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The objective of this study was to determine the concentrations of isoflavones in the cultivars and ecotypes of red clover (Trifolium pratense L.) in a whole above ground part of a plant and separately in stems, leaves and flowers at flowering stage. Isoflavones were extracted using acidified aqueous methanol and subsequent analyses of the extracts were carried out by ultra-performance liquid chromatography coupled with a photodiode array detector. Red clover accumulated the highest concentrations of formononetin (51%) and biochanin A (40%) at flowering stage.

Only a few species of the large Astragalus genus, widely used for medicinal purposes, have been thoroughly studied for phytochemical composition. The aim of our research was to investigate the rarely studied species A. glycyphyllos L. and A. cicer L. for the distribution of mineral elements and phytochemicals in whole plants at two growth stages and in morphological fractions. We also investigated the capacity of the plant extracts to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and to chelate ferrous ions. Chemical composition and antioxidant properties depended on species, maturity, and plant part. Herbal material of A. glycyphyllos was richer in Fe, total phenolics, and flavonoids, whereas extracts of A. cicer showed a higher antioxidant activity. Young plants had more isoflavones, showed greater quenching of DPPH radicals, and exhibited better mineral profiles than flowering plants. Among plant parts, leaves were the most valuable plant material according to most characteristics investigated. Isoflavone concentration in flowers was lower than in leaves and stems. None of the Astragalus samples contained detectable amounts of the alkaloid swainsonine. The study demonstrates the potential of plant material from two Astragalus species as a valuable source of iron, phenolic substances including isoflavones, free-radical scavengers, and Fe2+ chelators for pharmaceutical use.

Approaching switchgrass (Panicum virgatum L.) as a multifunctional energy plant, it is important to comprehensively study the composition and partitioning of organic substances in the biomass. The character of carbohydrates and lignin concentration variation was assessed in switchgrass biomass cut at two maturity stages (heading and seed filling) in the first and second harvest years. Quality components partitioning in the biomass of aboveground plant parts was examined in leaves, stems and panicles of the most productive switchgrass accessions cut at seed filling. The concentrations of lignocellulose (NDF), cellulose (Cel), sum of structural carbohydrates (holocellulose -HoCel), sum of nonstructural and structural carbohydrates (ΣCH 2 O) and lignin in switchgrass biomass of both plant development stages in the second harvest year were significantly higher, whereas an average hemicellulose (HCel) concentration was significantly lower compared with the respective parameters in the first harvest year. The concentrations of nonstructural carbohydrates (NSC) and their individual fractions (water soluble carbohydrates (WSC) and starch) in biomass were similar both in the first and second harvest years. The concentrations of NDF, Cel, HoCel and ΣCH 2 O and particularly lignin at seed filling were significantly higher compared with the respective data at heading in both harvest years. High lignin concentration (105 g kg -1 dry matter (DM)) in switchgrass biomass at seed filling in the second harvest year showed its great suitability for solid biofuel production. Considerable amount of ΣCH 2 O (693-742 g kg -1 DM) indicated that switchgrass biomass at this stage fits for the second-generation bioethanol production. At heading, switchgrass in the second harvest year produced quite a high NSC yield (an average 28.4 g plant -1 ) and low lignin output (an average 19.3 g plant -1 ), which is a favourable feature of feedstock for biogas production, biomass at seed filling is less suitable for that than at heading. Switchgrass plant part significantly (P < 0.01) affected the concentration of all biomass quality attributes tested, but did not affect HCel concentration. Accessions' DM yield correlated positively with NDF (r = 0.781, P < 0.05), Cel (r = 0.882, P < 0.01) and lignin (r = 0.517) and negatively with WSC and NSC (r = −0.982, −0.959; P < 0.01).

An average dry ma�er yield structure (three cuts per growing season) in relation to agronomically valuable characteristics of six forage grass species and a year of herbage utilization was studied over the period of 1989-2002 in Lithuania. The most productive species of the first cut of two years of herbage utilization were Phleum pratense (P < 0.01) and Festulolium hybrids (P < 0.05) (average dry ma�er yield were 7.42 and 6.66 t/ha, respectively), moderately productive -Festuca pratensis, Dactylis glomerata and Lolium perenne (5.58, 5.42 and 5.20 t/ha), significantly lower (P < 0.01) yielding was Poa pratensis (4.19 t/ha). During two years of herbage utilization Dactylis glomerata produced significantly (P < 0.01) higher dry ma�er yield of a�ermath -7.30 t/ha. Other grass species were ranked in the following order: Festulolium hybrids 5.85 t/ha, Festuca pratensis 4.94 t/ha, Poa pratensis 4.57 t/ha, Lolium perenne 4.48 t/ha, and Phleum pratense 3.92 t/ha. Dactylis glomerata and Poa pratensis distinguished by the highest a�ermath percent in the structure of the annual dry ma�er yield (57.7 and 52.2%). Phleum pratense formed an especially poor a�ermath -only 34.6%. An average annual dry ma�er yield data analysis of two years of herbage utilization over the period of [1989][1990][1991][1992][1993][1994][1995][1996][1997][1998][1999][2000][2001][2002] showed that Dactylis glomerata and Festulolium hybrids were most productive (P < 0.01) species.

Introduction:Clover has attracted considerable interest not only as a valuable livestock forage plant, but also as an important source of isoflavones. The current study was aimed to assess the variation of concentration of three isoflavones in clover species grown under a cool temperate climate environment in Lithuania.Materials and Methods:Isoflavone contents were quantified in the plant parts of 21 accessions belonging to five perennial species of genus Trifolium (T. pratense, T. repens, T. medium, T. rubens, and T. pannonicum). Daidzein, formononetin, and genistein concentrations were quantified in separate plant parts by reversed-phase high-performance liquid chromatography. The analyte extraction was performed from dried and ground leaves, stems, flowers, and roots. The procedure included acid hydrolysis of isoflavone glycosides to aglycones.Results:According to the averaged sum of the three isoflavones quantified in leaves-stems-flowers, the five clover species ranked as follows: T. medium (7.54-3.62-2.31 mg/g) >T. pratense> T. rubens> T. pannonicum> T. repens (0.191-0.204-0.171 mg/g). The contribution of individual compound to the total isoflavone content depended on the species, accession, and plant part. The major part of the isoflavones is concentrated in leaves or stems; however, there is a great variation also.Conclusion:There exists a large variation in the total as well as in individual concentration of isoflavones among the clover species and plant parts and within species. With regard to isoflavone concentration and variability within species, some accessions of T. medium and T. pratense can be considered a highly promising source of phytoestrogens.

Perennial legumes have been used as edible or medicinal plants since ancient times. The focus of the current study are perennial legumes-Trifolium pratense L., T. medium L., Medicago sativa L., M. lupulina L., Onobrychis viciifolia Scop., Astragalus glycyphyllos L. and A. cicer L.-of branching stage as a potential source of value-added ingredients for healthy food. Freeze-dried samples were analysed for proximal composition, mineral, isoflavone and coumestrol contents as well as for antimicrobial activity. Legumes were protein-rich (23.0/100 g on average). Mineral contents in 100 g of plant dry matter averaged: K 2.64 g, Ca 1.81 g, Mg 0.475 g, P 0.324 g, Zn 2.76 mg and Fe 37.8 mg. According to the total amount of phytoestrogens, the species ranked as follows: T. medium (34.4 mg/g)) T. pratense) O. viciifolia C M. sativa = A. cicer = M. lupulina C A. glycyphyllos (0.207 mg/ g). Extracts of legumes, especially that of O. viciifolia, exhibited noticeable potency to inhibit the growth of Grampositive and Gram-negative bacteria. Perennial legumes of branching stage can be used as protein, mineral and phytoestrogen rich source for food ingredients and supplements.

Field trials were carried out at the Lithuanian Institute of Agriculture in 2006. The tests involved 120 genotypes of 9 major grass species bred for turf in Lithuania: Festuca rubra L. (subsp. commutata and subsp. rubra) and Festuca ovina L., Poa L. and Poa compressa L., Agrostis capillaris L., Lolium perenne L., Koeleria glauca DC and Deschampsia caespitosa Beauv. A large part of the genetic resources were collected in various natural habitats of Lithuania and other countries (Latvia and Estonia).The aim of this work was to estimate drought susceptibility of turfgrass species and genotypes.Experimental findings suggest that drought has a severe adverse effect on the quality of all the turfgrass species tested. After 75 days of drought, the ornamentality of various turfgrass species declined by 58.9% (Festuca ovina) to 83.3% (Deschampsia caespitosa). According to drought resistance, the test species can be ranked in the following sequence: Festuca ovina > Lolium perenne = Poa compressa > Poa pratensis = Koeleria glauca > Festuca rubra subsp. Rubra > Festuca rubra subsp. Commutata > Agrostis capillaris > Deschampsia caespitosa.During the test period, drought resistance of individual varieties or breeding lines was revealed. The most resistant genotypes were identified within each species.