[Pharmacokinetics and tissue distribution of four components from root bark of Caesalpinia decapetala in rats by UPLC-MS/MS].

To identify the pharmacodynamic material basis of root bark of Caesalpinia decapetala extract and clarify the dynamic changes and distribution characteristics of the compounds in vivo.UPLC-MS/MS was used for simultaneous determination of 3-deoxysappanchalcone, isoliquiritigenin, protosappanin B, and protosappanin B-10-O-ß-D-glucoside in plasma, heart, liver, spleen, lung, kidney, stomach and duodenum of rats, to further study the pharmacokinetics and tissue distribution of root bark of C.decapetala extract in rats.Statistical analysis of obtained data demonstrated that the established analytical methods of the four components in biological matrix met the requirements of biological sample determination.The pharmacokinetic parameters showed that the t_(1/2 z), T_(max), C_(max), AUC_(0-t), MRT_(0-t), and CL_(z/F) of each component were 4.57-13.47 h, 0.22-0.51 h, 27.60-6 418.38 µg·L~(-1), 112.45-11 824.25 h·µg·L~(-1), 3.89-9.01 h, and 9.85-96.87 L·h~(-1)·kg~(-1), respectively.The results of tissue distribution revealed that at different time points, the components were widely but unevenly distributed in the body.Specifically, they were more distributed in the stomach and duodenum, followed by liver, spleen, lung, and kidney, and the least distribution was observed in the heart.

Remediation of petroleum hydrocarbons-contaminated soil: Analysis based on Chinese patents.

Increasing soil petroleum hydrocarbons (PHs) pollution have caused world-wide concerns. The removal of PHs from soils mainly involves physical, chemical, biological processes and their combinations. To date, most reviews in this field based on research articles, but limited papers focused on the integration of remediation technologies from the perspective of patents. In this study, 20-years Chinese patents related to the remediation of soil PHs were comprehensively analyzed. It showed an increasing number of patent applications and the patents' quantity were positively correlated with Chinese GDP over the years, suggesting the more the economy developed the more environmental problems and corresponding solutions emerged. In addition, chemical technologies were mostly used in a combination to achieve faster and better effects, while the physical technologies were often used alone due to high costs. In all PHs remediation techniques, bacteria-based bioremediation was the most used from 2000 to 2019. Bacillus spp. and Pseudomonas spp. were the most used bacteria for PHs treatment because these taxa were widely harboring functions such as biosurfactant production and hydrocarbon degradation. The future research on joint technologies combining microbial and physicochemical ones for better remediation effect and application are highly encouraged.

[Effects of long-term straw returning on distribution of aggregates and nitrogen, phosphorus, and potassium in paddy]. / é•¿æœŸç§¸ç§†è¿˜ç”°å¯¹æ°´ç¨»åœŸå›¢èšä½“åŠæ°®ç£·é’¾åˆ†é çš„å½±å“.

In order to understand the composition and stability of soil aggregate in paddy filed, as well as the changes of soil aggregate-associated nitrogen (N), phosphorus (P) and potassium (K) after straw addition combined with chemical fertilization, soil samples were collected from a 34-year positioning experiment with three treatments, including no chemical fertilizer (CK), chemical fertilizer only (NPK), and straw addition plus chemical fertilizer (NPKS). The composition of water-stable aggregates at the soil layers of 0-20 cm and 20-40 cm were analyzed with the wet sieving method, as well as the distribution characteristics, contribution rate and activation rate of soil aggregate-associated N, P, and K. Results showed that the fractions of >2 mm and 0.25-1 mm aggregates dominated the soil water-stable aggregates in paddy field, while the contribution of <0.053 mm aggregates was lowest. Compared with CK, NPKS treatment increased the contents of >2 mm and 1-2 mm aggregates at the layers of 0-20 and 20-40 cm, and reduced the contents of 0.053-0.25 mm and <0.053 mm. Similar result in NPK treatment was observed at the layer of 0-20 cm. Compared with tat under the NPK treatment, mean weight diameter (MWD) and geometric mean diameter (GMD) increased by 3.9%-15.5% and 6.3%-41.7% in NPKS treatment, respectively. However, the unstable aggregate index (ELT) reduced by 5.7%-28.7% in the NPKS treatment. NPKS significantly increased the contents of total N (TN), available P (AP), and available K (AK) in soil aggregates, especially in the >0.25 mm aggregates. There were no significant diffe-rences about alkali-hydrolysable N (AN) and total K (TK) between NPK and NPKS treatments. The nutrient contribution of soil aggregates in paddy field was affected by aggregate composition. NPKS significantly increased the contribution of AN, AP, and AK within >1 mm aggregates. In all, straw addition combined with chemical fertilizer could increase the stability of soil aggregates at the layers of 0-20 cm and 20-40 cm, and increase the contents of soil aggregate-associated N, P and K, especially for the >1 mm aggregates. Our results provided insights into ensuring soil quality and sustainable development of resources in paddy field by adjusting the ratio of soil C to N.

[Analysis of Spatial Distribution and Influencing Factors of Nitrogen and Phosphorus Fertilizer Application Intensity in Chengdu Plain].

The spatial distribution of fertilization intensity and its influencing factors are significant for the accurate management of fertilization and pollution prevention and control. Previous studies are mostly limited to the discussion of human factors that influences the spatial distribution of fertilization intensity while ignoring natural geographical factors. Based on the chemical fertilizer survey data collected from 23492 sites in Chengdu Plain and combined with Geostatistics analysis and Geographic Information System (GIS) technology, the spatial distribution characteristics and influencing factors of average nitrogen and phosphorus fertilizer application intensity from 2010 to 2015 in this region were explored. The results show that:① the average annual application intensity of nitrogen and phosphorus fertilizer in the study area from 2010 to 2015 is generally in the low and medium risk intensity of 120-360 kg·hm-2 and 60-180 kg·hm-2. The high risk intensity is mainly distributed in the grain (fruit) and vegetable growing areas such as Pidu, Pengzhou, Shifang, Longquanyi and Jintang, while the relatively low value areas are mostly distributed in the south and northeast. ② the nugget coefficients of nitrogen and phosphorus fertilizer application intensities are 66.17% and 41.60%. Their spatial distribution is determined by structural and random factors, showing a moderate spatial autocorrelation. ③ both human and natural factors have significant effects on the application intensity of nitrogen and phosphorus fertilizer. The crop type (fine classification) can explain the spatial variation of nitrogen fertilizer and phosphorus fertilizer respectively by 12.90% and 25.10%, which is the main controlling factor affecting the spatial distribution of nitrogen and phosphorus application intensity; the importance of soil parent material is second only to the planting crop type, and the independent explanation ability of phosphorus application intensity is about 3.6 times higher than that of nitrogen application intensity. When the type of planting crop plays a decisive role, the soil parent material still deeply restricts and affects the spatial distribution of nitrogen and phosphorus fertilizer application intensity in the study area. Therefore, the comprehensive effects of planting crop types and soil parent materials should be considered in fertilization management and environmental risk analysis, and the effects of soil parent material should also be taken into account in the application of phosphate fertilizer.

[Effects of corn-based cropping systems on phosphorus fractions and availability in red soil]. / çŽ‰ç±³ç§æ¤åˆ¶åº¦å¯¹çº¢å£¤ç£·ç´ å½¢æ€åŠå ¶æœ‰æ•ˆæ€§çš„å½±å“.

To clarify the effects of corn-based cropping systems on phosphorus (P) fractions and availability in red soil, we measured P fractions and availability of topsoil (0-20 cm) and subsoil (20-40 cm) in abandoned farmland (control) and three corn-based cropping systems (corn continuous cropping, zucchini-corn rotation and pea-corn rotation), respectively. The results showed that total P, available P contents and P activation coefficient in topsoil were higher than those in subsoil. The value of relative P parameters in topsoil of pea-corn rotation was the highest among all cropping systems. Organic P was the main P fraction in red soil, accounting for 57.8%-81.1% (topsoil) and 74.3%-85.5% (subsoil) of total P. Except for pea-corn rotation soil, sodium hydroxide extractable P (NaOH-P) was the main P fraction in other cropping systems. The contents of water-soluble P (H2O-P) and sodium bicarbonate extractable P (NaHCO3-P) with high availability were lower than other P fractions, only accounting for 0.3%-2.1% (topsoil) and 1.7%-10.0% (subsoil) of total P. The pea-corn rotation soil had the highest hydrochloric acid extractable P (HCl-P) content in topsoil and subsoil, and significantly differed from other cropping systems. The contents of available P, sodium bicarbonate extractable organic P (NaHCO3-Po), sodium hydroxide extractable organic P (NaOH-Po) and hydrochloric acid extractable inorganic P (HCl-Pi) were significantly correlated with pH, cation exchange capacity, iron-aluminum oxides and soil texture. In conclusion, pea-corn rotation was the most suitable system to improve P availability of red soil in Panxi area.

Cadmium and lead mixtures are less toxic to the Chinese medicinal plant Ligusticum chuanxiong Hort. Than either metal alone.

Agricultural production of Ligusticum chuanxiong Hort. is often affected by heavy metal pollution in soil, especially mixtures of cadmium (Cd) and lead (Pb). We assessed metal-induced phytotoxicity in L. chuanxiong by exposing the plants to soil treated with Cd, Pb, or Cd/Pb mixtures. A combined Cd/Pb treatment alleviated the inhibition in plant growth, photosynthesis, and secondary metabolite generation seen in single-metal exposures in three of the four combinations. Most combined Cd/Pb treatments resulted in preferential uptake of magnesium, copper, and nitrogen in underground plant parts and accumulation of phosphorus and calcium in aboveground plant parts, thereby leading to improvements in photosynthetic potential. Compared with single-metal exposures, combined Cd/Pb treatment significantly decreased the contents of Cd by 16.67%-40.12% and Pb by 10.68%-21.70% in the plant, respectively. At the subcellular level, the Pb presence increased the Cd percentage associated with cell wall from 64.79% to 67.93% in rhizomes and from 32.76% to 45.32% in leaves, while Cd reduced Pb contents by 9.36%-46.39% in the subcellular fractions. A combined Cd/Pb treatment decreased the contents of water- and ethanol-extractable metal forms and increased the contents of acetic acid- and hydrochloric acid-extractable forms. The lower toxic effects of the Cd/Pb mixture in L. chuanxiong were associated with photosynthetic potential, subcellular distribution, the chemical forms of Cd and Pb, and synthesis of secondary metabolites. These findings are useful for plant production strategies in soils contaminated by heavy metals.

Using the UPLC-ESI-Q-TOF-MSE method and intestinal bacteria for metabolite identification in the nonpolysaccharide fraction from Bletilla striata.

Bletilla striata (Thunb.) Reichb. f. (Orchidaceae), also known as Bai-ji, is a traditional Chinese herb that is widely used in Asia to treat hematemesis, hemoptysis, traumatic bleeding and other similar disorders. Most studies have focused on the pharmacological activities of polysaccharide extracts from B. striata. Our previous studies found that the nonpolysaccharide fraction from B. striata extract also has a hemostatic effect; however, the active constituents responsible for this pharmacological action are unclear. Thus, the metabolic profiles of the nonpolysaccharide fraction were investigated in Sprague-Dawley rats and intestinal bacteria models using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Mass data were acquired by the MSE method. Eight components including five prototypes and three metabolites were identified in rat biofluids after oral administration of the nonpolysaccharide fraction. The parent compounds underwent various metabolic processes, including hydrolysis, deglucosylation, glycosylation and sulfate conjugation. The results not only reveal the possible metabolic pathway, but also indicate the potential pharmacological components. Further mechanistic studies using nonpolysaccharide compounds of the B. striata extract are required to obtain potential candidate compounds.

Nitric oxide induces monosaccharide accumulation through enzyme S-nitrosylation.

Nitric oxide (NO) is extensively involved in various growth processes and stress responses in plants; however, the regulatory mechanism of NO-modulated cellular sugar metabolism is still largely unknown. Here, we report that NO significantly inhibited monosaccharide catabolism by modulating sugar metabolic enzymes through S-nitrosylation (mainly by oxidizing dihydrolipoamide, a cofactor of pyruvate dehydrogenase). These S-nitrosylation modifications led to a decrease in cellular glycolysis enzymes and ATP synthase activities as well as declines in the content of acetyl coenzyme A, ATP, ADP-glucose and UDP-glucose, which eventually caused polysaccharide-biosynthesis inhibition and monosaccharide accumulation. Plant developmental defects that were caused by high levels of NO included delayed flowering time, retarded root growth and reduced starch granule formation. These phenotypic defects could be mediated by sucrose supplementation, suggesting an essential role of NO-sugar cross-talks in plant growth and development. Our findings suggest that molecular manipulations could be used to improve fruit and vegetable sweetness.

Evaluation of the Hair Cell Regeneration in Zebrafish Larvae by Measuring and Quantifying the Startle Responses.

The zebrafish has become an established model organism for the study of hearing and balance systems in the past two decades. The classical approach to examine hair cells is to use dye to conduct selective staining, which shows the number and morphology of hair cells but does not reveal their function. Startle response is a behavior closely related to the auditory function of hair cells; therefore it can be used to measure the function of hair cells. In this study, we developed a device to measure the startle response of zebrafish larvae. By applying various levels of stimulus, it showed that the system can discern a 10 dB difference. The hair cell in zebrafish can regenerate after damage due to noise exposure or drug treatment. With this device, we measured the startle response of zebrafish larvae during and after drug treatment. The results show a similar trend to the classical hair cell staining method. The startle response was reduced with drug treatment and recovered after removal of the drug. Together it demonstrated the capability of this behavioral assay in evaluating the hair cell functions of fish larvae and its potential as a high-throughput screening tool for auditory-related gene and drug discovery.

Betacyanins from Portulaca oleracea L. ameliorate cognition deficits and attenuate oxidative damage induced by D-galactose in the brains of senescent mice.

This experiment was designed to assess the protective effect of betacyanins from Portulaca oleracea L. against the D-galactose (D-gal)-induced neurotoxicity in mice. Betacyanins from Portulaca oleracea markedly reversed the D-gal-induced learning and memory impairments, as measured by behavioral tests. The activities of superoxide dismutases (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) in D-gal-treated mice were enhanced, while the content of the lipid peroxidation product malondialdehyde (MDA) was decreased by betacyanin administration. Furthermore, significant negative correlations were found between mouse latency in finding the platform and the activities of SOD, CAT GR and GPx in the mouse brain, but the level of MDA correlated positively with the latency. These results suggest that the neuroprotective effect of betacyanins against D-gal-induced neurotoxicity might be caused, at least in part, by an increase in the activities of antioxidant enzymes with a reduction in lipid peroxidation. In comparison with vitamin C (VC), the betacyanins had a more pronounced effect on ameliorating cognition deficits in mice.

[Effect of different N, P and K fertilizers on soil pH and available Cd under waterlogged conditions].

In order to tackle the problem of Cd pollution in paddy soils and investigate soil available Cd as affected by different fertilizers, incubation experiments were carried out to study the effects of different N, P and K fertilizers and pH by adding acid or base on soil available Cd under waterlogged conditions. Results revealed that soil pH increased sharply after the soil was flooded, especially at the beginning of incubation, and gradually decreased with incubation time and finally tended to approach the neutral values. The patterns of soil pH change were just opposite to those of soil available Cd, a negative correlation observed between the two. Soil flooding made the soil available Cd drop by 58.2%-84.1%. There were significant differences between different fertilizer types/varieties on soil available Cd, being most complex with N fertilizers and followed by K and P fertilizers. Among the fertilizers studied, ammonium chloride showed the unique ability in reducing soil pH and enhancing soil available Cd, and urea, single super phosphate and potassium chloride also promoted to a less extent amounts of Cd extracted from the soil. Ammonium sulfate, potassium sulfate and mono-ammonium phosphate significantly decreased soil available Cd compared to the CK treatment. Whether or not the soil was flooded, soil available Cd was highly negatively correlated with soil pH after adding acid or base (R = - 0.994 without incubation and R = - 0.919 after incubation for 60 d). The results further suggest that in the Cd polluted paddy soil, use of ammonium chloride should be avoided, S bearing fertilizers in combination with alkaline materials can be adopted, and the rice field should be flooded all the time during growing season, all the these practices can effectively lower soil available Cd.