Occurrence, source apportionment and ecological risk assessment of thirty antibiotics in farmland system.

Antibiotics are widely used in medical care, livestock production, and aquaculture. However, antibiotic pollution has attracted increasing global concerns due to their ecological risks after entering into environmental ecosystem via animal excretion, effulent from industrial and domestic sewage treatment facilities. In this study, 30 antibiotics were investigated in soils and irrigation rivers using ultra-performance liquid chromatography-triple quadrupole tandem mass spectrometer. This study evaluated the occurrence, source apportionment, and ecological risks of these target compounds in soils and irrigation rivers (i.e., sediments and water) of farmland system by using principal component analysis-multivariate linear regression (PCA-MLR) and risk quotients (RQ). The concentration range of antibiotics in soils, sediments, and water was 0.38-689.58 ng/g, 81.99-658.00 ng/g, and 134.45-1547.06 ng/L, respectively. In soils, the most abundant antibiotics were quinolones and antifungals with an average concentration of 30.00 ng/g and 7.69 ng/g, respectively, contributing to 40% of total antibiotics. Macrolides were the most frequently detected antibiotics in soils with an average concentration of 4.94 ng/g. In irrigation rivers, quinolones and tetracyclines, the most abundant antibiotics, accounted for 78% and 65% of antibiotics in water and sediments, respectively. Higher antibiotic contamination of irrigation water was primarily distributed in highly populated urban areas, while increasing antibiotic contamination of sediments and soils was particularly observed in rural areas. PCA-MLR analysis indicated that antibiotic contamination in soils was mainly ascribed to the irrigation of sewage-receiving water body and manure application of livestock and poultry farming, which cumulatively contributed to 76% of antibiotics. According to RQ assessment, quinolones in irrigation rivers posed high risk to algae and daphnia, contributing 85% and 72% to the mixture risk, respectively. In soils, macrolides, quinolones and sulfonamides were responsible for more than 90% to the mixture risk of antibiotics. Ultimately, these findings can improve our fundamental knowledge on contamination characteristics and source pathways towards risk management of antibiotics in farmland system.

Occurrence, Distribution and Ecological Risk of Bisphenol Analogues in the Surface Water from a Water Diversion Project in Nanjing, China.

Due to the widespread use of bisphenol analogues (BPs) as alternatives to bisphenol A (BPA), considerable attention for health risk has been shown in aquatic ecosystems. The occurrence and distribution of six BPs were researched in a soluble phase (<10-3 µm), colloidal phase (10-3 µm to 1 µm), and suspended particulate matter (SPM >1 µm) in a water diversion project of Nanjing, China. Except for bisphenol Z, all BPs were detected in two or three phases, where the total concentrations of detected BPs were 161-613 ng/L, 5.19-77.2 ng/L, and 47.5-353 ng/g for the soluble phase, colloidal phase, and SPM, respectively. Among the detected compounds, BPA is still the dominant BPs in the soluble and colloidal phases, which is followed by bisphenol-S , while bisphenol-AF was the major contaminant in SPM, followed by BPA. The mean contribution proportions of colloids were 1-2 orders of magnitude higher than SPM, which suggests that colloids have a clear impact on regulating BPs' environmental behaviors. In terms of spatial distribution, the water diversion project could reduce the pollution levels of BPs, which might further affect the ecological security of the Yangtze River.

[Distribution and Environmental Risk of Pharmaceutically Active Compounds in the Traditionally Aqueous Phase of Effluent-receiving Rivers].

Colloid media are not only an important "sink" for pollutants in the aquatic environment, but also a crucial regulating unit for the biogeochemical cycle of pollutants. In this study, the distribution and environmental risk levels of ten typical pharmaceutically active compounds (PhACs) in the water phase of effluent-receiving rivers were investigated using cross-flow ultrafiltration, solid-phase extraction, and liquid chromatography-tandem mass spectrometry as the pretreatment and analysis methods. The results showed that the total concentrations of the ten PhACs in the dissolved phase and colloidal phase ranged from 27.2 to 168.1 ng·L-1 and 164.5 to 751.1 ng·g-1, respectively. Ibuprofen (IPF), roxithromycin (ROX), and erythromycin (ETM) are the dominating pollutants in the dissolved phase and colloidal phase, accounting for more than 80% of the total concentration. Strong adsorption properties for ROX, ketoconazole, ETM, and sertraline were found in the colloid phase, their colloid/water distribution coefficients (lgKcol) ranged from 3.2 to 4.0, and the percentage of PhACs absorbed to the colloidal phase reached 21.1%-34.5%. The risk assessment of acute and chronic toxicity to algae, daphnia, and fish showed that only IPF presented a high chronic risk to fish, while the risk levels of the other PhACs were at or below medium risk. It is worth noting that, in comparison with their acute risk, most PhACs have chronic negative effects on higher aquatic organisms.

Properties of Hemoglobin Decolorized with a Histidine-Specific Protease.

This study investigated the application of Aspergilloglutamic peptidase (AGP) on porcine hemoglobin decolorization. AGP from fungus Aspergillus niger is identified to possess a high preference towards the histidine residues. As histidine residues in hemoglobin are known to coordinate the heme group within the globin molecule, we therefore hypothesized that incubating hemoglobin with a histidine-specific protease would efficiently separate the non-heme peptides from the heme-enriched peptides with a minimum degree of hydrolysis. AGP-decolored porcine hemoglobin hydrolysates were assessed on their functional (for example, color, emulsification, foaming, and water binding) and sensory properties. The results were compared with commercially available blood-derived proteins (subtilisin-decolored hemoglobin hydrolysates and plasma protein). It was observed that AGP is able to effectively decolor hemoglobin. The degree of hydrolysis (DH) increased less than 3% using AGP to achieve 90% color reduction of hemoglobin, whereas a DH increase of more than 20% is needed using subtilisin. The AGP-decolored hemoglobin hydrolysates (AGP-Hb) possess good emulsification, foaming, and water binding properties, which are better or comparable with the plasma protein, and much better than the subtilisin-decolored hemoglobin hydrolysates (subtilisin-Hb). The model canned meat with addition of AGP-Hb showed the highest value in hardness, springiness, and chewiness from the texture analysis. Furthermore, the canned meat with AGP-Hb was found to have a better sensory profile than the ones with addition of subtilisin-Hb and plasma protein.

Quantitative phosphoproteomic profiling of PINK1-deficient cells identifies phosphorylation changes in nuclear proteins.

The Parkinson's disease (PD) associated gene PINK1 encodes a protein kinase that mediates the phosphorylation of multiple proteins involved in mitochondrial homeostasis. The broader downstream signaling events mediated by PINK1 kinase activity have not been well documented. We combine quantitative phosphoproteomic strategies with siRNA mediated PINK1 knock down in mammalian cells to identify alterations of phosphorylation events downstream of PINK1. Although down-regulation of PINK1 has no major effect on the proteome expression in these cells, phosphorylation of over one hundred proteins was reduced reflecting basal levels of phosphorylation signaling events downstream of PINK1. Motif analysis of the residues flanking the phosphorylation sites indicates proline-directed kinase specificity. Surprisingly, we found that the downstream signaling nodes included many transcription factors, as well as nuclear proteins involved in DNA and RNA metabolism. Thus, PINK1 dependent phosphorylation signaling may regulate nuclear activities.

Diversity of (dihydro) hydroxycinnamic acid conjugates in Colombian potato tubers.

In potato tuber, caffeic acid (the predominant hydroxycinnamic acid (HCA)), its conjugates (HCAcs; i.e. chlorogenic acid (ChA), crypto-ChA, and neo-ChA), and anthocyanin-linked HCAs have been extensively described in the literature. In contrast, only little information is available on the occurrence of other HCAcs and didydrohydroxycinnamic acid conjugates (DHCAcs). Fifteen Colombian potato cultivars were screened for these less commonly described conjugates by reversed-phase ultrahigh performance liquid chromatography coupled to a diode array detector and a heated electrospray ionisation mass spectrometer. A total of 62 HCAs/HCAcs/DHCAcs were found in extracts from peel and flesh. Among them, only twelve compounds were common to all cultivars in both peel and flesh. The less commonly described compounds accounted for 7.1-20.1% w/w of the total amount of HCAs/HCAcs/DHCAcs in whole tubers, highlighting their contribution to the total phenolic profile of potato tubers. Among all cultivars, the abundance (mg/100 g DW whole tuber) of neo-ChA (0.8-7.4) ranged in similar quantities as the less commonly reported feruloyl octopamine (1.2-5.2), 5-O-feruloyl quinic acid (0.1-7.5), cis-ChA (1.1-2.2), caffeoyl putrescine (0.6-2.5), sinapoyl hexose (0.1-1.8), N(1),N(14)-bis-(dihydrocaffeoyl) spermine (0.2-1.7), N(1),N(10)-bis-(dihydrocaffeoyl) spermidine (1.1-2.6), and N(1),N(5),N(14)-tris-(dihydrocaffeoyl) spermine (trace - 11.1).