Polymalic acid, known as a bioactive material, is completely biodegradable, and has far reaching application potential in medical field. Combined with our own findings, we summarized advances in polymalic acid metabolism, microbial fermentation synthesis, and application research in the medical field. Finally, prospect for further research was addressed.
Fermentation ; Industrial Microbiology ; Malates ; chemistry ; Polymers ; chemistry

OBJECTIVETo isolate and identify the high-yield poly-malic acid (PMLA) bacterial strains from the nature.

METHODSSamples were collected and cultured. The high-yield PMLA bacterial strains were screened through morphological observation, qualitative PMLA tests by HPLC and ITS sequence analysis on the isolated bacterial strains.

RESULTSA high-yield PMLA strain II 04 was isolated, the yield of PMLA of the strain reached to 26.23g/L in the rotary shaker at 25 degree for 7d. From morphological observation and ITS sequences analysis, the strain belonged to Aureobasidium pullulans, and named as Aureobasidium pullulans ZUCC-41.

CONCLUSIONA high-yield bacterial strain has been isolated from the nature and identified to be Aureobasidium pullulans.

Fermentation ; Malates ; metabolism ; Mitosporic Fungi ; isolation & purification ; metabolism ; Polymers ; metabolism

To develop a genetic transformation method of Aureobasidium pullulans and T-DNA insertion for high-efficient screening of polymalic acid (PMA) producing strain. Agrobacterium tumefaciens-AGL1, containing the selection genes encoding hygromycin B phosphotase or phosphinothricin acetyltranferase, was used to transform Aureobasidium pullulans CCTCC M2012223 and transformants were confirmed by colony PCR method. Transferred DNA (T-DNA) insertional mutants were cultured in microwell plate, and screened for high-titer PMA producing strain according to the pH response model. DNA walking was used to detect the insertion sites in the mutant. Results show that the selection markers could stably generated in the transformants, and 80 to 120 transformants could be found per 10(7) single cells. A high-titer PMA mutant H27 was obtained, giving a good PMA production caused by the disruption of phosphoglycerate mutase, that increased by 24.5% compared with the control. Agrobacterium tumefaciens-mediated transformation and high-efficient screening method were successfully developed, which will be helpful for genetic transformation of Aureobasidium pullulans and its functional genes discovery.
Agrobacterium tumefaciens ; Ascomycota ; genetics ; metabolism ; DNA, Bacterial ; Malates ; metabolism ; Polymerase Chain Reaction ; Polymers ; metabolism ; Transformation, Genetic

In an effort to develop novel mushroom-derived anti-obesity nutraceuticals, water and ethanol extracts containing the lipaseinhibitory compound from Phellinus linteus were prepared, and their nutritional components were determined. The optimal conditions for the extraction of P. linteus lipase inhibitor involved the treatment of the fruiting bodies with distilled water at 80degrees C for 72 hr and 80% ethanol at 100degrees C for 60 hr, respectively. The distilled water extract and ethanol extract contained 10.9% and 6.11% of crude protein, and 0.96% and 15.86% of crude fat, respectively. Additionally, the distilled water extract contained a large quantity of minerals, including 239.5 mg of K, 39.3 mg of Mg, and 39.3 mg of Na. The free amino acid content of the distilled water extracts was also higher than that of the ethanol extracts, and in particular, the distilled water extracts contained 5,139 mg of asparagine, 3,891 mg of tryptophan, 2,598 mg of alanine, and 2,066 mg of serine in 100 g of the distilled water extracts. 100 g of the distilled water and ethanol extracts were found to contain 12.31 g and 8.16 g of malic acid, respectively.
Alanine ; Asparagine ; Dietary Supplements ; Ethanol ; Fruit ; Lipase ; Malates ; Minerals ; Serine ; Tryptophan ; Water

The present study isolated 17 compounds from the tubers of Bletilla striata (Orchidaceae), using various chromatographic techniques. Their structures were identified based on their physical-chemical properties and spectroscopic analyses. Among them, two new 2-isobutylmalates, named bletimalates A (1) and B (2), together with other fifteen known compounds (3-17), were isolated and identified. Additionally, compounds 3, 4, and 8 were isolated from this plant for the first time.
Malates ; chemistry ; isolation & purification ; Molecular Structure ; Orchidaceae ; chemistry ; Plant Extracts ; chemistry ; isolation & purification ; Plant Tubers ; chemistry

Citric Acid Cycle ; Citric Acid ; Malates/metabolism* ; Citrates/metabolism* ; Aspartic Acid/metabolism*

In this study, we prepared various matrices of hydrogel patches and studied their cross-linking mechanism by observing their rheological properties, which could provide theoretical basis and deep technical support for further industrial development of hydrogel patch. Rheology method was used to do the amplitude scanning and single-frequency scanning for various hydrogel matrix, under the condition of oscillation mode of the rheometer. Then the linear viscoelastic region, composite modulus value, as well as changes in slope with time of the composite modulus and phase angle of various hydrogel matrix were analyzed in detail. The results showed that the stability of matrix was mainly determined by hydrogel frame; only in acidic environment, the cross-linking reaction between cross-linker and hydrogel frame can occur; elasticity of matrix can be decreased by organic acid and the effect level was related to the ratio of the number of carboxyl and hydroxyl (-COO(-)/-OH) in adjusters: if the ratio was not equal, the higher -COO(-)/-OH in adjusters would be the less elasticity of matrix decreased; the cross-linking speed of matrix was determined by adjuster, the cross-linking speed of matrix contain different adjusters was ranged in following order: matrix containing tartaric acid > matrix containing lactic acid > matrix containing malic acid > matrix containing citric acid; the cross-linking speed of matrix was not uniform in the whole cross-linking process.
Citric Acid ; chemistry ; Cross-Linking Reagents ; chemistry ; Hydrogels ; chemistry ; Lactic Acid ; chemistry ; Malates ; chemistry ; Rheology ; Tartrates ; chemistry ; Viscosity

OBJECTIVETo study the different and the variety of four organic acids in leaves of Isatis indigotica among different cultivated populations in water stress condition and healthy plant.

METHODFour kinds of organic acids, such as oxalic acid, malic acid, ascorbic acid and citric acid from the leaves, were detected by HPLC.

RESULTSignificant differences of four organic acids in the leaves of Beijing, Mongolia, Hebei and Shanxi cultivated populations. Compared with the healthy plant, the content of oxalic acid, malic acid and citric acid in water stress were increased, while the content of ascorbic acid was decreased.

CONCLUSIONContents of four organic acids can act as the guideline factor in I. indigotica because they were related with the water stress condition.

Ascorbic Acid ; chemistry ; metabolism ; China ; Chromatography, High Pressure Liquid ; Citric Acid ; chemistry ; metabolism ; Dehydration ; Isatis ; chemistry ; metabolism ; Malates ; chemistry ; metabolism ; Oxalic Acid ; chemistry ; metabolism ; Plant Leaves ; chemistry ; metabolism

Ten glucosyloxybenzyl 2-isobutylmalates and one benzyl alcohol glycoside were isolated from the dry tuber of Pleione bulbocodioides, which is a specie of Orchidaceae family and its dry tuber is one of the main sources of traditional Chinese medicine "shanci-gu", by a combination of various column chromatographic methods, including ODS, macroporous adsorbent resin, Sepheadex LH-20, and preparative HPLC. Their structures were identified on the basis of chemical evidences and spectroscopic analysis asloroglossin (1), grammatophylloside A (2), cronupapine (3), (-)-(2R, 3S)-1-(4-β-D-glucopyranosyloxybenzyl)-4-methyl-2-isobutyltartrate (4), vandateroside II (5), grammatophylloside B (6), bis [4-(β-D-glucopyranosyloxy) -benzyl] (S) -2-isopropylmalate (7), gymnoside I (8), militarine (9), dactylorhin A (10), gastrodin (11). Compounds 1-7 were isolated from this genus for the firt time.
Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Glucosides ; chemistry ; isolation & purification ; Malates ; chemistry ; isolation & purification ; Molecular Structure ; Orchidaceae ; chemistry ; Spectrometry, Mass, Electrospray Ionization

OBJECTIVETo compare and analyze the organic acids level in fruit of Crataegus pinnatifida var. major before and after processing.

METHODThe amount of total organic acids and individual citric acid, malate acid, ursolic acid and oleanolic acid in fruit of C. pinnatifida var. major before and after processing were determined by pH titration and HPLC analysis.

RESULTGood linear relationship between peakarea and amount was noted for 0.28-9.02 microg of malate acid, with a correlation coefficient of 0.9998. Regression equation was Y = 2344.7 + 49309.6 X. Good linear relationships between the logarithm of peak area and amount were noted for 0.348-1.74 microg of usolic acid and 0.498-2.48 microg of oleanolic acid, with a correlation coefficient of 0.9998 in each case. Regression equations were Y = 1.3628 X + 5.9508 and Y = 1.4447 X + 5.8236, respectively.

CONCLUSIONThe lipid-soluble organic acids mostly remain whereas only about 70% of the water-soluble acids remain after processing in fruit of C. pinnatifida var. major.

Citric Acid ; analysis ; Crataegus ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Fruit ; chemistry ; Hot Temperature ; Malates ; analysis ; Oleanolic Acid ; analysis ; Plants, Medicinal ; chemistry ; Technology, Pharmaceutical ; Triterpenes ; analysis