Objective:To evaluate the effect of agar-oliogsaccharides (mainly containing agarobiose) on blood glucose level and oxidation-antioxidation status in alloxan-induced diabetic mice. Method: The inhibitory activity of agarobiose on ?-glucosidase was investigated. Alloxan was used to establish non-obese diabetic (NOD) mice model. After 14 d administration of agarobiose, blood glucose, MDA, SOD, GSH and GSH-Px levels were determined. Results:Agarobiose showed inhibitory activity on ?-glucosidase with IC50=1.39 mg/ml, Ki=0.52 mg/ml. In a certain concentration (200-400 mg/kg bw), agaro-oligosaccha- rides reduced the blood glucose level remarkably, and the oxidative indices were also improved in heart, liver, lung and brain. The blood glucose level (P

This study is designed to investigate the anti-tumor and anti-angiogenesis mechanism of carrageenan oligosaccharides. The effects of carrageenan oligosaccharides on basic fibroblast growth factor (bFGF) induced cell proliferation, heparanase activity and bFGF binding ability were evaluated in human cervical cancer cells (HeLa) and human umbilical vein endothelial cells (HUVEC). Results indicate that, at rational concentrations, carrageenan oligosaccharides showed low cytotoxic effect. At relatively low concentrations (0.2-200 microg x mL(-1)), these oligosaccharides could competitively bind bFGF and inhibit bFGF induced cell proliferation. In these samples, oligo-lambda-carrageenans (dp2-8) were the most potent bFGF antagonists. At concentration of 20 microg x mL(-1), their inhibitory ratio reached to 30%. The heparanase enzyme assay revealed that three kinds of carrageenan oligosaccharides showed different inhibitory activities to two cell lines. For HeLa cell, oligo-lambda-carrageenans showed highest inhibitory effect, but for HUVEC, oligo-kappa-carrageenans (dp9-17) were the best inhibitors. Current observations demonstrated that the biological activities of carrageenan oligosaccharides are closely related to the molecular weight, carbohydrate structure and the content and linking position of sulfur groups. Carrageenan oligosaccharides with high sulfate fraction, 2-8 units saccharide size and suitable molecular structure are able to achieve potent heparin sulfate-like compounds.

Objective Agaro-oligosaccharides have been proved to possess the antioxidative ability in vitro. This work focus on the preparation of agaro-oligosaccharides and their antioxidant effect in vivo. Method Agaro-oligosaccharides were hydrolytically obtained and the activated carbon column was used to purify the oligosaccharides. The antioxidative effects of the 10 % ethanol eluted fraction on tissue peroxidative damage induced by carbon tetrachloride (CCl 4) was also investigated in rat. Result Agarobiose of high purity was consequently eluted from chromatography in the fractions of 5 % and 8 % ethanol, agarotetraose and agarohexaose in 10 % to 15 % ethanol, as well as high degree of polymerization (DP) oligosaccharides in 25 % ethanol. The antioxidative results indicated that agaro-oligosaccharides could elevate the activities of SOD, GSH-Px and decrease the level of MDA, GPT, GOT significantly. At a dose of 400 mg?kg~ -1, MDA level was reduced 44 % and 21 % in liver and heart, the activities of SOD and GSH-Px would amount to the peak value in liver and serum, while GPT level was decreased 22 % in serum. Conclusion The purity of agaro-oligosaccharides with different range of DPs was improved by activated carbon column, which possesses the property of different absorbance ability towards oligosaccharides with various DPs and high isolating capability. The animal test also indicated that agaro-oligosaccharides could inhibit the oxidative damage in vivo.

A method was developed to elucidate the structures of sulfated oligosaccharides through establishment of an effective reversed phase ion pair ultra-performance liquid chromatography coupled with electrospray ionization time of flight mass spectrometry( RPIP-UPLC-ESI-TOF-MS). Heptylamine (20 mmol/L,pH4) has been selected as the ion-pairing agent.κ-Carrageenan oligosaccharides have been separated on BEH C_(18) column using MeOH/H_2O with 25% heptylammonium formate as eluent in linear gradient mode. Mass spectra were obtained by ESI-Q-TOF-MS in both positive and negative modes. κ-Carrageenan oligosaccharides were well separated up to pentatetrasaccharide,and ESIMS analysis for κ-carrageenan oligosaccharides up to hepta-cosasccharide. The results showed that all acid hydrolyzed κ-carrageenan oligosaccharides were odd sugars,which was further confirmed by polyacrylamide gel electrophoresis ( PAGE). The characteristic fragmentation pattern of ion-pair oligosaccharides in mass spectra can be applied for rapid structure identification.

Various cancers have seriously threatened human' s health. Screening newer and more effective anticancer agents from natural sources to cure these diseases is the focus in research. As novel sources of potential medicine, a number of metabolites isolated from endophytic fungi have been proved to have anticancer bioactivity. Usually, these endophytic fungi have special biochemical pathway and they can accumulate anticancer agents in cultures such as taxane, alkaloids, cytochalasins, podophyllotoxin, brefeldin A and so forth. The research advance on anticancer agents purified from endophytic fungi is expatiated systemically. In addition, the strategy of screening anticancer agents as well as the prospect on this area is introduced briefly.

This study is to investigate the protective effect of astaxanthin against injured hepatocyte L-02 cells induced by sodium azide (NaN3) and reveal the possible mechanisms. Hepatocyte L-02 cells were exposed to 100 mmol.L-1 NaN3 with various concentrations of astaxanthin pre-incubated, then the cell viability was measured by MTT method; The level of reactive oxygen species (ROS) was determined by DCFH-DA method; The changes of mitochondrial membrane potential (MMP) and apoptosis ratio were detected by JC-1 method and Annexin V-FITC/PI double stain method, respectively. Results showed that after cells were exposed to 100 mmol.L-1 NaN3 for 3 hours, the cell viability significantly decreased; ROS level and the percentage of late phase apoptosis increased obviously; MMP was also declined. When cells were pretreated with astaxanthin, the cell damage and late phase apoptosis ratio reduced and MMP was maintained. However, the level of ROS showed insignificant decrease (P>0.05). The beneficial concentration of astaxanthin in improving cell viability and MMP was not in a dose dependent manner and the most effective of which was 0.10 nmol.L-1 (P<0.01). In order to reveal its possible non-antioxidant mechanism, mitochondrial membrane was imitated and H+ transferring function of astaxanthin was also detected by bilayer lipid membrane (BLM) method. Results showed that 2.0% astaxanthin could transfer H+ efficiently. These suggested the mechanisms of astaxanthin in protection of hepatocyte L-02 cells not via its ROS quenching capability but via its H+ transferring function, which improved the mitochondrial function and had the sequence biology effects.

The effect of astaxanthin on N(Ω)-nitro-L-arginine methyl ester (L-NAME) induced preeclampsia disease rats was investigated. Thirty pregnant Spraque-Dawley rats were randomly divided into three groups (n = 10): blank group, L-NAME group and astaxanthin group. From day 5 to 20, astaxanthin group rats were treated with astaxanthin (25 mg x kg(-1) x d(-1) x bw(-1)) from pregnancy (day 5). To establish the preeclamptic rat model, L-NAME group and astaxanthin group rats were injected with L-NAME (125 mg x kg(-1) x d(-1) x bw(-1)) from days 10-20 of pregnancy. The blood pressure and urine protein were recorded. Serum of each group was collected and malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide synthase (NOS) activities were analyzed. Pathological changes were observed with HE stain. The expression of NF-κB (nuclear factor kappa B), ROCK II (Rho-associated protein kinase II), HO-1 (heme oxygenase-1) and Caspase 3 were analyzed with immunohistochemistry. L-NAME induced typical preeclampsia symptoms, such as the increased blood pressure, urinary protein, the content of MDA, etc. Astaxanthin significantly reduced the blood pressure (P < 0.01), the content of MDA (P < 0.05), and increased the activity of SOD (P < 0.05) of preeclampsia rats. The urinary protein, NO, and NOS were also decreased. HE stain revealed that after treated with astaxanthin, the thickness of basilal membrane was improved and the content of trophoblast cells and spiral arteries was reduced. Immunohistochemistry results revealed that the expressions of NF-κB, ROCK II and Caspase 3 in placenta tissue were effectively decreased, and HO-1 was increased. Results indicated that astaxanthin can improve the preeclampsia symptoms by effectively reducing the oxidative stress and inflammatory damages of preeclampsia. It revealed that astaxanthin may be benefit for prevention and treatment of preeclampsia disease.

Objective: To study the inhibition effect of agaro-oligosaccharide (AOS) on neovascularization and its mechamism. Method: The anti-angiogenic effect in vivo was evaluated on chicken chorioallantoic membrane (CAM) model. Cytotoxic activity of AOS was demonstrated by inhibition of several human cell lines by MTT assay. The apoptosis of HUVECs induced by AOS was examined by Hoechst staining assay and quantified by flowcytometry. Results: In CAM, AOS caused dose-dependent decrease on the vascular density and adversely affected capillary plexus formation. Different cytotoxic sensitivities were observed for AOS towards several kinds of cell lines, and HUVECs were more sensitive. Moreover, the growth inhibitory activity was correlated with induction of apoptosis. Flowcytometric analysis also revealed that AOS arrested the cell cycle progression at S phase. Conclusion: Agaro-oligosaccharide possesses the anti-angiogenic effects, which are associated with apoptosis induction of endothelial cells.

Objective Since the discovery of multiple bioactivities of agarobiose oligomers, the establishment of quantitative analysis of agarobiose oligomers obtained under different hydrolysis modes would be of much importance. Methods Agarobiose oligomers ranged from biose, tetraose, hexaose, octaose, to decaose were isolated and purified by gel chromatography on Sephadex column. The agarobiose oligomers were separated in RP-HPLC after introducing ?-naphthylamine into compounds. Results Each oligomer could be quantified with good linearity and the lowest detection limit reached 0.1～2 ?g?mL -1. The chromatograms profiles under different hydrolysis modes(HCl, citric acid, solid acid, and hydroxyl radical degradation)showed that the content of agarobiose could reach more than 57.8 % using solid acid hydrolysis with best yield of 33.2 % . While HCl could degrade agar into a series of agaro-oligosaccharides from biose to decaose. The yield of oligosaccharides was low if hydrated by citric acid. The method of Fenton degradation could increase the speed of hydrolysis, but the products were more complex. Conclusion The method established here could be useful for analysis of hydrolysates of oligomers under different hydrolysis modes.

A method of direct injection and liquid chromatography coupled with tandem mass spectrometric (LC-MS / MS) was developed for simultaneous determination of 5 aniline compounds including aniline, 3-nitroaniline, 4-nitroaniline, 2,6-dichloro-4-nitroaniline and hexanitrodiphenylamine in drinking water and source water. The samples were filtered using a 0. 22-μm polyethersulfone membrane prior to HPLC analysis. Five target compounds were chromatographically separated on an HSS T3 column with gradient elution. Chromatographic data were acquired by tandem mass spectrometric detection in multiple reaction monitoring (MRM) mode, and thus favorable resolutions of all target compounds were achieved within 4 min. Under the optimal analytical conditions, the peak area of each analyte and its concentration had a good correlation within the linear range (R≥0. 995). The limit of detection (LOD) and limit of quantification (LOQ) of the method were 0. 773-1. 88 μg / L (S / N=3) and 2. 58-6. 27 μg / L (S / N=10), respectively. The intra- and inter-day relative standard deviations ( RSDs) of the mix standard solution were 0. 8% -1. 9% and 3. 3% -4. 9% , respectively. The spiked recoveries of the analytes were 84. 1% -105% and the RSDs of the spiked samples were 1. 0% -3. 1% . This proposed method was applied in the analysis of 35 samples from drinking water, source water and surface water, which indicated that the novel LC-MS / MS method could detect 5 aniline compounds in water without any complicated sample pretreatment in an accurate, sensitive and rapid way, and it also could provide technique support for evaluation of the contamination caused by aniline compounds.