Quantifying impact of the low-cost SERS substrate on SERS signal

Surface-Enhanced Raman Spectroscopy (SERS) allows structural detection of molecules absorbed on rough noble metal surfaces by amplifying a normally weak Raman signal. It can be applied in forensic science, biosensing, food safety, and medical diagnostics [1]. Although costly gold and silver films are used as SERS substrates, AuNPs (gold nanoparticles) on aluminum foil can become a low-cost alternative

Thioester Synthesis By a Designed Nickel Enzyme Models Prebiotic Energy Conversion

The formation of carbon-carbon bonds from prebiotic precursors such as carbon dioxide represents the foundation of all primordial life processes. In extant organisms, this reaction is carried out by the carbon monoxide dehydrogenase (CODH)/acetyl coenzyme A synthase (ACS) enzyme, which performs the cornerstone reaction in the ancient Wood-Ljungdahl metabolic pathway to synthesize the key biological metabolite, acetylCoA. Despite its significance, a fundamental understanding of this transformation is lacking, hampering efforts to harness analogous chemistry. To address these knowledge gaps, we have designed an artificial metalloenzyme within the azurin protein scaffold as a structural, functional, and mechanistic model of ACS. We demonstrate the intermediacy of the NiI species and requirement for ordered substrate binding in the bioorganometallic carbon-carbon bond-forming reaction from the one-carbon ACS substrates. The electronic and geometric structures of the nickel-acetyl intermediate have been characterized using time-resolved optical, electron paramagnetic resonance, and X-ray absorption spectroscopy in conjunction with quantum chemical calculations. Moreover, we demonstrate that the nickel-acetyl species is chemically competent for selective acyl transfer upon thiol addition to biosynthesize an activated thioester. Drawing an analogy to the native enzyme, a mechanism for thioester generation by this ACS model has been proposed. The fundamental insight into the enzymatic process provided by this rudimentary ACS model has implications for the evolution of primitive ACS-like proteins. Ultimately, these findings offer strategies for development of highly active catalysts for sustainable generation of liquid fuels from one-carbon substrates, with potential for broad applications across diverse fields ranging from energy storage to environmental remediation

Quantifying impact of the low-cost SERS substrate on SERS signal

Surface-Enhanced Raman Spectroscopy (SERS) allows structural detection of molecules absorbed on rough noble metal surfaces by amplifying a normally weak Raman signal. It can be applied in forensic science, biosensing, food safety, and medical diagnostics [1]. Although costly gold and silver films are used as SERS substrates, AuNPs (gold nanoparticles) on aluminum foil can become a low-cost alternative

Study of Quality Indicators of Oil and Fat Products Made From a Mixture of Vegetable Oils

This article is devoted to the development of mayonnaise with a balanced composition. It occupies 3.3 % of the human diet on the daily market. Despite the growth of the range of mayonnaise over the past year, the problem of manufacturing domestic mayonnaise of a balanced composition that meets all the requirements for this type of product remains relevant. A comprehensive multi-level approach to assessing the nutrition of the Kazakh people revealed a wide range of nutritional status disorders. In particular, these include the consumption of animal fats and a deficiency of polyunsaturated fatty acids. Polyunsaturated fatty acids are essential nutrition factors and their composition should correspond to 3-4% of the energy value of the diet. A new functional mayonnaise product with a balanced composition of ɷ-3 and ɷ-6 fatty acids based on a mixture of vegetable oils (sunflower, linseed, and safflower) with a balanced composition of polyunsaturated fatty acids has been developed. The main physical and chemical characteristics of a sample of a mixture of vegetable oils have been determined. In laboratory conditions, NPJSC "KazNARU" produced a prototype of mayonnaise based on a mixture of vegetable oils and determined their physicochemical and organoleptic characteristics. It was found that in terms of physical, chemical and organoleptic characteristics, the resulting mayonnaise product fully meets the requirements of regulatory documents