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Chromium isotopes are promising for monitoring and quantifying the extent of microbial Cr(VI) reduction. However, the mechanisms and factors that influence Cr isotope fractionation are not well understood. In the present study, we investigated the effects of different metabolic pathways and various environmental parameters on Cr isotope fractionation during Cr(VI) reduction by the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus. The Cr isotopic compositions were measured on unreacted Cr(VI) in the remaining solution. The reaction product is isotopically lighter than the reactant. The Cr isotope composition for remaining Cr(VI) in the solution followed a Rayleigh fractionation trend and thus became increasingly isotopically heavier as the reduction of Cr(VI) proceeded. Cr(VI) reduction mainly occurs on the cell surface by Ni–Fe hydrogenase; however, in the presence of CuCl 2 , the activity of Ni–Fe hydrogenase was inhibited, and Cr(VI) was reduced inside the cells. We found that despite different Cr(VI) reduction locations, Cr isotope enrichment factors (ε = (α − 1) × 1000, where α is the fractionation factor) were identical within uncertainty for experiments with and without CuCl 2 (−2.72 ± 0.67‰ and −2.92 ± 0.14‰, respectively). When added to the cell cultures, neutral red (NR) functioned as an electron carrier that enabled bacteria to drive the electron transfer processes. The ε values were also similar for experiments with and without NR (−2.53 ± 0.40‰ and −2.92 ± 0.14‰, respectively). We compared these ε values to investigate the effects of different electron transport pathways and cellular Cr(VI) transfer processes, including Cr(VI) transport across the cell envelope and binding to reacting enzymes, on Cr isotope fractionation. Furthermore, the effects of various environmental parameters on Cr isotope fractionation were tested, including temperature (50 °C and 70 °C), hydrogen concentration, and different electron donors (glucose and hydrogen). The ε values were similar at both tested temperatures and stayed within the previously observed range for mesophiles; changes in hydrogen concentration also did not affect the ε values. However, the ε values were slightly higher with hydrogen as the electron donor (−3.64 ± 0.24‰) than those with glucose as the electron donor (−2.92 ± 0.14‰). In short, the Cr enrichment factors remained unchanged despite of changing microbial Cr (VI) reduction pathways and changing temperature conditions, but may be sensitive to the electron donor type. [ABSTRACT FROM AUTHOR]

Modified starch was better suitable for food processing, and fermentation was one of the effective methods to modify starch. This study investigated the separate and synergistic fermentation of Lactiplantibacillus plantarum and Saccharomyces cerevisiae could whether affect the multi-scale structure and physicochemical properties of highland barley starch (HBS). The results of multi-scale structure determination of HBS showed that compared with unfermented HBS (32.27%), fermentation showed a significant increase in relative crystallinity (35.49–39.81%), while the crystal type of HBS as observed from X-ray diffraction (A-type crystalline pattern) did not change. The small angle X-ray scattering revealed that fermentation reduced the amorphous region and increased the crystalline layer thickness of the HBS. Consequently, the changes in the physicochemical properties showed that the peak viscosity, trough viscosity, and final viscosity of HBS were reduced after fermentation, and the aging of starch gel was delayed significantly. Our results showed that Lactiplantibacillus plantarum and Saccharomyces cerevisi ae fermentations improve the physicochemical properties of HBS by modifying the multi-scale structure of starch, especially the synergistic fermentation effect was more effective. [Display omitted] • The multi-scale structure of highland barley starch changed obviously during fermentation. • Fermentation reduced the hardness and viscosity of highland barley starch and the aging of starch gel was delayed. • Lactiplantibacillus plantarum and Saccharomyces cerevisiae fermentation was an effective method for starch modification. [ABSTRACT FROM AUTHOR]

The global ongoing increase in the atmospheric CO 2 concentration is a gradual rather than an abrupt process. Although the abrupt increase in atmospheric CO 2 concentration has been reported to greatly affect nitrite-dependent anaerobic methane oxidation (n-damo), the effect of a gradual increase in atmospheric CO 2 concentration on n-damo remains unclear. To better evaluate the role of n-damo in paddy soils, this study investigated the responses of n-damo to different CO 2 treatments: the ambient CO 2 concentration (CK), a gradual increase (GI), and an abrupt increase (AI) in the CO 2 concentration across different growth periods and soil depths. The 13CH 4 stable isotope and quantitative PCR results revealed that compared to the CK, GI and AI significantly increased the activity of n-damo by 91.6 % and 90.0 % (p < 0.05), respectively, and also significantly increased the abundance of Candidatus Methylomirabilis oxyfera (M. oxyfera)-like bacteria by 67.7 % and 98.6 % (p < 0.05), respectively. Although there was no significant variation between GI and AI. In addition, the activity and abundance differed significantly between growth period and soil depth. The high-throughput sequencing results showed that GI and AI had little effect on bacterial community, while the soil depth had a significant impact on bacterial community. The changes in several soil physiochemical factors (e.g., the contents of soil water, organic carbon, and inorganic nitrogen) had important impacts on n-damo activity and the bacterial community structure. Overall, the results indicate a positive and similar response of n-damo to both gradual and abrupt increases in the atmospheric CO 2 concentration in paddy soils. [Display omitted] • The eCO 2 significantly increased n-damo activity. • The eCO 2 significantly increased M. oxyfera -like bacterial abundance. • The response of n-damo to GI and AI treatments had no significant difference. • Rice growth periods and soil depths had significant effects on n-damo. [ABSTRACT FROM AUTHOR]

[Display omitted] • R -FW nutrient removal reached 72.44–86.63% by C. pyrenoidosa under batch mode. • R -FW nutrient removal boosted 94.70–99.79% by C. pyrenoidosa under fed-batch mode. • R -FW feeding Chlorella gave abundant amino acid profiles and high-quality protein. • Pathogenic bacteria and heavy metal load in R -FW Chlorella matched fodder standard. • In vitro digestion/bioavailability of R -FW Chlorella was equivalent to corn/soybean. The scenario was to investigate feasibilities of employing Chlorella pyrenoidosa for Rhizopus oryzae fermentation wastewater nutrient removal coupling protein fodder production. Results stated that TN, TP, NH 3 -N, COD, BOD removal reached 99.79%, 94.70%, 98.80%, 97.60%, 99.60% to acquire discharge permit under fed-batch manipulation, whilst the peaked protein yield (19.94 g/L) was 6.04-fold more than batch manipulation. Rhizopus oryzae fermentation wastewater feeding C. pyrenoidosa was praised as high-quality protein not only with 26.78% essential amino acids and essential amino acids/nonessential amino acids value of 0.84 but also pathogenic bacteria and heavy metal loads complying with fodder standards. In vitro digestibility of dry matter, protein, lipid, and starch achieving 80.07%, 92.13%, 95.93%, 91.9% and bioavailability of polypeptides, triglycerides, free fatty acids, and oligosaccharides displaying 98.67%, 87.12%, 93.86%, 30.21%, which were roughly-equivalent to corn/soybean fodder. The findings formed exemplifications in utilizing other microalgal systems for wastewater nutrient removal coupling chemicals production. [ABSTRACT FROM AUTHOR]

Emerging evidence indicates that extracellular vesicle (EV) long non-coding ribonucleic acids (lncRNAs) in lung cancer may be clinically useful biomarkers for early diagnosis using liquid biopsy. However, the extremely low quantities of EV-lncRNAs in peripheral blood are a major challenge for multi-target detection. In this study, we developed a new multi-colour fluorescence digital PCR EV-lncRNA (miDER) analysis chip, and then demonstrated its ability to quickly and accurately analyse the levels of two target genes and one reference gene from peripheral blood. Under the miDER assay, the limit of detection of the target gene from peripheral blood was 10 copies/μL. Based on multiplex assay, the expression levels of two lung cancer-related genes (SLC9A3-AS1 and PCAT6) in patients with lung cancer (n = 32) and healthy controls (n = 30) showed a significant difference between the two groups (P < 0.001; two-tailed t -test). A receiver operating characteristic (ROC) curve analysis was used to evaluate the discrimination ability of these lncRNAs. The combination of two lncRNAs in the miDER assay yielded a higher area under curve (AUC) value of 0.811 (95% CI = 0.705–0.918). Moreover, to determine the absolute quantitation capacity of the miDER assay, we compared the results to those obtained by quantitative real-time polymerase chain reaction (qPCR), demonstrating that the miDER assay is more sensitive than qPCR. The multiplex assay based on the miDER could provide a new solution for the multi-index combined detection of trace EV-lncRNAs in body fluids and demonstrate the use of EV-lncRNAs as biomarkers for lung tumour biopsy. • A new multi-colour fluorescence digital PCR EV-lncRNA (miDER) analysis chip was developed. • The miDER system can simultaneously detect multi-target EV-lncRNAs. • The clinical blood samples were analysed and showed the potential of EV-lncRNAs as a candidate marker for lung cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] • The absorption of dietary free CML in the body was higher than that of BSA-CML. • Jejunum accumulated a higher amount of free CML among the intestinal tissues measured. • Kidneys were the target organ for the uptake of absorbed free CML. • Urinary and fecal excretion after oral intake of free CML were lower than that of BSA-CML. As a representative product of advanced glycation end products, Nɛ-carboxymethyllysine (CML) exists in free and bound forms in vivo and in food with different bioavailability. To thoroughly understand the bioavailability of free Nɛ-carboxymethyllysine (CML) and bovine serum albumin (BSA)-CML in vivo after intragastric administration, pharmacokinetics, biodistribution, and excretion of CML in rats were investigated by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Pharmacokinetics results revealed that free CML peaked at 1.83 h (1684.72 ± 78.08 ng/mL) and 1.33 h (1440.84 ± 72.48 ng/mL) in serum after intragastric administration of free CML and BSA-CML, demonstrating the higher absorption of free CML than BSA-CML. Besides, dietary free CML exhibited a relatively lower body clearance and tissue distribution than dietary BSA-CML based on the apparent volume of distribution and body clearance. Moreover, free CML was concentrated in the kidneys, indicating that kidneys were the target organ for the uptake of absorbed free CML. Additionally, the total excretion rate of CML in urine and feces were 37% and 60% after oral administration of free CML and BSA-CML. These results shed pivotal light on a better understanding of the biological effects of free and bound CML on health. [ABSTRACT FROM AUTHOR]

Abstract: The production of ligninolytic enzymes and protease by Phanerochaete chrysosporium was investigated under different culture conditions. Different amounts of medium were employed in free and immobilized culture, together with two kinds of medium with different C/N ratios. Little lignin peroxidase (LiP) (< 2U/L) was detected in free culture with nitrogen-limited medium (C/N ratio: 56/2.2, in mmol/L), while manganese peroxidase (MnP) maximum activity was 231 and 240 U/L in 50 and 100 ml medium culture, respectively. Immobilized culture with 50 ml nitrogen-limited medium gave the highest MnP and LiP production with the maximum values of 410 and 721 U/L separately on the day 5; however, flasks containing 100 ml nitrogen-limited medium only produced less MnP with a peak value of 290 U/L. Comparatively, carbon-limited medium (C/N ratio: 28/44, in mmol/L) was adopted in culture but produced little MnP and LiP. Medium type had the greatest impact on protease production. Large amount of protease was produced due to glucose limitation. Culture type and medium volume influence protease activity corporately by affecting oxygen supply. The results implied shallow immobilized culture was a possible way to gain high production of ligninolytic enzymes. [Copyright &y& Elsevier]

Nitrite-driven anaerobic oxidation of methane (nitrite-driven AOM), mediated by ' Candidatus Methylomirabilis oxyfera' (M. oxyfera)-related bacteria, is a newly-discovered CH 4 consumption process in coastal wetlands. Although Spartina alterniflora invasion significantly affects CH 4 emissions from coastal wetlands, its impact on the nitrite-driven AOM process and the underlying mechanisms remain unknown. Here, we examined nitrite-driven AOM activity and M. oxyfera -related bacterial community in four coastal wetlands along the southeastern coast of China, under invasive Spartina alterniflora and native plants, including Kandelia candel , Avicennia marina or Phragmites australis. Linear mixed-effects models indicated that the Spartina alterniflora invasion stimulated the overall nitrite-driven AOM activity by an average of 61.5% in coastal wetlands (p < 0.05), but had no impact on the M. oxyfera -related bacterial abundance (p > 0.05). The nitrite-driven AOM activity was 7.1 times higher under Spartina alterniflora than under native species in Yueqing Bay (p < 0.05), and was 34.7%, 8.9% and 15.1% higher under Spartina alterniflora than under native species in Hengsha Island, Jiulong River and Zhanjiang, respectively (p > 0.05). Spartina alterniflora invasion increased the bacterial abundance in Yueqing Bay and Jiulong River Estuary by 6.8 and 7.6 times, respectively, while decreased the abundance by 34.4% and 51.4%, respectively, in Hengsha Island and Zhanjiang (p > 0.05). The partial least squares path model indicated an indirect impact of Spartina alterniflora invasion on the nitrite-driven AOM activity through its effect on soil properties, primarily including dissolved organic carbon content and nitrate content. The Spartina alterniflora invasion did not greatly alter M. oxyfera -related bacterial community. Overall, we shed new light on the potential impact of Spartina alterniflora invasion on CH 4 cycling in coastal wetlands. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Lung adenocarcinoma has one of the poorest outcomes of any cancer worldwide, in part due to the lack of a reliable means of early detection. Long noncoding RNAs (lncRNAs) have been shown to be deregulated in some types of cancer; however, the contributions of lncRNAs to lung adenocarcinoma remain unknown. Methods We described the expression profile of lncRNAs in human lung adenocarcinoma at an early stage and the corresponding adjacent nontumorous tissues (NT) by microarray. From the microarray analysis, a total of 1170 lncRNAs were significantly differentially expressed in three early stage lung adenocarcinoma tissues compared with NT (fold-change ≥ 2.0, p ≤ 0.05). Candidate biomarkers were selected from the significantly differentially expressed lncRNAs based on our established filtering pipeline; subsequently, marker optimization and validation by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) on a total of 102 pairs of early stage lung adenocarcinoma and NT samples. Results A panel of 5-lncRNA was identified that could distinguish early stage lung adenocarcinoma from NT samples with high sensitivity and specificity. The area under the receiver operating characteristic curve (AUC) for tumor identification in the training and validation sets were 0.978 and 0.987, respectively. Conclusions Our results are the first to reveal differentially expressed lncRNAs in early stage lung adenocarcinoma and suggest that lncRNAs may be novel candidate biomarkers for the early detection of this disease. [ABSTRACT FROM AUTHOR]