排序方式: 共有49条查询结果,搜索用时 15 毫秒
21.
Francesca Sansone Alessandra Rossi Pasquale Del Gaudio Francesco De Simone Rita Patrizia Aquino Maria Rosaria Lauro 《AAPS PharmSciTech》2009,10(2):391-401
Gastroresistant microparticles for oral administration of hesperidin (Hd) were produced by spray-drying using cellulose acetate
phthalate (CAP) as enteric polymer in different polymer/Hd weight ratio (1:1, 3:1, and 5:1), and a series of enhancers of
the dissolution rate, such as sodium carboxymethylcellulose crosslinked (CMC), sodium dodecylbenzene sulfonate (SDBS), or
Tween85. The raw materials and the microparticles were investigated by differential-scanning calorimetry, X-ray diffraction,
infrared spectroscopy and imaged using scanning electron and fluorescence microscopy. In vitro dissolution tests were conducted using a pH-change method to investigate the influence of formulative parameters on the dissolution/release
properties of the drug. CAP/Hd microparticles showed a good gastro-resistance but incomplete drug dissolution in the simulated
intestinal fluid (SIF). The presence of the enhancers in the formulation produced well-formed microparticles with different
size and morphology, containing the drug well coated by the polymer. All the enhancers were able to increase the dissolution
rate of Hd in the simulated intestinal environment without altering CAP ability to protect Hd in the acidic fluid. The spray-drying
technique and process conditions selected were effective in microencapsulating and stabilizing the flavonoid giving satisfactory
encapsulation efficiency, product yield, and microparticles morphology, and a complete drug release in the intestine. 相似文献
22.
Elham Shakiba Ali Bazi Hamed Ghasemi Reza Eshaghi-Gorji Seyyed Alireza Mehdipour Banafsheh Nikfar Mohsen Rashidi Sepideh Mirzaei 《Journal of cellular and molecular medicine》2023,27(18):2756-2769
Considering the unfavourable response of breast cancer (BC) to treatment, we assessed the therapeutic potential hesperidin in mice bearing 4T1 BC tumours. Anti-tumour effects were assessed by measuring pathologic complete response (pCR), survival analysis, immunohistochemistry for E-cadherin, VEGF, MMP9, MMP2 and Ki-67, serum measurement of IFNγ and IL-4, and gene expression analysis of CD105, VEGFa, VEGFR2 and COX2. Survival of tumour-bearing mice was the highest in mice receiving a combination of hesperidin and doxorubicin (Dox) (80%) compared to the normal saline (43%), hesperidin 5 (54%), 10 (55.5%), 10 (60.5%) and 40 (66%) mg/kg, and 10 mg/kg Dox-treated (73%) groups (p < 0.0001 for all). Compared to the normal saline group, there was a significant elevation in IFNγ level in the animals receiving 20 (p = 0.0026) and 40 (p < 0.001) mg/kg hesperidin, 10 mg/kg Dox (p < 0.001), and combined hesperidin (20 mg/kg) and Dox (10 mg/kg) (p < 0.001). A significant reduction in the gene expression of CD 105 (p = 0.0106), VEGFa (p < 0.0001), VEGFR2 (p < 0.0001), and Cox2 (p = 0.034) and a significant higher pCR score (p = 0.006) were noticed in mice treated with 10 mg/kg Dox + 20 mg/kg hesperidin compared to those treated with 10 mg/kg Dox alone. Immunohistochemical staining showed significant reductions in Ki-67 (p < 0.001) and VEGF (p < 0.001) and a significant elevation in E-cadherin (p = 0.005) in the 10 mg/kg Dox + 20 mg/kg treatment group than in 10 mg/kg Dox alone group. Hesperidin can be considered as a potentially suitable anti-cancer agent for BC that can synergize with other chemotherapeutics. 相似文献
23.
Masami Kusunose Toshihiro Nakanishi Noshi Minamiura Takehiko Yamamoto 《Bioscience, biotechnology, and biochemistry》2013,77(12):2779-2784
Nearly all the amino group-producing activity of the autolysate of cells of Saccharomyces sake was recovered in the cell wall fraction obtained from the autolysis residue. The activity of the cell wall fraction was not lost even after repeated use.The proteolytic activity of the fraction was not solubilized by incubation with detergents, disruption with cell mill or by freezing and thawing method, but was solubilized to some extent by incubation with a commercial yeast cell-lytic enzyme preparation.The cell wall fraction hydrolysed casein to about 50%. When casein was previously treated with certain proteinases, more than 60% was digested. The activity of the fraction was significantly increased by the addition of Zn2+ while it was decreased by several proteolytic enzyme inhibitors. The interesting fact was that in the presence of EDTA the cell wall fraction showed only carboxypeptidase-like activity, and attacked the oxidized insulin B-chain to release two amino acids from the carboxyl terminal in known order. 相似文献
24.
Kanae Gamo Hiroyuki Miyachi Kayoko Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(6):1052-1059
In previous reports, hesperidin, a flavonoid glucoside from citrus fruit, is hydrolyzed to hesperetin, an aglycone of hesperidin, and converted to the hesperetin glucuronides (H7-OG and H3′-OG) in vivo and depresses blood glucose levels. But there are no reports on the activity of hesperetin glucuronides. To determine the activity of hesperetin glucuronides, H7-OG and H3′-OG were synthesized and peroxisome proliferator-activated receptor-γ (PPARγ) agonist activity was observed at 250?μM. These glucuronides accelerated the differentiation of 3T3-L1 cells into adipocytes at 10?μM. Furthermore, H7-OG showed additive effects in reporter gene assays and caused noncompetitive reactions in time-resolved fluorescence resonance energy transfer assays with a thiazolidinedione derivative. Our results indicated that hesperetin glucuronides activated PPARγ, accelerated adipocyte differentiation. 相似文献
25.
Fukamizo T Hayashi K Tamoi M Fujimura Y Kurotaki H Kulminskaya A Kitaoka M 《Archives of biochemistry and biophysics》2008,478(2):187-194
The specificity of 1,3-1,4-β-glucanase from Synechocystis PCC6803 (SsGlc) was investigated using novel substrates 1,3-1,4-β-glucosyl oligosaccharides, in which 1,3- and 1,4-linkages are located in various arrangements. After the enzymatic reaction, the reaction products were separated and determined by high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). As a result, SsGlc was found to hydrolyze the pentasaccharides, which possess three contiguous 1,4-β-glycosidic linkages (cellotetraose sequence) adjacent to 1,3-β-linkage, but none of the other oligosaccharides were hydrolyzed. To further analyze the specificity, kinetic measurements were performed using polymeric substrates and 4-methylumbelliferyl derivatives of laminaribiose and cellobiose (1,3-β-(Glc)2-MU and 1,4-β-(Glc)2-MU). The kcat/Km value obtained for barley β-glucan was considerably larger than that for lichenan, indicating that SsGlc prefers 1,3-1,4-β-glucan possessing a larger amount of cellotetraose sequence. This is consistent with the data obtained for 1,3-1,4-β-glucosyl oligosaccharides. However, the kcat/Km value obtained for 1,4-β-(Glc)2-MU was considerably lower than that for 1,3-β-(Glc)2-MU, suggesting inconsistency with the data obtained from the other natural substrates. It is likely that the kinetic data obtained from such chromophoric substrates do not always reflect the true enzymatic properties. 相似文献
26.
Noha M. Shafik Rasha A. Gaber Darin A. Mohamed Abla M. Ebeid 《Journal of biochemical and molecular toxicology》2019,33(6)
Ulcerative colitis (UC) is a chronic gastrointestinal disorder interfering with life quality. A total of 60 male Wistar rats were divided into four equal groups: Control (group I), hesperidin only (group II), UC untreated (group III), and UC treated with hesperidin (group IV). Hesperidin had modulatory effects on UC pathogenesis, which might be through alleviating colonic sphingosine phosphate phosphatase 2 messenger RNA expression and sphingosine kinase‐1 levels, thus suppressing the subsequent downstream inflammatory and apoptotic cascades represented by decreased macrophage inflammatory protein‐1α and enhancement of B‐cell lymphoma 2 immunohistochemistry expression. Also, it improved mitochondrial biogenesis by increasing the peroxisome proliferator‐activated receptor‐gamma‐coactivator 1‐α level. It successfully restored redox potential as evidenced by marked alleviations of the nitric oxide and peroxynitrite levels, increasing total antioxidant capacity, and activating the superoxide dismutase enzyme. Also, hesperidin alleviated the UC disease activity index and improved the histopathological picture. These findings may offer a new therapeutic strategy for UC treatment. 相似文献
27.
Susana Beatriz Etcheverry Evelina Gloria Ferrer Luciana Naso Josefina Rivadeneira Victoria Salinas Patricia Ana María Williams 《Journal of biological inorganic chemistry》2008,13(3):435-447
Vanadium compounds are known for a variety of pharmacological properties. Many of them display antitumoral and osteogenic
effects in several cell lines. Free radicals induce the development of tumoral processes. Natural polyphenols such as flavonoids
have antioxidant properties since they scavenge different free radicals. For these reasons it is interesting to investigate
the effects of a new complex generated between the vanadyl(IV) cation and the flavonoid hesperidin. The complex has been synthesized
and characterized by physicochemical methods. Spectroscopic analysis revealed a 1:1 stoichiometry of ligand:VO and coordination
by deprotonated cis-hydroxyl groups to the disaccharide moiety of the ligand. The complex improves the superoxide dismutase (SOD)-like activity
of the ligand, but the scavenging of other radicals tested does not change upon complexation. When tested on two tumoral cell
lines in culture (one of them derived from a rat osteosarcoma UMR106 and the other from human colon adenocarcinoma Caco-2),
the complex enhanced the antiproliferative effects of the free ligand, and this effect correlated with the morphological alterations
toward apoptosis. Also, on the osteoblastic cell line the complex stimulated cell proliferation and collagen type I production
at low concentrations. At higher doses the complex behaved as a cytotoxic compound for the osteoblasts. 相似文献
28.
Bernd Nidetzky Richard Griessler Alexandra Schwarz Barbara Splechtna 《Journal of Molecular Catalysis .B, Enzymatic》2004,29(1-6):241-248
We have cloned and sequenced the gene encoding cellobiose phosphorylase from Cellulomonas uda and report high yield production in Escherichia coli of a functional recombinant enzyme containing an N-terminal metal affinity fusion peptide. Use of heterologous gene expression increases the space-time yield of active phosphorylase by three orders of magnitude, compared to production of the enzyme with the natural organism. The full-length phosphorylase is a 91.3 kDa protein that consists of 821 amino acids and whose primary structure shares significant residue identity with different members of glycosyltransferase family 36. Purified enzyme was obtained in 39% overall yield by using copper-chelate and hydroxyapatite chromatographies. A comparative steady-state kinetic analysis for enzymatic reactions in the directions of phosphorolysis and synthesis of cellobiose at 30 °C and pH 6.6 demonstrates that the catalytic properties of the natural enzyme are retained completely in the recombinant cellobiose phosphorylase. The ability of the phosphorylase to utilize -
-glucose 1-fluoride (G1F) as alternate glucosyl donor in place of -
-glucose 1-phosphate (G1P) is exploited for the synthesis of β-1,4-glucosides under thermodynamic control in close to 100% yield. 相似文献
29.
30.
Yusuke Asano 《Bioscience, biotechnology, and biochemistry》2013,77(1):102-107
The stabilizing action of carboxymethyl cellulose (CMC-1 and CMC-2) on caseins was studied in the acidic pH region. CMC-1 stabilized 1% whole, α-, αS- and β-casein at pH 4.6 and 5.0, and at 5°C. But CMC-2 could not completely stabilize these caseins at pH 5.0. Interaction between κ-casein and CMC-1 commenced when pH was adjusted to 6.3, but CMC-2 interacted with κ-casein below pH 5.6. An αS- and κ-casein mixture (4 : 1) with CMC-2 was destabilized by the addition of 0.02 m NaCl or NaH2PO4 at pH 5.0. The αS/κ ratio of the precipitated casein was about 10. But the same system with CMC-1 was not destabilized by the salts. 相似文献