Adam Matkowski

Mangiferin - a bioactive xanthonoid, not only from mango and not just antioxidant.

Mangiferin is a plant natural polyphenol of C-glycosylxanthone structure and various pharmacological activities. It can be found in many plant species, among which the mango tree (Mangifera indica) is one of the primary sources. Mangiferin is also present in some medicinal herbs, influencing their therapeutic and preventive properties, and in honeybush (Cyclopia sp.), a popular South African herbal tea. Mangiferin dissolves well in water, so it can be easily extracted into infusions and decoctions. In the mangiferin molecule, four aromatic hydroxyl groups determine its strong antiradical and antioxidant properties. Mangiferin is also an efficient iron chelator, therefore preventing the generation of hydroxyl radical in Fenton-type reactions. Numerous published in vitro and in vivo pharmacological studies, demonstrated many other activities of mangiferin: analgesic, antidiabetic, antisclerotic, atimicrobial and antiviral, cardio-, hepato-, and neuroprotective, antiinflammatory, antiallergic, MAO inhibiting and memory improving, as well as radioprotective against X-ray, gamma, and UV radiation. Several studies indicated also its ability to inhibit cancerogenesis and cancer cells growth by apoptosis induction in vitro and in vivo. It is also used in cosmetics, due to antioxidant and UV-protecting properties.

Antioxidant activity of extracts from leaves and roots of Salvia miltiorrhiza Bunge, S. przewalskii Maxim., and S. verticillata L.

Three Salvia species have been studied for antioxidant activity in methanol extracts from roots and leaves. The presence of the polyphenols and tanshinones was screened by HPLC and spectrophotometric assays and related to the antioxidant potential. The antioxidant capacity of the studied species is high, but differences between species and organs have been also revealed. Salvia przewalskii leaf extract was the strongest one in all tests, followed by Salvia miltiorrhiza root and Salvia verticillata leaf. Among the roots, the most active was S. miltiorrhiza extract, followed by S. verticillata. The antioxidant activity correlates to the total polyphenol and, depending on the assay, to the hydroxycinnamic acids content. The high content of tanshinones in both S. miltiorrhiza and S. przewalskii roots is unlikely to contribute to the antioxidant activity.

Phytochemistry and bioactivity of aromatic and medicinal plants from the genus Agastache (Lamiaceae)

Agastache is a small genus of Lamiaceae, comprising 22 species of perennial aromatic medicinal herbs. In this article, we review recent advances in phytochemical, pharmacological, biotechnological and molecular research on Agastache. The phytochemical profile of all Agastache species studied to date is generally similar, consisted of two main metabolic classes—phenylpropanoids and terpenoids. In the relatively variable essential oils, most populations of different Agastache species contain over 50xa0% of a phenylallyl compound—estragole. Also, other volatile compounds (methyleugenol, pulegone, menthone, isomenthone and spathulenol) were reported in various proportions. Major non-volatile metabolites belong to phenolic compounds, such as caffeic acid derivatives, especially rosmarinic acid as well as several flavones and flavone glycosides like acacetin, tilianin, agastachoside, and a rare dimeric malonyl flavone (agastachin). Two unique lignans—agastenol and agastinol—were also isolated. Terpenoids include triterpenoids of oleanane-type (maslinic acid, oleanolic acid and β-amyrin), ursane-type (ursolic acid, corosolic acid and α-amyrin), and typical plant sterols, as well as abietane-type oxidized diterpenes (e.g., agastaquinone, agastol, and others). The bioactivity of various extracts or individual compounds in vitro and in vivo include antimicrobial, antiviral and anti-mutagenic activity, cytotoxic activity to cancer cell lines, and anti-nociceptive, anti-inflammatory, anti-atherogenic, antioxidant as well as biocidal activity to several foodstuff pests. Biotechnological and molecular studies have focused on in vitro propagation and enhancing the biosynthesis of bioactive metabolites in cell or organ cultures, as well as on the expression of genes involved in phenolic biosynthesis.

Antiplasmodial and antitrypanosomal activity of tanshinone-type diterpenoids from Salvia miltiorrhiza.

In a medium throughput screen of 880 plant and fungal extracts for antiprotozoal activity, a dichloromethane extract of Salvia miltiorrhiza roots was active against both Trypanosoma brucei rhodesiense and Plasmodium falciparum. With HPLC-based activity profiling in combination with on- and off-line spectroscopic methods (PDA, -MS (n), HR-MS, microprobe NMR), the active compounds were identified as tanshinone-type diterpenoids. Subsequent isolation and structure elucidation yielded the known substances miltirone (1), tanshinone IIu200aa (2), 1,2 dihydrotanshinquinone (3), methylenetanshinquinone (4), 1-oxomiltirone (5), 11-hydroxymiltiodiol (6), tanshinone I (7), methyltanshinonate (8), and cryptotanshinone (9). The IC₅₀s of the compounds were determined against the two parasites and rat myoblast (L6) cells. They ranged from 4.1u2009µM to over 30u2009µM against P. falciparum K1 strain with selectivity indices (SI) from 0.3 to 1.9. IC₅₀s against T. brucei rhodesiense STIB 900 were from 0.5u2009µM (1,u200a4) to over 30u2009µM, and 4 showed the greatest selective activity with an SI of 24.

Antimutagenic and anti-oxidant activities of isoflavonoids from Belamcanda chinensis (L.) DC.

The isoflavonoid fractions obtained from a methanolic extract of Belamcanda chinensis (L.) DC (syn. Iris domestica Goldblatt & Mabb.) rhizomes inhibited the chemically induced mutations in Salmonella typhimurium TA98 and TA100 in the Ames test. We have studied direct mutagenesis induced by N-nitroquinoline, and indirect mutation induction caused by metabolically activated 2-AF. The fractions enriched in isoflavonoids, obtained by sequential liquid-liquid extraction with diethyl ether and butanol, followed by ODS column separation, inhibited indirect mutagenesis in TA98 almost completely. In TA100 the maximum inhibition ranged between 80% and 100% depending on the test fraction. The inhibition of direct mutagenesis was lower, reaching about 50% in TA98 and in TA100, but it was dose-dependent only in the latter strain. Three in vitro anti-oxidant spectrophotometric assays-DPPH free-radical scavenging test, the phosphomolybdenum assay, and the linoleic acid peroxidation assay were also performed to support the process of bioactivity-guided fractionation and to provide more information about the potential mechanisms of action of the herb under study. The isoflavonoid fractions have the capability to scavenge free radicals, to reduce transition-metal ions and to protect polyunsaturated fatty acids from peroxidation. The analysis of the fractions obtained with high-performance liquid chromatography with photodiode-array and mass-spectrometric detection revealed several potentially bioactive isoflavones, either as glycosides or aglycones, depending on the polarity of the solvents used for fractionation. The main compounds were tectoridin and iridin in the glycoside fractions and the aglycones irigenin, tectorigenin, and 5,6,7,3-tetrahydroxy-4-methoxyisoflavone. The activities reported here can be regarded to be of additional value when using this plant as a phyto-estrogenic and chemopreventive agent.

Antiradical and antioxidant activity of flavones from Scutellariae baicalensis radix

We evaluated the antioxidant properties of four main flavones from Scutellaria baicalensis: baicalein, wogonin and their glucuronides – baicalin and wogonoside. We used three in vitro assays: free radical scavenging with 2,2′-diphenylpicrylhydrazyl radical, transition metal ions reducing power by phosphomolybdenum assay and inhibition of the hydroxyl radical-induced peroxidation of linoleic acid assay. All flavones have antioxidant capacity, which differs depending on the structure and mechanisms of activity. In all tests, only baicalein – the aglycone with three adjacent hydroxyl groups – exhibited consistent antioxidant effect. Wogonin protected linoleic acid against oxidation. Baicalin displayed less potent antioxidant properties whereas wogonoside did not have significant antioxidant activity.

Influence of plant growth regulators on volatiles produced by in vitro grown shoots of Agastache rugosa (Fischer & C.A.Meyer) O. Kuntze

The composition of volatile organic compounds emitted by in vitro shoots of Agastache rugosa (Fischer & C.A. Meyer) O. Kuntze (Lamiaceae) was studied using headspace solid-phase microextraction–gas chromatography–mass spectrometry and compared to the those emitted by adult plants and in vitro-germinated seedlings. Shoot-tip explants were cultured on a solid MS medium supplemented with either 4.4xa0μM 6-benzyladenine (BA), 9.3xa0μM kinetin, or 0.45xa0μM thidiazuron and with either 0.57xa0μM indole-3-acetic acid (IAA) or 0.41xa0μM picloram. Shoot proliferation was observed in all these treatments. The presence of these plant growth regulators in the culture medium significantly influenced the composition of volatiles as well as morphogenetic responses observed. The number and quality of regenerating shoots and frequency of axillary bud break were highest in medium containing the BA + IAA combination. Sixty-five compounds were identified in the headspace of the in vitro-produced material and plants cultivated in the field. The in vitro shoots emitted both hydrocarbon (limonene, α-pinene) and oxidized (menthone, isomenthone, pulegone) monoterpenes. The composition of monoterpenes differed depending on the type of auxin—rather than cytokinin—in the medium. The emission of phenylallyl compounds, such as estragole, a major compound in field-grown plants, was markedly lower in shoot cultures.

Belamcandae chinensis rhizome--a review of phytochemistry and bioactivity.

Belamcandae chinensis rhizoma, is a rhizome of Iris domestica (syn. Belamcanda chinensis). Under the Chinese name she gan, it is extensively used in Traditional Chinese Medicine and other East Asian phytotherapy systems. Recently, the monograph of Belamcandae chinensis rhizoma has been included in the European Pharmacopeia. This review provides a comprehensive summary and systematizes the literature data on ethnobotanical uses, chemical constituents and biological effects of Belamcandae chinensis rhizoma and its components. The main group of phytochemicals identified in the dried rhizoma are polyphenols such as isoflavones, xanthone glycosides, stilbenes, simple phenols and quinones. Another characteristic class of substances are triterpenopid iridals. The most typical traditional usage of Belamcandae chinensis rhizoma is for healing respiratory diseases but most of pharmacological research so far has been focused on isoflavones and their estrogenic properties. In pharmacological research, it has been mainly considered as a source of tectorigenin--a phytoestrogene with therapeutic potential in hormone-dependent cancer. The most active isoflavones are tectoridin, tectorigenin and irigenin. The available literature indicates that Belamcandae chinensis rhizoma can prevent excessive oxidation of biomolecules based on various antioxidant mechanisms: transition metal ions reduction, inhibition of lipid peroxidation, free radicals scavenging. The other biological activities proven by a number of in vitro studies include: antimutagenic,anti-inflammatory, anti-angiogenic, hypoglycemic. In conclusion, the knowledge about Belamcandae chinensis rhizoma has been growing rapidly in the recent years,but there are still significant gaps in our understanding of its bioactivity, therapeutic value, and roles played by each of the numerous phytochemicals.

Computational evaluation on the binding affinity of non-specific lipid-transfer protein-2 with fatty acids

A computational study was carried out to identify the structural determinant controlling the affinity, specificity and binding strength of several saturated and unsaturated fatty acids with Oryza sativa (Indica group) nonspecific lipid transfer protein (nsLTP2). Association between the number, position and conformation of hydrophobic patches and lipid binding properties of the protein was evidenced by docking analysis. Binding affinity is influenced by the number of carbon atoms, location of double bonds and hydroxyl group in the acyl chain. The results may direct at developing applications in LTP-mediated transport and controlled release of low molecular weight drugs.

A suicide attempt by intoxication with Taxus baccata leaves and ultra-fast liquid chromatography-electrospray ionization-tandem mass spectrometry, analysis of patient serum and different plant samples: case report

BackgroundTaxus (yew) is one of the most frequently reported plants causing potentially fatal outcome when taken incidentally or for suicidal reasons. A fast and reliable method of detection of poisonous compounds or their metabolites is critical in life-saving procedures in cases of yew ingestion. Previously, several chromatographic analytical procedures have been described usually taking longer than one hour of total analysis time.Case presentationIn this report we describe a suicide case study and an ad hoc developed fast method of detection and quantitation of 3,5-dimethoxyphenol – the main taxane metabolite in the blood plasma from the patient as well as the determination of major taxine components in the plant material (Taxus baccata). At present, there is no reasonable alternative for mass spectrometry that could match its high sensitivity and accuracy, and Multiple Reaction Monitoring could be adequate and useful mass spectrometry technique in analyzing and identification of plants material compounds that cause severe poisoning in humans. In the reported case, intensive cardiac care together with the astuteness of the treating physicians not only saved the patient’s life, but also allowed for his complete recovery and return to work.ConclusionsThe development of ultra fast liquid chromatography tandem mass spectrometry UFLC-MS/MS method provides a fast means to confirm yew alkaloids and their metabolite in various material. The applied analytical procedure allows early detection of main metabolite in patient material as well as comparing to those extracted from the plant. In our study, the taxanes remained undetected, probably due to the time elapsing from the patient admittance and collection of plasma. In cases like those reported in this study, retaining the gastric material should be obligatory to confirm the ingestion of yew. The possibility of using this approach in detection of native taxine compounds in human plasma remains to be verified.