Read by QxMD icon Read

Polyphenol oxidase

Xiaoxi Zhang, Wenxing Zhou, Hui Liu, Erlei Bai, Jizhou Zhang, Zengwen Liu
To investigate the comprehensive remediating effects of plant residues on biological and chemical properties and the long-term dynamics of these effects, litter from Caragana korshinskii (caragana) or Ziziphus jujuba var. spinosa (jujube) was mixed with three types of soil that were contaminated with 12.49, 27.54, and 45.37 g kg-1 of petroleum. The mixtures were incubated at 20-25 °C with consistent soil moisture for 360 days. Subsequently, the litter impacts on the soil microbial population, the activities of 12 types of soil hydrolytic, and redox enzymes related to the cycling of C, N, and P, and the available N, P, and K contents were determined during the incubation...
March 16, 2019: Environmental Science and Pollution Research International
Shanfa Lu
MIRNA (MIR) gene origin and early evolutionary processes, such as hairpin precursor sequence origination, promoter activity acquirement and the sequence of these two processes, are fundamental and fascinating subjects. Three models, including inverted gene duplication, spontaneous evolution and transposon transposition, have been proposed for de novo origination of hairpin precursor sequence. However, these models still open to discussion. In addition, de novo origination of MIR gene promoters has not been well investigated...
March 14, 2019: RNA Biology
Mohsen Khosravi, Adeleh Poursaleh, Ghasem Ghasempour, Shaikhnia Farhad, Mohammad Najafi
Atherosclerosis is a cardiovascular disease known widely in the world. Several hypothesizes are suggested to be involved in the narrowing of arteries during process of atherogenesis. The oxidative modification hypothesis is related to oxidative and anti-oxidative imbalance and is most investigated. The aim of this study was to review the role of oxidative stress in atherosclerosis. Furthermore, it describes the roles of oxidative/anti-oxidative enzymes and compounds in the macromolecular and lipoprotein modifications and triggering the inflammatory events...
December 1, 2018: Biological Chemistry
Monika A Olszewska, Joanna Kolodziejczyk-Czepas, Magdalena Rutkowska, Anna Magiera, Piotr Michel, Marcin W Rejman, Pawel Nowak, Aleksandra Owczarek
Polyphenol-rich plant extracts might alleviate the negative impact of oxidative stress and inflammation, but careful phytochemical standardisation and evaluation of various mechanisms are required to fully understand their effects. In this context, flower extracts of Sorbus aucuparia L.-a traditional medicinal plant-were investigated in the present work. The LC-MS/MS profiling of the extracts, obtained by fractionated extraction, led to the identification of 66 constituents, mostly flavonols (quercetin and sexangularetin glycosides with dominating isoquercitrin), pseudodepsides of quinic and shikimic acids (prevailing isomers of chlorogenic acid and cynarin), and flavanols (catechins and proanthocyanidins)...
2019: Oxidative Medicine and Cellular Longevity
Ioannis Kampatsikas, Aleksandar Bijelic, Annette Rompel
Polyphenol oxidases (PPOs) contain the structurally similar enzymes tyrosinases (TYRs) and catechol oxidases (COs). Two cDNAs encoding pro-PPOs from tomato (Solanum lycopersicum) were cloned and heterologously expressed in Escherichia coli. The two pro-PPOs (SlPPO1-2) differ remarkably in their activity as SlPPO1 reacts with the monophenols tyramine (kcat  = 7.94 s-1 ) and phloretin (kcat  = 2.42 s-1 ) and was thus characterized as TYR, whereas SlPPO2 accepts only diphenolic substrates like dopamine (kcat  = 1...
March 11, 2019: Scientific Reports
Eunhee Chung, Salvatore N Campise, Hayli E Joiner, Michael D Tomison, Gurvinder Kaur, Jannette M Dufour, Lillian Cole, Latha Ramalingam, Naima Moustaid-Moussa, Chwan-Li Shen
Skeletal muscle is the major site for glucose uptake and thus plays an important role in initiating insulin resistance in type 2 diabetes mellitus. This study evaluated the effects of tocotrienols (TT) and green tea polyphenols (GTP) individually or in combination on glucose homeostasis and skeletal muscle metabolism in obese mice with insulin resistance and elevation of blood glucose. Forty-eight male mice were fed a high-fat diet and assigned to 4 groups in a 2 (no TT vs. 400 mg TT/kg diet) × 2 (no GTP vs...
February 10, 2019: Journal of Nutritional Biochemistry
Amna Shoaib, Zahra Nisar, Nafisa, Arshad Javaid, Saba Khurshid, Sidrah Javed
Cr(VI) tolerance level of phytopathogenic fungus viz., Macrophomina phaseolina (Tassi) Goid was assessed through growth, morphological, physiological, and metal accumulation assays. Initially, the fungus growth assays indicated that the fungus can grow over concentration range of 20-3000 ppm and exhibited high tolerance index (0.88-1.00) and minimum inhibitory concentration at 3500 ppm of Cr. Observations under compound and scanning electron microscope un-revealed the structural features of hyphae under Cr stress as thick-walled, aggregated, branched, short and broken, along with attachment of irregular objects on them...
March 7, 2019: Environmental Science and Pollution Research International
Bingzhi Chen, Guohong Wu, Ling Li, Qi Wei, Qiangui Zhong, Xiaoning Chen, Kaiqian Xiao, Baogui Xie, Yuji Jiang
The effects of paper containing different concentrations of 1-methylcyclopropene (1-MCP) on the quality of Chinese mushrooms were investigated. Mushrooms were first stored with paper containing 0, 0.25, 0.50, 0.75, 1.00, or 1.25 μl L-1 1-MCP at 15 ± 1°C for 12 hr and then continued for up to 8 days. 1-MCP reduced the respiratory peak, weight loss, degree of cap browning, relative leakage rate, and soluble solid content, and delayed the change in the surface hue angle. Mushrooms exposed to paper containing 1-MCP maintained firmness and sensory attributes...
February 2019: Food Science & Nutrition
Ihsan Ullah, Bassam Oudh Al-Johny, Khalid M S Al-Ghamdi, Hind A A Al-Zahrani, Yasir Anwar, Ahmad Firoz, Naser Al-Kenani, Mohammed Ali Ahmed Almatry
Cadmium (Cd) is a toxic heavy metal and an abiotic stressor to plants; however, inoculation of endophytic bacteria can raise resistance in plants against Cd, as well as improve plant growth. In the present study, two endophytic bacterial strains were isolated from Solanum nigrum, identified as Serratia sp. IU01 and Enterobacter sp. IU02 by 16S DNA sequencing. Both IU01 and IU02 were tolerant up to 9.0 mM of Cd in culture broth and successive increase in Cd concentration from 0 mM to 9.0 mM, led to an increase in the SOD enzyme activity of the isolates...
February 28, 2019: Ecotoxicology and Environmental Safety
Ioannis Kampatsikas, Aleksandar Bijelic, Matthias Pretzler, Annette Rompel
The conversion of inactive pro-polyphenol oxidases (pro-PPOs) to the active enzyme results from the proteolytic cleavage of its C-terminal domain. Herein, a peptide mediated cleavage process that activates pro-MdPPO1 (Malus domestica) is reported. Mass spectrometry, mutagenesis studies and X-ray crystal structure analysis of pro-MdPPO1 (1.35 Å) and two separated C-terminal domains, one obtained upon self-cleavage (Ccleaved) of the pro-MdPPO1 (1.35 Å) and a second one produced independently (Csole) (1.05 Å), were applied to identify the structural features for the observed self-cleavage...
March 2, 2019: Angewandte Chemie
Anthony Dobi, Susana B Bravo, Bryan Veeren, Beatriz Paradela-Dobarro, Ezequiel Álvarez, Olivier Meilhac, Wildriss Viranaicken, Pascal Baret, Anne Devin, Philippe Rondeau
Advanced glycation end-products (AGEs) trigger multiple metabolic disorders in the vessel wall that may in turn lead to endothelial dysfunction. The molecular mechanisms by which AGEs generate these effects are not completely understood. Oxidative stress plays a key role in the development of deleterious effects that occur in endothelium during diabetes. Our main objectives were to further understand how AGEs contribute to reactive oxygen species (ROS) overproduction in endothelial cells and to evaluate the protective effect of an antioxidant plant extract...
March 1, 2019: Free Radical Research
Lei Tian, Shaohua Shi, Li Ji, Fahad Nasir, Lina Ma, Chunjie Tian
Panax ginseng is an important medicinal herb due to its ability to strengthen the human immune system. However, due to the increasing needs of ginseng in medicine, the continuous cropping of ginseng has become more common and has resulted in increased problems with fungal decay. Thus, chemical fungicides are commonly used in ginseng plantings, which have caused fungicide residue problems. As an alternative control measure, biocontrol bacteria can be used to manage fungal pathogens. Additionally, these bacteria are environmentally friendly and can also improve stress tolerance in plants...
September 2018: International Microbiology: the Official Journal of the Spanish Society for Microbiology
Yuwei Liu, Fan Yang, Wanqin Yang, Fuzhong Wu, Zhenfeng Xu, Yang Liu, Li Zhang, Kai Yue, Xiangyin Ni, Liying Lan, Ya Chen, Bo Tan
Naphthalene has been widely used to study the role of soil fauna, but its potential non-target effects on soil enzyme activity remain unknown in subalpine forests. We added naphthalene for two years and determined the effect of such additions on the abundance of soil fauna and soil enzyme activities (β-glucosidase, cellobiohydrolase, invertase, peroxidase, polyphenol oxidase, N-acetyl-β-D-glucosaminidase, leucine arylamidase, urease, nitrate reductase and nitrite reductase) in a subalpine forest. Naphthalene could efficiently suppress the individual density and population of soil fauna in situ...
February 26, 2019: Scientific Reports
Marziyeh Jalil Sheshbahreh, Mohsen Movahhedi Dehnavi, Amin Salehi, Babak Bahreininejad
Echinacea purpurea (L.) is one of the most important medicinal plants in the world showing different biochemical reactions as affected by drought stress and nitrogen fertilizer. The purpose of this study was to determine the effect of nitrogen on soluble protein, enzyme activities, carotenoids metabolism, greenness and biological yield of the Echinacea purpurea under different levels of irrigation. The experiment was conducted in a research field in Iran during 2013-2015. Irrigation treatments included irrigation after 25, 50 and 75% soil water depletion, and nitrogen sources were no nitrogen (N), nitroxin, 40 kg N ha-1 , 40 kg N ha-1  + nitroxin and 80 kg N ha-1 ...
January 2019: Physiology and Molecular Biology of Plants: An International Journal of Functional Plant Biology
Yongxu Han, Jun-Hu Cheng, Da-Wen Sun
Food endogenous enzymes have impacts on color, texture and flavor of foods during food processing or preservation. Cold plasma is a novel non-thermal food processing technology, which has been extensively studied for contamination elimination and shelf life extension of foods. Particularly, much work has been reported about the effects of cold plasma on enzyme activities and alterations about enzymes conformational structures. It is thus necessary to understand the mechanisms of actions and applications of cold plasma technology in the conformation of food endogenous enzymes...
February 23, 2019: Critical Reviews in Food Science and Nutrition
Bo Wang, Biting Bian, Chunlei Wang, Changxia Li, Hua Fang, Jing Zhang, Dengjing Huang, Jianqiang Huo, Weibiao Liao
Hydrogen gas (H2) plays an important role in plant development and stress responses. Here, cucumber (Cucumis sativus L.) explants were used to investigate the roles of H2 in adventitious root development under cadmium (Cd) stress and its physiological mechanism. The results showed that hydrogen-rich water (HRW) promoted adventitious rooting under Cd stress and 50% HRW obtained the maximal biological response. Compared with Cd treatment, HRW + Cd treatment significantly reduced the content of malondialdehyde (MDA), hydrogen peroxide (H2O2), superoxide radical (O2-), thiobarbituric acid reactive substances (TBARS), ascorbic acid (AsA) and reduced glutathione (GSH), as well as relative electrical conductivity (REC), lipoxygenase (LOX) activity, AsA/docosahexaenoic acid (DHA) ratio, and GSH/oxidized glutathione (GSSG) ratio, while increasing DHA and GSSG content...
2019: PloS One
Jiaoyan Ren, Linfeng Liao, Shuaiming Shang, Yamei Zheng, Wanqian Sha, Erdong Yuan
The polyphenols (PF) from Platycladus Orientalis (L.) Franco leaves were purified by using 10 different macroporous adsorption resins. HPD-722 resin showed the best adsorption and desorption capacities. The static and dynamic adsorption and desorption of PF on HPD-722 resin were studied and the total polyphenols were separated into two fractions, PF-A and PF-B. PF-A and PF-B demonstrated similar scavenging activity of free radical (DPPH, ABTS, hydroxyl radical, superoxide anion). The scavenging activity of PF-A and PF-B on hydroxyl radical and superoxide anion radical reached the equal levels of vitamin C and gallic acid...
February 19, 2019: Journal of Food Science
Quan Li, Xiaoxiao Chang, Hong Wang, Charles Brennan, Xinbo Guo
This study followed the flesh reddening of Sanhua plum from the surface to the center during fruit development. Five key stages were identified based on colour changes during fruit ripening full-green (FG), red-appeared (RA), half-red (HR), full-red (FR) and purple-red (PR). Fruits were collected and analyzed for phytochemicals and antioxidant properties. Concurrently, the transcript levels of genes associated with phenolic, flavonoid and anthocyanin production were investigated. The titratable acid (TA) content of Sanhua plum decreased during development, while total soluble sugar (TSS) content increased...
February 12, 2019: Journal of Agricultural and Food Chemistry
Klaudia Magierowicz, Edyta Górska-Drabik, Cezary Sempruch
Nowadays, Acrobasis advenella is considered a pest of the highest economic significance in black chokeberry plantations, negatively affecting the quantity and quality of fruits. The aim of this study was to investigate the effect of Satureja hortensis essential oil and its main constituent, carvacrol, on the life cycle and physiology of A. advenella. The metabolic activity of both preparations was evaluated against insect α- and β- glucosidase, catalase, peroxidase and polyphenol oxidase. The results showed S...
January 2019: Pesticide Biochemistry and Physiology
Ranabir Sahu, Tarun K Dua, Sonjit Das, Vincenzo De Feo, Saikat Dewanjee
The present investigation has been undertaken to reveal the protective mechanism of polyphenolics extract of whole wheat grains (WWGPE), ferulic acid and apigenin against doxorubicin (Dox)-induced cardio-toxicity. WWGPE, apigenin, and ferulic acid exhibited concentration dependent cyto-protective effect against Dox (1 μM) in rat cardiomyocytes. Dox treatment significantly (p < 0.01) induced oxidative stress in the myocardial cells via excessive ROS production, increase in iNOS expression, NADPH oxidase activation, Nrf-2/HO-1 impairment, and inactivation of cellular redox defense system...
February 5, 2019: Food and Chemical Toxicology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"