Zero-dimensional hybrid tin halides with stable broadband light emissions.

Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic-inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX5]3- as an emission center. Typically, [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes.

Cultivation of Chlorella vulgaris on anaerobically digested swine manure with daily recycling of the post-harvest culture broth.

In this work, a cultivation system with daily recycling of the post-harvest culture broth was set up and performed in order to reuse the water and nutrients in pretreated anaerobically digested swine manure, which was used as media to cultivate Chlorella vulgaris (UTEX 2714) at different recycling ratios. Results showed that the alga grew well in the system with an accumulative algal biomass and productivity of 1.68-3.47g/L and 234.1-532.2mg/L/d, respectively, at the end of the cultivation. Additionally, chemical compositions in this alga varied with the change of recycling ratios, and the highest productivities of carbohydrate, protein and lipids (76.4, 257.2 and 183.7mg/L/d, respectively) were obtained in the system with a recycling ratio of 1/4 or 1/6. Fatty acid profiles indicated that this alga could be used as a good-quality biodiesel feedstock with a biodiesel productivity of 9.65-40.1mg/L/d.

Growing Chlorella vulgaris on thermophilic anaerobic digestion swine manure for nutrient removal and biomass production.

Liquid swine manure was subjected to thermophilic anaerobic digestion, ammonia stripping and centrifugation in order to increase the available carbon sources and decrease the ammonia concentration and turbidity. Chlorella vulgaris (UTEX 2714) was grown on minimally diluted (2×, 3× and 4×) autoclaved and non-autoclaved pretreated anaerobic digestion swine manure (PADSM) in a batch-culture system for 7days. Results showed that C. vulgaris (UTEX 2714) grew best on 3× PADSM media, and effectively removed NH4+-N, TN, TP and COD by 98.5-99.8%, 49.2-55.4%, 20.0-29.7%, 31.2-34.0% and 99.8-99.9%, 67.4-70.8%, 49.3-54.4%, 73.6-78.7% in differently diluted autoclaved and non-autoclaved PADSM, respectively. Results of chemical compositions indicated that contents of pigment, carbohydrate, protein and lipid in C. vulgaris (UTEX 2714) changed with the culture conditions. Moreover, its fatty acid profiles suggested that this alga could be used as animal feed if cultivated in autoclaved PADSM or as good-quality biodiesel feedstock if cultivated in non-autoclaved PADSM.

Growth and physiological responses of a marine diatom (Phaeodactylum tricornutum) against two imidazolium-based ionic liquids ([C4mim]BF4 and [C8mim]BF4).

Ionic liquids (ILs) have been considered as "green" substitutes for traditional organic solvents in many existing biological and chemical areas. However, they have high solubility and poor biodegradability in water, suggesting that they could become persistent chemical pollutants in aquatic environment. The ability of two widely used imidazolium-based ILs to affect the growth and physiological characteristics of a marine diatom (Phaeodactylum tricornutum) was investigated in this study. The diatom was exposed to different concentrations of 1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim]BF4) and 1-octyl-3-methylimidazolium tetrafluoroborate ([C8mim]BF4) for 96h within a batch-culture system. Results showed that [C4mim]BF4 and [C8mim]BF4 were very stable in seawater during 96h of exposure, and the compounds significantly inhibited the growth of P. tricornutum with 24, 48, 72 and 96h EC50 values of 30.81, 28.53, 39.92, 45.88mgL-1 and 30.17, 23.36, 28.62, 31.37mgL-1, respectively. In addition, the photosynthetic activity and chlorophyll a synthesis of P. tricornutum were inhibited by [C4mim]BF4 and [C8mim]BF4, indicating that the structural integrity of chloroplasts of the diatom may be disrupted or damaged by the two ILs. Compared with that of the controls, reactive oxygen species (ROS) level was increased by 0.65, 1.17, 1.85, 3.13, 2.94 times and 0.55, 1.77, 2.42, 3.45, 3.47 times in 5, 10, 20, 40 and 60mgL-1 [C4mim]BF4 and [C8mim]BF4 treatments, respectively. The excessive ROS may cause lipid peroxidation, shortage of metabolic energy and decline of photosynthetic efficiency, which may be the main reason for toxicity of the two ILs to marine diatoms. To withstand the damaging effects of excessive ROS, remarkable physiological and biochemical responses occurred in treatments with the two ILs to protect the cells of P. tricornutum. Parameters such as soluble protein content, soluble sugar content, and superoxide dismutase (SOD) and peroxidase (POD) activities of the diatom increased significantly with increasing concentrations of the two ILs at 96h of exposure relative to the controls. These findings not only provide strong background for evaluating the ecological risks and toxicity of ILs in marine environment, but also help to unravel the toxic mechanism of the two ILs to marine diatoms.

Potential toxicity of ionic liquid ([C12mim]BF4) on the growth and biochemical characteristics of a marine diatom Phaeodactylum tricornutum.

Recently, some researchers have pointed out that the threats of ionic liquids (ILs) to aquatic environment cannot be ignored. Thus, this study investigated the potential toxicity of 1-dodecyl-3-methylimidazolium tetrafluoroborate ([C12mim]BF4) on a marine diatom Phaeodactylum tricornutum at population, biochemical and physiological levels using 96h growth tests with a batch-culture system. Results showed that [C12mim]BF4 was very stable in aquatic environment during 96h of exposure. The growth of P. tricornutum was significantly inhibited by [C12mim]BF4 with 24, 48, 72 and 96h EC50 values of 0.63, 0.61, 0.68 and 0.72mgL-1, respectively. Although there were no significant differences between the controls and treatments with 0.1 and 0.5mgL-1 [C12mim]BF4, the effective quantum yields (ΦPSII) of the diatom in 1, 2.5, 5 and 10mgL-1 [C12mim]BF4 treatments were 61.48, 17.04, 2.96 and 0.74% of that in the controls at 96h of exposure, respectively. Chl a content of the diatom was decreased by 34.86, 47.79, 49.81, 59.21, 79.82 and 86.98% compared with that of the controls at 96h of exposure in 0.1, 0.5, 1, 2.5, 5 and 10mgL-1 [C12mim]BF4 treatments, respectively. Relative to the controls, soluble sugar content, reactive oxygen species (ROS) level, malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) activities of the diatom increased with increasing [C12mim]BF4 concentrations at 96h of exposure, and reached their maxima (1.46µg106cell-1, 7.48FU107cell-1, 3.35nmol108cell-1, 33.41 and 7.23Umg-1 proteins, respectively) in 5mgL-1 [C12mim]BF4 treatments. While the maximum soluble protein content (1.56µg106cell-1) of the diatom was obtained in 0.5mgL-1 [C12mim]BF4 treatments, and then decreased with increasing [C12mim]BF4 concentrations from 0.5 to 10mgL-1. These findings provide strong evidence for the potential toxicity of ILs to marine diatoms.

Biological effects of TiO2 and CeO2 nanoparticles on the growth, photosynthetic activity, and cellular components of a marine diatom Phaeodactylum tricornutum.

It is very important to have a good understanding of the biological effects of nanoparticles (NPs) on marine diatoms. In this study, the physiological and biochemical responses of a marine diatom Phaeodactylum tricornutum to titanium dioxide NPs (nano-TiO2) and cerium oxide NPs (nano-CeO2) were compared and evaluated using 96h growth tests in a batch-culture system. At 96h of exposure, the growth inhibition rate (IR, %) of P. tricornutum increased from 5.46 to 27.31% with increasing nano-TiO2 concentrations from 2.5 to 40mgL-1. The maximum IR of 49.59% occurred in 40mgL-1 nano-TiO2 treatments at 48h of exposure. Growth of the diatom was increased in low nano-CeO2 treatments (≤5mgL-1), but was inhibited in high nano-CeO2 treatments (≥10mgL-1). Large aggregates of NPs were attached to the cells of P. tricornutum in 20 and 40mgL-1 nano-TiO2 and nano-CeO2 treatments. In addition, the effective quantum yields (ΦPSII) of P. tricornutum in 40mgL-1 nano-TiO2 and nano-CeO2 treatments were 83.33 and 71.13% of that in the controls at 96h of exposure, respectively. Compared with that of the controls at 96h of exposure, chlorophyll a content, soluble sugar content, malondialdehyde (MDA) content, SOD and POD activities of P. tricornutum in 40mgL-1 nano-TiO2 and nano-CeO2 treatments increased by 57.56, 142.97, 373.25, 698.76, 204.85% and 21.43, 89.41, 194.97, 340.05, 502.86%, while soluble protein content decreased by 70.38 and 28.64%, respectively. These findings will be helpful to understand the effect mechanisms of NPs on marine organisms.

iTRAQ-based quantitative proteomic analysis of midgut in silkworm infected with Bombyx mori cytoplasmic polyhedrosis virus.

Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) specifically infects the epithelial cells in the midgut of silkworm and causes them to death, which negatively affects the sericulture industry. In order to determine the midgut response at the protein levels to the virus infection, differential proteomes of the silkworm midgut responsive to BmCPV infection were identified with isobaric tags for relative and absolute quantitation (iTRAQ) labeling followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). 193, 408, 189 differentially expressed proteins (DEPs) were reliably quantified by iTRAQ analysis in the midgut of BmCPV-infected and control larvae at 24, 48, 72h post infection (hpi) respectively. KEGG enrichment analysis showed that Oxidative phosphorylation, amyotrophic lateral sclerosis, Toll-like receptor signaling pathway, steroid hormone biosynthesis were the significant pathways (Q value≤0.05) both at 24 and 48hpi. qRT-PCR was used to further verify gene transcription of 30 DEPs from iTRAQ, showing that the regulations of 24 genes at the transcript level were consistent with those at the proteomic level. Moreover, the cluster analysis of the three time groups showed that there were seven co-regulated DEPs including BGIBMGA002620-PA, which was a putative p62/sequestosome-1 protein in silkworm. It was upregulated at both the mRNA level and the proteomic level and may play an important role in regulating the autophagy and apoptosis (especially apoptosis) induced by BmCPV infection. This was the first report using an iTRAQ approach to analyze proteomes of the silkworm midgut against BmCPV infection, which contributes to understanding the defense mechanisms of silkworm midgut to virus infection. SIGNIFICANCE: The domesticated silkworm, Bombyx mori, is renowned for silk production as well as being a traditional lepidopteron model insect served as a subject for morphological, genetic, physiological, and developmental studies. Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) specifically infects the epithelial cells in the midgut of silkworm and causes the silkworm to death, which negatively affects the sericulture industry. Studies on insect antiviral immunity and on interactive mechanisms between host cells and BmCPV are in their infancy and remain insufficient. In order to obtain an overall view of silkworm response to BmCPV infection, we performed a proteomic analysis of the midgut of silkworm responses to BmCPV infection by iTRAQ. This was the first report using an iTRAQ approach to analyze proteomes of the silkworm midgut against BmCPV infection, which contributes to understanding the defense mechanisms of silkworm midgut to virus infection.

Growth inhibition and oxidative stress induced by 1-octyl-3-methylimidazolium bromide on the marine diatom Skeletonema costatum.

Marine diatom Skeletonema costatum is an important prey in the marine food web and is often used as a standard test organism in ecotoxicological studies. In this study, in vivo experiments were performed to analyze the effects of 1-octyl-3-methylimidazolium bromide ([C8mim]Br) on the growth, photosynthetic activity, and oxidative stress in S. costatum using 96h growth tests with a batch-culture system. The growth of S. costatum was significantly inhibited by [C8mim]Br with 48 and 96h-EC50 of 17.9 and 39.9mgL(-1), respectively. The maximum quantum yield (Fv/Fm) and the light use efficiency (α) were inhibited by [C8mim]Br, which affected the growth of S. costatum. Subsequent biochemical assays in S. costatum revealed that [C8mim]Br induced changes of Chl a content, soluble protein content, and SOD activity, which had significant increases in low [C8mim]Br treatments (≤20mgL(-1)), but decreased in high [C8mim]Br exposures (≥40mgL(-1)). The increase of SOD activity at low concentrations (≤20mgL(-1)) may be considered as an active defense of S. costatum against [C8mim]Br stress by reactive oxygen species (ROS) quenching. In addition, [C8mim]Br increased ROS level and malondialdehyde (MDA) content in S. costatum, suggesting that the physiological effects of [C8mim]Br are resulted from ROS generation.

Process development for scum to biodiesel conversion.

A novel process was developed for converting scum, a waste material from wastewater treatment facilities, to biodiesel. Scum is an oily waste that was skimmed from the surface of primary and secondary settling tanks in wastewater treatment plants. Currently scum is treated either by anaerobic digestion or landfilling which raised several environmental issues. The newly developed process used a six-step method to convert scum to biodiesel, a higher value product. A combination of acid washing and acid catalyzed esterification was developed to remove soap and impurities while converting free fatty acids to methyl esters. A glycerol washing was used to facilitate the separation of biodiesel and glycerin after base catalyzed transesterification. As a result, 70% of dried and filtered scum was converted to biodiesel which is equivalent to about 134,000 gallon biodiesel per year for the Saint Paul waste water treatment plant in Minnesota.

Cloning and expression analysis of a peptidoglycan recognition protein in silkworm related to virus infection.

In this study, the full-length cDNA of a peptidoglycan recognition protein named BmPGRP-S3 was identified from the silkworm, Bombyx mori by rapid amplification of cDNA ends. It is 807 bp and comprises the following: a 5'-untranslated region (UTR) with a length of 112 bp, a 3'-UTR with a length of 92 bp including a poly-adenylation signal sequence (AATAAA) and a poly(A) tail. The longest open reading frame (ORF) of BmPGRP-S3 is 603 bp and encodes a polypeptide of 200 amino acids with a predicted molecular weight of 22.3 kDa including a PGRP domain. Sequence similarity and phylogenic analysis results indicated that BmPGRP-S3 belongs to the group of insect PGRPs and is closer to BmPGRP-S4 with the highest identity of 68%. Fluorescent quantitative real-time PCR results revealed that the mRNA transcripts of BmPGRP-S3 were presented in all of the tissues, but were highest in the midgut. In the silkworm larvae infected with B. mori cytoplasmic polyhedrosis virus (BmCPV), the relative expression level of BmPGRP-S3 was upregulated. The DNA segment of a mature BmPGRP-S3 peptide was inserted into the expression plasmid pET-28a(+) to construct a recombinant expression plasmid. Western blot results revealed that mature BmPGRP-S3 could be detected in the hemolymph and midgut which were the most important immune tissues in silkworm. All the results suggested that BmPGRP-S3 may play an important role in the immune response of silkworm to BmCPV infection and provided helpful information for further studying the function of BmPGRP-S3 in silkworm.

Cytoplasmic polyhedrosis virus-induced differential gene expression in two silkworm strains of different susceptibility.

Digital gene expression (DGE) was performed to investigate the gene expression profiles of 4008 and p50 silkworm strains at 48 h after oral infection with BmCPV. 3,668,437 clean tags were identified in the BmCPV-infected p50 silkworms and 3,540,790 clean tags in the control p50. By contrast, 4,498,263 clean tags were identified in the BmCPV-infected 4008 silkworms and 4,164,250 clean tags in the control 4008. A total of 691 differentially expressed genes were detected in the infected 4008 DGE library and 185 were detected in the infected p50 DGE library, respectively. The expression profiles identified some important differentially expressed genes involved in signal transduction, enzyme activity and apoptotic changes, some of which were verified using quantitative real-time PCR (qRT-PCR). These results provide important clues on the molecular mechanism of BmCPV invasion and resistance mechanism of silkworms against BmCPV infection.

Digital gene expression analysis in the midgut of 4008 silkworm strain infected with cytoplasmic polyhedrosis virus.

Digital Gene Expression was performed to investigate the midgut transcriptome profile of 4008 silkworm strain orally infected with BmCPV. A total of 4,498,263 and 4,258,240 clean tags were obtained from the control and BmCPV-infected larvae. A total of 752 differentially expressed genes were detected, of which 649 were upregulated and 103 were downregulated. Analysis results of the Kyoto Encyclopedia of Genes and Genomes pathway showed that 334 genes were involved in the ribosome and RNA transport pathways. Moreover, 408 of the 752 differentially expressed genes have a GO category and can be categorized into 41 functional groups according to molecular function, cellular component and biological process. Differentially expressed genes involved in signaling, gene expression, metabolic process, cell death, binding, and catalytic activity changes were detected in the expression profiles. Quantitative real-time PCR was performed to verify the expression of these genes. The upregulated expression levels of Calreticulin, FK506-binding protein, and protein kinase c inhibitor gene probably led to a calcium-dependent apoptosis in the BmCPV-infected cells. The results of this study may serve as a basis for future research not only on the molecular mechanism of BmCPV invasion but also on the anti-BmCPV mechanism of silkworm.

cDNA cloning and characterization of LASP1 from silkworm, Bombyx mori, involved in cytoplasmic polyhedrosis virus infection.

Full-length cDNA of a LIM and SH3 contained protein 1 (named BmLASP1) was identified from the silkworm, Bombyx mori, for the first time by rapid amplification of cDNA ends. The full-length cDNA of BmLASP1 is 2094 bp, consisting of a 5'-terminal untranslated region (UTR) of 117 bp, and a 3'-UTR of 610 bp with two poly-adenylation signal sequence AATAAA and a poly (A) tail. The BmLASP1 cDNA encodes a polypeptide comprising 455 amino acids, including a LIM domain, two nebulin domains and an SH3 domain. The theoretical isoelectric point is 7.07 and the predicted molecular weight is 51.8 kDa. BmLASP1 has no signal peptide but three potential N-glycosylation sites. Sequence similarity and phylogenic analyses indicated that BmLASP1 belonged to the group of insect LASP1 with a longer linker region which is different from vertebrate LASP1. The LASP1 in silkworm contained eight exons in its coding regions, and the last exon-intron boundary was conserved the same as in mammalian and Ciona intestinalis LASP1 genes. By fluorescent quantitative real-time polymerase chain reaction, the mRNA transcripts of BmLASP1 were mainly detected in the gonad, head, and spiracle, and slightly in the silk gland, vasa mucosa, midgut, fat body, and hemocytes. After silkworm larvae were infected by B. mori cytoplasmic polyhedrosis virus (BmCPV), the relative expression level of BmLASP1 was down-regulated in the midgut. This result suggested that BmLASP1 may play an important role in the response of silkworm to BmCPV infection.

Novel protein of IBP from silkworm, Bombyx mori, involved in cytoplasmic polyhedrosis virus infection.

In the present study, the full-length cDNA of a novel insulin-related peptide-binding protein (named BmIBP2) was identified from silkworm, Bombyx mori, using rapid amplification of cDNA ends. The full-length cDNA of BmIBP2 is 1293 bp, consisting of a 5'-terminal untranslated region (UTR) of 61 bp, and a 3'-UTR of 335 bp with a poly-adenylation signal sequence AATAAA and a poly (A) tail. The BmIBP2 cDNA encodes a polypeptide of 298 amino acids, including an IG domain and an IGc2 domain, with a theoretical isoelectric point of 5.73 and a predicted molecular weight of 33.1 kDa. The BmIBP2 also has a signal peptide of 23 amino acids and a potential N-glycosylation site. The sequence similarity and phylogenic analysis indicated that BmIBP2 belongs to the group of invertebrates IBP and is closer to IGFBP7 than to the other IGFBPs in vertebrates. These findings suggest that BmIBP2 is a putative homolog of vertebrate endocrine factor IGFBP7 and has a functional similarity. By fluorescent quantitative real-time polymerase chain reaction, mRNA transcripts of BmIBP2 were mainly detected in the midgut but were hardly detectable in the hemocytes, vasa mucosa, fat body, silk gland, head, testicle, ovary, and spiracle. After the silkworm larvae were infected by B. mori cytoplasmic polyhedrosis virus (BmCPV), a significant up-regulation in the relative expression level of BmIBP2 was found. All the results suggested that BmIBP2 is a novel protein that plays an important role in the insulin-signal pathway and in the immune response of silkworm to BmCPV infection.