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Metabolism of Radiolabeled β-Guaiacyl Ether-Linked Lignin Dimeric Compounds by Phanerochaete chrysosporium 下载免费PDF全文
David A. Weinstein Kanit Krisnangkura Mary B. Mayfield Michael H. Gold 《Applied microbiology》1980,39(3):535-540
Phanerochaete chrysosporium metabolized the radiolabeled lignin model compounds [γ-14C]guaiacylglycerol-β-guaiacyl ether and [4-methoxy-14C]veratrylglycerol-β-guaiacyl ether (VI) to 14CO2 in stationary and in shaking cultures. 14CO2 evolution was greater in stationary culture. 14CO2 evolution from [γ-14C]guaiacyl-glycerol-β-guaiacyl ether and [4-methoxy-14C]veratrylglycerol-β-guaiacyl ether in stationary cultures was two- to threefold greater when 100% O2 rather than air (21% O2) was the gas phase above the cultures. 14CO2 evolution from the metabolism of the substrates occurred only as the culture entered the stationary phase of growth. The presence of substrate levels of nitrogen in the medium suppressed 14CO2 evolution from both substrates in stationary cultures. [14C]veratryl alcohol and 4-ethoxy-3-methoxybenzyl alcohol were formed as products of the metabolism of VI and 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, respectively. 相似文献
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Khongkla Ekkaphot Uppakara Kwanchanok Boonmuen Nittaya Bhukhai Kanit Saengsawang Witchuda 《Cellular and molecular neurobiology》2022,42(7):2337-2353
Cellular and Molecular Neurobiology - The Cath.a-differentiated (CAD) cell line is a central nervous system-derived catecholaminergic cell line originating from tyrosine hydroxylase (TH)-producing... 相似文献
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Mefenamic acid, a non-steroidal antiinflammatory drug (NSAID), directly and dose-dependently exhibits neuroprotective activity. In our study, we investigated the effects of mefenamic acid against d-serine on oxidative stress in the hippocampus, cortex and cerebellum of rats. Furthermore, the potential inflammatory and apoptotic effects of d-serine and potential protective effect of mefenamic acid were determined at mRNA and protein levels of TNF-α, IL-1β, Bcl-2 and Bax. We found that d-serine significantly increased oxidative stress, levels of inflammation- and apoptosis-related molecules in a region specific manner. Mefenamic acid treatment provided significant protection against the elevation of lipid peroxidation, protein oxidation, levels of TNF-α, IL-1β and Bax. As a conclusion, we suggest that d-serine, as a potential neurodegenerative agent, may have a pivotal role in the regulation of oxidative stress, inflammation and apoptosis; and NSAIDs, such as mefenamic acid, may assist other therapeutics in treating disorders where d-serine-induced neurotoxic mechanisms are involved in. 相似文献
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Lakkana Laopaiboon Niphaphat Phukoetphim Kanit Vichitphan Pattana Laopaiboon 《World journal of microbiology & biotechnology》2008,24(9):1633-1641
Biodegradation of an aldehyde biocide, glutaraldehyde (GA), in a single-stage laboratory-scale rotating biological contactor
(RBC) was studied under biocide or organic loadings (OL) of 12–66 g COD m−2 day−1 and hydraulic retention times (HRT) of 0.6–3.0 h. Biofilms on the RBC were acclimated in 180 ppm GA at a hydraulic loading
(HL) of 0.18 m3 m−2 day−1 and the HRT of 0.60 h. The results showed that under a constant initial chemical oxygen demand (COD) concentration and sufficient
mineral salts available, the degree of GA removal in the RBC system was increased with either decreasing OL or increasing
HRT. After a period of acclimation, treatment efficiency in terms of GA removal by the RBC receiving GA as a sole carbon source
was 89%. The biofilms played an important role in biodegradation of biocide in the RBCs, whereas bio-oxidation of their planktonic
counterparts was totally inhibited in the presence of 50 ppm GA. The biochemical oxygen demand (BOD) test could be used as
an appropriate analytical procedure for investigating the efficiency of wastewater treatment units when seed was acclimated
and had adequate amount. 相似文献
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Ezgi Turunc Bayrakdar Guliz Armagan Yigit Uyanikgil Lutfiye Kanit Ersin Koylu Ayfer Yalcin 《Cell biochemistry and function》2014,32(7):557-564
Alzheimer's disease (AD) is the most common form of dementia and is characterized by the presence of senile plaques and neurofibrillary tangles, along with synaptic loss. The underlying mechanisms of AD are not clarified yet, but oxidative stress and mitochondrial dysfunction are important factors. Overactivation of poly(adenosine diphosphate ribose) polymerase‐1 (PARP‐1) enzyme has been known to cause neuroinflammation and cell death in neurodegenerative processes. The aim of the present study was to investigate the protective effects of the PARP‐1 inhibitors, 3‐aminobenzamide (3‐AB) and nicotinamide (NA), against amyloid β peptide (1–42) (Aβ(1–42))‐induced oxidative damage and mitochondrial reduction capacity on isolated synaptosomes. Rats were injected intraperitoneally with 3‐AB (30–100 mg kg?1), NA (100–500 mg kg?1) or with saline for 7 days. Synaptosomes were incubated with 10–30 μM Aβ(1–42) or saline for 6 h at 37 °C. Ex vivo Aβ(1–42) treatment significantly induced oxidative stress and mitochondrial dysfunction in synaptosomes of the saline group, while synaptosomes of 3‐AB and NA groups showed significant decreases in lipid peroxidation, reactive oxygen species production and protein oxidation. Moreover, both NA and 3‐AB were able to improve the mitochondrial reduction capacity against Aβ(1–42). These data suggest that NA and 3‐AB may have protective effects in neurodegenerative processes because of the reduced levels of oxidative stress and the improvement of mitochondrial function. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Gas chromatographic characterizations of fatty alcohols are generally carried out as the free alcohols, trimethyl silyl or acetyl derivatives. In this study, transesterification/acetylation of long chain fatty alcohols is simply carried out by dissolving the alcohol in ethyl/methyl acetate and passing through a micro-column packed with solid NaOH. Reaction times are slightly different for alcohols of different chain length. Rice bran alcohols of 24–34 carbon atom are successfully acetylated. Also, castor oil methyl ester can be interesterified but with longer reaction time. 相似文献
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Khongkla Ekkaphot Uppakara Kwanchanok Boonmuen Nittaya Bhukhai Kanit Saengsawang Witchuda 《Cellular and molecular neurobiology》2022,42(7):2355-2355
Cellular and Molecular Neurobiology - 相似文献
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Histology of gastritis and Helicobacter pylori infection in Thailand: a nationwide study of 3776 cases 总被引:2,自引:0,他引:2
Atisook K Kachinthorn U Luengrojanakul P Tanwandee T Pakdirat P Puapairoj A 《Helicobacter》2003,8(2):132-141
Background. Dyspepsia is a very common problem in Thailand. Etiology of gastritis, incidence of Helicobacter pylori and mode of transmission of Helicobacter pylori infection in the country was proposed. Methods. A nation‐wide study of gastric biopsy in 3776 dyspeptic patients from six different geographic regions for incidence of gastritis, type of gastritis, incidence of H. pylori infection, gastric atrophic change and intestinal metaplasia in three age‐groups of each region was done. Results. 58.7% of dyspeptic patients had histological gastritis. Pangastritis was the most common type (77.3%) with mostly mild active inflammation (60.6%) and was found most commonly in the age group 31–60 years. Incidence of gastritis was slightly lower in the coastal and peninsular community compared with the mountain, jungle, semiarid plateau and fertile plain communities. Geographic factor, socioeconomic status and dietary habit were proposed to be important factors in inducing gastritis. H. pylori infection was found in 48.2% of dyspeptic patients with high incidence in the age‐group 31–60 years (63.7%) and 98.2% of H. pylori infection was found to be associated with gastritis. Semi‐arid plateau, mountain, jungle and fertile plain communities had high incidences of H. pylori infection varying from 54.0 to 67.1% while the coastal and peninsular communities had low incidences of 32%. Oral to oral spread is proposed to be the mode of bacterial transmission. Incidences of gastric atrophic change and intestinal metaplasia were low in this country and were found in 11.6% and 8.2% of subjects, respectively, with no significantly different distribution in geographic regions. Type I or intestinal type was found to be the most common type of intestinal metaplasia. 相似文献
10.
Gold Michael H. Mayfield Mary B. Cheng Therese M. Krisnangkura Kanit Shimada Mikio Enoki Akio Glenn Jeffrey K. 《Archives of microbiology》1982,132(2):115-122
A pleiotropic mutant of Phanerochaete chrysosporium 104-2 lacking phenol oxidase and unable to form fruit bodies and a revertant strain 424-2 were isolated after UV mutagenesis. Strains 104-2 and 424-2 had no apparent dysfunction in primary metabolism with glucose as a carbon source. Unlike the wild type strain and strain 424-2, strain 104-2 was unable to evolve 14CO2 from 14C ring, side chain and 3-O-14C-methoxy labeled lignin. In addition, strain 104-2 was unable to evolve 14CO2 from a variety of lignin model compounds including 14C-4-methoxy labeled veratrylglycerol--guaiacyl (V) ether, -14C-guaiacylglycerol--guaiacyl ether (VI), as well as 1-(14C-4-methoxy, 3-methoxyphenyl)1,2 propene (III) and 1-(14C-4-methoxy-3-methoxyphenyl) 1,2 dihydroxypropane (IV). The addition of peroxidase/H2O2 to cultures of strain 104-2 did not alter its capacity to degrade the labeled lignins. A variety of unlabeled lignin model compounds previously shown to be degraded by the wild type organism including -aryl ether dimers and diaryl propane dimers were also not degraded by the mutant 104-2. The revertant strain 424-2 regained the capacity to degrade these compounds. The substrates described are degraded by oxygen requiring system(s) expressed during the secondary phase of growth, suggesting this pleiotropic mutant is possibly defective in the onset of postprimary metabolism. The inability of the mutant to produce the secondary metabolite veratryl alcohol and to elaborate enzymes in the veratryl alcohol biosynthetic pathway supports this hypothesis.Abbreviations GLC
gas liquid chromatography
- TMSi
trimethylsilyl
- MS
mass spectrometry
- LDS
lignin degrading system 相似文献