OBJECTIVETo establish determination method of formic acid, lactic acid, acetic acid and succinic acid in dental plaque with high performance liquid chromatography (HPLC).

METHODSAfter the samples were centrifuged, 2 microL supernatant was transferred to a 1 mL centrifuge tube and diluted in water, then was determined with HPLC. The mixture of phosphate buffer and methanol (97:3) as mobile phase throughout the experiment. The determination of organic acid was performed on Phenomenex C18 column and at their maximum absorption wave.

RESULTSThe linear ranges of formic acid, lactic acid, acetic acid and succinic acid were 0.110-500, 0.049-500, 0.047-500, 0.084-500 microg/mL. The detection limits were 0.110, 0.049, 0.047, 0.084 microg/mL. The relative standard derivation were 9.5%, 7.9%, 4.3%, 4.2%. The average recoveries of samples were 82%-112%, 82%-102.5%, 90%-115%, 80%-110%.

CONCLUSIONThe method was simple, quick and adapt for analysis of organic acid in dental plaque.

Chromatography, High Pressure Liquid ; Dental Plaque ; Formates

The use of microbial cell factories to achieve efficient conversion of raw materials and synthesis of target substances is one of the important research directions of synthetic biology. Traditional industrial microorganisms have mainly used sugar-based raw materials as fermentation substrates. How to adopt cheaper carbon resources and realize their efficient use has been widely concerned. Formic acid is an important organic one-carbon source and widely used in industrial manufacturing of pesticides, leather, dyes, medicine and rubber. In recent years, due to the demand fluctuation in downstream industries, formic acid production is facing the dilemma of overcapacity, and therefore, requiring new conversion paths for expansion and extension of the related industrial chain. Biological route is one of the important options. However, natural formate-utilizing microorganisms generally grow slowly when metabolizing formic acid, and moreover, are difficult to be artificially modified by the absence of effective genetic tools. Construction of non-natural formate-utilizing microorganisms is another alternative strategy, but still in its infancy and has a huge space for further improvements. Here, we briefly summarize the recent research progress of biological utilization of formic acid, and also propose the future research focus and direction.
Fermentation ; Formates ; metabolism ; Industrial Microbiology ; trends ; Synthetic Biology ; trends

OBJECTIVETo study the methods of decalcification for making united slices of tooth and affiliated periodontic tissues.

METHODSTwenty-one samples containing dog molars and affiliated periodontic tissues were divided into seven mean groups. The pH value of solution, time of decalcification, weight and volume of samples, and content of decalcified calcium were detected. The slices were observed by HE, specific, and immunohistochemical stain.

RESULTSThe velocity of decalcification increased with decrease of solution pH. The weight of samples lightened by 37.61%, the volume reduced by 25.97% on average, and calcium decalcified was 174.49 mg per gram humid samples. The EDTA decalcification was slowest, but it was best. Decalcification was fast in Plank-Rycho solution while the section was worst, and faster in the formyl solution containing aluminium chloride than in EDTA, and the section was better.

CONCLUSIONSThe 50% formyl solution containing aluminium chloride is an ideal decalcifying solution.

Animals ; Decalcification Technique ; methods ; Dogs ; Edetic Acid ; Formates ; Microtomy ; Molar ; Periodontium

Now a days, people eat outside of the home more and more frequently. Menu labeling can help people make more informed decisions about the foods they eat and help them maintain a healthy diet. This study was conducted to develop menu labeling system using Nutri-API (Nutrition Analysis Application Programming Interface). This system offers convenient user interface and menu labeling information with printout format. This system provide useful functions such as new food/menu nutrients information, retrieval food semantic service, menu plan with subgroup and nutrient analysis informations and print format. This system provide nutritive values with nutrient information and ratio of 3 major energy nutrients. MLS system can analyze nutrients for menu and each subgroup. And MLS system can display nutrient comparisons with DRIs and % Daily Nutrient Values. And also this system provide 6 different menu labeling formate with nutrient information. Therefore it can be used by not only usual people but also dietitians and restaurant managers who take charge of making a menu and experts in the field of food and nutrition. It is expected that Menu Labeling System (MLS) can be useful of menu planning and nutrition education, nutrition counseling and expert meal management.
Counseling ; Diet ; Fees and Charges ; Formates ; Meals ; Menu Planning ; Nutritive Value ; Restaurants ; Semantics

An UPLC-Q-TOF-MS method was employed to characterize and classify the chemical components of the standard decoction of Yiguanjian, a classical famous recipe. Chromatographic separation was performed on an Acquity HSS T3(2.1 mm ×100 mm, 1.8 μm) column with a mobile phase of 0.1% formic acid water-0.1% formic acid acetonitrile using gradient elution. The flow rate was 0.4 mL·min~(-1) and the column temperature was 40 ℃. Mass spectrometry was performed on electrospray ionization source(ESI) with positive and negative ion scanning modes. The potential compounds were identified by comparing the reference compounds, analyzing the mass spectrometry data and matching the published articles on Masslynx 4.1 software and SciFinder database. Finally, a total of 113 compounds, including 11 amino acids, 19 terpenoids, 13 phthalides, 11 steroidal saponins, 10 coumarins, 9 alkaloids, 7 flavonoids, 8 phenylethanoid glycosides, 8 organic acids and 17 other categories were identified. The established method systematically and accurately characterized the chemical components in Yiguanjian, which could provide experimental evidences for the subsequent studies on the pharmacodynamical material basis and quality control of Yiguanjian.
Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal/chemistry* ; Flavonoids/analysis* ; Formates ; Glycosides/analysis* ; Prescriptions

Air ; analysis ; Air Pollutants, Occupational ; analysis ; Formates ; analysis ; Gas Chromatography-Mass Spectrometry ; methods ; Humans ; Occupational Exposure ; analysis ; Workplace

OBJECTIVETo study DNA damage of three kinds of gasoline oxygenates.

METHODSingle cell gel electrophoresis assay(Comet assay) was used to detect the damage effects of three gasoline oxygenates[methyl tertiary butyl ether(MTBE), ethanol anhydrous(EA) and dimethyl carbonate(DMC)] on DNA in L-929 mice fibroblasts.

RESULTSIn certain concentation(37.500-150.000 mg/ml), MTBE could directly cause DNA damage of L-929 mice fibroblasts. There was obvious dose-effect relationship, i.e. when the concentration of MTBE was increased from 9.375 to 150.000 mg/ml, the comet rate also increased from 4% to 85%, and the length of comet tail changed correspondingly. The results of EA and DMC were negative.

CONCLUSIONUnder the condition of this experiment(150.000 mg/ml), MTBE could directly cause DNA damage while the effect of EA and DMC on DNA damage was not found.

Animals ; Comet Assay ; DNA Damage ; Dose-Response Relationship, Drug ; Ethanol ; toxicity ; Fibroblasts ; drug effects ; Formates ; toxicity ; Methyl Ethers ; toxicity ; Mice

A qualitative analytical method of liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS) was developed for identification of multi-constituents and an analytical method was developed for simultaneously determining 4 major compounds (rutin, isoquercitrin, kaempferol-3-0-rutinoside, and astragalin) in Tetrastigma hemsleyanum Diels et Gilg. The HPLC-Q-TOF-MS assay was performed on a Welch Ultimate XB-C18 column (4.6 mm x 150 mm, 5 microm) with the mobile phase consisting of acetonitrile (A) and water containing 0.1% Formic acid (B) in gradient mode at a flow rate of 0.8 mL x min(-1). The column temperature was at 30 degrees C, and negative ion mode was used for TOF-MS. The UPLC-QqQ-MS assay was performed on a Waters CORTECS C18 (2.1 mm x 100 mm, 1.6 microm) with the mobile phase consisting of acetonitrile (A) and water containing 0.1% formic acid (B) in gradient mode at a flow rate of 0.25 mL x min(-1). The column temperature was at 45 degrees C, and MRM mode was used for QqQ-MS. Based on the retention time and MS spectra, 24 compounds were identified or tentatively characterized by comparing with reference substances or literatures. For quantitative the linear range of 4 detected compounds were good (r > 0.9966), and the overall recoveries ranged from 98.27% to 101.58%, with the RSD ranging from 3.15% to 5.88%. The results indicated that new approach conbined HPLC-Q-TOF-MS and UPLC-QqQ-MS was applicable in qualitative and quantitative quality control of Tetrastigma hemsleyanum.
Acetonitriles ; chemistry ; Chromatography, High Pressure Liquid ; methods ; Formates ; chemistry ; Tandem Mass Spectrometry ; methods ; Vitaceae ; chemistry ; Water ; chemistry

Aluminum Compounds ; pharmacology ; Animals ; Bone and Bones ; drug effects ; metabolism ; Chlorides ; pharmacology ; Decalcification Technique ; methods ; Formates ; chemistry ; Humans

This study was developed and validated for the determination of oxyclozanide residue concentrations in beef and commercial milk, using high-performance liquid chromatography system. Oxyclozanide was successfully separated on a reverse phase column (Xbridge-C18, 4.6x250 mm, 5 microm) with a mobile phase composed of acetonitrile and 0.1% phosphoric acid (60:40, v/v%). This analytical procedure involved a deproteinization process using acetonitrile for beef and 2% formic acid in acetonitrile for commercial milk, dehydration by adding sodium sulfate to the liquid analytical sample, and a defatting process using n-hexane; after these steps, the extract was exposed to a stream of nitrogen dryness. The final extracted sample was dissolved in the mobile phase and filtered using a 0.45 microm syringe filter. This method had good selectivity and recovery (70.70+/-7.90-110.79+/-14.95%) from the matrices. The LOQs ranged from 9.7 to 9.8 microg/kg for beef and commercial milk. The recoveries met the standards set by the CODEX guideline.
Acetonitriles ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Dehydration ; Formates ; Milk ; Nitrogen ; Oxyclozanide ; Phosphoric Acids ; Rivers ; Sodium ; Sulfates ; Syringes