Oxidation of methylophiopogonanone A on the surface of TLC plate.

Methylophiopogonanone A (MOPNA, 1) is a characteristic homoisoflavonoid, having two methyl groups on the A ring, isolated from Ophiopogon Root (enlarged part of the root of Ophiopogon japonicus Ker-Gawler, Liliaceae). Although MOPNA is chemically stable in various organic solvents, such as acetone, chloroform, methanol and dimethyl sulfoxide, it gave a spot of higher polarity in addition to the spot of MOPNA on the surface of TLC plate. The spot was isolated and the structure of the major compound was revealed to be a compound with an oxygen atom at C-6 of the A ring. This oxidation on the surface of TLC plate was observed for synthetic intermediates of MOPNA having two methyl groups on a phloroacetophenone-type ring, suggesting that the methyl groups enhanced susceptibility to air oxidation. The structure of the major oxidation product was similar to those of humulone and sufflomin A. Humulone has two prenyl units and sufflomin A has two C-glucosyl moieties instead of the two methyl groups, respectively. As dialkylated phloroacetophenone derivatives seem susceptible to oxidation, air oxidation might be involved in the formation of these compounds.

Two new homoisoflavones from Portulaca oleracea L. and their activities.

Two new compounds, identified as 3-(2-hydroxybenzyl)-6,8-dimethoxy-4H-chromen-4-one (1), named oleracone J and 3-(2-hydroxybenzyl)-6,8-dimethoxychroman-4-one (2), named oleracone K, were isolated from Portulaca oleracea L., and the structures of them were determined by spectroscopy, including one-dimensional and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionisation time-of-flight mass spectrometry. The two compounds have scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 values of 18.34, 23.92 µM, and anticholinesterase activities with IC50 values of 59.08, 67.89 µM, respectively.

Synthesis of heterocyclic analogs of isoflavone and homoisoflavone based on 3-formylchromone.

The review is focused on recent developments of chemistry of synthetic analogs of natural compounds, isoflavone and homoisoflavone. The possible synthetic strategies to access heterocyclic analogs of these compounds starting from readily available 3-formylchromone and its derivatives (3-cyanochromone, 2-amino-3-formylchromone) and products of its condensation with simplest C- and N-nucleophiles are discussed. The structural features of the reaction products that depend on the nature of the reaction medium, structure of the starting compounds, and reagent ratio are considered. Particular attention is given to the application of the modern strategies of organic synthesis, namely green chemistry approaches, click reactions, domino reactions, etc. Examples of compounds of this group most promising for clinical application due to wide and pronounced pharmacological effects are given.

Effect of food processing on the antioxidant activity of flavones from Polygonatum odoratum (Mill.) Druce.

Polygonatum odoratum (Mill.) Druce (POD) is a natural plant widely used for food and medicine, thanks to its rich content of a strong antioxidant agent called homoisoflavones. However, food processing methods could affect the stability of POD flavones, resulting in changes to their antioxidant activity. This study attempts to evaluate the antioxidant activity of POD flavones subject to different processing methods and determines which method could preserve the antioxidant activity of POD flavones. Therefore, flavones were extracted from POD samples, which had been treated separately with one of the four processing methods: extrusion, baking, high-pressure treatment, and yeast fermentation. After that, the antioxidant activity of the flavones was subject to in vivo tests in zebrafish embryos. The results show that yeast fermentation had the least disruption to the antioxidant activity of POD flavones, making it the most suitable food processing method for POD. By contrast, extrusion and high-pressure treatment both slightly weakened the antioxidant activity of the flavones and should be avoided in food processing. The research results provide a reference for the development and utilization of POD and the protection of its biological activity.

Polygonatone H, a new homoisoflavanone with cytotoxicity from Polygonatum Cyrtonema Hua.

A new homoisoflavonoid, (3R)-5,7-dihydroxy-6-methyl-3-(2'-hydroxy-4'-methoxybenzyl)-chroman-4-one (1), namely polygonatone H, in addition to fourteen known homoisoflavones (2-15) were isolated from the rhizome of Polygonatum Cyrtonema Hua. The structures were identified with the aid of 1D/2D NMR spectroscopic technologies. Compounds 2, 6, 8, 10, 11, 13, and 15 were isolated from P. Cyrtonema for the first time. Compound 1 showed cytotoxicities to human cancer cell lines with IC50 values to comparable those of cisplatin.

A new homoisoflavone from Portulaca oleracea L. and its antioxidant activity.

A new compound was identified as 3-(2-hydroxybenzyl)-5,7-dimethoxy-4H-chromen-4-one (or 2'-dihydroxy-5,7-dimethoxy-homoisoflavone), oleracone F (1), together with p-hydroxy ethyl cinnamate (2) and 4-hydroxy-3-methoxy ethyl cinnamate (3) isolated from the Portulaca oleracea L. for the first time and six known compounds, salicylic acid (4), ß-carboline-3-carboxylic acid (5), aurantiamide (6), portulacanone A (7), B (8) and C (9). Their structures were determined using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance and high-resolution electrospray ionization time-of-flight mass spectrometry. Notably, oleracone F (1) presented scavenging activity in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 value of 17.78 µM.

Anti-inflammatory activities of Ophiopogonis Radix on hydrogen peroxide-induced cellular senescence of normal human dermal fibroblasts.

Ophiopogonis Radix (Ophiopogon root), which nourishes the yin, has been used in clinical practice to promote fluid secretion and to moisturize the lungs and skin in traditional Chinese and Japanese (Kampo) medicine. To evaluate this traditional medicinal effect, we investigated the anti-chronic inflammatory effect of Radix Ophiopogonis on senescent cells. Conversely, although several phenotypes of Ophiopogon japonicus Ker-Gawler (Liliaceae) are prevalent in Japan and China, we used these Ophiopogon roots by considering them as one crude drug, Ophiopogonis Radix. In this study, it was revealed that there are two chemotypes (Types A and B) in the root of the original plant, O. japonicus. Methylophiopogonanone A (compound 1) and methylophiopogonanone B (compound 2) were isolated as index compounds from Type A and compound 1 and ophiopogonanone A (compound 3) from Type B. In addition, ophiopogonin B (compound 4) was isolated as the main steroidal saponin from both Type A and B. The results indicated that two different methanol extracts (from Types A and B) and the main constituents of O. japonicus (compound 1-4), significantly downregulated the expression of interleukin (IL)-6 and IL-8, which were enhanced by senescent normal human dermal fibroblasts. Moreover, the two different methanol extracts and compounds 1-4 decreased IL-6 production in a strong and concentration-dependent manner by the ELISA method.

Comparison on homoisoflavones extracted from Ophiopogon japonicus in Sichuan and Zhejiang and their anti-oxidative activity / 中草药

Objective: To compare the contents of three homoisoflavones and their anti-oxidative activity of Ophiopogon japonicus in Sichuan (OJS) and Zhejiang (OJZ). Methods: The determination was performed on ACQUITYTM UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm), the Ultra Performance Liquid Chromatography-Photo-Diode Array (UPLC-PDA) technology was applied, and the mobile phase consisted of acetonitrile and 0.2% formic acid aqueous solution (55:45) with gradient elution program, flow rate was 0.20 mL/min with 2 μL of sample quantity at 296 nm, and the anti-DPPH radical efficiency of water extract from Ophiopogonis Radix were evaluated by UV-photometer. Results: The average values of methylophiopogonone A, methylophiopogonanone A, and methylophiopogonanone B were (3.06±0.54), (40.10±5.63), and (29.51±5.06) μg/g in OJS, respectively; while those in OJZ were (9.22±3.52), (106.63±27.56), and (256.97±61.79) μg/g, separately. The IC50 value was 16.59 mg/mL in OJS, while that in OJZ was 14.48 mg/mL. The IC50 value of positive control VC was 7.06 μg/mL. Conclution: Compared with OJS, the contents of homoisoflavones in OJZ are higher, and the anti-radical efficiency of water extract from OJZ is stronger. It provides the basis for the quality evaluation and geo-authentic research of Ophiopogonis Radix.

Study on homoisoflavones in Shengmai injection / 中国药学杂志

OBJECTIVE: To investigate the composition of homoisoflavones in Shengmai injection. METHODS: On the basis of studies on the chemical constituents of Ophiopogonis Radix extract, the chemical constituents in Shengmai injection from eight enterprises were identified by LC-MS. RESULTS: Ophiopogonone B, ophiopogonanone B, ophiopogonanone A, methylophiopogonanone A, and methylophiopogonanone B were the common components among the eight identified constituents in Ophiopogonis Radix extract. CONCLUSION: The analytical method for homoisoflavones in Shengmai injection is established, which can be used as the basis for further study and quality control. Copyright 2012 by the Chinese Pharmaceutical Association.

On-line determination of scavenging effect of Ophiopogon japonicus for superoxide anion radicals by HPLC-DAD coupled with chemiluminescence / 中国药科大学学报

The scavenging activities of Ophiopogon japonicus for superoxide anion (O_2~(·-)) radicals by HPLC-DAD coupled with chemiluminescence(CL) was studied and the active constituents in it were screened.The aqueous extracts of Ophiopogon japonicus were divided into the ethyl ether fraction and the n-butanol fraction.Their activities were investigated respectively and the reduction of CL with the pyrogallic acid 3-amino-phthalhydrazid (luminol) Na_2CO_3/NaHCO_3 buffer (pH 11.0) system worked as an activity index of the antioxidant constituents.Major active components in Ophiopogon japonicus could be identified by HPLC-DAD-MS/MS and the reference substances.The antioxidant activities of different ingredients were evaluated by standard potency equations using quercetin as positive control.The experimental data indicated that the scavenging activities of Ophiopogon japonicus for superoxide anion (O_2~(·-)) radicals are mainly from homoisoflavone in the ethyl ether fraction.It has shown that the method for on-line detection is an advantageous tool to rapidly determinate antioxidants from complex herbs.