UV-A radiation increases biomass yield by enhancing energy flow and carbon assimilation in the edible cyanobacterium Nostoc sphaeroides.

Ultraviolet (UV) A radiation (315-400 nm) is the predominant component of solar UV radiation that reaches the Earth's surface. However, the underlying mechanisms of the positive effects of UV-A on photosynthetic organisms have not yet been elucidated. In this study, we investigated the effects of UV-A radiation on the growth, photosynthetic ability, and metabolome of the edible cyanobacterium Nostoc sphaeroides. Exposures to 5-15 W m-2 (15-46 µmol photons m-2 s-1) UV-A and 4.35 W m-2 (20 µmol photons m-2 s-1) visible light for 16 days significantly increased the growth rate and biomass production of N. sphaeroides cells by 18%-30% and 15%-56%, respectively, compared to the non-UV-A-acclimated cells. Additionally, the UV-A-acclimated cells exhibited a 1.8-fold increase in the cellular nicotinamide adenine dinucleotide phosphate (NADP) pool with an increase in photosynthetic capacity (58%), photosynthetic efficiency (24%), QA re-oxidation, photosystem I abundance, and cyclic electron flow (87%), which further led to an increase in light-induced NADPH generation (31%) and ATP content (83%). Moreover, the UV-A-acclimated cells showed a 2.3-fold increase in ribulose-1,5-bisphosphate carboxylase/oxygenase activity, indicating an increase in their carbon-fixing capacity. Gas chromatography-mass spectrometry-based metabolomics further revealed that UV-A radiation upregulated the energy-storing carbon metabolism, as evidenced by the enhanced accumulation of sugars, fatty acids, and citrate in the UV-A-acclimated cells. Therefore, our results demonstrate that UV-A radiation enhances energy flow and carbon assimilation in the cyanobacterium N. sphaeroides.IMPORTANCEUltraviolet (UV) radiation exerts harmful effects on photo-autotrophs; however, several studies demonstrated the positive effects of UV radiation, especially UV-A radiation (315-400 nm), on primary productivity. Therefore, understanding the underlying mechanisms associated with the promotive effects of UV-A radiation on primary productivity can facilitate the application of UV-A for CO2 sequestration and lead to the advancement of photobiological sciences. In this study, we used the cyanobacterium Nostoc sphaeroides, which has an over 1,700-year history of human use as food and medicine, to explore its photosynthetic acclimation response to UV-A radiation. As per our knowledge, this is the first study to demonstrate that UV-A radiation increases the biomass yield of N. sphaeroides by enhancing energy flow and carbon assimilation. Our findings provide novel insights into UV-A-mediated photosynthetic acclimation and provide a scientific basis for the application of UV-A radiation for optimizing light absorption capacity and enhancing CO2 sequestration in the frame of a future CO2 neutral, circular, and sustainable bioeconomy.

Cationic Nanoparticle-Stabilized Vaccine Delivery System for the H9N2 Vaccine to Promote Immune Response in Chickens.

Chinese yam polysaccharides (CYPs) have received wide attention for their immunomodulatory activity. Our previous studies had discovered that the Chinese yam polysaccharide PLGA-stabilized Pickering emulsion (CYP-PPAS) can serve as an efficient adjuvant to trigger powerful humoral and cellular immunity. Recently, positively charged nano-adjuvants are easily taken up by antigen-presenting cells, potentially resulting in lysosomal escape, the promotion of antigen cross-presentation, and the induction of CD8 T-cell response. However, reports on the practical application of cationic Pickering emulsions as adjuvants are very limited. Considering the economic damage and public-health risks caused by the H9N2 influenza virus, it is urgent to develop an effective adjuvant for boosting humoral and cellular immunity against influenza virus infection. Here, we applied polyethyleneimine-modified Chinese yam polysaccharide PLGA nanoparticles as particle stabilizers and squalene as the oil core to fabricate a positively charged nanoparticle-stabilized Pickering emulsion adjuvant system (PEI-CYP-PPAS). The cationic Pickering emulsion of PEI-CYP-PPAS was utilized as an adjuvant for the H9N2 Avian influenza vaccine, and the adjuvant activity was compared with the Pickering emulsion of CYP-PPAS and the commercial adjuvant (aluminum adjuvant). The PEI-CYP-PPAS, with a size of about 1164.66 nm and a ζ potential of 33.23 mV, could increase the H9N2 antigen loading efficiency by 83.99%. After vaccination with Pickering emulsions based on H9N2 vaccines, PEI-CYP-PPAS generated higher HI titers and stronger IgG antibodies than CYP-PPAS and Alum and increased the immune organ index of the spleen and bursa of Fabricius without immune organ injury. Moreover, treatment with PEI-CYP-PPAS/H9N2 induced CD4+ and CD8+ T-cell activation, a high lymphocyte proliferation index, and increased cytokine expression of IL-4, IL-6, and IFN-γ. Thus, compared with the CYP-PPAS and aluminum adjuvant, the cationic nanoparticle-stabilized vaccine delivery system of PEI-CYP-PPAS was an effective adjuvant for H9N2 vaccination to elicit powerful humoral and cellular immune responses.

Effects of Alhagi Honey Polysaccharides as Feed Supplement on Intestine Function and Microbiome, Immune Function, and Growth Performance in Chicken.

Hy-Line Brown chickens' health is closely related to poultry productivity and it is mainly maintained by the immune system, healthy intestinal function, and microflora of chicken. Polysaccharides are biological macromolecules with a variety of activities that can be used as a potential prebiotic to improve poultry health. In this experiment, the function of Alhagi honey polysaccharides (AH) as an immunomodulator on the chicken was investigated. All chicken (120) were randomly distributed to four groups (five replicas/group, six hens/replica). A total of 0.5 mL water was taken orally by the chicken in control group. AH (0.5 mL) in different concentrations (three dosages, 0.3 g/kg, 0.6 g/k, and 1.2 g/kg) were used for the AH-0.3 g/kg, AH-0.6 g/k, and AH-1.2 g/kg group, respectively. The results showed that the growth performance of the chickens and the index of immune organs (the weight of immune organs/the body weight) were enhanced significantly after being AH-treated (p < 0.05). The content of sIgA and cytokines was upregulated remarkably in the intestine after being AH-treated (p < 0.05). The AH treatment significantly enhanced the intestinal epithelial barrier (p < 0.05). Moreover, the percentage of CD4+ and CD8+ T cells in the ileum, spleen, and serum were obviously upscaled (p < 0.05). In addition, the AH treatment significantly enhanced the production of short chain fatty acids (SCFAs) and improved the structure of gut microbiota (p < 0.05). In conclusion, we found that AH-1.2g/kg was the best dosage to improve the chicken's health, and these data demonstrated that AH could be used as a potential tool to enhance growth performance through improving intestine function, immunity, and gut microbiome in chicken.

Detection of viable and total fungal community in zaopei of Chinese strong-flavor baijiu using PMA combined with qPCR and HTS based on ITS2 region.

BACKGROUND: Chinese strong-flavor baijiu (CSFB), one of the three major baijiu types, is the most popular baijiu type among consumers in China. A variety of microbes are involved in metabolizing raw materials to produce ethanol and flavor substances during fermentation, which fundamentally determined the quality of baijiu. It is of great importance to study microbial community of fermented grains (zaopei) during baijiu brewing process for improving its quality. In this study, we firstly used propidium monoazide (PMA) to treat zaopei samples from 5-year pit and 20-year pit for removing the interference of non-viable fungi, and analyzed the diversity of total fungi and viable fungi by quantitative PCR (qPCR) and high-throughput sequencing (HTS) based on ITS2 gene. RESULTS: The results showed that total fungi and viable fungi displayed no significant differences at OTU, phylum, or genus levels during fermentation within two kinds of pits. A total of 6 phyla, 19 classes, and 118 genera in fungi were found based on OTUs annotation in zaopei samples from 5-year pit and 20-year pit. Besides, non-viable fungi had little effect on the fungal community diversity during the fermentation cycle. It was found that the most dominant viable fungi belonged to Saccharomyces, Kazachstania, Naumovozyma, and Trichosporon, and Naumovozyma was firstly detected in zaopei samples of CSFB. Moreover, based on the variation of flavor substances in zaopei samples, the quality of CSFB produced from older pit was better than that produced from younger pit. CONCLUSION: The non-viable fungi had little effect on the fungal diversity, structure, and relative abundance in zaopei samples of CSFB, and Naumovozyma was firstly detected in zaopei samples of CSFB. Our findings can be applied as guidance for improving the quality and stability of CSFB.

Administration Routes of Polyethylenimine-Coated PLGA Nanoparticles Encapsulating Angelica Sinensis Polysaccharide Vaccine Delivery System Affect Immune Responses.

Nanoparticle vaccine delivery systems have been emerging strategies for inducing potent immune responses to prevent and treat infectious diseases and cancers. The properties of nanoparticle vaccine delivery systems, such as nanoparticle size, surface charge, and antigen release kinetics, have been extensively studied and proven to effectively influence the efficacy of vaccine responses. However, a few types of research have focused on the influence of administration routes of nanoparticle vaccines on immune responses. Herein, to investigate how the administration routes affect the immune responses of nanoparticles vaccines, we developed a nanoparticles system (NPs), in which the ovalbumin (OVA) and Angelica sinensis polysaccharide (ASP) were incorporated into poly(lactic-co-glycolic acid) (PLGA) nanoparticles and the polyethylenimine (PEI) was coated on the surface of nanoparticles. The NPs vaccine was intramuscularly and subcutaneously injected (im and sc) into mice, and the immune responses induced by these two delivery routes were compared. The results showed that both im and sc administration of NPs vaccines elicited strong antigen-specific IgG, IgG1, and IgG2a antibody responses, with no significant difference. In contrast, NP vaccines with sc administration significantly enhanced immune responses, such as enhancing the recruitment and activation of dendritic cells (DCs) in lymph nodes (LNs), promoting the antigen transport into draining lymph nodes, increasing the secretion of cytokines, improving the ratio of CD4+T cells to CD8+ T cells, activating cytotoxic T lymphocyte response, and inducing a strong cellular immune response. These results may provide a new insight onto the development of vaccine delivery systems.

A Novel Nanomedicine Ameliorates Acute Inflammatory Bowel Disease by Regulating Macrophages and T-Cells.

Ramulus mori polysaccharide (RMP), one of the most important active components of R. mori, has been attracting increasing interest because of its potent bioactive properties, including anti-inflammatory, antitumor, and antidiabetic effects. Despite the great therapeutic potential of RMP, its inherent properties of low bioavailability and brief biological half-life have limited its applications to the clinic. Thus, RMP was packaged by poly(lactic-co-glycolic acid) (PLGA) nanoparticles to develop a novel anti-inflammatory nanomedicine (PLGA-RMP) in this study. The nanoparticles were synthesized via a double-emulsion solvent evaporation technique, and the average diameter of PLGA-RMP was about 202 nm. PLGA-RMP nanoparticles reduced the expression of inflammatory cytokines while promoting the production of IL-10, and boosted the phenotypic shift in macrophages in vitro. Furthermore, lipopolysaccharide (LPS)-induced inflammatory bowel disease (IBD) in mouse was used to examine the anti-inflammatory effect of PLGA-RMP in vivo. Oral administration of PLGA-RMP in LPS-induced IBD mice substantially mitigated the intestinal inflammation compared to treatment with LPS alone, as evidenced by attenuation of disease activity index scores and inflammatory damage in the intestine. Meanwhile, PLGA-RMP suppressed the expression and secretion of specific inflammatory cytokines including TNF-α, IL-6, IL-1ß, and PGE2 in the inflamed intestine while inhibiting the activation of CD3+CD8+ T-cells and increasing the number of activated Tregs in the intestine. These results indicated that PLGA-RMP deserves further consideration as a potential therapeutic nanomedicine to treat various inflammatory diseases, including IBD.

Pararcticibacter amylolyticus gen. nov., sp. nov., Isolated from a Rotten Hemp Rope, and Reclassification of Pedobacter tournemirensis as Pararcticibacter tournemirensis comb. nov.

A Gram-stain-negative, rod-shaped, non-motile, facultatively anaerobic bacterium, designated FJ4-8T, was isolated from a rotten hemp rope in Chongqing City, PR China. Phylogenetic analysis of 16S rRNA gene sequences indicated that the isolate was closely related to members of the family Sphingobacteriaceae, with the highest similarity to Pedobacter tournemirensis TF5-37.2-LB10T (95.3%) and low similarities to all other species of the genus Pedobacter (90.4-93.9%). Phylogenetic analyses demonstrated that strain FJ4-8T formed a stable subclade with Pedobacter tournemirensis TF5-37.2-LB10T. The clade with these two strains branched adjacent to a clade containing three species of the genus Arcticibacter. MK-7 was detected as the only respiratory quinone. The major fatty acids composed iso-C15:0, iso-C17:0 3-OH and summed feature three. Phosphatidylethanolamine, three aminophospholipids and one unidentified lipid were found as the major polar lipids. The major polyamine was identified as sym-homospermidine. The DNA-DNA hybridization value between strain FJ4-8T and Pedobacter tournemirensis TF5-37.2-LB10T was 42.0 ± 2.5%. Based on its phylogenetic, chemotaxonomic and phenotypic characteristics, the novel strain and TF5-37.2-LB10T were found to be different from members of genera Pedobacter and Arcticibacter. FJ4-8T and TF5-37.2-LB10T represented different species. Therefore, FJ4-8T should be classified as a novel species of a novel genus in the family Sphingobacteriaceae, for which the name Pararcticibacter amylolyticus gen. nov., sp. nov. is proposed. The type strain is FJ4-8T (= KCTC 62640T = CCTCC AB 2018052T). The draft genome sequence is 6290, 449 bp in length, the genomic DNA G+C content was 44.4 mol%. Pedobacter tournemirensis TF5-37.2-LB10T should be transferred to the novel genus as Pararcticibacter tournemirensis comb. nov. (The type strain is TF5-37.2-LB10T (= DSM 23085T = CIP 110085T = MOLA 820T).

Rational Design of PLGA Nanoparticle Vaccine Delivery Systems To Improve Immune Responses.

Nanoparticle-based vaccine delivery systems have been extensively used to promote and induce immune responses to protein antigens. The properties of the nanoparticles, such as size, surface charge, and antigen loading mode, have been proved to significantly influence the adjuvant effect and immunoreactivity of nanoparticle-based vaccine delivery systems. The purpose of the study was to investigate how the surface charge and antigen loading mode of nanoparticles impact the immune responses. In this study, three ovalbumin (OVA)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles with different surface charges and antigen loading modes were developed. The three nanoparticles were designed as antigen encapsulated with negatively charged (Angelica sinensis polysaccharide (ASP)-PLGA/OVA), antigen encapsulated with polyethylenimine (PEI)-coated (ASP-PLGA/OVA-PEI), and antigen adsorbed on PEI-coated (ASP-PLGA-PEI-OVA) nanoparticles. The Angelica sinensis polysaccharide (ASP) was used as the immunopotentiator and encapsulated into three nanoparticles. The results demonstrated that both PEI-coated (positively charged) nanoparticles promoted the antigen escape from the endosome, which led to the cytoplasmic antigen delivery to generate cross presentation, compared to negatively charged nanoparticles. In addition, PEI-coated nanoparticles activated the DCs in lymph nodes 5 days after the primary vaccination. In vivo experiments demonstrated that both antigen-encapsulated nanoparticles induced more potent and long-term antigen-specific antibody responses, compared to that of antigen-adsorbed nanoparticles. Thus, the PEI-coated and antigen-encapsulated nanoparticles (ASP-PLGA/OVA-PEI) as a vaccine adjuvant delivery system have the potential to induce strong and long-term humoral and cellular immune responses.

Assessment of the hepatocyte protective effects of gypenoside and its phosphorylated derivative against DHAV-1 infection on duck embryonic hepatocytes.

BACKGROUND: Duck viral hepatitis (DVH) is an acute disease of young ducklings with no effective veterinary drugs for treatment. Gynostemma pentaphyllum is a well-known traditional Chinese medicine that plays an important role in the treatment of various diseases. Gypenoside (GP), one of the main ingredients of Gynostemma pentaphyllum, was reported with good hepatoprotective effects. However, its low solubility limits its application in the clinics. To improve its solubility and bioactivity, a phosphorylated derivative of gypenoside (pGP) was prepared by the sodium trimetaphosphate-sodium tripolyphosphate (STMP-STPP) method. An infrared spectroscopy method was applied to analyse the structures of GP and pGP. Then, a methyl thiazolyl tetrazolium (MTT) colorimetric assay was applied to study the hepatocyte protective efficacy of these two drugs against duck hepatitis A virus type 1 (DHAV-1) infection, and qPCR, TUNEL labelling and flow cytometry methods were used to study the relevant hepatocyte protective in vitro. RESULTS: The infrared spectroscopy detection results showed that the phosphorylation modification of GP was successful. The MTT colorimetric assay results showed that both GP and pGP possessed good hepatocyte protective efficacy in vitro, and pGP performed better than GP when the drug was added before or after virus inoculation. Furthermore, the qPCR results revealed that both drugs could effectively inhibit the adsorption (when adding GP and pGP pre-virus inoculation), replication and release of DHAV-1, and the viral inhibition rate of pGP was greater than that of GP. The subsequent TUNEL labelling and flow cytometry assays showed that both GP and pGP could significantly inhibit duck embryo hepatocyte apoptosis induced by DHAV-1, and the inhibition effect of pGP was much stronger than that of GP. CONCLUSIONS: GP exerts good hepatocyte protective efficacy not only by inhibiting the proliferation of DHAV-1 but also by inhibiting duck embryonic hepatocyte apoptosis induced by DHAV-1, and phosphorylation modification significantly improves the antiviral and the anti-apoptotic effects of GP. Therefore, pGP has the potential to be developed into a novel drug against DHAV-1 infection.

Efficient production of succinic acid in engineered Escherichia coli strains controlled by anaerobically-induced nirB promoter using sweet potato waste hydrolysate.

Succinic acid has attracted interest worldwide as a precursor of many industrially crucial chemicals. Biosynthesis of succinic acid from biomass is developing as an environmentally friendly strategy now. Conversion of sweet potato waste (SPW) to succinic acid could implement high-value utilization of biomass, cut cost of the fermentation process and reduce the pollution of environment. Engineered Escherichia coli (E. coli) strain HD134 under the control of anaerobically-induced nirB promoter from Salmonella enterica (PSnirB) could produce about 16.30 g/L succinic acid with a yield of 0.83 g/g after 48 h on glucose. With SPW hydrolysate as the substrate, 18.65 g/L succinic acid with a yield of 0.94 g/g after 48 h fermentation achieved. Compared to SD134 under Trc control induced with Isopropyl ß-D-Thiogalactoside (IPTG), this concentration and yield represented an 8.56% and 6.82% increase, respectively. The use of anaerobically-induced PSnirB not only could attain higher production of succinic acid than IPTG-induced Trc promoter, but omit cost of expensive exogenous inducers. The efficient production of succinic acid from SPW was firstly studied by anaerobically-induced PSnirB control, which achieved relative lower cost compared to glucose as substrate and IPTG as the inducer. This novel fermentation process conduces to the cosmically industrial succinic acid bioproduction.

Anti-DHAV-1 reproduction and immuno-regulatory effects of a flavonoid prescription on duck virus hepatitis.

CONTEXT: The flavonoid prescription baicalin-linarin-icariin-notoginsenoside R1 (BLIN) has a curative effect on duck virus hepatitis (DVH) caused by duck hepatitis A virus type 1 (DHAV-1). However, the mechanism of this curative effect is not understood. OBJECTIVE: This study investigates the mechanism of the curative effect of BLIN on DVH caused by DHAV-1. We analyzed the anti-DHAV-1 reproduction mechanism and immuno-regulatory effect of BLIN. MATERIALS AND METHODS: The anti-DHAV-1 reproduction effects of BLIN at 20, 10, 5 and 2.5 µg/mL in vitro, as well as the influence of BLIN at 20 µg/mL on DHAV-1 adsorption, replication and release were tested using the qRT-PCR method. The promotion abilities of BLIN at 20, 10, 5 and 2.5 µg/mL on T- and B-lymphocyte proliferation were investigated by the MTT method. IL-2 and IFN-γ levels and total anti-DHAV-1 antibody secretion after treatment with DHAV-1 for 4, 8 and 54 h were determined by ELISA. RESULTS: BLIN showed a dose-dependent DHAV-1 reproduction inhibitory effect. The inhibitory effect was highest at 20 µg/mL, where DHAV-1 adsorption and release were significantly lower. Meanwhile, BLIN at 5 µg/mL significantly increased T and B lymphocyte proliferation. BLIN stimulated total anti-DHAV-1 antibody secretion in ducklings at the dosage of 4 mg per duckling, but did not stimulate IL-2 and IFN-γ secretion significantly. CONCLUSIONS: BLIN inhibits DHAV-1 reproduction by suppressing its adsorption and release. Additionally, BLIN promoted the duckling antiviral response.

[Effects of Neurotrophin Receptor-interacting MAGE Homolog on Apoptosis of Intestinal Epithelial Cells].

OBJECTIVE: To explore whether neurotrophin receptor-interacting MAGE homolog (NRAGE) is involved in the intestinal ischemia-reperfusion (I/R) and its effect on the apoptosis of intestinal epithelial cells and the expression of occludin protein. METHODS: The level of NRAGE protein after the rat small intestine I/R was detected by immunohistochemical (IHC) In vivo. The level of NRAGE protein and mRNA in IEC-6 cells after hypoxia and reoxygenation were tested by Western blot and RT-PCR respectively in vitro. The IEC-6 cells were divided into four groups, including NRAGE overexpression by lentivirus infection (Lv-NRAGE group), interference (sh-NRAGE group), lentivirus control (Lv-control group), and normal control group without lentivirus infection (NC group). The apoptosis of IEC-6 cells after infection was analyzed by flow cytometry. The level of the tight junction protein occludin was detected by Western blot. RESULTS: The expression of NRAGE were highly increased in intestinal mucosa epithelial cells after I/R (P<0.01). The proteins and mRNA levels of NRAGE were increased after 6 h of hypoxia in IEC-6 cellsin vitro. Compared with the Lv-control group, the early apoptosis rate was raised (P<0.01) and the level of occludin was reduced (P<0.01) in Lv-NRAGE group; while the early apoptosis rate was reduced (P<0.01) and the level of occludin was raised in sh-NRAGE group(P<0.001). CONCLUSION: NRAGE may be involved in intestinal I/R and promote the apoptosis and decrease occludin expression of intestinal epithelial cells.

Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity.

Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

Determine the structure of phosphorylated modification of icariin and its antiviral activity against duck hepatitis virus A.

BACKGROUND: Our previous research showed that icariin (1) and its phosphorylated structural modification (2) improved the survival and attenuated oxidative stress and liver dysfunction induced by duck virus hepatitis. In this paper, we were one step closer to determine the structure of phosphorylation icariin (2) by the FT-IR, HRESIMS and (13)C NMR. Anti-DHAV activities of 1 and 2 were compared in duck embryonic hepatocytes (DEHs) cultured in vitro and by artificial infection method in vivo. Additionally, the antiviral mechanisms of replication/release in vitro and the DHAV gene expression in vivo of 1 and 2 were analyzed. RESULTS: Compound 2's molecular formula was C33H42O18P. The results indicated that 1 and 2 effectively resisted DHAV invading DEHs, that they decreased the mortality of ducklings challenged with DHAV, and that 2 performed more effectively. 1 and 2 performed evenly on DHAV release; however, 2 restrained virus replication far more effectively. Since the anti-DHAV mechanisms of 1 and 2 in vitro probably involve suppression of replication and release, 2's better performance in anti-DHAV may result from its far more effectively inhibiting virus replication. CONCLUSIONS: The compound 2's chemical structure was defined as 8-prenylkaempferol-4'-methylether-3-rhamnosyl-7-(6'''-phosphate)-glycoside. 1 and 2 exhibited anti-virus activity on DHAV. Our results suggest that 1 and 2 might become an anti-virus plant material candidate.

Effects of Bacillus subtilis KN-42 on Growth Performance, Diarrhea and Faecal Bacterial Flora of Weaned Piglets.

This research focused on the effects of different doses of Bacillus subtilis KN-42 on the growth performance, diarrhea incidence, faecal bacterial flora, and the relative number of Lactobacillus and Escherichia coli in faeces of weaned piglets to determine whether the strain can serve as a candidate antimicrobial growth promoter. A total of 360 piglets (initial body weight 7.14±0.63 kg) weaned at 26±2 days of age were randomly allotted to 5 treatment groups (4 pens per treatment with 18 pigs per pen) for a 28-day trial. Dietary treatments were basal diet without any antimicrobial (negative control; NC), basal diet supplemented with 120 mg/kg feed of neomycin sulfate (positive control; PC) and basal diet supplemented with 2×10(9) (L), 4×10(9) (M) and 20×10(9) (H) CFU/kg feed of B. subtilis KN-42. During the overall period, average daily gain and feed efficiency of piglets were higher in groups PC, M, and H than those in group NC (p<0.05), and all probiotics and antibiotics groups had a lower diarrhea index than group NC (p<0.05). The 16S rDNA gene-based methods were used to analyze faecal bacterial flora on day 28 of experiment. The result of denaturing gradient gel electrophoresis analysis showed that supplementation of B. subtilis KN-42 to the diet changed the bacterial communities, with a higher bacterial diversity and band number in group M than in the other four groups. Real-time polymerase chain reaction analysis showed that the relative number of Lactobacillus were higher in groups PC and H than in group NC (p<0.05), and the supplemented B. subtilis KN-42 to the diet also reduced the relative number of E. coli (p<0.05). These results suggest that dietary addition of B. subtilis KN-42 can improve the growth performance and gastrointestinal health of piglets.

Conversion of yellow wine lees into high-protein yeast culture by solid-state fermentation.

This study is focussed on the possibility of producing a yeast culture with yellow wine lees as a substrate by solid-state fermentation (SSF). Results showed that a yeast count of 1.58 × 109 CFU/g was achieved by signal factor and orthogonal experiments. After fermentation, the starch content in the yeast culture reduced from 32.2% ± 0.5% to 7.5% ± 0.2%, and the contents of crude protein and peptide increased from 36.1% ± 0.8% to 48.0% ± 1.0% and 3.9% ± 0.2% to 7.2% ± 0.4%, respectively. Additionally, large amounts of short peptides and free amino acids were detected by fast protein liquid chromatography (FPLC). These results suggest that yellow wine lees are a suitable substrate for the production of yeast cultures. It can serve as a growth-promoting factor and help reduce the shortage of protein feed in the animal industry. This research provides a potential way for the utilization of agro-industrial residues.

Efficient treatment of old landfill leachate by peroxodisulfate assisted electro-oxidation and electro-coagulation combined system.

Efficient removal of chemical oxygen demand (COD) and ammonium-N (NH4+-N) is the key issue for treatment of old landfill leachate. In this study, a peroxodisulfate assisted electro-oxidation and electro-coagulation coupled system (POCS) adopting Ti/SnO2-Sb2O3/TiO2 and Fe dual-anode was constructed for synergistic removal of COD and NH4+-N in old landfill leachate. Laboratory experiment results showed that with current density of 20 mA cm-2, initial pH value of 8.0 and peroxodisulfate (PDS) concentration of 60 mM, the POCS system can reach removal efficiencies of 84.2% for COD and 39.8% for NH4+-N. The POCS effectively reduced the complexity of macromolecular organics and avoided the need to add acid or base to adjust pH value. The residual NH4+-N could be effectively recovered through struvite precipitation with a 93.8% purity of the precipitate.

Unveiling the microbiota of sauce-flavor Daqu and its relationships with flavors and color during maturation.

This study investigated the microbial community in three-color sauce-flavor Daqu (black, yellow, and white) throughout their maturation processes, together with their physicochemical factors, culturable microbes, flavor components, and fermenting vitalities. Results from high-throughput sequencing revealed distinct microbial diversity, with more pronounced variations in bacterial community than in fungal community. Firmicutes and Ascomycota emerged as the most dominant bacterial and fungal phyla, respectively, during maturation. Genus-level analysis identified Kroppenstedia, Virgibacillus, and Bacillus as dominant bacteria in black Daqu, yellow Daqu, and white Daqu, severally, while Thermoascus was shared as the core dominant fungi for these Daqu. Physicochemical factors, particularly acidity, were found to exert a significant impact on microbial community. Kroppenstedtia was the key bacteria influencing the color formation of these Daqu. Furthermore, correlations between dominant microbes and flavor compounds highlighted their role in Daqu quality. Molds (Aspergillus, Rhizomucor, and Rhizopus), excepting Bacillus, played a crucial role in the formation of pyrazine compounds. Consequently, this study offers innovative insights into the microbial perspectives on color and pyrazine formation, establishing a groundwork for future mechanized Daqu production and quality control of sauce-flavor baijiu.

Effect of epimedium polysaccharide-propolis flavone immunopotentiator on immunosuppression induced by cyclophosphamide in chickens.

Two hundred and fifty 11-day-old chickens were randomly assigned into 5 groups and except normal control group injected with cyclophosphamide once a day for 3 successive days. At day-14-old, all chickens were vaccinated with Newcastle disease vaccine. At the same time of the first vaccination, the chickens in three experimental groups were injected respectively with epimedium polysaccharide-propolis flavone immunopotentiator (EPI) at three dosages, once a day for 3 successive days. On days 7, 14, 21 and 28 after the first vaccination, the serum antibody titer and IgG, IgM, IFN-γ and IL-6 concentrations, peripheral lymphocyte proliferation, including immune organ index on day 28, were measured. The results demonstrated that EPI at high and medium doses could significantly enhance antibody titer and IgG, IgM, IFN-γ and IL-6 concentrations, promote lymphocyte proliferation and enlarge immune organ index as compared with model control group. This indicated that EPI could effectively resist the immunosuppression.

Mitsuaria chitosanase with unrevealed important amino acid residues: characterization and enhanced production in Pichia pastoris.

A chitosan plate assay was employed to screen for chitosanase-producing bacterial strains and isolate 141 was found to exhibit high activity. Characterization of this isolate revealed that it belonged to Mitsuaria (designated as Mitsuaria sp. 141). The encoded chitosanase (choA) gene was then cloned by PCR and the deduced amino acid sequence showed 98% identity to a formerly described Mitsuaria chitosanitabida 3001 ChoA (McChoA). Surprisingly, the ChoA encoded by Mitsuaria sp. 141 (MsChoA) appeared to have a much higher optimum temperature compared to McChoA. Site-directed mutagenesis was then employed to generate five MschoA mutant genes encoding MsChoA K204Q, R216K, T222N, R216K/T222N, or K204Q/R216K/T222N. All the ChoA mutants exhibited a much lower specific activity and a lower optimum temperature. The results confirmed that the substitution of three non-conserved amino acids accounts for the major reduction of the enzyme activity in MsChoA. Furthermore, the MschoA gene was cloned for over-expression in Pichia pastoris after coding sequence optimization. One of the P. pastoris transformants with Mut(S) phenotype was found to produce 1,480.2 ± 340.9 U ChoA mL(-1) of cell culture by high-cell-density fermentation. This represents the highest yield of recombinant ChoA production that has ever been reported thus far. The recombinant P. pastoris strain should therefore be well suited for industrial-scale production of chitosanase.