Quantitative Analysis of Anti-inflammatory and Radical Scavenging Triterpenoid Esters in Evening Primrose Oil

Cold pressed, nonraffinated evening primrose oil (EPO) was recently found to contain lipophilic triterpenoidal esters with radical scavenging and anti-inflammatory properties. A simple and robust method for the quantitative analysis of these 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid was developed and validated. Separation was achieved by normal phase chromatography on a Diol column and with hexane/ethyl acetate (50:50) as eluent. The analytes could be determined directly in the oil matrix, without need of a previous removal of the triglycerides. Normal phase LC ESI-MS with a makeup flow of polar modifier was used for checking the identity and purity of analyte peaks. Samples from 22 commercially available EPOs were analyzed. The average caffeoyl ester contents were 58 mg/100 g in cold pressed oils and 4.7 mg/100 g in partially raffinated oils. In fully raffinated EPO samples, the concentration was below the limit of detection. The influence of extraction temperature on the content of caffeoyl esters in nonraffinated EPO was investigated with seeds of Oenothera biennis and Oenothera lamarckiana, respectively. With O. lamarckiana, the concentration of caffeoyl esters in the oil increased with rising pressure and temperature, whereas no such dependency was found with O. biennis. Microscopic analysis revealed some differences in the histology of the seed testa, which may explain in part the differing behaviors in the extraction experiments. There was a difference between O. biennis and O. lamarckiana oils with respect to the relative amounts of the three esters. The temperature of the extraction process had no effect on the ratio of the compounds. Keywords: Evening primrose oil; Oenothera biennis; Oenothera lamarckiana; Onagraceae; caffeoyl ester; triterpenoid; HPLC; radical scavenger; anti-inflammatory; normal-phase LC ESI-M

Occurrence of Stable Foam in the Upper Rhine River Caused by Plant-Derived Surfactants

For 30 yr, a persistent foam cover has been observed during the summer months in the Rhine River beneath the Rhine Fall, a waterfall near Schaffhausen, Switzerland. This phenomenon has been a matter of public concern ever since its first appearance, but all previous attempts to clarify the origin of this foam had remained inconclusive. With the aid of electrospray LC−MS, triterpene saponins and mono- and digalactosyldiacylglycerolipids (MGDAG and DGDAG), two classes of tensioactive metabolites occurring in the aquatic plant Ranunculus fluitans Lamk. (Ranunculaceae), were detected in river water and foam samples. Saponin concentrations in water and foam samples were monitored at regular intervals during the years 1998 and 2000. Other compound classes with surfactant properties such as proteins, humic acids, and synthetic detergents were also analyzed. Foam occurrence paralleled with saponin concentration and with the amounts of detached Ranunculus biomass accumulating at the dam of the hydroelectric power plant of Schaffhausen located just above the Rhine Fall but not with the concentration of synthetic detergents. The ecotoxicological potential of Ranunculus constituents, water, and foam samples was checked with a representative range of aquatic indicator organisms. No acute toxicity was observed at concentrations that were at least 50-fold higher than those found in the environmental samples

Quantitative Analysis of Anti-inflammatory and Radical Scavenging Triterpenoid Esters in Evening Primrose Oil

Cold pressed, nonraffinated evening primrose oil (EPO) was recently found to contain lipophilic triterpenoidal esters with radical scavenging and anti-inflammatory properties. A simple and robust method for the quantitative analysis of these 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid was developed and validated. Separation was achieved by normal phase chromatography on a Diol column and with hexane/ethyl acetate (50:50) as eluent. The analytes could be determined directly in the oil matrix, without need of a previous removal of the triglycerides. Normal phase LC ESI-MS with a makeup flow of polar modifier was used for checking the identity and purity of analyte peaks. Samples from 22 commercially available EPOs were analyzed. The average caffeoyl ester contents were 58 mg/100 g in cold pressed oils and 4.7 mg/100 g in partially raffinated oils. In fully raffinated EPO samples, the concentration was below the limit of detection. The influence of extraction temperature on the content of caffeoyl esters in nonraffinated EPO was investigated with seeds of Oenothera biennis and Oenothera lamarckiana, respectively. With O. lamarckiana, the concentration of caffeoyl esters in the oil increased with rising pressure and temperature, whereas no such dependency was found with O. biennis. Microscopic analysis revealed some differences in the histology of the seed testa, which may explain in part the differing behaviors in the extraction experiments. There was a difference between O. biennis and O. lamarckiana oils with respect to the relative amounts of the three esters. The temperature of the extraction process had no effect on the ratio of the compounds. Keywords: Evening primrose oil; Oenothera biennis; Oenothera lamarckiana; Onagraceae; caffeoyl ester; triterpenoid; HPLC; radical scavenger; anti-inflammatory; normal-phase LC ESI-M

A Simple Isolation Method for the Major Catechins in Green Tea Using High-Speed Countercurrent Chromatography

An efficient protocol for the preparative purification of the major tea catechins (−)-epicatechin gallate (3) and epigallocatechin gallate (5) has been developed, employing liquid−liquid partitioning, high-speed countercurrent chromatography, and gel chromatography for final purification. The method is suitable for scale-up to significantly larger quantities

Isolation and purification of terpenoid compounds from <i>Ferula haussknechtii</i> and evaluation of their antibacterial effects

The roots of F. haussknechtii are used by local people in order to treat wounds and urinary infections. Ferula species are rich in bioactive compounds with biological effects. In line with our previous studies about screening antibacterial natural products, five terpenoid derivatives were purified from Ferula haussknechtii. The separation and purification were performed by column chromatography. Their structures were determined by 1 D and 2 D NMR as hawraman 8-p-hydroxybenzoyl-tovarol (1), ferutinin (2), lancerotriol 6-(p-hydroxybenzoate) (3), chimganin (4), and chimgin (5). Then, the antibacterial effects of the purified compounds were evaluated by measuring their MIC values against Gram-positive and Gram-negative bacteria. The results showed that compound (1) had the most antibacterial effect on Bacillus cereus (MIC = 16 µg/mL). The antibacterial effects of F. haussknechtii compounds are in line with their local application and it is suggested that further studies should be conducted to determine their mechanism of action.</p

Total Synthesis and Neuritotrophic Activity of Farinosone C and Derivatives

An efficient synthesis of all four possible stereoisomers of the neurotrophic amide farinosone C was developed. The absolute and relative configuration was assigned by comparison of synthetic material with a derivatized authentic sample of the natural product. Several derivatives allowed for the generation of preliminary structure activity relationships concerning neurite outgrowth in PC-12 cells, unravelling l-tyrosinol-amide as the pharmacophore

Total Synthesis and Neuritotrophic Activity of Farinosone C and Derivatives

An efficient synthesis of all four possible stereoisomers of the neurotrophic amide farinosone C was developed. The absolute and relative configuration was assigned by comparison of synthetic material with a derivatized authentic sample of the natural product. Several derivatives allowed for the generation of preliminary structure activity relationships concerning neurite outgrowth in PC-12 cells, unravelling l-tyrosinol-amide as the pharmacophore

Novel Tetramic Acids and Pyridone Alkaloids, Militarinones B, C, and D, from the Insect Pathogenic Fungus <i>Paecilomyces </i><i>m</i><i>ilitaris</i>

Three yellow pigments were isolated from a mycelial extract of the entomopathogenic fungus Paecilomyces militaris. With the aid of spectroscopic means, one compound was identified as a new pyridone alkaloid, militarinone D (1). The two other metabolites were characterized as two novel 3-acyl tetramic acids, militarinones B (2) and C (3). In contrast to the structurally related pyridone militarinone A (4), compounds 1−3 showed only negliable neuritogenic activity in PC-12 cells, whereas militarinone D (1) exhibited cytotoxicity. On the basis of a co-occurrence of 3-acyl tetramic acids and biogenetically related pyridone alkaloids in P. militaris, a revised biosynthetic pathway for pyridone alkaloids is proposed

Case Study of the Swiss Flora for Prior Phytochemical and Biological Investigations

Estimates in the literature as to what extent the world’s higher plant species have been studied chemically or for bioactivity are contradictory and range from 0.5% to >12%. In this survey, a model to make credible estimates of the extent of their study is proposed and is exemplified by applying it in a case study of plants native to Switzerland. Using a widely available database (SciFinder Scholar), 454 535 literature references for the 2677 native Swiss plant species were retrieved. It was determined that 55% of these species have been investigated phytochemically and 28% for biological activity. The influence of factors such as commonness, growth form, habitat, medicinal use, and reported toxicity on the extent to which different plant groups have been studied is analyzed. The predictive value of random sampling of subsets of plants is compared to the study of the entire Swiss flora, to show that a credible estimate of the extent of prior studies can be achieved with just 5% of these species

Quantitative Analysis of Anti-inflammatory and Radical Scavenging Triterpenoid Esters in Evening Primrose Seeds

Lipophilic triterpenoidal esters with radical scavenging and cyclooxygenase inhibitory properties were recently found in cold-pressed, nonraffinated evening primrose oil (EPO). A quantitative assay for the analysis of 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid in evening primrose seeds was developed and validated. Extraction efficiency >99% was achieved by means of pressurized liquid extraction with two extraction cycles and 80% (v/v) ethanol at 120 °C. Analysis of esters was by normal-phase high-performance liquid chromatography on a Diol column and hexane/ethyl acetate (containing 0.1% formic acid) (65:35) as the eluent. The analytes were determined without further prepurification. Seeds from defined cultures of Oenothera biennis, Oenothera lamarckiana, and Oenothera ammophila, grown under identical conditions, were analyzed. The cultures originated from seeds from eight collections in the wild and from selections from five cultivars. The content of total triterpenoidal esters in seeds varied between 1.34 and 2.78 mg/g. Three types of qualitative patterns were observed for the triterpenoidal esters. The influence of different harvest times and plant treatments was studied with the cultivar Anothera. Variations between 1.5 and 2.3 mg/g were found. Keywords: Evening primrose oil; Oenothera biennis; Oenothera lamarckiana; Oenothera ammophila; Onagraceae; caffeoyl ester; triterpenoid; pressurized liquid extraction; accelerated solvent extraction; HPLC; radical scavenger; anti-inflammator