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The flavonoid contents of different bamboo-leaf extracts and their relationships to antioxidant activity were investigated in this study by preparing nine samples using two commercially available bamboo-leaf extract products and seven bamboo-leaf extracts such as Phyllostachys edulis . A high performance liquid chromatography (HPLC) method was established to determine seven flavonoid components (orientin, isoorientin, vitexin, isovitexin, tricin, luteolin and luteoloside) in these samples, which were separated using a SymmetryShield TM RP8 column (250 mm×4.6 mm, 5 μm) under gradient-elution conditions using acetonitrile as mobile phase A and 0.5% (v/v) acetic acid aqueous solution as mobile phase B. The antioxidant activities of the samples were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging assays, with half inhibitory concentration (IC 50 ) as an indicator and the butylated hydroxytoluene (BHT) and tert -butylhydroquinone (TBHQ) antioxidants as positive controls. Pearson correlation was then used to analyze the relationship between flavonoid content and antioxidant activity. The HPLC method was found to be accurate and reliable for determining the flavonoid contents of the bamboo-leaf extracts. The seven flavonoids were well separated, and good linear relationships were exhibited (correlation coefficients ( R 2 )≥0.9990). Furthermore, the contents of the seven flavonoids in the bamboo-leaf extracts ranged from 14.97 to 183.94 mg/g, with the highest content of 183.94 mg/g recorded for Phyllostachys edulis . The bamboo species exhibited significantly different flavonoid contents, with Phyllostachys edulis showing the highest orientin, isoorientin, and vitexin levels of 38.45, 101.30, and 9.42 mg/g, respectively. Moreover, the bamboo-leaf extracts exhibited IC 50 values of 78.23-179.41 mg/L for DPPH-radical-scavenging, while values of 203.48-1250.81 mg/L were recorded for hydroxyl radicals. The Phyllostachys edulis leaf extract exhibited the strongest antioxidant activity, with the lowest IC 50 values of 78.23 and 203.48 mg/L for DPPH and hydroxyl, respectively; it showed greatly significant for the further development and application of Phyllostachys edulis . Finally, the relationships between flavonoid content and the DPPH- and hydroxyl-radical-scavenging activities (based on the IC 50 values) were correlated, which revealed that the orientin and isoorientin contents are closely related to the antioxidant activities of the bamboo-leaf extracts. Consequently, the orientin and isoorientin contents can be used as indicators for evaluating the antioxidant activities of bamboo-leaf extracts.

Thermochemical pretreatment of lignocellulosic biomass is a critical step in obtaining high yields of cellulose and hemicellulose-derived sugars to realize effective utilization of cellulose in renewable biofuels. The pretreatment process can quickly remove hard dissolving lignin and the physical separation of hemicelluloses in the cell wall while changing the chemical composition in plant cell wall, so as to increase the production of lignocellulose. Research with medium of sulfuric acid (H(2)SO(4)), dilute alkali (NaOH) and glycerin, and at different pretreatment temperature (117 and 135 ℃ in sulfuric acid (H(2)SO(4))and dilute alkali (NaOH) , 117 ℃ in glycerin) analyzed and compared the main changes of chemical composition before and after the bamboo processing, and further confirmed that the mechanism of the chemical conversion after chemical pretreatment of bamboo through the Fourier infrared spectrum. The results showed that the output cellulose increased significantly after the thermochemical pretreatment. The change rules for yield of cellulose and the removal rate of lignin under the different pretreatment condition had been indicated dilute alkali (NaOH) treatment effect is better than that of dilute acid (H(2)SO(4)) and glycerin. In addition, the effect is more remarkable under the condition of 135 ℃ than 117 ℃ in the same medium. The changes of degradation degree of hemicellulose with different processing conditions were the same. The infrared spectrum analysis provided that C—O—C asymmetric stretching vibration peak appeared in cellulose decomposition after heat treatment, and it is the obvious steep fall in hemicelluloses infrared absorption characteristic peaks, benzene ring characteristic absorption peak of lignin has been abated. It is prove that yield of cellulose increased significantly, degradation trend of hemicelluloses is obviously, removal effect of lignin has also been better. The analysis results of Fourier infrared spectrum are consistent with the standard measurement.

Objective: To evaluate of bamboo charcoal powder( BCP) on the lipid profile and mechanism in hyperlipidaemia model rats., Methods: 40 male Sprague-Dawley( SD) animals of 4 weeks old were randomly assigned into five groups: the control group fed with low-fat diet; the model control group and the test group( 2. 81, 5. 62, 11. 24 g /kg). Each group gived BCP or distilled water correspondingly, the total administration duration was 90 consecutive days. After the blood samples were collected, liver, kidneys, and white adipose around bilateral epididymis and kidneys were excised and weighed. Serum biomarkers of liver and kidney function were detected. The activities of TC, TGand MDA, T-AOC, CAT, SOD of liver were determined by corresponding test kits according to the manufacturer's protocols. Livers were also further detected by macroscopic and microscopic examinations., Results: After 90 days of treatment, the weight of rats more than 4 weeks, liver weight and percentage of body fat, serum AST, TG and VLDL, hepatic MDA, TG, TC and liver steatosis in the model control group was all increased compared with the negative control group, indicating that the model has been successfully built. It showed that the weight of rats, liver weight and white adipose weight, serum AST, TG and VLDL, hepatic MDA, TC and liver steatosis in the three dose group was all decreased. The hepatic SOD, CAT, T-AOC in the three dose groups were all increased., Conclusion: The BCP could reduce the accumulation of body fat, inmprove blood lipid and hepatic steatosis in hyperlipidemia model rats.

Objective: To study the chemical constituents of Indocalamus latifolius leaves., Methods: The chemical constituents were isolated and purified with silica column chromatography and gel chromatography. Their structures were identified by physicochemical properties and various spectroscopic methods including NMR spectrum, MS, UV, etc., Results: Fourteen compounds were isolated from the ethyl acetate part as isovitexin (1), vitexin (2), orientin (3), homoorientin (4), vanillic acid (5), chlorogenic acid (6), caffeic acid (7), ferulic acid (8), friedelin (9), tricin (10), tricin-7-O-beta-D-glucopyranoside (11), fernenol (12), luteolin-6-C-glucopyranoside (13) and quercetin-3-O-glucopyranoside (14)., Conclusion: All compounds are isolated from this plant for the first time.

Taking pure Oligostachyum lubricum forest as test object, this paper studied the matured and withered leaves carbon (C), nitrogen (N), and phosphorus (P) stoichiometry and N and P resorption patterns of 1-3 years old stands at the densities of 24600-29800 stem hm-2 (D, ), 37500-42600 stem hm-2 (D2 ), 46500 - 52800 stem hm-2 (D3), and 76500 - 85500 stem hm-2 (D4). With increasing stand density, the matured leaves C, N, and P contents and withered leaves C and P contents had an overall decrease, the withered leaves N content decreased after an initial increase, and the matured leaves C content at density )4 decreased dramatically. The leaf C/N and C/P ratio increased with increasing stand density, whereas the leaf N/P ratio increased first but decreased then. At stand densities D3 and D4, the leaf N and P utilization efficiencies were significantly higher than those at D, and D2. With increasing stand density, the leaf N resorption capacity increased after an initial decrease, while the leaf P resorption capacity increased steadily. At stand densities D,-D3, the matured leaves N/P ratio was 16.24-19.37, suggesting that the P limitation occurred, leaf establishment increased, and population increase and expansion enhanced. At density D4, the matured leaves N/P ratio was 13.42-15.74, implying that the N limitation strengthened, leaf withering and defoliation increased, and population increase inhibited. All the results indicated that O. lubricum could regulate its leaf C, N and P contents and stoichiometry and enhance the leaf N and P utilization efficiency and resorption capacity to adapt to the severe competition of environment resources at high stand density. In our experimental condition, 46500-52800 stem hm-2 could be the appropriate stand density for O. lubricum management.

A simple and efficient method based on solid-phase extraction (SPE) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the determination of butylene fipronil, chlorpyrifos, chlorantraniliprole, fipronil, imidacloprid, indoxacarb and phoxim residues in bamboo shoots. The sample was extracted with acetonitrile and purified by a primary secondary amine (PSA) solid-phase extraction cartridge. The detection of targets was performed by HPLC-MS/MS with multiple reaction monitoring (MRM) mode. All the seven pesticides were completely separated in 15 min with an excellent linear relationship. The limits of detection and the limits of quantification for the seven pesticides were 0.02-0.5 microg/kg and 0.08-1.5 microg/kg, respectively. The recoveries of the seven pesticides spiked in a bamboo shoot sample at the levels of 4, 8, 32 microg/kg were in the range from 76.0% to 102.6% (the RSD < or = 11.0%, n = 3). The method was successfully applied to the real bamboo shoot samples. The method has high accuracy and sensitivity, and is simple and quick. It can meet the requirement of the simultaneous determination of the seven pesticides in bamboo shoots.

Large-area flowering of the giant pandas' staple food is an important factor which can influence their survival. Therefore, it is necessary to predict the bamboo flowering. Foping Nature Reserve was taken as the study area. The research selected the giant pandas' staple-food bamboos Bashania fargesii, Fargesia qinlingensis and Fargesia dracocephala with different flowering situations (i. e., flowering, potential flowering, non-flowering with far distance) to measure the spectral reflectance of bamboo leaves. We studied the influence of bamboo flowering on the spectral features of three bamboo species through analyzing the original spectral reflectance and their red edge parameters. The results showed that (1) the flowering changed the spectra features of bamboo species. The spectral reflectance of B. fargesii shows a pattern: flowering bamboo < potential flowering bamboo < non-flowering bamboo with far distance, while F. qinlingensis and F. dracocephala show the different pattern: flowering bamboo > or = potential flowering bamboo > non-flowering bamboo with far distance. Among three bamboo species, F. dracocephala showed the greatest change, and then F. qinlingensis. (2) After bamboo flowering, the red edge of B. fargesii has no obvious shifting, while the other two bamboos have distinctive shifting towards the shorter waves. The study found that the original spectral feature and the red edge all changed under various flowering states, which can be used to provide the experimental basis and theoretic support for the future prediction of bamboo flowering through remote sensing.

Based on the requirement of National Implementation Plan for the Stockholm Convention on Persistent Organic Pollutants (NIP), six industries including pulp and paper industry have been set as the priority key sectors to implement the best available technology and best environmental practice (BAT/BEP) within a specific time for UPOPs reduction. Non-wood pulping has always played important role in virgin pulp production in China, its elemental chlorinated bleaching process has been confirmed as main source of Dioxin emission for the sector. As the signature party of Stockholm Convention and long time existing country of non-wood pulping, identification of Dioxin emission situation is significant importance to China to committee the obligation of Stockholm Convention. The Dioxin concentrations in outflow water of bamboo, straw, reed, and bagasse pulping processes (chlorination alkaline extraction hypochlorite, CEH) are 41.8 pg x L(-1), 72.7 pg x L(-1), 7.46 pg x L(-1), and 19.7 pg x L(-1) respectively, which are all around the national waste water discharge standard (30 pg x L(-1)). But relevant data will easily exceed national standard while the limitation of unit water consumption for pulp making is decreased. So the application of best available techniques/best environmental practices (BAT/BEP) is very necessary to improve relevant mills up to the above standard, and proceed the sector meeting the national and international requirements for Dioxin emission. At the same time, the text calculates emission factors on bamboo, straw, reed and bagasse pulp making process through whole process monitoring, which will provide meaningful reference for increasing relevant factors in UNEP Toolkit.

A procedure for the separation and preconcentration of bismuth was developed in a sequential injection system by employing bamboo carbon as sorbent. The detection was facilitated by both hydride generation atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry. With a sample volume of 1 mL, a detection limit of 13 ng x L(-1) was obtained, along with a precision of 0.9% (0.3 microg x L(-1), n = 9) with detection by HG-AFS, and a detection limit of 10 ng x L(-1) along with a precision of 2.8% (0.3 microg x L(-1), n = 5) was achieved with detection by ICP-MS. The present system was validated by analyzing a certified reference material of river sediment (CRM 320), and spiking recovery of bismuth in human whole blood was performed with hydride generation atomic fluorescence spectrometry. No significant difference was identified in the results of bismuth detection in blood samples by hyphenating the present solid phase extraction system with detection by hydride generation atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry.

The photodegradation process of bamboo involves very complex chemical reactions. In the present study, surface deterioration of Moso bamboo (Phyllostachys pubescens Mazel) was carried out by a xenon fade meter which can simulate sunlight irradiation, and Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopic (XPS) techniques were used to characterize the resulting changes in the chemical structure and composition of bamboo surface. XPS results showed that light irradiation resulted in significant increases in oxygen (O) content and O/C ratio. Besides, changes were also identified from the detailed C(ls) spectra, with a remarkable decrease in C1 component (C-C) and simultaneous increases in the components of C2 (C-O), C3 (C = O) and C4 (O-C = O), suggesting that the carbon atoms at bamboo surface were highly oxidized. FTIR results showed that lignin was susceptible to light irradiation and was significant degraded after treatment, as indicated by remarkable decreases in the intensity of lignin associated bands (e. g. 1 604, 1 512 and 1 462 cm(-1)). This was accompanied by the formation of new carbonyl compounds as shown by an obvious increase in the intensity of non-conjugated carbonyl group at 1 735 cm(-1), which further indicated the photo-oxidation of bamboo surface. The polysaccharides (cellulose and hemicellulose) components, however, were less influenced by light irradiation, and their relative content at bamboo surface increased significantly due to lignin degradation.

Sixty rats were randomly divides into six groups. Blood stasis model was set up by sc isoprenaline, and different dose of BLE (15 mg/kg, 30 mg/kg and 60 mg/kg) were iv. The effects of BLE on rat's blood viscosity, plasma viscosity, FIB, ESR, TK, electrophoresis times and HCT were measured by automatic analysis system. Sixty mice were randomly divided into six groups, and the serum cholesterol of the high cholesterol's mice was obtained by eyepit vein and measured. The results showed that BLE (15 mg/kg, 30 mg/kg and 60 mg/kg) could reduce blood viscosity, plasma viscosity, FIB, ESR, TK, HCT and increase the speed of electrophoresis time in blood adhesion model, and BLE (22.5 mg/kg, 45 mg/kg, 90 mg/kg) could significantly reduce serum cholesterol of the high cholesterol's mice.