CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Jiaojiao Lu,Hai Yang,Jie Hao,Chengling Wu,Li Liu,Naiyu Xu,Robert J. Linhardt,Zhenqing Zhang
Alginate is a linear and acidic polysaccharide , composed of (1 → 4) linked β- d -mannuronic acid (ManA) and α- l -guluronic acid (GulA). The ratio of ManA to GulA ( M / G ) is one of the most important factors for the application of alginate and its derivatives in various areas. In this work, a robust and accurate method was developed to analyze M / G using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The impact of hydrolysis conditions on the release patterns of ManA and GulA from alginate and its derivatives was investigated. The release patterns of ManA and GulA need to be considered separately to obtain an accurate M / G . Several hydrolysis conditions were established that released ManA and GulA completely and maintained these saccharide residues intact. The proper M / G of alginates from different sources and its derivatives could then be calculated by integration of the corresponding ManA and GulA peaks.
研究领域:
生物化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2021
·
IF 6.953
Dan Liu,Wei Tang,Yue Xin,Ze-Xia Wang,Xiao-Jun Huang,Jie-Lun Hu,Jun-Yi Yin,Shao-Ping Nie,Ming-Yong Xie
Polysaccharides were extracted by hot water and alkali in sequence from Dolichos lablab L. hull, and further purified by ion-exchange and gel columns. Hot water extracted D. lablab hull polysaccharide (DLHP) was rich in glucuronoxylan and pectin, and alkali extracted polysaccharide (DLHAP) mostly embraced glucuronoxylan. The structures of purified glucuronoxylans from DLHP and DLHAP were mainly analyzed by HPAEC-PAD, methylation combined with GC–MS, NMR and SEC-MALLS. DLHP-1 was identified as acetylated glucuronoxylan containing →4)-β-Xyl p- (1→ backbone with substitution at O -2 site by α-Glc p A/4- O -methyl-α-Glc p A. The molar ratio of β-Xyl p to α-Glc p A was 6.9:1, and acetylation was mainly at O -3 site of β-Xyl p with acetylation degree of 21.5%. DLHP-1 and DLHP-2 had similar physicochemical properties, except for molecular weight ( M w ). DLHAP-1 was the non-methylated glucuronoxylan almost without acetylation, and it had the molar ratio of β-Xyl p to α-Glc p A of 5.6:1. Besides, DLHP-1 ( M w of 20.0 × 10 3 g mol −1 ) adopted semi-flexible chain, while DLHAP-1 ( M w of 15.4 × 10 3 g mol −1 ) showed flexible chain. These results provided a structural basis for study on polysaccharides from D. lablab hull, which was benefit for understanding biological activities and developing functional food or pharmaceuticals of D. lablab .
研究领域:
植物化学
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食品科学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE RESEARCH
·
2022
·
IF 2.975
Fangxia Wu,Na Yan,Yan Guo,Xiaoxiao Yu,Lin Yi,Yilan Ouyang,Xin Wang,Zhenqing Zhang
The TEMPO/NaBr/NaClO system was used to modify konjac glucomannan and prepare β-1,4-linked D-mannuronic/glucuronic acid oligosaccharides . The impact of oxidant amount on the degree of oxidation , molecular weight , terminal structure and the ratio of sugar units were systematically investigated. Mannoses were transformed to mannuronic acids quantitatively, while some glucose were transformed to glucuronic acids, some degraded. The unspecific oxidation causes strong degradation of konjac glucomannan sugar chains. Multiple terminal structures were observed in the oxidized KGM products. According to those observations, the oxidation pattern of konjac glucomannan with the TEMPO/NaBr/NaClO system was speculated. It is suggested that the axial hydroxyl group at position 2 in mannose might form a hydrogen bond with the oxygen on the sugar ring. It would against the unspecific oxidation. While, both specific and unspecific oxidations were observed at glucose units with an equatorial hydroxyl group at position 2, and the degradation occurs mostly on glucose during the oxidation.
研究领域:
生物化学
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食品科学
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产品关联
DOI
PubMed
高影响因子
PeerJ
·
2025
·
IF 2.4
Shu-Dong Zhang,Ling-Ling Chen,Chao-Yue Li,Xiao-Qing Long,Xue Yang,Xiao-Duo He,Li-Wen Du,Heng-Feng Yang,Li-Zhen Ling
Diaporthe Z1-1N, the primary causal agent of soft rot disease in kiwifruit, exhibited higher pectinase activity compared to cellulase activity in both in vitro and in vivo incubation models. To gain deeper insights into the role of pectinases in the pathogenicity of this fungus, we evaluated the effects of incubation temperature (ranging from 18 to 38 °C), duration (1 to 7 days), and medium pH (4.0 to 9.0) on the activities of two crucial pectinases: polygalacturonase (PG) and polymethylgalacturonase (PMG). Our single-factor experiments revealed that the optimal conditions for maximizing PMG yield were a pH of 7.5 and a temperature of 28 °C, with peak activity occurring after three days of incubation. Notably, PG activity peaked on the fourth day under the same pH and temperature conditions. Under the optimal conditions identified through an orthogonal experimental design, PMG exhibited higher activity than PG. Further analysis showed that temperature was the most influential factor on PMG activity, followed by incubation duration and pH. The lesion size caused by the purified pectinase extracts was 50% the lesion size that caused by the fungal mycelium of Diaporthe Z1-1N. These findings underscore the significance of PG and PMG as key virulence factors in the pathogenicity of Diaporthe Z1-1N, providing a solid scientific basis for future research into the functions of these enzymes.
研究领域:
植物病理学
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酶学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2021
·
IF 6.025
Hui Lv,Juanjuan Wang,Mingying Wang,Li Shen,Ling Xiao,Taijie Chen,Tingzhe Sun,Wenjuan Li,Liangliang Zhu,Xiaoke Zhang
Organotin compounds (OTs) act as potent endocrine disruptors that are often found in polluted food and water. UDP-glucuronosyltransferases (UGTs) are responsible for termination of multiple endogenous hormones. This study was conducted to investigate the inhibitory effects of two tri-submitted OTs tributyltin (TBT) and triphenyltin (TPT), against activities of UGTs. It is revealed that TBT and TPT act as two potent inhibitors for multiple UGTs. UGT1A8 and -2B15 were coinhibited by the two OTs. UGT1A1 and -1A10 were inhibited by TPT, whereas UGT 2B4 and -2B7 were inhibited by TBT. Kinetic analyses further indicated that TBT and TPT are two competitive nanomolar inhibitors of UGT2B15, with K i values of 0.45 and 0.46 μM, respectively. K i values for the other UGTs are determined to be a few micromolars. In addition, the two OTs displayed effective inhibition against UGT2B15 in catalyzing dihydrotestosterone glucuronidation, with IC50 values both in nano-molar range. TPT can additionally inhibit activities of UGT1A1 and -1A10 in estradiol-3-O-glucuronidation, with IC50 values of a few micro-molars. These results indicated that the two OTs can extensively interfere with glucuronidation of endogenous hormones, which may act as a new potential mechanism resulting in endocrine disrupting actions.
研究领域:
毒理学
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环境科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD BIOCHEMISTRY
·
2020
·Vol. 44
·期 3
·e13133
·
IF 1.662
Haidong Tan,Guojun Yang,Wei Chen,Qishun Liu,Kuikui Li,Heng Yin
Endo-polygalacturonase II B (PgaB) from Aspergillus luchuensis was orthologous to endo-polygalacturonase from Aspergillus niger with mutant sites Thr42Ser and Glu52Ala. Mature pga B gene was cloned from the genomic DNA of A. luchuensis and secreted expressed with over 90% purity in Pichia Pastoris and reached 1.0 g/L after 144 hr culture. The recombinant PgaB was further purified by Ni-NTA chromatography. Using polygalacturonic acid (PGA) as substrate, the optimal condition for PgaB activity was 40°C and pH 4.5, respectively. Km and Vmax of PgaB were 0.19 mmol/l and 103.58 μmol min −1 mg −1 , respectively. The relative activity of PgaB remained more than 60% and 40% of maximum activity at 50 and 60°C for 7 hr. PgaB increased the light transmittance by 85% and showed high efficiency in juice clarification. The main product was galacturonic acid oligosaccharides with degrees of polymers (DP) 1–3. The PgaB is a potential pectinolytic enzyme in food industries. Practical applications Endo-polygalacturonase II B (PgaB) was identified from Aspergillus luchuensis , a filamentous fungus widely used in food and beverage fermentation in East Asia. PgaB still kept its most activity at 60°C for 7 hr. Polygalacturonic acid (PGA) can be digested effectively by the PgaB and the main products are galacturonic acid oligosaccharides with degrees of polymers (DP) 1–3. PgaB shows high efficiency in juice clarification. The PgaB is a potential pectinolytic enzyme for the applications in food industries.
研究领域:
酶学
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食品科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Pharmacology
·
2022
·
IF 5.988
Zeng Wanying,Liu Xiaojing,Wu Yangyang,Cai Yuting,Li Zhennan,Ye Fei,Sun Yuanhong,Li Feng,Xing Huijie,Wang Shuai
Glucuronidation catalyzed by UDP-glucuronosyltransferases (UGTs) is one of the most important phase II mechanisms, facilitating drug clearance via conjugation of glucuronic acid with polar groups of xenobiotics. Accumulating evidence suggests that IBDs impact drug disposition, but whether and how IBDs regulate UGTs and drug glucuronidation remains undefined. In this study, we aim to investigate the expression of UGTs and drug glucuronidation in experimental colitis. Given that glucuronidation occurs primarily in the liver, we analyzed the mRNA changes in hepatic UGTs with a DSS-induced mouse colitis model. Twelve UGTs were downregulated in the liver of colitis mice including UGT1A1 and UGT1A9 (two representative UGTs). Colitis in mice downregulated UGT1A1 and UGT1A9 in the liver but not in small intestine, colon, and kidney. We also established that the downregulation of UGTs was attributed to the disease itself rather than the DSS compound. Moreover, colitis-reduced UGT1A1 and UGT1A9 lead to dampened baicalein and puerarin glucuronidation. PXR was the only UGT regulator significantly downregulated in colitis mice, suggesting dysregulation of PXR is associated with the downregulation of UGT1A1 and UGT1A9, thereby potentially resulting in dysfunction of baicalein and puerarin glucuronidation. Collectively, we establish that UGTs and glucuronidation are dysregulated in colitis, and this effect may cause variation in drug responsiveness in IBDs.
研究领域:
药理学
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胃肠病学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Frontiers in Pharmacology
·
2021
·
IF 5.811
Liu Shuaibing,Hou Lei,Li Cai,Zhao Yibo,Yao Xia,Zhang Xiaojian,Tian Xin
Ticagrelor is the first reversibly binding, direct-acting, oral P2Y12 receptor inhibitor. The contribution of UDP-glucuronosyltransferases (UGTs) enzymes to the metabolism of ticagrelor to its glucuronide conjugation, ticagrelor-O-glucuronide, in human liver microsomes (HLM) and human intestinal microsomes (HIM), was well characterized in the current study. The inhibition potential of human major UGTs by ticagrelor and ticagrelor-O-glucuronide was explored. The inhibitory effects of ticagrelor-O-glucuronide on cytochrome P450s (CYPs) enzymes were investigated as well. Ticagrelor glucuronidation exhibits substrate inhibition kinetics in both HLM and HIM with apparent Km values of 5.65 and 2.52 μM, Vmax values of 8.03 and 0.90 pmol min−1·mg protein−1, Ksi values of 1,343.0 and 292.9 respectively. The in vitro intrinsic clearances (Vmax/Km) for ticagrelor glucuronidation by HLM and HIM were 1.42 and 0.36 μl min−1·mg protein−1, respectively. Study with recombinant human UGTs suggested that multiple UGT isoforms including UGT1A9, UGT1A7, UGT1A3, UGT1A4, UGT1A1, UGT2B7 and UGT1A8 are involved in the conversion of ticagrelor to ticagrelor-O-glucuronide with UGT1A9 showing highest catalytic activity. The results were further supported by the inhibition studies on ticagrelor glucuronidation with typical UGT inhibitors in pooled HLM and HIM. Little or no inhibition of UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A9 and UGT2B7 by ticagrelor and ticagrelor-O-glucuronide was noted. Ticagrelor-O-glucuronide also exhibited limited inhibitory effects toward CYP2C8, CYP2D6 and CYP3A4. In contrast, ticagrelor-O-glucuronide weakly inhibited CYP2B6, CYP2C9 and CYP2C19 activity with apparent IC50 values of 45.0, 20.0 and 18.8 μM, respectively. The potential of ticagrelor-O-glucuronide to cause drug-drug interactions warrant further study.
研究领域:
药理学
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药物代谢
·
临床药学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 39
·22966-22971
·
IF 3.119
Ling Xiao,Dehui Chi,Guiju Sheng,Wenjuan Li,Penghui Lin,Sicheng Liang,Liangliang Zhu,Peipei Dong
UDP-glucuronosyltransferases (UGTs) and β-glucuronidase (GUS) catalyze entirely distinct metabolism reactions. UGTs are responsible for the glucuronidation of a variety of drugs, endogenous and environmental chemicals, whereas GUS hydrolyzes glucuronides and liberates the parent substrates. Information on the overlap of ligand selectivity between UGT and GUS is essential for exploring the pharmacological or toxicological effects of the inhibitors of these two metabolic enzymes. This study is conducted to test whether UGTs and GUS share common ligands, by investigating the inhibitory effects towards E. coli GUS by a series of UGT typical substrates and inhibitors. Results showed that three typical ligands of UGTs, including two specific substrates (estradiol and trifluoperazine, E2 and TFP) and one selective inhibitor (magnolol, Mag), can inhibit the activity of GUS. Kinetic assays indicated that all the three UGT specific chemicals displayed competitive inhibition, with Ki values of 31.4 (E2), 56.9 (TFP), and 16.6 μM (Mag). Docking studies further revealed that the three chemicals can enter the active sites of GUS by forming contacts with residues Glu-413, Trp-549, Asp-163, Tyr-472, Arg-562, or bound water. Our study indicates that ligand selectivity overlaps between UGTs and GUS, and some chemicals can act as co-inhibitors of these two metabolic enzymes. The pharmacological or toxicological effects of those co-inhibitors require further investigations.
研究领域:
药理学
·
生物化学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
XENOBIOTICA
·
2018
·
IF 1.857
Li Wang,Xiaodan Hong,Zhihong Yao,Yi Dai,Guoping Zhao,Zifei Qin,Baojian Wu,Frank J. Gonzalez,Xinsheng Yao
1. Icaritin is a natural flavonoid with anti-osteoporosis activity. This study aimed to characterize icaritin glucuronidation by pooled human liver microsomes (HLM) and pooled human intestine microsomes (HIM), and to determine the contribution of individual UDP-glucuronosyltrans-ferase (UGT) enzyme to icaritin glucuronidation.2. Glucuronidation rates were determined by incubating icaritin with uridine diphosphate glucuronic acid (UDPGA)-supplemented microsomes. Kinetic parameters were derived by appropriate model fitting. Relative activity factors and activity correlation analysis were performed to identify main UGT isoforms.3. UGT1A3, 1A7, 1A8, 1A9 and 2B7 were mainly responsible for catalyzing the formation of two glucuronides (G1 and G2). Icaritin 3-O-glucuronidation (G1) was significantly correlated with Chenodeoxycholic acid (CDCA) glucuronidation (r = 0.787, p = 0.002), propofol glucuronidation (r = 0.661, p = 0.019) and Zidovudine (AZT) glucuronidation (r = 0.805, p = 0.002). Similarly, icaritin 7-O-glucuronidation (G2) was also correlated with CDCA glucuronidation (r = 0.640, p = 0.025), propofol glucuronidation (r = 0.592, p = 0.043) and AZT glucuronidation (r = 0.661, p = 0.019). In addition, UGT1A3, 1A9 and 2B7 contributed 37.5, 33.8 and 21.3% for G1 in pooled HLM, respectively. Also, UGT1A3, 1A9 and 2B7 contributed 34.3, 20.0 and 8.6% for G2 in pooled HLM, respectively.4. Icaritin was subjected to significant glucuronidation, wherein UGT1A3, 1A7, 1A8, 1A9 and 2B7 were main contributing enzymes.
研究领域:
药理学
·
生物化学
·
药物代谢
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Foods
·
2025
·Vol. 14
·期 17
·2970
·
IF 5.1
Yuxin Shi,Mingna Dong,Xuhui Lei,Zhiying Xu,Jiyan Sun,Yingying Zhao,Yichao Ma,Hui Zhou,Shu Liu,Yunhai He,Qiukuan Wang,Dandan Ren
This study investigated how different extraction parts of raw materials and different flocculation methods affect the extraction yield, structure, and properties of sodium alginate. The aim was to improve the quality of sodium alginate and provide theoretical guidance for upstream enterprises. In this study,Lessonia nigrescens(LN) was used as a raw material. The alkali treatment conditions were optimized. The optimal extraction conditions were determined to be a 2% sodium carbonate concentration, a duration of 4 h, a material-to-liquid ratio of 1:40, and a temperature of 60 °C, achieving an extraction yield of 43.03%. LN was categorized into blades, stipes, holdfasts, and whole seaweed for comparative analysis, and sodium alginate was flocculated using the acid, calcium, and ethanol methods. Structural and physicochemical analyses showed that the mannuronic acid/guluronic acid (M/G) ratios of the twelve sodium alginate samples ranged from 5.73 to 8.76. The LN part had a greater influence on the M/G ratio than the flocculation method. The relative molecular weight (2343–3074 kDa) and viscosity (170–331 mPa·s) exhibited consistent trends. For the same part, the effect of the flocculation method on the molecular weight followed the order ethanol > acid > calcium. The physicochemical properties of the extracted sodium alginate met the requirements specified in the physicochemical index standard GB 1886.243-2016 of China.
研究领域:
海洋多糖化学
·
食品科学与技术
·
生物高分子提取与表征
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Nutrition
·
2021
·
IF 6.576
Yu Wantong,Cui Jiefen,Zhao Shaojie,Feng Liping,Wang Yanqi,Liu Junmei,Zheng Jinkai
Not-from-concentrate (NFC) juice is popular with consumers due to its similarity to fresh fruit juice in taste, flavor, and beneficial nutrients. As a commonly used technology in fruit juice production, high-pressure homogenization (HPH) can enhance the commercial value of juice by improving the color, flavor, taste, and nutrient contents. In this study, the effects of HPH on the pectin structural properties and stability of NFC orange juice were investigated. The correlations between HPH-induced changes in the structure of pectin and the stability of orange juice were revealed. Compared with non-homogenized orange juice, HPH increased the galacturonic acid (GalA) content and the linearity of pectin, while decreasing the molecular weight (Mw), pectin branching, and rhamnogalacturonan (RG) contribution, and cracks and pores of different sizes formed on the surface of pectin, implying depolymerization. Meanwhile, with increasing pressure and number homogenization of passes, HPH effectively improved the stability of NFC orange juice. HPH can effectively prevent the stratification of orange juice, thereby promoting consumer acceptance and endowing a higher commercial value. The improvement of the stability of NFC orange juice by HPH was related to the structural properties of pectin. Turbidity was significantly (P < 0.01) positively correlated with GalA and pectin linearity, but was significantly (P < 0.01) negatively correlated with Mw, RG contribution, and pectin branching. Modification of pectin structure can improve the stability of NFC orange juice. In this work, the relationship between the pectin structure and stability of NFC orange juice is elucidated, providing a path toward improving consumer acceptance and enhancing the palatability and nutritional and functional qualities of orange juice. Manufacturers can use this relationship to modify pectin directionally and produce high-quality NFC orange juice beverages.
研究领域:
食品科学
·
化学工程
·
饮料技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）