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The carbon cycle in soil is significantly influenced by soil microbes. To investigate the vertical distribution of the dominant groups in agricultural soil and the carbon metabolic diversity of soil bacteria, 45 soil samples from the 0 ~ 50 cm soil layer in Hunan tobacco–rice multiple cropping farmland were collected in November 2017, and the carbon diversity of the soil bacterial community, bacterial community composition and soil physical and chemical properties were determined. The results showed that the carbon metabolic capabilities and functional diversity of the soil bacterial community decreased with depth. The three most widely used carbon sources for soil bacteria were carbohydrates, amino acids, and polymers. The dominant bacterial groups in surface soil (such as Chloroflexi, Acidobacteriota, and Bacteroidota) were significantly positively correlated with the carbon metabolism intensity. The alkali-hydrolysable nitrogen content, soil bulk density and carbon–nitrogen ratio were the key soil factors driving the differences in carbon metabolism of the soil bacterial communities in the different soil layers.

PurposeWe purified and characterized a novel ene-reductase (KaDBR1) from Kazachstania exigua HSC6 for the synthesis of dihydro-β-ionone from β-ionone.MethodsKaDBR1 was purified to homogeneity by ammonium sulfate precipitation and phenyl-Sepharose Fast Flow and Q-Sepharose chromatography. The purified enzyme was characterized by measuring the amount of dihydro-β-ionone from β-ionone with LC–MS analysis method.ResultsThe molecular mass of KaDBR1 was estimated to be 45 kDa by SDS-PAGE. The purified KaDBR1 enzyme had optimal activity at 60 °C and pH 6.0. The addition of 5 mM Mg2+, Ca2+, Al3+, Na+, and dithiothreitol increased the activity of KaDBR1 by 25%, 18%, 34%, 20%, and 23%, respectively. KaDBR1 favored NADH over NADPH as a cofactor, and its catalytic efficiency (kcat/Km) toward β-ionone using NADH was 8.1-fold greater than when using NADPH.ConclusionOwing to its unique properties, KaDBR1 is a potential candidate for the enzymatic biotransformation of β-ionone to dihydro-β-ionone in biotechnology applications.

Crustaceans play an important role in marine ecosystem and worldwide fisheries. Accurate and quantitative description of growth is crucial in modelling the demographics and fisheries stock assessment. The stepwise growth as a result of the moulting process and the lack of permanent calcified structures make the traditional approaches developed for finfish inappropriate for crustaceans. This study reviews the data collection, quantitative methods and various sources of uncertainty for modelling the growth of crustacean. The methods were reviewed based on their data requirement and mathematical/statistical complexity ranging from simple growth rate, continuous growth curve to stepwise growth curve and size transition matrix. A comparative example of different growth models was illustrated with four selected crustaceans: American lobster ( Homarus americanus , Nephropidae), Dungeness crab ( Metacarcinus magister , Cancridae), blue crab ( Callinectes sapidus , Portunidae) and pronghorn spiny lobster ( Panulirus penicillatus , Palinuridae). Model selection and multi-model inference based on the information theory was discussed for modelling the growth components of moutling increment and intermoult period. Various drivers in determination of the growth pattern of crustaceans were evaluated, including life history strategy and environmental stress. The incorporation of environmental factors into the development of growth models and the recent progress in age-determination were highlighted. We discussed possible research needs for better quantification of crustaceans growth.

To characterize a novel thermophilic β-carotene 15,15′-monooxygenase BCMO7211 isolated from the marine bacterium Candidatus Pelagibacter sp. HTCC7211. BCMO7211 was functionally overexpressed in Escherichia coli and purified to homogeneity by Ni–NTA affinity chromatography and Superdex-200 gel filtration chromatography. Labeling experiments with H218O demonstrated that the oxygen atom in the terminal aldehyde group of the produced retinal molecules was provided from both molecular oxygen and water, indicating that BCMO7211 is the first characterized bacterial β-carotene 15,15′-monooxygenase. BCMO7211 exhibited broad carotenoid substrate specificity toward α-carotene, β-cryptoxanthin, β-carotene, zeaxanthin, and lutein. The optimum temperature, pH, and concentrations of the substrate and enzyme for retinal production were 60 °C, 9.0, 500 mg β-carotene/L, and 2.5 U/ml, respectively. Under optimum conditions, 888.3 mg/L retinal was produced in 60 min with a conversion rate of 89.0% (w/w). BCMO7211 is a potential candidate for the enzymatic synthesis of retinal in biotechnological applications.

Striped Marlin is a highly migratory species distributed throughout tropical and temperate waters in the North Pacific Ocean. The habitat characteristics of Striped Marlin in the western and central North Pacific Ocean were examined using generalized additive models by modelling fishery catch-rates as a function of remotely-sensed environmental covariates, including sea surface temperature (SST), chlorophyll-a concentration (CHL), mixed layer depth (MLD) and sea height anomalies (SHA). SST explained the largest proportion of the deviance, and is therefore considered the best predictor for the habitat of Striped Marlin. Spatial distributions of the relative density of Striped Marlin indicated that there is a seasonal north–south migration, and that the highest densities occur in the central North Pacific Ocean. The preferred habitat characteristics of Striped Marlin in high density areas were identified as SST between 23 and 26 °C, MLD within 30 m depth, and CHL around 0.08 mg m⁻³, while no preferred range was found for SHA. The results of this study could improve our understanding of Striped Marlin spatial distributions and habitat characteristics.

The reproductive biology of spiny lobster, Panulirus penicillatus, was studied based on 2,068 lobsters, ranging from 34.28 to 131.60 mm carapace length (CL), sampled in Taitung coastal waters from September 2003 to December 2004. The overall sex ratio approximated 1:1 (χ² = 0.02, P > 0.05), but the monthly sex ratios in 2004 showed significant differences and males were predominant in sizes larger than 80 mm CL. Reproductive activity, assessed using histology, a gonadosomatic index and percentage of ovigerous females, indicated that the mature females could be found in every month and that the major spawning occurred from May to September. The presence of re-developing/re-ripe ovaries by month and size-specific spawning time suggest that larger mature females (>60 mm CL) spawn at least three times a year while smaller new mature females spawn at least once a year. For females, the estimated sizes at 50% physiological and functional maturity were (mean ± SE) 56.46 ± 0.56 mm CL and 66.63 ± 1.07 mm CL. The estimated sizes at functional maturity were between 72 and 74 mm CL for males. The number of eggs per spawning event (brood size, BS) was related to CL by the equation Y BS = 2.4 × 10⁻³CL⁴.¹⁸ (r ² = 0.902, n = 12). Female lobsters with CL ranging from 60 to 80 mm made the greatest contributions to egg production because of their high brood size and active reproductive activity. A minimum legal size should be established for the fishery to protect egg production potential of lobster population in the southeastern coastal waters off Taiwan.

Slow pyrolysis (SP) and fast pyrolysis (FP) of rice husks, coconut shells and their mixtures were studied in a fixed bed reactor. The objectives of this study were to compare the yields and properties of bio-oils produced using SP and FP methods within a pyrolysis temperature range of 400 °C to 600 °C. Three different biomass compositions, 100% rice husks (RH), 100% coconut shells (CS) and a mixture of 50% rice husks with 50% of coconut shells (RH50/CS50) were experimented. In SP, the maximum yield of bio-oil for RH, CS and RH50/CS50 were 45.45%, 37.01%, 38.29% at temperatures of 550 °C, 500 °C and 600 °C respectively. As for FP, the maximum bio-oil yield obtained for RH, CS and RH50/CS50 were 50.52%, 40.14% and 42.25% at temperatures of 500 °C, 600 °C and 550 °C respectively. At these optimum pyrolysis temperatures, the percentage differences in bio oil yields for SP and FP were 10.57%, 8.11% and 9.83% for RH, CS and RH50/CS50 respectively. Based on American Society for Testing and Materials (ASTM) standard procedures, the properties of bio-oil were characterised and it was found that the bio oil produced by FP at optimum temperatures were less acidic, higher density, lower water content and viscosity as compared to the bio-oil produced by SP method for all biomass compositions.

3-Hydroxy-β-ionone, a flavor and fragrance compound with fruity violet-like characteristics, is widely applied in foodstuff and beverages, and is currently produced using synthetic chemistry. In this study, a novel lutein cleavage enzyme (EhLCD) was purified and characterized from Enterobacter hormaechei YT-3 to convert lutein to 3-hydroxy-β-ionone. Enzyme EhLCD was purified to homogeneity by ammonium sulfate precipitation, Q-Sepharose, phenyl-Sepharose, and Superdex 200 chromatography. The molecular mass of purified EhLCD, obtained by SDS-PAGE, was approximately 50 kDa. The enzyme exhibited the highest activity toward lutein, followed by zeaxanthin, β-cryptoxanthin, and β-carotene, suggesting that EhLCD exhibited higher catalytic efficiency for carotenoid substrates bearing 3-hydroxy-ionone rings. Isotope-labeling experiments showed that EhLCD incorporated oxygen from O2 into 3-hydroxy-β-ionone and followed a dioxygenase reaction mechanism for different carotenoid substrates. These results indicated that EhLCD is the first characterized bacterial lutein cleavage dioxygenase. Active EhLCD was also confirmed to be a Fe2+-dependent protein with 1 molar equivalent of non-haem Fe2+. The purified enzyme displayed optimal activity at 45 °C and pH 8.0. The optimum concentrations of the substrate, enzyme, and Tween 40 for 3-hydroxy-β-ionone production were 60 μM lutein/L, 1.5 U/mL, and 2% (w/v), respectively. Under optimum conditions, EhLCD produced 3-hydroxy-β-ionone (637.2 mg/L) in 60 min with a conversion of 87.0% (w/w), indicating that this enzyme is a potential candidate for the enzymatic synthesis of 3-hydroxy-β-ionone in biotechnological applications.

[Purpose/Significance] This paper compares the characteristics of \"marine aquatic feed\" technology evolution in different countries based on the global patent data in order to find out the international situation and problems China is faced with in China's innovation development. [Method/Process] Using bibliometric analysis of patent literature, this paper analyzes the patents development trend, distribution trend, patent competitiveness, patentee's characteristics, and patent technology development of international \"marine aquatic feed\" field. [Results/Conclusions] The results show that the patented technology of \"marine aquatic feed\" is being transferred to emerging markets, and refined and breakthrough technology research is the development direction in the future. In recent ten years, China's patents show a strong growth trend, but the development of China's patent portfolio and market inflow in the world is not optimistic. There is a mismatch between the growth of patents quantity and the quality, patents protection and cooperation is on the low side, and patents market application is insufficient. In the future, the high quality development and application of \"marine aquatic feed\" technology should be continuously promoted from such aspects as enhancing policy guidance and support, tracking international technology and market trends, strengthening \"industry-university-research\" cooperation and improving patent quality.

On Jan.31 of 2010,the Suining earthquake occurred at Suining City whch is located the center of Sichuan Basin.It is unusual for the strong earthquake to occur at the center of Sichuan Basin with a stable geotectonic environment and a low-level historical seismicity.The macro-epicenter of the earthquake is located at Moxi town of Suining city,Sichuan province,China.The earthquake intensity of the epicenter area is degree VII,and the long axis of the isoseismal line trends in NE orientation.The Suining earthquake caused the collapse or destruction of 460 family houses.The earthquake focal mechanism solution and records of the near-field seismographic stations showed the earthquake occurred at the reverse fault at a depth 34 km.Based on the waveform and focal mechanism,we consider the Suning earthquake is triggered by the reverse fault and not by the gravitational collapse or man-made explosive sources.Basing on seismic refraction profile and borehole,we consider that the earthquake is triggered by the backthrust fault of Moxi anticline rooted in detachments at a depth 3-4 km.Furthermore,we infer that tectonic mechanism of the Suining（Ms5.0） Earthquake is driven by the horizontal crustal shortening and stress adjustment on a shallow detachment after the Wenchuan（Ms 8.0） earthquake.