Development of Cellular High-Protein Foods: Third-Generation Yellow Pea and Red Lentil Puffed Snacks

This study aimed to evaluate how extrusion cooking conditions and microwave heating play a role in enhancing physical and thermal properties of third-generation expanded cellular snacks made from yellow pea (YP) and red lentil (RL) flours for the first time. Increasing temperature and moisture content during extrusion resulted in darker, crunchier and crispier products with higher expansion index (EI). Microwave heating after extrusion led to an increase in cell size and porosity of YP and RL products when qualitatively compared to extrusion alone. Additionally, extrusion followed by microwave heating resulted in extensive damage to starch granular structure and complete denaturation of proteins. Using microwave heating, as a fast and inexpensive process, following partial cooking with extrusion was demonstrated to greatly improve the physical and thermal properties of YP and RL snacks. Microwave heating following mild extrusion, instead of severe extrusion cooking alone, can potentially benefit the development of high quality nutritionally-dense expanded cellular snacks made from pulse flours.

Sensitivity of SARS-CoV-2 towards Alcohols: Potential for Alcohol-Related Toxicity in Humans

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative organism that is highly contagious and has been responsible for more than 240 million cases and 5 million deaths worldwide. Using masks, soap-based hand washing, and maintaining social distancing are some of the common methods to prevent the spread of the virus. In the absence of any preventive medications, from the outset of pandemic, alcohol-based hand sanitizers (ABHS) have been one of the first-line measures to control transmission of Coronavirus Disease 2019 (COVID-19). The purpose of this narrative review is to evaluate the sensitivity of SARS-CoV-2 towards ABHS and understand their potential adverse effects on humans. Ethanol and isopropanol have been the most commonly used alcohols in ABHS (e.g., gel, solution, spray, wipes, or foam) with alcohol in the range of 70–85% v/v in World Health Organization or Food and Drug Administration-approved ABHS. The denaturation of proteins around the envelope of SARS-CoV-2 positive sense single-stranded RNA virus is the major mechanism of action of ABHS. Due to frequent use of high-percentage alcohol-containing ABHS over an extended period of time, the oral, dermal, or pulmonary absorption is a possibility. In addition to the systemic toxicity, topical adverse effects such as contact dermatitis and atopic dermatitis are plausible and have been reported during COVID-19. ABHS appear to be effective in controlling the transmission of SARS-CoV-2 with the concern of oral, dermal, or pulmonary absorption.

Terahertz Driven Ultrafast Energy Dissipation in Aqueous Ionic Solutions

Solvation of ions changes the physical, chemical and thermodynamic properties of water. The microscopic origin of this process is believed to be the ion-induced perturbation in the structure and dynamics of the hydrogen (H)-bonding network of water. Here, we provide microscopic insight on the local structural deformation of the H-bonding network of water by ions, via investigating the dissipation of external energy in salt solutions by a novel time-resolved terahertz (THz)-Raman spectroscopy. We resonantly drive the low-frequency rotational dynamics of water molecules by intense THz pulses and probe the Raman response of their intermolecular translational motions. We find that the intermolecular rotational-to-translational energy transfer is enhanced by highly-charged cations and it is drastically reduced by highly-charged anions, scaling with the ion surface charge density and concentration. Our molecular dynamics simulations further reveal that the water-water H-bond strength between the first and the second solvation shells of cations (anions) increases (decreases), signifying the opposite effects of cations and anions on the local structure of water. The impact of ion polarity on the ultrafast energy dissipation in water, resembles the effect of ions on stabilization and denaturation of proteins.

Implicit water model within the Zimm-Bragg approach to analyze experimental data for heat and cold denaturation of proteins

Studies of biopolymer conformations essentially rely on theoretical models that are routinely used to process and analyze experimental data. While modern experiments allow study of single molecules in vivo, corresponding theories date back to the early 1950s and require an essential update to include the recent significant progress in the description of water. The Hamiltonian formulation of the Zimm-Bragg model we propose includes a simplified, yet explicit model of water-polypeptide interactions that transforms into the equivalent implicit description after performing the summation of solvent degrees of freedom in the partition function. Here we show that our model fits very well to the circular dichroism experimental data for both heat and cold denaturation and provides the energies of inter- and intra-molecular H-bonds, unavailable with other processing methods. The revealed delicate balance between these energies determines the conditions for the existence of cold denaturation and thus clarifies its absence in some proteins.

Fluorescent Detection of the Target Protein via a Molecularly Imprinted Hydrogel

Proteins are typically separated by immune-reaction, such as enzyme-linked immuno sorbent assay, and detected by certain fluorescent labeling. They have usually potential of complicated procedures, denaturation of proteins by labeling,...

Determining the degree of denaturation of bovine serum albumin using a new UV analysis technique

There is a lack of fast and inexpensive analysis methods to study the conformational changes and the degree of denaturation of proteins quantitatively. As such, a novel analytical technique is developed based on the ultraviolet-visible (UV-Vis) absorption spectrum of proteins, and a mathematical modeling of the results. The phenomenon behind this technique is the shift of the absorption peak of amino acid residues of BSA such as tyrosine, phenylalanine, and tryptophan as the protein unfolds and these residues are exposed to the solvent. However, the portion of the peak that is shifted is miniscule and it can be enhanced by using the proposed technique in this paper. As an example, we also show how this technique was applied for evaluating the temperature effects on thermal denaturation of bovine serum albumin (BSA) protein. A degree of denaturation curve as a function of time was obtained at three different temperatures using this technique. The results are reproducible and consistent with those reported in the literature. This technique is especially recommended for analyses where several tests are needed quickly, and the amount of sample is limited. Among the applications, it can be used for evaluation of disinfection through assessing the degree of denaturation for pathogens proteins.