Effects of Environmental and Spatial Variables on Bacteria in Zhanjiang Mangrove Sediments.

The bottom mud of mangroves contains numerous microbial groups that play an important role in the main ecological functions of the mangrove ecosystem. The diversity and functional and environmental factors related to microbial communities, in terms of the assembly process and in environmental adaptation of the abundance and rare bacterial communities in the mangrove ecosystem, have not been fully explored. We used 16S high-throughput sequencing and operational taxonomic unit analysis to compare the diversity and composition of bacterial communities in different tidal zones in the sediments of the Zhanjiang Gaoqiao Mangrove Nature Reserve, compare the ecological adaptation thresholds and phylogenetic signals of bacterial communities under different environmental gradients, and examine the factors affecting the composition of the bacterial community. The diversity of microbial species and structure and function of the mangrove sediments were affected by the environment, showing the trend: mid tide zone > climax zone > low tide zone. Organic matter content, oxygen content, pH, and total phosphorus were identified as important environmental factors determining the functional diversity of bacterial communities and survival, while pH influences species evolution. The abundant taxa showed a wider response threshold and stronger phylogenetic signals of ecological preference across environmental gradients compared to rare taxa. The abundant bacterial groups have broader environmental adaptability than rare bacterial groups, and different environmental factors affect different communities and functions in the mangrove ecological environment. These results elucidate the mechanism underlying the generation and maintenance of bacterial diversity in response to global environmental changes.

The oral bioavailability, excretion and cytochrome P450 inhibition properties of epiberberine: an in vivo and in vitro evaluation.

Epiberberine (EPI) is a novel and potentially effective therapeutic and preventive agent for diabetes and cardiovascular disease. To evaluate its potential value for drug development, a specific, sensitive and robust high-performance liquid chromatography-tandem mass spectrometry assay for the determination of EPI in rat biological samples was established. This assay was used to study the pharmacokinetics, bioavailability and excretion of EPI in rats after oral administration. In addition, a cocktail method was used to compare the inhibition characteristics of EPI on cytochrome P450 (CYP450) isoforms in human liver microsomes (HLMs) and rat liver microsomes (RLMs). The results demonstrated that EPI was rapidly absorbed and metabolized after oral administration (10, 54 or 81 mg/kg) in rats, with Tmax of 0.37-0.42 h and T1/2 of 0.49-2.73 h. The Cmax and area under the curve values for EPI increased proportionally with the dose, and the oral absolute bioavailability was 14.46%. EPI was excreted mainly in bile and feces, and after its oral administration to rats, EPI was eliminated predominantly by the kidneys. A comparison of the current half-maximal inhibitory concentration and Ki values revealed that EPI demonstrated an obvious inhibitory effect on CYP2C9 and CYP2D6. Furthermore, its effect was stronger in HLM than in RLM, more likely to be a result of noncompetitive inhibition.

Pharmacodynamic study on insomnia-curing effects of Shuangxia Decoction in Drosophila melanogaster.

The present study aimed to establish a pharmacodynamic method using the pySolo software to explore the influence of freeze-dried powders of Shuangxia Decoction (SXD) on the sleep of normal Drosophila melanogaster and the Drosophila melanogaster whose sleep was divested by light. The dose-effect and the time-effect relationships of SXD on sleep were examined. The effect-onset concentration of SXD was 0.25%, the plateau appeared at the concentration of 2.5% and the total sleep time showed a downtrend when the concentration was greater than 2.5%. The sleep time was the longest on the fourth day after SXD was given. The fruit fly sleep deprivation model was repeated by light stimulation at night. The middle dosage group (2.5%) had the best insomnia-curing effect. In conclusion, using the pySolo software, an approach for the pharmacodynamics study was established with Drosophila melanogaster as a model organism to determine the insomnia-curing effects of the traditional Chinese medicine (TCM). Our results demonstrated the reliability of this method. The freeze-dried powders of SXD could effectively improve the sleep quality of Drosophila melanogaster.

[Nondestructive recognization of mountain cultivated ginseng and garden cultivated ginseng by FTIR microspectroscopy].

Fourier transform infrared (FTIR) microspectroscopy technology is the combination of the FTIR spectrometer and the microscope. This technology is of simple preparation of the samples, can be used in micro-area analysis and micro-samples, and reflect the nature of the samples spectra. Panax ginseng include mountain cultivated ginseng (MCG), garden cultivated ginseng (GCG) and mountain wild ginseng (MWG), but the excavation of MWG is prohibited in China. So, only MCG and GCG were collected and recorded in Chinese pharmacopoeia. In this study, we developed a discriminant analysis (DA) method for recognition of MCG and GCG using FTIR microspectroscopy technology. Twenty MCG samples and twenty four GCG samples were obtained, and their spectra of IR microspectroscopy were collected. Then 33 samples were randomly selected into calibration set and the remaining 11 of the samples were selected into validation set. The authors optimized the pretreatment method, the principal components, the modeling region and the scanning parts when developing the models. The optimized model of discriminant analysis was developed using the pretreatment multiplicative scatter correction (MSC) + Savitzky-Golay filter (SG) smoothing, the region 3 932.14-669.18 cm(-1), 4 principal components and the rhizome part. The accuracy of the optimized model got up to 100%. The result demonstrated that infrared microspectroscopy technology combined with DA is of simple operation, rapid, nondestructive and effective, and can be applied to recognize MCG and GCG.

[Comparative study on quality of Tongrentang red ginseng and Korean red ginseng--determination of ginsenosides and polysaccharides].

OBJECTIVE: To establish methods for quantitative determination of ginseng saponins, ginsenoside Rg1, Re, Rb1 and polysaccarides and compare the qualities of Tongrentang Red Ginseng and Korean Red Ginseng. METHOD: Macroreticular resin-colorimetric method was developed to determine ginseng saponins and a new HPLC method with gradient eluents was established for determination of ginsenoside Rg1, Re, Rb1. For ginseng polysaccharides, phenol-oil of vitriol colorimetric method was developed and some factors were also optimized. RESULT: The content of ginseng saponins in Tongrentang Red Ginseng was not lower than that of Korean Red Ginseng. Ginsenoside Rg1 and Rb1 in Tongrentang Red Ginseng were higher than those in Korean Red Ginseng, while Ginsenoside Re was slightly lower than that of Korean Red Ginseng. However, the amount of Ginseng Polysaccharides in Tongrentang Red Ginseng was greater than those in Korean Red Ginseng. CONCLUSION: The contents of ginseng saponins and ginsenoside Rg1, Re, Rb1 in Tongrentang Red Ginseng were not lower than that in Korean Red Ginseng. The methods for determination of ginsenosides and ginseng polysaccharides were quite accurate and reliable to the quality control of Ginseng.