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To explore the mechanisms of Buyang Huanwu Decoction (BYHWD) modulating the gut microbiome and trimethylamine oxide (TAMO) to exert cardioprotective effects.Ligation of the left anterior descending coronary artery was performed in rats to induce heart failure (HF). Except for the sham-operation group (n=10), 36 operation-induced models were randomized into 3 groups using a random number table (n=12 in each group): the model group, the BYHWD group (15.02 g/kg BYHWD), and the positive group (4.99 g/kg metoprolol succinate). After 4-week treatment (once daily by gavage), echocardiography was applied to evaluate the cardiac function and the Tei index (the ratio of ventricular isovolumic contraction time (IVCT) and isovolumic diastolic time (IVRT) to ejection time (ET)) was calculated; hematoxylin-eosin (HE) staining was observed to characterize the pathology of the myocardium and small intestinal villi. D-lactic acid was detected by an enzyme-linked immunosorbent assay (ELISA). Expressions of occludin, claudin-1, and zonula occludens (ZO-1) were detected by Western blot. 16S ribosomal ribonucleic acid (16S rRNA) sequencing was used to explore the changes in the intestinal flora. TMAO was detected via liquid chromatography-tandem mass spectrometry (LC-MS/MS).In the echocardiography, the Tei index was considerably lower in the positive and BYHWD groups compared with the model group (P0.05). Besides, BYHWD improved the pathology of myocardium and small intestine of HF rats and lowered the D-lactic acid content in the serum, when compared with the model group (P0.05). BYHWD also improved the expression of occludin and claudin-1 (P0.05); in the gut microbiota analysis, BYHWD slowed down modifications in the structure distribution of gut microbiota and regulated the diversity of intestinal flora in HF rats. The content of TMAO in the serum was significantly lowered by BYWHT compared with the model group (P0.05).BYHWD may delay progression of HF by enhancing the intestinal barrier structure, and regulating intestinal flora and TAMO.

Five novel bisindole alkaloids, hunzeylanines A-E (1-5), with an unprecedented skeleton were isolated from the roots of Hunteria zeylanica. Compounds 1-5 represent the first examples of akuammine-pleioarpamine-type bisindole alkaloids fused with a dihydropyran unit. Their structures including absolute configurations were established through comprehensive spectroscopic data analyses and computational calculation methods. The plausible biogenetic pathway of 1 was also proposed. Alkaloids 1 and 2 displayed moderate cytotoxicity toward three human cancer cell lines (MDA-MB-231, AV3, and Huh7).

Six new structurally diverse indole alkaloids, melohemsines J-M (1-4), 11-hydroxy-Δ14-vincamine (5), and 11-hydroxy-16-epi-Δ14-vincamine (6), and 15 known alkaloids were isolated from the leaves and twigs of Melodinus hemsleyanus Diels. These new compounds and their absolute configurations were determined through spectroscopic data analyses, X-ray diffraction, and computational methods. Melohemsine J (1) is the first example of a melodinus-type alkaloid possessing a 6/6/5/5/6/5 hexacyclic skeleton and containing a tetrahydrofuro[2,3-b]pyridine-2(3H)-one unit. Melohemsine K (2) is an unusual aspidosperma-type alkaloid possessing a 6/5/6/5/5 pentacyclic architecture with a contracted E ring (loss of CH2). Compounds 5-10 and 16 exhibited vasorelaxant activities with EC50 values of 0.8-3.8 μM. In addition, compound 4 displayed moderate cytotoxicity toward the tumor cell lines HepG2 and A-549 with EC50 values of 18.7 and 28.7 μM, respectively.

Three new monoterpenoid indole alkaloids (MIAs), hunterines A-C (1-3), were isolated from Hunteria zeylanica. Compound 1 possesses a unique skeleton with an unprecedented azabicyclo[4.3.1]decane ring system. Compounds 2 and 3 are a pair of epimeric vobasinylindole alkaloid heterodimers. Their structures including absolute configurations were established by spectroscopic analyses, X-ray diffraction, computational calculation, and the modified Mosher's method. Plausible biogenetic pathways of 1-3 were also proposed. Alkaloid 1 showed moderate cytotoxic activity against the HepG2 cell line.

This study demonstrated a novel process configuration for sustaining mainstream anammox by integrating the anammox and endogenous partial denitrification-and-phosphorus removal (EPDPR) in two-stage sequencing batch reactors (SBRs). In the EPDPR-SBR, high nitrate-to-nitrite transformation (68.2%) and P removal (99.3%) were achieved by adjusting the anaerobic/anoxic/aerobic durations and influent nitrate concentration, providing a suitable NO2−-N/NH4+-N (∼1.37) for subsequent anammox reaction. In the Anammox-SBR, ∼95% of TN was removed without external carbon and oxygen demands. Satisfactory effluent quality (∼6 mgTN/L and 0.2 mgP/L) achieved in the integrated EPDPR/anammox opens a new window towards the energy-efficient wastewater treatment. Microbial analysis further revealed that Dechloromonas (1.6–9.6%) and Candidatus Competibacter (6.4–5.8%) respectively conducted P removal and NO2−-N production (79.2%) from NO3−-N denitrification in the EPDPR-SBR, whereas Candidatus Kuenenia (7.0–29.7%) dominated NO2−-N and NH4+-N removal (91.3% and 99.5%) in the Anammox-SBR, with 10 genera identified as denitrifying bacteria (0.6–8.1%) further reduced 18.9% of the produced NO3−-N.

In this study, a novel process was developed by combining endogenous partial denitrification (EPD, NO3−-N → NO2−-N) with denitrifying phosphorus removal (DPR) in an anaerobic/anoxic/aerobic sequencing batch reactor (SBR) to achieve a stable nitrite accumulation and phosphorus removal from high-strength nitrate (NO3−-N: 186.5 mg/L) and municipal wastewater (NH4+-N: 52.6 mg/L, chemical oxygen demand (COD): 242.7 mg/L). After 138-day, high nitrate-to-nitrite transformation ratio (NTR) of 75.3% and PO43−-P removal efficiency of 92.3% were achieved by controlling the anaerobic drainage ratio and anoxic/aerobic durations. During the anaerobic stage (2.5 h), carbon source in raw municipal wastewater was efficiently utilized by phosphorus-and-glycogen accumulating organisms (PAOs and GAOs) to enhance intracellular carbon storage (69.9% in anaerobic COD consumption), providing sufficient carbons for subsequent anoxic EPD and DPR. During the anoxic stage (2.5 h), high activity of DGAONO3-NO2 (denitrifying GAOs conducting NO3−-N → NO2−-N) over DPAONO3 and DGAONO3 (DPAOs and DGAOs conducting NO3−-N → N2) in nitrate denitrification (77.7% > 8.2% and 5.7%) facilitated the nitrite accumulation and phosphorus uptake. In the last short aerobic stage (10 min), further phosphorus was removed by aerobic PAOs without initiating ammonia/nitrite oxidation. Thus, effluent NO2−-N/NH4+-N ratio of 1.02:1 (close to the theoretical value of 1.32:1 for anammox process) with limited NO3−-N, PO43−-P and COD (1.8, 0.4 and 23.5 mg/L, respectively) were obtained. This provides the potential for advanced nutrient removal from nitrate and municipal wastewaters by combining EPDPR with anammox. Microbial community analysis revealed that Cluster I of Defluviicoccus-GAO group (∼7%) dominated the high nitrite accumulation performance, while Accumulibacter-PAO group (15 ± 3%) was responsible for the P removal performance.

Five novel bisindole alkaloids, hunzeylanines A-E (

Six new structurally diverse indole alkaloids, melohemsines J-M (

In this study, a novel process combining partial denitrification (PD, NO

Three new monoterpenoid indole alkaloids (MIAs), hunterines A-C (

An anaerobic (180 min)/aerobic operated sequencing batch reactor (SBR) fed with urban sewage was optimized by regulating the aeration quantity to investigate the deep-level nitrogen (N) and phosphorus (P) removal. The amount of aeration was regulated by adjusting the volume of gas per unit volume of reactor passed in unit time, when the unit is L·(min·L)

This study focuses on the nitrogen (N) and phosphorus (P) removal characteristics in a simultaneous nitrification endogenous denitrification and phosphorus removal (SNEDPR) system operating at different sludge retention time (SRT). Four extended anaerobic/low aerobic (dissolved oxygen:0.5-1.0 mg·L

This study focuses on the investigation of the nitrogen (N) and phosphorus (P) removal characteristics of a combination of enhanced phosphorus removal (EBPR) with simultaneous partial nitrification endogenous denitrification (SPND) and post-partial denitrification process. An anaerobic/aerobic/anoxic (A/O/A) operated sequencing batch reactor (SBR) fed with urban sewage was optimized by regulating the aeration rate and anoxic time. Based on this optimization, deep-level nitrogen and phosphorus removals from low C/N urban sewage could be realized. The experimental results show that the effluent PO

This study focuses on the nitrogen (N) and phosphorus (P) removal characteristics in a simultaneous nitrification-endogenous denitrification and phosphorus removal (SNEDPR) system at different influent C/P ratios. An extended anaerobic/low aerobic (dissolved oxygen:0.5-1.0 mg·L

This study focused on the nitrogen (N) and phosphorus (P) removal performance optimization of simultaneous partial nitrification-endogenous denitrification and phosphorus removal (SPNDPR) systems. An anaerobic (180 min)/aerobic operated sequencing batch reactor (SBR) fed with domestic wastewater was used for investigating the startup and optimization of SPNDPR by regulating the aeration rate and aerobic duration time. The experimental results showed that at an aerobic aeration rate of 0.8 L·min

In order to realize the simultaneous treatment of low C/N municipal wastewater and high nitrate wastewater, a sequencing batch reactor (SBR), inoculated with activated sludge, was used to initiate the denitrifying phosphorus removal coupled with simultaneous nitrification and endogenous denitrification (DPR-SNED). The anaerobic/anoxic/hypoxic durations and dissolved oxygen (DO) concentration were appropriately controlled, and the nitrogen and phosphorus removal characteristics were examined. The experimental results demonstrated that, in the anaerobic/hypoxia operation mode, with an anaerobic duration of 3 h and DO concentration of 0.5-1.0 mg·L

Post-endogenous denitrification (PED) process, utilizing internal rather than external carbons, has been proposed for nitrogen removal from wastewaters. However, its potential nitrogen removal capacity has not been approached, especially when facing simultaneous phosphorus removal. Here, the nitrogen removal ability of PED was further investigated by treating municipal and high-nitrate wastewaters in a novel process combined with synchronous nitritation, denitrification and phosphorus removal (SNiDPR). After optimization, the anoxic specific nitrite (and nitrate) reduction rate was increased from 0.41 to 1.13 mgN gVSS-1 h-1, accompanied with PED efficiency raising from 16.8% to 80.9%. It ensured that, by utilizing the limited organic carbons in municipal wastewater, deep-level nutrient removal could still be achieved (total nitrogen and phosphorus removal efficiencies were 93.1% and 99.9%, respectively). Nitrospira (0.1-0.4%) was outcompeted by Nitrosomonas (4.7-3.3%), which contributed to accumulation of nitrite in aerobic stage (99.6%) and dramatically reduced the carbons demand of following PED. Enriched Dechloromonas (8.5-5.6%) and Candidatus_Competibacter (9.1-11.3%) might play key roles in sufficient utilization of organic carbons in municipal wastewater anaerobically, and respectively facilitate aerobic phosphorus removal (100%) and anoxic PED (60.7% of overall nitrogen removal).