492-62-6Relevant articles and documents
Two new triterpenoid glycosides from Curculigo orchioides
Zuo, Ai-Xue,Shen, Yong,Jiang, Zhi-Yong,Zhang, Xue-Mei,Zhou, Jun,Lue, Jun,Chen, Ji-Jun
, p. 407 - 412 (2012)
Two new cycloartane triterpenoid glycosides, named curculigosaponin N and curculigosaponin O, were isolated from rhizomes of Curculigo orchioides Gaertn. Their structures were elucidated on the basis of comprehensive spectroscopic analysis including IR, M
Aryl sulfonic acid catalyzed hydrolysis of cellulose in water
Amarasekara, Ananda S.,Wiredu, Bernard
, p. 259 - 262 (2012)
Catalytic activities of eight alkyl/aryl sulfonic acids in water were compared with sulfuric acid of the same acid strength (0.0321 mol H+ ion/L) for hydrolysis of Sigmacell cellulose (DP ~ 450) in the 140-190 °C temperature range by measuring total reducing sugar (TRS), and glucose produced. Cellulose samples hydrolyzed at 160 °C for 3 h, in aqueous p-toluenesulfonic acid, 2-naphthalenesulfonic acid, and 4-biphenylsulfonic acid mediums produced TRS yields of 28.0, 25.4, and 30.3% respectively, when compared to 21.7% TRS produced in aqueous sulfuric acid medium. The first order rate constants at 160 °C in different acid mediums correlated with octanol/water distribution coefficient log D of these acids, except in the case of highly hydrophobic 4-dodceylbenzenesulfonic acid. In the series of sulfonic acids studied, 4-biphenylsulfonic acid appears to be the best cellulose hydrolysis catalyst.
Flavonoid glucuronides and a chromone from the aquatic macrophyte Stratiotes aloides
Conrad, Juergen,Foerster-Fromme, Bernhard,Constantin, Mihaela-Anca,Ondrus, Vladimir,Mika, Sabine,Mert-Balci, Fadime,Klaiber, Iris,Pfannstiel, Jens,Moeller, Wolfgang,Roesner, Harald,Foerster-Fromme, Karin,Beifuss, Uwe
, p. 835 - 840 (2009)
The first phytochemical analysis of the aquatic macrophyte Stratiotes aloides afforded two new flavonoid glucuronides, luteolin 7-O-β-D- glucopyranosiduronic acid-(12)-β-D-glucopyranoside (1) and chrysoeriol 7-O-β-D-glucopyranosiduronic acid-(12)-β-D- glu
Structural elements responsible for the glucosidic linkage-selectivity of a glycoside hydrolase family 13 exo-glucosidase
Saburi, Wataru,Rachi-Otsuka, Hiroaki,Hondoh, Hironori,Okuyama, Masayuki,Mori, Haruhide,Kimura, Atsuo
, p. 865 - 869 (2015)
Abstract Glycoside hydrolase family 13 contains exo-glucosidases specific for α-(1 → 4)- and α-(1 → 6)-linkages including α-glucosidase, oligo-1,6-glucosidase, and dextran glucosidase. The α-(1 → 6)-linkage selectivity of Streptococcus mutans dextran glucosidase was altered to α-(1 → 4)-linkage selectivity through site-directed mutations at Val195, Lys275, and Glu371. V195A showed 1300-fold higher kcat/Km for maltose than wild-type, but its kcat/Km for isomaltose remained 2-fold higher than for maltose. K275A and E371A combined with V195A mutation only decreased isomaltase activity. V195A/K275A, V195A/E371A, and V195A/K275A/E371A showed 27-, 26-, and 73-fold higher kcat/Km for maltose than for isomaltose, respectively. Consequently, the three residues are structural elements for recognition of the α-(1 → 6)-glucosidic linkage.
Acremonoside, a phenolic glucoside from the sea fan-derived fungus Acremonium polychromum PSU-F125
Khamthong, Nanthaphong,Rukachaisirikul, Vatcharin,Pakawatchai, Chaveng,Saithong, Saowanit,Phongpaichit, Souwalak,Preedanon, Sita,Sakayaroj, Jariya
, p. 50 - 54 (2014)
A new phenolic glucoside, acremonoside (1), along with two known compounds, F-11334 A2and 2,2-dimethyl-2H-chromen-6-ol, were isolated from the sea fan-derived fungus Acremonium polychromum PSU-F125. The structure of 1 was elucidated by spectroscopic techniques, acid hydrolysis and X-ray crystallographic analysis. The isolated compounds were tested for antibacterial, antimalarial, antimycobacterial and cytotoxic activities.
Two new secondary metabolites from xylaria sp. cfcc 87468
Wang, Fuqian,Han, Shishi,Hu, Song,Xue, Yongbo,Wang, Jianping,Xu, Hongfeng,Chen, Lu,Zhang, Geng,Zhang, Yonghui
, p. 1250 - 1257 (2014)
A new isocoumarin glycoside, 3R-(+)-5-O-[6'-O-Acetyl]-A-D-glucopyranosyl-5- hydroxymellein (1), and a new phenylethanol glycoside, (-)-phenylethyl-8-O-A-L- rhamnopyranoside (2), were isolated from the ethyl acetate extract of the fungus Xylaria sp. cfcc 87468, together with five known steroids, ss-sitosterol (3), stigmast-4-en-3- one (4), ergosterol (5), (22E)-cholesta-4,6,8(14),22- tetraen-3-one (6), and 4a-methylergosta- 8(14),24(28)-dien-3ss-ol (7). The structures of compounds 1 and 2 were elucidated by MS, extensive 1D and 2D NMR spectroscopy, and the circular dichroism (CD) spectroscopy.
Aglycon specificity profiling of α-glucosidases using synthetic probes
Hakamata, Wataru,Muroi, Makoto,Kadokura, Kazunari,Nishio, Toshiyuki,Oku, Tadatake,Kimura, Atsuo,Chiba, Seiya,Takatsuki, Akira
, p. 1489 - 1492 (2005)
We designed and synthesized hydrogen bond based probes 1-8 with the exception of known glycosidase inhibition mechanisms, and aglycon specificity of 11 different sources of α-glucosidases were investigated using their probes. Probe 4 (2,6-anhydro-1-deoxy-1-[(1-oxopentyl-5-hydroxy)amino]-d-glycero- d-ido-heptitol) showed a potent inhibition of S. cerevisiae α-glucosidase among all α-glucosidases. Probe 4 was found to be a competitive inhibitor for S. cerevisiae α-glucosidase with Ki 0.13 mM.
Antibacterial activity of glucomoringin bioactivated with myrosinase against two important pathogens affecting the health of long-term patients in hospitals
Galuppo, Maria,De Nicola, Gina Rosalinda,Iori, Renato,Dell'Utri, Pia,Bramanti, Placido,Mazzon, Emanuela
, p. 14340 - 14348 (2013)
Glucosinolates (GLs) are natural compounds present in species of the order Brassicales and precursors of bioactive isothiocyanates (ITCs). In the recent years, they have been studied mainly for their chemopreventive as well as novel chemotherapeutics properties. Among them 4-(α-L-rhamnosyloxy)benzyl glucosinolate (glucomoringin; GMG), purified from seeds of Moringa oleifera Lam., a plant belonging to the Moringaceae family, represents an uncommon member of the GL family with peculiar characteristics. This short communication reports new evidences about the properties of GMG and presents a new innovative utilization of the molecule. The bioactivation of GMG by myrosinase enzyme just before treatment, permits to maximize the power of the final product of the reaction, which is the 4-(α-L-rhamnosyloxy)benzyl isothiocyanate (GMG-ITC). We tested the antibiotic activity of this latter compound on two strains of pathogens affecting the health of patients in hospital, namely Staphylococcus aureus and Enterococcus casseliflavus, and on the yeast Candida albicans. Results show that the sensibility of S. aureus BAA-977 strain and E. casseliflavus to GMG-ITC treatment reveals an important possible application of this molecule in the clinical care of patients, more and more often resistant to traditional therapies.
Purification, antioxidant activity and antiglycation of polysaccharides from Polygonum multiflorum Thunb
Lv, Lishuang,Cheng, Yunhui,Zheng, Tiesong,Li, Xiaoming,Zhai, Rong
, p. 765 - 773 (2014)
Polysaccharides, one of the most important constituents in Polygonum multiflorum Thunb, a famous Chinese medicinal herb, were isolated by DEAE-52, Sepharose 4B and Sephacryl S-300 column chromatography. Two polysaccharides (PMP-1 and PMP-2) were identified as homogeneous in molecular weight with HPLC. The molecular weights were 4.8 × 102 and 6.1 × 10 2 kDa, respectively. Antioxidant activity tests were performed with two polysaccharides at concentrations of 0.1-1.5 mg/mL. The results indicated that the inhibitory activity on oxidation and glycation exhibited a dose-dependent response. PMP-2 exhibited a much stronger antioxidant capacity against free radical, lipid oxidation and protein glycation. The IC50 values of PMP-2 were 0.47, 0.6 and 0.93 mg/mL for superoxide anion scavenging, hydroxyl radical scavenging, and hydroxyl peroxide scavenging, respectively. The inhibitory ability of PMP-2 on lipid oxidation was most markedly in rat liver, followed by heart and kidney. Meanwhile, PMP-2 also showed satisfactory suppression of AGEs formation. This suggested that the polysaccharides present in PM can contribute to the biological effects.
Asplenetin, a flavone and its glycoside from Launaea asplenifolia
Gupta,Ahmed, Bahar
, p. 873 - 875 (1985)
A new flavone, asplenetin, has been isolated from Launea asplenifolia and characterized as 5,7,3′,4′,5′-pentahydroxy-3-(3-methylbutyl)flavone. Its glycoside, asplenetin 5-O-neohesperidoside, is also reported.
Sonochemical synthesis of HSiW/graphene catalysts for enhanced biomass hydrolysis
Klein, Miri,Varvak, Alexander,Segal, Elad,Markovsky, Boris,Pulidindi, Indra Neel,Perkas, Nina,Gedanken, Aharon
, p. 2418 - 2425 (2015)
Hydrolysis of biomass for the production of glucose was studied. Silicotungstic acid (HSiW) was deposited on graphene by an ultrasound-assisted procedure. The catalyst (HSiW/G) was characterized using a variety of physico-chemical methods. Homogeneous distribution of HSiW on the surface of graphene was demonstrated. The hydrolysis of glycogen was performed with a HSiW/G catalyst by hydrothermal treatment. The yield of glucose (66 wt%) obtained was about 8 times higher than that obtained with the same amount of bare HSiW. Stability of the HSiW/graphene even after 3 repeated uses was confirmed. The mechanism of the enhancement of catalytic activity was discussed in terms of a special interaction between the graphene support and HSiW and also the appearance of hydrophobic cavities on the surface of graphene. The formation of these cavities facilitates the anchoring of glycogen to the catalyst surface and promotes the attack of protons that leads to selective, rapid, and efficient hydrolysis.
Exopolysaccharide Produced by Probiotic Bacillus albus DM-15 Isolated From Ayurvedic Fermented Dasamoolarishta: Characterization, Antioxidant, and Anticancer Activities
Kalimuthu, Palanisamy,Ma, Yongkun,Mathivanan, Krishnamurthy,Rai, Amit Kumar,Saravanan, Kandasamy,Sathiyanarayanan, Ganesan,Sekar, Soundarapandian,Sudharsan, Kumaresan,Vinothkanna, Annadurai
, (2022/03/31)
An exopolysaccharide (EPS) was purified from the probiotic bacterium Bacillus albus DM-15, isolated from the Indian Ayurvedic traditional medicine Dasamoolarishta. Gas chromatography-mass spectrophotometry and nuclear magnetic resonance (NMR) analyses revealed the heteropolymeric nature of the purified EPS with monosaccharide units of glucose, galactose, xylose, and rhamnose. Size-exclusion chromatography had shown the molecular weight of the purified EPS as around 240 kDa. X-ray powder diffraction analysis confirmed the non-crystalline amorphous nature of the EPS. Furthermore, the purified EPS showed the maximum flocculation activity (72.80%) with kaolin clay and emulsification activity (67.04%) with xylene. In addition, the EPS exhibits significant antioxidant activities on DPPH (58.17 ± 0.054%), ABTS (70.47 ± 0.854%) and nitric oxide (58.92 ± 0.744%) radicals in a concentration-dependent way. Moreover, the EPS showed promising cytotoxic activity (20 ± 0.97 μg mL–1) against the lung carcinoma cells (A549), and subsequent cellular staining revealed apoptotic necrotic characters in damaged A549 cells. The EPS purified from the probiotic strain B. albus DM-15 can be further studied and exploited as a potential carbohydrate polymer in food, cosmetic, pharmaceutical, and biomedical applications.
Enzyme aggregation and fragmentation induced by catalysis relevant species
Adair, James,Bhide, Ashlesha,Gentile, Kayla,Ghosh, Subhadip,Kauffman, Joshua,Lee, Tae-Hee,Maiti, Subhabrata,Sen, Ayusman
, p. 20709 - 20717 (2021/10/02)
It is usually assumed that enzymes retain their native structure during catalysis. However, the aggregation and fragmentation of proteins can be difficult to detect and sometimes conclusions are drawn based on the assumption that the protein is in its native form. We have examined three model enzymes, alkaline phosphatase (AkP), hexokinase (HK) and glucose oxidase (GOx). We find that these enzymes aggregate or fragment after addition of chemical species directly related to their catalysis. We used several independent techniques to study this behavior. Specifically, we found that glucose oxidase and hexokinase fragment in the presence ofd-glucose but notl-glucose, while hexokinase aggregates in the presence of Mg2+ion and either ATP or ADP at low pH. Alkaline phosphatase aggregates in the presence of Zn2+ion and inorganic phosphate. The aggregation of hexokinase and alkaline phosphatase does not appear to attenuate their catalytic activity. Our study indicates that specific multimeric structures of native enzymes may not be retained during catalysis and suggests pathways for different enzymes to associate or separate over the course of substrate turnover.