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.

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.

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.

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 (CR), 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.

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 (CR), 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.

β-ionone has various biological activities, such as anti-inflammatory, antimicrobial, and anticancer effects. The pathogenesis of ulcerative colitis is correlated with immune dysfunction, intestinal barrier damage, and gut microbiota imbalance. However, whether β-ionone has preventive efficacy against ulcerative colitis is unknown. This study investigated the effect of β-ionone on dextran sulfate sodium-induced ulcerative colitis and the underlying molecular mechanisms involved. The ulcerative colitis mouse model was induced by 1.5% dextran sulfate sodium for 10 d. Meanwhile, 200 mg/kg β-ionone was administrated to the mice. Body weight, colon length, colon tissue pathology, colon tissue inflammatory cytokines, colonic oxidative stress, and barrier function were assessed. The composition and structure of gut microbiota were profiled using 16S rRNA sequencing. The results showed that β-ionone supplementation effectively prevented ulcerative colitis by ameliorating colonic tissue damage, reducing inflammatory phenomena, and protecting the colonic epithelial mucosal barrier. β-ionone also protected mice from dextran sulfate sodium-induced gut microbiota disturbance by modifying the overall structure and function of the gut microbiota community and increasing the relative abundance of beneficial gut microbiota. The Spearman correlation analysis revealed that the changes in abundance of the gut microbiota were correlated with ulcerative colitis-related indicators. Overall, this study demonstrated that β-ionone has a preventive effect on ulcerative colitis in mice, and the underlying mechanism may be associated with the protection of the gut barrier and regulation of the gut microbiota. These results are conducive to promoting clinical trials and product development of β-ionone for the prevention and treatment of ulcerative colitis.

β-ionone has various biological activities, such as anti-inflammatory, antimicrobial, and anticancer effects. The pathogenesis of ulcerative colitis is correlated with immune dysfunction, intestinal barrier damage, and gut microbiota imbalance. However, whether β-ionone has preventive efficacy against ulcerative colitis is unknown. This study investigated the effect of β-ionone on dextran sulfate sodium-induced ulcerative colitis and the underlying molecular mechanisms involved. The ulcerative colitis mouse model was induced by 1.5% dextran sulfate sodium for 10 d. Meanwhile, 200 mg/kg β-ionone was administrated to the mice. Body weight, colon length, colon tissue pathology, colon tissue inflammatory cytokines, colonic oxidative stress, and barrier function were assessed. The composition and structure of gut microbiota were profiled using 16S rRNA sequencing. The results showed that β-ionone supplementation effectively prevented ulcerative colitis by ameliorating colonic tissue damage, reducing inflammatory phenomena, and protecting the colonic epithelial mucosal barrier. β-ionone also protected mice from dextran sulfate sodium-induced gut microbiota disturbance by modifying the overall structure and function of the gut microbiota community and increasing the relative abundance of beneficial gut microbiota. The Spearman correlation analysis revealed that the changes in abundance of the gut microbiota were correlated with ulcerative colitis-related indicators. Overall, this study demonstrated that β-ionone has a preventive effect on ulcerative colitis in mice, and the underlying mechanism may be associated with the protection of the gut barrier and regulation of the gut microbiota. These results are conducive to promoting clinical trials and product development of β-ionone for the prevention and treatment of ulcerative colitis.

Baijiu Daqu, a traditional component in the Baijiu brewing process, serves as both a 'saccharifying fermenting agent' and an 'aroma-producing catalyst', embodying a rich historical legacy. Daqu offers a diverse microorganism environment that is crucial for the fermentation of Baijiu. The distinctive flavor profile, a key attribute of Baijiu, is intricately linked to the microflora present in Daqu. To date, research on Daqu has primarily concentrated on the diversity of microbial communities, microbial interactions, flavor characteristics, and biochemical properties. The functional enzyme system in Daqu serves as a crucial link connecting the flavor of Baijiu with the microbial community of Daqu. However, reviews that particularly focus on the role of enzymes in determining the quality of Daqu have not yet been reported. Thus, here the types and production processes of Daqu are initially summarized. Then, the pathways involved in the production of the major flavor substances in Daqu are elucidated, as well as the role and contribution of different functional enzymes in the formation of Daqu flavor. Finally, the current technologies for improving Daqu flavor through microbial inoculation aree discussed, including the advantages, shortcomings, and bottlenecks of microbial inoculation. The findings gained in this study provide valuable information for the efficient production of high-quality Daqu for the brewing of Baijiu.

Baijiu Daqu, a traditional component in the Baijiu brewing process, serves as both a 'saccharifying fermenting agent' and an 'aroma-producing catalyst', embodying a rich historical legacy. Daqu offers a diverse microorganism environment that is crucial for the fermentation of Baijiu. The distinctive flavor profile, a key attribute of Baijiu, is intricately linked to the microflora present in Daqu. To date, research on Daqu has primarily concentrated on the diversity of microbial communities, microbial interactions, flavor characteristics, and biochemical properties. The functional enzyme system in Daqu serves as a crucial link connecting the flavor of Baijiu with the microbial community of Daqu. However, reviews that particularly focus on the role of enzymes in determining the quality of Daqu have not yet been reported. Thus, here the types and production processes of Daqu are initially summarized. Then, the pathways involved in the production of the major flavor substances in Daqu are elucidated, as well as the role and contribution of different functional enzymes in the formation of Daqu flavor. Finally, the current technologies for improving Daqu flavor through microbial inoculation aree discussed, including the advantages, shortcomings, and bottlenecks of microbial inoculation. The findings gained in this study provide valuable information for the efficient production of high-quality Daqu for the brewing of Baijiu.

Serum albumin can bind with a diverse range of small molecules. It could therefore serve a protective or carrier function, and effectively address the issue of anthocyanins' susceptibility to decomposition. The anisotropic effect of the magnetic field (MF) can influence their interaction, thereby playing a distinct role in molecular bonding. In this study, bovine serum albumin (BSA) and cyanidin-3-O-glucoside (C3G) were used as raw materials. The mechanism underlying the formation of BSA-C3G complexes induced by static magnetic field (SMF) was investigated through analyses of secondary structure, functional groups, dipole moment, crystal cell dimensions, and microstructural characteristics. BSA and C3G were treated with 50, 100, 150, and 200 mT, respectively. As the magnetic intensity increased, the secondary structure of the complex changed, the α-spiral content, β-corner content, and irregular curl content decreased, while, the β-folding content increased. The average grain size of the BSA-C3G composite was observed to decrease. Furthermore, alterations in the crystal cell dimensions of the BSA-C3G complex were noted, accompanied by a tendency for the microstructure to become more flattened. This study offers valuable insights into the influence of SMF on the assembly behavior and structural characteristics of proteins and anthocyanins.

Serum albumin can bind with a diverse range of small molecules. It could therefore serve a protective or carrier function, and effectively address the issue of anthocyanins' susceptibility to decomposition. The anisotropic effect of the magnetic field (MF) can influence their interaction, thereby playing a distinct role in molecular bonding. In this study, bovine serum albumin (BSA) and cyanidin-3-O-glucoside (C3G) were used as raw materials. The mechanism underlying the formation of BSA-C3G complexes induced by static magnetic field (SMF) was investigated through analyses of secondary structure, functional groups, dipole moment, crystal cell dimensions, and microstructural characteristics. BSA and C3G were treated with 50, 100, 150, and 200 mT, respectively. As the magnetic intensity increased, the secondary structure of the complex changed, the α-spiral content, β-corner content, and irregular curl content decreased, while, the β-folding content increased. The average grain size of the BSA-C3G composite was observed to decrease. Furthermore, alterations in the crystal cell dimensions of the BSA-C3G complex were noted, accompanied by a tendency for the microstructure to become more flattened. This study offers valuable insights into the influence of SMF on the assembly behavior and structural characteristics of proteins and anthocyanins.

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.

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.

The loss of pericarp greenness, wrinkling of the pericarp, and alteration of aroma are indicators of the ripening and senescence of lemons. In this study, lemons were soaked in 100 mg∙L-1 of gibberellin (GA) solutions for 5 min and stored at 14°C for 36 d under three relative humidity (RH) levels of 30%, 60%, and 90%, respectively. The changes in visual appearance, pigment metabolism, pericarpic microstructure, and volatile compounds of lemons during storage were evaluated. The results showed that GA pretreatment inhibited the color transformation from green to yellow of the flavedo and restrained fruit senescence. In addition, RH 90% effectively maintained the structural integrity of the oil gland, waxes, and stomata in the flavedo. GAs + RH 90% treatment maintained the fruit color index (L*, a*, b*, a*/b*, H°, C*) by inhibiting chlorophyll degradation and regulating carotenoid biosynthesis. Green lemons treated with GAs + RH 90% also showed reduced epidermal wrinkling, well-preserved cuticle, and stomatal structure, with a smooth and intact wax layer on the lemon pericarp. In addition, GAs + RH 90% treatment maintained the content of volatile aroma compounds, especially terpene. GAs + RH 90% had a great advantage in maintaining visual quality, delaying the deformation of tissue microstructure, preserving nutritional quality, and improving aroma. Thus, this treatment is potentially applicable for maintaining the storage quality of green lemons and extending their shelf life.

The loss of pericarp greenness, wrinkling of the pericarp, and alteration of aroma are indicators of the ripening and senescence of lemons. In this study, lemons were soaked in 100 mg∙L-1 of gibberellin (GA) solutions for 5 min and stored at 14°C for 36 d under three relative humidity (RH) levels of 30%, 60%, and 90%, respectively. The changes in visual appearance, pigment metabolism, pericarpic microstructure, and volatile compounds of lemons during storage were evaluated. The results showed that GA pretreatment inhibited the color transformation from green to yellow of the flavedo and restrained fruit senescence. In addition, RH 90% effectively maintained the structural integrity of the oil gland, waxes, and stomata in the flavedo. GAs + RH 90% treatment maintained the fruit color index (L*, a*, b*, a*/b*, H°, C*) by inhibiting chlorophyll degradation and regulating carotenoid biosynthesis. Green lemons treated with GAs + RH 90% also showed reduced epidermal wrinkling, well-preserved cuticle, and stomatal structure, with a smooth and intact wax layer on the lemon pericarp. In addition, GAs + RH 90% treatment maintained the content of volatile aroma compounds, especially terpene. GAs + RH 90% had a great advantage in maintaining visual quality, delaying the deformation of tissue microstructure, preserving nutritional quality, and improving aroma. Thus, this treatment is potentially applicable for maintaining the storage quality of green lemons and extending their shelf life.

Chilling injury (CI) is a highly common physiological disorder in pomegranates during cold storage. Although several approaches have been investigated to mitigate the CI symptoms among some pomegranate cultivars, the fundamental and crucial environmental factor — the precise storage temperature for the 'Mengzi' cultivation remains unknown. This research evaluated the impact of storage temperatures of 0, 1, 2, 3, and 4 °C on the post-harvest quality of pomegranates. Results indicated that pomegranates stored at 2 °C exhibited the slightest color change and browning index. After storage of 130 d, pomegranates stored at 2 °C exhibited the lower CI index (82.79% reduction) and the lowest decay incidence (24.68% reduction) compared to those stored at 0 °C. The respiratory rate of pomegranates (2 °C) was also evidently suppressed (16.60%), along with a reduction in weight loss (3.46%). Furthermore, pomegranates stored at 2 °C exhibited the lowest activities of polyphenol oxidase (PPO) and peroxidase (POD), accompanied by the highest total phenolic content, which contributed to a reduction in malondialdehyde (MDA) accumulation. Relatively higher concentrations of soluble solids and titratable acid, as well as a higher sensory evaluation, were found in pomegranates stored at 2 °C. Consequently, it was inferred that the optimal temperature maintained cell membrane integrity modulated normal respiratory metabolism, and oxidative balance, and therefore alleviated CI and deterioration. This report can provide the guiding significance for the long-term storage of 'Mengzi' pomegranates under the condition of precise temperature control in phase temperature storage.

Chilling injury (CI) is a highly common physiological disorder in pomegranates during cold storage. Although several approaches have been investigated to mitigate the CI symptoms among some pomegranate cultivars, the fundamental and crucial environmental factor — the precise storage temperature for the 'Mengzi' cultivation remains unknown. This research evaluated the impact of storage temperatures of 0, 1, 2, 3, and 4 °C on the post-harvest quality of pomegranates. Results indicated that pomegranates stored at 2 °C exhibited the slightest color change and browning index. After storage of 130 d, pomegranates stored at 2 °C exhibited the lower CI index (82.79% reduction) and the lowest decay incidence (24.68% reduction) compared to those stored at 0 °C. The respiratory rate of pomegranates (2 °C) was also evidently suppressed (16.60%), along with a reduction in weight loss (3.46%). Furthermore, pomegranates stored at 2 °C exhibited the lowest activities of polyphenol oxidase (PPO) and peroxidase (POD), accompanied by the highest total phenolic content, which contributed to a reduction in malondialdehyde (MDA) accumulation. Relatively higher concentrations of soluble solids and titratable acid, as well as a higher sensory evaluation, were found in pomegranates stored at 2 °C. Consequently, it was inferred that the optimal temperature maintained cell membrane integrity modulated normal respiratory metabolism, and oxidative balance, and therefore alleviated CI and deterioration. This report can provide the guiding significance for the long-term storage of 'Mengzi' pomegranates under the condition of precise temperature control in phase temperature storage.