[Correlation of Allelopathy of Rehmannia glutinosa Root Exudates and Their Phenolic Acids Contents].

OBJECTIVE: To study the allelopathic potential of Rehmannia glutinosa root exudates in different growth stages and dynamic change of phenolic acids contents, in order to reveal the correlation between phenolic acids and allelbpathy effect of Rehmannia glutinosa. METHODS: Root exudates of Rehmannia glutinosa in different growth stages were obtained by a new instrument which was used to collect the root exudates of xerophytes. After that, bioassay was applied to estimate allelopathy effect of the root exudates. HPLC was used to determine the contents of five phenolic acids (coumaric acid, 4-hydroxybenzoic acid, vanillic acid, syringic acid and ferulic acid) which were reported to relate to allelopathy effect. Correlation of bioassay data and HPLC data were also analyzed. RESULTS: The germination rate of radish after soaking by root exudates of different growth stages of Rehmannia glutinosa was 97. 89%, 92. 38%, 89. 52%, 85. 71%, 85. 71%, 84. 76% and 83. 81%, respectively, which indicated a decline trend. And significant differences were shown from previous enlargement stage compared with the contrast. The bud length after soaking by root exudates was 5. 68, 5. 76, 5. 91, 5. 65, 5. 41, 5. 28 and 5. 11 cm, separately, which increased slightly before decreasing gradually. Previous enlargement stage was also the initial period when significant differences were shown. Five phenolic acids were detected in root exudates by HPLC, while the change of their contents and the allelopathy effect of root exudates did not perform a similar trend. Correlation analysis indicated the five phenolic acids did not have significant relevance (r = - 0. 666 - 0. 590) with germination rate and bud length of radish except the negative correlation (r = -0. 833, P <0. 05) of syringic acid and bud length. CONCLUSION: Significant allelopathy effect of Rehmannia glutinosa is performed from previous enlargement stage and enhanced with its growth. Syringic acid is a probable dominant allelochemical of Rehmannia glutinosa.

[Effect of substrate of edible mushroom on continuously cropping obstacle of Rehmannia glutinosa].

The continuous cultivation of Rehmannia glutinosa causes the accumulation of phenolic acids in soil. It is supposed to be the reason of the so called "continuously cropping obstacle". In this study, phenolic acids (hydroxybenzoic acid, vanillic acid, eugenol, vanillin and ferulic acid) were degraded by the extracta of all the tested spent mushroom substrate (SMS) and the maximal degradation rate was 75.3%, contributed by extraction of SMS of Pleurotus eryngii. Pot experiment indicated that hydroxybenzoic acid and vanillin in soil were also degraded effectively by SMS of P. eryngii. The employment of SMS enhanced ecophysiology index to near the normal levels, such as crown width, leaves number, leaf length, leaf width and height. At the same time, the fresh and dry weight and total catalpol concentration of tuberous root weight of R. glutinosa was increased to 2.70, 3.66, 2.25 times by employment of SMS, respectively. The increase of bacteria, fungi and actinomycetes numbers in rhizosphere soil were observed after the employment of SMS by microbial counts. The employment of SMS also enhanced the enzyme activity in soils, such as sucrase, cellulase, phosphalase, urease and catelase. These results indicated that the employment of SMS alleviated the continuously cropping obstacle of R. glutinosa in some extent.

[Interactive effect of spent mushroom compost and rhamnolipids to enhance the efficiency of alfalfa remediation of aged PAHs contaminated soil].

Polycyclic aromatic hydrocarbons (PAHs) are a group of the most widespread organic pollutants, which distributed widely in soil and sediment. Pot experiment was conducted to improve efficiency of phytoremediation using alfalfa (Medicago sativa L.) in aged PAHs contaminated soil by introducing spent mushroom compost and rhamnolipids. Plant biomass, PAHs concentrations, number of soil microorganism, soil enzyme activity and soil microbial functional diversity were determined after 60 days of alfalfa growth. The results showed that within 60 days, removal ratio of PAHs in treatment of alfalfa alone (AL) reached to 14.43%, while removal ratio of PAHs in treatments of "GZ + RH0.5, + AL" and "GZ + RH1.0 + AL" reached to 32.64% and 36.95%, which were 115.45% and 156.06% higher than that of phytoremediation. Contrasted to the control, the treatment of "GZ + RH1.0 + AL" had more plant biomass than others, shoot and root dry weight were 1.05 g/pot and 0.20 g/pot, respectively. During the process of phytoremediation, the number of soil bacteria and fungi were greatly increased by "GZ + RH1.0 + AL" and reached to 31.37 x 10(6) CFU x g(-1) and 5.86 x 10(6) CFU x g(-1), especially the number of PAHs-degrading bacteria reached to 39.57 x 10(5) MPN x g(-1), which were 29 times more than control treatment and 4 times more than treatment of alfalfa alone (AL). Moreover, soil dehydrogenase activity and the functional diversity of soil microbial community were increased significantly by the treatment of "GZ + RH1.0 + AL", respectively. Therefore, interaction of spent mushroom compost and rhamnolipids to enhance the phytoremediation efficiency had satisfied results in removal aged PAHs from an agricultural soil, the feasibility of this method needed to be further proved by large-area scale field experiment.

[Interaction of biosurfactant-microorganism to enhance phytoremediation of aged polycyclic aromatic hydrocarbons (PAHS) contaminated soils with alfalfa (Medicago sativa L.)].

A pot experiment in greenhouse was carried out to investigate the interactive effect of rhamnolipids (RH) addition and PAHs-specific degrading bacteria (DB) inoculation on the phytoremediation efficiency for removal polycyclic aromatic hydrocarbons (PAHs) from agricultural soils. Results indicated that RH addition and DB inoculation promoted alfalfa (Medicago sativa L. ) growth and PAHs degradation in the soil. After 90 days, residual PAHs concentration in soil reduced 30.0% and 49.6% for the treatment of RH and DB, respectively, but only 21.7% for control. For the treatment of RH + DB, residual PAHs concentration in soil reduced 53.9%, showing synergy effect of RH addition and DB inoculation. In addition, the average PAHs degradation gradually reduced with the increase of the PAHs rings, but DB inoculation promoted the degradation of four-ring PAHs and five-ring PAHs. The number of PAHs degrading bacteria and dehydrogenase activity increased with the removal ratio of PAHs. Therefore RH addition and PAHs-specific degrading bacteria inoculation were effective in enhancing the phytoremediation efficiency of the long-term PAHs contaminated soils.

The study of matrix metalloproteinase-9 and tumor necrosis factor-or in predicting chorioamnhionitis in patients with premature rupture of membranes / 中国基层医药

Objective To study the relation of matrix metalloproteinase-9 in serum and tumor necrosis fac- tor-?in serum and amniotic fluid in predicting ehorioamnhionitis in patients with premature rupture of membranes (PROM).Methods The levels of MMP-9 in serum and TNF-?in serum and amniotie fluid were measured by ra- dioimmunoassay and ELISA in 67 cases with premature rupture of membranes as study group and 40 cases normal full-termed pregnant women as controls group.Results(1)The levels of TNF-?in amniotie fluid and MMP-9 in serum in study group were significantly higher than those in controls group(P0.05).(2)In study group,the levels of MMP-9 of serum in0.05).Conclusions The levels of TNF-?in amniotic fluid and MMP-9 in serum were valuable clinical indices for identification of chorioamnionitis in patients with PROM.The levels of MMP-9 in serum also could assess the time of rupture of membranes and the degree of ehorioamnionitis.