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Increasing attention has recently been focused on complex symbiotic associations, for instance coral and its symbionts. Sea cucumber, harboring diverse fungi, has also attracted more and more attention for their functional diversity. Here, secondary metabolites produced by Chaetomium globosum associated with sea cucumber, Apostichopus japonicus, were investigated using gene mining with third-generation sequencing technology (PacBio SMRT). Nine compounds, including one new compound cytoglobosin X (1), were isolated from cultures of Chaetomium globosum. Compound 1 was identified based on NMR data, HRESIMS, and ECD, and the absolute configurations were identified as 3S, 4R, 7S, 8R, 9R, 16S, 19S, 20S, and 23S. In an antimicrobial assay, compound 4 showed moderate activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus with MICs of 47.3 and 94.6 μM, respectively. Our results suggest that the microbiomes associated with sea cucumber could be an important resource for biodiversity and structural novelty, and the bioactive compounds may protect the host from pathogen microbial.

Xihu Depression is a relatively new petroleum exploration area in East China Sea Basin. Pinghu Formation is one of the most important oil-bearing formations in the depression. Due to the low exploration level of the depression, paleosalinity and deposition environment of the depression in Pinghu stage is not clear. Element geochemical analysis of samples from different structural units is used to study ancient water salinity and reveal the depositional environment. B/Ga ratio, which is sensitive to paleosalinity in study area, is 0.9–4.0 and indicates characteristics of mixed water of fresh and salt water. There is a threshold for Sr/Ba in water salinity study in the study area. When Sr/Ba ratio is lower than 0.15, it cannot be used as an indicator for salinity and ancient water body type. Equivalent boron content calculated by Walker's method is lower than 150 ppm. Paleo salinity from boron content calculated by Couch's method is 2.97‰–9.61‰ and the average is 4.8‰. Based on the above mentioned results, ancient water body of Xihu Depression in Pinghu stage has typical characteristics of brackish water and it belongs to oligohaline and mesohaline water. Combining paleogeomorphology and sedimentary facies distribution in the study area, paleowater body in Xihu Depression during Pinghu stage is transitional mixed water influenced by terrigenous diluted water. Paleosalinity contour lines extend on plane from north to the south and are parallel to paleo-coastline. Paleosalinity increases from the west to the east. Influenced by freshwater of deltas at western part of the depression, high abnormal salinity values occur around the wells M1 and L1 where salinity contour lines curve westward.

Conventional epoxy asphalt and its mixtures have a complex application procedure that leads to poor stability, easy segregation, and strict on-the-spot preparation requirements and applications. To solve these issues, the performance of a mixture of a customized dry-method-epoxy modifier and its asphalt mixture was evaluated. Functional groups before and after curing were analyzed using Fourier transform infrared spectrometry; the curing behavior was analyzed by non-isothermal differential scanning calorimetry tests; an optical microscope was used to observe the dispersibility of the dry-method-epoxy modifier in the asphalt, determine the optimal mixing ratio of the dry-method-epoxy modifier and the asphalt through the dispersibility, and observe the curing state. The relationship between the factors influencing the construction and road performance of dry-method-epoxy-asphalt mixture was evaluated using an orthogonal test and the Gray situation-decision method. The performance of the mixture under optimized conditions was then examined, and the results indicate that our modifier was exposed to a completed reaction at high temperatures. The curing heat decreased with increase in heating rate, resulting in a reduced reaction degree. The calculations demonstrated that the curing of dry-method-epoxy modifier is an approximately first-order reaction, although the reaction exotherm is concentrated and its tendency is high. Moreover, orthogonal tests were used to formulate 16 test plans for five factors and four levels of dry-method-epoxy asphalt mixture. The optimized conditions determined through the orthogonal test and the Gray situation-decision method were gradation = EA10, oil–stone ratio = 4.5, curing temperature = 150 °C, curing time = 4 h, and retention time = 30 min. Considering the realistic factors, an optimized scheme was determined and applied to assess the road performance of dry-method-epoxy-asphalt mixture. Based on the test, the Marshall stability was up to 65.28 kN, the dynamic stabilities at 60 °C and 70 °C were 43,200 and 27,391 times mm−1, respectively, the freeze–thaw-splitting-strength ratio was 109%, the residual water-stability ratio was 96.2%, and the low temperature bending maximum flexural-tension strain was 3562 μe. This study confirmed the performance of dry-method-epoxy modifier and its mixtures with asphalt, thus providing theoretical guidance for practical applications.