ABSTRACT
Anaerobic ammonium oxidation has been considered as an environmental-friendly and energy-efficient biological nitrogen removal (BNR) technology. Recently, new reaction pathway for ammonium oxidation under anaerobic condition had been discovered. In addition to nitrite, iron trivalent, sulfate, manganese and electrons from electrode might be potential electron acceptors for ammonium oxidation, which can be coupled to traditional BNR process for wastewater treatment. In this paper, the pathway and mechanism for ammonium oxidation with various electron acceptors under anaerobic condition is studied comprehensively, and the research progress of potentially functional microbes is summarized. The potential application of various electron acceptors for ammonium oxidation in wastewater is addressed, and the N2O emission during nitrogen removal is also discussed, which was important greenhouse gas for global climate change. The problems remained unclear for ammonium oxidation by multi-electron acceptors and potential interactions are also discussed in this review.
Subject(s)
Oxidation-Reduction , Wastewater , Wastewater/chemistry , Waste Disposal, Fluid/methods , Electrons , Anaerobiosis , Ammonium Compounds/chemistry , Water Purification/methods , Quaternary Ammonium Compounds/chemistryABSTRACT
One rare flavonoid-diterpene heterodimer, denticulatain C (1), one modified geranyl-type side chain substituted flavonoid, denticulatain D (2) and one geranylated flavonoid, denticulatain E (3), as well as 11 known compounds (4-14) were isolated from the fronds of Macaranga denticulata. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 4 and 8 inhibited the proliferation of A-549 cell line with IC50 values of 48.6 and 20.2 µg/mL, respectively. Compounds 3, 6, and 8 exhibited significant antiangiogenic activity on a zebrafish model with IC50 values of 9.78, 0.34, and 2.55 µg/mL, respectively.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Euphorbiaceae/chemistry , Flavonoids/pharmacology , Angiogenesis Inhibitors/pharmacology , Animals , Cell Line, Tumor , Diterpenes/pharmacology , Drug Screening Assays, Antitumor , Humans , Inhibitory Concentration 50 , Molecular Structure , Plant Extracts/chemistry , Plant Leaves/chemistry , Prenylation , ZebrafishABSTRACT
Three new diterpenoids, stracheyioids A-C (1-3), as well as 36 known compounds (4-39) were isolated from the whole plants of Euphorbia stracheyi. Compound 1 was a rare 13-deoxy tigliane diterpenoid and compound 2 was an ingenol diterpenoid characterized by an unique 2Z,4Z-decadienoyl acidic moieties. All the known compounds were isolated from E. stracheyi for the first time. Their structures were elucidated on the basis of extensive spectroscopic interpretation. Compounds 1-39 were tested for their cytotoxicity against five cancer cell lines (A-549, MCF-7, Hep G2, Hela and P388) and showed IC50 values in the range 6.64-42.86 µM. The antiangiogenic activities of the isolated compounds were also evaluated using a zebrafish model.
Subject(s)
Angiogenesis Inhibitors/isolation & purification , Euphorbia/chemistry , Terpenes/isolation & purification , Angiogenesis Inhibitors/chemistry , Animals , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Terpenes/chemistry , ZebrafishABSTRACT
Four new jatropholane-type diterpenes (1-4), named sikkimenoids A-D, were isolated from the aerial parts of Euphorbia sikkimensis. The structural elucidations of 1-4 were accomplished by extensive NMR analyses, and their absolute configurations were established by ECD calculations. Compound 2 exhibited weak antiangiogenic activity with an IC(50) value of 43.0 µM when evaluated using a zebrafish model.
Subject(s)
Angiogenesis Inhibitors/isolation & purification , Diterpenes/isolation & purification , Drugs, Chinese Herbal/isolation & purification , Euphorbia/chemistry , Algorithms , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacology , Animals , Disease Models, Animal , Diterpenes/chemistry , Diterpenes/pharmacology , Drug Screening Assays, Antitumor , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Humans , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , ZebrafishABSTRACT
OBJECTIVE: To study the chemical constituents of Gastrodia elata. METHODS: The compounds were isolated by silica gel column chromatography and recrystallization and their structures were elucidated by spectral analysis. RESULTS: The structures of 14 compounds were identified as: p-hydroxybenzyl alcohol (1), p-hydroxybenzaldehyde (2), 3, 4-dihydroxybenzaldehyde (3), 4, 4'-dihydroxy, dibenzyl ether (4), 4-hydroxymethyl benzyl-4'-hydroxy-3'-(4"-hydroxy benzl) benzyl ether (5), 4-ethoxybenzyl alcohol (6), anisic alcohol (7), bis(3, 4-dihydroxyphenyl) methane (8), 4, 4'-dihydroxydiphenyl methane (9), 2, 4-bis(4'-hydroxy-benzyl)-phenol (10), 4-( methoxymenthyl) benzene-1, 2-diol (11), p-methylphenyl-1 -O-beta-D-glucopyranoside (12), N6-(4'-hydroxybenzl) -adenosine (13) and beta-sitosterol (14). CONCLUSION: Compounds 6 - 8 and 11 are isolated from this plant for the first time.
