Protein and Peptide-Based Nanotechnology for Enhancing Stability, Bioactivity, and Delivery of Anthocyanins.

Anthocyanin, a unique natural polyphenol, is abundant in plants and widely utilized in biomedicine, cosmetics, and the food industry due to its excellent antioxidant, anticancer, antiaging, antimicrobial, and anti-inflammatory properties. However, the degradation of anthocyanin in an extreme environment, such as alkali pH, high temperatures, and metal ions, limits its physiochemical stabilities and bioavailabilities. Encapsulation and combining anthocyanin with biomaterials could efficiently stabilize anthocyanin for protection. Promisingly, natural or artificially designed proteins and peptides with favorable stabilities, excellent biocapacity, and wide sources are potential candidates to stabilize anthocyanin. This review focuses on recent progress, strategies, and perspectives on protein and peptide for anthocyanin functionalization and delivery, i.e., formulation technologies, physicochemical stability enhancement, cellular uptake, bioavailabilities, and biological activities development. Interestingly, due to the simplicity and diversity of peptide structure, the interaction mechanisms between peptide and anthocyanin could be illustrated. This work sheds light on the mechanism of protein/peptide-anthocyanin nanoparticle construction and expands on potential applications of anthocyanin in nutrition and biomedicine.

Production Technology and Functionality of Bioactive Peptides.

Bioactive peptides are specific protein fragments that prove health-promoting potential for humans. The bioactivities include antimicrobial, antioxidant, anticancer, immunomodulatory activities, etc. Hence, bioactive peptides' production technology and processes have attracted excessive attention, especially concerning peptides' synthesis, separation, identification, and functionality. This review summarizes the relevant investigations from the above four aspects. Among the production technology of bioactive peptides, biosynthesis, chemosynthesis, technology for separation and purification, and the interactions responsible for peptide-based nanostructures are emphasized. Here, the biosynthesis of peptides includes enzymatic hydrolysis, microbial fermentation, and recombinant DNA technology, and chemosynthesis consists of solution-phase peptide synthesis and solid-phase peptide synthesis (SPPS). The commonly used enzymes in enzymatic hydrolysis are investigated, including pepsin, trypsin, and alcalase. The commonly used microorganisms, typical processes, protein sources, and advantages of microbial fermentation are analyzed. Membrane separation (including ultrafiltration and nanofiltration), chromatography technology (including ion-exchange chromatography, gel filtration chromatography, affinity chromatography, and reverse-phase high-performance liquid chromatography (RP-HPLC)), and electrophoresis technology are detailed for the purification technology. Mass spectrometry (MS), its combination with the high-performance separation method, and nuclear magnetic resonance (NMR) are elucidated for the identification technology. The non-covalent interactions responsible for peptide-based nanostructures involve electrostatic force, hydrogen bonds, π-π stacking, hydrophobic interaction, and van der Waals force. Afterward, we detail the peptides' antihypertensive, antithrombotic, anticancer, antimicrobial, antioxidant, and immunomodulatory activities. The activity analysis mainly involves peptides' sources, structural features, mechanisms of action, and influencing factors. Based on the production and functionality elucidation, potential challenges for peptide application in biomedicine are given. The challenge is analyzed from the aspects of purification and identification technologies and influencing factors of peptides' bioactivities. Our work will elaborate on advances in the production technology of peptides and their bioactivities, which could promote and expand their industrial applications.

Cell Modeling Based on Bubbles with Weighted Membranes.

Mathematicization for cell modeling provides an effective tool to verify the biological theory, and the existing research mainly focuses on the description of cell structures. This article then addresses the pattern question of cell division or morphogenesis by means of bubble model with weighted membranes. In this study, we show that cell shapes including intersection angles at junction points depend on weights on membranes. For convenience, adhesion and contractile force are considered together as a factor in construction of patterning model. This model is also used to compare with experimental data. And the consistency between our model and experiments is also obtained consequently. This system of differential equations with their boundary conditions theorizes the existing experimental models, and improves the rationality of these models.

Sources, health effects and control strategies of indoor fine particulate matter (PM2.5): A review.

Indoor air quality is directly influenced by indoor PM2.5. Short-term and long-term exposure of PM2.5 in the micro environment would severely detriment the health of both humans and animals. The researches both at home and abroad dating from 2000 were analyzed and summarized mainly in the following 3 sections: source apportionment, health effects and control methods. Health effects were illustrated in both epidemiology and toxicology. The epidemiology was explicated in morbidity and mortality, the toxicology was illuminated in inflammatory reaction, oxidative stress, genotoxicity, mutagenicity and carcinogenicity. Control methods were showed in two aspects (sources and means of transmission), of which each was resolved by corresponding control strategy. Abundant investigations indicated that comprehensive control strategies were needed for sources decrement and health burden mitigation of indoor PM2.5. Based on the increasingly wide research of indoor PM2.5, the concept of indoors was essentially expanded, and on the basis of the summary of all the aspects mentioned above, both the scope and depth of indoor PM2.5 research were found insufficiently. Meantime, the potential direction of development in indoor PM2.5 research were projected, in hope of contributing to further relevant study of engineers in ambient environment and building environment.