Biotechnology and Bioprocess Engineering最新文献

A continuous purification process can be beneficial to the purification of biologics due to its higher productivity and efficiency than a conventional batch purification process. However, regulatory issues and lack of established cases render deployment of the continuous process difficult in industrial settings. Here we report a case study for design and optimization of an advanced continuous process for purifying a low-titer enzyme as a model biologic. To convert a conventional batch process to an advanced continuous one in purification of biologics, conventional unit operations (UOs), including ultrafiltration/diafiltration (UF/DF) and batch chromatography, were replaced by advanced ones such as in-line dilution conditioning (IDC) and periodic counter-current chromatography (PCC). The UF/DF UO was changed to IDC UO to adjust pH and conductivity. The mixing ratio of the sample and the conditioning buffer in IDC was determined by experiments with three buffers. PCC was optimized with two variables, column height and sample loading residence time, as the delta pressure in the columns was less than 1.0 bar. A graph indicating the operating area was plotted to efficiently control the PCC. Although the sample volume increased in IDC, PCC had a complementary advantage in that purification was performed faster than batch chromatography. We observed at least 25% increase in economic advantage when the advanced continuous process was applied to purify a low-titer enzyme. We propose not only a continuous process with the substitution of UF/DF and batch chromatography with IDC and PCC but also a method to optimize PCC by plotting operating areas.

Abstract

Researchers have made significant efforts to attach peptides to various biomaterials, resulting in diverse functionalities. By harnessing the advantages of peptides, functions such as high specificity, potency, cost-effectiveness, small size for improved tissue penetration and targeted delivery, biodegradability, and novel therapeutic applications can be achieved through their attachment to biomaterials. Of various methods available for modifying biomolecules, chemical techniques are the most established and can effectively immobilize the desired molecule onto a specific surface. This article provides a comprehensive overview of the chemical modification methods used for attaching peptides to various biomaterials in recent studies and showcases some of their latest applications.

Abstract

While personalized cancer therapies have improved treatment efficacy for specific cancer types, cancers with unclear genetic factors remain a challenge. Gold nanorods (GNRs) have gained attention as cancer therapies due to their anticancer effects even without light irradiation. This study investigates the anticancer effects of citrate-stabilized gold nanorods (CGNRs) on melanoma cell lines and tumors, as well as the factors influencing their efficacy. The study found that CGNRs exhibited strong sensitivity in specific cancer cells but not in normal cells. Cell viability analysis showed that CGNRs induce cell death in a concentration-dependent manner, and their anticancer effects are mainly due to necrosis. In vivo experiments using a murine melanoma model showed that intratumoral administration of CGNRs significantly suppressed tumor growth without body weight loss. Interestingly, our results suggest that the anticancer effects of CGNRs were independent of their cellular uptake efficiency but may be highly correlated with the aggressiveness of cancer cells. Overall, the results suggest that CGNRs have promising potential as a specific treatment for melanoma, especially for aggressively proliferating cells, and may represent an alternative or complementary therapy to conventional chemotherapy.

Abstract

Oysters are rich nutrition sources that contain polysaccharides, proteins, peptides, phenolic compounds, minerals, and vitamins. In the search for compounds that exert anti-inflammatory effects in macrophages, we prepared hydrolyzed oyster (Magallana gigas) extracts (HOE) and evaluated their protective effects against inflammation and oxidative stress in RAW264.7 murine macrophages treated with lipopolysaccharide (LPS). As expected, LPS notably stimulated the generation of inflammatory molecules and associated regulatory proteins. However, HOE effectively blocked these effects in a concentration-dependent manner. This suppressive effect of HOE on inflammation appears to be responsible for blocking nuclear factor-κB (NF-κB) signaling. In addition, LPS-mediated reactive oxygen species generation RAW264.7 cells was highly inhibited by HOE treatment, which appears to be partially regulated by nuclear factor erythroid 2-related factor 2 (Nrf2). Moreover, HOE at high concentrations inhibited pro-inflammatory mediators and cytokines to a greater extent than BAY7085, a pharmacological NF-κB inhibitor, in LPS-treated RAW264.7 cells. Taken together, our results show that HOE effectively inhibits inflammation and oxidative stress via modulating the NF-κB and/or Nrf2 signaling in RAW264.7 macrophages and can be a potential therapeutic agent to prevent inflammation-related diseases.

Enzyme-linked immunosorbent assays (ELISA) have been widely used to detect disease-related antigens in clinical and research laboratories. One of the main drawbacks of ELISA is the utilization of physical adsorption for immobilizing antibodies on a surface, causing low sensitivity, reproducibility, and precision. In this study, we applied a BC-MAP linker composed of antibody-immobilizing BC domains of protein A and surface-adhesive mussel adhesive protein (MAP) to an ELISA platform to overcome these limitations. The performance of ELISA using BC-MAP linker was compared with that of untreated ELISA. BC-MAP proteins were reproducibly coated to the surface while exposing BC domains, resulting in twofold higher sensitivity and improved reproducibility of ELISA compared to the untreated ELISA utilizing physical adsorption of antibodies. Thus, the proposed method could be successfully used in ELISA platforms to diagnose and manage diseases.

Rice protein, a high-quality protein, contains all of its essential amino acids, and its amino acid composition is consistent with the ideal pattern recommended by the Food and Agriculture Organization/World Health Organization. Rice protein-derived products as feed additives have rather low added value. Rice protein hydrolysates (RPHs) are valuable products that can be generated from underutilized rice protein. In the RPH, oligopeptide-enriched RPH and its oligopeptides have been proposed as superior candidates for improving absorption and bioavailability and have potential broad application. Thus, this review outlines the absorption behavior, bioactivity, and preparation of rice oligopeptides. The structure-bitterness relationships and debittering of these materials are discussed in detail, as are their safety and allergenicity. Additionally, the applications of rice oligopeptides in the food and pharmaceutical industries as functional ingredients are also highlighted.

Abstract

Microencapsulation of human mesenchymal stromal cells (MSCs) via electrospraying has been well documented in tissue engineering and regenerative medicine. Herein, we report the use of microencapsulation via electrospraying, for MSC expansion using a commercially available hydrogel that is durable, optimized to MSC culture, and enzymatically degradable for cell recovery. Critical parameters of the electrospraying encapsulation process such as seeding density, correlation of microcapsule output with hydrogel volume, and applied voltage were characterized to consistently fabricate cell-laden microcapsules of uniform size. Upon encapsulation, we quantified ~ 10× expansion of encapsulated MSCs within a vertical-wheel bioreactor, and verified the preservation of critical quality attributes including immunophenotype and multipotency after expansion and cell recovery. Finally, we highlight the genetic manipulation of encapsulated MSCs as an example of incorporating bioactive agents in the microcapsule to create new compositions of MSCs with altered phenotypes.

Artificial transplantation of the human body, which requires high technology, has been an attractive issue in the 4th industrial revolution era. The artificial equipment for human applications could contain a small-scale power supply. Enzyme fuel cells (EFCs) that generate green energy are being researched for use as the power supply for pacemakers, insulin pump, and retinal implant in human body. This study focused on an (EFC) using thin film electrodes-based on enzyme immobilization technology. The performance of this EFC was improved by enzyme immobilization and electron transfer. To improve the electron transfer, the GO/Co/chitosan composite was modified on the surface of thin film electrode. The properties of this modified surface of thin film electrode were confirmed by analysis of field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy, and atomic force microscopy. The performance of the designed EFC was optimized with immobilized redox enzyme on the modified electrode. The highest power density and voltage are determined as 441.48 µW/cm² and − 0.443 V by thin film electrode, respectively. The optimum conditions of the EFC were 0.1 M D-glucose, 0.1 g/L glucose oxidase, pH 7.0, and reaction time of 4 h for both two types of thin film-electrodes.