Bio-desilication of rutile concentrate and analysis of community structure in bio-desilication reactor

The original strain HY-7 was isolated from the bauxite mine drainage（BMD） taken from a reservoir in Sanmenxia Mine,Henan Province,China.The optimum temperature and pH for the growth of strain HY-7 were 30 ℃ and 7.0,respectively.The optimum UV radiating time was 20 s and the positive mutation rate was 23.0%.The growth curves show that strain HY-7 needs144 h to reach the stationary phase after its mutagenesis,which is 24 h earlier than that of the original strain.Sequence homology analysis indicated that this community consisted of mainly two branches：one sharing high homology with Paenibacillus stellifer and the other sharing high homology with Sporolactobacillus laevolacticus.The experimental results showed that the TiO2 grade of mtile concentrate increased from 78.21%to 91.80%and the recovery of TiO2 reached 95.24%after 7 d of bioleaching.The bio-desilication process can not only effectively improve the TiO2 grade of rutile concentrate but also meet the requirements of environmental protection.

Tomato Growth and Organic Acid Changes in Response to Partial Replacement of NO_3^--N by NH_4^+-N

A hydroponic experiment was conducted to study the effect of partial replacement of NO-3-N by NH4+-N on the seedling growth and organic acid content of tomato (Lycopersicon esculentum Mill.). A completely randomized design was established with three replications and five treatments, i.e., NO-3-N/NH4+-N of 100/0, 75/25, 50/50, 25/75 and 0/100. Results showed that 25% replacement of NO3--N by NH4+-N significantly (P = 0.05) improved fresh and dry weight, revealing that a proper percentage of NH4+-N was important for tomato nitrogen nutrition. This could increase the plant growth even though tomato was a crop that preferred nitrate nutrition. Also an increase in the proportion of NH4+-N in the nutrient solution led to a significant decrease (P = 0.05) in malate, citrate and fumarate. However, the 25% NH4+-N plus 75% NO3--N treatment had no significant effect (P = 0.05) on the 2-ketoglutarate, succinate or oxalic acid content, showing that only some organic acids in tomato plants were affected. Only pyruvate increased significantly (P = 0.05), and it only increased for 25% and 50% replacement of NO3--N by NH4+-N. Metabolism of these organic acids, especially malate, citrate and fumarate, should be further studied at the molecular level in vegetables applied with different nitrogen forms.

Extraction and Characterization of Biological Humic Acids from Fermented Furfural Residue

Objective] This study aimed to eliminate the negative effects brought about by continuous, long-term accumulation of sodium ions in soil on soil environ-ment. [Method] Biological humic acids （BHAs） were extracted from fermented furfural residue via alkali-dissolution and acidification. The effects of solid-liquid ratio （mass ratio of fermented furfural residue to water）, alkali concentration, extraction tempera-ture and extraction time on the content of BHA were investigated. Also its structure was characterized by FTIR. [Result] The optimal extraction conditions were as fol-lows： solid-liquid ratio of 1：7, KOH concentration of 6%, extraction temperature of 70℃ and extraction time of 1 h. Under the optimal conditions, the content of BHAs extracted was up to 8.5%. The infrared spectrum analysis indicated that BHA had more types of functional groups and lower molecular weight than commercial humic acid although they had similar structures. [Conclusion] The technique has the ad-vantages of simple operation and good stability, and is suitable for extracting BHAs. BHAs have a good prospect in developing new types of humic acid fertilizers.

Ester-Derivatized Indoles as Fluorescent and Infrared Probes for Hydration Environments

Tryptophan derivatives have long been used as site-specific biological probes. 4-Cyanotrypto- phan emits in the visible region and is the smallest blue fluorescent amino acid probe for bio- logical applications. Other indole or tryptophan analogs may emit at even longer wavelengths than 4-cyanotryptophan. We performed FTIR, UV-Vis, and steady-state and time-resolved fluorescence spectroscopy on six ester-derivatized indoles in different solvents. Methyl indole- 4-carboxylate emits at 450 nrn with a long fluorescence lifetirne, and is a promising candidate for a fluorescent probe. The ester-derivatized indoles could be used as spectroscopic probes to study local protein environments. Our measurements provide a guide for choosing esterderivatized indoles to use in practice and data for computational modeling of the effect of substitution on the electronic transitions of indole.

Effect of motilin on the contractility of gastric smooth muscle via NO pathway in guinea pigs

This study investigates the gastroprokinetic effects of motilin and erythromycin A （EM-A） and its potential mechanism in guinea pigs Carla porcellus in vitro. Guinea pig stomach strips were mounted under organ baths containing Krebs solution. Motilin, EM-A, Nω-Nitro-L-arginine （L-NNA）, L-arginine （L-AA） were added to the bathing solution in a non-cumulative way. Then the effects of motilin and EM-A was studied during electrical field stimulation （EFS） in the absence and presence of L-NNA and L-AA in the gastric anturm and fundus of guinea pigs. In addition, we observed the co-expression of motilin receptors and neuronal nitric oxide synthase （nNOS） in the gastric myenteric plexus of guinea pigs by fluo-immunohistochemistry. The results showed that the circular muscle tissues of the gastric fundus generated on-relaxations and off-contractions with the frequency of 1 - 16 Hz. The on-responses induced a relaxation, partially mediated by the release of nitric oxide （NO） because addition of L-NNA turned the relaxations into cholinergically mediated contractions. The off-contractions were also cholinergically mediated as they disappeared under non-adrenergic, non-cholinergic （NANC） conditions using atropine and guanethidine. In fundic strips, motilin and EM-A induced on-relaxation and off-contraction and both motilin （1 μmol/L） and EM-A （100 μmol/L） may significantly increased on-response and reduced off-response （P 〈 0.05）. And the effects of motilin on strip responses were significantly enhanced compared with EM-A. The on-responses could be reversed into a cholinergically mediated contraction by addition of NOS inhibitors L-NNA. In contrast, administration of substrate of NOS, L-AA, significantly increased on-relaxations and reduced cholinergic motor responses which were induced by motilin or EM-A. However D-arginine （D-AA） did not change the above response induced by motilin or EM-A. In the antral strips, motilin and EM-A only increased off-contractions. The response to motilin and EM-A in the presence of L-NNA did differ from that obtained with L-NNA alone. It showed that both motilin and EM- A could enhance off-contractions induced by L-NNA （P 〈 0.05）. Immunohistochemistry study showed that motilin receptor immunoreactive positive neurons were co-localized with nNOS positive neurons in the gastric myenteric plexus of the guinea pigs. These results suggested that motilin or EM-A modulates gastrointestinal motility which was mediated by activating gastric nervous and NO pathways in guinea pigs gastro-intestinal tract.

Effects of a low-radiotoxicity uranium salt(uranyl acetate) on biochemical and hematological parameters of the catfish,Clarias gariepinus

Specimens of Clarias gariepinus were treated with lethal(70,75,80,85,90,and 95 mg/L) and sub-lethal concentrations(8,12 and 16 mg/L) of uranyl acetate,a low-radiotoxicity uranium salt. The LC 50 value was registered as 81.45 mg/L. The protein and glycogen concentrations in liver and muscles were decreased in the fish exposed to sub-lethal concentrations. The red blood cell(RBC) and white blood cell(WBC) counts,haemoglobin(Hb) concentration and haematocrit(Hct) values were decreased. Different blood indices like mean corpuscular volume(MCV),mean corpuscular haemoglobin(MCH) and mean corpuscular haemoglobin concentration(MCHC) were negatively affected. Level of plasma glucose was elevated whereas protein was decreased. The level of calcium concentration(Ca) was declined in the blood of exposed fish whereas magnesium(Mg) remains unchanged. The activity level of glutamic-oxaloacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) was elevated in exposed fish. These effects were more pronounced in the last period of exposure and in higher concentrations. Results of the present study indicate that uranyl acetate has adverse effects on C larias gariepinus and causes changes in the biochemical and hematological parameters of the fish.

Bioavailability Improvement of SLMs Based Erythromycin Ethyl Succinate using Stearic Acid-Myrj-52-based SLM＇s

Solid lipid microparticles of erythromycin ethyl succinate were prepared using solvent evaporation method to improve its bioavailability and efficacy. The solvent was allowed to evaporate after which the various entrapments were determined; the best entrapment was used in the in vivo studies to determine the bioavailability and efficacy. This study was done with albino mice. The best entrapment obtained was 83% with a loading capacity of 2.9% （Batch D） and was used in comparison with the unformulated drug to check for the in vivo efficacy. The results show higher efficacy with the formulated drug than with the pure drug both in vitro and in vivo. The in vitro test results were better despite that some enzymes which need to act on the solid lipid microparticles were not present in the in vitro assay and could lead to a reduction in the release of the drugs. In conclusion, there was improvement in efficacy, and hence bioavailability.

Near and Mid Infrared Spectroscopy to Detect Malolactic Biotransformation of Oenococcus oeni in a Wine-Model

The aim of this work was to verify the potential of infrared （IR） spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation （MLF） occurring in a model-wine and the further cells autolysis. MLF in wine is a secondary biotransformation due to lactic acid bacteria that usually occurs spontaneou,;ly or after starter inoculation at the end of alcoholic fermentation. Nowadays, it is desirable to supply winemakers with a new rapid and non-destructive approach to monitor MLF progress and 1R spectroscopy technology appears to be suitable for this purpose. The transformation of L-malic acid into L-lactic acid was carried out by inoculating a synthetic wine with an Oenococcus oeni culture and it was monitored through microbiological and chemical methods. At the same time, Fourier transform near infrared （FT-NIR） spectral data, in diffusive transflection mode using an optic probe, and FT-IR spectra, using an germanium crystal attenuated total reflectance （ATR） cell, were collected. Principal component analysis of the spectra was able to identify absorption bands related to the key molecular modifications that took place during the L-malic acid transformation. Thus, the samples were discriminated according to the fermentation phase. Although this study is a preliminary approach, results confirm that near infrared （NIR） and mid infrared （MIR） spectroscopy could be successfully applied to detect the start of MLF and the autolysis of the lactic acid bacteria （LAB） cells.

Effect of Biochar Addition on Maize Growth and Nitrogen Use Efficiency in Acidic Red Soils

Biochar added to soil can improve crop growth through both direct and indirect effects, particularly in acidic, highly weathered soils in subtropical and tropical regions. However, the mechanisms of biochar improving crop growth are not well understood. The objectives of this study were i) to determine the crop responses to biochar addition and ii) to understand the effect of biochar addition on N use efficiency. Seven acidic red soils varying in texture, p H, and soil nutrient were taken from southern China and subjected to four treatments: zero biochar and fertilizer as a control(CK), 10 g kg-1biochar(BC), NPK fertilizers(NPK), and 10 g kg-1biochar plus NPK fertilizers(BC+NPK).15N-labeled fertilizer was used as a tracer to assess N use efficiency. After a 46-d pot experiment,biochar addition increased soil p H and available P, and decreased soil exchangable Al3+, but did not impact soil availabe N and cation exchange capacity(P > 0.05). The N use efficiency and N retained in the soil were not significantly affected by biochar application except for the soil with the lowest available P(3.81 mg kg-1) and highest exchanageable Al3+(4.54 cmol kg-1). Greater maize biomass was observed in all soils amended with biochar compared to soils without biochar(BC vs. CK, BC+NPK vs. NPK). This agronomic effect was negatively related to the concentration of soil exchangeable Al3+(P < 0.1). The results of this study implied that the liming effect of biochar improved plant growth through alleviating Al toxicity and P deficiency, especially in poor acidic red soils.

Effects of acupuncture on nutritional status in patients in a persistent vegetative state:a prospective randomized controlled study

Objective To explore the effects of acupuncture on nutritional status in patients in a persistent vegetative state.Methods A prospective randomized controlled trial was designed.A total of 66 patients in a persistent vegetative state were randomized into a control group and an observation group,with 33 cases in each group.The control group was given conventional treatment plus enteral nutrition support.The observation group was treated with additional Tiao Shen Jian Pi acupuncture therapy(acupuncture for spirit-regulating and spleen-invigorating)based on the same interventions in the control group.Both groups were treated for 8 weeks.The levels of total protein(TP),prealbumin(PA),albumin(Alb),and hemoglobin(Hb)were measured before and after treatment.The upper arm circumference and skinfold thickness of triceps brachii were measured.And the intestinal flora and fecal short-chain fatty acids contents were determined.Results After treatment,the levels of TP,PA,Alb,and Hb in the control group were decreased(P<0.05),while in the observation group,compared with those before treatment,the levels of TP,PA,Alb,and Hb had no statistical differences(P>0.05),and the levels were all higher than those in the control group(P<0.05).The upper arm circumference and skinfold thickness of triceps brachii in both groups decreased(P<0.05),and the values of these two items in the observation group were higher than those in the control group(P<0.05).In the control group,the contents of Bifidobacterium and Lactobacillus in feces decreased(P<0.05),and the content of Enterococcus increased(P<0.05).In the observation group,the contents of Bifidobacterium and Lactobacillus in feces increased(P<0.05),and the content of Enterococcus decreased(P<0.05).The differences between the two groups were statistically significant(P<0.05).In the control group,the total content of fecal short-chain fatty acids and the contents of acetic acid and butyric acid in feces decreased(P<0.05).In the observation group,the total content of fecal short-chain fatty acids and the contents of acetic acid and butyric acid in feces increased(P<0.05)and were all higher than those in the control group(P<0.05).Conclusion Acupuncture can improve nutrition-related blood indicators in patients in a persistent vegetative state and delay the decrease of upper arm circumference and skinfold thickness of triceps brachii,which may be related to the regulation of intestinal flora and fecal short-chain fatty acids contents.

Alcohol compounds in Azolla imbricata and potential source implication for marine sediments

This study investigated the composition of long-chain alkyl diols, triols, sec-alcohols, hydroxyl acids, and other hydroxylated compounds in Azolla imbricata and compared the organic alcohol components of Azolla filiculoides, Azolla microphylla, and South China Sea （SCS） sediments in order to investigate the possible indication of Azolla being the biological source of diols and triols in SCS sediment. Large amounts of diols, monohydroxy acids, and sec-alcohols with internal hydroxy groups at ω20 were detected in the three types of Azolla. Among these, 1,ω20-diol and ω20-hydroxy acid exhibited strong even-odd predominance distribution, whereas co20-sec-alcohol exhibited strong odd-even predominance distribution. In addition, small amounts of diols, triols, and dihydroxy acids with internal hydroxy groups at 9, 10 or ω9, ω 10 were detected, among which the chain length of C29 was predominate. Compounds having similar structures as those in Azolla reflected a similar biosynthetic pathway： ω20-hydroxy acid exhibiting even-odd predominance distribution is decarboxylated to ω20-sec-alcohol exhibiting odd-even predominance distribution and converted to 1, ω20-diol with even-odd predominance distribution by acyl reduction; ω9,ω10-hydroxy acid is converted to 1,20,21（1, ω9, ω10）-triol by acyl reduction, and then converted to 9,10-diol by hydrogenation and dehydration. The alcohol components in A. imbricata were clearly not the biological source of 1,13/1,14/1,15-C28, 30, 32 diols and 1,3,4-C27.29 triols in the SCS sediment. Certain marine diatoms might be the source of 1,14-C28.30 diol in inshore sediment, but the biological source of diols and triols in the SCS sediment requires further investigation.