Naturally occurring iridoids. A review, part 1.
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A compilation of new naturally occurring iridoid glycosides, iridoid aglycones, iridoid derivatives and bis-iridoids reported during 1994-2005 is provided with available physical and spectral data: mp, [alpha]D, UV, IR, 1H- and 13C-NMR as well as natural source with family and references. 418 compounds with 202 references are cited. (+info)
New constituents from the leaves of Morinda citrifolia.
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A new iridoid glycoside, citrifoside (1), and a new anthraquinone, 1,5,15-trimethylmorindol (2), together with 24 known compounds, were isolated from the leaves of Morinda citrifolia. The structures of the new compounds were elucidated by spectral data. 1,5,15-Trimethylmorindol (2) did not show significant cytotoxic activity by itself but showed cytotoxicity when combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), while citrifoside (1) did not show any activity even with TRAIL. (+info)
Coumaroyl iridoids and a depside from cranberry (Vaccinium macrocarpon).
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Cranberry (Vaccinium macrocarpon) juice has been used for urinary tract infections for approximately 50 years. Recent research suggests that this botanical blocks adherence of pathogenic E. coli to urinary tract cells, thus preventing infection. While current evidence indicates that proanthocyanidins are responsible for this activity, these compounds may not reach the urinary tract; thus further investigation is warranted. Fractionation of cranberry juice concentrate was guided by a recently published antiadherence assay, and the resulting fractions were phytochemically characterized. Two new coumaroyl iridoid glycosides, 10-p-trans- (1) and 10-p-cis-coumaroyl-1S-dihydromonotropein (2), and a depside, 2-O-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxyphenylmethylacetate (3), were isolated, and although these compounds did not have antiadherent activity in isolation, they might constitute a new group of marker compounds for this active fraction of cranberry. (+info)
Naturally occurring secoiridoids and bioactivity of naturally occurring iridoids and secoiridoids. A review, part 2.
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Naturally occurring new secoiridoids published during 1994-2005 are reviewed with available physical and spectral data: mp, [alpha](D), UV, IR, (1)H- and (13)C-NMR and plant source. The works on biological and pharmacological activity of naturally occurring iridoids and secoiridoids reported during 1998-2005 are also reviewed. Bioactivities like antiallergic, antiarthritis, antibacterial, anticancer, anticoagulant, anticomplement, antifungal, antiinflammatory, antioxidative, antiprotozoal, antispasmodic, antiviral, immunomodulatory, neuroprotective, nerve growth factor potentiating and wound healing activities are highlighted. (+info)
Identification of antidiabetic effect of iridoid glycosides and low molecular weight polyphenol fractions of Corni Fructus, a constituent of Hachimi-jio-gan, in streptozotocin-induced diabetic rats.
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In our previous study, Corni Fructus (Cornus officinalis SIEB. et ZUCC.), a component crude drug of the Chinese prescription Hachimi-jio-gan, was reported to reduce glucotoxicities, up-regulate renal function, and consequently ameliorate glycation-associated renal damage as well as Hachimi-jio-gan. Based upon these facts, we prepared Corni Fructus fractions and evaluated which fraction contained the effective components against diabetes, using one iridoid glycoside and three polyphenol fractions, which were expected to possess stronger activities than Corni Fructus, administered orally at a dose of 20 mg/kg body weight/d for 10 d, respectively. As a result, iridoid glycosides and low molecular weight polyphenol fractions could reduce the pathogenesis of diabetic renal damage, each having different mechanisms, i.e., iridoid glycosides successfully decreased the hyperglycemic state and affected renal advanced glycation end-product (AGE) accumulation, such as N(epsilon)-(carboxyethyl)lysine and N(epsilon)-(carboxymethyl)lysine, while low molecular weight polyphenol fractions could reduce renal lipid peroxidation, the receptor for AGE, and inducible nitric oxide synthase. Overall, these data suggest that iridoid glycosides and low molecular weight polyphenols purified from Corni Fructus improve metabolic parameters associated with the development of diabetic renal damage. The main active components of these fractions are discussed. (+info)
Simultaneous qualitation and quantification of thirteen bioactive compounds in Flos lonicerae by high-performance liquid chromatography with diode array detector and mass spectrometry.
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A high-performance liquid chromatography (HPLC) with diode array detector (DAD) and electrospray ionization mass spectrometry (ESI-MS) was established for the simultaneous determination of thirteen bioactive compounds in Flos Lonicerae. The optimal chromatographic conditions were obtained on a C(18) column (250x4.6 mm, 5.0 microm) with the column temperature at 30 degrees C. The mobile phase was composed of (A) acetic acid aqueous (0.4%, v/v) and (B) acetonitrile using a gradient elution, the flow rate was 1 ml/min. Detection wavelengths were set at 240 nm for iridoids (loganin, sweroside, secoxyloganin and centauroside), 330 nm for phenolic acids (chlorogenic acid, caffeic acid, 4,5-di-O-caffeoyl quinic acid and 3,4-di-O-caffeoyl quinic acid) and 360 nm for flavonoids (rutin, hyperoside, quercetin-3-O-glucoside, luteolin-7-O-glucoside and lonicerin). The identities of the peaks were accomplished by comparing retention times, UV and mass data with reference compounds under the same conditions. All calibration curves showed good linear regression (r(2)>0.9983) within test ranges. The developed method provided satisfactory precision and accuracy with overall intra-day and inter-day variations of 0.78--1.85% and 1.13--2.36%, respectively, and the overall recoveries of 91.3--104.2% for the thirteen compounds analyzed. The verified method was successfully applied to quantitative determination of the three types of bioactive compounds in ten commercial Flos Lonicerae samples from different markets in China. The analytical results demonstrated that the contents of the thirteen analytes were relatively variant. (+info)
A fibrinogen-based precision microporous scaffold for tissue engineering.
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Fibrin has been long used as an effective scaffolding material to grow a variety of cells and tissue constructs. It has been utilized mainly as a hydrogel in varying concentrations to provide an environment in which suspended cells work to rearrange the fibers and lay down their own extracellular matrix. For these fibrin hydrogels to be useful in many tissue-engineering applications, the gels must be cultured for long periods of time in order to increase their mechanical strength to the levels of native tissues. High concentrations of fibrinogen increase the mechanical strength of fibrin hydrogels, but at the same time reduce the ability of cells within the scaffold to spread and survive. We present a method to create a microporous, nanofibriliar fibrin scaffold that has controllable pore size, porosity, and microstructure for applications in tissue engineering. Fibrin has numerous advantages as a scaffolding material as it is normally used by the body as temporary scaffolding for tissue regeneration and healing, and can be autologously sourced. We present here a scaffolding process which enhances the mechanical properties of the fibrin hydrogel by forming it surrounding poly(methyl-methacrylate) beads, then removing the beads with acetone to form an interconnected microporous network. The acetone serves the dual purpose of precipitating and fixing the fibrinogen-based scaffolds as well as adding strength to the network during polymer bead removal. Effects of fibrinogen concentration and time in acetone were examined as well as polymerization with thrombin. A natural crosslinker, genipin, was also used to add strength to the scaffolds, producing a Young's modulus of up to 184+/-5 kPa after 36 h of reaction. Using these methods we were able to produce microporous fibrin scaffolds that support cell growth and have mechanical properties similar to many native tissues. (+info)
On the chemical constituents of Dipsacus asper.
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Bioassay-guided fractionation of 95% EtOH extract from the roots of Dipsacus asper lead to the isolation of some phenolic acids (caffeic acid, 2,6-dihydroxycinnamic acid, vanillic acid, 2'-O-caffeoyl-D-glucopyranoside ester, and caffeoylquinic acid) as the major active components, and five new iridoid glucoside dimers (1-5) and one new iridoid glucoside monomer (6), other known iridoid glycosides loganin, cantleyoside, triplostoside A, lisianthioside, 6'-O-beta-D-apiofuranosyl sweroside, as well as triterpenoids oleanic acid and akebiasaponin D. The structures of new compounds 1-6 were determined as dipsanosides C (1), D (2), E (3), F (4), G (5), and 3'-O-beta-D-glucopyranosyl sweroside (6) by spectroscopic, including 1D and 2D NMR techniques, and chemical methods. (+info)