Synthesis of polyaspartic acid-capped 2-aminoethylamino acid as a green water treatment agent and study of its inhibition performance and mechanism for calcium scales

Recombinant Multi-l-Arginyl-Poly-l-Aspartate (Cyanophycin) as an Emerging Biomaterial

Multi-l-arginyl-poly-l-aspartate (MAPA) is a non-ribosomal polypeptide which synthesis is directed by cyanophycin synthetase, and its production can be achieved using recombinant microorganisms carrying the cphA gene. Along its poly-aspartate backbone, arginine or lysine links to each aspartate via an isopeptide bond. MAPA is a zwitterionic polyelectrolyte full of charged carboxylic, amine, and guanidino groups. In aqueous solution, MAPA exhibits dual thermal and pH responses similar to those stimuli-responsive polymers. Being biocompatible, the films containing MAPA can support cell proliferation and elicits minimal immune response in macrophages. Dipeptides from MAPA after enzymatic treatments can provide nutritional benefits. In light of the increasing interest in MAPA, this article focuses on the recent discovery of the function of cyanophycin synthetase and the potentials of MAPA as a biomaterial.

The oligosuccinimide and modified polysuccinimide as green corrosion and scale inhibitors

Corrosion and scale formation are crucial issues in the petroleum industry. They can inflict metal or other materials breakdown, leading to environmental pollution. Applying scale and corrosion inhibitors is a cost-effective and efficient way of controlling corrosion and scale formation in a fluid system. Much research has been conducted to obtain cheap and safe corrosion or scale inhibitors. Modified polysuccinimides (PSI) are among the organic compounds reported as effective and environmentally friendly corrosion as well as scale inhibitors. The use of various novel green corrosion and scale inhibitors from modified PSI for controlling corrosion reactions or scale formation has not been extensively reviewed. Hence, this review highlights recent studies on preparing PSI/OSI, modifying PSI, and analyzing their performance as corrosion and scale inhibitors. Adsorption study, biodegradation performance, computational quantum study, limitations, and prospects of the inhibitors are also discussed. Therefore, i this work provides an overview of novel modified PSI as effective and safe corrosion or scale inhibitors in different media, for various metals, and on a different scale.