Oleanane-type triterpene saponins from the bark of Aralia elata and their NF-κB inhibition and PPAR activation signal pathway

Two new oleanane-type triterpene saponins, tarasaponin IV (1) and elatoside L (2), and four known; stipuleanoside R(2) (3), kalopanax-saponin F (4), kalopanax-saponin F methylester (5), and elatoside D (6) were isolated from the bark of Aralia elata. Kalopanax-saponin F methyl ester was isolated from nature for the first time. Their chemical structures were elucidated using the chemical and physical methods as well as good agreement with those of reported in the literature. Oleanane-type triterpene saponins are the main component of A. elata. All compounds were investigated the anti-inflammatory activity. We measured their inhibition of NF-κB and activation of PPARs activities in HepG2 cells using luciferase reporter system. As results, compounds 2 and 4 were found to inhibit NF-κB activation stimulated by TNFα in a dose-dependent manner with IC(50) values of 4.1 and 9.5 μM, respectively, when compared with that of positive control, sulfasalazine (0.9 μM). Compounds 2 and 4 also inhibited TNFα-induced expression of iNOS and COX-2 mRNA. Furthermore, compounds 1-6 were evaluated PPAR activity using PPAR subtype transactivation assays. Among of them, compounds 4-6 significantly increased PPARγ transactivation. However, compounds 4-6 did not activate in any other PPAR subtypes.     

Petiolins J–M,prenylated acylphloroglucinols from Hypericum pseudopetiolatum var. kiusianum

Four new prenylated acylphloroglucinols, petiolins J?M (1?4), were isolated from aerial parts of Hypericum pseudopetiolatum var. kiusianum, and the structures were elucidated by spectroscopic data and a single-crystal X-ray diffraction analysis. Petiolin J (1) exhibited antimicrobial activity.     

Antioxidant, α-glucosidase inhibitory and anti-inflammatory effects of aerial parts extract from Korean crowberry (Empetrum nigrum var. japonicum)

Crowberry (Empetrum nigrum L.) is a wild berry commonly found in the northern hemisphere. Crowberry fruits have been suggested as good resources for functional applications in the cosmetic and pharmaceutical industries, but the high polyphenolic content in crowberry leaves also indicates crowberry aerial parts as potential dietary health supplements. In this study, therefore, the biological activities of the aerial parts of Korean crowberry (E. nigrum var. japonicum) were investigated. Antioxidant activity was measured by three different assays on DPPH free radical scavenging, reducing power, and total antioxidant capacities. Dose-dependent antioxidant activities were exhibited by crude methanol extract and its fractions, suggesting that the crude methanol extract and EtOAc fraction possessed strong antioxidant activities and capacities. In addition, the crude methanol extract and EtOAc strongly inhibited α-glucosidase activity and suppressed the secretion of pro-inflammatory mediator and nitrite oxide from LPS-stimulated RAW 264.7 cells. These findings provide valuable evidence for the potential of such parts as good dietary sources of natural antioxidant, α-glucosidase inhibitory, and anti-inflammatory components, suggesting that using the non-edible parts (e.g., leaves and stems) of crowberry can be a potential natural avenue for improving human health.     

6α-Acetoxy-16β,22-dihydroxyhopan-24-oic acid,a triterpene from the fern Notholaena candida var. copelandii

Farinose exudates on fronds of gymnogrammoid ferns generally consist of flavonoid aglycones. In Notholaena candida var. copelandii a new triterpene was found as a major component of the farina besides galangin 3-methylether and kaempferol 3-methylether. Extensive mass spectral and NMR studies revealed this triterpene to be a new natural product, 6α-acetoxy-16β,22-dihydroxyhopan-24-oic acid.     

Starfish saponins—XI. Isolation and partial characterization of the saponins from the starfish Marthasterias glacialis

• 1.1. The saponin mixture isolated from Marthasterias glacialis was resolved through a series of chromatographic steps into four principal individual components, named marthasteroside A₁, A₂, B and C.
• 2.2. The isolated sulphate steroidal glycosides were characterized by ¹H-NMR, ¹³C-NMR, Fast Atom Bombardment mass spectrometry and GLC analysis of the sugars after acid hydrolysis.
• 3.3. Marthasteroside A₁ and A₂ contained the aglycone thornastrol A and six sugar units. The second group of compounds, marthasteroside B and C, contained five sugar units; the aglycone of marthasteroside B was identified as marthasterone, while that of marthasteroside C was identified as dihydromarthasterone. In all compounds the sulphate group is attached at C-3 of the steroid.

     

Zizimauritic acids A–C,three novel nortriterpenes from Ziziphus mauritiana

Zizimauritic acids A–C (1–3), three novel nortriterpenes with a unique A-nor-E-seco spiro-lactone ceanothane-type triterpene skeleton, together with 3 known triterpenes ceanothenic acid (4), betulinic acid (5), and ceanothic acid (6), were isolated from the roots of Ziziphus mauritiana. Compounds 1–4 showed cytotoxicities with the IC₅₀ values ranging from 5.05 to 11.94 μg/ml, and compounds 1 and 3 showed an inhibitory effect on the growth of Staphylococcus aureus with the IC₅₀ values 2.17 and 12.79 μg/ml. A plausible biosynthetic pathway of compounds 1-3 was proposed.     

Potent α-glucosidase inhibitors from the roots of Panax japonicus C. A. Meyer var. major

Bioassay-guided fractionation of the CHCl₃ soluble portion of the roots of Panax japonicus C. A. Meyer var. major afforded an active fraction with inhibitory activity against baker’s yeast α-glucosidase with an IC₅₀ value 1.02 mg/mL. Furthermore, the active fraction isolated contained three previously unreported polyacetylenes, designated panaxjapynes A–C, together with 11 other compounds, including four polyacetylenes, five phenolic compounds, a sesquiterpenoid, and a sterol glucoside. The structures of the compounds were elucidated by spectroscopic and chemical methods. Compared with the control acarbose (IC₅₀ 677.97 μM), six compounds were shown to be more potent α-glucosidase inhibitors with IC₅₀ values in the range 22.21–217.68 μM.     

Chemical compositions by using LC–MS/MS and GC–MS and antioxidant activities of methanolic extracts from leaf and flower parts of Scabiosa columbaria subsp. columbaria var. columbaria L.

The members of the Scabiosa genus are one of the traditional medicinal plants used in the treatment of many diseases, in particular the treatment of scabies. In this study, it was aimed to determine antioxidant activities and chemical composition of methanolic extracts of leaves and flowers of Scabiosa columbaria subsp. columbaria var. columbaria. The phenolic contents of both parts of the plant were analyzed by LC–MS/MS. A total of 6 phenolic compounds were determined and chlorogenic acid was the major compound in both flower and leaf parts of the plants, with 5936.052 µg/g and 8021.666 µg/g, respectively. 6 different methods were used to determine the antioxidant activity of the plant parts. Both leaf and flower parts of the plant showed high antioxidant activity in all tested methods and the antioxidant activity values of the leaf part were measured higher than those of the flower part for four tests. The methanol extracts of the plant parts was analyzed with GC–MS and number of the essential oil compounds in the leaf and flower parts were determined as 17 and 13, respectively. Linalool compound was also found to be common in both parts of the plant. The major compounds of the essential oils were identified as 4-Octadecenal (30.01%) in the flower and carvone (35.44%) in the leaf. In addition, terpene derivatives was determined as 90.32% of the highest essential oil group in the leaf, while this value was determined as 1.42% in the flower. For the flower, aromatics were determined as the main component group with 21.31%.     

Subunit compositions of trypsin inhibitors from tubers of taro, Colocasia antiquorum var. nymphaifolia?

Several trypsin inhibitors with different mobilities on polyacrylamide gel electrophoresis occur in the tubers of taro (Colocasia antiquorum), and they each have a dimeric molecular weight of 40,000. Of all the constituent subunits, molecular weight 20,000, of the taro trypsin inhibitor (TTI), three major subunit components were separated by chromatography on SP-Sephadex C-25 in 8 M urea, and they were named protomers alpha, beta, and gamma in the order of their elution from the SP-Sephadex column. After removal or dilution of the urea, the three protomers could be either reassociated individually or hybridized with each other to form dimeric inhibitors. All of the reassociated dimers were powerful inhibitors of trypsin. Among them, each dimer derived from protomers alpha and gamma was a weak inhibitor of chymotrypsin, whereas the dimer of protomer beta did not inhibit the enzyme. Therefore TTI is presumed to be a mixture of heterogeneous and homogenous dimers whose properties reflect those of their constituent protomers. It was also proved that the major three trypsin inhibitors (TTI-I, TTI-II, and TTI-III) previously isolated from taro tubers are composed of protomers alpha and gamma, i.e., TTI-II is a heterogeneous dimer of protomers alpha and gamma, and TTI-I and TTI-III are homogeneous dimers of protomers alpha and gamma, respectively. The molecular weight of a trypsin-TTI complex saturated with trypsin was found to be 79,000, suggesting the formation of a tetrameric complex.     

Chalcone glycosides from aerial parts of Brassica rapa L. ‘hidabeni’, turnip

A phytochemical investigation of the aerial parts of Brassica rapa L. ‘hidabeni’, turnip resulted in the isolation of three new chalcone glycosides, 4′-O-β-d-glucopyranosyl-4-hydroxy-3′-methoxychalcone (1), 4′-O-β-d-glucopyranosyl-3′,4-dimethoxychalcone (2) and 4,4′-di-O-β-d-glucopyranosyl-3′-methoxychalcone (3) along with three known glycosides. The structures of the three newly isolated chalcone glycosides were elucidated on the basis of 1D and 2D NMR and mass spectroscopy.     

A novel transglycosylating β-galactosidase from Enterobacter cloacae B5

A strain of Enterobacter cloacae B5 producing β-galactosidase with transglycosylation activity was isolated from the soil. Its freeze-thawed cells synthesized galacto-oligosaccharides with a high yield of 55% from 275 g/L lactose at 50 °C for 12 h. A novel β-galactosidase capable of glycosyl transfer was purified from this strain. It was a homotetramer with molecular mass of about 442 kDa. The optimal pH and temperature for hydrolysis activity on o-nitrophenyl-β-d-galactopyranoside (oNPGal) were 6.5–10.5 and 35 °C, respectively. The enzyme showed a wide range of acceptor specificity for transglycosylation and catalyzed glycosyl transfer from oNPGal to various chemicals such as galactose, glucose, fructose, arabinose, mannose, sorbose, rhamnose, xylose, cellobiose, sucrose, trehalose, melibiose, inositol, mannitol, sorbitol and salicin, resulting in novel saccharide yields ranging from 0.8% to 23.5%. A gene encoding the enzyme was cloned and the recombinant enzyme from Escherichia coli had similar transglycosylation activity to the natural enzyme.     

Pinus nigra Arn. var.gočensis,n. var.

Ohne Zusammenfassung     

Phragmalin-type limonoids with NF-κB inhibition from Chukrasia tabularis var. velutina

Chemical investigation on Chukrasia tabularis var. velutina led to the identification of eight new phragmalin-type limonoids (1–8), as well as 20 known analogues. Compounds 1–4 are a rare class of C-15-acyl phragmalin-type limonoids, and particularly compounds 2–4 also possess a δ-lactone ring formed between C-16 and C-30. All the isolates were evaluated for inhibitory effects on NF-κB production, and four of which showed significant inhibitions.     

A novel approach in potential anticoagulants from peptides epitope 558–565 of A2 subunit of factor VIII

Factor VIII, a human blood plasma protein, plays an important role during the intrinsic pathway of blood coagulation cascade after its activation by thrombin. The activated form of FVIII acts as cofactor to the serine protease Factor IXa, in the conversion of the zymogen Factor X to the active enzyme Factor Xa. The Ser⁵⁵⁸–Gln⁵⁶⁵ region of the A2 subunit of Factor VIII has been shown to be crucial for FVIIIa–FIXa interaction. Based on this, a series of linear peptides, analogs of the 558–565 loop of the A2 subunit of the heavy chain of Factor VIII were synthesized using the acid labile 2-chlorotrityl chloride resin and biologically evaluated in vitro by measuring the chronic delay of activated partial thromboplastin time and the inhibition of Factor VIII activity, as potential anticoagulants.     

Enzymatic Properties of β-Xylosidase from Malbranchea pulchella var. sulfurea No. 48

Some enzymatic properties of Malbranchea β-xylosidase were investigated. The β- xylosidase activity was inhibited by Hg²⁺, Zn²⁺, Cu²⁺, N-bromosuccinimide, p-chloromercuribenzoate and sodium laurylsulfate, while this activity was activated by Ca²⁺. The enzyme released xylose as the end product even from 10% xylobiose solution without forming any xylooligosaccharides. The enzyme well acted on aryl-β-d-xylosides, but showed no activity on alkyl-β-d-xylosides, and it was practically free from glucosidase activity. The Km and V_max values of this enzyme for xylobiose were calculated to be 2.86 × 10^?8 m and 34.5 μmoles/mg/min, respectively, and these values determined for phenyl-β-d-xyloside were 3.01 × 10^?8 m and 16.2 μmoles/mg/min, respectively.     

Fluorescence studies of ATP-diphosphohydrolase from Solanum tuberosum var. Desirée

Chemical modification of potato apyrase suggests that tryptophan residues are close to the nucleotide binding site. Kd values (+/- Ca2+) for the complexes of apyrase with the non-hydrolysable phosphonate adenine nucleotide analogues, adenosine 5'-(beta,gamma-methylene) triphosphate and adenosine 5'-(alpha,beta-methylene) diphosphate, were obtained from quenching of the intrinsic enzyme fluorescence. Other fluorescent nucleotide analogues (2'(3')-O-(2,4,6-trinitrophenyl) adenosine 5'-triphosphate, 2'(3')-O-(2,4,6-trinitrophenyl) adenosine 5'-diphosphate. 1,N6-ethenoadenosine triphosphate and 1,N6-ethenoadenosine diphosphate) were hydrolysed by apyrase in the presence of Ca2+, indicating binding to the active site. The dissociation constants for the binding of these analogues were calculated from both the decrease of the protein (tryptophan) fluorescence and enhancement of the nucleotide fluorescence. Using the sensitised acceptor (nucleotide analogue) fluorescence method, energy transfer was observed between enzyme tryptophans and ethene-derivatives. These results support the view that tryptophan residues are present in the nucleotide-binding region of the protein, appropriately oriented to allow the energy transfer process to occur.     

Purification and Properties of Lytic, β-1, 3-Glucanase from Flavobacterium dormitator var. glucanolyticae

An endo β-1, 3-glucanase which is able to disrupt the cells of living yeast has been purified in homogeneous state from the culture filtrate of Flavobacterium dormitator var. glucanolyticae. The molecular weight of the enzyme was estimated to be 17,000 ~ 22,000. The mode of enzyme action has been suggested to be a “random” type of β-1, 3-glucanase. The enzyme preferes larger chains saccharides as substrate for its action, however, smaller oligosaccharides such as laminaritriose and laminaribiose are also decomposed by the enzyme. The Km values of the enzyme for laminarin, laminarihexaose, and laminaritetraose were determined to be 0.26, 1.18, and 2.00 g/liter, respectively. The ability of this enzyme to disrupt the cells of living yeast is its remarkable point, since endo β-1, 3-glucanase of a smaller oligosaccharide-producing type from most sources has been recognized to be inactive (or very weakly active) on living yeast cells.