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Additional file 1: Table S1. The primers used in qPCR of the lncRNA and mRNAs.

In this work a headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O) was developed to evaluate the profile of the volatile compounds that contribute to the aroma of Antrodia camphorata in submerged culture. For this purpose, the HS-SPME sampling method for the volatile compounds of A. camphorata in submerged culture was optimised by a D-optimal design. A HS extraction of the culture broth of A. camphorata followed by incubation on a carboxen/polydimethylsiloxane (CAR/PDMS) fibre during 31.8min at 54.6°C gave the most effective and accurate extraction of the volatile compounds. By the optimised method, a total of 49 volatile compounds were identified in culture broth of A. camphorata, while a total of 55 volatile compounds were identified in the mycelia. A series of C(8) aliphatic compounds (mushroom-like odour), several lactones (fruity odour) and l-linalool (citrus-like odour) were the most potent key odourant in both the mycelia and culture broth. This combined technique is fast, simple, sensitive, inexpensive and useful to monitor volatile compounds associated to A. camphorata.

The metabolites produced by Stigmatella WXNXJ-B inhibited the growth of tumor cells. The aims of this research were to evaluate the inhibition potency to different tumor cell lines and to study the effects of ammonium, phosphate and iron salts on bacterial growth and production of bioactive metabolites in Stigmatella WXNXJ-B fermentation. The results showed that the chloroform extract (CE-ME) showed the strongest growth inhibition bioactivity on mouse melanoma cell line (B16), murine colon carcinoma cell line (CT-26), human liver carcinoma cell line (HepG2) and human breast cancer cell line (MDA-MB231) in vitro and the IC50 values were 9.94, 7.33, 11.34 and 11.66 μg ml−1 respectively. The IC50 value was above 700 μg ml−1 on normal mouse spleen cells. Morphology happened changes in B16 cells treated with CE-ME. The anti-tumor metabolites were mainly produced during the stationary phase of the bacterial growth. Cell growth was stimulated at the phosphate concentration below 5 mM, but it was inhibited partly with 10 mM phosphate. The production of bioactive substances was inhibited by the phosphate. Ammonium increased the cell growth by 250% at 5 mM addition. The inhibition rate to B16 cells was increased to 89% at the concentration of 40 mM ammonium. The bacteria showed the best growth with 4 mM iron. Iron had little effect on the production at 2 mM, but bigger inhibition effect at higher iron concentration.

Fusarium mairei , a paclitaxel-producing fungal endophyte, its effects on taxoid synthesis in Taxus cells were investigated via adding the fungal endophyte culture supernatants (FECS) to the suspension cultures of Taxus cuspidata . The concentration of FECS was determined on its total carbohydrate. When 100 mL of Taxus cell suspension cultures were treated with several dosages of FECS (4, 6 and 8 g) at day10, the cultures treated with 6 g FECS produced the highest yield of paclitaxel (5.84 mg L −1 ), which was 1.8-fold the yield from controls (3.14 mg L −1 ). The major elicitor element in FECS was an oligosaccharide of 2 kDa. In addition, the cultures treated with 6 g FECS resulted in 25.86 mg L −1 of the precursor 10-deacetylbaccatin III (10-DAB) accumulation, which was 11 times that of control cultures (2.32 mg L −1 ), and 4.7 times higher than that of cultures treated with 200 μM methyl jasmonate (MJ) (5.43 mg L −1 ). These results indicate that FECS favors to stimulate 10-DAB accumulation more effectively than paclitaxel accumulation.

The co-culture of the suspension cells of Taxus chinensis var. mairei and its endophytic fungi, Fusarium mairei, in a 20-L co-bioreactor was successfully established for paclitaxel production. The co-bioreactor consists of two-unit tanks (10 L each) with a repairable separate membrane in the center, culturing Taxus suspension cells in one tank and growing fungi in another. By optimizing the co-culture conditions, there was a desirable yield of paclitaxel in Taxus cell cultures. The Taxus cell cultures by co-culture produced 25.63 mg/L of paclitaxel within 15 days; it was equivalent to a productivity of 1.71 mg/L per day and 38-fold higher than that by uncoupled culture (0.68 mg/L within 15 days). The optimum conditions for co-culture in the co-bioreactor were: B5 medium, inoculating fungi when Taxus cells had grown for 5 days in the co-bioreactor, hydrophilic separate membrane in the center of the co-bioreactor, and air flow rate of 1:0.85 v/v/m in fungus cultures.

Effects of a fungal endophyte, Fusarium mairei, on growth and paclitaxel formation of Taxus cuspidata cells were investigated by adding fungal endophyte culture supernatant (FECS) to suspension cultures of T. cuspidata cells. The main effective chemical responsible for paclitaxel formation in FECS was an exopolysaccharide (EPS) of molecular weight ~2 kDa. FECS fractions except EPS stimulated growth of Taxus cells but had no effects on paclitaxel accumulation. Additionally, elicitation efficiency of FECS based on different culture conditions was studied. EPS content in FECS was related to FECS culture conditions. FECS with long cultivation and high-aeration cultivation contained higher EPS content and resulted in higher paclitaxel yield than that with short cultivation and low-aeration cultivation. The maximum yield of paclitaxel from Taxus cultures, elicited by FECS with 9-day cultivation, was 4.7-fold that of the control cultures.

Endophytic fungi (Fusarium mairei) culture broth (EFCB) was added to cell suspension cultures of Taxus cuspidata. After 5 days, cultures of T. cuspidata given 4 ml of EFCB produced a maximal yield of 6.11 mg/l paclitaxel, with a release ratio of 75%, 2- and 6.8-fold, respectively, greater than the controls. The active element in EFCB is an exopolysaccharide of approximately 79 kD. Endophytic fungi produced 0.19 mg/l of paclitaxel in its producing medium. However, when the supernatant of Taxus cell suspension cultures from day 20 was added to the paclitaxel-producing medium, the biomass of fungi decreased by 24% and the yield of paclitaxel by 45%. In a co-culture system of plant and fungus, the yield of paclitaxel (12.8 mg/l) was >2-fold higher than that in the EFCB-treatment system.

The Lactobacillus fermentum R1 and Lactobacillus delbrueckii subsp. delbrueckii R2 were two dominant lactic acid bacteria strains in mixed starters, intensively used to manufacture fermented rice noodle in Hunan province of China. In this paper, the FT-IR and RVA pasting properties of fermented rice flour were investigated with each of dominant strains as single starter. The ester carbonyl group band at 1742 cm−1 and IR absorbance band at 1047 cm−1 disappeared in the FT-IR spectra of fermented rice flour. The FT-IR absorbance band at 1046.86 cm−1 was detected only in non-fermented rice flour. Both breakdown and setback RVA parameters of fermented rice flours reduced. The results suggested that the effects of lactic acid fermentation of two dominant strains on the FT-IR and RVA pasting properties of rice flour were same and the crystal structures in starch granules were moderately damaged during fermentation process.

The biological function of GFPPS1b, a novel polysaccharide-peptide isolated from cultured mycelia of Grifola frondosa GF9801, was well investigated. GFPS1b has anti-tumor activity and can significantly inhibit the proliferation of SGC-7901 cells, whereas slightly influences the growth of human normal liver cell line L-02. When treated with GFPS1b, SGC-7901 cells showed typical apoptotic morphological features such as the loss of villus and appearance of apoptotic bodies on the cell surface, volume reduction, and chromatin condensation, by scanning electron microscopy (SEM) and fluorescent microscopy (Hoechst 33342). The results of flow cytometry analysis and annexin V-PI assay showed that the SGC-7901 cell cycle was arrested in the G(2)/M phase, the subdiploid peak of DNA characteristic of apoptotic was also observed, and the apoptosis ratio was about 15.08%. DNA isolated from SGC-7901 cells cultured with GFPS1b showed a typical DNA 'ladders' of apoptosis in agarose gel electrophoresis. Further investigation results showed that the apoptotic machinery of SGC-7901 induced by GFPS1b was associated with drop in mitochondrial trans-membrane potential, upregulation of Bax, downregulation of Bcl-2, and activation of caspase-3. Our finding suggests that GFPS1b could suppress SGC-7901 cell growth and reduce cell survival via arresting cell cycle and inducing apoptosis of tumor cells.

The strain Aspergillus fumigatus XC6 isolated from mildewing rice straw was evaluated for its ability to decolorize a dye industry effluent. The strain was capable of decolorizing dyes effluent over a pH range 3.0-8.0 with the dyes as sole carbon and nitrogen sources. The optimum pH was 3.0; however, supplemented with either appropriate nitrogen sources (0.2% NH(4)Cl or (NH(4))(2)SO(4) ) or carbon sources (1.0% sucrose or potato starch), the strain decolorized the effluent completely at the original pH of the dyes effluent. Therefore, A. fumigatus XC6 is an efficient strain for the decolorization of reactive textile dyes effluents, and it might be a practical alternative in dyeing wastewater treatment.

A 21-kDa heteropolysaccharide, coded as GFPS1b, was obtained from the cultured mycelia of Grifola frondosa GF9801 by hot-water extraction, ethanol precipitation, and fractioned by DEAE Sepharose Fast-flow, followed by the purification with Sephadex G-100 column chromatography using an AKTA purifier. It exhibited more potent anti-proliferative activity on MCF-7 cells than other polysaccharide fractions. GFPS1b was an acidic polysaccharide with approximately 16.60% protein and 4.3% uronic acid. Gas chromatography of absolute acid hydrolysate of GFPS1b suggested that it was composed of D-glucose, D-galactose, and L-arabinose with a molar ratio of 4:2:1. Periodate oxidation, Smith degradation, partial acid hydrolyzation, methylation analysis, FT-IR, and (1)H, (13)C NMR spectroscopy analysis revealed that GFPS1b had a backbone consisting of alpha-(1-->4)-linked D-galacopyranosyl and alpha-(1-->3)-linked D-glucopyranosyl residues substituted at O-6 with glycosyl residues composed of alpha-L-arabinose-(1-->4)-alpha-D-glucose (1--> linked residues.

In this work, a three-level Box–Behnken factorial design was employed combining with response surface methodology (RSM) to optimize the medium composition for the production of the mycelial biomass and exo-polymer in submerged cultures by Grifola frondosa GF9801. A mathematical model was then developed to show the effect of each medium composition and their interactions on the production of mycelial biomass and exo-polymer. The model estimated that, a maximal yield of mycelial biomass (17.61 g/l) could be obtained when the concentrations of glucose, KH2PO4, peptone were set at 45.2 g/l, 2.97 g/l, 6.58 g/l, respectively; while a maximal exo-polymer yield (1.326 g/l) could be achieved when setting concentrations of glucose, KH2PO4, peptone at 58.6 g/l, 4.06 g/l and 3.79 g/l, respectively. These predicted values were also verified by validation experiments. Compared with the values obtained by other runs in the experimental design, the optimized medium resulted in a significant increase in the yields of mycelial biomass and exo-polymer. Maximum mycelial biomass yield of 22.50 g/l was achieved in a 15-l fermenter using the optimized medium.

Effects of cerium (Ce3+) on membranous protective enzymes in rape seedlings exposed to two levels of enhanced ultraviolet-B radiation (UV-B, 280 ∼ 320 nm) were studied by hydroponics in the laboratory. The results show that the chlorophyll content decreases and membrane permeability increases in the leaves under UV-B irradiation with an intensity of 0.15 and 0.35 W·m−2. The activities of SOD, CAT and POD are first increased and then decreased in leaves exposed to a low level of UV-B radiation. POD activity in leaves exposed to a high level of UV-B radiation is enhanced constantly. The sensitivities of these enzymes to UV-B radiation are SOD > CAT > POD. The injury by UV-B radiation on the functions of protective enzymes is lightened, their ability to scavenge radicals is improved, and the membrane permeability is maintained by Ce. Furthermore, the protective effect of cerium is more obvious in plants exposed to low levels of UV-B radiation than to high levels of it. Accordingly, all results prove that the protective effect of Ce on plants under UV-B radiation is realized through the protective system of plants.

An alkali-tolerant cellulase-free xylanase producer, WLI-11, was screened from soil samples collected from a pulp and paper mill in China. It was subsequently identified as a Pseudomonas sp. A mutant, WLUN024, was selected by consecutive mutagenesis by u.v. irradiation and NTG treatment using Pseudomonas sp. WLI-11 as parent strain. Pseudomonas sp. WLUN024 produced xylanase when grown on xylosidic materials, such as hemicellulose, xylan, xylose, and wheat bran. Effects of various nutritional factors on xylanase production by Pseudomonas sp. WLUN024 with wheat bran as the main substrate were investigated. A batch culture of Pseudomonas sp. WLUN024 was conducted under suitable fermentation conditions, where the maximum activity of xylanase reached 1245 U ml−1 after incubating at 37 °C for 24 h. Xylanase produced by Pseudomonas sp. WLUN024 was purified and the molecular weight was estimated as 25.4 kDa. Primary studies on the characteristics of the purified xylanase revealed that this xylanase was alkali-tolerant (optimum pH 7.2–8.0) and cellulase-free. In addition, the xylanase was also capable of producing high quality xylo-oligosaccharides, which indicated its application potential in not only pulp bio-bleaching processes but also in the nutraceutical industry.

Contamination by Bacillus cereus occasionally develops in Chinese fermented rice noodle products. To determine whether the growth of the pathogen might be inhibited by natural mixed lactic acid bacteria (LAB) starters in rice fermentation, B. cereus YSP-A3-2 was artificially added together with LAB starters by inoculation just before the fermentation process. The decrease of pH from 6.8 to 4.0 took place during the first 8 h and pH stayed under 4.0 during the rest of fermentation process in both of the concentrations of B. cereus (103 cfu/ml and 104 cfu/ml) tested, which decreased to 102 cfu/ml and 103 cfu/ml final concentration, respectively. The results suggest that the occasional contamination by B. cereus could be inhibited by the natural LAB starter, which was used in Chinese rice noodle factory by the back-slopping way.

To further understand the hepatoprotective activity of Antrodia camphorata in living systems and the possible mechanisms of this protection, the effects of fractions from A. camphorata in submerged culture on the liver and its antioxidative system in acute ethanol intoxicated rats were investigated. The results showed that the ethanolic extract (Fr-I) of A. camphorata was the most effective in the prevention of ethanol-induced acute liver injury and free radical generation in rats. The ethanolic extract administrated prior to ethanol significantly prevented the increase in serum levels of hepatic enzyme markers such as aspartate aminotransferase and alanine aminotransferase. It also normalised the increase of hepatic malondialdehyde concentration and the decrease of glutathione levels in the liver. Moreover, Fr-I improved the ethanol-induced decrease of hepatic glutathione peroxidase and reductase activities. On the basis of these results, the ethanolic extract of A. camphorata may exert its hepatoprotective activity by up-regulating GSH-dependent enzymes and inhibiting free radical formation in the liver.

Effect of cerium (Ce3+) on the growth, photosynthesis and antioxidant enzyme system in rape seedlings (Brassica juncea L.) exposed to two levels of UV-B radiation (T1: 0.15 W/m2 and T2: 0.35 W/m2) was studied by hydroponics under laboratory conditions. After 5 d of UV-B treatment, the aboveground growth indices were obviously decreased by 13.2%-44.1% (T1) and 21.4%-49.3% (T2), compared to CK, and except active absorption area of roots, the belowground indices by 14.1%-35.6% (T1) and 20.3%-42.6% (T2). For Ce+UV-B treatments, the aboveground and belowground growth indices were decreased respectively by 4.1%-23.6%, 5.2% -23.3% (Ce+T1) and 10.8%-28.4%, 7.0%-27.8% (Ce+T2), lower than those of UV-B treatments. The decrease of growth indices appeared to be the result of changes of physiological processes. Two levels of UV-B radiation induced the decrease in chlorophyll content, net photosynthesis rate, transpiration rate, stomatal conductance and water use efficiency by 11.2%-25.9% (T1) and 20.9%-56.9% (T2), whereas increase in membrane permeability and activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) by 6.9%, 22.8%, 21.5%, 9.5% (T1) and 36.6%, 122.3%, 103.5%, 208.9% (T2), respectively. The reduction of the photosynthetic parameters in Ce+UV-B treatments was lessened to 3.2%-13.8% (Ce+T1) and 4.9%-27.6% (Ce+T2), and the increase of membrane permeability and activities of antioxidant enzymes except POD in the same treatments were lessened to 2.4%, 8.4%, 6.6% (Ce+T1) and 30.1%, 116.7%, 75.4% (Ce+T2). These results indicate that the regulative effect of Ce on photosynthesis and antioxidant enzymatic function is the ecophysiological basis of alleviating the suppression of UV-B radiation on growth of seedlings. Furthermore, the protective effect of Ce on seedlings exposed to T1 level of UV-B radiation is superior to T2 level.

Ozonation was applied to investigate the removal efficiency of 6 odorous organic compounds in eutrophic water from Taihu Lake (Wuxi). The results showed that the ozonation process could be described by first order kinetic model and the overall kinetic rates of the odorous compounds were determined by their chemical characteristic and structure, which could be ranked: beta-Ionone (3.3 x 10(-3) s(-1))beta-Cyclocitral (2.8 x 10(-3) s(-1))2,4-Decadienal (2.7 x 10(-3) s(-1))Neryl Acetone (2.2 x 10(-3) s(-1))Geosmin (1.4 x 10(-3) s(-1))2-Methylisoborneol (5.6 x 10(-4) s(-1)). Ozonation of eutrophic water led to the formation of a series of aldehydes, ketones, alcohols and esters. The influence of bicarbonate and natural organic carbon on odorous compounds ozonation were further investigated, results showed that the bicarbonate could restrain the effect of ozonation by cutting down the radical pathway and natural organic carbon in the water by competition with target compounds.

A novel macrolide with dioxa and double ring pentadecanone, named as phoxalone, isolated from the culture broth of a myxobacterium Sorangium cellulosum WXNXJ-C, was well investigated. The chemical structure of Phoxalone was elucidated by spectroscopic analysis including UV, IR, (1)H NMR, MALDI-TOF-MS, and LC/MS spectra. The results of cytotoxic bioactivities on human non-small lung cancer H446, in vitro, showed that not only did phoxalone express higher antitumor bioactivity than many antitumor drugs, but it also displayed less cytotoxicity to normal human liver L02 cell lines (IC(50), 286 microg mL(-1)). Further cytotoxic bioactivity study indicated that phoxalone could induce H446 cell line apoptosis in vitro. More investigation results of flow-cytometric analysis suggested that phoxalone arrested the mitosis of H446 cell line at G2/M phase. Hence, phoxalone and its derivatives or analogs would reveal huge research value and fascinating foreground.

A novel macrolide, isolated from the myxobacteria Sorangium cellulosum WXNXJ-C, was identified as 1,7,12,13-tetrahydroxy-14-methoxy-8,10-dimethyl-6-phenyl-5,15-dioxa-bicyclo[9.3.1]pentadecan-4-one, "Phoxalone". It had minimum IC(50) values of 0.24, 6.9, 10.3, 0.98 and 4 microg/ml, respectively, against tumour cell lines: B16, Bel7402, H446, MCF-7, and SGC7901. In addition, it had less cytotoxicity to normal human liver L02 cell lines (286 microg/ml, 24 h). A cytotoxic bioactivity study on H446 cell line in vitro suggested that Phoxalone arrested the mitosis in the G2/M phase.

To study the growth inhibition of Weikangfu recipe on S180 tumor and its apoptotic induction.S180-bearing mice were orally administrated with different dosages of Weikangfu recipe, and the growth inhibition was evaluated; apoptotic cells induced were detected by flow cytometry and DNA agarose gel electrophoresis.Weikangfu recipe showed significant inhibition on the growth of S180 tumor in a dose-dependent manner, compared with the control group. From apoptotic analyses, Weikangfu recipe induced a dose-dependent apoptosis of S180 tumor cells and arrested the cell cycle distribution at G0-G1 phase. At the same time, the up-regulation of p53 and bax and down-regulation of bcl-2 were observed in S180 tumor cells of the treated groups.Our findings demonstrate that Weikangfu recipe can significantly inhibit the growth of S180 tumor and induce apoptosis through expression alteration of p53, bax and bcl-2.

To supply the scientific basis of research and development of the medicinal value of Polygonum cuspidatum.One composition was isolated from the roots of Polygonum cuspidatum by cytotoxicity based fractionation and identified by HPLC-MS, UV scanning and IR. The inhibition and morphology of L-02, Hep G2, SHZ-888, MCF-7, MCF-7/ADM cells growth caused by this composition was determined by MTT assay and HE dyeing.This composition was identified as trans-and cis-resveratrol. It could specifically inhibit proliferation of many cancer cells but not human normal liver cell. We investigated the cytotoxicity of resveratrol to adriamycin-resistant MCF-7 cell in virtro.Resveratrol is a new anticancer composition which is less toxicity and higher efficiency in Polygonum cuspidatum.

Resveratrol, a plant polyphenol, is found in significant amounts in the skin of grapes and in some traditional herbs. It is reported to exert different biological activities, such as inhibiting lipid peroxidation, scavenging free radicals, inhibiting platelet aggregation, and anticancer activity. In order to screen the resveratrol-binding proteins, we synthesized biotinylated resveratrol, purified by liquid chromatography and immobilized it into streptavidin-coated microplate wells. 3-(4,5-Demethylthiazol-)-2,5-diphenyl tetrazolium bromide assay showed little change in the anticancer activity of biotinylated resveratrol in vitro. A random library of phage-displayed peptides was screened for binding to immobilized resveratrol to isolate resveratrol-binding proteins. Several peptides were found to bind to resveratrol specifically, which was proven by enzyme-linked immunosorbent assay. Through amino acid sequence analysis of the selected peptides and human proteins using the BLAST program, the results showed that resveratrol has an affinity for various proteins such as breast cancer-associated antigen, breast cancer resistance protein, death-associated transcription factor, and human cyclin-dependent kinase. These results demonstrate that our study provides a feasible method for the study of binding proteins of natural compounds using a phage-displayed random peptide library.

Effects of the simulated acid rain (AR) and ultraviolet-B (UV-B, 280-320 nm) radiation with a single or two ways simultaneously (AR + UV-B) on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress (AR or UV-B) is stronger than that to dual stresses (AR + UV-B). Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation. According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability, MDA content and photosynthetic characteristics to the above-mentioned stresses was as follows: AR + UV-BUV-BAR.

The hepatoprotective effects of the mycelia of Antrodia camphorata and Armillariella tabescens were evaluated in vivo using acute ethanol-intoxicated rats as an experimental model. Animals were orally treated with Antrodia camphorata (0.5 or 1.0 g/kg b.w.) or Armillariella tabescens (0.5 or 1.0 g/kg b.w.) for 10 days whereas controls received vehicle only. At the end of the experimental 10-day period, the animals were administered by gavage with an acute ethanol dose of 5.0 g/kg b.w. diluted in deionized water (6:4, v/v) and sacrificed at 18 h after ethanol administration. The degree of protection was measured by using biochemical parameters like serum transaminases (AST and ALT), alkaline phosphatase (ALP), bilirubin. Meanwhile, the histopathological studies were carried out to support the above parameters. Administration of Antrodia camphorata or Armillariella tabescens markedly prevented ethanol-induced elevation of levels of serum AST, ALT, ALP, and bilirubin comparable with standard drug silymarin.

Microbial xylanases have received a great deal of attention in the last two decades for their potential applications in food, paper making and animal feed industries. Bacillus pumilus WL-11 was identified as a producer of alkane xylanase free of cellulase after screening soil samples of paper-making factories. The xylanase A (XylA) was purified to homogeneity from the culture filtrate of Bacillus pumilus WL-11 by (NH4) 2SO4 precipitation, CM-Sephadex and Sephadex G-75 chromatographies. The molecular mass of XylA is estimated to be 26.0 kD by SDS-PAGE and its isoelectric point is 9.5. The apparent Km is 16.6 mg/mL and V(max) is 1263 micromol/(min x mg) towards oat spelt xylan. XylA is optimally active between pH 7.2 and 8.0, and stable at pH 6.0 to 10.4. The enzyme is optimally active at 45 degrees C - 55 degrees C and stable at temperature below 45 degrees C, with its half time of activity of 35 min and 15 min at 55 degrees C and 60 degrees C respectively. HPLC analysis revealed that hydrolysis patterns of xylans from oat spelt, birch wood and beech wood by purified XylA were different. The XylA is determined to be an endo-beta-1,4-xylanase, as it generated mainly xylotriose and no xylose was detected among the three hydrolysates. XylA has strong hydrolytic activity towards the pentose in the hydrolysates of beech wood and birch wood xylans, but was not active to the pentose in the hydrolysate of oat spelt xylan. The crude WL-11 enzyme can efficiently hydrolyze oat spelt xylan to a series of xylo-oligosaccharides, suggesting its potential application in nutraceutical industry.

The psychrotrophs SYP-A2-3 producing the cold-adapted protease has been isolated from the bacterial samples collected from the No. 1 Glacier of China and identified as Bacillus cereus according to its morphological and physiochemical characteristics and 16s rDNA gene sequence analysis. It could grow between 0 degree C and 38 degrees C while its optimal growth temperature was 25 degrees C and the optimal temperature for its protease production was 15 degrees C. The cold-adapted protease was identified as neutral metallo-protease, the molecular weight was 34.2 kD shown by SDS-PAGE, the optimal pH and temperature for activity was 7.0-8.5 and 42 degrees C, respectively. Various fermentation conditions of its protease production were also investigated. The results showed that casein was the best nitrogen source while glucose and starch were suitable carbon source for its protease production. The initial pH of fermentation broth ranged from 6.5 to 7.0 was optimal. Under optimized conditions, the protease activity produced by SYP-A2-3 could reach 3800 U/mL and 4800 U/mL conducted in shaking flask and 5 L stirred jar experiment, respectively.