Dereplication of calystegines in food plants and wild Solanum Brazilian fruits.

Calystegines are potent glycosidase inhibitors with therapeutic potential and are constituents of food and feed with potential toxic effects. This study aims to target calystegines and other nitrogenous substances in food plants. Hydroalcoholic extracts from Solanum tuberosum, Ipomoea batatas, S. lycocarpum, and fruit from S. lycopersicum, S. aethiopicum, S. paniculatum, S. crinitum, and S. acanthodes were analyzed by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using an acidic HILIC column. The dereplication approach included data processing using MZMine2, FBMN-GNPS, and structure elucidation and interpretation of the organized data. The calystegines A3, A5, B2, and C1 were identified, and several potential new calystegine analogues: three may correspond to new calystegines of the A-group, one glycosyl derivative of calystegine A3, and two glycosyl derivatives of the B-group. These findings help to direct the search for new calystegines. In addition, the dereplication approach enabled the annotation of 22 other nitrogen compounds.

Residue Effect-Guided Design: Engineering of S. Solfataricus ß-Glycosidase to Enhance Its Thermostability and Bioproduction of Ginsenoside Compound K.

ß-Glycosidase from Sulfolobus solfataricus (SS-BGL) is a highly effective biocatalyst for the synthesis of compound K (CK) from glycosylated protopanaxadiol ginsenosides. In order to improve the thermal stability of SS-BGL, molecular dynamics simulations were used to determine the residue-level binding energetics of ginsenoside Rd in the SS-BGL-Rd docked complex and to identify the top ten critical contributors. Target sites for mutations were determined using dynamic cross-correlation mapping of residues via the Ohm server to identify networks of distal residues that interact with the key binding residues. Target mutations were determined rationally based on site characteristics. Single mutants and then recombination of top hits led to the two most promising variants SS-BGL-Q96E/N97D/N302D and SS-BGL-Q96E/N97D/N128D/N302D with 2.5-fold and 3.3-fold increased half-lives at 95 °C, respectively. The enzyme activities relative to those of wild-type for ginsenoside conversion were 161 and 116%, respectively..

Lavandula stoechas L. subsp. stoechas, a New Herbal Source for Ursolic Acid: Quantitative Analysis, Purification and Bioactivity Studies.

In this study, methanol, ethanol, methanol-dichloromethane (1 : 1, v/v), acetone, ethyl acetate, diethyl ether, and chloroform extracts of lavender (Lavandula stoechas L. subsp. stoechas) were prepared by maceration, and the ursolic acid contents in the extracts were determined quantitatively by HPLC analyses. The present results show that the methanol-dichloromethane (1 : 1, v/v) solvent system is the most efficient solvent system for the extraction of ursolic acid from the plant sample with the highest yield (2.22 g/100 g plant sample). In the present study, a new practical method for the isolation of ursolic acid from polar extracts was also demonstrated for the first time. The inhibition effects of the extracts and ursolic acid were also revealed on α-glycosidase, acetylcholinesterase, butyrylcholinesterase, and human carbonic anhydrase I and II enzymes by determining IC50 values for the first time. The extracts and ursolic acid acted as potent antidiabetic agents by strongly inhibiting the α-glycosidase activity, whereas they were found to be very weak neuroprotective agents. In view of the present results, L. stoechas and its major metabolite, ursolic acid, can be recommended as a herbal source to control postprandial blood sugar levels and prevent diabetes by delaying the digestion of starch in food.

Enzyme Inhibition and Antioxidant Activities of Asparagus officinalis L. and Analysis of Its Phytochemical Content by LC/MS/MS.

In the study, water, ethanol, methanol, dichloromethane, and acetone extracts of Asparagus officinalis L. were obtained by maceration. DPPH⋅, ABTS⋅+ , FRAP, and CUPRAC methods determined the antioxidant capacities of all extracts. Moreover, the in vitro effects of extracts on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carbonic anhydrase (CA)-I, CA-II and α-Glycosidase were investigated. At a 10 µg/ml concentration, the extract with the highest Fe3+ reduction capacity was ethanol (AE), and the extract with the highest Cu2+ reduction capacity was acetone (AA). AE for AChE (IC50 =21.19 µg/ml) and α-Glycosidase (IC50 : 70.00 µg/ml), methanol (AM) for BChE (IC50 =17.33 µg/ml), CA-I and II (IC50 =79.65 and 36.09 µg/ml, respectively) showed the most potent inhibition effect. The content analysis of acetone extract was performed with LC/MS-MS, the first three phytochemicals found most were p-Coumaric acid, rutin, and 4-hydroxybenzoic acid (284.29±3.97, 135.39±8.19, and 102.06±5.51 µg analyte/g extract, respectively).

Engineered Glycosidase for Significantly Improved Production of Naturally Rare Vina-Ginsenoside R7.

Ginsenosides are the main bioactive ingredients in plants of the genus Panax. Vina-ginsenoside R7 (VG-R7) is one of the rare high-value ginsenosides with health benefits. The only reported method for preparing VG-R7 involves inefficient and low-yield isolation from highly valuable natural resources. Notoginsenoside Fc (NG-Fc) isolated in the leaves and stems of Panax notoginseng is a suitable substrate for the preparation of VG-R7 via specific hydrolysis of the outside xylose at the C-20 position. Here, we first screened putative enzymes belonging to the glycoside hydrolase (GH) families 1, 3, and 43 and found that KfGH01 can specifically hydrolyze the ß-d-xylopyranosyl-(1 → 6)-ß-d-glucopyranoside linkage of NG-Fc to form VG-R7. The I248F/Y410R variant of KfGH01 obtained by protein engineering displayed a kcat/KM value (305.3 min-1 mM-1) for the reaction enhanced by approximately 270-fold compared with wild-type KfGH01. A change in the shape of the substrate binding pockets in the mutant allows the substrate to sit closer to the catalytic residues which may explain the enhanced catalytic efficiency of the engineered enzyme. This study identifies the first glycosidase for bioconversion of a ginsenoside with more than four sugar units, and it will inspire efforts to investigate other promising enzymes to obtain valuable natural products.

Anti-Alzheimer's Disease Effect of Polysaccharides from Zanthoxyli Pericarpium and Analysis of Its Structural Characteristics by Sugar Spectrum / 中国实验方剂学杂志

ObjectiveThe therapeutic effect of polysaccharides from Zanthoxyli Pericarpium on Alzheimer's disease（AD） was evaluated through establishing a mouse model of AD， and the structural characteristics of the polysaccharides was analyzed by sugar spectrum. MethodThe AD model of mice with rapid aging was established by intraperitoneal injection of D-galactose combined with gavage of aluminum trichloride， and the learning and memory ability of mice was evaluated by Morris water maze test， the histopathological status of brain and neuronal damage were observed by hematoxylin-eosin（HE） staining and Nissl staining. After hydrolysis of polysaccharides from Zanthoxyli Pericarpium with acid and different glycosidases， the characteristics of hydrolysates were analyzed by high performance thin layer chromatography（HPTLC） and fluorescence assisted carbohydrate gel electrophoresis（PACE）. HPTLC chromatography was performed on a silica gel 60 plate with sampling volume of 5 μL， developing solvent of ethyl acetate-glacial acetic acid-water（2∶2∶1）， developing twice， aniline-diphenylamine-phosphoric acid solution as chromogenic agent， and heating at 105 ℃ for 10 min， and then observed under sunlight. PACE experimental conditions were 34% separation gel and 8% concentration gel， electrophoresis buffer was 0.1 mol·L-1 tris（hydroxymethyl） aminomethane（Tris）-boric acid buffer（pH 8.2）. Electrophoresis was carried out at 0 ℃ and the loading amount was 3-6 μL. The sample ran to the front of the gel with a constant current of 15 mA， and imaged under ultraviolet 365 nm. ResultThe results of Morris water maze test showed that polysaccharides from Zanthoxyli Pericarpium significantly improved the learning and memory ability of AD model mice， shortened the escape latency， and significantly increased the number of crossing and the residence time in the target quadrant. The results of histopathological experiments showed that polysaccharides from Zanthoxyli Pericarpium could improve the pathological conditions and neuronal damage in the CA1 and CA3 regions of hippocampus of AD mice， and the number of Nissl corpuscles was significantly increased. The results of sugar spectrum analysis showed that the results of HPTLC and PACE analysis were basically consistent， polysaccharides from Zanthoxyli Pericarpium could be mainly hydrolyzed into small molecular sugars by cellulase and pectinase， indicating that they mainly contained β-1，4-glucosidic bond and α-1，4-galacturonic acid glycosidic bond， and could be slightly hydrolyzed by glucanase， β-galactosidase and β-mannase， indicating that they contained only a small amount of α-1，6-glucosidic bond， β-galactosidic bond， β-1，4-mannosidic bond. ConclusionPolysaccharides from Zanthoxyli Pericarpium has obvious therapeutic effect on AD mice， and its structure mainly contains β-1，4-glucosidic bond and α-1，4-galacturonic acid glycosidic bond， which can provide a reference for the structural analysis of traditional Chinese medicine polysaccharides.

Alternative method for microenzymatic inhibition activities monitoring from Baccharis trimera extracts by CZE-UV.

INTRODUCTION: Capillary zone electrophoresis with direct UV detection (CZE-UV) was used to investigate the hypothesis about the extract of Baccharis trimera enzymatic activities as an analytical approach to monitoring the phenomenon. OBJECTIVE: The aim of this work was to investigate enzymatic bioactivities of the hydroalcoholic and infusion extracts of B. trimera through screening evaluation of the inhibition of the enzymes acetylcholinesterase (AChE) and α-glycosidase (α-GLY). METHOD: An alternative approach using CZE-UV to hydroalcoholic and infusion extracts of B. trimera monitoring was applied to evaluate the inhibition ability of the enzymes AChE and α-GLY. The result of the reaction of acetylthiocholine (AThCh) with AChE was thiocholine (TCh) and acetic acid, and from the amount of TCh generated, the AChE inhibition was calculated. For the inhibition study of the two enzymes, the reactions of the extracts were optimised to be performed in situ, inside the capillary column, and the introduction of the solutions was performed through ordered sequential plug injections. RESULTS: Samples extracted with 70% ethanol presented 7.80% inhibition for AChE and 0.51% for α-GLY, while samples extracted with 96% ethanol resulted in 6.89% inhibition for AChE and no inhibition activity for α-GLY. CONCLUSION: In the present work, the potentialities of CZE-UV for the study of hydroalcoholic and infusion extracts of B. trimera were demonstrated. The experimental results were useful for the calculation of the percentage of the inhibition activities of the AChE and α-GLY enzymes.

Characterization of a thermostable, protease-tolerant inhibitor of α-glycosidase from carrot: A potential oral additive for treatment of diabetes.

Inhibiting α-glucosidase activity is important in controlling postprandial hyperglycemia and, thus, helping to manage type-2 diabetes mellitus (T2DM). In the present study, we purified a hypothetical protein of carrots called DCHP (Daucus Carrot hypoglycemic peptide), and their inhibitory effects on α-glucosidase, as well as related mechanisms, were investigated. The recombinant DCHP protein with a molecular weight of 8 kDa showed strong inhibitory activity against α-glycosidase and maintained good stability in solution. DCHP exhibited no inhibitory activity but was tolerant to trypsin and chymotrypsin. Cellular experiments demonstrated that glucose consumption and lactic acid production increased rapidly when treated with DCHP in Caco-2 and HepG2 cells. DCHP crystal was generated, and the crystal structure, which was similar to that of rBTI and consisted of a central α-helix and a two-stranded ß-sheet with a unique loop region. The interaction between DCHP and α-glycosidase was investigated by molecular docking and site-directed mutation, which revealed that Glu43, Pro46, Thr47 Thr48 and Gln49 are the key residues in DCHP that inhibit α-glycosidase activity. This work provides potential bioactive peptides as functional foods or nutraceutical supplements in preventing and managing T2DM.

Consumption of the Syrian mesquite plant (Prosopis farcta) fruit and seed lyophilized extracts may have both protective and toxic effects in STZ-induced diabetic rats.

The aim of study was to investigate the antidiabetic and antioxidant properties of extracts obtained from dried Prosopis farcta fruit and seeds against streptozotocin-induced diabetes in rats. According to the results, glucose, haemoglobin A1c, α-glycosidase activity, liver and kidney damage biomarkers, and malondialdehyde contents of all of the diabetic groups were found to have increased significantly according to the control group. Furthermore, the insulin and C-peptide secretions increased, and liver malondialdehyde level decreased, which were determined as the result of fluctuations in the antioxidant enzyme activities with a dose of 400 mg/kg fruit extract, while seed extract dosages of 100 and 400 mg/kg caused an increase in hepatic demage biomarkers. It was concluded that fruit extract may have insulin secretion stimulating and lipid peroxidation inhibitory effects, whereas seed extract might have caused hepatocyte damage changes to the transport functions and membrane permeability of these cells, thus causing enzymes to leak.

γ-Glutamyl-ß-phenylethylamine, a novel α-glucosidase and α-amylase inhibitory compound from Termitomyces robustus, an edible Nigerian mushroom.

Termitomyces species are known edible mushrooms in Nigeria, believed to have exceptional culinary and nutraceutical properties. Methanol extract from fruiting bodies of Termitomyces robustus was evaluated for antidiabetic activity using in vitro α-amylase and α-glucosidase assays. The isolation and structural elucidation of metabolites from the T. robustus extract afforded five compounds including a new natural product γ-glutamyl-ß-phenylethylamine 3 and four known phenyl derivatives: tryptophan 1, 4-hydroxyphenylacetic acid 2, 4-hydroxyphenylpropionic acid 4, and phenyllactic acid 5. Structures were elucidated from analyses of spectroscopic data (1 D and 2 D NMR, HRESIMS) and all isolated compounds were tested for α-amylase and α-glycosidase inhibitory activity. The in vitro assay established crude extract to possess α- amylase and α-glucosidase inhibition with IC50 of 78.05 µg/mL and 86.10 µg/mL, respectively. The isolated compounds compared favourably with the standard drug, acarbose with IC50 ranging from 6.18-15.08 µg/mL and 18.28-44.63 µg/mL for α-amylase and glucosidase, respectively.

Lyophyllin, a Mushroom Protein from the Peptidase M35 Superfamily Is an RNA N-Glycosidase.

Ribosome-inactivating proteins (RIPs) hydrolyze the N-glycosidic bond and depurinate a specific adenine residue (A-4324 in rat 28S ribosomal RNA, rRNA) in the conserved α-sarcin/ricin loop (α-SRL) of rRNA. In this study, we have purified and characterized lyophyllin, an unconventional RIP from Lyophyllum shimeji, an edible mushroom. The protein resembles peptidase M35 domain of peptidyl-Lys metalloendopeptidases. Nevertheless, protein either from the mushroom or in recombinant form possessed N-glycosidase and protein synthesis inhibitory activities. A homology model of lyophyllin was constructed. It was found that the zinc binding pocket of this protein resembles the catalytic cleft of a classical RIP, with key amino acids that interact with the adenine substrate in the appropriate positions. Mutational studies showed that E122 may play a role in stabilizing the positively charged oxocarbenium ion and H121 for protonating N-3 of adenine. The tyrosine residues Y137 and Y104 may be used for stacking the target adenine ring. This work first shows a protein in the peptidase M35 superfamily based on conserved domain search possessing N-glycosidase activity.

Antidiabetic Properties of Curcumin: Insights on New Mechanisms.

Plant extracts have been used to treat a wide range of human diseases. Curcumin, a bioactive polyphenol derived from Curcuma longa L., exhibits therapeutic effects against diabetes while only negligible adverse effects have been observed. Antioxidant and anti-inflammatory properties of curcumin are the main and well-recognized pharmacological effects that might explain its antidiabetic effects. Additionally, curcumin may regulate novel signaling molecules and enzymes involved in the pathophysiology of diabetes, including glucagon-like peptide-1, dipeptidyl peptidase-4, glucose transporters, alpha-glycosidase, alpha-amylase, and peroxisome proliferator-activated receptor gamma (PPARγ). Recent findings from in vitro and in vivo studies on novel signaling pathways involved in the potential beneficial effects of curcumin for the treatment of diabetes are discussed in this review.

LC-HRMS Profiling and Antidiabetic, Anticholinergic, and Antioxidant Activities of Aerial Parts of Kinkor (Ferulago stellata).

Kinkor (Ferulago stellata) is Turkish medicinal plant species and used in folk medicine against some diseases. As far as we know, the data are not available on the biological activities and chemical composition of this medicinal plant. In this study, the phytochemical composition; some metabolic enzyme inhibition; and antidiabetic, anticholinergic, and antioxidant activities of this plant were assessed. In order to evaluate the antioxidant activity of evaporated ethanolic extract (EEFS) and lyophilized water extract (WEFS) of kinkor (Ferulago stellata), some putative antioxidant methods such as DPPH· scavenging activity, ABTS•+ scavenging activity, ferric ions (Fe3+) reduction method, cupric ions (Cu2+) reducing capacity, and ferrous ions (Fe2+)-binding activities were separately performed. Furthermore, ascorbic acid, BHT, and α-tocopherol were used as the standard compounds. Additionally, the main phenolic compounds that are responsible for antioxidant abilities of ethanol and water extracts of kinkor (Ferulago stellata) were determined by liquid chromatography-high-resolution mass spectrometry (LC-HRMS). Ethanol and water extracts of kinkor (Ferulago stellata) demonstrated effective antioxidant abilities when compared to standards. Moreover, ethanol extract of kinkor (Ferulago stellata) demonstrated IC50 values of 1.772 µg/mL against acetylcholinesterase (AChE), 33.56 ± 2.96 µg/mL against α-glycosidase, and 0.639 µg/mL against α-amylase enzyme respectively.

Synthesis and Evaluation of Novel Iminosugars Prepared from Natural Amino Acids.

Cyclopropanated iminosugars have a locked conformation that may enhance the inhibitory activity and selectivity against different glycosidases. We show the synthesis of new cyclopropane-containing piperidines bearing five stereogenic centers from natural amino acids l-serine and l-alanine. Those prepared from the latter amino acid may mimic l-fucose, a natural-occurring monosaccharide involved in many molecular recognition events. Final compounds prepared from l-serine bear S configurations on the C5 position. The synthesis involved a stereoselective cyclopropanation reaction of an α,ß-unsaturated piperidone, which was prepared through a ring-closing metathesis. The final compounds were tested as possible inhibitors of different glycosidases. The results, although, in general, with low inhibition activity, showed selectivity, depending on the compound and enzyme, and in some cases, an unexpected activity enhancement was observed.

In vitro α-glycosidase and urease enzyme inhibition profile of some selected medicinal plants of Pakistan.

The current study aims at exploring enzyme inhibition of four species of medicinal herbs, namely Senna bicapsularis, Thevetia peruviana, Nerium oleander and Vinca major. Plant selection was done on the basis of their therapeutic uses by local practitioners. The crude methanolic extracts of these plants were tested for their α-glycosidase and urease enzyme inhibition potential. The observed urease inhibitory potential for the crude extract of S. bicapsularis, T. peruviana and N. oleander were 8.3 ± 0.33 µg, 6.98 ± 0.98 µg and 9.56 ± 1.43 µg, respectively while the V. major did not show any inhibition. In addition, the IC50 value for Thiourea was 22.3 ± 1.14 µg. The crude extracts of S. bicapsularis, T. peruviana, N. oleander, V. major were shown to inhibit α-glycosidase activity with an IC50 value of 630.3 ± 0.03 µg, 700.7 ± 2.43 µg, 430.4 ± 3.97 µg, and the standard (acarbose) 880 ± 1.03  µM, respectively. Based on the TLC profile, the extract of S. bicapsularis was subjected to column chromatography and the major component named rhein (1) was identified. Compound 1 exhibited excellent urease and α-glycosidase inhibitory activity with an IC50 value of 7.4 ± 0.32 and 622.3 ± 1.03 µM, respectively.

A new pyrano coumarin from Clausena excavata roots displaying dual inhibition against α-glucosidase and free radical.

A new pyrano coumarin, identified as excavatin A (1) together with two known compounds nordentatin (2) and binorpocitrin (3) was isolated from the 95% EtOH extract of Clausena excavata. All structures were elucidated by using spectroscopy methods such as extensive NMR and HR-FAB-MS spectrometry. All the isolated compounds were tested on antidiabetes activity by using α-glucosidase inhibition assay and the antioxidant activity by DPPH assay. Compounds 1-3 showed antioxidant activity with IC50 values 0.286, 0.02, 0.278 mM. Among them, 2 exhibited inhibition activity against maltase (IC50 5.45 µM) and sucrase (IC50 43.57 µM). However, compounds (1) and (3) displayed inhibition on yeast α-glucosidase with IC50 values 1.92 and 5.58 mM.[Figure: see text].

Synthesis of nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds - Determination of their carbonic anhydrase, acetylcholinesterase, butyrylcholinesterase and α-glycosidase inhibition properties.

Sulfur-containing pyrroles (1-3), tris(2-pyridyl)phosphine(selenide) sulfide (4-5) and 4-benzyl-6-(thiophen-2-yl)pyrimidin-2-amine (6) were synthesized and characterized by elemental analysis, IR and NMR spectra. In this study, the synthesized compounds of nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds (1-6) were evaluated against the human erythrocyte carbonic anhydrase I, and II isoenzymes, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase enzymes. The synthesized heterocyclic compounds showed IC50 values in range of 33.32-60.79 nM against hCA I, and 37.05-66.64 nM against hCA II closely associated with various physiological and pathological processes. On the other hand, IC50 values were found in range of 13.13-22.21 nM against AChE, 0.54-31.22 nM against BChE, and 13.51-26.55 nM against α-glycosidase as a hydrolytic enzyme. As a result, nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds (1-6) demonstrated potent inhibition profiles against indicated metabolic enzymes. Therefore, we believe that these results may contribute to the development of new drugs particularly in the treatment of some global disorders including glaucoma, Alzheimer's disease and diabetes.

Secondary metabolites of Helichrysum plicatum DC. subsp. plicatum flowers as strong carbonic anhydrase, cholinesterase and α-glycosidase inhibitors.

Helichrysum plicatum species are used in Turkish folk medicine as lithagogue, diuretic, and nephritic. Research on the methanol (MeOH) extract of flowers of H. plicatum DC. subsp. plicatum resulted in the isolation of eight known compounds (1-8). The chemical structures of the compounds were determined as ß-sitosterol (1), apigenin (2), nonacosanoic acid (3), astragalin (4), ß-sitosterol-3-O-ß-D-glucopyranoside (5), helichrysin A (6), helichrysin B (7), and isosalipurposide (8) by spectroscopic and chromatographic/spectrometric methods, including 1D and 2D nuclear magnetic resonance and liquid chromatography-tandem mass spectrometry. Nonacosanoic acid (3) was isolated for the first time from H. plicatum DC. subsp. plicatum. The MeOH extract and isolated compounds were evaluated for their in vitro human carbonic anhydrase I (hCAI) and II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase inhibitory activities. The IC50 values of H. plicatum DC. subsp. plicatum MeOH extract for hCAI, hCAII, AChE, BChE, and α-glycosidase were found to be 77.87, 52.90, 115.50, 117.46, and 81.53 mg/mL, respectively. The compounds showed IC50 values of 1.43-4.47, 1.40-4.32, 1.69-2.90, 1.09-3.89, and 1.61-3.80 µM against hCAI, hCAII, AChE, BChE, and α-glycosidase, respectively. In summary, H. plicatum DC. subsp. plicatum secondary metabolites demonstrated strong inhibitory effects especially against hCAI and hCAII, whereas the MeOH extract showed a weak inhibitory effect on all enzymes.

Synthesis and Therapeutic Applications of Iminosugars in Cystic Fibrosis.

Iminosugars are sugar analogues endowed with a high pharmacological potential. The wide range of biological activities exhibited by these glycomimetics associated with their excellent drug profile make them attractive therapeutic candidates for several medical interventions. The ability of iminosugars to act as inhibitors or enhancers of carbohydrate-processing enzymes suggests their potential use as therapeutics for the treatment of cystic fibrosis (CF). Herein we review the most relevant advances in the field, paying attention to both the chemical synthesis of the iminosugars and their biological evaluations, resulting from in vitro and in vivo assays. Starting from the example of the marketed drug NBDNJ (N-butyl deoxynojirimycin), a variety of iminosugars have exhibited the capacity to rescue the trafficking of F508del-CFTR (deletion of F508 residue in the CF transmembrane conductance regulator), either alone or in combination with other correctors. Interesting results have also been obtained when iminosugars were considered as anti-inflammatory agents in CF lung disease. The data herein reported demonstrate that iminosugars hold considerable potential to be applied for both therapeutic purposes.

Structural characterization and α-glycosidase inhibitory activity of a novel polysaccharide fraction from Aconitum coreanum.

α-Glycosidase is an essential target for the management of postprandial serum glucose in diabetic patients. Therefore, the interest has been growing in the screening of α-glycosidase inhibitor from natural resource. In the present study, the structure and α-glycosidase inhibitory activity of a polysaccharide (named as ACPP-1) from Aconitum coreanum were investigated. Based on the results from high performance gel permeation chromatography, GC-MS and 1D/2D nuclear magnetic resonance spectroscopy, ACPP-1 was a highly-linear polysaccharide with a molecular weight of 34.0 kD and containing over 90 % of glucose. It was composed of (1→4)-α-d-Glcp and α-Araf. ACPP-1 exhibited a dose-dependent inhibitory eff ;ect against α-glycosidase activity in vitro and the IC50 value was ∼0.8 mg/mL. In oral starch tolerance test, treatment with ACPP-1 (800 mg/kg) significantly improved the starch tolerance in mice. Taken together, this study provided a potential intervention and management for postprandial hyperglycemia by the polysaccharide fraction from A. coreanum.