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The purpose of this study is to evaluate the decolorization ability and detoxification effect of LAC-4 laccase on various types of single and mixed dyes, and lay a good foundation for better application of laccase in the efficient treatment of dye pollutants. The reaction system of the LAC-4 decolorizing single dyes (azo, anthraquinone, triphenylmethane, and indigo dyes, 17 dyes in total) were established. To explore the decolorization effect of the dye mixture by LAC-4, two dyes of the same type or different types were mixed at the same concentration (100 mg/L) in the reaction system containing 0.5 U laccase, and time-course decolorization were performed on the dye mixture. The combined dye mixtures consisted of azo + azo, azo + anthraquinone, azo + indigo, azo + triphenylmethane, indigo + triphenylmethane, and triphenylmethane + triphenylmethane. The results obtained in this study were as follows. Under optimal conditions of 30 °C and pH 5.0, LAC-4 (0.5 U) can efficiently decolorize four different types of dyes. The 24-hour decolorization efficiencies of LAC-4 for 800 mg/L Orange G and Acid Orange 7 (azo), Remazol Brilliant Blue R (anthraquinone), Bromophenol Blue and Methyl Green (triphenylmethane), and Indigo Carmine (indigo) were 75.94%, 93.30%, 96.56%, 99.94%, 96.37%, and 37.23%, respectively. LAC-4 could also efficiently decolorize mixed dyes with different structures. LAC-4 can achieve a decolorization efficiency of over 80% for various dye mixtures such as Orange G + Indigo Carmine (100 mg/L+100 mg/L), Reactive Orange 16 + Methyl Green (100 mg/L+100 mg/L), and Remazol Brilliant Blue R + Methyl Green (100 mg/L+100 mg/L). During the decolorization process of the mixed dyes by laccase, four different interaction relationships were observed between the dyes. Decolorization efficiencies and rates of the dyes that were difficult to be degraded by laccase could be greatly improved when mixed with other dyes. Degradable dyes could greatly enhance the ability of LAC-4 to decolorize extremely difficult-to-degrade dyes. It was also found that the decolorization efficiencies of the two dyes significantly increased after mixing. The possible mechanisms underlying the different interaction relationships were further discussed. Free, but not immobilized, LAC-4 showed a strong continuous batch decolorization ability for single dyes, two-dye mixtures, and four-dye mixtures with different structures. LAC-4 exhibited high stability, sustainable degradability, and good reusability in the continuous batch decolorization. The LAC-4-catalyzed decolorization markedly reduced or fully abolished the toxic effects of single dyes (azo, anthraquinone, and indigo dye) and mix dyes (nine dye mixtures containing four structural types of dyes) on plants. Our findings indicated that LAC-4 laccase had significant potential for use in bioremediation due to its efficient degradation and detoxification of single and mixed dyes with different structural types. • LAC-4 laccase had strong decolorization abilities for four main types of dyes • Four different interaction relationships in the decolorization of dye mixtures by laccase were found • The decolorization effects of the dyes that were very difficult to be degraded greatly improved when mixed with other dyes • Free, but not immobilized, LAC-4 laccase showed a strong continuous batch decolorization ability for single and mixed dyes • LAC-4 treatment could eliminate or reduce the phytotoxicity of single dyes and mixed dyes [ABSTRACT FROM AUTHOR]

Abstract The interaction between pure culture microorganisms has been evaluated allowing for the enhanced biodegradation of various kinds of pollutants. Arthrobacter sp. DNS10 previously enriched in an atrazine-containing soil was capable of utilizing atrazine as the sole nitrogen source for growth, and Enterobacter sp. P1 is a phosphorus-solubilizing bacterium that releases various kinds of organic acids but lacks the ability to degrade atrazine. Whether strain P1 could enhance atrazine biodegradation by the degrader strain DNS10 was investigated in this experiment. Gas chromatography and high-performance liquid chromatography results showed that co-culture of both strains degraded 99.18 ± 1.00% of the atrazine (initial concentration was 100 mg L−1), while the single strain DNS10 only degraded 38.57 ± 7.39% after a 48 h culture, and the resulting concentration of the atrazine final metabolite cyanuric acid were 63.91 ± 3.34 mg L−1 and 26.60 ± 3.87 mg L−1, respectively. In addition, the expression of the atrazine degradation-related genes trz N, atz B and atz C in co-culture treatments was 6.61, 1.81 and 3.09 times that of the single strain DNS10 culture treatment. A substrates utilization test showed that the atrazine-degrading metabolites ethylamine and isopropylamine could serve as the nitrogen source to support strain P1 growth, although strain P1 cannot degrade atrazine or utilize atrazine for growth. Furthermore, the pH of the medium was significantly decreased when strain P1 utilized ethylamine and isopropylamine as the nitrogen source for growth. The results suggest that nondegrader strain P1 could promote the atrazine biodegradation when co-cultured with strain DNS10. This phenomenon is due to metabolite exchange between the two strains. Culturing these two strains together is a new biostimulation strategy to enhance the biodegradation of atrazine by culturing these two strains together. Highlights • Growth of Enterobacter sp. P1 and Arthrobacter sp. DNS10 was promoted under co-culture condition. • Synergistic atrazine degradation was observed in co-culture of P1 and DNS10. • Strain P1 utilize atrazine metabolites as sole nitrogen source for growth. • The secretions of strain P1 promote the atrazine degrading ability of DNS10. • Expressions of atrazine-degrading genes in DNS10 were enhanced by co-cultures. [ABSTRACT FROM AUTHOR]

Abstract In aircraft design, structural optimization concerning transonic aeroelastic issues is computationally impractical, due to a great number of aeroelastic analyses are required in iterative process. Reduced-Order Model (ROM) method is convenient for transonic aeroelastic analyses; however, current ROMs are not reusable during iteration, hence the time consumption is still too high. To solve the problem, this study proposes an improved ROM suitable for Arbitrary Mode Shapes (ROM-AMS), which is reusable in iterative process. By adopting Principal Component Analysis, ROM-AMS method significantly reduces the number of basis mode shapes, while improves the accuracy of flutter analysis. In an optimization case, the weight of a cropped delta wing is reduced by 28.46%, and the efficiency is 900 times higher than that of traditional ROM approaches, which demonstrates the feasibility of this method in aeroelastic optimization. Highlights • A Reduced-Order Modeling method for transonic aeroelastic optimization is proposed. • Number of basis modes can be largely reduced by Principal Component Analysis. • Efficiency of optimization is two orders of magnitudes higher than previous ROMs. [ABSTRACT FROM AUTHOR]

Natural odour compounds could be a potential alternative to synthetic herbicides. The odour compound of Periploca sepium Bunge, named 2-hydroxy-4-methoxy-benzaldehyde (HMB), is a herbicidal compound. However, its herbicidal mechanism is unclear. In this experiment, the physiological and biochemical indices, ultrastructure, and photosynthetic function of the leaves of Humulus scandens (Lour.) Merr. treated by HMB were assessed to elucidate the herbicidal mechanism. The results of physiological and biochemical indices are as follows: First, after 4 h of treatment with 2.5 and 5.0 mg/mL, the damage rates in the membrane permeation assay were 74.7% and 89.1%, respectively. Second, compared to the negative control group, multiple physiological and biochemical indices of the two treated groups were changed, including catalase content (−18.5 and −26.5 ng/mL), superoxide dismutase content (−27.4 and −56.6 ng/mL), peroxidase content (382.0 and 880.0 ng/mL), reactive oxygen species content (16.7 and 27.2 ng/mL), malondialdehyde content (8.9 and 25.2 nmol/g), and water potential values (0.2 and 0.3 MPa), except for the photosynthetic pigment contents (chlorophyll a, b, and carotene). Furthermore, the results of transmission electron microscopy showed that the organelles in the mesophyll tissue cells disappeared and severe plasmolysis led to cell atrophy after 4 h of treatment. There were fewer starch granules after 24 h of treatment, but there was no obvious abnormality in the upper and lower epidermal cells. The results of photosynthetic function showed that in the light response, the net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), and stomatal limitation value of the tested leaves were lower than those of the negative control group by 26.6 μmol·m−2·s−1, 7.7 mmol·m−2·s−1, 0.9 mol·m−2·s−1, and 0.2, respectively. However, the intercellular CO 2 concentration (Ci) increased and was higher than the air CO 2 concentration. In the CO 2 response, the Pn, Tr and Gs of the tested leaves first increased and then decreased, but the Ci value continuously increased and finally reached 1727.5 μmol·mol−1. It is obvious that HMB may have inhibited the effect on the photosynthetic system of the tested leaves. Overall, HMB killed the weeds by destroying the structure and multiple physiological functions of the tested leaves. [Display omitted] • The odor compound from Periploca sepium Bunge, named 2-hydroxy-4-methoxy-benzaldehyde (HMB), is an herbicidal compound. • HMB have significantly affected the leaf physiology of Humulus scandens (Lour.) Merr. • The transmission electron microscopy (TEM) results showed that the organelles in the mesophyll cells of leaves disappeared. • The results of photosynthetic function showed that HMB have inhibited net photosynthetic rate (Pn) of test leaves. [ABSTRACT FROM AUTHOR]

The odor compound from Periploca sepium Bunge, 2-hydroxy-4-methoxy-benzaldehyde (HMB), is an allelochemical agent and is one of the least investigated isomers of vanillin. In this study, we used label-free quantitative proteomics analysis technology to investigate the effect of HMB on the protein expression of Humulus scandens (Lour.) Merr. leaves in July 2019 on Guiyang. A total of 269 proteins of 624 identified proteins were differentially expressed, among which 21.18% of the proteins were up-regulated and 32.71% down-regulated. These proteins were classified into 11 cell components and more than 20% of differentially expressed proteins were located in cell membrane and chloroplast. Functional classification analysis showed that 12 molecular functions were altered upon HMB treatment, and the ratio of catalytic activity was the highest (19.53%). At least 12 biological functions were affected, which involved small molecule metabolic processes, organic substance metabolic processes, gene expression, and photosynthesis. Our data provide resources and insights into the biochemical mechanism by which HMB kills weeds. [Display omitted] • Two-hydroxy-4-methoxy-benzaldehyde (HMB) was isolated from Periploca sepium Bunge. • A total of 269 proteins of tested leaves were 21.18% of up-regulated and 32.71% of down-regulatedy. • Over 20% of differentially expressed proteins were located in the cell membrane and chloroplast. • The differentially proteins were altered upon HMB treatment. • Twelve biological functions were affected by HMB. [ABSTRACT FROM AUTHOR]

Mancozeb is a metal-containing ethylene bis-dithiocarbamate fungicide widely used in agriculture. Ethylene thiourea (ETU) is the primary metabolite of Mancozeb. Mancozeb has been associated with spontaneous abortions and abnormal menstruation in women. However, the effects of Mancozeb and ETU on embryo attachment remain unknown. The human blastocyst surrogate trophoblastic spheroids (JEG-3), endometrial epithelial surrogate adenocarcinoma cells (Ishikawa), or human primary endometrial epithelial cells (EECs) monolayer were used in the spheroid attachment models. Ishikawa and EECs were pretreated with different concentrations of Mancozeb or ETU for 48 h before the attachment assay. Gene expression profiles of Ishikawa cells were examined to understand how Mancozeb modulates endometrial receptivity with Microarray. The genes altered by Mancozeb were confirmed by qPCR and compared with the ETU treated groups. Mancozeb and ETU treatment inhibited cell viability at 10 μg/mL and 5000 µg/mL, respectively. At non-cytotoxic concentrations, Mancozeb at 3 μg/mL and ETU at 300 μg/mL reduced JEG-3 spheroid attachment onto Ishikawa cells. A similar result was observed with human primary endometrial epithelial cells. Mancozeb at 3 μg/mL modified the transcription of 158 genes by at least 1.5-fold in Microarray analysis. The expression of 10 differentially expressed genes were confirmed by qPCR. Furthermore, Mancozeb decreased spheroid attachment possibly through downregulating the expression of endometrial estrogen receptor β and integrin β3, but not mucin 1. These results were confirmed in both overexpression and knockdown experiments and co-culture assay. Mancozeb but not its metabolite ETU reduced spheroid attachment through modulating gene expression profile and decreasing estrogen receptor β and integrin β3 expression of endometrial epithelial cells. • The pesticide Mancozeb exerts higher cytotoxicity than its metabolite ETU. • Mancozeb suppresses trophoblastic spheroid attachment onto endometrial epithelial cells at concentration 100-fold lower than ETU. • Mancozeb modulates the gene expression profile in the endometrial cells. • Mancozeb but not ETU decreases endometrial ERβ, integrin β3 and Mucin1 expression. • Knockdown of ERβ and integrin β3 decreases spheroid attachment. • Overexpression of ERb and integrin b3 nullifies the inhibitory effect of Mancozeb on spheroid attachment. [ABSTRACT FROM AUTHOR]

Urban green spaces play a crucial role in cities by providing near-natural environments that greatly impacts the health of residents. However, these green spaces have recently been scrutinized as potential reservoirs of antibiotic resistance genes (ARGs), posing significant ecological risks. Despite this concern, our understanding of the distribution, sources, and ecological risks associated with ARGs remains limited. In this study, we investigated the spatial distribution of soil ARGs using spatial interpolation and auto-correlation analysis. To apportion the source of soil ARGs in urban green spaces of Tianjin, Geo-detector method (GDM) was employed. Furthermore, we evaluated the ecological risk posed by ARGs employing risk quotients (RQ). The results of our study showed a significantly higher abundance of Quinolone resistance genes in the soil of urban green spaces in Tianjin. These genes were mainly found in the northwest, central, and eastern regions of the city. Our investigation identified three main factors contributing to the presence of soil ARGs: antibiotic production, precipitation, livestock breeding, and hospital. The results of ecological risk in RQ value showed a high risk associated with Quinolone resistance genes, followed by Aminoglycoside, Tetracycline, Multidrug, MLSB, Beta Lactam, Sulfonamide, and Chloramphenicol. Mantel-test and correlation analysis revealed that the ecological risk of ARGs was greatly influenced by soil properties and heavy metals. This study provides a new perspective on source apportionment and the ecological risk assessment of soil ARGs in urban green spaces. • Explore the spatial distribution of soil antibiotic resistance genes. • Identify the sources of soil antibiotic resistance genes via multiple models. • Assess the ecological risk of soil antibiotic resistance genes in urban green space. [ABSTRACT FROM AUTHOR]

[Display omitted] • M2 (PD) is the main metabolite of dammarane ginsenoside AD-1 in vivo. • Compound M3 was isolated from metabolites in vivo for the first time. • PD could significantly inhibit the proliferation and migration of MDA-MB-231 cells and induce G1-phase arrest. • PD could significantly inhibit the proliferation and migration of breast cancer in nude mice. • PD inhibited proliferation and metastasis of breast cancer cells by inducing the p38 MAPK/MMP9 pathway. Previous studies have shown that 20 (R)-25-methoxyl-dammarane-3 β , 12 β , 20 triol (AD-1) can inhibit various cancer cell lines. This study aimed to explore the effect and mechanism of AD-1 metabolite M2 (Panaxadiol; PD) on breast cancer cells of nude mice. Five AD-1 metabolites were isolated and identified using various chromatographic techniques. PD was the main component. In vitro results showed that PD could inhibit the proliferation and migration of MDA-MB-231 cells by inducing G1-phase arrest. In addition, PD down-regulated the expression of Cyclin D1, cdk2, cdk4, cdk6, P-p38, and MMP9, and up-regulated p21 and p27. In vivo results showed that PD could effectively reduce the volume, weight, and migration of breast cancer Transcriptomics analyzed 491 differentially expressed genes by GO and KEGG enrichment. RT-PCR verification confirmed that the significant down-regulation of MMP9 was consistent with transcriptomics results. In further research showed that PD regulated the protein expression of P-p38 and MMP9 in MAPK pathway. In summary, in vivo and in vitro studies showed that PD significantly inhibit the occurrence and development of breast cancer, possibly through the MAPK pathway. [ABSTRACT FROM AUTHOR]

Abstract: An integrative non-conjugative extrachromosomal genetic element, denoted as pSSVi, has been isolated from a Sulfolobus solfataricus P2 strain and was characterized. This genetic element is a double-stranded DNA of 5740 bp in size and contains eight open reading frames (ORFs). It resembles members of the pRN plasmid family in genome organization but shows only weak similarity to the latter in conserved regions. pSSVi has a copG gene similar to that of a pRN plasmid, encodes a large replication protein which, unlike a typical pRN RepA, contains no polymerase/primase domain, and lacks the plrA gene. Interestingly, pSSVi encodes an SSV-type integrase which probably catalyzes the integration of its genome into a specific site (a tRNAArg gene) in the S. solfataricus P2 genome. Like pSSVx, pSSVi can be packaged into a spindle-like viral particle and spread with the help of SSV1 or SSV2. In addition, both SSV1 and SSV2 appeared to replicate more efficiently in the presence of pSSVi. Given the versatile genetic abilities, pSSVi appears to be well suited for a role in horizontal gene transfer. [Copyright &y& Elsevier]

• For the first time, 16 metabolites of 20(R)-25-OCH 3 -PPD were isolated and identified, of which 10 were new compounds. • We first discovered the biotransformation of dammarane-type sapogenins into oleanane-type sapogenins in rats, found a series of metabolites that changed mainly at C-29. • We studied the anticancer mechanisms of active oleanane-type sapogenin (M6). All the results suggested that M6 manifested higher efficacy on inhibiting cancer cells proliferation by inducing cell apoptosis. 20(R)-25-methoxyl-dammarane-3 β ,12 β ,20-triol (AD-1, CN Patent: 201010107476.7) is a novel derivative of dammarane-type ginsenoside. AD-1 has been shown to inhibit cancer cell proliferation without significant host toxicity in vivo , and has excellent development potential as a new anti-cancer agent. This study was designed systematically to explore the metabolic pathway of ginseng sapogenins. The metabolism of drugs in the body is a complex biotransformation process where drugs are structurally modified to different molecules (metabolites) through various metabolizing enzymes. The compounds responsible for the effects of orally administered ginseng are believed to be metabolites produced in the gastrointestinal tract, so understanding the metabolism of the drug candidate can help to optimize its pharmacokinetics. In this study, faeces samples were collected and extracted after oral administration of AD-1. The 16 metabolites of AD-1 were isolated and identified for the first time with various chromatographic techniques, including semi-preparative high performance liquid chromatography, nuclear magnetic resonance spectroscopy, and mass spectrometry; of these 16 metabolites, 10 were novel compounds. We first discovered the biotransformation of dammarane-type sapogenins into oleanane-type sapogenins in rats and found a series of metabolites that changed, mainly at C-25 and C-29. This study provides new ideas for the metabolic pathway of ginseng sapogenins. The isolated compounds were screened for their effect on the viability and proliferation against cancer cell lines (Human A549, MCF-7, HELA, HO-8901 and U87). The discovery of novel active metabolites 3 β ,12 β ,21 α ,22 β -Hydroxy-24-norolean-12-ene (M6) may lead to a new or improved drug candidate. For one, M6 could inhibit the growth of all the tested cancer cells. Among the tested cell lines, M6 exhibited the most remarkable inhibitory effect on ovarian cancer HO-8901 cells, with IC 50 value of 2.086 μM. On this basis, we studied the anticancer mechanisms of M6. The results indicated that the pro-apoptotic feature of M6 acts via a mitochondrial pathway. Our results indicated that M6 exhibited a higher inhibitory effect on cancer-cell proliferation than AD-1 by inducing cell apoptosis. Our work provides data for future investigations on the metabolic mechanism of AD-1 in vivo and the potential for future research on developing a new drug. [ABSTRACT FROM AUTHOR]