To investigate the protective mechanism of yeast hydrolysate （YH） on human umbilical vein endothelial cell injury induced by H2O2，antioxidant activity of YH was studied.The results show that the median effective concentration （EC50） of YH on DPPH scavenging is 1.85 mg/mL，showing good antioxidant activity.And YH of high-dose （500 μg/mL） can significantly alleviate the cell proliferation inhibition induced by H₂O₂，reduce malondialdehyde （MDA） production and increase the level of superoxide dismutase （SOD），thereby resisting cell oxidative damage of HUVEC caused by H₂O₂.Moreover，transcriptomics sequencing reveals that YH  can significantly up-regulate the expression of genes SOD2 and HMOX1.The research results not only provide basic data for YH to reduce endothelial cell oxidative damage，but also provide a theoretical basis for the application of YH in the fields of antioxidation functional foods and medicine.

In order to improve the anti-digestibility of rice starch，the change law of digestibility and multi-scale structures of the fermented rice starch-proanthocyanidins complex，including the particle morphology，lamellar structure，crystalline structure，helical structure and short-range ordered structure，were systematically studied with modern analytical techniques and the method of fermentation and interaction with proanthocyanidins.Meanwhile，the molecular mechanism of rice starch anti-digestibility controlling by fermentation and combination with proanthocyanidins was revealed.The results indicates that the rapidly digestible starch and slow digestible starch contents of the fermented rice starch after interacting with proanthocyanidins are decreased，whereas the resistant starch contents are significantly increased.Moreover，the interaction between proanthocyanidins and fermented rice starch can promote the formation of specific ordered structure.And partial proanthocyanidins in the amorphous region can be released to inhibit the action of amylase during the digestion process，which synergisticly reduces the digestibility of fermented rice starch.The results provides foundations for improving the nutritional functions of fermented rice products.

The rhamnolipids components that fermented by Pseudomonas aeruginosa 1.10452 were analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS) in order to explore the potential of rhamnolipids as biosurfactants, and the critical micelle concentration (CMC), emulsifying activity, foam property and antibacterial activity of rhamnolipids were measured. The results of component analysis shows that the rhamnolipids are mainly composed of 9 homologues, and dirhamnolipid is the main component. The critical micelle concentration of rhamnolipids is 80mg/L and its surface activity is better than that of sodium dodecyl sulfate (SDS). Compared with the control group, rhamnolipids shows excellent emulsifying properties on soybean oil (63.75%), liquid para-ffin (65.69%) and n-hexane (52.54%). The foaming ability and foam stability of rhamnolipids are close to that of SDS in pure water, but significantly better than that of SDS in hard water. Furthermore, rhamnolipids exhibits good surface activity and emulsifying activity at different temperature (-20~121℃), ionic strength (0~25 g/L) and pH (6~13). The results of inhibition zone test show that rhamnolipids has strong inhibition ability to Staphylococcus aureus, Escherichia coli and Candida albicans.

In order to study the purification method of octenyl succinate dextrin ester（OSDE） and its emulsifying properties，this study prepared OSDE with the aqueous phase method by using dextrin and octenyl succinic anhydride as the main raw materials.The product was purified by three methods including ethanol washing method，ion exchange method and membrane separation method.The results show that the purification effect of ion exchange method is the best and is friendly to subsequent determination of substitution degree；the purification effect of membrane separation method was the second；the ethanol washing method shows the worst purification effect.The morphology and group change of OSDE obtained by ion exchange method were analyzed.Scanning electron microscopy（SEM） shows that it is irregular lamellar，with sharp edges and corners，smooth surface，and slightly grooved or spotted corrosion areas；FT-IR analysis shows that the octenyl succinic acid group is successfully introduced into the maltodextrin molecule.After esterification modification，OSDEs viscosity-increasing ability is improved，and the shear thinning property，which is positively correlated with the degree of substitution，is wea-kened；the emulsion stability of the emulsion increases with increase of the degree of substitution of OSDE.Compared with the commonly used emulsifier gum arabic，the soybean oil emulsion of OSDE （DS0.0416） is slightly weaker in emulsification stability，but its rheological properties and microscopic morphology of the emulsion are similar to those of the commonly used emulsifier gum arabic but with lower cost.It shows that OSDE （DS0.0416） has a viable prospect as a substitute for expensive gum arabic in the application of emulsifiers and microcapsule wall materials.

Chinese chestnut is a Chinese characteristic economic forest fruit, and its planting area and output in China ranked in the world’s top. It is favored by consumers as one of the most important snack foods and food supplements. However, the content of starch in chestnut is relatively high. After processing, the content of fast-digested starch is significantly increased, which can easily lead to blood glucose disorder and can increase the risk of chronic metabolic diseases such as type 2 diabetes and obesity. In addition, chestnut starch is easy to suffer retrogradation during storage, which affects the processing quality of chestnut food. Therefore, to improve the nutritional function and processing quality of chestnut-based products, chestnut starch was modified by heat-moisture treatment (HMT) together with the composition of polyphenols. The effects of structure of caffeic acid (CCA)/chlorogenic acid (CGA) on the multi-scale structure, digestion and retrogradation performance of chestnut starch-polyphenol complexes were studied by modern analytical technologies. The results show that the addition of CCA/CGA during HMT can significantly reduce the digestibility of chestnut starch. And the content of anti-enzymatic components of chestnut starch, HMT treated chestnut starch, starch-CGA complex and starch-CCA complex are 15.53%, 17.77%, 19.72% and 22.73%, respectively. Moreover, as compared with CGA, small molecular volume of CCA is more likely to form anti-enzymatic hydrolysis structure domains (short-range ordered structures and V-type crystalline structures) with chestnut starch. Low temperature storage for 7 days can promote the retrogradation of chestnut starch granules and its polyphenol complexes. During the retrogradation process, the aggregation and re-arrangement of starch molecular chains will promote the formation of more ordered short-range ordered structures and crystalline structures, but the whole retrogradation is not obvious.As compared with HMT treated chestnut starch, the addition of polyphenols can hinder the aggregation and rearrangement of starch molecular chains to form long-range ordered crystalline structures, therefore inhibiting the retrogradation of starch granules and improving their storage stability. Overall, as compared with CGA, the addition of CCA can endow chestnut starch with great anti-digestion and anti-retrogradation performance, thus providing a new way and technical support for creating high quality and healthy chestnut starch food.

In recent years, with the gradual increase of pineapple sales, the resource waste problem of pineapple peel needs to be urgently solved. Pineapple peel residue is rich in insoluble cellulose, which provides a possibility for the derivative development of cellulose extracted from pineapple peel residue. In order to discuss the potential in the preparation and application of pineapple peel cellulose nanocrystals (PCNCs), this paper prepared pineapple peel residue cellulose nanocrystals PPeNc and PTNc by sulfuric acid hydrolysis and 2,2,6,6-tetramethylpiperidine oxide (TEMPO) oxidation, respectively, and applied them to the Pickering emulsion (made into PPeNc-P and PTNc-P) for the environmental stability study. Fourier transform infrared spectroscopy, X-ray diffraction and thermal gravimetric analysis show that both PPeNc and PTNc retain the original structure of cellulose, but the crystallinity and thermal stability of PTNc are lower than those of PPeNc. Atomic force microscopy show that the aspect ratio of PTNc is as high as 54.11. As compared with PPeNc, PTNc exhibits higher aspect ratio and longer diameter. Furthermore, it is found that the stability of PTNc-P is better than that of PPeNc-P in the range of pH = 2 ~ 12, and the ionic strength is below 70 mmol/L or the oil-water ratio is below 5∶5. The storage experiment shows that the storage period of PPeNc-P is within 70 days, while PTNc-P can be stored stably for more than five months. The research results in this paper indicate that PCNCs prepared by TEMPO oxidation show greater potential in stabilizing Pickering emulsion, which provides a theoretical basis for the storage and further application of PTNc in Pickering emulsion. It is conducive to realizing the high-value utilization of pineapple peel residue.

Betanin is a water-soluble pigment with lots of biological activities.However，its stability is low and it is easily degraded under light，high pH，high temperature，enzyme and oxygen.Meanwhile，it is of low bioavailability and it's hard to be absorbed by the body.This study aimed to prepare the chitosan coated nanoliposome loaded betanin （CH-NLP） to improve the stability and bioavailability of betanin.Firstly，Nanoliposome loaded betanin （NLP） was prepared by reverse evaporation method.Then average size，Zeta potential and PDI were measured to determine the optimum concentration of CH-NLP.Meanwhile，CH-NLP，NLP and betanin were evaluated for cytotoxicity and antiproliferative activity against HepG2 cells.Results show that the optimum preparation conditions of NLP are as blow： the mass concentration of lectin is 60 mg/mL；the ratio of betanin and lectin is 1：18；the ratio of lectin and cholesterol is 6：1；ultrasound time is 8 min.The encapsulation efficiency of NLP is （42.67±1.67）%，and the drug loading is（2.63±0.42）%.The optimum concentration of chitosan binding to liposomes is 0.6%.The average size，PDI and Zeta potential are（194.60±4.43）nm，（0.29±0.05），（5.80±0.79）mV，respectively.CH-NLP shows the most potent antitumor activity against HepG2 cells，followed by NLP with the EC₅₀ of（69.46±1.75）and（108.75±2.31）μg/mL，respectively.Betanin possesses the weakest inhibitory effect against HepG2 cells.Chitosan coated liposome as a novel drug delivery system for betanin can significantly enhance its biological activity.

In order to increase the number of organisms per unit volume of fermentation broth and provide a basis for the development and application of Lactobacillus rhamnosus ZB1107-01 (LR-ZB1107-01) obtained in the early stage of the study, which is well tolerated by simulated gastrointestinal tract, this paper initially performs medium optimization and probiotic properties investigation of the strain. First, the growth curve of strain LR-ZB1107-01 in MRS medium was measured to clarify its growth pattern in liquid medium. Next, the number of viable bacteria in the fermentation broth of strain LR-ZB1107-01 was used as the detection index, and different kinds of nitrogen sources, carbon sources and growth factors were examined unilaterally to determine the optimal medium components, and response surface tests were conducted to optimize the medium ratios and select the best medium. Finally, the in vitro safety of the nitro reductase activity and amino decarboxylase activity was evaluated. The results show that the viable bacteria count concentration can reach 8.56×10⁸ CFU/mL, if three nutrients and contents that significantly affected the viable bacteria count are changed as follows: the addition of D-isoascorbic acid at 0.02%, magnesium sulfate at 0.12% and peptone at 3%, based on the glucose content of MRS medium at 2% and combined with the optimized culture conditions. The viable bacteria count is about 10.7 times higher than that in MRS medium. The in vitro safety evaluation results indicate that LR-ZB1107-01 is negative for both nitroreductase and amino acid decarboxylase, suggesting that the strain has a certain safety profile. This achievement has a certain guiding effect on the industrial production of probiotic strains and the subsequent development of products.

Ferulic acid (FA) is a common dietary polyphenol which is widely found in plant tissues. It has various biological activities such as antioxidant, anti-inflammatory, antithrombotic, and hypoglycemic. Due to the biological activities of dietary polyphenols largely depend on their digestion and absorption in vivo, studies on the intestinal metabolites of dietary polyphenols have gradually attracted researchers’ interest in recent years. Ferulic acid cannot be absorbed in the stomach and small intestine, but it can be converted into a series of hydroxyphenylpropionic acid compounds under the action of colonic esterases. This study selected three main colonic metabolites of FA, namely, 3-(3,4-dihydroxyphenyl) propionic acid (3,4diOHPPA), 3-(3-hydroxyphenyl) propionic acid (3OHPPA) and 3-phenylpropionic acid (PPA), to evaluate their antioxidant and antitumor activities. The results show that the antioxidant activity of metabolite 3,4diOHPPA is superior to that of FA and metabolites 3OHPPA and 3PPA. FA and its three metabolites can significantly inhibit the proliferation of HepG2 with EC50 values of 1.82 mmol/L (FA), 0.74 mmol/L (3,4diOHPPA), 7.77 mmol/L (3PPA) and 4.52 mmol/L (3PPA), respectively. Cell-cycle experiments show that FA and its three metabolites can regulate HepG2 cell cycle progression in an orderly manner, blocking the cell cycle in G2 or S phase. FA and its three metabolites can also induce apoptosis of HepG2 in a dose-dependent manner. Among them, FA and 3,4diOHPPA can increase the total apoptosis rate of HepG2 cells to 15.47% and 71.84% (4.23% for the control). After a pretreatment for 24 h, FA exerts its antiproliferative effects by upregulating Bax, p53 genes and downregulating CDK-2, CDK-4 genes; 3,4diOHPPA inhibits the proliferation of HepG2 by upregulating Bax, caspase-3 genes and downregulating CDK-2, CDK-4 genes. All these findings show that the anti-oxidative and anti-HepG2 cell proliferation ability of the metabolite 3,4diOHPPA is superior to that of FA. This research provides theoretical support for the antitumor activity of FA and its colonic metabolites, revealing the health benefits of FA intestinal metabolites.

Starch Ghost is an insoluble hollow sac structure that remains in GSD (Gelatinized Starch Dispersions) after starch gelatinization, named for its shape like “ghost”. Controlling the content and properties of Ghost can regulate such physicochemical properties of GSD as digestibility, electrical conductivity, viscoelasticity, etc. To further understand the effect of modified starch Ghost on the performance of starch-based products and provide a reference for its application, this paper used waxy and native potato starch with low pasting temperature and high expansion as research objects to prepare potato starch Ghost by optimizing Brabender parameters, and the influence of heat-moisture treatment temperature on the preparation and properties of two kinds of potato starch Ghost was discussed. The results show that the SEM images of heat-moisture treatment native and waxy potato starch Ghost are mostly cyst-like and thick, with swelling degrees of 1.23 ~ 2.71 and 1.58 ~ 2.78, particle sizes of 15.2 ~ 51.3 μm and 21.5 ~ 81.0 μm, and RS contents of 90.7% ~ 98.4% and 90.4% ~ 98.4%, respectively. The heat-moisture treatment increases the onset temperature but reduces the expansion volume of potato starch, and enhances the interaction between starch molecules, which leads to the decrease of the average particle size and rapid digestion starch (RDS) content of potato starch Ghost, but the content of amylose, relative crystallinity, resistant starch (RS) and the inte-grity of potato starch Ghost are increased. With the increase of heat-moisture treatment temperature, the average particle size and RDS content of potato starch Ghost show a decreasing trend, while the relative crystallinity and RS content show an increasing trend. The integrity of potato starch Ghost increases with the increase of heat-moisture treatment temperature, and the two kinds of potato starch Ghost prepared after 110 ℃ heat-moisture treatment can maintain a good hollow sac structure. By enhancing the connections between amylose and amylopectin, amylose and lipid, and amylopectin and amylopectin in starch granules, the heat-moisture treatment can significantly improve the integrity and stability of native and waxy potato starch Ghost. By controlling the conditions of heat-moisture treatment, the structure of starch Ghost can be regulated, so as to accurately produce products containing Ghost. These results have certain guiding significance for the application of heat-moisture treatment starch.