Selenium-phosphorus modified biochar reduces mercury methylation and bioavailability in agricultural soil.

Biochar is a frequently employed for solidifying and stabilizing mercury (Hg) contamination in soil. However, it often results in an elevated presence of soil methylmercury (MeHg), which introduces new environmental risks. Consequently, there is a necessity for developing a safer modified biochar for use in Hg-contaminated soil. This study employed sodium selenite (at a safe dosage for soil) and hydroxyapatite to modify straw biochar (BC) based on the interaction between selenium (Se) and phosphorus (P). This process led to the formation of Se-modified biochar (Se-BC), P-modified biochar (P-BC), and Se and P co-modified biochar (Se-P-BC). Additionally, solvent adsorption experiments and pot experiments (BC/soil mass ratio: 0.5 %) were conducted to investigate the impacts of these soil amendments on soil Hg methylation and bioavailability. Se and P co-modification substantially increased the surface area, pore volume, and Hg adsorption capacity of BC. BC treatment increased the simulated gastric acid-soluble Hg, organo-chelated Hg, and MeHg in the soil. Conversely, Se-P-BC significantly reduced these forms of Hg in the soil, indicating that Se-P-BC can transform soil Hg into less bioavailable states. Among the different biochar treatments, Se-P-BC exhibited the most pronounced reductions in soil MeHg, total Hg, and MeHg in water spinach, achieving reductions of 63 %, 71 %, and 70 %, respectively. The co-modification of Se and P displayed a synergistic reduction effect in managing soil Hg pollution, which is associated with the increase of available Se in the soil due to phosphorus addition. The significantly reduced dissolved organic carbon and the abnormally high SO42- concentration in the soil of Se-P-BC treatment also inhibited Hg methylation and bioavailability in the soil. In summary, Se-P-BC substantially increased reduction percentage in plant Hg content while mitigating the risk of secondary pollution arising from elevated soil MeHg.

Selenium/sulfur-modified montmorillonite materials mitigate mercury pollution in farmland.

Selenium (Se) amendment could reduce mercury (Hg) bioaccumulation in crops, but sometimes it could cause excessive Se accumulation in crops and potential Se exposure risks for humans. In this study, we designed and synthesized selenium and sulfur-modified montmorillonite materials (Se/S-Mont) to effectively reduce mercury levels and avoid excessive Se enrichment in plants. The results of pot experiments (1 g Se/S-Mont/100 g soil) and field microplot trials (0.3 g Se/S-Mont/100 g soil, 8 t/ha) showed that Se/S-Mont amendments significantly reduced the Hg concentrations in water spinach and hybrid Pennisetum by 28-68% and 57%-92% (P < 0.05), respectively, while they did not lead to excessive Se bioaccumulation in the plants. Se/S-Mont was more efficient in mitigating soil Hg pollution than adding raw materials (e.g., NaSeO3) and their combinations, and they significantly reduced the available Se fraction in the soil and the Se levels in the plants (P < 0.05). The potential mechanisms revealed by X-ray absorption near-edge spectra (XANES) and pot experiments were the adsorption and slow release of Hg, S, and Se by Se/S-Mont, the high affinity between Hg and Se, competition between Se and S, and the formation of stable complexes containing Se-S-Hg. The Se/S-Mont immobilizer was easy to prepare and required the application of small amounts, and the remediation effect was relatively stable and exhibited few negative effects; therefore, the approach showed high environmental and economic potentials.

Effect of iron cyclic transformation on the natural purification of antimony in contaminated reservoirs of mines.

To further understand the purification mechanism of antimony (Sb) in reservoirs, samples of stratified water and bottom interface sediment were collected in this study. The cross-flow ultrafiltration technique was used to separate the truly dissolved (<1 kDa) and colloidal (1 kDa-0.45 µm) phases of water, and two modified sequential extraction techniques were used to determine the Sb and Fe mineral forms in sediment, respectively. The results showed that the total Sb concentration could decrease from 142.2 µg/L in surface water to 98.6 µg/L at 16 m; this was contributed to by the removal of truly dissolved Sb. In comparison to particulate Sb (>0.45 µm), the formation of colloidal Sb played a greater role in the purification process. There was a positive correlation between Sb and Fe in the colloidal phase (r = 0.45, P < 0.05). The generation of colloidal Fe could be promoted by higher temperatures, pH values, DO, and DOC in the upper layer (0-5 m). However, the complexation of DOC with colloidal Fe inhibited the adsorption of truly dissolved Sb. After entering the sediment, the secondary release of Sb could not increase the Sb concentration in the lower layer obviously, while the supplementation of Fe(III) could further enhance Sb natural purification.

Structure Characterization and Anti-Inflammatory Activity of Polysaccharides from Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes) by Microwave-Assisted Freeze-Thaw Extraction.

A water-soluble polysaccharide (GLP-2) was isolated and purified from Ganoderma lucidum by the microwave-assisted freeze-thaw method. Microwave-assisted rapid thawing treatment can greatly improve the extraction yield of polysaccharides. The chemical structure of GLP-2 was analyzed with FT-IR, HPLC, GC-MS, and NMR spectrometry. It was proved that GLP-2 is mainly composed of ß-1,3-glucose and ß-1,6-glucose. The chain conformation of GLP-2 was analyzed by SEC-MALLS-RI, indicating that GLP-2 adopts semi-rigid chain conformation. Its molecular weight is 16.7 × 104, and its molecular size is about 61.2 nm. MTT assay indicated that GLP-2 was non-toxic to RAW 264.7 cells in vitro. The results of anti-inflammatory studies showed that GLP-2 can inhibit the production of NO, TNF-α, IL-1ß, and IL-6 in RAW 264.7 macrophage stimulated by lipopolysaccharide (LPS). The above data showed that the extraction method used in this study can obtain a high-yield polysaccharide with anti-inflammatory activity.

Arsenic(iii) removal from aqueous solution using TiO2-loaded biochar prepared by waste Chinese traditional medicine dregs.

Oxidation of As(iii) to As(v) is an effective way to improve the performance of most arsenic removal technologies. In this study, a new alternative biosorbent, TiO2-loaded biochar prepared by waste Chinese traditional medicine dregs (TBC) was applied in remediation for As(iii) from aqueous solution. Compared with unmodified biochar, the specific surface areas and total pore volumes of TBC increased while the average aperture decreased due to the loading of nano-TiO2. The X-ray diffraction (XRD) of TBC confirmed that the precipitated titanium oxide was primarily anatase. pH did not have a significant effect on the adsorption capacity at 10 mg L-1 As(iii) in suspension with a pH ranging from 2 to 10. Adsorption kinetics data were best fitted by the pseudo-second-order model (R 2 > 0.999). The Sips maximum adsorption capacity was 58.456 mg g-1 at 25 °C, which is comparable with other adsorbents reported in previous literature. The Gibbs free energy (ΔG) of As(iii) adsorption was negative, indicating the spontaneous nature of adsorption. The results of free radical scavenging and N2 purging experiments indicated that O2 acted as an electron accepter and O2˙- dominated the oxidation of As(iii). The oxidation of As(iii) obviously affected the adsorption capacity for As(iii) by TBC. X-ray photoelectron spectroscopy (XPS) studies showed that As(iii) and As(v) existed on the surface of TBC, suggesting that the oxidation of As(iii) occurred. TBC played multiple roles for As(iii), including direct adsorption and photocatalytic oxidation adsorption. Regeneration and stability experiments showed that TBC was an environment-friendly and efficient adsorbent for As(iii) removal.

Production of Hydroxyl Radicals from Oxygenation of Simulated Acid Mine Drainage in Presence of Extracellular Polymers Substances.

The reaction mechanisms Fe(II) abiotic oxidation produce ·OH by CaCO3-induced in acid mine drainage (AMD) are well-documented, but little is known about the influence of extracellular polymeric substances (EPS) secreted by microorganisms on Fe(II) oxidation in AMD. In this study, ·OH production was experimently measured from oxygenation of simulated AMD in the presence of EPS. The cumulative ·OH increased from 56.75 to 158.70 µM within 24 h at pH 3 with the increase in EPS concentration from 0 to 12 mg/L. An appropriate pH (about 6) and EPS (6 mg/L) concentration were required for the moderate rate of Fe(II) oxidation. Besides, the yield of ·OH increased remarkably with the addition of Fe3+. In the presence of EPS, ·OH production is attributed mainly the complexation of Fe(II) with EPS, of which is rich of carboxyl and hydroxyl groups. The findings provide fundamental supplement of ·OH production from Fe(II) oxidation by microorganisms in natural AMD.

Effective Sb(V) removal from aqueous solution using phosphogypsum-modified biochar.

Antimonate is the dominant form of antimony (Sb) in Sb mine water. The treatment of high-Sb mine water essentially reduces the discharge of antimonate oxyanions ([Sb(OH)6]-) in it. Biochar obtained from phosphogypsum-modified anaerobic digested distillers' grain (PADC) can effectively adsorb antimonate from water. In this work, using batch adsorption experiments, mathematical models, and characterization methods, the mechanism of Sb(V) adsorption by PADC was studied. Compared with pristine biochar, PADC biochar showed abundant lamellar and vesicular structures with significant calcium ion loading on the surface. The kinetics data of the adsorption of Sb(V) on the PADC biochar followed the Elovich equation (R2 = 0.992), indicating that heterogeneous adsorption had occurred. The results also showed that intraparticle diffusion played an important role in controlling Sb(V) adsorption by PADC biochar. The Redlich-Peterson model best fit the Sb(V) adsorption isotherm (R2 = 0.997), indicating that the adsorption was a combination of the Langmuir and Freundlich models. The maximum adsorption capacity of PADC biochar for Sb(V) is 8123 mg/kg, which is more than twice that of the pristine biochar (3487 mg/kg) and is sufficient for Sb(V) treatment in most mine water. Fourier transform infrared (FTIR) spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), and Transmission electron microscopy with energy dispersive X-ray spectroscopy (TEM-EDS) analyses revealed that the dominant mechanism of Sb(V) removal by PADC biochar was the formation of Ca-O-Sb complexes or amorphous surface precipitation as well as electrostatic adsorption. This work demonstrated the potential of PADC biochar in the treatment of Sb-contaminated mine water.

Three New Aglain Derivatives from Aglaia odorata Lour. and Their Cytotoxic Activities.

Three new aglain derivatives (1-3), one known aglain derivative (4), two known rocaglamide derivatives (5 and 6), four known triterpenoids (7-10), and three steroids (11-13) were isolated from Aglaia odorata Lour. Their structures were established through the analysis of detailed spectroscopic data and electronic circular dichroism calculations. Five compounds (1 and 4-7) exhibited cytotoxic activities on human leukemia cells (HEL) and human breast cancer cells with IC50 values in the range of 0.03-8.40 µM. In particular, the cytotoxicity of compound 5 was six times stronger than that of the positive control (adriamycin) in HEL cell lines.

Comparing the effects of calcium and magnesium ions on accumulation and translocation of cadmium in rice.

Rice (Oryza sativa L.) is one of China's most important food crops, and it is considered the primary source of human exposure to cadmium (Cd) pollution. Adding calcium (Ca) and magnesium (Mg) to the plant nutrient solutions reduces the accumulation of Cd in the rice, but under the same condition, which one has the better effect remains unclear. Thus, hydroponic experiments were performed to compare the effects of Ca and Mg ions with concentration gradients (0.10, 0.25, and 0.50 g/L, respectively) on the absorption, distribution, and translocation of Cd in rice. The Cd contents of roots, stems, leaves, panicles, husks, and grains in different growth stages were determined. The results revealed that the supplementation of both Ca and Mg influenced the Cd accumulation and translocation in rice tissues. The Cd concentrations of different patterns were in the following order: roots > stems > leaves ≈ panicles ≈ husks > grains. Both of Ca and Mg had an apparent antagonism with Cd in different parts of the rice plant, and the antagonism was more obvious in the high Cd stress treatments. With the addition of 0.1 g/L Ca2+ and Mg2+ ions, the grain Cd contents increased, while the application of 0.25 and 0.5 g/L Ca2+ and Mg2+ ions reduced grains Cd by 19.08-38.99%, with the average value of 26.75%. Under the same concentrations, the grain Cd content of Ca treatments was lower than that of Mg treatments by 8.74%. In the Ca (Mg)-deficient and Ca (Mg)-sufficient conditions, the husks and panicles accumulated Cd to hinder Cd translocation, respectively. Altogether, the results of this study indicated that Ca had a greater effect for decreasing rice Cd accumulation and translocation than Mg, and the panicle and husk were the important parts for reducing Cd translocation to grain, and these might be a focal point for the future research. It was possible to plant and grow rice in Cd-polluted soil and that the accumulation and translocation of Cd in rice plants could be reduced by optimizing soil nutrient elements.

A Cotton Lignin Biosynthesis Gene, GhLAC4, Fine-Tuned by ghr-miR397 Modulates Plant Resistance Against Verticillium dahliae.

Plant lignin is a component of the cell wall, and plays important roles in the transport potential of water and mineral nutrition and plant defence against biotic stresses. Therefore, it is necessary to identify lignin biosynthesis-related genes and dissect their functions and underlying mechanisms. Here, we characterised a cotton LAC, GhLAC4, which participates in lignin biosynthesis and plant resistance against Verticillium dahliae. According to degradome sequencing and GUS reporter analysis, ghr-miR397 was identified to directedly cleave the GhLAC4 transcript through base complementary. GhLAC4 knockdown and ghr-miR397 overexpression significantly reduced basal lignin content compared to the control, whereas ghr-miR397 silencing significantly increased basal lignin levels. Based on staining patterns and GC/MS analysis, GhLAC4 acted in G-lignin biosynthesis. Under V. dahliae infection, we found that G-lignin content in ghr-miR397-knockdowned plants significantly increased, compared to these plants under the mock treatment, while G-lignin contents in GhLAC4-silenced plants and ghr-miR397-overexpressed plants treated with pathogen were comparable with these plants treated with mock, indicating that GhLAC4 participates in defence-induced G-lignin biosynthesis in the cell wall. Knockdown of ghr-miR397 in plants inoculated with V. dahliae promoted lignin accumulation and increased plant resistance. The overexpression of ghr-miR397 and knockdown of GhLAC4 reduced lignin content and showed higher susceptibility of plants to the fungal infection compared to the control. The extract-free stems of ghr-miR397-knockdowned plants lost significantly less weight when treated with commercial cellulase and V. dahliae secretion compared to the control, while the stems of ghr-miR397-overexpressed and GhLAC4-silenced plants showed significantly higher loss of weight. These results suggest that lignin protects plant cell walls from degradation mediated by cellulase or fungal secretions. In summary, the ghr-miR397-GhLAC4 module regulates both basal lignin and defence-induced lignin biosynthesis and increases plant resistance against infection by V. dahliae.

Triacylglycerol biosynthesis in shaded seeds of tung tree (Vernicia fordii) is regulated in part by Homeodomain Leucine Zipper 21.

Light quantity and quality affect many aspects of plant growth and development. However, few reports have addressed the molecular connections between seed oil accumulation and light conditions, especially dense shade. Shade-avoiding plants can redirect plant resources into extension growth at the expense of leaf and root expansion in an attempt to reach areas containing richer light. Here, we report that tung tree seed oil accumulation is suppressed by dense shade during the rapid oil accumulation phase. Transcriptome analysis confirmed that oil accumulation suppression due to dense shade was attributed to reduced expression of fatty acid and triacylglycerol biosynthesis-related genes. Through weighted gene co-expression network analysis, we identified 32 core transcription factors (TFs) specifically upregulated in densely shaded seeds during the rapid oil accumulation period. Among these, VfHB21, a class I homeodomain leucine zipper TF, was shown to suppress expression of FAD2 and FADX, two key genes related to α-eleostearic acid, by directly binding to HD-ZIP I/II motifs in their respective promoter regions. VfHB21 also binds to similar motifs in the promoters of VfWRI1 and VfDGAT2, two additional key seed lipid regulatory/biosynthetic genes. Functional conservation of HB21 during plant evolution was demonstrated by the fact that AtWRI1, AtSAD1, and AtFAD2 were downregulated in VfHB21-overexpressor lines of transgenic Arabidopsis, with concomitant seed oil reduction, and the fact that AtHB21 expression also was induced by shade. This study reveals some of the regulatory mechanisms that specifically control tung tree seed oil biosynthesis and more broadly regulate plant storage carbon partitioning in response to dense shade conditions.

Dietary watermelon residue influencing the nonspecific immunity of juvenile Pseudorasbora parva.

The study explored the improvement of disease resistance, non-specific immunity and anti-oxidation reactions for Pseudorasbora parva (PP) using dietary watermelon residue. The cumulative PP mortality and the pathogenic bacteria number in 15-45% groups reduced relative to those in control group (CK). Under 15-45% groups, AKP, ACP activities and akp, acp genes expression levels were increased markedly in nonspecific immunity system. Similarly, antioxidant response (SOD, CAT activities) and their genes was promoted also at 15-45% groups. Organic matter (vitamin and polyphenols) in watermelon residue improved AKP, ACP, SOD, CAT activities by increasing corresponding gene expressions. Theoretically, they could also function as stimulus signal, active center or composition to modulate enzyme activities and gene expressions. Besides, watermelon residue ameliorated NF-kB, mTOR responses pathway, and consequently suppressed Aeromonas hydrophila which augmented disease resistance.

New Insights into Selenium Enrichment in the Soil of Northwestern Guizhou, Southwest China.

Selenium (Se) is an essential trace element for animals and plants. Se in soil has an important influence on the Se intake by animals and plants. To explore the source of Se in soils of the zinc-smelting area in northwest Guizhou, China, 271 topsoils and 50 deep soil samples were collected, and the concentration, speciation and distribution of Se in soils were analysed. The results showed that the concentration of Se in topsoils ranged from 0.2 mg/kg to 1.79 mg/kg, with an average of 0.84 mg/kg, which was more than 2 times of that in deep soil. These observations indicated that Se was enriched in the surface layer of soil. In terms of spatial distribution, high-Se topsoils (> 1.0 mg/kg) were mainly distributed near the zinc smelting area, and topsoil samples with relatively low content of Se were mainly distributed in areas with less human activities influence. The Se occurrence species in topsoils were in the order of residue, organic-binding, humic-acid binding, water-soluble, Fe/Mn/Al oxide-binding, carbonate-binding and ion-exchange. The contribution of residual Se to total Se in topsoil was decisive, and the content of other species of selenium changed slightly. The Se speciation that was residual in soil is difficult for plants to utilize, which is consistent with previous studies on seleniferous soils caused by zinc smelting. These results indicated that the main reason for Se enrichment in the topsoils of northwest Guizhou Province was indigenous zinc smelting.

Effect of Ginkgo biloba extract on pacemaker channels encoded by HCN gene.

BACKGROUND: In the present study, the electropharmacological activity of traditional Chinese medicine, Ginkgo biloba extract (GBE), on human hyperpolarization-activated nucleotide-gated (HCN) channels and the underlying "funny" currents was investigated. METHODS: Standard two-electrode voltage-clamp recordings were employed to examine the properties of cloned HCN subunit currents expressed in Xenopus oocytes under controlled conditions and GBE administration. RESULTS: We found that GBE irreversibly inhibited the HCN2 and HCN4 channel currents in a concentration-dependent fashion and that the HCN4 current was more sensitive to GBE compared with HCN2. In addition, GBE inhibition of the current amplitudes of HCN2 and HCN4 currents was accompanied by a decrease in the activation and deactivation kinetics. CONCLUSION: The results of this study contribute toward illustrating the antiarrhythmic mechanism of GBE, which might be useful for the treatment of arrhythmia.

Synergistic anti-inflammatory effects of silibinin and thymol combination on LPS-induced RAW264.7 cells by inhibition of NF-κB and MAPK activation.

BACKGROUND: Combination drug therapy has become an effective strategy for inflammation control. The anti­inflammatory capacities of silibinin and thymol have each been investigated on its own, but little is known about the synergistic anti-inflammatory effects of these two compounds. PURPOSE: This study aims to investigate the synergistic anti-inflammatory effects of silibinin and thymol when administered in combination to lipopolysaccharide (LPS)-induced RAW264.7 cells. METHODS: RAW264.7 cells were pre-treated with silibinin and thymol individually or in combination for 2 h before LPS stimulation. Cell viability was detected by the MTT assay. Nitric oxide (NO) production was measured by Griess reagent. Reactive oxygen species (ROS) was evaluated by 2',7'-dichlorofluorescein-diacetate. ELISA was used to detect tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Western blot was performed to analyse the protein expression of LPS-induced RAW264.7 cells. RESULTS: We observed a synergistic anti-inflammatory effect of silibinin and thymol when administered in combination to LPS-induced RAW264.7 cells. Silibinin combined with thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) had more potent effects on the inhibition of NO, TNF-α, and IL-6 than those exerted by individual administration of these compounds in LPS-induced RAW264.7 cells. The combination of silibinin and thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) strongly inhibited ROS and cyclooxygenase-2 (COX-2). More importantly, the combination of silibinin and thymol (40 µM and 120 µM respectively, with the molar ratio 1:3) was also successful in inhibiting nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activities. Our results suggest that the synergistic anti-inflammatory effects of silibinin with thymol were associated with the inhibition of NF-κB and MAPK signalling pathways. CONCLUSION: The combination of silibinin and thymol (40 µM and 120 µM, respectively, with the molar ratio 1:3) could inhibit inflammation by suppressing NF-κB and MAPK signalling pathways in LPS-induced RAW264.7 cells.

Origins and features of pectate lyases and their applications in industry.

Pectate lyase treatment can be an alternative strategy of the chemical processing, which causes severe environmental pollution, and has been broadly studied and applied for diverse industrial applications including textile industry, beverage industry, pulp processing, pectic wastewater pretreatment, and oil extraction. This review gave a brief description of the origins, enzymatic characterizations, structure, and applications of pectate lyases (Pels). Most of the reported pectate lyases are originated from microorganisms with a small number of them from plants and animals. Due to the diverse environments that these microorganisms exist, Pels present diversified features, especially for the range of optimal pH and temperature. The diversified biochemical properties of Pels define their applications in different industries, and the applications of alkaline Pels on cotton bioscouring and ramie degumming in textile industry were focused in this review. This review also discussed the perspectives of the development and applications of Pels. KEY POINTS: • The first review on pectate lyase focusing on biotechnological applications. • Origins, features, structures, applications of pectate lyases reviewed. • Applications of alkaline Pels in textile industry demonstrated. • Perspectives on future development and applications of Pels discussed.

Rhodopseudomonas sphaeroides treating mesosulfuron-methyl waste-water.

The soybean processing wastewater (SPW) supplementation to facilitate the simultaneously treatment (SPW and mesosulfuron-methyl) of wastewater and production of biological substances by Rhodopseudomonas sphaeroides (R. sphaeroides) was discussed. Compared with the control group, with the addition of SPW, mesosulfuron-methyl was removed, and the yields of single-cell proteins, carotenoids, and bacteriochlorophyll were increased. In the 3 mg/L dose group, the mesosulfuron-methyl removal rate reached 97% after 5 days. Molecular analysis revealed that mesosulfuron-methyl exhibited induction effects on expression of the cpm gene and regulation effects on the synthesis of cytochrome P450 monooxygenases (P450) by activating HKs gene in TCS signal transduction pathway. For R. sphaeroides, this induction process required 1 day. The synthesis of P450 occurred 1 day after inoculation. Prior to expressing cpm gene and synthesizing P450, R. sphaeroides need a period of time to adapt to external mesosulfuron-methyl stimulation. However, the R. sphaeroides growth could not be maintained for more than 1 day due to the lack of organic matter in the raw wastewater. The SPW supplementation provided a sufficient carbon source in four groups with added SPW. After 5 days, R. sphaeroides became the dominant microflora in the wastewater. This new method could complete the treatment of mixed wastewater, the increased of biological substances output and the reuse of wastewater and R. sphaeroides cells as resources at the same time.

Response of the photosynthetic activity and biomass of the phytoplankton community to increasing nutrients during cyanobacterial blooms in Meiliang Bay, Lake Taihu.

Nutrient enrichment facilitates algal outbreaks in eutrophic shallow lakes. To further understand the influence of various inorganic nutrient forms on cyanobacterial blooms, a nitrate (NO3 ), ammonium (NH4 ), and orthophosphate (PO4 ) amendment experiment was conducted in a large shallow lake of China (Lake Taihu) during summer. The results showed that the photosynthetic performance of phytoplankton responded more positively to phosphorus (P) than nitrogen (N), and NH4 addition stimulated higher algal photosynthetic activities in P-enriched waters. Individual inorganic N or PO4 addition significantly activated cyanobacteria and green algae. Meanwhile, the N plus P amendment promoted higher biomass of the planktonic microbial community, and the dual addition of NH4  + PO4 yielded the highest chlorophyll a concentration. NH4 additions provisionally promoted higher green algae than cyanobacteria biomass in the beginning, while cyanobacteria dominated again with increasing NH4 :PO4 ratios. These results revealed that increasing ammonium would enhance the increase in phytoplankton biomass in advance and prolong the duration of algal blooms. Hence, based on the control of P loading, the reduction in external inorganic N focusing on ammonium sources (such as ammonia N fertilizer) at the watershed scale would help to alleviate eutrophication and cyanobacterial blooms over the long term in Lake Taihu. PRACTITIONER POINTS: Ammonium addition stimulated higher algal photosynthetic activities in P-enriched waters. Individual inorganic N or PO4 addition significantly activated cyanobacteria and green algae. The dual addition of NH4  + PO4 yielded the highest chlorophyll a concentration. Increasing NH4 would enhance the increase in phytoplankton biomass in advance and prolong the duration of cyanobacterial blooms.

Sesquiterpenes from cultures of the fungus Phellinus igniarius and their Cytotoxicities.

Four new sesquiterpenoids, phellinignins A-D (1-4), together with four known ones (5-8), were isolated from cultures of the fungus Phellinus igniarius. The structures were established by extensive spectroscopic methods including MS, NMR, and the single crystal X-ray diffraction. Compounds 1-3 and 5-8 are tremulane sesquiterpenoids, while compound 4 possesses a new carbon skeleton that might derive from an illudane framework. Compounds 1, 2, 4, and 5 showed certain cytotoxicities to three human cancer cell lines.

RETRACTED: Residual pomegranate affecting the nonspecific immunity of juvenile Darkbarbel catfish.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of Editors-in-Chief and first Author. The article duplicates significant parts of a paper that had already appeared in Fish & Shellfish Immunology, Volume 93 (2019) 726-731, https://doi.org/10.1016/j.fsi.2019.06.052. One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper has not been previously published and is not under consideration for publication elsewhere. As such this article represents a misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. The first author informed the journal that the article was published without the knowledge of the co-authors.