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.

An innovative chemometric method was developed to exploit visible and near-infrared (Vis-NIR) spectroscopy to guide food formulation to reach the anticipated and constant quality of final products. First, a total of 671 spectral variables related to the puree quality characteristics were identified by spectral variable selection methods. Second, the concentration profiles from multivariate curve resolution-alternative least squares (MCR-ALS) made it possible to reconstruct the identified spectral variables of formulated purees. Partial least square based on the reconstructed Vis-NIR spectral variables was evidenced to predict the final puree quality, such as a* values (RPD = 3.30), total sugars (RPD = 2.64), titratable acidity (RPD = 2.55) and malic acid (RPD = 2.67), based only on the spectral data of composed puree cultivars. These results open the possibility of controlling puree formulation: a multiparameter optimization of the color and taste of final puree products can be obtained using only the Vis-NIR spectral data of single-cultivar purees.

An innovative chemometric method was developed to exploit visible and near-infrared (Vis-NIR) spectroscopy to guide food formulation to reach the anticipated and constant quality of final products. First, a total of 671 spectral variables related to the puree quality characteristics were identified by spectral variable selection methods. Second, the concentration profiles from multivariate curve resolution-alternative least squares (MCR-ALS) made it possible to reconstruct the identified spectral variables of formulated purees. Partial least square based on the reconstructed Vis-NIR spectral variables was evidenced to predict the final puree quality, such as a* values (RPD = 3.30), total sugars (RPD = 2.64), titratable acidity (RPD = 2.55) and malic acid (RPD = 2.67), based only on the spectral data of composed puree cultivars. These results open the possibility of controlling puree formulation: a multiparameter optimization of the color and taste of final puree products can be obtained using only the Vis-NIR spectral data of single-cultivar purees.

International audience | An innovative chemometric method was developed to exploit visible and near-infrared (Vis-NIR) spectroscopy to guide food formulation to reach the anticipated and constant quality of final products. First, a total of 671 spectral variables related to the puree quality characteristics were identified by spectral variable selection methods. Second, the concentration profiles from multivariate curve resolution-alternative least squares (MCR-ALS) made it possible to reconstruct the identified spectral variables of formulated purees. Partial least square based on the reconstructed Vis-NIR spectral variables was evidenced to predict the final puree quality, such as a* values (RPD = 3.30), total sugars (RPD = 2.64), titratable acidity (RPD = 2.55) and malic acid (RPD = 2.67), based only on the spectral data of composed puree cultivars. These results open the possibility of controlling puree formulation: a multiparameter optimization of the color and taste of final puree products can be obtained using only the VisNIR spectral data of single-cultivar purees.

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.

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.

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.

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.

Changes in the quality of blue honeysuckle fruit following exposure to air or controlled atmospheres (CA1: 20% O2 and 20% CO2; CA2: 5% O2 and 20% CO2; CA3: 5% O2 and 10% CO2) were investigated. The 'Lanjingling’ blue honeysuckle was stored at a temperature of −1 °C for a duration of 28 d. An elevated concentration of CO2 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% CO2) 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% O2 and 5% CO2, 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% O2 and 20% CO2 can be deemed an effective method of blue honeysuckle for prolonging storage life and safeguarding its bioactive components.

Changes in the quality of blue honeysuckle fruit following exposure to air or controlled atmospheres (CA1: 20% O2 and 20% CO2; CA2: 5% O2 and 20% CO2; CA3: 5% O2 and 10% CO2) were investigated. The 'Lanjingling’ blue honeysuckle was stored at a temperature of −1 °C for a duration of 28 d. An elevated concentration of CO2 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% CO2) 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% O2 and 5% CO2, 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% O2 and 20% CO2 can be deemed an effective method of blue honeysuckle for prolonging storage life and safeguarding its bioactive components.

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.

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 (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.

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.

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.

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.

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.