Compound Histories: Materials, Governance and Production, 1760-1840 explores the intertwined realms of production, governance and materials, placing chemists and chemistry at the center of processes ...most closely identified with the construction of the modern world. Readership: All interested in European history since the mid-eighteenth century, and anyone interested in the history of industrialization, science, technology, modernization, political economy, environmental history, materials and governance.
Marine natural products Blunt, John W; Copp, Brent R; Keyzers, Robert A ...
Natural product reports,
03/2017, Letnik:
34, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Covering: 2015. Previous review: Nat. Prod. Rep., 2016, 33, 382-431This review covers the literature published in 2015 for marine natural products (MNPs), with 1220 citations (792 for the period ...January to December 2015) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1340 in 429 papers for 2015), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
Industrial Applications of Ionic Liquids Greer, Adam J; Jacquemin, Johan; Hardacre, Christopher
Molecules (Basel, Switzerland),
11/2020, Letnik:
25, Številka:
21
Journal Article
Recenzirano
Odprti dostop
Since their conception, ionic liquids (ILs) have been investigated for an extensive range of applications including in solvent chemistry, catalysis, and electrochemistry. This is due to their ...designation as designer solvents, whereby the physiochemical properties of an IL can be tuned for specific applications. This has led to significant research activity both by academia and industry from the 1990s, accelerating research in many fields and leading to the filing of numerous patents. However, while ILs have received great interest in the patent literature, only a limited number of processes are known to have been commercialised. This review aims to provide a perspective on the successful commercialisation of IL-based processes, to date, and the advantages and disadvantages associated with the use of ILs in industry.
•Two water-soluble polysaccharides were extracted from the Tunisian brown alga C. compressa.•The sulfated fucoidan was a galactofucan with a backbone of α-(1,3) and α-(1,4)-l-Fucp, highly ...substituted.•The sodium alginate showed a M/G ratio closed to 0.77 and the ability to form solid and rigid gel.•The polysaccharides displayed antioxidant activities with IC50 values under 560 μg/mL.
A fucoidan (CCF) and a sodium alginate (CCSA) were extracted and purified from the Tunisian brown seaweed Cystoseira compressa. CCF was a highly sulfated heterogalactofucan composed of α-(1→3), α-(1→4)-linked l-Fucp as main backbone which could be highly branched (31.84%) at O-3 and O-4 positions of α-(1→4)-l-Fucp and α-(1→3)-l-Fucp by terminal monosaccharides and side chains such as terminal α-l-Fucp, terminal β-d-Galp, β-d-Galp-(1→3)-α-l-Fucp and β-d-Galp-(1→4)-α-l-Fucp. The ratio of α-(1→3)/α-(1→4) linkages was estimated at 3.86:1. CCSA was characterized by HPAEC-PAD, GC/MS-EI, ATR-FTIR, and 1H-NMR. The M/G ratio was M/G = 0.77, indicating that CCSA respectively contained 44% and 56% of mannuronic and guluronic acids. The values of FGG, FMM, FGM (or FMG) blocks as well as the parameter η were estimated. The two polysaccharides exhibited effective antioxidant activities by ferrous ion chelation, ferric ion reduction and DPPH radical-scavenging, outlining their potentials as natural additives.
Flavonoids are phytochemical compounds present in many plants, fruits, vegetables, and leaves, with potential applications in medicinal chemistry. Flavonoids possess a number of medicinal benefits, ...including anticancer, antioxidant, anti-inflammatory, and antiviral properties. They also have neuroprotective and cardio-protective effects. These biological activities depend upon the type of flavonoid, its (possible) mode of action, and its bioavailability. These cost-effective medicinal components have significant biological activities, and their effectiveness has been proved for a variety of diseases. The most recent work is focused on their isolation, synthesis of their analogs, and their effects on human health using a variety of techniques and animal models. Thousands of flavonoids have been successfully isolated, and this number increases steadily. We have therefore made an effort to summarize the isolated flavonoids with useful activities in order to gain a better understanding of their effects on human health.
A method to assemble stimuli-responsive nucleic acid-based hydrogel-stabilized microcapsule-in-microcapsule systems is introduced. An inner aqueous compartment stabilized by a stimuli-responsive ...hydrogel-layer (∼150 nm) provides the inner microcapsule (diameter ∼2.5 μm). The inner microcapsule is separated from an outer aqueous compartment stabilized by an outer stimuli-responsive hydrogel layer (thickness of ∼150 nm) that yields the microcapsule-in-microcapsule system. Different loads, e.g., tetramethyl rhodamine-dextran (TMR-D) and CdSe/ZnS quantum dots (QDs), are loaded in the inner and outer aqueous compartments. The hydrogel layers exist in a higher stiffness state that prevents inter-reservoir or leakage of the loads from the respective aqueous compartments. Subjecting the inner hydrogel layer to Zn2+-ions and/or the outer hydrogel layer to acidic pH or crown ether leads to the triggered separation of the bridging units associated with the respective hydrogel layers. This results in the hydrogel layers of lower stiffness allowing either the mixing of the loads occupying the two aqueous compartments, the guided release of the load from the outer aqueous compartment, or the release of the loads from the two aqueous compartments. In addition, a pH-responsive microcapsule-in-microcapsule system is loaded with glucose oxidase (GOx) in the inner aqueous compartment and insulin in the outer aqueous compartment. Glucose permeates across the two hydrogel layers resulting in the GOx catalyzed aerobic oxidation of glucose to gluconic acid. The acidification of the microcapsule-in-microcapsule system leads to the triggered unlocking of the outer, pH-responsive hydrogel layer and to the release of insulin. The pH-stimulated release of insulin is controlled by the concentration of glucose. While at normal glucose levels, the release of insulin is practically prohibited, the dose-controlled release of insulin in the entire diabetic range is demonstrated. Also, switchable ON/OFF release of insulin is achieved highlighting an autonomous glucose-responsive microdevice operating as an “artificial pancreas” for the release of insulin.
The design of slippery liquid‐infused porous surfaces (SLIPS) using nanoporous and chemically reactive polymer multilayers is reported. This approach permits fabrication of slippery anti‐fouling ...coatings on complex surfaces and provides new means to manipulate the mobilities of contacting aqueous fluids. The results expand the range of tools that can be used to manipulate the behaviors of SLIPS and open the door to new applications of this emerging class of soft materials.
In this study, leaves of three indigenous varieties of Mulberry namely, Morus alba L., Morus nigra L. and Morus rubra L. were investigated for their antioxidant potential and their proximate ...composition was determined. The yields of 80% methanolic extracts ranged between 8.28-13.89%. The contents of total phenolics (TPC), total flavonoids (TFC) and ascorbic acid (AA) ranged between 16.21-24.37 mg gallic acid equivalent (GAE)/g, 26.41-31.28 mg rutin equivalent (RE)/g and 0.97-1.49 mg/g, respectively. The antioxidant activity of leaf extracts was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) radical scavenging actity, 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid (ABTS(•+)) radical cation scavenging capacity and ferric ion reducing power and values ranged between 1.89-2.12, 6.12-9.89 and 0.56-0.97 mM Trolox equivalent/g of dried leaves, respectively. The investigated features reveal good nutritive and antioxidant attributes of all the varieties with mutually significant differences.
Graphene oxide (GO) crosslinked nanocomposites hydrogels (NCH) of chitosan (CS) and carboxymethyl cellulose (CMC) were synthesized and the feasibility of its application as a versatile adsorbent for ...the remediation of cationic (methylene blue, MB) as well as anionic (methyl orange, MO) dyes contaminated wastewater was explored. Initially, GO was functionalized with vinyltriethoxysilane which was subsequently used as a chemical crosslinker to synthesize the NCH of CS and CMC (CS/CMC-NCH) with the polymeric mixture of diallyldimethylammonium chloride and 2-acrylamido-2-methyl-1-propanesulfonic acid. About 99% dye was adsorbed from 50 mg/L dye solution of MB dye with 0.4 g/L of CS/CMC-NCH at pH 7, whereas, for MO about 82% dye was adsorbed with 0.6 g/L of CS/CMC-NCH at pH 3. The Adsorption of both dyes is well explained using pseudo-second-order and Langmuir models with the maximum adsorption capacities of 655.98 mgdye/gads for MB and 404.52 mgdye/gads for MO. Thermodynamics studies suggested spontaneous and exothermic nature of the adsorption process with values of ΔS < 0 and ΔH > 0. Furthermore, CS/CMC-NCH showed excellent regeneration capacity for continuous twenty cycles of adsorption-desorption. Therefore, the synthesized CS/CMC-NCH is a versatile adsorbent that can treat both anionic and cationic dyes contaminated wastewater.
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•GO-VTES crosslinked NCH of chitosan and carboxymethyl cellulose were synthesized.•CS/CMC-NCH adsorbed methylene blue and methyl orange dyes.•Adsorption process was expressed with Langmuir and pseudo-second-order models.•Thermodynamic parameters showed the spontaneous and exothermic adsorption.•Regeneration studies indicated the high reuse efficiency upto twenty cycles.
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