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BACKGROUND The contamination of arsenic and mercury in intertidal sediments will lead to excessive levels of arsenic and mercury in the flora and fauna of the region, which will seriously affect the ecological environment of local vegetation and further affect the survival and safety of human beings. Therefore, it is of great practical significance to study the changes in the contents and spatial distribution of arsenic and mercury in intertidal sediments. OBJECTIVES To investigate the contents of arsenic and mercury in sediments, so as to provide basic information on the pollution of arsenic and mercury in intertidal sediments. METHODS The contents of arsenic and mercury in the sediments of the study area were determined by atomic fluorescence spectrometry (AFS), and iron was selected as the normalized element to establish the environmental background values of arsenic and mercury elements in different intertidal sediments. The geoaccumulation index method and potential ecological hazard index method were used to evaluate the pollution status of arsenic and mercury in the study area. RESULTS Background value of arsenic content: Minjiang Estuary (2.90mg/kg) < Daliao Estuary (6.42mg/kg) < Yancheng Shoal in northern Jiangsu (11.02mg/kg) < Pearl River Estuary (19.19mg/kg). Background value of mercury content: maximum in Pearl River Estuary (0.08mg/kg), less in Daliao Estuary, Yancheng shoal and Minjiang Estuary (0.02mg/kg, 0.02mg/kg, 0.03mg/kg, respectively). The maximum values of background values of arsenic and mercury were both found in the Pearl River Estuary, and the minimum values were located in the Minjiang Estuary. The maximum values of arsenic and mercury of sediments were both found in the Pearl River Estuary, which were 42.90mg/kg and 0.287mg/kg, respectively, and were greater than the first class of Marine Sediment Quality Standard (arsenic: 20.0mg/kg; mercury: 0.2mg/kg). Arsenic belonged to no pollution and slight potential ecological hazards in the four intertidal sediments. Mercury was a medium potential ecological hazard in the Pearl River Estuary, and slight pollution or no pollution in the other three intertidal sediments. CONCLUSIONS The distribution of arsenic and mercury in the sediments of the four intertidal zones in the study area is characterized by "high in the south and low in the north". The arsenic and mercury contents in the intertidal sediments of Minjiang and Pearl River estuaries are more influenced by industrial and agricultural activities, thus causing the distribution features. The pollution of arsenic and mercury in the Pearl River Estuary is more serious than other intertidal areas, so it is urgent to strengthen the control of their pollution trends.

Oral probiotics meet challenges during processing, storage, and gastrointestinal harsh conditions. Polysaccharide‐based hydrogels delivery system is promising in probiotic protection, but its semi‐solid and weak strength, and often requires additional cross‐links to solidify its structure. Herein a ferric ion co‐crosslinked microgel of Mesona chinensis polysaccharides and mechanically strengthened by phenolic‐metal frameworks of naturally bound brown bioactives is designed. These microgels has an intact structure in acidic condition and ruptured only at pH neutral conditions which can responsively release highly viable probiotics with high mucoadhesion and colonization. Brown bioactives are naturally bound to polysaccharides (MCPC) by hydrophobic interactions and hydrogen bonding, and they exhibited outstanding anti‐inflammatory and antioxidant properties. Moreover, these brown bioactives are the precise prebiotics which can specifically improve the abundance of Akkermansia genus in gut in vivo. Then, the probiotics Akkermansia muciniphila (AKK) are loaded into brown bioactives frameworks strengthened microgels. There is a more synergistic healthy benefit between MCPC components and loaded AKK compared with free and pasteurized AKK. MCPC microgels can deliver high viable AKK specifically to gut consequently modulating the microbiota balance, and protecting the intestinal barriers. MCPC microgels also delivered the antioxidant brown bioactives specifically into liver to alleviate the hepatic oxidative stress and inflammation. [ABSTRACT FROM AUTHOR]

Resveratrol is a kind of plant polyphenols with various bioactivities, which can improve and prevent nonalcoholic fatty liver disease (NAFLD) by reducing oxidative stress and lipid deposition. However, resveratrol is insoluble in water, resulting in low oral bioavailability. In this study, resveratrol was embedded in lysozyme micelles catalyzed by glutamine transaminase. the critical micelle concentration of the carrier was 1.1 g/mL and the particle size was 58 nm, and the drug loading of resveratrol was increased to 21.2%. In the in vitro digestion model, the carrier was resistant to gastric acid and pepsin, and the resveratrol release rate was 61% after the 120 min intestinal digestion. The max concentration of resveratrol in plasma (C„„) was increased to 39.9ng/mL, the area under the curve (AUC0-t8h) was 218.6 ng/ mL, and the absolute bioavailability (Fabs) increased to 3%. The intervention effect of resveratrol on NAFLD was investigated by using NAFLD mouse model. The results showed that the body fat rate of NAFLD mice was 1.1 times lower than that of free resveratrol, and the indexes of blood lipids, triglycerides (TG) and free fatty acids (NEFA) in serum, malondialdehyde (MDA) and superoxide dismutase (SOD) in liver tissue were significantly decreased. The results showed that compared with unembedded resveratrol, resveratrol embedded with lysozyme had a better intervention effect on NAFLD in mice. [ABSTRACT FROM AUTHOR]

This paper studied the 1~3 m thick sedimentary environment in the Laizhou Bay based on the grain size information of 20 core samples. Sand and silty sand are the main components of the sediments in Laizhou Bay, and their sorting degree is poor on the whole, indicating significant influence on the formation of the sediments exerted by surrounding factors. The grain size characteristics of the sediments in Laizhou Bay obviously reflect the environment. The distribution of grain size in cores indicate different stages of forces acting on the sediments in different sea areas. In general, from the coast of Laizhou Bay to the plain under middle shallow sea, the slope of the probability accumulation curve increases gradually and the periodic differentiation becomes more and more distinct. The environmentally sensitive component of Laizhou Bay sediment is 3≤φ≤4, and coastal river properties and sediment transport path have significant effects on grain size and components. Combined with the previous research on sedimentation rate, the periodic changes of grain size and components in the eastern area of Laizhou Bay is temporally corresponding to the diversion of the Yellow River in 1855. The sedimentary environment in the middle sea area of Laizhou Bay has strong hydrodynamics and diverse material sources. The grain size of sediments in Qimudao-Diaolongzui sea area is slightly coarse, requiring a higher critical starting speed and a relatively small probability of resuspension. The Yellow River submerged delta is relatively turbulent with unstable energy. It is in the late stage of gravity flow, with energy attenuation and conversion to traction and drainage. The underwater bank slope in the southern Bay has a certain amount of sedimentation under the action of waves and tidal currents. [ABSTRACT FROM AUTHOR]