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.

The colonic mucosal barrier is an important component of the intestinal barrier, and its integrity is crucial for maintaining digestive tract homeostasis and normal metabolism in the body. This study aimed to elucidate the mechanisms by which malvidin-3-O-galactoside (M3G) might ameliorate colonic mucosal barrier function, from the perspective of physical barrier function and immune barrier function. Male C57BL/6J mice were given dextran sulfate sodium (DSS) to establish a mice model for colitis and then administrated with or without M3G for one week. The results showed that M3G supplementation significantly improved the disease activity index (DAI) score and colon tissue injury in mice with DSS-induced colitis. M3G improved the colonic physical barrier function by modulating the expression of mucin2 (MUC2), claudin-1, occludin, zona occludens 1 (ZO-1), and intestinal fatty acid binding protein (iFABP) in the colonic mucosa. Additionally, M3G also relieved the colonic immune barrier of mice by increasing the level of secretory immunoglobulin A (SIgA) in colon tissue and the percentages of CD4+T (CD3+CD4+) and CD8+T (CD3+CD8+) cells in colon lamina propria monocytes in mice. Furthermore, M3G down-regulated Notch signaling pathway-related proteins such as Notch1, notch intracellular domain (NICD), delta-like ligand 4 (DLL4), delta-like ligand 1 (DLL1), and hairy/enhancer of split 1 (Hes1) of colon tissue. The present results demonstrated that M3G can improve colonic mucosal barrier function by inhibiting the Notch signaling pathway.

Fresh walnuts (Juglans regia L.) are challenging to store due to their high water content and delicate green appearance. It has been reported that sodium nitroprusside (SNP, a nitric oxide donor) can promote stress tolerance. However, whether SNP affects the postharvest quality of fresh walnuts remains unknown. This research showed that appropriate SNP treatment contributed to walnut preservation; in particular, 0.5 mmol/L SNP treatment resulted in a better appearance and less decay (59.7%). Compared with the control, this treatment not only increased the levels of proteases related to fresh walnut disease (chitinase and β-1,3-glucanase) but also increased the overall antioxidant level and reduced oxidant damage. Moreover, respiratory metabolism and ethylene release were greatly suppressed (9.5%), and the overall sensory evaluation did not reveal any adverse effects associated with a lower acid or peroxide content. Thus, it was inferred that the optimal SNP dose activated disease-related enzymes, mediated the physiological metabolism rate, regulated the ROS-redox balance and therefore reduced decay and maintained the walnut quality. This is the first report of SNP (NO) application for the preservation of fresh walnuts and may provide information to facilitate practical application of this potential innovation.

Vibrational spectroscopy is a green, rapid, and affordable analytical tool for analysing the quality, safety, and origin of biological materials in agri-food sectors. Pre-processing spectral data is crucial to removing instrumental interferences and physical artifacts when developing a classification model. However, there has yet to be a consensus on which spectral pre-processing method, settings, and decision parameters to use to optimise pre-processing for different spectroscopy tools. Using an arbitrary criterion poses a risk of applying the wrong type or too severe pre-processing that removes valuable information or affects the model's performance for prediction studies. Matthew's Correlation Coefficient (MCC) - a statistic for parameterising classification performance, accounts for data set imbalance and improved decisions on model selection to express uncertainty on future predictions. Four vibrational spectroscopy instruments [near-infrared (NIR), hyperspectral (HSI), mid-infrared (FTIR), and Raman] were compared using different pre-processing methods to understand the performance using MCC to classify coffee from four countries (Indonesia, Ethiopia, Brazil and Rwanda). Key decision parameters were evaluated for the development of reliable classification models. The best pre-processing for NIR was extended multiplicative scatter correction with mean centering (MNCN), and for HSI, Savitzky-Golay (1st derivative, 15 points) with MNCN. NIR performed the best across all four instruments, with FTIR performing the worst. Raman showed potential for coffee origin classification using the right pre-processing. Pre-processing with weighted least squares, normalisation, and MNCN eliminated the fluorescence effect on Raman spectral data. These findings show the feasibility of using MCC for classification problems.

Alternaria alternata and Botrytis cinerea are among the primary fungal pathogens of fruits, causing black spot and gray mold disease, respectively. They cause serious losses in yield as well as affect fruit quality. Controlling fruit postharvest diseases largely relies on the use of chemical fungicides. However, the overuse of fungicides makes the produce unsafe due to their residual effects on the environment and human health. Therefore, significant advancements are necessary to investigate and find sustainable ways to prevent postharvest disease of fruits and minimize postharvest losses. This review summarizes the recent developments in the application of biological control and other sustainable approaches in managing fruit postharvest diseases, with an emphasis on A. alternata and B. cinerea, respectively. Furthermore, several action mechanisms, challenges, and prospects for the application of biological control agents (BCAs) are also discussed. Biological control application has been proven to successfully reduce postharvest disease of fruits caused by A. alternata and B. cinerea. In recent years, it has gradually changed from being primarily an independent field to a more crucial part of integrated pest management. Due to their characteristics that are safe, eco-friendly, and non-toxic, several BCAs have also been developed and commercialized. Therefore, biological control has the potential to be a promising approach to replace the use of chemical fungicides in controlling postharvest disease of fruits.

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.