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Background This study examined how rhizosphere fungi influence the accumulation of chemical components in fruits of a small population species of Cinnamomum migao. Results Ascomycota and Basidiomycota were dominant in the rhizosphere fungal community of C. migao. Pestalotiopsis and Gibellulopsis were associated with α-Terpineol and sabinene content, and Gibellulopsis was associated with crude fat and carbohydrate content. There were significant differences in rhizosphere fungal populations between watersheds, and there was no obvious change between fruiting periods. Gibberella, Ilyonectria, Micropsalliota, and Geminibasidium promoted sabinene accumulation, and Clitocybula promoted α-Terpineol accumulation. Conclusion The climate-related differentiation of rhizosphere fungal communities in watershed areas is the main driver of the chemical composition of C. migao fruit. The control of the production of biologically active compounds by the rhizosphere fungal community provides new opportunities to increase the industrial and medicinal value of the fruit of C. migao.

Laportea bulbifera, named Hong He Ma in Chinese, is a Chinese herbal medicine commonly used by the Miao nationality of China. In this study, 43 batches of L. bulbifera were collected from different origins in China. Ethanol, ethyl acetate and petroleum ether were used to prepare different extracts of the plant. UHPLC technique was used to establish the fingerprints, whereas DPPH assay and RAW264.7 inflammatory cell models were used to evaluate the antioxidant and anti-inflammatory activities, respectively. Moreover, the spectrum-effect relationship between relative peak area of common peaks and efficacy value was set up by multivariate statistical analysis. Furthermore, 10 batches were selected randomly for validation of those models. The results showed that ethyl acetate and petroleum ether extracts possess excellent antioxidant and anti-inflammatory activities, respectively. Peaks A6 and A7 demonstrated the greatest antioxidant activity, while peak A17 showed the strongest anti-inflammatory activity. After a verified experiment, the result was obtained and illustrated that the spectrum-effect relationship which we established could reliably infer antioxidant and anti-inflammatory compounds of the Chinese herbal medicine.

A new flavonol glycoside named Sabiapside A (1), along with four known compounds, quercetin-3-O-gentiobioside (2), camellianoside (3), isobariclisin-3-O- rutinoside (4), tsubakioside A (5), was isolated from Sabia parviflora. Their structures were elucidated by extensive spectroscopic analysis including MS, UV, IR and NMR data. The antioxidant activities of these glycosides evaluated by ABTS+ and DPPH radical scavenging reaction was higher than that of vitamin C used as the reference antioxidant.

Nowadays, the increased prevalence of sub-health significantly affects human health worldwide. Suppressed sub-healthy by dietotherapy/herbal remedy which showed excellent safety profile, low cost and effectiveness, is an effective way. In this research, the fingerprint and antioxidant activity of Sabia parviflora were obtained by HPLC instrument and DPPH, ABTS, FRAP heatmap assays. And the antioxidant active substances were selected by spectrum-effect relationship. The results showed that significant differences in chemical compositions of samples from different sources, and EW, EE extracts had strong antioxidant activity. The antioxidant activity of Sabia parviflora was mainly determined by the complex interaction of various flavonoids (promoting, competing or antagonizing). These findings revealed that the abundant flavonoids in Sabia parviflora had significant antioxidant activity and could be potential antioxidants. With therapeutic potential for sub-health, this special tea might provide dietotherapy/herbal to remedy sub-healthy population.

Lysozymes are known as ubiquitously distributed immune effectors with hydrolytic activity against peptidoglycan, the major bacterial cell wall polymer, to trigger cell lysis. In the present study, the full-length cDNA sequence of a novel sea urchin Strongylocentrotus purpuratus invertebrate-type lysozyme (sp-iLys) was synthesized according to the codon usage bias of Pichia pastoris and was cloned into a constitutive expression plasmid pPIC9K. The resulting plasmid, pPIC9K-sp-iLys, was integrated into the genome of P. pastoris strain GS115. The bioactive recombinant sp-iLys was successfully secreted into the culture broth by positive transformants. The highest lytic activity of 960 U/mL of culture supernatant was reached in fed-batch fermentation. Using chitin affinity chromatography and gel-filtration chromatography, recombinant sp-iLys was produced with a yield of 94.5 mg/L and purity of > 99%. Recombinant sp-iLys reached its peak lytic activity of 8560 U/mg at pH 6.0 and 30 °C and showed antimicrobial activities against Gram-negative bacteria (Vibrio vulnificus, Vibrio parahemolyticus, and Aeromonas hydrophila) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis). In addition, recombinant sp-iLys displayed isopeptidase activity which reached the peak at pH 7.5 and 37 °C with the presence of 0.05 M Na+. In conclusion, this report describes the heterologous expression of recombinant sp-iLys in P. pastoris on a preparative-scale, which possesses lytic activity and isopeptidase activity. This suggests that sp-iLys might play an important role in the innate immunity of S. purpuratus.

Infectious diseases caused by antibiotic multidrug-resistant microorganisms are major causes of morbidity and mortality in humans. Hence, there is an urgent need to search for new antimicrobial agents. Initially known as a defensive effector in the innate immunity of certain organs of the human body, human goose-type lysozyme 2 (hLysG2) has been shown to possess therapeutically useful potential against multidrug-resistant microorganisms. Developing a novel strategy for large-scale production that provides high yields of this protein with high purity, quality, and potency is critical for pharmaceutical applications. To overcome the issues related to prokaryotic expression, here we report the production of recombinant hLysG2 (rhLysG2) using the methylotrophic yeast Pichia pastoris as expression host. The strong inducible alcoholoxidase 1 (AOX1) promoter was used to drive expression of the optimized hLysG2 gene. Under the optimal expression conditions, the lytic activity of rhLysG2 reached 113 U/mL of culture supernatant in shake flask cultivation and this was increased to 2084 U/mL in fed-batch fermentation. Using chitin affinity chromatography and size-exclusion chromatography, rhLysG2 was produced with a yield of 137 mg/L, purity of > 99%, molecular weight of 21,504.6 Da, and specific activity of 13,500 U/mg. In vitro assays indicated that rhLysG2 possessed muramidase activity, isopeptidase activity, and free radical scavenging activity. This report describes an efficient strategy for the production of biologically active rhLysG2 in P. pastoris on a large scale with a high yield, which provides a solid foundation for possible future pharmaceutical applications.

Vertically aligned TiO2 nanotube arrays (~8 μm long, ~110 nm wide) have been fabricated through anodic oxidation of Ti-metal sheet in fluoride-containing electrolyte. By changing the volume ratio of ethylene glycol and diethylene glycol in the electrolyte, TiO2 nanotube arrays with different tube-to-tube lateral spacing, i.e., closely packed, just separated, and fully separated, have been synthesized and applied as photoanodes for dye-sensitized solar cells (DSSCs). Photovoltaic efficiency of 2.99 %, 3.34 %, and 3.44 % has been obtained for DSSCs based on the closely packed, just separated, and fully separated TiO2 nanotube arrays, respectively, illustrating the effect of tube-to-tube lateral spacing of TiO2 nanotube arrays on the performances of DSSCs. It is suggested that fully separated TiO2 nanotube arrays are beneficial to the conversion efficiency of DSSCs due to higher dye loading and faster electron transfer.

Nano-husk ashes were prepared by burning rice-husk with self-propagating method. The super-hydrophobic SiO 2 films from nano-husk ash were prepared by sol–gel method using hydroxy silicone oil (HSO), hexamethyldisilazane (HMS), or methyl triethoxysilane (MTS) as modifiers. The effects of modifiers on the hydrophobic property of SiO 2 films were studied, and the performances were characterized by the XRD, UV–vis, BET, EDS, SEM, IR, and Contact Angle Analyzer. The results showed that the contact angle of SiO 2 films was more than 160° when volume ratio of the modifiers to silicon-sodium solution (SSS) was 0.15. The mechanism of modifiers on SiO 2 surfaces is a graft copolymerization. The hydrophobic groups in the modifiers replace the hydroxy groups on SiO 2 surfaces and make SiO 2 surfaces present super-hydrophobicity.

Nano-rice husk ashes were prepared by burning rice husk with a self-propagating method. The white carbon black with high purity was prepared by an alkali dissolving–acid reaction method from nano-husk ash. The super-hydrophobic SiO2 films were prepared by the sol–gel method using hexamethyldisilazane as a modifier. The effects of the pH and reaction time in the acid reaction process on the purity of the white carbon black, and the effect of the modifier on the hydrophobic property of SiO2 films were studied. The performances were characterized by XRD, BET, SEM, IR, and contact angle analyzer. The results showed that the purity of white carbon black reached 98.48 % when the NaOH solution with the rice husk ash was heated for 2 h at 90 °C, then the pH of the solution was adjusted by sulfuric acid to 3, and the acid reaction time was 2 h. The contact angle of SiO2 films was more than 160° when volume ratio of the modifier to silica–sodium hydroxide mixed solution was 0.15. The mechanism of the modifier on SiO2 surfaces is a graft copolymerization. The hydrophobic groups in the modifier replace the hydroxy groups on SiO2 surfaces and make SiO2 surfaces present super-hydrophobicity.

Composite catalyst honeycombs without sintering were prepared via kneading, mulling, extrusion molding, and solidifying at room temperature with the magnesite oxychloride gels modified by nano-rice husk ash (RHA) as a solidifying agent. The effects of nano-RHA and composite water-resistant agents on the water resistance of magnesite materials were studied. The solidification of the modified magnesite gels on TiO2 catalyst honeycombs was analyzed. The experiments show that the proportional addition of nano-RHA markedly increases the water resistance of magnesite materials without reducing the bending strength, and the softening coefficient increases from 0.29 to 0.78. With further addiition of the complex water-resistant agents, the softening coefficient increases from 0.78 to 0.97. The optimal mass ratio of MgO in the solidifying agent to TiO2 is 4:1, and the bending strength of unsintered catalyst honeycombs is 11.46 MPa. The desulfurization rate and denitration rate of this composite catalyst honeycomb on simulation smoke was 97 and 65 %, respectively, in 3 h.

Two β-glucosidase/xylosidase genes, Rubg3A and Rubg3B, were cloned from yak rumen uncultured microorganisms by metagenome method and function-based screening. Recombinant RuBG3A and RuBG3B purified from Escherichia coli were characterized for enzymatic properties, and they exhibited activity against 4-nitrophenyl-β-D: -glucopyranoside and 4-nitrophenyl-β-D: -xylopyranoside, suggesting bifunctional β-glucosidase/xylosidase activity. Chromatography analysis showed that they could effectively hydrolyze cellooligosaccharide substrates, indicating the facilitation in saccharification of cellulose. RuBG3A and RuBG3B can also increase the reducing sugar released in xylan hydrolysis to 218% and 169%, respectively, through synergism with xylanase, suggesting their application in hemicellulose saccharification. Molecular modeling and substrate docking showed that there should be one active center responsible for the bifunctional activity in each enzyme, since the active site pocket is substantially wide to allow the entry of both β-glucosidic or β-xylosidic substrates, which elucidated the structure-function relationship in substrate specificities. Therefore, the enzymatic properties, the participation in hydrolysis of cellooligosaccharides, and the synergism with xylanase make RuBG3A and RuBG3B very interesting candidates for saccharification of both cellulose and hemicellulose.

T cells are major lymphocytes in the blood and passengers across the tumor vasculature. If these T cells are retained in the tumor site, a therapeutic potential will be gained by turning them into tumor-reactive cytotoxic T lymphocytes (CTLs). A fusion protein composed of human vascular endothelial growth factor (VEGF) and staphylococcal enterotoxin A (SEA) with a D227A mutation strongly repressed the growth of murine solid sarcoma 180 (S180) tumors (control versus VEGF-SEA treated with 15μg, mean tumor weight: 1.128g versus 0.252g, difference=0.876g). CD4(+) and CD8(+) T cells driven by VEGF-SEA were accumulated around VEGFR expressing tumor cells and the induced CTLs could release the tumoricidal cytokines, such as interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Meanwhile, intratumoral CTLs secreted cytolytic pore-forming perforin and granzyme B proteins around tumor cells, leading to the death of tumor cells. The labeled fusion proteins were gradually targeted to the tumor site in an imaging mice model. These results show that VEGF-SEA can serve as a tumor targeting agent and sequester active infiltrating CTLs into the tumor site to kill tumor cells, and could therefore be a potential therapeutical drug for a variety of cancers.