Elaborating the role of rhamnolipids on the formation of humic substances during rice straw composting based on Fenton pretreatment and fungal inoculation.

Composting is a green and sustainable way to dispose and reuse agricultural wastes, but the low degradation rate during composting hinders its application. This study was conducted to explore the effect of added surfactant rhamnolipids after Fenton pretreatment and inoculation of fungi (Aspergillus fumigatus) into the compost on the formation of humic substances (HS) during rice straw composting, and explored the effect of this method. The results showed that rhamnolipids speeded up the degradation of organic matter and HS formation during composting. Rhamnolipids promoted the generation of lignocellulose-degrading products after Fenton pretreatment and fungal inoculation. The differential products benzoic acid, ferulic acid, 2, 4-Di-tert-butylphenol and syringic acid were obtained. Additionally, key fungal species and modules were identified using multivariate statistical analysis. Reducing sugars, pH, and total nitrogen were the key environmental factors that affected HS formation. This study provides a theoretical basis for the high-quality transformation of agricultural wastes.

Lanthanum-modified polydopamine loaded Acinetobacter lwoffii DNS32 for phosphate and atrazine removal: Insights into co-adsorption and biodegradation mechanisms.

A novel biobased composite was developed for the removal of phosphate (P) and atrazine from agricultural wastewater. A composite with strong P affinity and good biocompatibility, synthesized from La3+ and polydopamine (PDA), was immobilized onto an atrazine-degrading bacterium Acinetobacter lwoffii DNS32 (La/PDA/DNS32). Following Box-Behnken design optimization, the maximum removal rate of P (500 mg L-1) and atrazine (100 mg L-1) by La/PDA/DNS32 reached 28 % and 100 %, respectively. Density functional theory calculations revealed that La/PDA had more negative adsorption energy (-5.90 eV) than PDA alone and exhibited prominent electrophilic sites. Additionally, La/PDA-induced sorption of atrazine improved transmembrane transport and enhanced expression of degradation-associated genes in strain DNS32. La/PDA nanoparticles surrounding strain DNS32 provided a shielding effect and exhibited desirable biostability, thermal stability, and acid-alkaline resistance under contamination stress. This study demonstrates the promising potential of La/PDA/DNS32 in reducing the P and atrazine pollution caused by agricultural production.

Health risks of phthalates: A review of immunotoxicity.

Phthalates (PAEs) are known environmental endocrine disruptors that have been widely detected in several environments, and many studies have reported the immunotoxic effects of these compounds. Here, we reviewed relevant published studies, summarized the occurrence and major metabolic pathways of six typical PAEs (DMP, DEP, DBP, BBP, DEHP, and DOP) in water, soil, and the atmosphere, degradation and metabolic pathways under aerobic and anaerobic conditions, and explored the molecular mechanisms of the toxic effects of eleven PAEs (DEHP, DPP, DPrP, DHP, DEP, DBP, MBP, MBzP, BBP, DiNP, and DMP) on the immune system of different organisms at the gene, protein, and cellular levels. A comprehensive understanding of the mechanisms by which PAEs affect immune system function through regulation of immune gene expression and enzymes, increased ROS, immune signaling pathways, specific and non-specific immunosuppression, and interference with the complement system. By summarizing the effects of these compounds on typical model organisms, this review provides insights into the mechanisms by which PAEs affect the immune system, thus supplementing human immune experiments. Finally, we discuss the future direction of PAEs immunotoxicity research, thus providing a framework for the analysis of other environmental pollutants, as well as a basis for PAEs management and safe use.

Di(2-ethylhexyl) phthalate and dibutyl phthalate have a negative competitive effect on the nitrification of black soil.

Di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) are the most widely used plasticizers for agricultural mulching films and one of the most common organic pollutants in black soil. However, little is known about the effect of these two contaminants on nitrification in black soil. This study investigated the changes of 20 mg/kg DEHP and DBP on the diversity of nitrification microbial communities, the abundance of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) related genes, and the activities of key enzymes involved in nitrification. During ammonia oxidation, DEHP and DBP had uncompetitive inhibition of urease, reducing the copy number of amoA gene, and microorganisms (Azoarcus, Streptomyces and Caulobacter) would use inorganic nitrogen as a nitrogen source for physiological growth. During nitrite oxidation, the copy number of nxrA gene also reduced, and the relative abundance of chemoautotrophic nitrifying bacteria (Nitrosomonas and Nitrobacter) decreased. Moreover, the path analysis results showed that DEHP and DBP mainly directly or indirectly affect AOB and NOB through three ways. These results help better understand the ecotoxicological effects of DEHP and DBP on AOB and NOB in black soil.

Distribution of rare earth elements (REEs) and their roles in plant growth: A review.

The increasing use of rare earth elements (REEs) in various industries has led to a rise in discharge points, thus increasing discharge rates, circulation, and human exposure. Therefore, REEs have received widespread attention as important emerging pollutants. This article thus summarizes and discusses the distribution and occurrence of REEs in the world's soil and water, and briefly introduces current REEs content analysis technology for the examination of different types of samples. Specifically, this review focuses on the impact of REEs on plants, including the distribution and fractionation of REEs in plants and their bioavailability, the effect of REEs on seed germination and growth, the role of REEs in plant resistance, the physiological and biochemical responses of plants in the presence of REEs, including mineral absorption and photosynthesis, as well as a description of the substitution mechanism of REEs competing for Ca in plant cells. Additionally, this article summarizes the potential mechanisms of REEs to activate endocytosis in plants and provides some insights into the mechanisms by which REEs affect endocytosis from a cell and molecular biology perspective. Finally, this article discusses future research prospects and summarizes current scientific findings that could serve as a basis for the development of more sustainable rare earth resource utilization strategies and the assessment of REEs in the environment.

Streptacidiphilus fuscans sp. nov., a novel actinobacterium isolated from the root of pumpkin (Cucurbita moschata).

A novel acidophilic actinobacterium, designated strain NEAU-YB345T, was isolated from a pumpkin root collected from Mudanjiang, Heilongjiang Province, northeast PR China. Based on 16S rRNA gene sequence similarity and chemotaxonomic and morphological properties, the isolate was assigned to the genus Streptacidiphilus, with the high 16S rRNA gene sequence similarities to Streptacidiphilus melanogenes JCM 16224T (99.2 %), Streptacidiphilus anmyonensis JCM 16223T (99.1 %) and Streptacidiphilus jiangxiensis JCM 12277T (98.7 %). Its cell wall contained ll-diaminopimelic acid as the major diamino acid. Rhamnose, ribose, glucose and galactose were the detected sugars from the whole-cell hydrolysates. The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The menaquinones were MK-9(H8) and MK-9(H6). Major fatty acids were C16 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C15 : 0. Phylogenetic analysis using 16S rRNA gene and whole-genome sequences placed the strain in distinct clades but within the genus Streptacidiphilus. The DNA G+C content was 71.2 mol%. Based on DNA-DNA relatedness and physiological and biochemical data, the isolate could be distinguished from its closest relatives. Therefore, strain NEAU-YB345T represents a novel species of the genus Streptacidiphilus, for which the name Streptacidiphilus fuscans sp. nov. is proposed. The type strain is NEAU-YB345T (=CCTCC AA 2020030T=JCM 33976T).

Microbispora fusca sp. nov., a novel actinomycete isolated from the ear of wheat (Triticum aestivum L.).

A novel actinomycete, designated strain NEAU-HEGS1-5T, was isolated from the ear of wheat (Triticum aestivum L.) and characterized using a polyphasic approach. The morphological and chemotaxonomic characteristics of the strain coincided with those of members of the genus Microbispora. The results of 16S rRNA gene sequence analysis showed that the isolate was most closely related to Microbispora bryophytorum NEAU-TX2-2T (99.3 %), Microbispora camponoti 2C-HV3T (99.2 %), Microbispora amethystogenes JCM 3021T (99.1 %) and Microbispora rosea subsp. rosea JCM 3006T (98.5 %). However, two tree-making algorithms supported the position that strain NEAU-HEGS1-5T formed a distinct clade with M. bryophytorum NEAU-TX2-2T, M. camponoti 2C-HV3T and M. rosea subsp. rosea JCM 3006T. Furthermore, multilocus sequence analysis based on the 16S-gyr B-rpo B genes and a combination of DNA-DNA hybridization results and some physiological and biochemical properties demonstrated that the strain could be distinguished from its closest relatives. Therefore, it is proposed that strain NEAU-HEGS1-5T should be classified as representative of a novel species of the genus Microbispora, for which the name Microbispora fusca sp. nov. is proposed. The type strain is NEAU-HEGS1-5T (=CCTCC AA 2019030T=DSM 104648T).

Kribbella jiaozuonensis sp. nov., a novel actinomycete isolated from soil.

A novel actinobacterium, designated strain NEAU-THZ27T, was isolated from soil collected from the Cornel peak in Jiaozuo, Henan Province, PR China and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with those of members of the genusKribbella. The results of 16S rRNA gene sequence analysis showed that strain NEAU-THZ27T belongs to the genus Kribbella and was most closely related to Kribbella podocarpi YPL1T (98.96 %), Kribbella karoonensis Q41T (98.89 %), Kribbella aluminosa HKI 0478T (98.86%) and Kribbella hippodromi S1.4T (98.85 %), similarities to other type strains of species of the genus Kribbella were found to be less than 98.7 %. Phylogenetic analyses using the 16S rRNA gene sequence and multilocus sequence analysis using the concatenated gene sequences of the gyrB, rpoB, recA, relA and atpD genes all showed that the strain formed a separate branch in the genus Kribbella. The cell wall contained ll-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates were ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinone was MK-9(H4). Major fatty acids were iso-C16 : 0, iso-C14 : 0 and anteiso-C15 : 0, these chemotaxonomic data supported the affiliation of strain NEAU-THZ27T to the genus Kribbella. The DNA G+C content was 68.0 mol%. Furthermore, the strain could be clearly distinguished by concatenated gene genetic distances, the combination of DNA-DNA hybridization results and some phenotypic characteristics. Therefore, it is proposed that strain NEAU-THZ27T represents a novel species of the genus Kribbella, for which the name Kribbella jiaozuonensis sp. nov. is proposed. The type strain is NEAU-THZ27T (=CGMCC 4.7504T=DSM 105535T).

Arthrobacter celericrescens sp. nov., isolated from forest soil.

A novel bacterial strain, designated NEAU-SA2T, was isolated from forest soil collected from the Zhangjiajie city, Hunan Province, PR China and characterised using a polyphasic approach. The cells were aerobic, Gram-stain-positive, non-flagellated and rod-coccus-shaped. The strain grew optimally at 28 °C, pH 7.0 and with 0 % NaCl (w/v). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the organism should be assigned to the genus Arthrobacter and was closely related to Arthrobacter cupressi DSM 24664T (98.89 %) and Arthrobacter silvisoli CCTCC AB 2017271T (98.41 %), which was further confirmed by multilocus sequence analysis. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and C16 : 0; MK-9(H2) was the predominant respiratory quinone. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified glycolipid. The peptidoglycan type was A3α, and the cell-wall sugars were glucose and galactose. The genomic G+C content of strain NEAU-SA2T was 67.04 mol%. The average nucleotide identity values between NEAU-SA2T and A. cupressi DSM 24664T and A. silvisoli CCTCC AB 2017271T were 88.57-90.94 %. The digital DNA-DNA hybridisation values between strain NEAU-SA2T and its most closely related species were 37.00 and 41.10 %, respectively, again indicating that they belong to different taxa. Therefore, strain NEAU-SA2T represents a novel species of the genus Arthrobacter, for which the name Arthrobacter celericrescens sp. nov. is proposed. The type strain is NEAU-SA2T (=DSM 106718T=CCTCC AB 2017272T).

Streptomyces monticola sp. nov., a novel actinomycete isolated from soil.

A novel actinobacterium, designated strain NEAU-GS4T, was isolated from soil collected from Mount Song and characterised using a polyphasic approach. 16S rRNA gene sequence similarity studies showed that strain NEAU-GS4T belongs to the genus Streptomyces, being closely related to Streptomyces spectabilis JCM 4308T (98.8%), Streptomyces sclerotialus DSM 43032T (98.3%) and Streptomyces lasiicapitis 3H-HV17(2)T (98.0%). A multilocus sequence analysis based on five house-keeping genes (atpD, gyrB, rpoB, recA and trpB) also indicated that strain NEAU-GS4T should be assigned to the genus Streptomyces. The major menaquinones were identified as MK-9(H6), MK-9(H8) and MK-9(H4). The polar lipid profile was found to contain diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositolmannosides and an unidentified phospholipid. The major fatty acids were identified as anteiso-C15:0, iso-C16:0 and anteiso-C17:0. Moreover, DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-GS4T can be clearly differentiated from its closely related species of the genus Streptomyces. Therefore, it is concluded that strain NEAU-GS4T represents a novel species of the genus of Streptomyces, for which the name Streptomyces monticola sp. nov. is proposed. The type stain is NEAU-GS4T (=CGMCC 4.7467T = DSM 105116T).

Nocardia bovistercoris sp. nov., an actinobacterium isolated from cow dung.

A novel actinobacterium, designated strain NEAU-351T, was isolated from cow dung collected from Shangzhi, Heilongjiang Province, northeast PR China and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-351T belonged to the genus Nocardia, with the highest similarity (98.96 %) to Nocardia takedensis DSM 44801T and less than 98.0 % identity with other type strains of the genus Nocardia. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major menaquinone was observed to contain MK-8(H4, ω-cycl) (78.2 %). The fatty acid profile mainly consisted of C16 : 0, C18 : 1 ω9c and 10-methyl C18 : 0. Mycolic acids were present. The genomic DNA G+C content of strain NEAU-351T was 68.1 mol%. In addition, the average nucleotide identity values between strain NEAU-351T and its reference strains, Nocardia takedensis DSM 44801T and Nocardia arizonensis NBRC 108935T, were found to be 81.4 and 82.9 %, respectively, and the level of digital DNA-DNA hybridization between them were 24.8 % (22.5-27.3 %) and 26.3 % (24-28.8 %), respectively. Here we report on the taxonomic characterization and classification of the isolate and propose that strain NEAU-351T represents a new species of the genus Nocardia, for which the name Nocardia bovistercoris is proposed. The type strain is NEAU-351T (=CCTCC AA 2019090T=DSM 110681T).

Arthrobacter silvisoli sp. nov., isolated from forest soil.

A novel Gram-stain-positive, strictly aerobic strain, NEAU-SA1T, which showed a rod-coccus growth life cycle, was isolated from forest soil from Zhangjiajie, Hunan Province, China. The isolate grew at 10-40 °C (optimum 28 °C), at pH 5.0-10.0 (optimum pH 7.0) and in the presence of up to 5 % (w/v) NaCl, although NaCl was not required for growth. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-SA1T belonged to the genus Arthrobacter and was closely related to Arthrobacter cupressi DSM 24664T (98.1 % similarity). Average nucleotide identity values between NEAU-SA1T and A. cupressi DSM 24664T were 88.91 and 87.41 % by ANIm and ANIb analysis, respectively. The in silico DNA-DNA hybridization value between strain NEAU-SA1T and A. cupressi DSM 24664T was 34.20 %, again indicating they belong to different taxa. The genomic DNA G+C content was 66.74 mol%. The major cellular fatty acids (>10 %) were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two unidentified glycolipids. The predominant menaquinone was MK-9(H2). The peptidoglycan type was A3α with an interpeptide bridge comprising l-Lys and l-Ala. Glucose, ribose and galactose were the whole-cell sugars. On the basis of morphological, physiological, biochemical and chemotaxonomic analysis, strain NEAU-SA1T was classified as representing a novel species in the genus Arthrobacter, for which the name Arthrobacter silvisoli sp. nov. is proposed. The type strain is NEAU-SA1T (=DSM 106716T=CCTCC AB 2017271T).

Dryocrassin ABBA Induces Apoptosis in Human Hepatocellular Carcinoma HepG2 Cells Through a Caspase-Dependent Mitochondrial Pathway.

BACKGROUND: Biological and pharmacological activities of dryocrassin ABBA, a phloroglucinol derivative extracted from Dryopteris crassirhizoma, have attracted attention. In this study, the apoptotic effect of dryocrassin ABBA on human hepatocellular carcinoma HepG2 cells was investigated. MATERIALS AND METHODS: We tested the effects of dryocrassin ABBA on HepG2 in vitro by MTT, flow cytometry, real-time PCR, and Western blotting. KM male mice were used to detect the effect of dryocrassin ABBA on H22 cells in vivo. RESULTS: Dryocrassin ABBA inhibited the growth of HepG2 cells in a concentration-dependent manner. After treatment with 25, 50, and 75 µg/mL dryocrassin ABBA, the cell viability was 68%, 60% and 49%, respectively. Dryocrassin ABBA was able to induce apoptosis, measured by propidium iodide (PI)/annexin V-FITC double staining. The results of real-time PCR and Western ting showed that dryocrassin ABBA up-regulated p53 and Bax expression and inhibited Bcl-2 expression which led to an activation of caspase-3 and caspase-7 in the cytosol, and then induction of cell apoptosis. In vivo experiments also showed that dryocrassin ABBA treatment significantly suppressed tumor growth, without major side effects. CONCLUSIONS: Overall, these findings provide evidence that dryocrassin ABBA may induce apoptosis in human hepatocellular carcinoma cells through a caspase-mediated mitochondrial pathway.

Ovate family protein1 interaction with BLH3 regulates transition timing from vegetative to reproductive phase in Arabidopsis.

Three-Amino-acid-Loop-Extension(TALE) homeodomain transcription factor BLH3 regulates timing of transition from vegetative to reproductive phase. Previous preliminary results obtained using large-scale yeast two-hybrids indicate that BLH3 protein possibly interact with Ovate Family Proteins(OFPs) transcription co-regulators. Nevertheless, it is uncertain whether OFP1-BLH3 complex is involved in regulation of timing of transition from vegetative to reproductive phase in Arabidopsis. The interaction between BLH3 and OFP1 was re-tested and verified by a yeast two-hybrid system. We found that the BLH3-OFP1 interaction was mainly mediated through the BLH3 homeodomain. Meanwhile, this interaction was further confirmed by bimolecular fluorescence complementation (BiFC) in vivo. Further, by establishing protoplast transient expression, we discovered that BLH3 acts as a transcriptional activator, whereas OFP1 functioned as a repressor. The interactions between OFP1 and BLH3 can reduce BLH3 transcriptional activity. The ofp1 mutant lines and blh3 mutant lines, OFP1 overexpress lines and BLH3 overexpress lines can both influence timing of transition from vegetative to reproductive phase. Furthermore, 35s:OFP1/blh3 plants exhibited flowering and leaf quantity similar to that of the wild-type controls. 35s:BLH3/ofp1 plants flowered earlier and had less leaves than wild-type controls, indicating that OFP1 protein might depend partially on BLH3 in its function to regulate the timing of transition from vegetative to reproductive phase. These results support our assumption that, by interacting with OFP1, BLH3 forms a functional protein complex that controls timing of progression from vegetative to reproductive phase, and OFP1 might negatively regulate BLH3 or the BLH-KNOX complex, an important interaction for sustaining the normal transition from vegetative to reproductive phase.