摘要：
This study used response surface methodology to determine the optimal conditions for extraction of polysaccharides from Pyracantha. fortuneana (PSPF), and studied the mechanism of PSPF-inducing apoptosis in human ovarian carcinoma Skov3 cells. Response surface methodology (RSM) were adopted to extract PSPF. The maximum value of polysaccharide yield was obtained under these optimal conditions. PSPF had good potential as an antioxidant. Exposure of cells to PSPF resulted in cytotoxicity through the induction of apoptosis, and the reactive oxygen species were increased, mitochondrial membrane potential decreased, DNA damage (detected as gamma- H2AX and RAD51 foci) was observed in Skov3 cells. In addition, PSPF could induce apoptosis of cancer cells. Therefore, PSPF should be explored as novel potential antioxidants and an anti-tumor drug in a clinical setting.
摘要：
The oxidation of phenolic compounds caused by polyphenol oxidase (PPO) often contributes to the browning and decaying of lotus root. However, methods are limited to solve this problem and to effectively extend the shelf life of fresh lotus. Thus, lactic acid bacteria (LAB) were used in this study as an alternative solution. Michaelies-Menten equations analysis indicated that gallic acid, chlorogenic acid and catechin of lotus were the most optimal substrates of PPO. So Lactobacillus plantarum (LH-B02), Lactobacillus acidophilus (LA-05) and Lactobacillus casei (LC-01) were cultivated at the presence of gradient concentrations of these phenols, presenting different dose-effect relationship. The decomposition of polyphenols by effective strains was detected by HPLC analysis, indicating that after interacted for 30 h, 84.17% of catechin was transformed by LH-B02. When LH-B02 suspension (1.44 × 1011 CFU L−1) were sprayed on the surface of the lotus root for 1, 3, 5, and 8 times, the color loss of treated lotus root was significantly reduced (p < 0.01), compared with the control during the storage of 15 d. Texture properties involving hardness, chewiness, springiness and cohesiveness of the lotus was significantly (p < 0.05) enhanced, especially for the samples sprayed five and eight times, suggesting that LAB could improve the postharvest properties of lotus root.
作者机构：
[岳琪琪; 刘文; 孔萍] College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;Fresh Food Engineering and Technology Research Center of Hubei Province, Wuhan, 430023, China;College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;[侯温甫] College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, 430023, China<&wdkj&>Fresh Food Engineering and Technology Research Center of Hubei Province, Wuhan, 430023, China;[王丽梅; 王宏勋] Fresh Food Engineering and Technology Research Center of Hubei Province, Wuhan, 430023, China<&wdkj&>College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
通讯机构：
College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
摘要：
Lotus (Nelumbo nucifera Gaertn) is a wetland vegetable famous for its nutritional and medicinal value. Phenolic compounds are secondary metabolites that play important roles in the browning of fresh-cut fruits and vegetables, and chemical constituents are extracted from lotus for medicine due to their high antioxidant activity. Studies have explored in depth the changes in phenolic compounds during browning, while little is known about their synthesis during the formation of lotus rhizome. In this study, transcriptomic analyses of six samples were performed during lotus rhizome formation using a high-throughput tag sequencing technique. About 23 million high-quality reads were generated, and 92.14% of the data was mapped to the reference genome. The samples were divided into two stages, and we identified 23,475 genes in total, 689 of which were involved in the biosynthesis of secondary metabolites. A complex genetic crosstalk-regulated network involved in the biosynthesis of phenolic compounds was found during the development of lotus rhizome, and 25 genes in the phenylpropanoid biosynthesis pathway, 18 genes in the pentose phosphate pathway, and 30 genes in the flavonoid biosynthesis pathway were highly expressed. The expression patterns of key enzymes assigned to the synthesis of phenolic compounds were analyzed. Moreover, several differentially expressed genes required for phenolic compound biosynthesis detected by comparative transcriptomic analysis were verified through qRT-PCR. This work lays a foundation for future studies on the molecular mechanisms of phenolic compound biosynthesis during rhizome formation.
作者：
Zhou, Min;Li, Xiaofang;Hou, Wenfu;Wang, Hongxun*;Paoli, George C.;...
期刊：
Frontiers in Microbiology,2019年10:ARTN 2265 ISSN：1664-302X
通讯作者：
Wang, Hongxun;Shi, Xianming
作者机构：
[Zhou, Min; Li, Xiaofang; Hou, Wenfu; Wang, Hongxun] Wuhan Polytech Univ, Sch Food Sci & Engn, Wuhan, Hubei, Peoples R China;[Paoli, George C.] ARS, Mol Characterizat Foodborne Pathogens Res Unit, USDA, Eastem Reg Res Ctr,Most Joint Res Ctr Food Safety, Wyndmoor, PA USA;[Shi, Xianming] Shanghai Jiao Tong Univ, State Key Lab Microbial Metab, Sch Agr & Biol, MOST USDA Joint Res Ctr Food Safety, Shanghai, Peoples R China
通讯机构：
[Wang, Hongxun] W;[Shi, Xianming] S;Wuhan Polytech Univ, Sch Food Sci & Engn, Wuhan, Hubei, Peoples R China. Shanghai Jiao Tong Univ, State Key Lab Microbial Metab, Sch Agr & Biol, MOST USDA Joint Res Ctr Food Safety, Shanghai, Peoples R China.
关键词：
MLST;Salmonella;blaCTX-M-15;blaCTX-M-65;class I integrons;qnrB
摘要：
Salmonella is a leading cause of foodborne disease and is often associated with the consumption of foods of animal origin. In this study, sixty-six Salmonella isolates were obtained from 631 raw meat samples purchased at small retail suppliers in Hubei Province, China. The most prevalent Salmonella serotypes were Thompson (18.2%) and Agona (13.6%). Frequent antimicrobial resistance was observed for the sulfonamides (43.9%), tetracycline (43.9%), and the b-lactams amoxicillin and ampicillin (36.4% for each). Interestingly, a high incidence of resistance to cephazolin was observed in strains of the most common serotype, S. Thompson. Class I integrons were found in 27.3% (18/66) of the isolates and five of these integrons contained different gene cassettes (aacA4C-arr-3-dfr2, dfrA12-aadA21, aadA2, dfrA12-aadA2, dfr17-aadA5). Additional antimicrobial resistance genes, including blaTEM-1, blaCTX- M-65, blaCTX- M-15, qnrB, and qnrS, were also identified among these Salmonella isolates. Results of replicon typing and conjugation experiments revealed that an integron with qnrB and blaCTX- M-15 genes was present on incH12 mobile plasmid in S. Thompson strain. Multilocus sequence typing (MLST) analysis revealed 32 sequence types, indicating that these isolates were phenotypically and genetically diverse, among which ST26 (18.2%) and ST541 (12.1%) were the predominant sequence types. The integrons, along with multiple antimicrobial resistance genes on mobile plasmids, are likely contributors to the dissemination of multidrug resistance in Salmonella.
关键词：
acid-sensing ion channels;Asic2a;Asic4;methylation;morris water maze;walnut oil
摘要：
<jats:title>Abstract</jats:title><jats:p>Although Walnut oil (<jats:styled-content style="fixed-case">WO</jats:styled-content>) has been reported to enhance cognitive function, the underlying molecular mechanisms are not well understood. This study was designed to assess the effects of <jats:styled-content style="fixed-case">WO</jats:styled-content> on spatial memory in rats through modulation of the expression of acid‐sensing ion channel genes, <jats:italic>Asic2a</jats:italic> and <jats:italic>Asic4</jats:italic>. To investigate the effect of <jats:styled-content style="fixed-case">WO</jats:styled-content> on cognitive performance, we supplemented the diet of female rats with <jats:styled-content style="fixed-case">WO</jats:styled-content>. The results showed that supplementation with <jats:styled-content style="fixed-case">WO</jats:styled-content> at doses of 2.2 and 11gkg<jats:sup>−1</jats:sup>day<jats:sup>−1</jats:sup> significantly improved learning and memory. In vitro treatment of rat hippocampal neuronal cells with appropriate doses of <jats:styled-content style="fixed-case">WO</jats:styled-content> revealed a significant increase in the expression of <jats:italic>Asic2a</jats:italic> and <jats:italic>Asic</jats:italic>4 in a dose‐dependent manner at both the <jats:styled-content style="fixed-case">mRNA</jats:styled-content> and protein levels. We conclude that <jats:styled-content style="fixed-case">WO</jats:styled-content> intake might help to prevent cognitive decline, particularly in the elderly, and that <jats:styled-content style="fixed-case">ASIC</jats:styled-content> genes in neurons can be the targets of compounds contained in the oil.</jats:p>
作者机构：
[欧阳何一; 韩千慧; 侯温甫; 周敏; 吴忌] College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;[王宏勋] School of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;[侯温甫; 王宏勋; 周敏] Fresh Food Engineering and Technology Research Center of Hubei Province, Wuhan, 430023, China
摘要：
To investigate the structure, in vitro digestibility and activity of polysaccharides from lotus root, their main fractions named LRPs were isolated and purified by gel filtration chromatography. Structural analyses indicated that: LRPs were alpha-(1 -> 6)-D-heteroglucans mainly composed of Glc-(1 ->, -> 6)-Glc(1 ->, -> 6)-Gal (1 ->, -> 4,6)-Gal- (1 -> and -> 3,6)-Glc-(1 ->, at a molar ratio of 1.00: 4.33: 0.83: 0.13: 1.14; the total molar percentage of other monosaccharides in LRPs, including Man, Rha, GalA and Ara, was 8.10%; the molecular weights of LRPs was in the range of 1.33 kDa to 5.30 kDa. According to the change of molecular weight and the productions of reducing sugar and free monosaccharide, the simulated experiments of salivary, gastric and intestinal digestion confirmed that LRPs were almost undigestible. Moreover, LRPs showed the scavenging ability against DPPH and hydroxyl radicals, the growth inhibition ability against SGC7901 and HepG2 cancer cells in vitro, and the immunostimulating effect on the NO and TNF-alpha productions of macrophages in vitro. LRPs nearly remain their initial structure and activities in upper gastrointestinal tract and have health-improving potentials. (C) 2019 Published by Elsevier B.V.
