Publications by authors named "Zhendong Luan"

Since plastic waste has become a worldwide pollution problem, studying the ability of marine microorganisms to degrade plastic waste is important. However, conventional methods are unable to in situ real-time study the ability of microorganisms to biodegrade plastics. In recent years, Raman spectroscopy has been widely used in the characterization of plastics as well as in the study of biological metabolism due to its low cost, rapidity, label-free, non-destructive, and water-independent features, which provides us with new ideas to address the above limitations.

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Here, we report on progress made in coupling advances in surface-enhanced Raman scattering (SERS) techniques with a deep-ocean deployable Raman spectrometer. Our SERS capability is provided by development of a Cu foam-loaded silver-nanobean (Ag/Cu foam) which we have successfully coupled to the tip of a Raman probe head capable of insertion into deep-sea sediments and associated fluids. Our purpose is to expand the range of molecular species which can be detected in deep-sea biogeochemical environments, and our initial targets are a series of amino acids reportedly found in pore waters of seep locations.

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In recent years, increasing attention has been given to quantifying the isotopic compositions of gases by Raman spectroscopy. However, related research on the carbon isotopes of CH is still lacking. In this study, the Raman spectral characteristics of CH and CH in the pure CH system and in the CH-HO system are comprehensively studied at temperatures ranging from 25 to 400 °C and pressures ranging from 50 to 400 bar.

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Gas production from several metabolic pathways is a necessary process that accompanies the growth and central metabolism of some microorganisms. However, accurate and rapid nondestructive detection of gas production is still challenging. To this end, gas chromatography (GC) is primarily used, which requires sampling and sample preparation.

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The carbon isotopic composition of CO is traced to its different origins and widely used in the fields of geology, biology, and chemistry. Raman spectroscopy can be performed in situ, is nondestructive, and requires no sample preparation; these characteristics enable Raman spectroscopy to be considered a new alternative method to measure the carbon isotopic composition of CO. In this work, Raman spectra of high-purity CO, CO, and six CO-CO binary mixtures with known mixing ratios were collected using a High Pressure Optical Cell (HPOC) at 50-450 °C and 50-400 bar.

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As microbial sulfur metabolism significantly contributes to the formation and cycling of deep-sea sulfur, studying their sulfur metabolism is important for understanding the deep-sea sulfur cycle. However, conventional methods are limited in near real-time studies of bacterial metabolism. Recently, Raman spectroscopy has been widely used in studies on biological metabolism due to its low-cost, rapid, label-free, and nondestructive features, providing us with new approaches to solve the above limitation.

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Zooplankton can affect and regulate the biological carbon pump in the biogeochemical cycles of marine ecosystems through diel vertical migration (DVM) behaviour. The diel vertical distribution and migration of a zooplankton community were studied at a continuous survey station in the Caroline Seamount area of the western tropical Pacific Ocean. Using a MultiNet sampling system, 346 zooplankton species/taxa were collected and identified.

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The anthropogenic and natural impacts on the temporal and spatial variations of heavy metals in sediments under the Shandong Peninsula coastal current are still unclear. Here, the concentrations\burial fluxes of Cr, Cu, Zn, As, and Pb in three sediment cores retrieved from the Bohai Sea and the Yellow Sea along the Shandong Peninsula were analyzed to study the spatial-temporal variability of heavy metal accumulation over the last century. The results showed that the buried heavy metal fluxes were relatively low at the end of the Shandong Peninsula coastal current.

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The chlorinity of deep-sea hydrothermal fluids, representing one of the crucial deep-sea hydrothermal indicators, indicates the degree of deep phase separation of hydrothermal fluids and water/rock reactions. However, accurately measuring the chlorinity of high-temperature hydrothermal fluids is still a significant challenge. In this paper, a piecewise chlorinity model to measure the chlorinity of high-temperature hydrothermal fluids was developed based on the OH stretching band of water, exhibiting an accuracy of 96.

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Supercritical CO appearing as bubbles in hydrothermal vents was identified in the south part of the Okinawa Trough using in situ Raman spectroscopy. Significantly, the N peak in supercritical CO is much larger than those in seawater and vent fluids, indicating that supercritical CO enriches N from the surrounding environment. Considering that the partial pressures of CO and N in the Earth's proto-atmosphere were ~10-20 MPa, supercritical CO with high N was likely the dominant CO phase near the water-air interface in the early history of the Earth, which promoted the synthesis, pre-enrichment and preservation of amino acids and other organic matters that are essential to the origin of life.

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In this study, we report a novel Gram-negative bacterium, designated as strain CS412, isolated from deep-sea sediment collected in a cold seep area of the South China Sea. Growth of strain CS412 occurred at 4-40 °C (optimum, 28 °C), pH 5.0-11.

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Thermophiles are organisms that grow optimally at 50 °C-80 °C and studies on the survival mechanisms of thermophiles have drawn great attention. Bacillus manusensis S50-6 is the type strain of a new thermophilic species isolated from hydrothermal vent in Manus Basin. In this study, we examined the growth and global responses of S50-6 to high temperature on molecular level using multi-omics method (genomics, proteomics, and metabolomics).

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The OH stretching band of water is very sensitive to temperature and salinity for the existence of hydrogen bonds between HO molecules. In this study, the OH stretching band was deconvoluted into two Gaussian peaks, with peak 1 at approximately 3450 cm and peak 2 at approximately 3200 cm. The positions of peaks 1 and 2 both shifted to higher wavenumbers with increasing temperature from 50 ℃ to 300 ℃.

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Raman spectroscopy has been applied to the quantitative analysis of the concentration of bisulfate in acid-sulfate fluids at different temperatures. The quantitative analysis method is based on the peak area ratios of [Formula: see text](ν) and HO (ν), where PA([Formula: see text]/HO) = [[Formula: see text]] × (0.0066 × T + 1.

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Two Gram-staining-positive, strictly aerobic bacilli, designated as strains Ma50-5 and Ma50-6, were isolated from the hydrothermal sediments of Manus Basin in the western Pacific Ocean. Based on 16S rRNA gene sequence, strains Ma50-5 and Ma50-6 were most closely related to Bacillus alveayuensis (97.0 and 97.

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Deep-sea carbon dioxide (CO) plays a significant role in the global carbon cycle and directly affects the living environment of marine organisms. In situ Raman detection technology is an effective approach to study the behavior of deep-sea CO. However, the Raman spectral characteristics of CO can be affected by the environment, thus restricting the phase identification and quantitative analysis of CO.

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Shrimp of the family Alvinocarididae are the predominant megafauna of deep-sea hydrothermal vents. However, genome information on this family is currently unavailable. In the present study, by employing Illumina sequencing, we performed the first de novo transcriptome analysis of the gills of the shrimp Rimicaris sp.

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