58-86-6Relevant articles and documents
Aqueous ionic liquids and deep eutectic solvents for cellulosic biomass pretreatment and saccharification
Xia, Shuqian,Baker, Gary A.,Li, Hao,Ravula, Sudhir,Zhao, Hua
, p. 10586 - 10596 (2014)
Ionic liquids (ILs) have proven effective solvents for pretreating lignocellulose, leading to the fast saccharification of cellulose and hemicellulose. However, the high cost of most ILs remains a major barrier to commercializing this recent approach at a practical scale. As a strategic detour, aqueous solutions of ILs are also being explored as less costly alternatives to neat ILs for cellulose pretreatment. However, limited studies on a few select IL systems are known and there remains no systematic survey of various ILs, eluding an in-depth understanding of pretreatment mechanisms afforded by aqueous IL systems. As a step toward filling this gap, this study presents results for Avicel cellulose pretreatment by neat and aqueous solutions (1.0 and 2.0 M) of 20 different ILs and three deep eutectic solvents, correlating enzymatic hydrolysis rates of pretreated cellulose with various IL properties such as hydrogen-bond basicity, polarity, Hofmeister ranking, and hydrophobicity. The pretreatment efficiencies of neat ILs may be loosely correlated to the hydrogen-bond basicity of the constituent anion and IL polarity; however, the pretreatment efficacies for aqueous ILs are more complicated and cannot be simply related to any single IL property. Several aqueous IL systems have been identified as effective alternatives to neat ILs in lignocellulose pretreatment. In particular, this study reveals that aqueous solutions of 1-butyl-3-methylimidazolium methanesulfonate ([BMIM][MeSO 3]) are effective for pretreating switchgrass (Panicum virgatum), resulting in fast saccharification of both cellulose and hemicellulose. An integrated analysis afforded by X-ray diffraction, scanning electron microscopy, thermogravimetric analysis and cellulase adsorption isotherm of lignocellulose samples is further used to deliver a more complete view of the structural changes attending aqueous IL pretreatment.
Enzymatic Hydrolysis of Black Liquor Xylan by a Novel Xylose-Tolerant, Thermostable β-Xylosidase from a Tropical Strain of Aureobasidium pullulans CBS 135684
Bankeeree, Wichanee,Akada, Rinji,Lotrakul, Pongtharin,Punnapayak, Hunsa,Prasongsuk, Sehanat
, p. 919 - 934 (2018)
From three cell-associated β-xylosidases produced by Aureobasidium pullulans CBS 135684, the principal enzyme was enriched to apparent homogeneity and found to be active at high temperatures (60–70?°C) over a pH range of 5–9 with a specific activity of 163.3?units (U) mg?1. The enzyme was thermostable, retaining over 80% of its initial activity after a 12-h incubation at 60?°C, with half-lives of 38, 22, and 10?h at 60, 65, and 70?°C, respectively. Moreover, it was tolerant to xylose inhibition with a Ki value of 18?mM. The Km and Vmax values against p-nitrophenyl-β-d-xylopyranoside were 5.57?±?0.27?mM and 137.0?±?4.8?μmol?min?1?mg?1 protein, respectively. When combining this β-xylosidase with xylanase from the same A. pullulans strain, the rate of black liquor xylan hydrolysis was significantly improved by up to 1.6-fold. The maximum xylose yield (0.812?±?0.015?g?g?1 dry weight) was obtained from a reaction mixture containing 10% (w/v) black liquor xylan, 6?U?g?1 β-xylosidase and 16?U?g?1 xylanase after incubation for 4?h at 70?°C and pH 6.0.
A new cycloartane triterpene glycoside from Souliea vaginata
Wu, Hai-Feng,Zhang, Gang,Wu, Mei-Chun,Yang, Wen-Ting,Ma, Guo-Xu,Chen, Di-Zhao,Xu, Xu-Dong,Zou, Qiong-Yu,Hu, Wei-Cheng
, p. 2316 - 2322 (2016)
A new cycloartane-type triterpene glycoside, namely soulieoside M (1), and one known compound, beesioside I (2), were isolated from the ethanolic extract of the rhizomes of Souliea vaginata. Their structures were determined spectroscopically and compared with previously reported spectral data. Compounds 1 and 2 were evaluated for their cytotoxic activities against three human cancer cell lines.
Three new cycloart-7-ene triterpenoid glycosides from Cimicifuga dahurica and their anti-inflammatory effects
Pang, Qian-Qian,Mei, Yu-Dan,Zhang, Yuan-Chu,Liu, Ling-Xian,Shi, Dan-Feng,Pan, Da-Bo,Yao, Xin-Sheng,Li, Hai-Bo,Yu, Yang
, p. 3634 - 3643 (2021)
Ten cycloart-7-ene triterpenoid glycosides, including three new compounds (1–3), were isolated from the roots of Cimicifuga dahurica. Their structures were elucidated on the basis of extensive spectroscopic analyses, chemical methods and comparison with literatures. In addition, the isolates were evaluated for their inhibitory effects on the production of NO, as well as the expressions of iNOS and COX-2 in LPS-stimulated RAW 264.7 macrophages. The results showed that compounds 3, 5, 6, 7 and 8 can reduce the release of NO in a dose-dependent manner. Mechanistically, Western blot analysis indicated that the NO inhibitory effects relied on down-regulating the expression of iNOS, and partially associated with lowering the expression of COX-2.
One new and seven known triterpene glycosides from the aerial parts of Cimicifuga dahurica
Hao, Yi-Meng,Luo, Wen,Jiang, Guan-Ze,Lv, Chong-Ning,Lu, Jin-Cai
, p. 788 - 793 (2020)
One new triterpene glycoside, asiaticoside I (1), along with seven known ones (2–8), were isolated from the aerial parts of Cimicifuga dahurica (Turcz.) Maxim. The structure of 1 was elucidated on the basis of extensive spectroscopic methods including 1D-NMR, 2D-NMR and MS data. The structures of known compounds were determined by comparison with the literature data. Compound 1 exhibited moderate cell growth inhibitory activities in vitro against HELF, non-small cell lung cancer A549, and pancreatic cancer PANC-1 cell lines, with IC50 values of 62.97, 43.19, and 60.40 μM, respectively.
Hydrothermal production of furfural from xylose and xylan as model compounds for hemicelluloses
Moeller, Maria,Schroeder, Uwe
, p. 22253 - 22260 (2013)
The uncatalyzed microwave-assisted hydrothermal conversion of xylose and xylan as hemicellulose model compounds to furfural at temperatures of 160-240 °C and reaction times of 5-240 min is investigated. With acceptable reaction rates at 200 °C the conversion of xylose provides furfural with a maximum yield of 49%. The conversion of xylan, however, requires lower temperatures (160-180 °C) in order to promote the hydrolysis of the polymer, yielding xylose as a furfural precursor. The Royal Society of Chemistry 2013.
Evasteriosides A and B and other sulfated steroids from the Pacific starfish Evasterias retifera
Levina,Kalinovskii,Andriyashchenko,Dmitrenok
, p. 2431 - 2436 (2008)
Two new polar steroidal glycosides identified as sodium (20R,22E,24R,25S)-3-O-(β-d-xylopyranosyl)-24-methyl-5α-cholest-22- ene-3β,6β,8,15α,26-pentol 26-sulfate (evasterioside A) and sodium (20R,22E)-24-O-(β-d-xylopyranosyl)-5α-cholest-22-ene-3β, 6β,8,15α,24-pentol 3-sulfate (evasterioside B) were isolated from the Pacific starfish Evasterias retifera collected in the Sea of Japan. Five known compounds, viz., coscinasterioside B, aphelasterioside A, marthasterone 3-sulfate and (20R)-cholest-7-en-3β-ol and cholesterol sulfates, were identified. The structures of the new natural compounds were established using their 2D NMR and mass spectra and some chemical transformations.
Soulieoside O, a new cyclolanostane triterpenoid glycoside from Souliea vaginata
Wu, Hai-Feng,Li, Peng-Fei,Zhu, Yin-Di,Zhang, Xiao-Po,Ma, Guo-Xu,Xu, Xu-Dong,Liu, Yi-Lin,Luo, Zheng-Hong,Chen, Di-Zhao,Zou, Qiong-Yu,Zhao, Zi-Jian
, p. 1177 - 1182 (2017)
A new cyclolanostane triterpenoid glycoside, soulieoside O (1), together with 25-O-acetylcimigenol-3-O-β-d-xylopyranoside (2) and cimigenol-3-O-β-d-xylopyranoside (3), was isolated from the rhizomes of Souliea vaginata. Their structures were characterized by spectroscopic analysis and chemical methods. The new compound showed moderate inhibitory activity against three human cancer cell lines with IC50 values of 9.3–22.5?μM.
Triterpenoids and Flavonoids from the Leaves of Astragalus membranaceus and Their Inhibitory Effects on Nitric Oxide Production
Wang, Zhi-Bin,Zhai, Ya-Dong,Ma, Zhen-Ping,Yang, Chun-Juan,Pan, Rong,Yu, Jia-Li,Wang, Qiu-Hong,Yang, Bing-You,Kuang, Hai-Xue
, p. 1575 - 1584 (2015)
Four new cycloartane triterpenes, named huangqiyegenins V and VI and huangqiyenins K and L (1-4, resp.), together with nine known triterpenoids, 5-13, and eight flavonoids, 14-21, were isolated from a 70%-EtOH extract of Astragalus membranaceus leaves. The structures of the new compounds were elucidated by detailed spectroscopic analyses, and the compounds were identified as (9β,11α,16β,20R,24S)-11,16,25-trihydroxy-20,24-epoxy-9,19-cyclolanostane-3,6-dione (1), (9β,16β,24S)-16,24,25-trihydroxy-9,19-cyclolanostane-3,6-dione (2), (3β,6α,9β,16β,20R,24R)-16,25-dihydroxy-3-(β-D-xylopyranosyloxy)-20,24-epoxy-9,19-cyclolanostan-6-yl acetate (3), and (3β,6α,9β,16β,24E)-26-(β-D-glucopyranosyloxy)-16-hydroxy-3-(β-D-xylopyranosyloxy)-9,19-cyclolanost-24-en-6-yl acetate (4). All isolated compounds were evaluated for their inhibitory activities against LPS-induced NO production in RAW264.7 macrophage cells. Compounds 1-3, 14, 15, and 18 exhibited strong inhibition on LPS-induced NO release by macrophages with IC50 values of 14.4-27.1μM.
A new triterpene and phenolic compounds from the roots of Pteroxygonum giraldii
Chai, Xin,Su, Yan-Fang,Zhang, Jun,Yan, Shi-Lun,Gao, Yan-Hong,Gao, Xiu-Mei
, p. 127 - 133 (2012)
A chemical investigation of the roots of Pteroxygonum giraldii led to the isolation of a new arborane-type triterpene, pteroxygonumnol A (1), a new myricetin glycoside, myricetin 3-O-β-D-galactopyranoside 3′-O-β-D-xylopyranoside (2), and a group of phenolic lipids, 3-6, along with four known phenolic compounds, (-)-epigallocatechin, (-)-epigallocatechin gallate, gallic acid, and 2-(4-hydroxyphenyl)acetic acid. Their structures were elucidated on the basis of extensive spectroscopic analyses. Copyright
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Sieber
, p. 1433,1436 (1972)
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Hudson,Harding
, p. 1038 (1917)
A New Diarylheptanoid from the Twigs of Quercus Acutissima and their Neuroprotective Activity
Cha, Joon Min,Subedi, Lalita,Khan, Zahra,Kim, Sun Yeou,Lee, Kang Ro
, p. 213 - 216 (2020)
A new diarylheptanoid glycoside, acutissioside A (4), along with five known diarylheptanoids (1–3, 5, 6) was isolated from the twigs of Quercus acutissima Carruth. The structure of the new compound was determined via spectral analysis, including NMR spectra (1H and 13C NMR, 1H–1H COSY, HSQC, HMBC) and HR-ESI-MS, acid hydrolysis, and specific optical rotation data. The neuroprotective effect of all the diarylheptanoid compounds (1–6) was evaluated. Compound 1 exhibited NGF secretion to 154.60 ± 2.87%, which was stronger than that of the positive control 6-shogaol (140.45 ± 2.18%).
Lignan glucosides from sinomenium acutum rhizomes
Kim, Ki Hyun,Moon, Sae Rom,Kim, Chung Sub,Woo, Kyeong Wan,Choi, Sang Un,Lee, Kang Ro
, p. 2144 - 2147 (2013)
The new lignan glucoside, acutumoside (1), was isolated from Sinomenium acutum rhizomes together with nine known compounds (2-10). The structure of 1 was elucidated on the basis of extensive spectroscopic analyses, including two-dimensional nuclear magnet
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Isbell,Frush
, p. 1309,1315 (1958)
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Comparative study on the structural characterization and α-glucosidase inhibitory activity of polysaccharide fractions extracted from Sargassum fusiforme at different pH conditions
Jia, Rui-Bo,Li, Zhao-Rong,Lin, Lianzhu,Luo, Donghui,Ou, Zhi-Rong,Zhao, Mouming,Zheng, Qianwen
, p. 602 - 610 (2021/11/30)
Sargassum fusiforme polysaccharides (SFPs), including SFP-3-40, SFP-3-60, SFP-3-80, SFP-7-40, SFP-7-60, SFP-7-80, SFP-10-40, SFP-10-60, and SFP-10-80, were extracted at different pH (3, 7, and 10), and then precipitated with graded precipitation of 40%, 60% and 80% (v/v) ethanol solution, respectively. Their physicochemical properties and α-glucosidase inhibitory activity were determined. Results showed that SFPs significantly differed in the contents of total sugar, protein, uronic acid, sulfate, the zeta potential, and molecular weight distribution. SFPs, including SFP-10-40, SFP-10-60, and SFP-10-80, had bigger absolute zeta potential value and higher respective average molecular weight in the same ethanol concentration precipitate. All samples were mainly composed of fucose, glucuronic acid, and mannose with different molar ratios. The extraction pH and precipitation ethanol solution concentration caused little changes in functional groups, but significantly altered surface morphology of SFPs. Congo red test revealed that all polysaccharides were not helical polysaccharides. Rheological measurements indicated that SFPs were pseudoplastic fluids and showed elastic behavior of the gel. Except SFP-3-40 and SFP-3-60, all other samples had a stronger α-glucosidase inhibitory activity than that of acarbose. The inhibition type of SFPs against α-glucosidase varied owing to different extraction pH and precipitation ethyl concentration. This study shows that extraction pH can significantly affect the structure and hypoglycemic activity of SFPs and provide a data support for the scientific use of Sargassum fusiforme in industrial production.
A new isoflavone glycoside from flowers of Pueraria Montana var. lobata (Willd.) Sanjappa & Pradeep
Ma, Yilong,Shang, Yafang,Zhong, Zhifeng,Zhang, Yingshuo,Yang, Yang,Feng, Jun,Wei, Zhaojun
, p. 1459 - 1464 (2019/08/26)
A new isoflavone glycoside, named 3’-hydroxytectorigenin-7-O-β-D-xylosyl-(1→6)-β-D-glucopyranoside (1) was isolated from the flowers of Pueraria montana var. lobata (Willd.) Sanjappa & Pradeep. The structure of compound 1 was characterised by HR-ESI-MS and NMR spectroscopic methods. In radical scavenging activity test using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), compound 1 showed moderate activity with IC50 value of 42 ± 4.2 μg/mL.