1.Isolation and cloning of an aryl-aldehyde dehydrogenase gene from the white-rot fungus Pycnoporus cinnabarinus strain MUCL 39533
Khai Lun Ong ; Siew Ling Liew ; Sahilah Abdul Mutalib ; Abdul Munir Abdul Murad ; Farah Diba Abu Bakar
Malaysian Journal of Microbiology 2015;11(4):391-397
Aims: The white rot fungus Pycnoporus cinnabarinus MUCL 39533 is able to reduce vanillic acid to vanillin. Reduction of
vanillic acid to vanillin catalysed by the key enzyme aryl-aldehyde dehydrogenase has been reported. Here we report the
isolation and cloning of aryl-aldehyde dehydrogenase from P. cinnabarinus strain MUCL 39533.
Methodology and results: An aryl-aldehyde dehydrogenase gene (PcALDH) was isolated from P. cinnabarinus by
producing a partial cDNA sequence fragment of an aryl-aldehyde dehydrogenase gene through PCR. Degenerate PCR
primers were designed based on codons corresponding to conserved amino acid regions of aryl-aldehyde
dehydrogenases of several fungi and bacteria. The full-length PcALDH cDNA was obtained through ReverseTranscription-Polymerase
Chain Reaction (RT-PCR) and Rapid Amplification cDNA Ends (RACE) PCR. PcALDH cDNA
comprises an open reading frame of 1,506 bp that encodes a protein of 501 amino acids. The PcALDH predicted protein
showed the highest amino acid sequence identity (84%) to ALDH from Trametes versicolor. In silico analysis of PcALDH
indicated that it belongs to the ALDH super-family and Class 3 ALDH.
Conclusion, significance and impact study: PcALDH cDNA was successfully isolated and characterized. Important
motifs identified from the highly conserved PcALDH protein indicated that it belongs to the aldehyde dehydrogenase superfamily.
The cDNA clone will be used in expression studies to confirm the catalytic function of the enzyme.
Vanillic Acid
;
Flavoring Agents
2.An estimation of the daily intake of di(2-ethlhexyl) phthalate (DEHP) among workers in flavoring factories.
Jie LU ; Jing ZHANG ; Zhu Tian WANG ; Yong Xiang FAN
Biomedical and Environmental Sciences 2014;27(6):419-425
OBJECTIVETo estimate the daily intake of DEHP among workers in flavoring factories.
METHODS71 workers in two flavoring manufacturers, 27 administrators in those factories and 31 laboratory technicians in a research institute were recruited and assigned to exposure group, control group 1 and control group 2 respectively. Their urinary DEHP metabolites, mono(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), were detected by isotope dilution-ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). The urinary metabolites concentrations were converted into DEHP intake levels using two pharmacokinetic models: the urine creatinine-excretion (UCE) one and the urine volume (UV) one.
RESULTSNo significant differences were found among the three groups. Based on the urinary concentrations of Σ₃MEHP, we got a median daily DEHP intake of 3.22 or 1.85 μg/kg body-weight/day applying the UV or UCE models respectively. Depending on the UV model, three subjects (2.34%) exceeded the RfD value given by US EPA and the P₅₀ of estimate daily DEHP intakes accounted for 16.10% of the RfD value. No subjects exceeded the limitation depending on the UCE model.
CONCLUSIONThe workers in flavoring factories were not supposed to be the high DEHP exposure ones and their exposure level remained at a low risk.
Adult ; Diethylhexyl Phthalate ; urine ; Flavoring Agents ; Humans ; Occupational Exposure ; analysis ; Young Adult
3.Apoptotic Effect of Co-treatment with Curcumin and Cisplatin on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line.
Hyeon Jin SOHN ; In Ryoung KIM ; Yong Ho KIM ; Gyoo Cheon KIM ; Hyun Ho KWAK ; Bong Soo PARK
International Journal of Oral Biology 2014;39(3):159-167
Curcumin is a widely used flavoring agent in food, and it has been reported to inhibit cell growth, to induce apoptosis, and to have antitumor activity in many cancers. Cisplatin is one of the most potent known anticancer agents and shows significant clinical activity against a variety of solid tumors. This study was undertaken to investigate the synergistic apoptotic effects of co-treatment with curcumin and cisplatin on human tongue SCC25 cells. To investigate whether the co-treatment efficiently reduced the viability of the SCC25 cells compared with the two treatments separately, an MTT assay was conducted. The induction and the augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining, and an analysis of DNA hypoploidy. Western blot, MMP and immunofluorescence tests were also performed to evaluate the expression levels and the translocation of apoptosis-related proteins following the co-treatment. In this study, following the co-treatment with curcumin and cisplatin, the SCC25 cells showed several forms of apoptotic manifestation, such as nuclear condensation, DNA fragmentation, reduction of MMP, increased levels of Bax, decreased levels of Bcl-2, and decreased DNA content. In addition, they showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40 (CAD) to the nuclei, and activation of caspase-7, caspase-3, PARP, and DFF45 (ICAD). In contrast, separate treatments of 5 microM of curcumin or 4 microg/ml of cisplatin, for 24 hours, did not induce apoptosis. Therefore, our data suggest that combination therapy with curcumin and cisplatin could be considered as a novel therapeutic strategy for human oral squamous cell carcinoma.
Antineoplastic Agents
;
Apoptosis
;
Blotting, Western
;
Carcinoma, Squamous Cell*
;
Caspase 3
;
Caspase 7
;
Cell Line*
;
Cisplatin*
;
Curcumin*
;
Cytochromes c
;
Cytosol
;
DNA
;
DNA Fragmentation
;
Electrophoresis
;
Flavoring Agents
;
Fluorescent Antibody Technique
;
Humans
;
Tongue*
4.The Neuroprotective Effect of Maltol against Oxidative Stress on Rat Retinal Neuronal Cells.
Yookyung SONG ; Samin HONG ; Yoko IIZUKA ; Chan Yun KIM ; Gong Je SEONG
Korean Journal of Ophthalmology 2015;29(1):58-65
PURPOSE: Maltol (3-hydroxy-2-methyl-4-pyrone), formed by the thermal degradation of starch, is found in coffee, caramelized foods, and Korean ginseng root. This study investigated whether maltol could rescue neuroretinal cells from oxidative injury in vitro. METHODS: R28 cells, which are rat embryonic precursor neuroretinal cells, were exposed to hydrogen peroxide (H2O2, 0.0 to 1.5 mM) as an oxidative stress with or without maltol (0.0 to 1.0 mM). Cell viability was monitored with the lactate dehydrogenase assay and apoptosis was examined by the terminal deoxynucleotide transferase-mediated terminal uridine deoxynucleotidyl transferase nick end-labeling (TUNEL) method. To investigate the neuroprotective mechanism of maltol, the expression and phosphorylation of nuclear factor-kappa B (NF-kappaB), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 were evaluated by Western immunoblot analysis. RESULTS: R28 cells exposed to H2O2 were found to have decreased viability in a dose- and time-dependent manner. However, H2O2-induced cytotoxicity was decreased with the addition of maltol. When R28 cells were exposed to 1.0 mM H2O2 for 24 hours, the cytotoxicity was 60.69 ± 5.71%. However, the cytotoxicity was reduced in the presence of 1.0 mM maltol. This H2O2-induced cytotoxicity caused apoptosis of R28 cells, characterized by DNA fragmentation. Apoptosis of oxidatively-stressed R28 cells with 1.0 mM H2O2 was decreased with 1.0 mM maltol, as determined by the TUNEL method. Western blot analysis showed that treatment with maltol reduced phosphorylation of NF-kappaB, ERK, and JNK, but not p38. The neuroprotective effects of maltol seemed to be related to attenuated expression of NF-kappaB, ERK, and JNK. CONCLUSIONS: Maltol not only increased cell viability but also attenuated DNA fragmentation. The results obtained here show that maltol has neuroprotective effects against hypoxia-induced neuroretinal cell damage in R28 cells, and its effects may act through the NF-kappaB and mitogen-activated protein kinase signaling pathways.
Animals
;
*Apoptosis
;
Blotting, Western
;
Cell Survival
;
Cells, Cultured
;
Disease Models, Animal
;
Flavoring Agents/pharmacology
;
In Situ Nick-End Labeling
;
Oxidative Stress/*drug effects
;
Pyrones/*pharmacology
;
Rats
;
Retinal Ganglion Cells/drug effects/metabolism/*pathology
5.The Emerging Method of Suicide by Electronic Cigarette Liquid: a Case Report.
Journal of Korean Medical Science 2018;33(11):e52-
Electronic cigarettes (ECs) are a device that aerosolize liquid nicotine by heating a solution of nicotine, glycerol and flavoring agents. The awareness and the usage of ECs has increased in many countries. Due to the online sales and the absence of EC regulations, the prevalence of EC usage is especially high in adolescents and young adults. Due to the large amount and the high nicotine concentration of EC liquid, the ingestion for suicide can lead to cardiac death. We had two patients, a 27-year-old male who ingested about 23 mg/kg of nicotine and a 17-year-old female who ingested about 30 mg/kg of nicotine. Both patients presented seizure-like movement and cardiac arrest. They had metabolic acidosis and transient cardiomyopathy. They were ultimately discharged with a cerebral performance category of 2 and 4, respectively. Increasing EC use may produce more cases of medical problems or suicide by nicotine intoxication.
Acidosis
;
Adolescent
;
Adult
;
Cardiomyopathies
;
Commerce
;
Death
;
Eating
;
Electronic Cigarettes*
;
Female
;
Flavoring Agents
;
Glycerol
;
Heart Arrest
;
Heating
;
Hot Temperature
;
Humans
;
Male
;
Methods*
;
Nicotine
;
Poisoning
;
Prevalence
;
Social Control, Formal
;
Suicide*
;
Young Adult