Mixture Of Aglycones Research Articles

A Comparative Analysis of the Photo-Protective Effects of Soy Isoflavones in Their Aglycone and Glucoside Forms

Isoflavones exist in nature predominantly as glucosides such as daidzin or genistin and are rarely found in their corresponding aglycone forms daidzein and genistein. The metabolism and absorption of isoflavones ingested with food is well documented, but little is known about their use as topical photo-protective agents. The aim of this study was to investigate in a comparative analysis the photo-protective effects of isoflavones in both their aglycone and glucoside forms. In human skin fibroblasts irradiated with 60 mJ/cm2 ultraviolet B (UVB), we measured the expression levels of COX-2 and Gadd45, which are involved in inflammation and DNA repair, respectively. We also determined the cellular response to UVB-induced DNA damage using the comet assay. Our findings suggest that both the isoflavone glucosides at a specific concentration and combination with an aglycone mixture exerted an anti-inflammatory and photo-protective effect that prevented 41% and 71% of UVB-induced DNA damage, respectively. The advantages of using either isoflavone glucosides or an aglycone mixture in applications in the field of dermatology will depend on their properties and their different potential uses.

In vitro and in vivo evaluation of topical delivery and potential dermal use of soy isoflavones genistein and daidzein

Genistein, daidzein, and glycitein are soy isoflavones. These compounds can be used to protect the skin from oxidative stress induced by UVB radiation. To this end, the feasibility of skin absorption of soy isoflavones was evaluated in the present study. As assayed by flow cytometry, UVB-induced H 2O 2 production in keratinocytes was inhibited by genistein and daidzein, confirming that these two compounds can act as free radical scavengers when keratinocytes are photodamaged. Glycitein showed no protective activity against photodamage. The effects of vehicles on the in vitro topical delivery from saturated solutions such as aqueous buffers and soybean oil were investigated. The isoflavones in a non-ionized form (pH 6) showed higher skin deposition compared to the ionized form (pH 10.8). Soybean oil reduced the isoflavone amount retained in the skin, especially for genistein. Genistein generally exhibited greater skin absorption than did daidzein. However, daidzein permeation was enhanced when an aglycone mixture was used as the active ingredient. An eutectic effect was proposed as the enhancing mechanism. In vivo skin deposition showed a linear correlation with the in vitro results. The safety profiles suggested no or only negligible stratum corneum disruption and skin erythema by topical application of soy isoflavones. It was concluded that topical delivery may serve as a potent route for soy isoflavones against photoaging and photodamage.

Determination of flavonoids in cultivated sugarcane leaves, bagasse, juice and in transgenic sugarcane by liquid chromatography-UV detection

A high-performance liquid chromatography (HPLC) method with photo-diode array (DAD) detection was developed to separate and quantify flavonoids in sugarcane leaves and bagasse (= the crushed sugarcane refuse from juice extraction), and in sugarcane juice. Sugarcane flavonoids consist of a complex mixture of aglycones and glycosides (including flavonolignan glycosides), and the HPLC-UV method herein proposed is suitable for their quantification as total flavonoids. This method was applied to analyze samples of cultivated sugarcane, commercial juice and transgenic sugarcane leaves. Sugarcane leaves proved a promising source of flavonoids: an average of 1.10 mg of total flavonoids/g plant material was found in fresh leaves. Moreover, the flavonoid content of sugarcane juice (0.6 mg/mL) is comparable to other food sources of flavonoids previously reported. Transgenic sugarcane leaves (“Bowman-Birk” and “Kunitz”) were compared with non-modified (“control”) plant samples using the proposed HPLC-UV method, which indicated that the content of total flavonoids in transgenic plants is different from that in non-modified sugarcane.

Isoflavones Daidzein and Genistein: Preparation by Acid Hydrolysis of Their Glycosides and the Effect on Phospholipid Peroxidation

A mixture of isoflavones was obtained by acid hydrolysis of isoflavone glycosides isolated from the products of soybean processing by successive extraction with aqueous acetone and methanol. The homogeneous isoflavones daidzein and genistein were isolated from the aglycone mixture by adsorption chromatography and identified by spectral and chromatographic methods. The effect of both isoflavones on lipid peroxidation of soy phospholipids in multilamellar vesicles was studied at various concentrations. These aglycones were found to inhibit the formation of lipid hydroperoxides and malonic dialdehyde at concentrations as low as 1 mM.

Synthesis of 3β,6α-dihydroxy-5α-cholan-23-one

Evidence for the presence of 3β,6α-dihydroxy-5α-chol-9(11)-en-23-one in the aglycone mixture from the starfish Marthasterias glacialis is provided by the synthesis of 3β,6α-dihydroxy-5α-cholan-23-one ( 19 ) and its identification in the hydrogenated aglycone mixture. The side-chain is constructed from the 23,24-dinorcholanol ( 13 ) by reaction of the 22-tosylate ( 16 ) with the acetylide anion, followed by hydration of the resulting 23-yne ( 17 ).

The Glycosidically Bound Volatile Compounds ofPicea mariana(Mill.) B.S.P.

ABSTRACT The glycosidically bound volatile compounds of the black spruce, Picea mariana, from the Saguenay region of Quebec, were analyzed using both Kovats indices and GC/MS. We identified 30 compounds including the phenol 4-hydroxy-3-methoxyacetophenone as the major component (27%) followed by the terpenol linalool (20%). The relative amount of the components varies depending on the hydrolyzing enzyme. Monoterpene alcohols are an important part of the aglycone mixture in the black spruce as compared to other Coniferae species.

Variation in the flavonoid aglycone mixture excreted on the leaves of black alder ( Alnus glutinosa), from 12 different geographical origins

Black elders from 12 origins, growing at La Cantée plantation (Sologne, France), have been surveyed for the composition of the flavonoid mixture excreted on their leaves. They originate from natural sites located in Poland, Germany and France representing a N.E./S.W. transect across the natural range of Alnus glutinosa. The qualitative and quantitative distribution of 18 flavonoid aglycones among the specimens was analysed by Principal Component Analysis (PCA). This calculation applied to data recorded in a first sampling composed of 10 individuals from each of 12 geographical origins. A second matrix was prepared using 90 individuals from three provenances only, selected according to their different biomass productivity. Specimens in both samplings display an important heterogeneity in their flavonoid profiles, but no general relationship appears between the flavonoid content of specimens and their geographical origin. Likewise, there was no relationship between the expression of the flavonoid metabolism of Alnus trees and their ability in biomass production. However, using flavonoid patterns analysis remains helpful for individual characterization of Alnus glutinosa.

The distribution of asterosaponins in various body components of the starfish Leptasterias polaris

Abstract 1. 1. Asterosaponins were isolated from the aboral body wall, oral body wall, stomach, and pyloric caecum of the starfish Leptasterias polaris . 2. 2. Low-pressure liquid chromatography in conjunction with thin layer chromatography were used to delineate the mixture of saponins. 3. 3. Reverse phase high performance liquid chromatography demonstrated the presence of distinctive mixtures of saponins in the different body components, although similarities were evident in the saponin mixtures from the aboral and oral body walls, and those from the stomach and gonad. 4. 4. The saponin content was determined for each of the body components. The quantity of the saponin in the stomach was significantly higher than in the other tissues which in turn were not significant different from each other. 5. 5. The sugar content and composition was determined for each saponin mixture. Quinovose was the main sugar in all body components except the pyloric caecum where xylose predominated. 6. 6. Asterone and iso-asterone were identified from the mixture of aglycones obtained by acid hydrolysis of the saponin mixture from whole specimens.

Glycosides of marine invertebrates. VIII. Steroid glycosides of the holothurianIsostichopus badionotus

The steroid glycoside fraction ofIsostichopus badionotus, consisting of a mixture of D-xylosides of steroid alcohols, has been isolated by column chromatography on silica gel. The mixture of aglycones obtained after acid hydrolysis was separated with the aid of argentation chromatography into several fractions. GLC-MS analysis, and also the use of IR and13C NMR spectroscopy has shown that the steroid glycosides ofI. badionotus are xylosides of Δ0-, Δ7-, Δ22-, and Δ7.22-, C27-, C28-, and C29-steroids of the cholestane series.

High-pressure liquid chromatography of steroidal alkaloids

High-pressure liquid chromatography was used to separate the following steroidal alkaloids: tomatidine, solanidine, solasodine, rubijervine, veratramine and jervine. The method was used to prepare crystalline solanidine from a crude mixture of aglycones obtained from Solanum chacoense, and to separate radioactive solanidine from extracts of potato plants fed with [4- 14C]cholesterol.

3-Epistrophanthidin and 3-epistrophanthidol

The hydrolysis of the total glycosides of the seeds ofStrophanthus kombe Oliv. and the adsorption-chromatographic separation of the mixture of aglycones has given strophanthidin, strophanthidol, 17β-H-strophanthidin, and two new cardenolides denoted by the symbols IM-38 and IM-40 in the individual state. On the basis of the investigations carried out, the new cardenolides have been characterized provisionally as 3-epistrophanthidin and 3-epistrophanthidol.

The pregnane glycosides of the climbing form of Sarcostemma viminale (L.) R

AbstractThe dried twigs and stems of Sarcostemma viminale (the climbing shrub form from South Rhodesia) contain about 1% phenolic and a similar amount of glycosidic compounds derived from 2‐deoxysugars; only traces of cardenolides are present. After mild acidic hydrolysis 5 sugars could be detected and subsequently isolated in pure form. Three of them (d‐cymarose, d‐digitoxose and lilacinobiose) were obtained crystalline, the two others (d‐oleandrose and viminose) in amorphous form. Viminose is a new sugar, a disaccharide which contains d‐thevetose, and d‐Digitoxose at the reducing end [30 b].The mixture of aglycones, obtained after mild acidic hydrolysis, contained mainly five components (F, G, H. J and K), all of which could be isolated in pure form. F, G and J were crystalline. F was identified as metaplexigenin (1), J as mono‐O‐acetyl‐mono‐O‐benzoyl‐sarcostin (5) and K as 12,20‐di‐O‐benzoyl‐sarcostin (6). G and H are new compounds whose structures (G = 12‐O‐benzoyl‐deacetyl‐metaplexigenin (2), H = di‐O‐benzoyl‐viminolone (3)) are deduced in the following paper. After alkaline hydrolysis of the aglycone mixture, sarcostin, deacetylmetaplexigenin and small amounts of lineolon could be dedected by paper‐ and thinlayerchromatography.The two pregnane derivatives EA‐42 and EA‐43 described by Abisch et al. [21] could be identified with 3, 20‐di‐O‐benzoyl‐utendin and 3, 20‐di‐O‐benzoyl‐sarcostin, respectively.In the NMR.‐spectra of sarcostin and of many (not all) of its derivatives a strong signal (mostly a singlet corresponding to ca. 3 protons at ca. δ = 2 ppm) is present, which cannot be explained with the suggested structures. The cause of this extra signal could not be elucidated.

Macromolecular compounds isolated from airborne particles by electrophoresis and paper chromatography.

Abstract Paper chromatography and electrophoresis are used to isolate microquantities of two biologically significant compounds, “A” and “B,” from samples of airborne particles. Electrophoretic and chromatographic patterns are presented and discussed. A new rapid electrophoresis method is described which requires only two hours for separating a complicated mixture of aglycones.