Saccharomyces cerevisiae is the earliest domesticated fungus, researched deeply and widely used fungus. When used in food fermentation, Saccharomyces cerevisiae has an important influence on the quality, flavor, and aroma of products. Future developments will focus on enhancing flavor diversity, increasing production efficiency, sustainability, and product consistency, as well as improving the fermentation characteristics by using advanced technologies. Saccharomyces cerevisiae is an ideal substrate for synthetic biology research, usually used in the production of lactic acid, terpenes, steroids, vaccines, etc., which helps to reduce production cost, shorten the production cycle, improve production capacity, and has a very broad application prospect. In addition, in the field of environmental protection, biofuel ethanol is one of the promising and popular fuels with potential for energy and environmental security. However, there are major challenges for Saccharomyces cerevisiae that use lignocellulosic biomass as feedstock to produce biofuel ethanol.

The peel of pitaya fruit is a promising source of pectin, and non- or low-methylesterified pectin has multiple bioactivities and application scenarios. In this study, non-methylated pectin was prepared from pitaya peel and the structure was characterized. Single factor experiment and response surface methodology were conducted to optimize the procedure of ultrasonic-assisted extraction for pectin. Under the optimal conditions (solid-liquid ratio of 1:40 g·mL−1, extraction temperature at 56 °C, extraction time of 25 min and ultrasonic power of 200 W), the pectin yield was up to 9.93% ± 0.97%. Degree of methylesterification and FTIR analysis confirmed that the extracted pectin was almost non-methylesterified. The pectin possessed less linear homogalacturonan (HG) but more rhamnogalacturonan (RG) regions according to the molar ratios of monosaccharides. Meanwhile, the molecular weight of the pectin was 33.52 kDa and the crystalline index was only 0.60%. Furthermore, the nanoscale structure observed by atomic force microscopy showed that the pectin was rich in highly branched polymers. Generally, pitaya peel pectin extracted by ultrasonic-assisted extraction showed a wide range of potential use as a non-or low- methylesterified pectic substance to reach the efficient utilization of fruit waste.

Carboxypeptidase A(CPA) has a great potential application in the food and pharmaceutical industry due to its capability to hydrolyze ochratoxin A(OTA) and remove the bitterness of peptide. However, CPA is a mesophilic enzyme that cannot adequately exert its catalytic activity at elevated temperatures, which seriously restricts its industrial application. In this study, the rational design of disulfide bonds was introduced to improve the thermostability of CPA. The highly flexible regions of CPA were predicted through the HotSpot Wizard program and molecular dynamics (MD) simulations. Then, DbD and MODIP online servers were conducted to predict potential residue pairs for introducing disulfide bonds in CPA. After the conservativeness analysis of the PSSM matrix and the structural analysis of the MD simulation, two mutants with potentially enhanced thermostability were screened. Results showed that these mutants D93C/F96C and K153C/S251C compared to the wild-type(WT) exhibited increase by 10 and 10 °C in Topt, 3.4 and 2.7 min in t1/2 at 65 °C, in addition to rise of 8.5 and 11.4 °C in T5015, respectively. Furthermore, the molecular mechanism responsible for thermostability was investigated from the perspective of advanced structure and molecular interactions. The enhanced thermostability of both mutants was not only associated with the more stable secondary structure and the introduction of disulfide bonds but also related to the changes in hydrogen bonds and the redistribution of surface charges in mutant regions. This study showed for the first time that the rational design of disulfide bonds is an effective strategy to enhance the thermostability of CPA, providing in this way a broader industrial application.

Lily bulbs are valued for their health benefits, and drying is a common method for their preservation. This study employed untargeted metabolomics using UHPLC-QTOF-MS to analyze the phytochemical profiles of lily bulbs dried by hot air (HD), microwave (MD), and vacuum freeze (FD) methods. In terms of appearance, FD samples exhibited minimal browning and wrinkling, while HD bulbs showed the most severe changes. Nineteen potential markers were identified, with HD samples showing higher levels of bitter amino acids, peptides, and N-fructosyl phenylalanine. The markers of FD samples were glutamine, coumarin, and p-coumaric acid. Notably, eleutheroside E was detected in lily bulbs for the first time and confirmed as an MD marker, with levels 1.51-fold and 6.19-fold higher than in FD and HD samples, respectively. MD method shows promise for enriching bioactive compounds in dried lily bulbs.

Chlorophyll (Chl), the most widely distributed natural pigment in nature, is limited in use due to its poor stability. This study refers to the aggregation structure of Chl and carotene (Car) in natural photosynthetic systems, hoping to improve the photostability of Chl by constructing Chl/Car aggregates. The stability protection effect of Car on Chl was explored by designing different ratios of Chl and Car aggregation systems. The configuration of Chl/Car aggregates was optimized through ab initio molecular dynamics, and the aggregation mechanism of the aggregates and the photoprotection mechanism of Chl by Car were elucidated through quantum chemical calculations and wave function analysis. Chl/Car had a 27.22% higher Chl retention rate than free Chl after 7 d of illumination, with a Chl to Car ratio of 1.66:1. A configuration of the Chl/Car aggregates which Car's conjugated olefin chain interacts extensively with the porphyrin ring and bent phytyl chain of Chl made them more stable. The photoprotective mechanism of Car on Chl in the Chl/Car aggregates is elucidated. Car's conjugated polyene chain provides HOMO orbitals to the Chl/Car aggregates. It demonstrated that Car supplies electrons in the low-lying excited states S2 and S4, indicating it is more susceptible to damage, protecting Chl. This research will promote the development of natural color formulas and ensure the health of consumers.

Curcumin compounds are important bioactive compounds in ginger, yet their analysis is limited by their low concentrations. In the current research, a highly sensitive and reliable approach for simultaneous quantitative detection of three curcumin compounds in ginger samples was established using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The extraction solvent, volume of extraction solvent, sonication time, and oscillation time were optimized by a single factor experiment. The method validation results showed that the regression coefficients were higher than 0.9990, and the linearity was satisfactory. Matrix effects were negligible with the values of 94.6%–98.8%. The recovery at three spiking levels was between 81.7% and 100.0%, and the precision was less than 5.4%. The approach could be used to determine the curcumin components in ginger samples since the results demonstrate that it is easy to use, practicable, repeatable, and accurate.

The dissolution patterns of different teas determine the sensory quality and health attributes of the tea infusion. In this study, the chemical profiles of two typical selenium-enriched green teas, Xiazhou Bifeng (Se-BF), Enshi Yulu (Se-YL), and their corresponding regular green teas (BF and YL) were determined. Under the application of selenium fertilizer, the contents of caffeine, polyphenols, and gallic acid decreased, while the contents of theaflavins, theabrownins, and chlorophylls increased. The selenium content in BF and YL is 0.05−0.16 mg/kg and 0.33−0.43 mg/kg respectively, while after the application of exogenous selenium, the selenium content in Se-BF and Se-YL reached 1.28 to 2.17 mg/kg and 0.37−2.23 mg/kg respectively. The dissolution patterns of Se-BF and Se-YL were investigated under different brewing conditions (temperature and duration), and the main components of Se-YL were more easily dissolved out than Se-BF, which might be attributed to the steaming process of Se-YL. Based on the sensory evaluation of tea infusion, 100 °C and 5 min were the optimal brewing conditions. Based on a daily tea consumption model, the increased brewing time reduced the content of dissolved components in tea infusions, along with the decreased in vitro antioxidant and hypoglycemic activities. Collectively, Se-YL demonstrated superior sensory and nutritional attributes compared to Se-BF. This study explored the influence of brewing conditions on the dissolution patterns and in vitro bioactivities of selenium-enriched green teas, providing guidance for scientific tea brewing and consumption.

Gut microbiota-associated metabolites can be synthesized endogenously or derived from dietary nutrients and host compounds. Among them, alkaloids, terpenes, and flavones originating from edible and medicinal foods have attracted remarkable interest recently and play crucial roles in metabolic diseases. The efficacy of these metabolites is susceptible to dietary intervention, especially after food processing. Therefore, this review comprehensively summarizes the different sources of common gut microbial metabolites, including microbial self-synthesis, biodegradation of exogenous substances (mainly dietary nutrients), and participation in host metabolism. In addition, the latest studies on novel metabolites such as alkaloids, terpenoids, and flavonoids are discussed, and their action mechanisms on metabolic diseases are elaborated. How food processing impacts dietary nutrients and their metabolites is carefully examined, as well as their effects on disease modification. These insights could contribute to a deeper understanding of the mechanisms by which diet efficacy helps prevent metabolic diseases, particularly through gut microbial metabolites.

Designing a wound dressing that offers excellent antibacterial properties while providing dual pH/glucose responsiveness for diabetic wound healing remains a considerable challenge. Herein, a 3D cross-linked native protein hydrogel was constructed through a Schiff base reaction based on -NH2 in paramyosin (PM) and -CHO in oxidized dextran (ODA) under mild conditions. Within the hydrogel, both amikacin and glucose oxidase were encapsulated during gelation. The resulting hydrogel exhibited favorable rheological properties, featuring self-healing, antibacterial activity, tissue adhesiveness, and excellent biocompatibility. Notably, the hydrogel demonstrated excellent pH/glucose dual-responsive properties. In infected wounds, the Schiff base bonds dissociated due to low pH, while in uninfected wounds with high blood glucose levels, the encapsulated glucose oxidase was functional, which also lowered the local pH level and dissociated the Schiff base bonds. Furthermore, the hydrogel quickly achieved pH/glucose dual responsiveness, leading to increased amikacin release to reduce bacterial invasion, alleviate oxidative stress, promote re-epithelialization and collagen deposition, and eventually accelerate diabetic wound healing. Collectively, the constructed hydrogel offers brand-new viewpoints on glucose-responsive biomaterials for diabetic wound therapy.

In this study, microfluidization was explored to inactivate autolytic spoilage enzymes (polyphenol oxidase, PPO, and peroxidase, POD) that significantly impact the nutritional and sensory qualities of tender coconut water (TCW). TCW was treated at three different pressure levels (70, 140, and 210 MPa) and five different number of passes/cycles (3, 5, 7, 9, and 11). The highest percentage reduction was obtained in the case of PPO (~61% in the 11th pass, at 210 MPa), while for POD, ~45% reduction was achieved in the 9th pass, at 70 MPa. The impact of different treatment conditions on the physicochemical properties of TCW, such as color, turbidity, total soluble solids (TSS), pH, titratable acidity, total phenolic content (TPC), and protein content was assessed. The pH and TSS remained unaffected; whereas, turbidity showed an increase with treatment intensity from 2.59% ± 0.14% (untreated) to 8.62% ± 0.39% (30,000 psi, 11 passes), and the highest color difference was observed for this sample (ΔE = 4.61 ± 0.018). Furthermore, TPC and antioxidant activity showed minimal changes upon treatment. Overall, the findings of this research provide new insights into the application of microfluidization for the processing of thermally sensitive products such as TCW, extending their shelf life without any additives and providing a clean label solution.