1.A new isoflavone from Dalbergia odorifera and inhibitory activity of its tyrosinase.
Suet CHEUNG ; Wan FANG ; Xiao-Qing LI ; Rui WANG ; Shi-Kai YAN ; Hui-Zi JIN
China Journal of Chinese Materia Medica 2022;47(18):4959-4965
Twelve flavonoids were isolated and purified from the ethyl acetate fraction of 95% ethanol extract of Dalbergia odorifera by heat reflux extraction, solvent extraction, recrystallization, normal phase silica gel, Sephadex LH-20, MCI gel and HPLC methods. The structures were identified with multiple spectroscopic methods, including 1 D-NMR, 2 D-NMR and MS. The compounds were identified as 6,7,8-trimethoxy-5,4'-dihydroxy isoflavone(1), medicarpin(2), 7,2'-dihydroxy-4'-methoxy-isoflavanol(3), biochanin A(4), prunetin(5), genistein(6), pratensein(7), 3-(4-hydroxyphenyl)-6-isopentenyl-7-methoxy-4H-chromen-4-one(8), tectorigenin(9), irisolidone(10), vestitol(11), and formononetin(12). Compound 1 was a new isoflavone, and compound 8 was isolated from D. odorifera for the first time. The results showed that compounds 1-3 had inhibitory effects on tyrosinase, with inhibition rates of 35.58%, 38.63% and 51.34% at the concentration of 1.0 mmol·L~(-1), respectively.
Dalbergia/chemistry*
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Ethanol
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Flavonoids/chemistry*
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Genistein
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Isoflavones/pharmacology*
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Monophenol Monooxygenase
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Plant Extracts/pharmacology*
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Silica Gel
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Solvents
2.Improved cycle sequencing of GC-rich DNA template.
Jong Soon CHOI ; Jin Sung KIM ; Cheol O JOE ; Soo Hyun KIM ; Kwon Soo HA ; Young Mok PARK
Experimental & Molecular Medicine 1999;31(1):20-24
Even when DNA sequencing of purified DNA template failed under the optimal condition, it can be generally contributed to high GC content. GC-rich region of template causes a secondary structure to produce shorter readable sequence. To solve this problem, the sequencing reaction was modified by using dimethyl sulfoxide (DMSO). It was found that 5% (v/v) of DMSO in the reaction mixture recovers sequencing signal intensity with reduced frequency of ambiguous bases. When DMSO was added to sequencing reaction of DNA template with normal GC content, it did not show any adverse effect. Sequencing accuracy and unambiguous base frequency were significantly improved at concentration of 2% to 5% (v/v) DMSO in GC-rich DNA template. DMSO has been empirically introduced to enhance the efficiency of PCR in GC-rich templates. However, the underlying mechanism of improved cycle sequencing by DMSO is unknown. Thus, cycle sequencing reaction was remodified with other additives such as N-methyl imidazole, N-methyl2-pyrrolidone, N-methyl-2-pyridone and glycerol, possessing the similar chemical properties as DMSO. Most of methyl nitrogen ring-containing chemicals did not improve sequencing accuracy, whereas only glycerol mimicked the positive effect of DMSO by the same extent. In the present study, we suggest that the treatment of DMSO improve cycle sequencing by the alteration of structural conformation of GC-rich DNA template.
Base Composition
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DNA/chemistry*
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Dimethyl Sulfoxide/pharmacology*
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Plasmids/genetics
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Polymerase Chain Reaction/methods*
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Sequence Analysis, DNA*
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Solvents/pharmacology
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Solvents/chemistry
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Templates
3.Effects of residual water on microtensile bond strength of one-bottle dentin adhesive systems with different solvent bases.
Zhi-xing ZHANG ; Cui HUANG ; Tie-li ZHENG ; Sa WANG ; Xiang-rong CHENG
Chinese Medical Journal 2005;118(19):1623-1628
BACKGROUNDThe wet-bonding technique is recommended for the one-bottle dentin adhesive systems, but the moisture concept varies widely among the instructions of manufacturers as well as among investigators. The aim of this study was to evaluate the effects of different dentin surface moisture on the microtensile bond strength(s) of an ethanol/water-based adhesive system and an acetone-based system to dentin.
METHODSForty intact human premolars extracted for orthodontic reasons were used. Superficial occlusal flat dentin surfaces of these premolars were exposed, finished with wet 600-grit silicon carbide paper. Under four wet and dry conditions (overwet, blot dry, one-second dry and desiccated), resin composite was bonded to dentin by using Single Bond (SB) or Prime & Bond NT (PB) according to the manufacturers' instructions. The teeth were longitudinally sectioned in the "x" and "y" directions to obtain bonded beams with a cross-sectional area of 0.81 mm(2) with a slow-speed diamond saw. The bonded specimens were tested in tension at a crosshead speed of 1 mm/min until failure of the bonds. Failure modes were observed with a scanning electron microscope. The mean bond strengths were analyzed by one-way ANOVA and Turkey's test.
RESULTSThe bond strength of the overwet/SB, blot dry/SB, one-second dry/SB and desiccated/SB groups was 10.87 MPa, 22.47 MPa, 24.91 MPa and 12.99 MPa, respectively. The bond strength of the overwet/PB, blot dry/PB, one-second dry/PB and desiccated/PB groups was 10.02 MPa, 20.67 MPa, 21.82 MPa and 10.09 MPa, respectively. For both SB and PB, the blot dry group and one-second dry group revealed significantly higher bond strengths than the overwet and desiccated groups (P < 0.05).
CONCLUSIONSIn order to achieve the highest bond strength to dentin, keeping the dentin surface in an appropriately moist condition is critical for the one-bottle dentin adhesive systems with ethanol/water or acetone solvent.
Adolescent ; Adult ; Dental Bonding ; Dentin-Bonding Agents ; pharmacology ; Humans ; Solvents ; Tensile Strength ; Water
4.Tolerant mechanisms of bacteria to organic solvents.
Xinxin WANG ; Shaohua WANG ; Wei LI ; Yin LI ; Yanping ZHANG
Chinese Journal of Biotechnology 2009;25(5):641-649
Organic solvents are usually toxic to microorganisms for destroying the physiological functions. Recently, some studies have revealed that some bacteria are capable of living in conditions with high concentration of solvents through tolerant and adaptive mechanisms. This discovery inspires the research on adaptation and alteration of industrial bacteria, especially for those producing solvents or degrading toxic organic compounds. For a deep understanding and a wide application of the tolerant mechanisms, we address here the recent discoveries on solvents toxicity to bacteria by the parameter logP, and tolerant mechanisms of solvent-tolerant-bacteria to solvents, such as changes in cell membrane including cis-trans isomerisation, the saturated-to-unsaturated fatty acids ratio and the phospholipids head-groups, changes in outer membrane and cell morphology, and other stress responses. Moreover, our experiences in screening novel solvent-tolerant-bacteria and methods in increasing solvent tolerance of industrial microbes are introduced to give a promising strategy for improving solvent production.
Adaptation, Physiological
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drug effects
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Bacteria
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drug effects
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Drug Resistance, Bacterial
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drug effects
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Industrial Microbiology
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methods
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Organic Chemicals
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pharmacology
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Solvents
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pharmacology
5.Diuretic effect and material basis of Clematidis Armandii Caulis in rats.
Xiao YE ; Xuan-Xuan ZHU ; Ting LIU ; Xiao-Qian LIU ; Lian-Qiang HUI ; Wei-Hong FENG ; Li-Xin YANG ; Chun LI ; Zhi-Min WANG
China Journal of Chinese Materia Medica 2019;44(9):1889-1894
To search for the active diuretic fractions of Clematidis Armandii Caulis( CAC) and determine its main active chemical components by using liquid chromatography-mass spectrometry( LC-MS) and diuretic activity evaluation. CAC 75% ethanol extracts and extracts from different polar solvents were orally administered to saline-loaded rats at different doses. 6 h urinary volume,p H and contents of electrolyte Na+,K+and Cl-were measured. The chemical components of the active fractions were separated and identified by ultra performance liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry( UPLC-ESI-Q-TOF-MS/MS) method. As compared with the control group,the urine volume was increased by 44%( P< 0. 01) and 34%( P < 0. 05) in CAC75% ethanol extract 57. 74 and 28. 8 mg·kg-1 groups respectively; the Na+excretion was increased by 52%( P< 0. 01) and 45%( P<0. 05),respectively; while the Cl-excretion was increased by 101%( P<0. 01) and 85%( P<0. 05),respectively. The urine volume,Na+excretion and Cl-excretion were increased by 50%( P< 0. 01),58%( P< 0. 05),and 65%( P< 0. 05) respectively in petroleum ether extract 70. 98 mg·kg-1 group as compared with the control group. While for the n-butanol extract 194. 18 mg·kg-1 group,the urine volume,Na+and Cl-excretion were increased by 42%( P<0. 01),41%( P<0. 05) and 97%( P<0. 01),respectively. The diuretic activity of other fractions was not obvious. There was no statistical difference in K+excretion in all groups. The results of LC-MS analysis showed that six compounds,including two sterols,one chromogen and three fatty acids,were identified from petroleum ether extract.Fourteen compounds,including six triterpenoid saponins,six lignin glycosides,one sterol glycoside and one phenolic glycoside,were identified from the n-butanol extract. All the results suggested that the ethanol extract of CAC had remarkable diuretic activity and its main effective components included sterol,triterpenoid saponin and lignin glycosides.
Animals
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Ascomycota
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chemistry
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Diuretics
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pharmacology
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Materia Medica
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pharmacology
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Rats
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Solvents
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Spectrometry, Mass, Electrospray Ionization
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Tandem Mass Spectrometry
6.Catalysis of enzymes under industrial environment and their adaptive modifications: a review.
Wenhao WANG ; Pengfei WEN ; Kongliang XU ; Renchao ZHENG ; Yuguo ZHENG
Chinese Journal of Biotechnology 2019;35(10):1857-1869
Enzymes have a wide range of applications and great industrial potential. However, large-scale applications of enzymes are restricted by the harsh industrial environment, such as high temperature, strong acid/alkali, high salt, organic solvents, and high substrate concentration. Adaptive modification (such as rational or semi-rational design, directed evolution and immobilization) is the most common strategy to improve the catalysis of enzymes under industrial conditions. Here, we review the catalysis of enzymes in the industrial environment and various methods adopted for the adaptive modifications in recent years, to provide reference for the adaptive modifications of enzymes.
Biocatalysis
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drug effects
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Biotechnology
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Enzymes
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chemistry
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metabolism
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Hot Temperature
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Hydrogen-Ion Concentration
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Protein Engineering
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Solvents
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chemistry
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pharmacology
7.Lipase-catalyzed enantioselective ammonolysis of racemic phenylglycine methyl ester in organic solvent.
Wei DU ; Min-Hua ZONG ; Yong GUO ; Jun HE ; Yuan-Yuan ZHANG ; Zhao-Lin XIE ; Wen-Yong LOU
Chinese Journal of Biotechnology 2002;18(2):242-245
A novel reaction-enzymatic ammonolysis discovered in the mid of 1990s has been demonstrated to be a very promising alternative in the preparation of optically pure compounds. The effects of organic solvent, initial water activity, temperature and additives on lipase Novozym435-catalyzed enantioselective ammonolysis of racemic phenylglycine methyl ester were investigated systematically in this paper. Enzymatic reaction of ammonolysis showed higher activity and enantioselectivity than the corresponding reaction of hydrolysis and alcoholysis.
Alcohols
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Ammonia
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Catalysis
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Dimethylformamide
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pharmacology
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Esters
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Glycine
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analogs & derivatives
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metabolism
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Hexoses
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pharmacology
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Hydrolysis
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Lipase
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drug effects
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metabolism
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Organic Chemicals
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Solvents
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Surface-Active Agents
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pharmacology
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Temperature
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Water
8.Dormancy characteristics and breaking method of seeds from Epimedium wushanense.
Jiayi FAN ; Qiaosheng GUO ; Zuoyi LIU ; Guosheng ZHU ; Ning ZHOU ; Yong HE
China Journal of Chinese Materia Medica 2010;35(24):3242-3245
OBJECTIVETo research the mechanism of dormancy and find out the breaking method for the seeds of Epimedium wushanense.
METHODThe water permeability of seed coat was tested by weighing seeds. The germination inhibitor of the seeds were determined with biotic measurement. The development of embryos, germination rate and germination potential were determined after stratification.
RESULTThe water permeability of seed coat was 41.86% after 5 h. The extracts of seeds had strong inhibition effects to the length growth of cabbage seedlings. The growth and development of embryos under the cold stratification (5 degrees C) were better than that under the other conditions. The embryo rate extended from 15.39% to 86.21% after 90 d. Germination rate and germination potential after stratification under 5 degrees C were significantly higher than that under other temperatures.
CONCLUSIONThe results showed that there was no obstacle of water permeability on the test of E. wushanense, after-ripening of embryogenesis and the germination inhibitor of the seed were the main reason for the seed dormancy. The cold stratification would be an effective way for breaking of the dormancy, which could significantly promote the seed embryogenesis and increase germination rate comparing to other methods.
Epimedium ; drug effects ; growth & development ; physiology ; Plant Dormancy ; drug effects ; physiology ; Seeds ; drug effects ; growth & development ; physiology ; Solvents ; pharmacology ; Temperature ; Time Factors ; Water ; pharmacology
9.Effects of Basella alba and Hibiscus macranthus extracts on testosterone production of adult rat and bull Leydig cells.
Paul F MOUNDIPA ; Nathalie Sara E BEBOY ; Fabien ZELEFACK ; Silvére NGOUELA ; Etienne TSAMO ; Wolf-Bernhard SCHILL ; Thomas K MONSEES
Asian Journal of Andrology 2005;7(4):411-417
AIMTo determine the androgenic effects of Basella alba and Hibiscus macranthus extracts in the rat and the bull, and to develop a novel in vitro test system using Leydig cells from bull testes.
METHODSThe effect of methanol extracts from both plants on testosterone production in isolated Leydig cells from the rat and the bull was analyzed using 125I-radioimmunoassay (125I-RIA). Rat Leydig cells were obtained by common methods, whereas a novel technique was used to purify Leydig cells from bull testes.
RESULTSBull testes from the slaughter house were a cheap source of pure Leydig cells. In culture, these cells produced testosterone for 5-6 days, which can be stimulated by human chorionic gonadotrophin (hCG). Basella alba extracts significantly enhanced testosterone production in bull and rat Leydig cells in a concentration-dependent manner. Hibiscus macranthus showed no androgenic effect but was shown to inhibit testosterone production at higher concentrations.
CONCLUSIONLeydig cells purified from bull testes can be used as an alternative tool in experimental animal research. Certain fractions of Basella alba extract demonstrated androgenic potential whereas Hibiscus macranthus extracts did not.
Animals ; Cattle ; Cells, Cultured ; Hibiscus ; Iodine Radioisotopes ; Leydig Cells ; cytology ; drug effects ; metabolism ; Male ; Methanol ; Plant Extracts ; pharmacology ; Plants, Edible ; Rats ; Rats, Sprague-Dawley ; Solvents ; Testosterone ; biosynthesis
10.Antimicrobial potential of Ricinus communis leaf extracts in different solvents against pathogenic bacterial and fungal strains.
Asian Pacific Journal of Tropical Biomedicine 2012;2(12):944-947
OBJECTIVETo investigate the in vitro antimicrobial activities of the leaf extract in different solvents viz., methanol, ethanol and water extracts of the selected plant Ricinus communis.
METHODSAgar well diffusion method and agar tube dilution method were carried out to perform the antibacterial and antifungal activity of methanol, ethanol and aqueous extracts.
RESULTSMethanol leaf extracts were found to be more active against Gram positive bacteria (Bacillus subtilis: ATCC 6059 and Staphylococcus aureus: ATCC 6538) as well as Gram negative bacteria (Pseudomonas aeruginosa: ATCC 7221 and Klebsiella pneumoniae) than ethanol and aqueous leaf extracts. Antifungal activity of methanol and aqueous leaf extracts were also carried out against selected fungal strains as Aspergillus fumigatus and Aspergillus flavus. Methanolic as well as aqueous leaf extracts of Ricinus communis were effective in inhibiting the fungal growth.
CONCLUSIONSThe efficient antibacterial and antifungal activity of Ricinus communis from the present investigation revealed that the methanol leaf extracts of the selected plant have significant potential to inhibit the growth of pathogenic bacterial and fungal strains than ethanol and aqueous leaf extracts.
Anti-Bacterial Agents ; pharmacology ; Antifungal Agents ; pharmacology ; Aspergillus ; drug effects ; Gram-Negative Bacteria ; drug effects ; Gram-Positive Bacteria ; drug effects ; Humans ; Methanol ; chemistry ; Microbial Sensitivity Tests ; Plant Extracts ; pharmacology ; Plant Leaves ; chemistry ; Ricinus ; chemistry ; Solvents ; chemistry ; Water ; chemistry