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.

In this work, the gastrointestinal digestive outcome of Tremella fuciformis polysaccharide (TFP) was examined using in vitro simulated experiments, together with its effect on the intestinal microbiota. TFP did not significantly alter during the stage of oral digestion, according to an in vitro digestion investigation. Nevertheless, glycosidic connections of TFP were broken throughout the intestinal and stomach digesting phases, which resulted in the dissociation of macromolecular aggregates, a marked rise in decreasing sugar content (C _R), as well as a drop in molecular weight (Mw). Additionally, microbial community analysis following fecal fermentation in vitro indicated that TFP might control the alpha and beta diversity of gut microbiota and change the genus- and phylum-level community composition. It increased the abundance of beneficial bacteria including Megasphaera, Phascolarctobacterium, and Bacteroides, and suppressed the growth of harmful bacteria like Escherichia-shigella and Fusobacterium, thus contributing to maintaining gut homeostasis. These results suggested that TFP could have a positive impact on health through enhancing the gut microbiota environment, giving a theoretical basis for its use as a prebiotic.

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 T _opt , 3.4 and 2.7 min in t _1/2 at 65 °C, in addition to rise of 8.5 and 11.4 °C in T ₅₀ ¹⁵ , 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.

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.

Changes in the quality of blue honeysuckle fruit following exposure to air or controlled atmospheres (CA1: 20% O ₂ and 20% CO ₂; CA2: 5% O ₂ and 20% CO ₂; CA3: 5% O ₂ and 10% CO ₂) were investigated. The 'Lanjingling’ blue honeysuckle was stored at a temperature of −1 °C for a duration of 28 d. An elevated concentration of CO ₂ led to a reduction in fruit weight loss, ethanol content, and respiration rate, while simultaneously increasing the epicuticular wax coverage index, firmness, TSS, ascorbic acid, polyphenols, and antioxidant capacity. Notably, treatment with high levels of carbon dioxide (20% CO ₂) led to an approximately 150% increase in total anthocyanin content compared to control conditions. Additionally, it was observed that reducing the oxygen content from 20% to 5% had a detrimental effect on the antioxidant capacity of blue honeysuckle during storage. Specifically, there were decreases of 10.4%, 16.8%, and 6.7% in DPPH, ABTS, and FRAP, respectively. The respiration rate is increased by treatment with 5% O ₂ and 5% CO ₂, which may result in accelerated senescence of blue honeysuckle. After 28 d, the treatment resulted in a respiration rate that was 1.49 times higher than the control. Hence, it can be deduced that maintaining a controlled atmosphere containing 20% O ₂ and 20% CO ₂ can be deemed an effective method of blue honeysuckle for prolonging storage life and safeguarding its bioactive components.

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.

Studying the metabolic patterns underlying the key quality traits during the growth and development of melon is very important for the quality improvement and breeding of melon fruit. In this study, we employed transcriptomics and metabolomics to analyze the primary metabolic changes occurring in melon ('Xizhoumi 25') across five growth and development stages. We identified a total of 666 metabolites and their co-expressed genes, which were categorized into five different metabolic and gene modules. Through the analysis of these modules, the main metabolic pathways during the growth and development of melon were demonstrated from a global perspective. We also discussed the contribution of sucrose accumulation, the TCA cycle, and amino acid metabolism to the quality and flavor of melon. Enzymes related to amino acid metabolism were proposed, including Amine oxidase (AOC), aldehyde dehydrogenase (ALDH), tryptophan synthase (TRPB), etc. These results and data can provide new insights for further study on the metabolic regulation of melon quality and improve fruit quality.

As a superfruit, wolfberry has extremely high nutritional value, and how to enhance the accessibility of its nutrients is the core of current research. This study focused on exploring the kinetic model of Lactobacillus plantarum CCFM1050 fermentation of wolfberry and the potential alterations of antioxidant activity and volatile flavor compounds induced by lactic acid fermentation. we monitored cell counts, product formation, and substrate changes over a 72-h period of wolfberry fermentation. A kinetic model was developed to illustrate cell growth, substrate consumption, and product accumulation during wolfberry pulp fermentation. Phenolic substance analysis revealed a significant increase in total phenol and flavonoid content in wolfberry pulp during fermentation, reaching 1.16 and 1.15 times, respectively, compared to pre-fermentation levels. The elevated levels of phenolic substances led to a substantial increase in DPPH and ABTS free radical scavenging rates in fermented wolfberry pulp, reaching 67.16% and 32.10%, respectively. Volatile components of samples were analyzed using the HS-GC-IMS method, and fingerprints of wolfberry pulp before and after fermentation were established. A total of 51 compounds were identified, including 12 alcohols, seven aldehydes, two acids, eight esters, and 12 ketones, contributing to an enhanced flavor profile in the fermented wolfberry pulp. This study is helpful for understanding the kinetic changes in the lactic acid fermentation of wolfberry, the changes of antioxidant active substances and VOCs, and provides guidance for the industrial processing of wolfberry.

Cork taint has devastating effects on the aroma and quality of the wine, which can cause an annual loss of may be up to more than one billion dollars. There are many causes of cork taint, but 2,4,6-trichloroanisole (2,4,6-TCA) is a major contributor, giving the wine a wet-moldy smell. This study provided a comprehensive overview of the occurrence, detection, and control/remediation of 2,4,6-TCA. The occurrence and formation mechanisms of 2,4,6-TCA mainly include microbial O-methylation of chlorophenols and chlorination of anisole. The source of 2,4,6-TCA in wine is the cork or other woodworks, but it is also possible to contaminate wine from the environment. Due to the extremely low odor threshold concentration of 2,4,6-TCA, the effective sample pre-enrichment for instrument identification and quantification is more important. The control/remediation strategies of 2,4,6-TCA mainly include eliminating 2,4,6-TCA in cork and removing 2,4,6-TCA from wine by adsorption. Finally, the challenges and possible future research directions in this research field were discussed and proposed.

The impact of microwave-assisted thermal sterilization (MATS) on three natural pigments and their storage stability in vegetable purees was investigated. We selected carrot puree for beta carotene, red cabbage puree for anthocyanins, and red beetroot puree for betalains. The purees were packaged in multilayer flexible pouches of AlOx-coated PET (12 μm)//AlOx-coated PET (12 μm)//AlOx-coated PET (12 μm)//ONy (15 μm)//CPP (70 μm), then processed with the MATS system to F _o = 6 to 11 min. After MATS treatment, the pouches were stored for 6 months at a storage temperature of 37.8 °C. The MATS treatment had a significant impact ( p < 0.05) on the instrumental colors of three purees, with the total color difference (Δ E) ranging between 6.0 and 10.5. Similarly, the concentration of betalains experienced degradation by 20%−29% after the MATS treatment, while beta-carotene concentration showed a high retention. In addition, the pH of the purees declined considerably ( p < 0.05) after the MATS treatment. Over the 6 months of storage at 37.8 °C, the PET-metal oxide pouches maintained the moisture content in all the purees, as the weight loss was only 0.43%−0.45%. The pigments in the MATS-processed purees had different levels of stability; Δ E values varied between 4.23 and 12.3. Beta-carotene was the most stable pigment, followed by betalains and anthocyanins. The degradation of both betalains and anthocyanins during storage was explained by first and fractional conversion models. MATS processing and packages with high gas barriers can therefore be used to preserve selected vegetable purees rich in natural pigments.

Soy milk, rich in vitamin D and calcium, is a common alternative to dairy milk. However, its distinct 'beany off-flavor' has limited its acceptance, particularly in Western countries. A new technique employing preformed 'empty' V-type starch has been introduced to scavenge this off-flavor, aiming to promote soy milk consumption. The purpose of this study was to identify predictors of consumers' purchase intention of 'empty' V-type starch deodorized soy milk, particularly among college students. In this cross-sectional study, 105 college students were surveyed by a validated survey instrument that measures their perceptions of sensory quality, healthiness, price, environmental friendliness, food safety, and purchase intention of a novel product – 'empty' V-type starch deodorized soy milk. Additionally, demographic data were gathered to understand any correlations between these factors and the students' willingness-to-purchase of the deodorized soy milk. From the results, more than 80% of the participants expressed a positive attitude toward the 'empty' V-type starch-deodorized soy milk. The two dominant drivers behind their purchasing decision were Sensory Quality and Environmental Concern. Accordingly, it is crucial to highlight the improved sensory profile and the environmental friendliness of this soy milk product in order to achieve marketing success.

Investigating the influences of different sterilization methods on overall juice quality is essential for the production of high-quality juice. The effects of ultra-high temperature instantaneous sterilization (UHT), thermosonication (TS), high hydrostatic pressure sterilization (HHP), and irradiation sterilization (IS) on the physicochemical properties, functional components, and color of Aronia melanocarpa juice (AMJ) were investigated. In addition, anthocyanin target metabolomics were used to explore the influences of different sterilization methods on the AMJ anthocyanin profile. All sterilization treatments effectively ensured the microbial safety of AMJ, and the AMJ viscosity was noticeably declined after sterilization ( p < 0.05). Except for HHP, the other treatments aggravated AMJ browning ( p < 0.05). Both TS and HHP treatments significantly enhanced or preserved the total polyphenols, flavonoids, and anthocyanins in AMJ and retained the original juice color, whereas UHT and IS treatments were not conducive to maintaining these characteristics. TS treatment significantly increased cyanidin-3-O-galactoside (C-3-O-gal) and cyanidin-3-O-arabinoside (C-3-O-ara) contents in AMJ by 7.98% and 5.90%, while IS resulted in a significant decrease of 15.74% and 10.46% ( p < 0.05). C-3-O-gal and C-3-O-ara were the major reasons for the significant upregulation and downregulation of the total monomeric anthocyanins contents (TMAC) in the AMJ after TS and IS treatment, respectively. Malvidin-3-O-glucoside (M-3-O-glu), Cyanidin-3-O-(6-O-malonyl- β-D-glucoside) and Kaempferol-3-O-rutinoside (K-3-O-rut) might be markers of differential metabolites produced by the TS, HHP, and IS treatments, respectively. Correlation analysis indicated that Cyanidin-3-O-xyloside (C-3-O-xyl), C-3-O-ara, and Pelargonidin-3-O-arabinoside (P-3-O-ara) might be the principal contributed to the antioxidant capacity of AMJ. The research results are anticipated to supply technical reference for AMJ processing.

Microalgae are increasingly regarded as a sustainable source of novel food and functional products due to their nutritional composition. This study aimed to conduct an in-depth analysis of the chemical, microstructural and rheological, and volatile-flavour related properties of Arthrospira, Isochrysis, Nannochloropsis, and Tetraselmis species. Chemometric data analysis was employed to integrate the multivariate data, investigate the classification among the four species, and identify discriminating and distinct features. Arthrospira is high in protein content, and Nannochloropsis is lipid-rich with dominantly polyunsaturated fatty acids. Isochrysis is rich in carotenoids and total phenolics, while Tetraselmis is high in carbohydrates. Key discriminant volatile markers encompass aldehydes, terpenes, and hydrocarbons for Arthrospira; ketones and alcohols for Nannochloropsis; aldehydes, ketones, and sulfur-containing compounds for Tetraselmis; and furans and aldehydes for Isochrysis. Moreover, Arthrospira and Isochrysis demonstrate elevated viscosity and notable thickening potential. In summary, the different microalgal biomass studied in this study showcase unique compositional, rheological, and volatile properties, highlighting their potential as functional ingredients for diverse applications in the food and pharmaceutical industries.

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.

Arecoline, the principal active alkaloid in the areca nut, is known for its ability to induce euphoric sensations. Since ancient times, arecoline has garnered attention for its therapeutic potential in addressing psychiatric disorders and alleviating gastrointestinal ailments. However, in 2020, the International Agency for Research on Cancer has classified arecoline as 'probably carcinogenic to humans' (Group 2B carcinogen), supported by compelling mechanistic evidence. The mechanism of action of arecoline has been extensively studied, but the results of these studies are scattered and lack systematic integration and generalization. In this paper, we have systematically summarized the mechanism of arecoline within the oral cavity, central nervous system, cardiovascular system, and digestion system, in terms of both health functions and toxic effects. In addition, we found some concentration-effect relationship between arecoline in the central nervous system and digestive system, i.e., low doses are beneficial and high doses are harmful. By summarizing the mechanisms of arecoline, this review is poised to provide in-depth and valuable insights into the clinical practice and targeted therapy of arecoline in the future.