Nutrient removal, methane and nitrous oxide emissions in a hybrid constructed wetland treating anaerobic digestate.

A pilot hybrid constructed wetland (CW) planted with reeds (Phragmite australis) and rice (Oryza sativa L.) was designed to treat liquid anaerobic digestate in the Yangtze River Delta, China. The hybrid CW system was composed of four stages: two reed vegetated vertical subsurface flow beds (VSSF: U1 and U2) in sequence, followed by a reed vegetated horizontal subsurface flow bed (HSSF: U3) and a rice vegetated surface flow bed (SF: U4). The average loading rate of digestate was 3.6 m3 per day during the experimental period. The average concentrations of TN and TP in the influent were 379 ± 58 mg L-1 and 29.6 ± 9.2 mg L-1, while the average removal efficiencies of TN and TP were 94.6% and 88.4%. Both TN and TP removal efficiencies in the second VSSF containing zeolite gave the highest removal performance, in which the mass removal rates were 21.3 ± 8.0 g-N m-2 d-1 and 0.99 ± 0.69 g-P m-2 d-1, respectively. Similarly, the highest removal performance for COD was also observed in the second VSSF with a mass removal rate of 79.9 ± 72.4 g-COD m-2 d-1. On the other hand, the average CH4 and N2O fluxes were highest in the first VSSF, at 31.8 ± 12.9 mg m-2 h-1 and 3.7 ± 2.8 mg m-2 h-1, respectively. There was a significant linear relationship between CH4 flux and DOC concentration in the pore water as well as a correlation between N2O flux and TN concentration. Total GWP of the hybrid CWs, derived from CH4 and N2O emissions, was 792.4 kg CO2-eq, of which CH4 and N2O emissions accounted for 66.0% and 34.0%, respectively. Consequently, the hybrid CWs emitted on average 0.93 kg CO2-eq to remove 1 kg COD while the average EF of TNin was 0.34%, suggesting that the use of multistage hybrid CWs could be efficiency-wise and environmentally a promising strategy for anaerobic digestate treatment.

Straw biochar hastens organic matter degradation and produces nutrient-rich compost.

Biochar derived from wheat straw was added to pig manure in amounts equivalent to 5%, 10%, or 15% (w/w, wet weight). The ratios of NH4(+)/NO3(-) and of UV light absorption at a wavelength of 254nm (SUV254) and dissolved organic carbon (DOC) indicated that compost with 10-15% biochar became more mature and more humified within 42days of composting, and the content of DOC and the concentration of NH4(+) in such compost decreased by 37.5-62.0% and 4.0-20.9%, respectively, compared to the corresponding levels in the control. Addition of biochar lowered the pH and increased electrical conductivity by 7.0-37.5% compared to the control and also increased the concentrations of water-soluble nutrients including PO4(3-) (5.6-7.4%), K(+) (14.2-58.6%), and Ca(2+) (0-12.5%). It is therefore recommended that straw biochar be added to pig manure at 10-15% by weight.

Oxygen vectors used for S-adenosylmethionine production in recombinant Pichia pastoris with sorbitol as supplemental carbon source.

In order to increase the yield of S-adenosylmethionine (SAM) in recombinant Pichia pastoris, a strategy of adding oxygen vectors and supplemental carbon sources was described. Three organic solutions were used as oxygen vectors for SAM accumulation at different concentrations and addition times. Firstly, n-hexane (0.5%) or n-heptane (1.0%) was added after 72 h of cultivation to improve SAM production. Carbon metabolism was scarce during the induction phase because of low methanol concentration. Secondly, sorbitol (1.2%), selected from three candidates (glycerol, lactic acid, and sorbitol), was used as the supplemental carbon source. The yield of SAM was improved significantly (53.26%) at 1.0%n-heptane added at 72 h (48 h induction), 1.2% sorbitol added at 72, 96, and 120 h of cultivation and 1.0% methanol added every 24 h during cultivation.

[Regulatory effect of ligustrazine and Radix astragalus on RANTES and receptor CCR5 expression in the genesis and development process of endometriosis].

OBJECTIVE: To investigate the regulatory effect of ligustrazine and Radix Astragalus (Chinese drugs for supplementing qi and activating blood circulation) on uterine mucosa stromal cyto-chemotactic factor RANTES and receptor CCR5 expression. METHODS: The eutopic and ectopic endometrial stromal cells (EMSC) isolated and purified from 10 patients with ovarian endometrial cyst were selected as the experimental group, while those from 10 patients with benign lesion were selected as the control group. After they were intervened by different factors, including astragalus injection (AI), ligustrazine injection (LI), AI + LI, and Danazol, the expression levels of RANTES and CCR5 in the cells were detected by ELISA and RT-PCR. RESULTS: RANTES expressions in eutopic and ectopic EMSC were different insignificantly (P > 0.05). The ectopic EMSC RANTES expression was 13.602 +/- 3.358 ng/L and eutopic EMSC RANTES was 12.850 +/- 7.997 ng/L in the positive control group, which was significantly higher than that in the negative control group (both being 0.027 +/- 0.016 ng/L, P <0.05), and the ectopic EMSC expressions after intervened with Chinese drugs were significantly lower than that in the positive control group (P <0.05). CCR5 expression in ectopic EMSC was 0.759 +/- 0.039 ng/L, which was higher than that in eutopic EMSC (0.249 +/- 0.026 ng/L, P <0.05). Ectopic EMSC CCR5 expression was higher in the positive control group than that in the negative control group (0.759 +/- 0.039 ng/L vs 0.478 +/- 0.094 ng/L, P <0.05). Similar situation also was shown between the positive and negative control groups in terms of eutopic EMSC CCR5 expression (0.249 +/- 0.026 ng/L vs 0.131 +/- 0.021 ng/L, P < 0.01), and the expression was significantly lower in all the Chinese drugs treated EMSC groups as compared with that in the positive control group (P < 0.01). CONCLUSION: CCR5 expression was higher in ectopic EMSC than that in eutopic EMSC. Ligustrazine and Radix Astragalus could down-regulate the auto-secretion of RANTES and CCR5 in patients with endometriosis.