HPTLC-profiling of eleutherosides, mechanism of antioxidative action of eleutheroside E1, the PAMPA test with LC/MS detection and the structure-activity relationship.

Human body is constantly generating free radicals, which causes oxidative stress. Despite naturally occurring antioxidant systems in human body, free radicals cause lipid, proteins and DNA oxidation. New antioxidants are still urgent as well as their mechanisms of action should be explained. In this study, we investigated the mechanism by which eleutherosides B, E and E1 may act as antioxidants, identified eleutherosides in Eleutherococcus lasiogyne and Eleutherococcus giraldii, and explained in vitro the absorption of eleutheroside E1 based on passive transport. The DPPH∗ and DB-HPTLC tests were used to assess the antioxidant activity. Of the three eleutherosides, only eleutheroside E1 exhibited a strong anti-DPPH∗ activity (EC50 37.03 µg/mL; 63 mMol) compared to the raw extracts (EC50 170 and 180 µg/mL for E. lasiogyne and E. giraldii). This activity was also confirmed by the DB-HPTLC autography technique. According to Zaluski's hypothesis, the antioxidant mechanism of eleutheroside E1 is based on the complexation of DPPH∗ molecule with its aryl radical. During this reaction, the aryl radical of eleutheroside E1 (E1∗) and DPPHH are created. Next, the aryl radical (E1∗) is complexed with another DPPH∗ molecule. Additionally, the aryl radical can be stabilized by the presence of the methoxy groups in the aromatic ring, which increases its antioxidative action. The HPTLC-identification of extracts showed the presence of eleutherosides B, E and E1 in both species. The PAMPA test coupled with LC/MS detection showed a low permeability of eleutheroside E1 across artificial membrane. Because eleutherosides belong to the polyphenols, the TPC and TFC were quantified. The TPC and TFC varied from 51.4 to 49.3 mg/g dry extract for TPC, and from 5.73 to 4.91 mg/g dry extract for TFC, for E. giraldii and E. lasiogyne, respectively. In conclusion, eleutheroside E1 in its pure form could be a chemopreventive ingredient of new pharmacological or dietary products, stimulating the GALT. These findings can explain partially the adaptogenic activity of eleutheroside E1 on the GALT, which has been still unknown.

In vitro anti-denaturation and anti-hyaluronidase activities of extracts and galactolipids from leaves of Impatiens parviflora DC.

The in vitro anti-denaturation and anti-hyaluronidase activities of Impatiens parviflora extracts and isolated galactolipids (MGDG-1, DGDG-1) were investigated. This is the first report on these compounds in I. parviflora. All extracts showed anti-hyaluronidase activity, but only methanolic extract from fresh leaves exhibited significant activity against heat-induced denaturation of BSA in a dose-dependent manner. At 500 µg/mL, the extract and the reference drug showed 79.05% and 99.81% inhibition of protein denaturation, respectively. These results indicate that fresh leaves of I. parviflora may be beneficial in inflammatory conditions, especially those associated with protein denaturation, such as rheumatoid arthritis. The study revealed that only MGDG-1 showed weak activity in anti-denaturation assay but both galactolipids were potent inhibitors of hyaluronidase. MGDG-1 completely inhibited the enzyme activity at the concentration of 127.9 µg/mL. These results indicate the potential of galactolipids in the treatment of diseases associated with the loss of hyaluronic acid.

Multidirectional effects of triterpene saponins on cancer cells - mini-review of in vitro studies.

Triterpene saponins (saponosides) are found in a variety of higher plants and display a wide range of pharmacological activities, including expectorant, anti-inflamatory, vasoprotective, gastroprotective and antimicrobial properties. Recently, a potential anticancer activity of saponins has been suggested by their cytotoxic, cytostatic, pro-apoptotic and anti-invasive effects. At high concentrations (more than 100 µM) saponins exert cytotoxic and haemolytic effects via permeabilization of the cell membranes. Noteworthy, the inhibition of cancer cell proliferation, the induction of apoptosis and attenuation of cell invasiveness is observed in the presence of low saponin concentrations. Saponins might affect the expression of genes associated with malignancy. These alterations are directly related to the invasive phenotype of cancer cells and depend on "cellular context". It illustrates the relationships between the action of saponins, and the momentary genomic/proteomic status of cancer cells. Here, we discuss the hallmarks of anti-cancer activity of saponins with the particular emphasis on anti-invasive effect of diverse groups of saponins that have been investigated in relation to tumor therapy.

Variation in phytochemicals and bioactivity of the fruits of Eleutherococcus species cultivated in Poland.

Neither the chemical profile and bioactivity of the fruits of Eleutherococcus species cultivated in Poland nor the influence of long-term domestic storage of the fruits are known. No changes in the phenols and flavonoids content in the freshly dried and 1-year storage fruits of Eleutherococcus senticosus and Eleutherococcus henryi were found. The 1-year storage fruits of both species exhibited a very high concentration of Mn, Zn and Cu (mg/kg) compared with the fresh-dried fruits. Spathulenol, ß-longipinene and iso-longifolol were predominant essential oil compounds. It was observed that a high capacity of the freshly dried E. senticosus fruits were able to scavenge DPPH* and inhibit Hyal (EC50 0.1 mg/mL; IC50 0.58 mg/mL). Due to their health and pharmacological benefits, a better understanding of the impact of the climate change is important to increase the pharmacological utility of the extracts.

A new cytotoxic triterpene saponin from Lysimachia nummularia L.

A new glycosylated triterpene 1 (named nummularoside) was isolated from the underground parts of Lysimachia nummularia L. Its chemical structure was elucidated as 3-O-ß-{{[ß-D-xylopyranosyl-(1→2)]-[ß-D-xylopyranosyl-(1→4)]-ß-D-glucopyranosyl-(1→4)}-[ß-D-glucopyranosyl-(1→2)-]-α-L-arabinopyranosyl]}, protoprimulagenin A on the basis of extensive NMR and MS spectral data. The saponin showed significant activity against prostate cancer cells DU145 and PC3 (EC50 1.2 and 7.4 µg/mL, respectively), while it did not affect normal cells (EC50 30 µg/mL), in contrast to the reference compound (mitoxanthrone, EC50 0.45 µg/mL). Glioblastoma cells were also significantly affected by the tested saponin (EC50 6.0 µg/mL), whereas the activity against melanoma cells was moderate (EC50 17.5-23.2 µg/mL).

Synthesis of betulin derivatives and the determination of their relative lipophilicities using reversed-phase thin-layer chromatography.

A series of superlipophilic or highly lipophilic semisynthetic betulin derivatives was prepared and their relative lipophilicity was measured by reversed-phase thin-layer chromatography (RP-TLC) at different pH values using 1,4-dioxane-acetate buffer mixtures as mobile phases. Cholesterol, 17beta-estradiol and pure betulin were used as the reference compounds. Linear relationships were found between R(M) values and 1,4-dioxane concentrations in the mobile phases. LogP values were also calculated with computer programs ACD/LogP (ChemSketch 11.0, Advanced Chemistry Development Inc.) and ClogP (Daylight Chemical Information Systems Inc.). The empirical and theoretical data were compared, and the R(M0) values correlated well with logP. Two of the synthesized betulin derivatives are reported for the first time.

A triterpene saponin from Lysimachia thyrsiflora L.

A triterpene saponoside (LTS-4) isolated from the underground parts of Lysimachia thyrsiflora L. was defined as 3-O-{beta-D-xylopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 4)-[beta-D-glucopyranosyl-(1 --> 2)]-alpha-L-arabinopyranosyl}-cyclamiretin A. Structure assignment was performed on the basis of spectroscopic data including homo- and heteronuclear 1D and 2D NMR (COSY, TOCSY, NOESY, HETCOR, HMBC and DEPT) and FAB-MS studies. The compound was tested in vitro for antimicrobial and cytotoxic activity.

Steroidal glycosides from the underground parts of Allium ursinum L. and their cytostatic and antimicrobial activity.

The aim of this study was the isolation and structural elucidation of steroidal glycosides from the underground parts of ramson Allium ursinum L. The structures of the isolated compounds were established based upon chromatographic methods and 1D- and 2D-NMR, MS and IR analyses. The mixture of two steroidal saponins: (25R)-spirost-5-en-3b-ol tetrasaccharide and (25R)-spirost-5, 25(27)-dien-3b-ol tetrasaccharide, along with a 3-hydroxypregna-5,16-dien-20-one glycoside were identified. The results of in vitro cytotoxic activity of the mixture of spirostanol saponins against cell lines melanoma B16 and sarcoma XC and human fibroblasts HSF are also reported. The spirostanol saponins mixture was investigated to determine its in vitro antimicrobal activity against Trichophyton mentagrophytes and Microsporum canis.

Cytotoxic activity of embelin from Lysimachia punctata.

A major benzoquinone pigment, embelin (1), was isolated from the underground parts of Lysimachia punctata. Compound 1 showed a significant cytotoxic activity in vitro against B16 and XC cell lines with ED50 values of 13 microg/ml and 8 microg/ml, respectively.