Ellagic acid inhibits oxidized low-density lipoprotein (OxLDL)-induced metalloproteinase (MMP) expression by modulating the protein kinase C-α/extracellular signal-regulated kinase/peroxisome proliferator-activated receptor γ/nuclear factor-κB (PKC-α/ERK/PPAR-γ/NF-κB) signaling pathway in endothelial cells

Previous studies have shown that vascular endothelium-derived matrix metalloproteinases (MMPs) contribute to the destabilization of atherosclerotic plaques, a key event triggering acute myocardial infarction. In addition, studies have reported that the PKC-MEK-PPARγ signaling pathway is involved in oxidized low-density lipoprotein (oxLDL)-induced expression of MMPs. Ellagic acid, a phenolic compound found in fruits and nuts, has potent antioxidant, anti-inflammatory, and anticancerous properties. However, the molecular mechanisms underlying its antiatherogenic effects remain to be clarified. This study aimed to assess whether the effects of ellagic acid on the fibrotic markers MMP-1 and MMP-3 are modulated by the PKC-ERK-PPAR-γ signaling pathway in human umbilical vein endothelial cells (HUVECs) that have been exposed to oxLDL. It was found that ellagic acid significantly inhibited oxLDL-induced expressions of MMP-1 and MMP-3. Pretreatment with ellagic acid and DPI, a well-known ROS inhibitor, attenuated the oxLDL-induced expression and activity of PKC-α. In addition, ellagic acid as well as pharmacological inhibitors of ROS, calcium, and PKC strongly suppressed the oxLDL-induced phosphorylation of extracellular signal-regulated kinase (ERK) and NF-κB activation. Moreover, ellagic acid ameliorated the oxLDL-induced suppression of PPAR-γ expression. In conclusion, the data suggest that ellagic acid elicits its protective effects by modulating the PKC-α/ERK/PPAR-γ/NF-κB pathway, resulting in the suppression of ROS generation and, ultimately, inhibition of MMP-1 and MMP-3 expression in HUVECs exposed to oxLDL.     

Quercetin and isorhamnetin glycosides in onion (Allium cepa L.): varietal comparison, physical distribution, coproduct evaluation, and long-term storage stability

During onion processing, the outer dried protective layer (outer paper layer) and first two fleshy leaf layers are removed. This coproduct material is a potential commercial source of flavonoids especially quercetin. In the following study, the flavonoid composition was determined in coproduct materials and the press cake (material generated after juice extraction) in several commercially important onion varieties grown in California. Flavonoids were characterized and quantified using LC-(ESI)MS/MS and HPLC. The long-term stability of quercetin glycosides was assessed in dried coproduct materials stored at 4 and 22 °C over a 12 month period. In all varieties, the predominant forms of quercetin were the quercetin 3,4'-O-glucoside and 4'-O-glucoside. The first layer had significantly higher levels of flavonoids than the outer paper, second, and inner flesh layers on a DW basis (p < 0.05). Allium cepa "Milestone" contained the highest levels (p < 0.05) of flavonoids (1703 mg/100 g on a dry weight basis (DW). Onion press cake had significantly higher levels of total quercetin as compared with fresh onions (p < 0.05). The levels of 4'-O-glucoside significantly decreased during the first month of storage and remained stable for 12 months of storage at either 4 or 22 °C (p < 0.05).     

Occurrence and Environmental Fate of Veterinary Antibiotics in the Terrestrial Environment

A wide variety of veterinary antibiotics (VAs) has been detected in environmental water samples, and this is of potential environmental concern due to their adverse effects. In particular, the potential for development of antibiotic-resistant bacteria has raised social concerns leading to intensive investigation regarding the influence of antibiotics on human and ecosystem health. One of the main sources of antibiotic effluence to the environment is livestock manures that often contain elevated levels of VAs that survive normal digestive procedures following medication in animal husbandry because unlike human waste, waste generated on farms does not undergo tertiary wastewater treatment, and consequently, the concentration of antibiotics entering the environment is expected to be larger from farming practices. Animal feed is often supplemented with VAs to promote growth and parasite resistance in the medicated animals, and this practice typically resulted in higher use of VAs and consequential excretion from livestock through urine and feces. The excretion rate varied depending on the type of VA used with around 75, 90, and 50?C100% being excreted for chlortetracycline, sulfamethazine, and tyolsin, respectively. The excreted VAs that initially present in livestock manures were degraded more than 90% when proper composting practice was used, and hence, this can be employed as a management strategy to decrease VA environmental loads. The reduction of VA concentrations during composting was mainly attributed to abiotic processes rather than biotic degradation. The VAs released to soils by the application of manure and manure-based composts can be degraded or inactivated to various degrees through abiotic process such as adsorption to soil components. Depending on the antibiotic species and soil properties, residues can be transferred to groundwater and surface water through leaching and runoff and can potentially be taken up by plants.     

Removal of Phosphate from Aqueous Solution by Functionalized Mesoporous Materials

In the present study, the applications of mesoporous materials based on silica, namely post-synthesized, one-pot synthesized, and pure MCM-41, were investigated for the removal of phosphate from aqueous solution. The mesostructures were confirmed by X-ray diffraction, Brunauer?CEmmett?CTeller, Fourier transform spectroscopy, and transmission electron microscopy. The absorptions of phosphate by the mesoporous adsorbents were examined, with different adsorption models used to describe the equilibrium and kinetic data. The maximum adsorption capacities of the mesostructure adsorbents were found to be 45.162, 40.806, and 31.123 mg g^?C1 for the post-synthesized, one-pot synthesized, and pure MCM-41, respectively. The kinetic data showed that the adsorptions of phosphate onto the post-synthesized and pure MCM-41 followed the pseudo-first-order kinetic model, whereas the one-pot synthesized adsorbent was described by the pseudo-second-order model.     

Characterization of codon-optimized recombinant candida rugosa lipase 5 (LIP5)

Recombinant Candida rugosa lipase 5 (LIP5) has been functionally expressed along with other isoforms in our laboratory. However, the characterization and codon optimization of LIP5 have not been done. In this work, we characterized, codon-optimized and compared LIP5 with commercial lipase. LIP5 activity on hydrolysis of p-nitrophenyl (p-NP) butyrate was optimal at 55 °C as compared with 37 °C of the commercial lipase. Several assays were also performed to determine the substrate specificity of LIP5. p-NP butyrate (C(4)), butyryl-CoA (C(4)), cholesteryl laurate (C(12)), and N-carbobenzoxy-l-tyrosine-p-nitrophenyl ester (l-NBTNPE) were found as preferred substrates of LIP5. Interestingly, LIP5 specificity on hydrolysis of amino acid-derivative substrates was shown to be the highest among any lipase isoforms, but it had very weak preference on hydrolyzing triacylglycerol substrates. LIP5 also displays a pH-dependent maximum activity of a lipase but an esterase substrate preference in general. The characterization of LIP5 along with that of LIP1-LIP4 previously identified shows that each lipase isoform has a distinct substrate preference and catalytic activity.     

山西猪场猪蓝耳病并发猪胸膜肺炎放线杆菌的病毒鉴定及细菌分离鉴定以及治疗方案

2020年2月份山西某大型规模猪场育肥猪突发呼吸困难,无过多症状表现,即突然死亡,发病率为2%,死亡率1.5%左右。实验室以病死猪为研究对象,综合死亡猪只脏器病变状况观察,无菌采集病死猪的肺脏、肝脏、脾脏病料,进行RT-PCR检测猪蓝耳病原;用含1%NAD和5%胎牛血清的TSA琼脂培养基进行细菌分离培养和纯化,经形态学鉴定、PCR鉴定、16Sr RNA基因序列进化树构建等方法,结果显示:该发病猪群为猪繁殖与呼吸障碍综合征并发猪胸膜肺炎放线杆菌感染。药敏试验结果显示:该猪胸膜肺炎放线杆菌对安普霉素、硫酸黏菌素、替米考星+氟苯尼考、替米考星+阿莫西林、氟苯尼考、头孢噻呋钠+硫酸黏菌素、头孢喹肟、头孢噻呋钠+新霉素、替米考星+头孢噻呋钠、多西环素+氟苯尼考、头孢噻呋钠+阿莫西林、阿莫西林+克拉维酸钾、头孢噻呋钠+恩诺沙星、新霉素、头孢噻呋钠、安普霉素+头孢噻呋钠敏感。对恩诺沙星耐药。本实验室根据临床及检测结果制定治疗方案,为该猪场的猪繁殖与呼吸障碍综合征并发猪胸膜肺炎的临床诊断及用药提供了理论依据。