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Abstract Invasive species control requires understanding the mechanisms behind their establishment and their interactions with other species. One potential ecosystem alteration influencing the establishment and spread of invasive species is anthropogenic nitrogen enrichment, from sources like introduced or invasive nitrogen (N)-fixing legumes, which can alter competition between native, non-native, and invasive plants. Kentucky bluegrass (Poa pratensis) and N-fixing yellow sweet clover (Melilotus officinalis) are exotic to the Great Plains and are currently invading and degrading native rangelands by altering ecosystem processes and displacing native plants. Therefore, we investigated how N enrichment from yellow sweet clover affects the aboveground biomass production of Kentucky bluegrass and western wheatgrass (Pascopyrum smithii), a native cool-season grass, the ranges of which overlap in the northern Great Plains. In a controlled greenhouse environment, we conditioned experimental pots by growing yellow sweet clover and terminating each plant after 8 wk. Conditioned soils contained ≈ 340% more plant-available N than untreated soils 2 wk after yellow sweet clover death. We then grew Kentucky bluegrass and western wheatgrass transplant seedlings in interspecific and intraspecific pairs in pots conditioned either with or without yellow sweet clover for 12 wk. Aboveground biomass production of both Kentucky bluegrass and western wheatgrass grown in interspecific and intraspecific pairs increased in conditioned soils. However, when grown together in conditioned pots, the increase in Kentucky bluegrass biomass relative to untreated pots (520%) was double that of the increase in western wheatgrass biomass (260%). Our results reveal that Kentucky bluegrass can use increased soil N to produce proportionally more aboveground biomass than western wheatgrass, a native grass competitor. Thus, our results suggest yellow sweet clover and other sources of N enrichment may facilitate the invasion of Kentucky bluegrass. [ABSTRACT FROM AUTHOR]

The sensory-chemical profiles of Finnish honeys (labeled as buckwheat, cloudberry-bog, lingonberry, sweet clover, willowherb and multifloral honeys) were investigated using a multi-analytical approach. The sensory test (untrained panel, n  = 62) was based on scaling and check-all-that-apply (CATA) methods accompanied with questions on preference and usage of honey. The results were correlated with corresponding profiles of odor-active compounds, determined using gas chromatography coupled with mass spectrometry/olfactometry (GC–MS/O). Botanical origins and chemical compositions including sugars were evaluated using NMR spectroscopy. A total of 73 odor-active compounds were listed based on GC–O. Sweet and mild honeys with familiar sensory properties were preferred by the panelists (PCA, R 2 X (1) = 0.7) while buckwheat and cloudberry-bog honeys with strong odor, flavor and color were regarded as unfamiliar and unpleasant. The data will give the honey industry novel information on honey properties in relation to the botanical origin, and consumer preference. [ABSTRACT FROM AUTHOR]

This study aimed to measure the effects of elevated levels of Na + and Cl − on ion concentration, growth, and photosynthetic performance of Melilotus siculus , Tecticornia pergranulata , and Thinopyrum ponticum in pot trials under controlled glasshouse conditions. Experiments were conducted using Na + and Cl − dominant saline soil treated with constituted saline solutions (0, 2.0 and 4.0 dS m −1 Na + or Cl − ). Maximum Na + and Cl − concentration was in T. pergranulata shoots; maximum Na + concentration was in T. pergranulata roots, whereas maximum Cl − in T. ponticum roots. Maximum quantum yield of PSII [Fv/Fm] values did not change significantly. Net-photosynthetic rate [ P n] and stomatal conductance [g s ] values increased and non-photochemical quenching [NPQ] value decreased significantly in T. pergranulata with increasing Na + dominant treatments and the reverse occurred in Cl − dominant treatments. Pn, g s , and NPQ values did not significantly change in T. ponticum with increasing Na + and Cl − dominant treatments. The shoot and root biomasses of T. pergranulata were the maximum at 4.0 dS m −1 Na + dominant treatment. In T. ponticum , the maximum shoot and root fresh masses and shoot dry mass occurred in the control treatment and the maximum root dry mass occurred in the 2.0 dS m −1 Cl − dominant treatment. In T. pergranulata , strong positive correlations occurred between Na + concentration in shoots and salt tolerance (shoot mass over control) and moderately positive correlation occurred between Cl − concentration in shoots and salt tolerance. However, strong negative correlations were observed between Na + and Cl − concentration in shoots and salt tolerance in T. ponticum as well as between Cl − concentration in shoots and salt tolerance in M. siculus . Our glasshouse experiments indicate that 4.0 dS m −1 Cl − solutions in the soil was more intensely damaging than that of Na + . The greatest concentration of both Na + and Cl − was in T. pergranulata under the tested circumstances indicating it to be the candidate of choice for restoring saline soils, followed in capacity by M. siculus and T. ponticum . [ABSTRACT FROM AUTHOR]

Melilotus is one of the most important legume plants, in part due to its production of coumarin, but the genetic diversity among the 18 species remains unclear. In the present study, the analysis of genetic diversity of the Melilotus species was performed with simple sequence repeat (SSR) markers. From the PCR amplification, we selected 18 out of 70 primers that were used in previous studies. Three hundred twenty-six sampled individuals were assayed to study the genetic diversity and polymorphisms based on the SSR markers. All analyzed markers were polymorphic, and 287 alleles were identified, with 15.94 alleles per locus detected. The polymorphism information content ( PIC ) values ranged from 0.71 to 0.93, with an average of 0.87, which indicates that the markers were highly informative. Based on the unweighted pair-group method with arithmetic mean (UPGMA) cluster analysis, we found that the 18 species were divided into two clusters. M. italicus and M.​ speciosus from cluster A and M. indicus and M. segetalis from cluster B were closely related. Population structure analysis suggested that the optimum number of groups was three. From the analysis of molecular variance, 17.79% of the variance was due to species differences, 31.61% of the variance was due to differences among populations within species and the remaining 50.60% was due to differences within populations. The results of the present study showed that these SSR markers will benefit the Melilotus research community for genetics and breeding. Furthermore, this study also established the foundation for future breeding programs, genetic improvement and coumarin production in the Melilotus species. [ABSTRACT FROM AUTHOR]

Soil salinity and root-zone hypoxia often occur together in saline landscapes. For many plants, this combination of stresses causes greater increases in Na + and Cl − in shoots, and decreases in K + , than from salinity alone. These changes in ion concentrations from combined salinity and hypoxia can have more adverse consequences for growth than from salinity alone. The herbaceous forage legume Melilotus siculus naturally occurs in saline soils prone to waterlogging; however, accessions differ in their tolerances, although all form high levels of aerenchyma. We hypothesised that tolerance to combined salinity and hypoxia would be associated with either greater aerenchyma formation in roots or the innate ability of the accessions to regulate tissue ion concentrations. Fifteen accessions of M. siculus were grown in nutrient solution with two salinities (0 or 200 mM NaCl) and two aeration treatments (aerated or hypoxic) for 21 days. Dry mass (shoot and root), root porosity and ion concentrations (Cl − , Na + , K + ) in shoots and roots were assessed. In the M. siculus accessions variation in the shoot dry mass under saline–hypoxic conditions was negatively correlated with shoot Cl − and Na + , and positively correlated with the shoot K + . Shoot ion concentrations under saline–hypoxic conditions were related to concentrations under saline–aerated conditions, but not to the porosity of the main root, which was relatively high (∼18 to 25%). Differences in the tolerance of M. siculus accessions to combined salinity and root-zone hypoxia were mediated by variation in the plants’ ability to regulate ions, and were not related to variation in root porosity, which was relatively high in all accessions. The interaction between salinity and hypoxia was not detrimental to M. siculus , a waterlogging tolerant species. [ABSTRACT FROM AUTHOR]

Abstract: Melilotus is a genus of plants including 20–25 species that are widely distributed throughout the world. Melilotus officinalis, also known as Yellow Melilot, is one of the main species used for clinical purposes. Its characteristic sweet odor, intensified by drying is derived from its coumarin content. It has been indicated in several studies that Melilotus extract application on the skin and administration orally or intravascularly has beneficial effects in ameliorating skin aging and treatment of pimples. In addition, it improves microcirculation and exerts anti-inflammatory effects. M. officinalis is the major ingredient of Semelil (Angipars™) which is a new herbal extract that has been produced in oral, topical, and intravenous forms. Early studies suggest that Semelil may have a role in the healing of diabetic foot ulcers. Among persons diagnosed as having diabetes mellitus, the prevalence of foot ulcers is 4–10%, the annual population-based incidence is 1.0–4.1%, and the lifetime incidence may be as high as 25%. Despite all efforts in treatment of diabetic foot ulcers, the incidence of amputation of lower extremities is still high and there is need for effective and safe treatments for this condition. The value of the new treatments is primarily to prevent amputations, but also to improve quality of life, to control infection and to reduce the costs of treating difficult to heal wounds. This paper presents a brief review of the properties of M. officinalis and its extract Semelil with its role in the treatment of diabetic foot ulcers. [Copyright &y& Elsevier]

Abstract: Annual pasture legumes with high tolerance of combined salinity and waterlogging are needed for saline areas in many rain-fed agricultural regions. Melilotus siculus is an annual legume from saline marshy areas of the Mediterranean with potential use in saline pastures and, based on descriptions of its native habitat, was hypothesised to tolerate combined salinity and waterlogging. Experiments compared M. siculus to Trifolium michelianum and Medicago polymorpha, other annual pasture legumes with reported salt or waterlogging tolerances, with 0–450mM NaCl in hydroponics or in sand culture. Tolerance to combined salinity and waterlogging was also evaluated at 150, 400 and 550mM NaCl in a stagnant deoxygenated nutrient solution. M. siculus was substantially more salt tolerant than the other two species. At 450mM NaCl, shoot DM of M. siculus was 30% of control, compared with only 15% for the other species. M. siculus was also the most tolerant species to combined salinity and stagnant treatment, and produced new leaves even after 14d in stagnant nutrient solution with 550mM NaCl (∼ sea water salinity). In comparison, T. michelianum and M. polymorpha only survived up to 5d in stagnant solution with 400mM NaCl. Even at only 150mM NaCl in stagnant solution, shoot DM was just 30% of control for T. michelianum and M. polymorpha, compared to 60% for M. siculus. Tolerance to combined salinity and waterlogging was associated with higher root porosity and regulation of shoot Na+ and Cl−, with the more tolerant M. siculus having similar shoot Na+ and Cl− concentrations for both aerated-saline and stagnant-saline treatments. In summary, M. siculus is a pasture legume that can grow at high salinity (up to 550mM) even when in combination with waterlogging, as root porosity and associated O2 transport presumably enables continued regulation by the roots of Na+ and Cl− entry under these dual stress conditions. [Copyright &y& Elsevier]

Abstract: Previously unexploited legume species may offer utilization potential where environmental stresses constrain the use of more conventional forage crops. Melilotus indicus (L.) All., Yellow sweet clover, occurs as a weed in different habitats in Egypt. It grows in moderately saline areas, where traditional forage legumes cannot be cultivated. Our extensive field studies have recorded the species in many different habitats ranging from healthy agricultural lands to abandoned saline areas. The studied plants maintained high nodulation capacity (68 – 95%) and nitrogenase activities (about 1.81μmolC2H4 plant−1 h−1) in different habitats. Greenhouse experiments demonstrated that seed germination was maintained at 80% when growing on substrats containing 200mM NaCl and that 25% of the germination capability was preserved when 300mM NaCl was added to the growth medium. The growth rate of seedlings was not significantly affected by 200mM NaCl but was reduced by 30% under 300mM NaCl. It is supposed that M. indicus uses a salt inclusion mechanism for maintaining growth under saline conditions, as it accumulated high amounts of Na+ and Cl− ions. Leaf succulence and indices of leaf water status did not differ among the salt treatments, whereas relative water content was reduced by only 3% and water content at saturation increased by about 14% at high salt concentrations in the growing medium. Our results suggest recommending the cultivation of M. indicus in salt-affected soils, which are widespread and pose a problem for the farmers of Egypt and other countries in the world''s arid belt. [Copyright &y& Elsevier]

Abstract: Ensifer meliloti (formerly Sinorhizobium meliloti) was first considered as a specific microsymbiont of Medicago, Melilotus and Trigonella. However, strains of E. meliloti were recovered from root nodules of various legume species and their symbiotic status still remains unclear. Here, we further investigate the specificity of these strains. A collection of 47 E. meliloti strains isolated in Tunisia from root nodules of Medicago truncatula, Medicago sativa, Medicago ciliaris, Medicago laciniata, Medicago marina, Medicago scutellata, Phaseolus vulgaris, Cicer arietinum, Argyrolobium uniflorum, Lotus creticus, Lotus roudairei, Ononis natrix, Retama raetam, Genista saharae, Acacia tortilis, Hedysarum carnosum and Hippocrepis bicontorta were examined by REP-PCR fingerprinting, PCR-RFLPs of the 16S-23S rDNA IGS, the nifH gene and nifD-K intergenic spacer, and sequencing of 16S rRNA and nodA genes. Their nodulation range was also assessed by cross-inoculation experiments. No clear correlation was found between chromosomal backgrounds and host plants of origin. The nodulation polyvalence of the species E. meliloti was associated with a high symbiotic heterogeneity. On the basis of PCR-RFLP data from the nifH gene and nifD-K intergenic spacer, E. meliloti strains isolated from non-Medicago legumes harboured distinct genes and possessed wider host ranges. Some strains did not nodulate Medicago species. On the basis of nodA phylogeny, the majority of the Tunisian strains, including strains from Medicago, harboured distinct nodA alleles more related to those found in E. medicae than those found in E. meliloti. However, more work is still needed to characterize this group further. The diversity observed among M. laciniata isolates, which was supported by nodA phylogeny, nifH typing and the efficiency profile on M. ciliaris, indicated that what was thought to be bv. medicaginis is certainly heterogeneous. [Copyright &y& Elsevier]

Abstract: Aim of the study: This paper aimed to elucidate the anti-inflammatory effects of EtOAc fraction prepared from Melilotus suaveolens Ledeb ethanol extract with a cellular model of LPS-stimulated RAW 264.7 cell. Materials and methods: Some key pro-inflammatory cytokines and mediators including IL-1β, IL-6, NO, iNOS, COX-2 and TNF-α, two important anti-inflammatory cytokines and mediators IL-10 and HO-1, I-κB and NF-κB were studied by sandwich ELISA, real-time PCR, western blot analysis and immunocytochemistry. At last a HPLC fingerprint was taken to evaluate the fraction. Results: The EtOAc fraction could significantly inhibit the production of IL-1β, IL-6, NO, TNF-α, COX-2 in LPS-stimulated cell than that of single LPS-stimulated cell (p <0.01 or p <0.05), and the extract could increase the production of IL-10 and HO-1 than that of single LPS intervention cell (p <0.01 or p <0.05). Meanwhile, the extract also could inhibit the production of NF-κB compared to single LPS-stimulated cell. All the results showed that the extract had a good anti-inflammatory effect on LPS-stimulated RAW264.7 cell. Conclusions: Taken together, the anti-inflammatory actions of M. suaveolens Ledeb EtOAc fraction might be due to the down-regulation of IL-1β, IL-6, NO, TNF-α and COX-2 via the suppression of NF-κB activation, and another pathway was up regulating the production of IL-10 and HO-1. Meanwhile, the EtOAc fraction might be further studied to isolate the active anti-inflammatory ingredients besides coumarin. [Copyright &y& Elsevier]

Abstract: In Ethiopian traditional medicine, Melilotus elegans Salzm. ex Ser. (Leguminosae) is used for the treatment of haemorrhoids and lacerated wounds. In view of its wide spread use and proven anti-inflammatory activity, 80% methanolic extract of the leaves was formulated into creams. HPLC/UV and MS studies revealed the presence of flavonoids, of which kaempferol was the major aglycone. Quantitative estimation of kaempferol in the hydrolyzed extract as determined by HPLC/UV was found to be 16.3±0.93μg/mg (n=6, range) of extract. The in vitro release profiles of kaempferol glycosides (quantified as kaempferol equivalent) from the cream formulations in a multilayer membrane system indicated that a lipophilic cream of the extract provides higher release of kaempferol glycosides than hydrophilic and amphiphilic ones. Over a study period of 4h, the lipophilic cream released 66±5.70% of kaempferol glycosides, while the hydrophilic and amphiphilic creams resulted in 55±2.77 and 38±2.30% release, respectively. [Copyright &y& Elsevier]