Synthesis of nanosilver loaded chitosan/poly(acrylamide-co-itaconic acid) based inter-polyelectrolyte complex films for antimicrobial applications

Exploration of magnetic zeolite thin film derived from coal fly ash an efficient sorbent: Application to water treatment

Fly ash, produced during coal combustion for energy making, which is recognized as an industrial by-product, could lead to environmental health hazards. Subsequently, fly ash found that an exceptional adsorption performance for the removal of various toxic pollutants, the adsorption capacity of fly ash might be altered by introducing physical/chemical stimulation. Successfully converting fly ash into zeolites not only recovers their disposal difficulties but also transforms unwanted materials into merchandisable products for various industrial applications. Here we fabricated that, converting fly ash into zeolite and then modifying it with aminopropyl imidazole (ionic liquid), the imidazolium-based zeolite will be used as a template for loading Fe3O4 NPs. The formation of Fe3O4 NPs decorated zeolites is incorporated with polymeric materials [including polystyrene sulphonate (PSS), polyvinyl alcohol (PVA) and chitosan], producing to magnetic film (named Fe3O4 NPs@zeolite film). The fabricated magnetic film exhibits excellent functionality and durability for the sorption of chromium, selenium and organic dyes such as Congo red, RhB. These toxic contaminates were electrostatically bonded through adsorbent due to their protonation of below the pHzpc 7.0 with surface functional groups from imidazolium cationic moiety (R-N+), amino groups derived chitosan (-N, -NH and -NH2), and hydroxyl groups (Fe-OH), electrostatically bind with anionic selenium species are [(SeO32-, Se(IV)), and (SeO42- Se(VI)], chromium species HCrO4-, Cr2O72- and CrO42- the maximum removal performance were achieved in a wide pH range are highly suitable for practical application.

Reprogramming Yarrowia lipolytica metabolism for efficient synthesis of itaconic acid from flask to semipilot scale

Itaconic acid is an emerging platform chemical with extensive applications. Itaconic acid is currently produced by Aspergillus terreus through biological fermentation. However, A. terreus is a fungal pathogen that needs additional morphology controls, making itaconic acid production on industrial scale problematic. Here, we reprogrammed the Generally Recognized As Safe (GRAS) yeast Yarrowia lipolytica for competitive itaconic acid production. After preventing carbon sink into lipid accumulation, we evaluated itaconic acid production both inside and outside the mitochondria while fine-tuning its biosynthetic pathway. We then mimicked the regulation of nitrogen limitation in nitrogen-replete conditions by down-regulating NAD+-dependent isocitrate dehydrogenase through weak promoters, RNA interference, or CRISPR interference. Ultimately, we optimized fermentation parameters for fed-batch cultivations and produced itaconic acid titers of 130.1 grams per liter in 1-liter bioreactors and 94.8 grams per liter in a 50-liter bioreactor on semipilot scale. Our findings provide effective approaches to harness the GRAS microorganism Y. lipolytica for competitive industrial-scale production of itaconic acid.

World market and biotechnological production of itaconic acid

The itaconic acid (IA) world market is expected to exceed 216 million of dollars by 2020 as a result of an increasing demand for bio-based chemicals. The potential of this organic acid produced by fermentation mainly with filamentous fungi relies on the vast industrial applications of polymers derived from it. The applications may be as a superabsorbent polymer for personal care or agriculture, unsaturated polyester resin for the transportation industry, poly(methyl methacrylate) for electronic devices, among many others. However, the existence of other substitutes and the high production cost limit the current IA market. IA manufacturing is done mainly in China and other Asia-Pacific countries. Higher economic feasibility and production worldwide may be achieved with the use of low-cost feedstock of local origin and with the development of applications targeted to specific local markets. Moreover, research on the biological pathway for IA synthesis and the effect of medium composition are important for amplifying the knowledge about the production of that biochemical with great market potential.