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2.
Front Neurol ; 14: 1097686, 2023.
Article in English | MEDLINE | ID: mdl-37006494

ABSTRACT

Objective: To explore the influence of the type of anterior clinoidal meningioma on surgical strategy planning, surgical approach selection, and postoperative efficacy. Patients and methods: We conducted a retrospective analysis of the clinical data of 63 cases, including data on visual function, extent of tumor resection, and postoperative follow-up. Grade I and II approaches were selected according to the type of tumor. A univariate analysis of the factors influencing the extent of tumor resection, postoperative visual function, and postoperative relapse and complications was conducted. Results: Simpson Grade I-II total resection was seen in 48 cases (76.2%), with an overall relapse/progression rate of 12.7%. The tumor type and texture and the relationship between the tumors and adjacent structures were the main factors influencing total tumor resection (P < 0.01). The overall postoperative visual acuity improvement, stabilization rate, and deterioration rate were 76.2, 15.9, and 7.9%, respectively. Postoperative visual acuity level was significantly correlated with preoperative visual acuity level and tumor type (P < 0.01). Conclusions: Determining the type of tumor at a preoperative level and whether the optic canal and cavernous sinus are invaded can aid in the planning of detailed individualized surgical strategies.

3.
Biotechnol Lett ; 38(3): 425-34, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26543036

ABSTRACT

OBJECTIVES: Efficient enzymatic saccharification of plant cell wall material is key to industrial processing of agricultural and forestry waste such as straw and wood chips into fuels and chemicals. RESULTS: Saccharification assays were performed on steam-pretreated wheat straw under ambient and O2-deprived environments and in the absence and presence of a lytic polysaccharide monooxygenase (LPMO) and catalase. A kinetic model was used to calculate catalytic rate and first-order inactivation rate constants of the cellulases from reaction progress curves. The addition of a LPMO significantly (P < 0.01, Student's T test) enhanced the rate of glucose release from 2.8 to 6.9 h(-1) under ambient O2 conditions. However, this also significantly (P < 0.01, Student's T test) increased the rate of inactivation of the enzyme mixture, thereby reducing the performance half-life from 65 to 35 h. Decreasing O2 levels or, strikingly, the addition of catalase significantly reduced (P < 0.01, Student's T test) enzyme inactivation and, as a consequence, higher efficiency of the cellulolytic enzyme cocktail was achieved. CONCLUSION: Oxidative inactivation of commercial cellulase mixtures is a significant factor influencing the overall saccharification efficiency and the addition of catalase can be used to protect these mixtures from inactivation.


Subject(s)
Catalase/metabolism , Glucose/metabolism , Lignin/metabolism , Mixed Function Oxygenases/metabolism , Cellulases/metabolism , Kinetics , Oxidation-Reduction , Plant Stems/metabolism , Triticum/metabolism
4.
Magn Reson Chem ; 50(1): 79-83, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22328449

ABSTRACT

Five new glucosylated steroidal glycosides, cantalasaponin I-B(1) (1), I-B(2) (2), I-B(3) (3), I-B(4) (4) and I-B(5) (5), were isolated and purified from the transformed product of the cantalasaponin I by using Toruzyme 3.0 l as biocatalyst. Their structures were elucidated on the basis of high-resolution electrospray ionization mass spectrometry, one-dimensional ((1) H and (13) C NMR) and two-dimensional [COSY, heteronuclear single-quantum correlation (HSQC), HMBC and HSQC-TOCSY] NMR spectral analyses and chemical evidence.


Subject(s)
Saponins/chemistry , Biocatalysis , Glucosyltransferases/chemistry , Glucosyltransferases/metabolism , Glycosylation , Magnetic Resonance Spectroscopy/standards , Molecular Structure , Reference Standards , Saponins/isolation & purification , Saponins/metabolism
5.
J Asian Nat Prod Res ; 12(11): 955-61, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21061217

ABSTRACT

Timosaponin BII (1), a steroidal saponin showing potential anti-dementia activity, was regioselectively hydrolyzed into its deglycosyl derivatives by the crude enzyme from Aspergillus niger AS 3.0739. Three biotransformation products, timosaponin BII-a (2), timosaponin BII-b (3), and timosaponin BII-c (4), were purified and their structures were elucidated on the basis of 1D NMR, 2D NMR, FAB-MS, and HR-ESI-MS spectral data. Compounds 2 and 3 are new compounds.


Subject(s)
Aspergillus niger/enzymology , Saponins/metabolism , Steroids/metabolism , Biotransformation , Dementia/drug therapy , Hydrolysis , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Saponins/chemistry , Saponins/pharmacology , Stereoisomerism , Steroids/chemistry , Steroids/pharmacology
6.
Carbohydr Res ; 345(12): 1752-9, 2010 Aug 16.
Article in English | MEDLINE | ID: mdl-20579977

ABSTRACT

Timosaponin BII (BII), a steroidal saponin showing potential anti-dementia activity, was converted into its glucosylation derivatives by Toruzyme 3.0L. Nine products with different degrees of glucosylation were purified and their structures were elucidated on the basis of (13)C NMR, HR-ESI-MS, and FAB-MS spectra data. The active enzyme in Toruzyme 3.0L was purified to electrophoretic homogeneity by tracking BII-glycosylase activity and was identified as Cyclodextrin-glycosyltransferase (CGTase, EC 2.4.1.19) by ESI-Q-TOF MS/MS. In this work, we found that the active enzyme catalyzed the synthesis of alpha-(1-->4)-linked glucosyl-BII when dextrin instead of an expensive activated sugar was used as the donor and showed a high thermal tolerance with the most favorable enzymatic activity at 100 degrees C. In addition, we also found that the alpha-amylases and CGTase, that is, GH13 family enzymes, all exhibited similar activities, which were able to catalyze glucosylation in steroidal saponins. But other kinds of amylases, such as gamma-amylase (GH15 family), had no such activity under the same reaction conditions.


Subject(s)
Biocatalysis , Glucosyltransferases/metabolism , Saponins/metabolism , Steroids/metabolism , Carbohydrate Sequence , Enzyme Activation , Glucosyltransferases/chemistry , Glycosylation , Hydrogen-Ion Concentration , Molecular Conformation , Saponins/chemistry , Stereoisomerism , Steroids/chemistry , Temperature , Time Factors
7.
Planta Med ; 76(15): 1724-31, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20486072

ABSTRACT

It is known that the sugar chains of steroidal saponins play an important role in the biological and pharmacological activities. In order to synthesize steroidal saponins with novel sugar chains in one step for further studies on pharmacological activity, we here describe the glucosylation of steroidal saponins, and 5 compounds, timosaponin AIII (1), saponin Ta (2), saponin Tb (3), trillin (4) and cantalasaponin I (5), were converted into their glucosylated products by Toruzyme 3.0 L, a cyclodextrin glucanotransferase (CGTase). 12 glucosylated products were isolated and their structures elucidated on the basis of spectral data; they were all characterized as new compounds. The results showed that Toruzyme 3.0 L had the specific ability to add the α-D-glucopyranosyl group to the glucosyl group linked at the sugar chains of steroidal saponins, and the glucosyl group was the only acceptor. This is the first report of steroidal saponins with different degrees of glucosylation. The substrates and their glucosylated derivatives were evaluated for their cytotoxicity against HL-60 human promyelocytic leukemia cell by MTT assay. The substrates all exhibited high cytotoxicity (IC(50) < 10 µmol/L), excluding compound 5 (IC(50) > 150 µmol/L), and the cytotoxicity of most of the products showed no obvious changes compared with those of their substrates.


Subject(s)
Glucosyltransferases/chemistry , Saponins/chemistry , Agave/chemistry , Anemarrhena/chemistry , Cytotoxins/pharmacology , HL-60 Cells , Humans , Magnoliopsida/chemistry , Saponins/isolation & purification , Saponins/pharmacology , Substrate Specificity
8.
J Asian Nat Prod Res ; 10(5-6): 463-6, 2008.
Article in English | MEDLINE | ID: mdl-18464088

ABSTRACT

A new triterpenoid compound (1) and a known compound (2) were isolated from the product of biotransformation of glycyrrhizic acid by Aspergillus niger. On the basis of the 1D and 2D NMR ((1)H-(1)H COSY, HSQC, HMBC and NOESY) and MS spectrometry, their structures were established as 7beta, 15alpha-dihydroxy-3,11-dioxo-oleana-12-en-30-oic acid (1) and 15alpha-hydroxy-3,11-dione-oleana-12-en-30-oic acid (2), respectively.


Subject(s)
Glycyrrhizic Acid/analogs & derivatives , Triterpenes/isolation & purification , Aspergillus niger/metabolism , Biotransformation , Glycyrrhiza/chemistry , Glycyrrhizic Acid/metabolism , Magnetic Resonance Spectroscopy , Molecular Structure , Triterpenes/chemistry
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