The 4-hydroxyphenylacetate 3-hydroxylase (4HPA3H), originated from Escherichia coli, converts p-coumaric acid to caffeic acid. In order to improve the efficiency of caffeic acid biosynthesis, we engineered E. coli for overexpression of 4HPA3H. The high-density fermentation of the engineered E. coli was conducted in a 5 L bioreactor. Subsequently, the conditions for whole-cell biocatalysis were optimized. The dry cell weight of the 4HPA3H-expressed strain reached 34.80 g/L. After incubated in the bioreactor for 6 h, 18.74 g/L (0.85 g/(L·OD₆₀₀)) of caffeic acid was obtained, with a conversion rate of 78.81% achieved. To the best of our knowledge, the titer of caffeic acid is the highest reported to date. The high-density fermentation of E. coli for overexpression of 4HPA3H and the efficient biosynthesis of caffeic acid may facilitate future large-scale production of caffeic acid.
Caffeic Acids ; Escherichia coli/metabolism* ; Fermentation ; Metabolic Engineering ; Mixed Function Oxygenases/metabolism* ; Phenylacetates

To study the chemical constituents of Ardisia punctata, compounds were isolated with a combination of multi-chromatography. Their structures were determined on the basis of spectral analysis and comparison to those of the known compounds. A 1,4-benzoquinone derivative and a alkylphenol were isolated from the petroleum ether extract of the roots of Ardisia punctata. Their structures were elucidated as 2-tridecyl-3-[(2-tridecyl-4-acetoxy-6-methoxy)-phenoxyl] -6-methoxy-1,4-benzoquinone (1) and 2-methoxy-4-hydroxy-6-tridecyl-phenyl acetate (2). The two compounds are both new.
Ardisia ; chemistry ; Benzoquinones ; chemistry ; isolation & purification ; Molecular Structure ; Phenylacetates ; chemistry ; isolation & purification ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry

During a continuing search for antimicrobial substances from Korean native wild mushroom extracts, we found that the methanolic extract of the fruiting body of Clitocybe nebularis exhibited mild antifungal activity against pathogenic fungi. Therefore we evaluated the antifungal substances and other chemical components of the fruiting body of Clitocybe nebularis, which led to the isolation of nebularine, phenylacetic acid, purine, uridine, adenine, uracil, benzoic acid, and mannitol. Nebularine showed mild antifungal activity against Magnaphorthe grisea and Trichophyton mentagrophytes, and phenylacetic acid potently inhibited the growth of Pythium ultiumand displayed moderate antifungal activity against Magnaphorthe grisea, Botrytis cinerea, and Trichophyton mentagrophytes. The other isolated compounds showed no antimicrobial activity.
Adenine ; Agaricales ; Benzoic Acid ; Botrytis ; Fruit ; Fungi ; Mannitol ; Methanol ; Phenylacetates ; Purine Nucleosides ; Purines ; Pythium ; Ribonucleosides ; Trichophyton ; Uracil ; Uridine

PURPOSE: Sodium-4-phenylbutyrate (Na-4-PB) is an analogue of phenylacetate, which is a well-known redifferentiating agent. In vitro and in vivo studies on this agent have been done and the clinical relevance of Na-4-PB has been studied in other malignancies, but not in thyroid cancer. We investigated the effect of Na-4-PB on cell proliferation and differentiation in thyroid cancer cell lines. METHODS: We used 5 thyroid cancer cell lines: TPC-1, FTC-133, FTC-236, FTC-238 and XTC-1. MTT assay and flowcytometry were used to measure the agent's antiproliferative effects and the cell cycle change. We evaluated the PPARgamma expression via western blotting and the mRNA expressions of NIS, Tg and CD 97 were determined by performing RT-PCR. Troglitazone, a potent PPARgamma agonist, was used in combined treatment with Na-4-PB. RESULTS: Na-4-PB inhibited cell proliferation in a dose and time dependent manner in all 5 thyroid cancer cell lines. By performing flowcytometry in the FTC-133 and TPC-1 cell lines, we identified that the antiproliferative effect of Na-4-PB was associated with an increased apoptotic cell population. Treatment with Na-4-PB upregulated the PPARgamma expression, but the combined treatment of Na-4-PB with troglitazone did not seem to be synergistic for the antiproliferative effect. Treatment with Na-4-PB downregulated the CD97 mRNA expression and it upregulated the NIS and Tg mRNA expressions in both the FTC-133 and TPC-1 cell lines. CONCLUSION: Na-4-PB inhibited thyroid cancer cell proliferation by inducing apoptosis in a dose dependent manner. Treatment with Na-4-PB increased the expression of PPARgamma and it upregulated such differentiation markers as NIS and Tg, and it downregulated CD97, a dedifferentiation marker. Na-4-PB should be further evaluated as a new potential therapeutic agent for patients with thyroid cancer.
Antigens, Differentiation ; Apoptosis ; Blotting, Western ; Cell Cycle ; Cell Line ; Cell Proliferation ; Chromans ; Histone Deacetylase Inhibitors ; Humans ; Phenylacetates ; PPAR gamma ; RNA, Messenger ; Thiazolidinediones ; Thyroid Gland ; Thyroid Neoplasms

The correlation of serum arylesterase (PON1) activity on phenylacetate determined by an integrated method to classical biochemical indexes of liver damage was investigated for the use of PON1 activity to evaluate liver damage. PON1 reaction curve as absorbance at 270 nm for 0.20 mmol/L phenylacetate hydrolysis was analyzed by the integrated method to determine maximal PON1 reaction rate. Classical biochemical indexes of liver damage were determined routinely. The 95% confidence threshold of PON1 activity in sera from healthy individuals was 2.12 mkat/L [(4.73+/-1.31) mkat/L, n=105]. PON1 activity in clinical sera was closely correlated to serum albumin, total protein and the ratio of albumin to globulins, but was weakly correlated to both direct and total bilirubin in serum. There were no correlations of PON1 activity to gamma-glutamyltransferase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. Among 127 clinical sera with PON1 activity>2.12 mkat/L, there were 92% healthy individuals examined by albumin, 90% healthy individuals examined by total protein, 88% healthy individuals examined by total bilirubin, 86% healthy individuals examined by direct bilirubin and 64% healthy individuals examined by the ratio of albumin to globulins, respectively. In each group of healthy individuals judged by classical biochemical indexes of close correlation to PON1 activity, percentage of healthy individuals examined by PON1 activity was always >80%. These results suggested PON1 activity on phenylacetate estimated by the integrated method was also suitable for the evaluation of liver damage.
Alanine Transaminase ; blood ; Aryldialkylphosphatase ; blood ; Aspartate Aminotransferases ; blood ; Biomarkers ; Carboxylic Ester Hydrolases ; blood ; Clinical Laboratory Techniques ; Humans ; Liver Diseases ; blood ; enzymology ; Liver Function Tests ; Phenylacetates

AIM: To study the chemical constituents from the fermentation of the endophytic fungus HP-1 of Chinese eaglewood. METHODS: The chemical constituents were isolated by column chromatography on silica gel and Sephadex LH-20, and their structures were elucidated on the basis of spectroscopic analysis. RESULTS: Four compounds were isolated and identified as 3α, 3β, 10β-trimethyl-decahydroazuleno[6, 7]furan-8, 9, 14-triol (1), 4-hydroxyphenylacetic acid (2), 4-hydroxyphenethyl alcohol (3), and 5-hydroxymethyl-2-furancarboxaldehyde (4). CONCLUSION Compound 1 was a new compound. Compound 2 showed antibacterial activity against Staphylococcus aureus.
Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Endophytes ; chemistry ; Fungi ; chemistry ; Phenylacetates ; chemistry ; isolation & purification ; pharmacology ; Sesquiterpenes ; chemistry ; isolation & purification ; Thymelaeaceae ; microbiology ; Wood ; microbiology

The goal of this study was to determine whether gypenosides (GPS) exert protective effects against dopaminergic neuronal cell death in a 6-hydroxydopamine (OHDA)-lesioned rat model of Parkinson's disease (PD) with or without long-term 3,4-dihydroxyphenylalanine (L-DOPA) treatment. Rats were injected with 6-OHDA in the substantia nigra to induce PD-like symptoms; 14 days after injection, groups of 6-OHDA-lesioned animals were treated for 21 days with GPS (25 or 50 mg/kg) and/or L-DOPA (20 mg/kg). Dopaminergic neuronal cell death was assessed by counting tyrosine hydroxylase (TH)-immunopositive cells in the substantia nigra and measuring levels of dopamine, norepinephrine, 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in the striatum. Dopaminergic neuronal cell death induced by 6-OHDA lesions was ameliorated by GPS treatment (50 mg/kg). L-DOPA treatment exacerbated 6-OHDA-induced dopaminergic neuronal cell death; however, these effects were partially reversed by GPS treatment (25 and 50 mg/kg). These results suggest that GPS treatment is protective against dopaminergic neuronal cell death in a 6-OHDA-lesioned rat model of PD with long-term L-DOPA treatment. Therefore, GPS may be useful as a phytotherapeutic agent for the treatment of PD.
3,4-Dihydroxyphenylacetic Acid ; Animals ; Cell Death* ; Dihydroxyphenylalanine ; Dopamine ; Dopaminergic Neurons* ; Homovanillic Acid ; Levodopa* ; Models, Animal* ; Norepinephrine ; Oxidopamine ; Parkinson Disease* ; Rats* ; Substantia Nigra ; Tyrosine 3-Monooxygenase

In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus in vivo, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE 0.17 +/- 0.01, 3,4-dihydroxyphenylacetic acid (DOPAC) 0.94 +/- 0.07, homovanillic acid (HVA) 0.57 +/- 0.05 pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine (50microM) enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.
3,4-Dihydroxyphenylacetic Acid ; Animals ; Brain* ; Chromatography, Liquid ; Dialysis Solutions ; Homovanillic Acid ; Hypothalamus ; Hypothalamus, Posterior* ; Imipramine ; Microdialysis* ; Monoamine Oxidase Inhibitors ; Neurons ; Neurotransmitter Agents ; Norepinephrine* ; Pargyline ; Potassium ; Rats*

OBJECTIVEEven though phenylacetate (PA) bas been shown to inhibit the growth and induce differentiation in rat C6 glioma cell line, its mechanisms are still poorly understood. This study is aimed to identify which Hox gene is related to glioma and to observe the change in expression on mRNA level as treated by phenylasetate.

METHODSTwenty-two kinds of Hox gene were divided into 3 groups according to their primer sequence. Semiquantitative reverse transcription- polymerase chain reaction (RT-PCR) was used to investigate the mRNA expression of Hox gene groups and some Hox gene in rat C6 glioma cell line following differentiation induced by PA. The level of Hox gene expression was expressed as ratio expression rate (RER) of Hox gene/beta-actin according to computer image analysis and the difference between C6 cells and PA treated C6 cells was analyzed by student t-test.

RESULTSIt was found that Hox genes matching to primers P2 were mildly expressed in C6 cells and the expression of HoxB2 mRNA was significantly up-regulated in PA treated C6 cells (P < 0.001).

CONCLUSIONThe weak expression of HoxB2 may be involved in glioma origin and the mechanisms of PA action are correlated with transcription process in the glioma cells.

Animals ; Antimetabolites, Antineoplastic ; pharmacology ; Gene Expression Regulation, Neoplastic ; drug effects ; Genes, Homeobox ; genetics ; Glioma ; genetics ; pathology ; Phenylacetates ; pharmacology ; RNA, Messenger ; drug effects ; genetics ; metabolism ; Rats ; Tumor Cells, Cultured ; Up-Regulation ; drug effects

OBJECTIVETo investigate the effects of CDA-II alone or combined with cAMP on the retinoic acid (RA)-resistant acute promyelocytic leukemia (APL) cells.

METHODSThe RA-resistant cell line NB4-R2 was used as an in vitro model and treated with CDA-II alone or in combination with cAMP. Cell apoptosis was assessed by morphology observation, distribution of cellular DNA contents and sub-G1 cell population. The level of Bcl-2 was detected by flow cytometry, DNA "ladder" was detected by agarose-electrophoresis.

RESULTSCDA-II could induce NB4-R2 cell apoptosis through decreasing the level of cellular anti-apoptotic protein Bcl-2. cAMP could significantly enhance the role of CDA-II. Bcl-2 positive cell rates decreased to (15.1 +/- 4.8)% and (7.3 +/- 2.9)% in NB4-R2 cells treated with 1 mg/ml CDA-II plus 100 micromol/L cAMP for 48 h and 72 h, respectively. While 100 micromol/L of cAMP could decrease Bcl-2 positive NB4-R2 cells from (92.0 +/- 0.6)% to (75.3 +/- 2.0)%.

CONCLUSIONSCDA-II combined with cAMP could exert potent apoptotic effect on RA-resistant APL cells.

Animals ; Apoptosis ; drug effects ; CD11c Antigen ; metabolism ; Cells, Cultured ; Cyclic AMP ; pharmacology ; Humans ; Leukemia, Promyelocytic, Acute ; drug therapy ; pathology ; Peptides ; pharmacology ; Phenylacetates ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Tretinoin ; pharmacology