Multiple Regulatory Mechanisms Synergistically Control the Soluble Expression of CE for Enhanced Enzymatic Productivity of Lactulose in .

The limited expression of cellobiose 2-epimerase poses a significant constraint on the industrial enzymatic production of lactulose. Extensive modifications to the expression cassette offer a means to enhance the yield of recombinant proteins. In this study, an integrated strategy, combining individual and collaborative approaches, is proposed to fine-tune each stage of the CE overexpression program.

[Recent advances in metabolic engineering of microorganisms for production of tyrosol and its derivatives].

Tyrosol is a natural phenolic compound with antioxidant, anti-inflammatory and other biological activities, serving as an important precursor of high-value products such as hydroxytyrosol and salidroside. Therefore, the green and efficient biosynthesis of tyrosol and its derivatives has become a research hotspot in recent years. Building cell factories by metabolic engineering of microorganisms is a potential industrial production way, which has low costs and environmental friendliness.

Regulatory effect of β-glucan secreted by on triglyceride metabolism and their relationships with the modulation of intestinal microbiota in mice fed a high-fat diet.

The present study investigated the regulatory effects of β-glucan secreted by (RPG) on triglyceride metabolism and gut microbiota in mice fed a high-fat diet. The results indicated that supplementation with RPG significantly reduced body weight gain, blood glucose levels, and the tissue index of epididymal white adipose tissue (eWAT) and subcutaneous adipose tissue (SAT). Conversely, it increased the tissue index of brown adipose tissue (BAT).

Inverse metabolic engineering based on metabonomics for efficient production of hydroxytyrosol by Saccharomyces cerevisiae.

Metabolic engineering provides a powerful approach to efficiently produce valuable compounds, with the aid of emerging gene editing tools and diverse metabolic regulation strategies. However, apart from the current known biochemical pathway information, a variety of unclear constraints commonly limited the optimization space of cell phenotype. Hydroxytyrosol is an important phenolic compound that serves various industries with prominent health-beneficial properties.

Highly efficient production and simultaneous purification of d-tagatose through one-pot extraction-assisted isomerization of d-galactose.

A one-pot extraction-assisted d-galactose-to-d-tagatose isomerization strategy was proposed based on the selective extraction of d-tagatose by phenylborate anions. 4-Vinylphenylboronic acid was selected with high extraction efficiency and selectivity towards d-tagatose. The extracted sugars could be desorbed through a two-staged stripping process with the purity of d-tagatose significantly increased.

A precise swaying map for how promiscuous cellobiose-2-epimerase operate bi-reaction.

Promiscuous enzymes play a crucial role in organism survival and new reaction mining. However, comprehensive mapping of the catalytic and regulatory mechanisms hasn't been well studied due to the characteristic complexity. The cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus (CsCE) with complex epimerization and isomerization was chosen to comprehensively investigate the promiscuous mechanisms.

Efficient Secretory Production of δ-Tocotrienol by Combining Pathway Modularization and Transportation Engineering.

The vitamin E component δ-tocotrienol has shown impressive activities in radioprotection, neuroprotection, and cholesterol reduction. Its production is limited by the low content in plants and difficulty in separation from other tocotrienols. Fermentative production using a microbial cell factory that exclusively produces and secretes δ-tocotrienol is a promising alternative approach.

Precise Photothermal Treatment of Methicillin-Resistant Infection via Phage Lysin-Cell Binding Domain-Modified Gold Nanosheets.

The increasing spread of antibiotic resistance in bacterial pathogens poses a huge threat to global human health. Precise targeting of bacterial pathogens while avoiding collateral damage to healthy tissues has become the overriding goal for bacterial infection treatment. Inspired by the host specificity of bacteriophages, a biomimetic intelligent platform was designed for highly precise photothermal treatment herein.

Reshaping the Binding Pocket of Cellobiose 2-Epimerase for Improved Substrate Affinity and Isomerization Activity for Enabling Green Synthesis of Lactulose.

Enzymatic isomerization of lactose into lactulose via cellobiose 2-epimerase (CE) could provide an eco-friendly route for the industrial production of lactulose, a valuable food prebiotic. However, poor substrate affinity for lactose and preference for epimerization over isomerization hinder this application. Previous studies on CE improvement have focused on random mutagenesis or active site rational design; little is known about the relationship between substrate binding and enzyme efficacy, which was hence the subject of this study.

Pulsed electric field as a promising technology for solid foods processing: A review.

A pulsed electric field (PEF) induces cell electroporation for solid foods, thereby allowing PEF to be used as a pretreatment method for extraction, drying, peeling, freeze-thawing, and cooking by increasing mass transfer. Currently, popular research mainly focuses on the process and results of the application of PEF to solid food processing. Therefore, this review summarizes the impact of PEF on the quality of solid food, the evaluation techniques of PEF-treated tissues and the characteristics of PEF treatment chambers.

Reduction of intestinal fat digestion and absorption by β-glucan secreted by interference in triglyceride hydrolysis.

In this study, the ability of β-glucan extracted from to reduce digestion and absorption of ingested fat was systematically investigated and experiments. Specifically, in gastrointestinal simulations, when β-glucan was added to a high-fat food model, the concentration of free fatty acids (FFAs) were remarkably decreased. An intestinal epithelial cell model demonstrated that addition of β-glucan can significantly reduce the translocation of triglycerides (TGs) and FFAs.

Production of Hydroxytyrosol by Coculture Engineering.

Hydroxytyrosol is a valuable plant-derived phenolic compound with excellent pharmacological activities for application in the food and health care industries. Microbial biosynthesis provides a promising approach for sustainable production of hydroxytyrosol via metabolic engineering. However, its efficient production is limited by the machinery and resources available in the commonly used individual microbial platform, for example, .

Structural characterization of a water-soluble and antimicrobial β-glucan secreted by Rhizobium pusense.

In this study, a bacterium with the ability to extracellularly produce a water-soluble polysaccharide (with high molecular mass of 743 kDa) was obtained from saline soils. This strain named as ZB01 was identified as Rhizobium punsense by 16S rRNA sequence analysis. The monomer composition and structure of extracellular polysaccharides were investigated by high-performance anion-exchange chromatography-pulsed amperometric detector, Fourier-transform infrared, methylation and nuclear magnetic resonance spectroscopy analysis.

Lactulose production from lactose isomerization by chemo-catalysts and enzymes: Current status and future perspectives.

Lactulose, a semisynthetic nondigestive disaccharide with versatile applications in the food and pharmaceutical industries, has received increasing interest due to its significant health-promoting effects. Currently, industrial lactulose production is exclusively carried out by chemical isomerization of lactose via the Lobry de Bruyn-Alberda van Ekenstein (LA) rearrangement, and much work has been directed toward improving the conversion efficiency in terms of lactulose yield and purity by using new chemo-catalysts and integrated catalytic-purification systems. Lactulose can also be produced by an enzymatic route offering a potentially greener alternative to chemo-catalysis with fewer side products.

Production of Hydroxytyrosol by Metabolic Engineering of .

Hydroxytyrosol is an olive-derived phenolic compound of increasing commercial interest due to its health-promoting properties. In this study, a high-yield hydroxytyrosol-producing cell factory was established via a comprehensive metabolic engineering scheme. First, biosynthetic pathway of hydroxytyrosol was constructed in yeast by gene screening and overexpression of different phenol hydroxylases, among which paHD (from ) displayed the best catalytic performance.

Radio frequency as an innovative method to produce low-fat French fries.

Background: A large amount of evidence shows that excessive fat intake can increase the risk of obesity, type 2 diabetes, non-alcoholic fatty liver disease, and cardiovascular disease. The main purpose of this study was to use radio frequency (RF) technology to prepare low-fat French fries.

Results: RF treatment for 10 min significantly decreased the force required to cut potatoes and inhibited the enzymatic browning of fresh-cut potatoes.

Biotechnological advances for improving natural pigment production: a state-of-the-art review.

In current years, natural pigments are facing a fast-growing global market due to the increase of people's awareness of health and the discovery of novel pharmacological effects of various natural pigments, e.g., carotenoids, flavonoids, and curcuminoids.

Key determinants of misdiagnosis of tracheobronchial tuberculosis among senile patients in contemporary clinical practice: A retrospective analysis.

Background: Tracheobronchial tuberculosis (TBTB) is a common subtype of pulmonary tuberculosis. Concomitant diseases often obscure the diagnosis of senile TBTB.

Aim: To characterize senile patients with TBTB and to identify the potential causes of misdiagnosis.

Effects of pulse electric field pretreatment on the frying quality and pore characteristics of potato chips.

The main purpose of this work was to investigate the effect of pulsed electric field (PEF) treatment on the oil absorption capacity of potato chips, evaluated via changes to microstructure and pore characteristics. Our results showed that as electric field strength increased from 0 kV/cm (no pretreatment) to 5 kV/cm, the oil content of potato chips decreased by up to 20.6%.

Screening of a Bacillus subtilis strain producing both nattokinase and milk-clotting enzyme and its application in fermented milk with thrombolytic activity.

Bacillus subtilis is a generally recognized as safe probiotic, which is used as a starter for natto fermentation. Natto is a functional food with antithrombus function due to nattokinase. Compared with natto, fermented milk is a more popular fermented food, which is commonly fermented by Lactobacillus bulgaricus and Streptococcus.

Active Delivery of CRISPR System Using Targetable or Controllable Nanocarriers.

Among programmable nuclease-based genome editing tools, the clustered regularly interspaced short palindromic repeats (CRISPR) system with accuracy and the convenient operation is most promising to be applied in gene therapy. The development of effective delivery carriers for the CRISPR system is the major premise to achieve practical applications. Although many nanocarrier-mediated deliveries have been reported to be safer and cheaper over the physical and viral delivery, the accumulation at disease sites or controllability with the spatial or temporal resolution are still desired on nanocarriers to reduce side effects and off-target from the CRISPR system.

Enhancement of the Isomerization Activity and Thermostability of Cellobiose 2-Epimerase from by Exchange of a Flexible Loop.

Cellobiose 2-epimerase (CE) offers a promising enzymatic approach to produce lactulose. However, its application is limited by the unsatisfactory isomerization activity and thermostability. Our study attempted to optimize the catalytic performances of CEs by flexible loop exchange, for which four mutants were constructed using CE (CE from ) as a template.

Prevention and Alleviation of Dextran Sulfate Sodium Salt-Induced Inflammatory Bowel Disease in Mice With -Fermented Milk Inhibition of the Inflammatory Responses and Regulation of the Intestinal Flora.

The pathogenesis of inflammatory bowel disease (IBD) might be related to the local inflammatory damage and the dysbacteriosis of intestinal flora. Probiotics can regulate the intestinal flora and ameliorate IBD. The probiotic strain JNFE0126 was used as the starter of fermented milk.

Structure and chain conformation characterization of arabinoglucan from by-product of peanut oil processing.

A neutral polysaccharide (NPP) from peanut sediment of aqueous extraction process was purified via anion-exchange and gel-filtration chromatography. The weight-average molecular weight and polydispersity index were 3.36 × 10 Da and 1.

Chitosan/casein based microparticles with a bilayer shell-core structure for oral delivery of nattokinase.

Nattokinase is a thrombolytic enzyme obtained from Japanese traditional food natto for prevention and cure of thrombosis-related cardiovascular diseases. However, the effectiveness of nattokinase through oral intake is limited, due to the loss of thrombolytic activity in the acidic gastric juice. In this study, we develop a functional oral delivery system of nattokinase, in which chitosan microparticles were used as the carrier core to load nattokinase via genipin crosslinking and then covered by a casein-based protective shell via transglutaminase (TG) crosslinking.