to positive control (Vincristine sulphate) while AS-3 exhibited moderate antioxidant activity as compared to positive control (Ascorbic acid).