Janusz Malarz

Flavonoid production in transformed root cultures of Scutellaria baicalensis.

Summary Agrobacterium rhizogenes LBA 9402 transformed root cultures of Scutellaria baicalensis Georgi (Lamiaceae) were established and examined in respect to their capability to produce flavonoids characteristic of roots of the intact plant. The flavonoids were quantified by RP-HPLC after previous acid hydrolysis of glycosides to the corresponding aglycones. An effect of a nutrient medium composition on growth and flavonoid content in the cultures was studied. Optimum for flavonoid production was half-strength Gamborg B5 medium containing 5-7% sucrose. Roots grown in the medium yielded up to 7% dry weight of baicalein, 1.9 % dry weight of wogonin and 1.3 % dry weight of oroxylin A.

Sesquiterpene lactones in a hairy root culture of Cichorium intybus.

A transformed root culture of Cichorium intybus L. (Asteraceae) was found to produce sesquiterpene lactones of guaiane and germacrane type. Lactucopicrin, 8-desoxylactucin and three sesquiterpene lactone glycosides: crepidiaside B, sonchuside A and ixerisoside D were isolated from the roots. The yield of 8-desoxylactucin reached 0.03 g l-1 at the early stationary phase of the culture.

Caffeic acid derivatives from a hairy root culture of Lactuca virosa

In a search for biologically active phenolics, a hydroalcoholic extract from the hairy roots of Lactuca virosa was fractionated by chromatographical methods. The procedure led to the isolation of a substantial amount of 3,5-dicaffeoylquinic acid (3,5-DCQA)—a potent free radical scavenger. An analytical RP-HPLC separation of the hydroalcoholic extract from the hairy roots allowed identification of further hydroxycinnamates: caftaric acid (CTA), chlorogenic acid (5-CQA) and cichoric acid (DCTA), as well as small amounts of unbound phenolic acids. A time course of growth and caffeic acid derivatives accumulation in the hairy root culture was also investigated. The highest contents of the compounds in the examined roots were detected at the logarithmic phase of growth. The average content of 3,5-DCQA in the roots (ca. 2.5% DW) was at least one order of magnitude higher than that found in roots of Lactuca species and callus culture of L. virosa.

Sesquiterpene lactones in Agrobacterium rhizogenes—Transformed hairy root culture of Lactuca virosa

Investigation of hairy root culture of Lactuca virosa transformed with Agrobacterium rhizogenes resulted in the isolation of eight sesquiterpene lactones, six of which were glycoside derivatives. In addition, stigmasterol together with known triterpenes and their acetates were found. The compounds were identified by spectroscopic methods.

Salicylate and methyl jasmonate differentially influence diacetylene accumulation pattern in transformed roots of feverfew

In hairy root cultures of feverfew (Tanacetum parthenium (L.) Sch. Bip.), treated with methyl jasmonate (MJ), accumulation of spiroketal enol ether type diacetylenes of known deterrent activity was increased about two-fold. The phenomenon was independent of the root clone studied. The maximum total acetylene content (≈2.5 and 1.1% dry weight in clones M2 and I2, respectively) was observed after 72–96 h MJ treatment. Salicylic acid (SA) transiently reduced a content of constitutive spiroketal enol ethers, common for all root clones, but selectively enhanced accumulation of cis-C13-spiroketal enol ether epoxide ((E)-3,4-epoxy-2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4.4]nonane) (2), present in clone M2. Simultaneous addition of SA and MJ to the culture medium influenced diacetylene spectrum in a salicylate-like manner, but accumulation of the epoxide in clone M2 was more abundant (up to 6-fold increase compared with the control).

Root tubers of Lactuca tuberosa as a source of antioxidant phenolic compounds and new furofuran lignans.

From the root tubers of Lactuca tuberosa, a wild edible plant species, nine phenolic compounds were isolated, including two new furofuran lignan glucosides, named lactuberin A and lactuberin B. Their structures were elucidated by spectroscopic methods, especially HRESIMS and 2D NMR techniques. This is the first time that compounds belonging to the epi series of 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane type furofuran lignans have been found in Lactuca species. The total phenolic content of the root tuber extract was evaluated and its major phenolic constituents, caffeic acid, chlorogenic acid and 3,5 dicaffeoylquinic acid, known to possess antioxidant activity, were quantified. Additionally, the root tuber extract showed DPPH radical scavenging activity implying its potential as functional food.

Furofuran lignans from a callus culture of Cichorium intybus

Three new and one known furofuran lignans—syringaresinol derivatives—along with the known phenylpropanoids cichoriin and syringin were isolated from a callus tissue of Cichorium intybus. The compounds were characterised by spectral methods. This is the first report on the presence of furofuran lignans in Cichorium species.

Thymol Derivatives from a Root Culture of Inula helenium

Abstract A root culture of Inula helenium L. was established from leaf explants of aseptic seedlings. An ethanol extract from the lyophilised roots was fractionated using different chromatographic techniques (CC, TLC). The main secondary metabolites found in the root culture were two thymol derivatives: 10-isobutyryloxy-8,9- epoxy-thymol isobutyrate (1) and 10-isobutyryloxy-6- methoxy-8,9-epoxy-thymol isobutyrate (2). The compounds were identified by spectral methods. Quantification of compound 1 in plant material was done by analytical RP-HPLC.

Variation of sesquiterpene lactone contents in Lactuca georgica natural populations from Armenia

A comparative phytochemical study of seven sesquiterpene lactones in natural populations of the wild lettuce Lactuca georgica Grossh. (Asteraceae) was performed, based on 17 accessions derived from seven localities representing three regions in Armenia. The compounds were profiled and quantified in roots and leaves of the plants, grown from achenes (cypselas) in a glasshouse under controlled conditions. The contents of major sesquiterpene lactones were estimated in the plant materials by HPLC/PDA, including the germacranolide glucoside—lactuside A and the guaianolides: lactucin, 11β,13-dihydrolactucin, its three esters (at C-8) with acetic, p-hydroxyphenylacetic and methacrylic acids and its 15-O-glucoside (cichorioside B). The plant roots could be characterized by the occurrence of lactuside A and two 11β,13-dihydrolactucin derivatives (acetate and methacrylate) in relatively high amounts. Lactucin and 11β,13-dihydrolactucin were major sesquiterpene constituents in the plant leaves. An analysis of quantitative results of these seven constituents led to the following conclusions: (1) the sesquiterpene lactone contents varied widely, mostly between-populations for root samples, but mostly within-populations for leaf samples, (2) these differences are likely to be genetically controlled since all accessions were grown under standardized glasshouse conditions. This study is probably the first report of detailed screening of L. georgica natural populations and individuals for any trait. The obtained results show that L. georgica, a species within the primary lettuce gene pool, should be considered as an attractive source of germplasm in further research and improvement of cultivated lettuce (Lactuca sativa).

Major terpenoids from Telekia speciosa flowers and their cytotoxic activity in vitro

Abstract In addition to known constituents of Telekia speciosa, an acetone extract from ray florets of the plant yielded: 5,5ʹ-dibutoxy-2,2ʹ-bifuran (1), 5,5ʹ-diisobutoxy-2,2ʹ-bifuran (2), α-tocopherol (3), β-tocopherol (4), loliolide palmitate (5), a mixture of calenduladiol esters - 16β-hydroxylupeol-3-O-palmitate (7) and 16β-hydroxylupeol-3-O-myristate (8), 1-epiinuviscolide (12), inuviscolide (13), 3-epiisotelekin (16), 4α-hydroxy-9β,10β-epoxy-1β(H)-11(13)-guaien-8α,12-olide (17), 4α-hydroxy-1β(H)-9(10),11(13)-guaiadien-8α,12-olide (18), loliolide (19) and 4β,10β-dihydroxy-1α(H),5α(H)-11(13)-guaien-8α,12-olide (20). Calenduladiol esters and asperilin (14) were the major constituents of the extract. Their cytotoxic effect on human normal prostate epithelial cells (PNT-2), human prostate carcinoma cell lines, human skin fibroblasts (HSF) and human melanoma cell lines was examined in vitro. Triterpene esters showed no cytotoxicity against nearly all cell lines tested, except for Du145 prostate carcinoma cells (IC50 – 62.0 μΜ). Asperilin displayed activity against the cell lines under study, especially against three tested lines of melanomas (A375, IC50 – 17.6 μΜ, WM793, IC50 – 28.2 μΜ and Hs 294T, IC50 – 29.5 μΜ).