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In this study, mango core-shell cellulose nanofibers (CNFs) were prepared successfully after hypochlorite bleaching, alkalization TEMPO oxidation and high pressure homogenization. The effects of pH and ionic strength on emulsion stability were also investigated. The results showed that the mango core-shell CNFs prepared by TEMPO oxidation and high pressure homogenization method maintained the basic structure of cellulose, and some hydroxyl groups were oxidized to carboxyl group. The cellulose crystallinity was reduced to 57%, which was more sensitive to temperature, but still maintained high thermal stability. The particle size of Pickering emulsion stabilized by mango core-shell CNFs decreased significantly with the increase of pH. The smallest particle size was 469.5 nm at pH11, and the particle size distribution was more uniform. The 30 day CI was 58.8%, showing good stability. The ionic strength had a great influence on the stability of mango core-shell CNFs Pickering emulsion. Under the ionic strength of 50~100 mmol/L, a large number of positively charged sodium ions aggregated on the surface of CNFs and neutralize the negative charge on the surface, which weakened the electrostatic repulsion between droplets and makes droplets more likely to aggregate, which was not conductive to the stability of the emulsion. In summary, the mango core-shell CNFs could be used as excellent solid particles in Pickering emulsion, which would provide a new for the high value utilization of mango core-shell.

The polyphenols and antioxidant activities of different mango cultivars were studied. Polyphenols from four commercial mango (Ivory, Yu, Zihua and Sannian) mango kernels were extracted, determined and analyzed statistically. The results showed that mango kernel contained abundant polyphenolic compounds and had good antioxidant activity. Among them, the content of polyphenol in Zihua mango kernel was the highest and its antioxidant activity was the strongest, followed by Ivory mango kernel and Sannian mango kernel, and that in Yu mango kernel was the worst. There were great differences in the extracts of mango kernels among the four cultivars, which were easy to distinguish, and there was a positive correlation between the determination indexes. Among them, total phenols and hydrolyzed tannins were significantly correlated with in vitro antioxidant activities (P

Polyphenols and dietary fiber can form complexes through their interactions. In order to investigate the interaction mechanism between polyphenols and dietary fibers, and the structure and morphology of complexes formed by them, this paper selected epigallocatechin gallate and oat β-glucan as the raw materials for the preparation of the complexes and their structural characterization. The results indicated that the formation of the complex of EGCG and oat β-glucan was related to the concentration and pH of EGCG, EGCG and oat β-glucan could form a complex with a particle size of 1.7 μm and a relatively uniform particle size (dispersion coefficient 0.38) in an aqueous solution with a mass ratio of 0.8:1 and pH5. Through transmission electron microscopy, the formation of regular spherical particles between EGCG and BG were clearly observed. Isothermal Titration Calorimetry (ITC) measurement was used to characterize the EGCG-BG complex. The binding mechanism at 25 °C clearly provided that the binding between EGCG and BG were mainly non-covalent interaction (such as hydrogen bonding and hydrophobic interaction). The above experimental results could indicate that EGCG and BG could spontaneously form a complex through non-covalent interactions. In summary, the findings of this study would provide a theoretical reference and research basis for the use of different polyphenol-oat β-glucan complexes as functional food ingredients or as bioactive materials.

Cellulose nanocrystalline (cncs) were prepared from bagasse as raw material to stabilize the Pickering emulsion to examine the effect of pH and ionic strength on emulsion stability. The results showed that the CNCs obtained by hydrolysis had a length of about 120 nm and a crystallinity of 70%. The particle size of the Pickering emulsion stabilized by CNCs decreased with the increase of the pH value of the preparation conditions. Under the condition of pH 11, the emulsion was relatively uniform due to deprotonation. In addition, the particle size of the Pickering emulsion stabilized by CNCs increased with the concentration of salt ions. At a concentration of 100 mmol/L, the electrostatic repulsion reduced due to the electrostatic shielding effect of salt ions, the emulsion broke, and the layering became more obvious. The experimental results showed that bagasse CNCs had potential in preparing Pickering emulsion as solid particles, and would provide new ideas for the utilization of bagasse.

BackgroundAs an environmental pollutant, 1-bromopropane (1-BP) is ubiquitous in the living environment. However, its health effects on the general population are still unclear. ObjectiveTo assess the associations between urinary 1-BP metabolite and blood routine indices in a Chinese community population. MethodsA total of 3512 community residents aged 18-80 years from the baseline of the Wuhan-Zhuhai cohort were included in our study. The demographic characteristics, disease history, and lifestyles of the participants were collected through questionnaires. Height, weight, blood pressure, and other anthropometrics were collected through physical examination. Blood routine indicators were tested using an automated hematology analyzer. Urinary 1-BP metabolite N-Acetyl-S-(n-propyl)-L-cysteine (BPMA) was measured by ultra-high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Generalized linear models and logistic regression models were used to assess the associations of urinary BPMA with blood routine indices and the risks of abnormal blood routine indices, respectively. Besides, stratified analysis and effect modification analysis were further conducted to investigate the effects of individual characteristics and lifestyles on the associations of urinary BPMA with blood routine indices. All models were adjusted for gender, age, and other potential confounders.ResultsThe mean age of the study population (30.1% male) was (52.78±12.77) years. The median (P25, P75) level of urinary BPMA adjusted for urinary creatinine was 0.90 (0.50, 1.73) mg·mol−1. In the analysis with target indicator as continuous variable, each 1-unit increase in natural logarithm-transformed urinary BMPA level was associated with a 0.078×109 L−1, 0.031×109 L−1, 0.307%, 3.518 g·L−1, and 2.469×109 L−1 decrease in white blood cell, lymphocyte, lymphocyte percentage, mean corpuscular hemoglobin concentration, and platelet levels, respectively (all Ps

Dimple surface texture with a matrix-distribution was prepared on the surface of 316L stainless steel by laser processing technology. Orthogonal experiment was established by taking as facters the geometrical parameters of dimple shape, area, and interval between two dimples. The effect of laser surface texturing on the tribological behavior of 316L stainless steel under dry friction was investigated. Range and variance analysis were used to analyze the mass loss of 316L stainless steel. The surface and worn morphologies of surface textured 316L stainless steel were characterized by scanning electron microscopy. The results show that the friction coefficients of surface textured 316L stainless steels were higher than that of the polished 316L stainless steel, which was attributed to the increase of surface roughness after laser processing. However, the mass loss values of surface textured 316L stainless steel samples were significantly lower in comparison with the polished 316L stainless steel because the obtained surface texture provided positive effects of capturing wear debris and reducing friction contact area, thus contributing to significant improvement in wear resistance of 316L stainless steel.