Abstract:Food is rich in a variety of chemical components, which have undergone a series of processes such as processing, release, degradation, in vivo absorption and metabolism, and are finally utilized by the body. With the in-depth development of food chemistry and food nutrition, the key changes, influencing factors and regulation methods of food components in the process from farm to table and human body have been highly concerned and widely studied. In this paper, the changes of food nutritional components in food processing in vitro and digestion and absorption in vivo as well as the health benefits to human body were reviewed. The changes of nutrient components during food processing and human intake were introduced, including the breaking of food matrix, the release of components, digestion and absorption in the body, and the healthy function of nutrient functional components (chemical structure oxidation and degradation). The key influencing factors in the process from farm to table and human body were analyzed, including the methods and conditions of food processing, the original state of food, the types of food, the properties of food matrix and the state of human health. The strategies for strengthening nutritional function of food from farm to table and human body were summarized, including optimization of processing methods, selection of dietary sources, selection of food forms, optimization of cooking methods and selection of delivery system of nutritional functional components. The sustainable development of food nutrition industry in the future is prospected.

Abstract:The development of omics technologies (OTs) has expanded our understanding of growth and development, synthesis of metabolites, and the mechanisms of metabolic regulation in Monascus sp.. In this study, the current status and hot topics of Monascus sp. omics research in recent years were summarized. The application of OTs in Monascus sp. was analyzed from multiple dimensions, including genomics, transcriptomics, proteomics, and metabolomics. In Monascus sp., genomics was mainly used to explore the evolutionary status, predict and mine gene clusters, and analyze homologous genes and metabolic pathways. Transcriptomics focused on the transcriptional expression of genes or gene clusters during growth and metabolism of Monascus sp., as well as the prediction and exploration of metabolism regulatory mechanisms and novel transcriptional regulatory factors. Proteomics mainly involved the functional analysis of important enzymes in metabolism process and the metabolic mechanisms they participate in. Metabolomics aimed to analyze potential metabolic mechanisms based on metabolites in Monascus sp.. The challenges of research and production faced by a representative secondary metabolite, monascus pigments were also discussed. To regulate the pigments production efficiently, precisely, and safely, various control technologies based on OTs were classified and summarized, including strain selection and breeding, culture medium optimization, chemical and physical regulation, and strain metabolic modification. Finally, prospects for the comprehensive application of OTs to solve the metabolic regulation of the pigments were proposed, aiming to provide references for promoting research of Monascus sp. and the production of its metabolites.

Abstract:i>Monascus is a kind of medicinal and edible filamentous fungus, which is widely used in food, medicine, biocatalysis and other fields. Monacolin K is the main metabolic functional active product of Monascus, with biological activities such as lipid-lowering, antifatigue, antibacterial, anticancer, and neuroprotective. It is widely recognized as an ideal drug for lowering cholesterol. The difference of monacolin K gene cluster synthesis between Monascus and Aspergillus terreus was compared, and the synthetic pathway of monacolin K produced by Monascus was expounded. The application and potential of monacolin K in fields such as medicine, health food, and feed were summarized and prospected. Due to the toxic effects of the fungal toxin citrinin produced during the fermentation of natural Monascus to produce functional substances, which has a toxic effect on the kidneys, liver, heart, and reproductive system, it limits the industrial development of Monascus. Improving the monacolin K production of Monascus and reducing the production of citrinin are important ways to solve the development issues of functional Monascus. Therefore, the technical methods for optimizing monacolin K production by Monascus and avoiding citrinin accumulation from aspects such as mutation breeding, construction of engineering strains, optimization of culture media, and control of environmental factors was summarized. The synthesis pathway, biological activity, and application fields of monacolin K produced by Monascus, as well as the current research status of biotechnology methods for high production of monacolin K were summarized. Based on this, the problems in the production of monacolin K by Monascus were analyzed, and suggestions and prospects were proposed, in order to provide theoretical basis and reference for the research and development of new types of Monascus health food.

Abstract:To study the effect of partially hydrolyzed guar gum (PHGG) on learning and memory ability of APP/PS1 Alzheimer's disease (AD) mice, PHGG dietary intervention was taken by APP/PS1 mice for 3 months, and the learning and memory ability was measured by Morris water maze and step-through passive avoidance tests. The morphological changes of brain tissue and the number of neurons were observed, and the expression of apoptosis-related proteins was determined by Western blotting. Furthermore, the expression levels of amyloid beta protein and phosphorylated Tau protein were detected by immunofluorescence. The result showed that compared with APP/PS1 model mice, PHGG significantly improved the reactivity, coarseness and lordokyphosis. The time and distance of entering the target quadrant, and the number of crossing platform by PHGG treatment were increased by 81.6%, 58.0% and 171.4% (P<0.05), respectively. Meanwhile, the number of neurons in the cerebral cortex and hippocampus was increased. The protein expression ratio of Bcl-2/Bax in whole brain tissue was increased by 54.9%, compared to APP/PS1 mice (P<0.05). The expressions of β-amyloid protein in cerebral cortex and hippocampus were decreased by 32.0% and 55.0% (P<0.05), and the expressions of phosphorylated Tau protein were decreased by 52.3% and 62.6% (P<0.01), respectively. Furthermore, PHGG treatment significantly reduced the expression of TLR4 (by 42.0%) and NF-κB (by 46.8%) proteins in whole brain tissue of APP/PS1 mice (P<0.05). PHGG could significantly improve the cognitive impairment of AD mice, and inhibit the cell apoptosis and neuronal damage in the cerebral cortex and hippocampus of brain tissue by regulating TLR4/NF-κB signaling pathway. The results provided a scientific basis for the development of PHGG as a functional food ingredient for anti-AD.

Abstract:Royal jelly has the function of delaying aging and has a certain protective effect on kidney damage caused by various conditions. However, it is not clear whether royal jelly also has an effect on age-related kidney function decline. To study the effect of royal jelly on the kidneys of aging mice, SPF Kunming mice were used as the research subjects. Fifty mice (equal number of females and males) were divided into 5 groups. The control group was injected and gavaged with normal saline, while the other four groups were injected with D-galactose to establish a mouse aging model. Meanwhile, the aging model group was gavaged with normal saline, two positive control groups were gavaged with vitamin E and Liuwei Dihuang pills, respectively, and the experimental group was gavaged with royal jelly. The experiment lasted for 90 days. The kidney function was evaluated through kidney index, kidney histopathological sections, and the levels of blood urea nitrogen and creatinine. The total antioxidant capacity and superoxide dismutase levels were used to evaluate the tissue's antioxidant capacity. Untargeted serum metabolomics were performed to identify the main metabolites and metabolic pathways regulated by royal jelly. The results showed that there were significant changes in the kidneys of aging mice, with significant dilation of the renal capsule and atrophy of the glomerular. The blood urea nitrogen and creatinine levels in the aging mice significantly increased, while the total antioxidant capacity and superoxide dismutase levels significantly decreased. However, feeding with Vitamin E, Liuwei Dihuang pills, and royal jelly alleviated the decline in kidney physiological function and antioxidant capacity to varying degrees. Royal jelly and Liuwei Dihuang pill groups exhibited better protection for the kidney disease caused by aging. Serum metabolomic results of aging mice showed that compared to the Liuwei Dihuang pills group, royal jelly had more targeted regulation on metabolism, mainly involved in amino acid metabolism, energy metabolism, and lipid metabolism. Compared to the model group, total 308 and 343 significant changed metabolites were found and enriched in 19 and 15 metabolic pathways in female and male mice of royal jelly groups, respectively. These metabolic pathways were mainly associated with antioxidation, improved energy supply, and maintenance of basic kidney functions. The results indicated royal jelly had certain protective effect on the kidneys of D-galactose induced aging mice and would provide a theoretical basis for the further development of royal jelly as a functional food.

Abstract:Polypeptides are important active substances in Agaricus blazei. To investigate the anti-aging effect of Agaricus blazei polypeptide (ABp), ABp was prepared by hydrolyzing Agaricus blazei protein with pepsin, and purified by column chromatography using a protein purification system. A mouse aging model was established by injecting D-galactose. The effects of ABp on aging model mice were investigated by behavioral experiments, serum biochemical indicators and transcriptome sequencing. Furthermore, Western blotting was used to explore the potential mechanism of ABp. The results indicated that the molecular weight of ABp was 3.3 kDa after separation and purification. ABp could significantly inhibit the elevated levels of reactive oxygen species and malondialdehyde in mouse serum caused by D-galactose, significantly enhanced the total antioxidant capacity and catalase activity in mouse serum. The transcriptome sequencing results showed significant differences in the expression levels of 295 genes in mouse hippocampus between ABp group and model group. Compared with the aging model group, ABp upregulated 79 genes and downregulated 216 genes in mouse hippocampus. The results of Western blotting indicated that the potential mechanism of ABp anti-aging might be related to the Keap1/Nrf2/P53 signaling pathway. This study aims to provide a theoretical basis for the development of anti-aging functional food of Agaricus blazei.

Abstract:Walnut polyphenols (WP) is an important bioactive substance in defatted walnut and has important development and application value. In order to evaluate the antidepressant effect of WP on corticosterone-induced damage of rat pheochromocytoma (PC12) cells by cell viability, cell apoptosis, leakage of extracellular lactate dehydrogenase, and intracellular calcium level, and investigated its mechanisms by western blotting. The results showed that WP (75,150μg/mL) pretreatment could protect cell by significantly reversing the cell viability decrease, cell apoptosis, LDH release increase, and overload of intracellular calcium in PC12 cells treated with corticosterone. In addition, WP significantly increased the activity of cAMP-dependent protein kinase A (PKA), reduced the level of Ser133 phosphorylation of cAMP response element binding protein (CREB) and the expression of downstream target protein brain-derived neurotrophic factor (BDNF), which were decreased by corticosterone treatment. Furthermore, pretreatment with PKA inhibitor H89 abolished the protective effects of WP on corticosterone induced PC12 cells, indicating that up-regulation of PKA/CREB/BDNF neurotrophic signaling pathway was required for WP neuroprotective effects against corticosterone. These results suggested that WP might have potential antidepressant activity and be an important material basis in the antidepressant effect of walnut diet. The cytoprotective effect of WP on PC12 cells was related to the up-regulation of PKA/CREB/BDNF neurotrophic signaling pathway. The research results aimed to explore the potential antidepressant activity and mechanism of walnut polyphenols, and provided theoretical reference for the high-value utilization of walnut meal.

Abstract:D-Allulose, an important rare sugar, has a wide range of application value in food, cosmetics and pharmaceutical industry. At present, D-allulose production methods in industry are mainly biological methods. Due to the disadvantages of the traditional enzymatic methods, such as complicated steps, high cost and difficulty in product separation and purification, it was difficult to meet the needs of industrial production. In recent years, whole cell synthesis systems have attracted much attention because of their low cost, convenient operation and easy separation. The study was aimed at efficient heterologously expressing of D-allulose 3-epimease (DAEase) originated from Caballeronia insecticola in production safety strains Bacillus subtilis (B. subtilis) WB800 to catalyze D-fructose to D-allulose. Recombinant strains with different constitutive promoters were firstly designed and constructed to improve the expression of DAEase in B. subtilis. Then, the conditions of the whole cell reaction system (temperature, pH, metal ions, cell concentration) were optimized, and the conversion efficiency of D-fructose under different substrate concentrations was explored. The results showed that the promoter PylbP could maximally express recombinant DAEase in B. subtilis WB800, and the optimal temperature, pH and metal ions of recombinant DAEase in whole cell reaction system were 65℃, 9.5 and 5mmol/L Mg²⁺, respectively. The whole cell reaction could almost reach to equilibrium in 4 h with a conversion rate of 30.06% when 500g/L D-fructose was added as substrate. This research provided experimental and theoretical basis for producing D-allulose industrially.

Abstract:Aging process during storage is a key process in improving the quality of Baijiu. Laobaigan base Baijiu as a research project was stored for 156 d with three different methods, natural temperature storage (room temperature), constant temperature storage (40℃) and alternating temperature storage (40℃ for 12h and cooled naturally for 12h every day). Headspace solid-phase microextraction combined with GC-MS and GC-O were used to study the effects of different aging methods on the changes of volatile flavor components in base Baijiu. A total of 55 volatile flavor components was identified, 43 out of these with relatively high contents and Baijiu flavor characteristics were monitored during 156 d storage by external standard quantity, and the changes of odor activity value were calculated then. Results showed that the contents of most esters increased gradually with time at alternative temperature storage, and the contents of most esters increased first and then decreased at constant temperature. The contents of ethyl lactate, ethyl acetate, isoamyl acetate, hexyl acetate, ethyl hexanoate, 3-methylbutyl hexanoate, ethyl 4-methyl valerate, ethyl nonanoate, ethyl undecanoate, ethyl tetradecanoate, ethyl oleate, diethyl succinate, diethyl azelate, ethyl phenylacetate at alternative temperature storage were higher than those at natural temperature or constant temperature storages on the 156th day. However, only the content of ethyl palmitate at constant temperature storages was higher than those of the other two groups on the 156th day. Nineteen compounds with odor activity value greater than 1 were potent odorants, they significantly contributed to the overall aroma of Baijiu. The results also showed that the time of constant temperature treatment should not be too long, or the content of esters would regress. The recommended time for constant temperature storage was 128 days. The alternating temperature storage could increase the content of esters and shortened the aging time to a certain extent. These findings pointed out the direction for process optimization in the productive process of base Baijiu, and laid the foundation for the company to optimize the liquor production design and improve product quality.

Abstract:In order to investigate the correlation between the transcriptionally active Clostridia and the volatile organic acids metabolism in the fermented grains for the production of Chinese strong flavor Baijiu (CSFB), the methods of macrotranscriptomics and gas chromatography-mass spectrometry were used to determine the composition, succession, function of active Clostridia, and types of organic acids in fermented grains of CSFB. The results showed that there were 6 orders, 27 families, 148 genera assigned into Clostridia detected, and Heliobacteriaceae was dominat bacteria at the family level. The average relative abundance of clostridial community reached highest level at 15th day for the fermentation. The whole fermentation process could be divided into three phases according to the abundance variation of clostridial community, early fermentation (3-7d), middle fermentation (7-25d), and late fermentation (25-60d). Various degrees of correlations had been observed between the top 10 genera and eight volatile organic acids, such as acetic acid, butyric acid, caproic acid and etc.. The KEGG functional annotation indicated that Clostridia was mainly involved in carbohydrate metabolism, translation, and energy metabolism. The synthesis pathway of acetic acid and butyric acid involved 25 genes and 22 carbohydrate enzymes from 12 identifiable genera and unidentified genera, and their related genes had the highest expression level at 45th day for the fermentation, with Clostridium was the main contributor. This study aimed to provide basic data and theoretical support for further revealing the solid-state brewing mechanism of CSFB, and help clarify the composition and function of active clostridial communities in the complex microecosystem of fermented grains for the production of CSFB.

Abstract:Flavonoids can regulate blood sugar levels by inhibiting the activity of α-amylase. However, there were very limited research on the inhibitory mechanism and structure-activity relationship of flavonoids on α-amylase. Especially, the effects of hydroxylation on the B ring and glycosylation on the C ring related to the inhibitory ability of flavonoids on α-amylase were still unclear. Therefore, in order to explore the inhibitory mechanism and structure-activity relationship of flavonoids on α-amylase, the types of inhibition, fluorescence quenching properties, conformational changes, binding force and binding sites of three flavonoids (rutin, quercetin and kaempferol) were investigated in this study. The results showed that kaempferol had the strongest ability to inhibit α-amylase and rutin had the weakest ability to inhibit α-amylase, respectively. The inhibitory effect of flavonoids was attenuated by glycosylation at C3 on the C ring and hydroxylation at C3' on the B ring. The quenching affinity was enhanced by a glycosyl group at C3 on the C ring and weakened by a hydroxyl group at C3' on the B ring. Hydrogen bonds and hydrophobic interactions caused the spontaneous binding between the flavonoids and α-amylase, which changed structure and hydrophobic microenvironment of α-amylase, and inhibited α-amylase activity effectively. The purpose of this study was to provide theoretical support for the development and application of hypoglycemic foods rich in flavonoids.

Abstract:To develop biodegradable composite films with fresh-keeping effects, caffeic acid (CA) was covalently grafted with amino-mesoporous silica nanoparticles (NH₂-MSN) via a carbodiimide mediated coupling reaction and loaded with eugenol (EG) to obtain eugenol/caffeic acid-mesoporous silica nanoparticles (EG/CA-MSN). Zein was used as film-forming matrix and EG/CA-MSN used as functional filler. Eugenol/caffeic acid-mesoporous silica nanoparticles/Zein (EG/CA-MSN/Zein) composite films were further obtained by flow casting method. The effects of the added amount of EG/CA-MSN on the physicochemical and functional properties of the composite films were investigated. SEM and FTIR results showed that EG/CA-MSN demonstrated good biocompatibility and intermolecular interactions with zein film matrix. The addition of EG/CA-MSN could improve the barrier properties and mechanical properties of the composite films. When the mass fraction of EG/CA-MSN was 9%, and the water vapor transmission rate of composite films was the lowest [3.11×10-9g· mm/(m²·s·Pa)],the tensile strength could reach 18.86MPa,which was significantly better than the single zein film. When the mass fraction of EG/CA-MSN was 12%,the composite films demonstrated decent antioxidant and bacteriostatic properties. The free radical scavenging rate of DPPH and ABTS⁺ increased to 78.28% and 85.49%,respectively. The diameter of inhibition zone against Escherichia coli and Staphyloccus aureus reached 13.57mm and 12.38mm,respectively. The application of the composite films in the preservation of frozen fillets could effectively delay the total volatile basic nitrogen and fat oxidation during storage. The developed EG/CA-MSN/Zein composite film had potential applications value in the preservation of aquatic products.

Abstract:In order to investigate the effect of trehalose on the retrogradation properties of rice starch, the molecular structure, water distribution, rheological and thermodynamic properties were studied by means of atomic force microscope, low-field nuclear magnetic resonance, Fourier transform infrared spectroscopy and differential scanning calorimetry analysis. The results showed that the leached straight chain amylose contents of rice starch with the addition of 1.6% trehalose (T-starch), which were stored at 4℃ for 3h and 24h were decreased by 8.6% and 11.5% compared with rice starch, respectively. The arrangement of the starch molecular chains trended to aggregate to an ordered structure with the retrogradation. However, the addition of trehalose could inhibit the aggregation. The order degree of rice starch increased by 19.0%, but the order degree of T-starch only increased by 3.0% after retrogradation for 24h, indicating that the trehalose could significantly decrease the proportion of short-term order structure of rice starch. The binding ability of T-starch to water molecules (strongly and weakly bound water) was significantly higher than that of rice starch (P<0.05). The free water precipitation and recrystallization in T-starch system were blocked, which was one of the reasons for inhibiting the short-term retrogradation of starch. After the addition of trehalose, both regenerative enthalpy and retrogradation degree of the long-term retrogradation of T-starch were significantly reduced. And this advantage brought by trehalose became more and more prominent with the extension of aging time, and the long-term retrogradation enthalpy of T-starch system was significantly reduced. Therefore, trehalose could not only effectively inhibit the short-term retrogradation of starch, but also had a good inhibitory effect on long-term retrogradation.

Abstract:To reduce the degradation of inosinic acid in marine fishes for maintaining the freshness of the fish, separation and purification of acid phosphatase (ACP) from Lateolabrax maculatus (sea bass) were performed using NaAc-HAc (pH 5.0) buffer extraction, graded precipitation separation by saturated ammonium sulfate, and anion-exchange column and dextran gel column purification. The enzymatic properties of ACP in the liver of sea bass were studied and potential natural ACP inhibitors were screened using virtual screening and molecular docking techniques. The results showed that two isoenzymes (ACP I and ACP Ⅱ) were isolated and purified. ACP I had a specific activity of 6.57U/mg and was purified to 36.50 times of the original activity with a recovery rate of 9.96%. The specific activity of ACP Ⅱ was 4.62U/mg and it had a recovery rate of 6.07% after being purified to 25.69 times of the original activity. The K_m of ACP I with relatively higher recovery rate and purification factor in sea bass was 3.174mmol/L and v_max was 0.982μmol/(L·min). The optimum temperature and pH of ACP I were 30℃ and 5.0. The secondary structure of ACP I had 14.10% α-helix, 35.00% β-fold, 18.20% β-turn and 32.60% random coil. The five polyphenol compounds as ACP inhibitors were screened virtually, and interacted with ACP mainly by hydrogen bonding and hydrophobic forces. In a certain concentration range (0-1mmol/L), all the five polyphenol compounds could effectively inhibit the ACP activity, and the higher the concentration, the better the inhibition effect. The research could provide a theoretical basis for flavor and quality control of aquatic products during storage.

Abstract:In order to reduce the economic loss caused by postharvest deterioration of Lentinus edodes, based on instant controlled pressure drop puffing (Franch for Détente Instantanée Contrlée,DIC) technology, L. edodes was applied to develop non-fried L. edodes crisps. The effects of procedure sequence of osmotic dehydration (OD), osmotic agent types and mass fractions of OD solution, including 0,10%, 20%, 30%, 40% maltodextrin (MD), 10% whey protein isolate (WPI), and composite osmotic agents of 20% MD+10% WPI, on the average drying rate, total color difference, puffing degree, rehydration ratio, hardness and crispness of DIC dried L. edodes crisps were investigated. Low field nuclear magnetic resonance (LF-NMR) was used to investigate the effects of OD pretreatment on the water composition and status distribution of L. edodes. The results of procedure sequence of OD research showed that compared with the OD pretreatment before heat pump drying (HPD), OD pretreatment after HPD could significantly improve the puffing degree, rehydration ratio, crispness, and decrease the total color difference of L. edodes crisps (P<0.05). The results of osmotic agent types and concentration research showed that compared with the control group, OD pretreatment could significantly improve the puffing degree and rehydration ratio of L. edodes crisps (P<0.05), but the effects of OD pretreatment on the average drying rate, total color difference, hardness and crispness were dependent on the composition of osmotic solution. The optimal procedure was that L. edodes was firstly heat pump dried to moisture content of 70% in wet basis, and then OD pretreatment was performed with 20% MD+10% WPI. The OD treated L. edodes were subsequently pre-dried by HPD to moisture content of 35%±2%, and finally the equilibrated samples were performed by DIC. The quality characteristics of L. edodes crisps under aforementioned optimal procedure were superior. LF-NMR results revealed that after OD pretreatment, the transverse relaxation time (T₂) was shifted to the left and the amplitude increased with the increase of mass fraction of solute in the osmotic solution. Whereas the proportion of the free water was decreased but the bound water and immobilized increased. After HPD, except for 30% and 40% MD pretreatment, water in L. edodes was mainly comprised of loosely bound water and immobilized water, but the proportion of free water was very low (0.41%-4.67%). Compared with the control group, after HPD the proportion of free water (with the exception of 10% WPI pretreatment) and immobilized water in L. edodes was significantly decreased, but the proportion of loosely bound water was significantly increased (P<0.05). Pearson correlation analysis indicated that the OD pretreatment had greater influence on the quality of L. edodes crisps than HPD process, and the quality characteristics were closely related to LF-NMR relaxation parameters. The puffing driving force of L. edodes depended mainly on the immobilized and bound water especially loosely bound water, but it had nothing to do with the free water. This study aimed to provide theoretical basis and technical reference for the DIC technology of non-fried L. edodes crisps.

Abstract:In the online environment, public sentiment events on food safety are characterized by their rapid disseminations and high impacts. If public sentiment issues were not taken seriously and addressed in a timely manner, they are highly likely to lead to sudden mass incidents. Constructing a robust online public sentiment management index system for food safety helps identify, evaluate, predict and respond to public opinion. This paper firstly explained the mechanism of food safety online public sentiment dissemination. Secondly, the technical architecture of food safety online public sentiment analysis system based on big data was used to build a food safety online public sentiment index system and establishes a food safety online public sentiment early warning model. Finally, solutions to early warning of online public sentiment on the topic of food safety in the era of big data from the government, media and enterprises aspects were proposed. The use of natural language processing and information retrieval (NLPIR) and other technical means to collect, understand, analyze, extract and ultimately dive deeper into information on public sentiment on the internet was explained, so that public sentiment could be detected, warned and dealt with early, and public concerns could be addressed. With the public's preferences for expressing emotions and making personal statements via the internet, the government, the media, the public and companies should give priority to early warnings of public sentiment on food safety. How to detect, warn, handle and mitigate online public sentiment events early is of great significance to the government and relevant departments.