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• Both G. parviflora and A. dubius were positively affected by the 5°C increase. • The C 3 altered photosynthetic traits and was more sensitive to the 5°C increase. • Both species altered biochemical traits, which may not be useful for screening. • The plant trait network showed both species had high phenotypic plasticity. • Photosynthetic traits were useful for screening the C 3 for temperature tolerance. Wild leafy vegetables are of increasing interest because many have higher concentrations of some beneficial minerals, vitamins and nutrients than commercial crops. Some reports also indicate that they exhibit high levels of tolerance to abiotic stressors associated with climate change. The aim of this study was to investigate whether selected biochemical, physiological (related to photosynthesis) and morphological traits could be used to screen for elevated temperature tolerance in two wild leafy vegetable species, viz. Amaranthus dubius (C 4) and Galinsoga parviflora (C 3). One-month-old seedlings were transferred from a greenhouse to growth chambers and subjected to either ambient [25°C (day)/14°C (night)] or elevated [30°C (day)/19°C (night)] temperatures for 15 days. On days 0, 5, 10 and 15, gas exchange, chlorophyll fluorescence, selected biochemical, physiological and morphological traits were determined. Data for the 24 traits measured were used in plant trait network analyses to establish the populations' phenotypic plasticity, including changes in the interactions/relationships amongst the traits when exposed to elevated temperatures. Sixteen traits showed significant differences between ambient and elevated temperatures on day 15, 11 in G. parviflora only, one in A. dubius only and four in both species. Those shared by the two species were intracellular hydrogen peroxide, electrolyte leakage, ascorbate peroxidase, and superoxide dismutase, while specific leaf area was significantly different in A. dubius only. Both species altered biochemical leaf traits under elevated temperatures, while morphological leaf traits were altered in A. dubius only and photosynthetic leaf traits in G. parviflora only. In G. parviflora , the photosynthetic traits were more sensitive to elevated temperatures than in A. dubius. This suggests that photosynthetic traits may be ineffective for screening C 4 species, due to them being highly evolved to survive in warmer climates. However, the results showed that photosynthetic traits could be useful as screening tools for C 3 photosynthetic pathway species. The plant trait network analyses showed that both species displayed high phenotypic plasticity with a 5°C increase in temperature. We recommend when screening wild leafy vegetables for high temperature tolerance that photosynthetic traits be considered in the context of their phenotypic plasticity. This approach could fast-track the identification of more climate-resilient wild edible species. [ABSTRACT FROM AUTHOR]

Background: Among solar radiation, ultraviolet light is the most harmful for the skin, because of intracellular reactive oxygen species formation, leading to oxidative stress, cell damage and apoptosis. Crucial role in skin protection against oxidative stress play antioxidant enzymes regulated by Nrf2 transcription factor. Some plant-derived polyphenols are known to protect skin fibroblasts against UV through induction of Nrf2-dependent antioxidant genes expression.Purpose: We previously found out that water extracts from Galinsoga sp. herb protected human dermal fibroblasts against UVA-induced oxidative stress and apoptosis. However, which compounds were responsible for such protective action remained unclear. Here, we investigated photoprotective potential and mechanism of action of two main isolated compounds, 2,3,5(2,4,5)-tricaffeoylaltraric acid and 2,4(3,5)-dicaffeoylglucaric acid, on human dermal fibroblasts (NHDF).Study Design/methods: NHDF cells were pretreated with tested compounds (6.25-50 µM) and irradiated with UVA (25 J/cm2). Intracellular ROS and GSH level, cell viability, cell membrane integrity and apoptosis were measured. HO-1 protein expression and Nrf2 transcription factor activation were also assessed.Results: Cells pretreated with tested compounds prior to UVA showed inhibition of intracellular ROS formation and increase of GSH level. Significant increase of cell viability was also observed, as well as decrease of LDH release and a the rate of apoptotic cells in comparison to untreated cells. Furthermore, tested compounds increased HO-1 expression and activated the Nrf2 transcription factor in NHDF cells.Conclusion: Present study demonstrated that caffeic acid derivatives present in Galinsoga parviflora herb, in particular tricaffeoylaltraric acid may protect dermal fibroblasts against UVA-induced oxidative stress through activation of intracellular antioxidative system. Such caffeic acid derivatives are bioactive compounds which might prevent UV-induced photoageing and photocarcinogenesis. [ABSTRACT FROM AUTHOR]

Four new caffeoyl -glucaric and -altraric acid derivatives along with eleven known compounds were isolated from aerial parts of Galinsonga parviflora . Their structures were elucidated by high-resolution spectroscopic studies. The four new compounds were determined as being 2,3,4,5-tetracaffeoylglucaric acid ( 1 ), 2,4,5-tricaffeoylglucaric acid ( 2 ), 2,3,4- or 3,4,5-tricaffeoylaltraric acid ( 3 ) and 2,3(4,5)-dicaffeoylaltraric acid ( 4 ). A reliable criterion for the determination of the linkage position of caffeic acids moieties in glucaric acid derivatives has been proposed, on the basis of detailed analysis of the respective J -couplings, including substitution and solvent influence on the observed values. All hexaric acids derivatives appeared as inhibitors of reactive oxygen species production by stimulated neutrophils. [ABSTRACT FROM AUTHOR]

Galinsoga species are used in folk medicine as anti-inflammatory agents and accelerators for wound healing. They also have reported antioxidant activity. We examined aqueous and ethanolic extracts derived from the Galinsoga herb as potential photoprotectors, as the role of reactive oxygen species (ROS) has implicated in skin damage. The extracts used in the study were standardized by determining the sum of flavonoids, and the amount of caffeic acid and its derivatives. The antioxidant activity of the extracts was evaluated by examining the scavenging of two radicals (O 2 − and H 2 O 2 ) generated in cell-free systems. We also examined the effect on ROS generation by human skin fibroblasts after UV irradiation. In addition we determined the cytotoxicity of the extracts and their protective effect against damage caused by UV irradiation (MTT test, LDH release test and staining with annexine V-FITC/PI). Our findings show that the ethanolic extracts from the herb have cytotoxic effects, while the aqueous extracts from Galinsoga herb have protective activity, in part due to their ability to inhibit ROS generation. In the conclusion the aqueous extracts from the both tested species may be effective as photoprotectors. [ABSTRACT FROM AUTHOR]

Galinsoga parviflora Cav. and Fumaria officinalis L. are well known to have many therapeutic applications based also on their antioxidant activity. Because the antioxidative potential of plant materials is related to the presence of phenolic compounds, we determined their content in both herb extracts. Then the antioxidant potency of the extracts was estimated by measuring ABTS scavenging activity and by Saccharomyces cerevisiae cell assays, including the estimation of viability, respiration coupling and protein carbonylation for the yeast Δ sod1 mutant. This mutant undergoes oxidative stress because of the depletion of the superoxide dismutase form encoded by the SOD1 gene (CuZnSOD). We demonstrated that the antioxidative activities of G. parviflora and F. officinalis extracts coincide with the content of phenolic compounds, namely, phenolic acids. Moreover, we observed a relationship between the extract activities and their effects on the Δ sod1 cell status of energy coupling and protein carbonylation, as well as cell viability. These findings provide new data regarding the mechanism of antioxidative activity of plant phenolic compounds and the potential of the studied herb for application as a functional food ingredient. [ABSTRACT FROM AUTHOR]

Galinsoga parviflora (gallant soldier), Asteraceae, produces two morphologically distinct achenes in a single capitulum: peripheral and central. The morphological, phenological and generative reproduction traits of the progeny derived from peripheral and central achenes that were cultivated in greenhouse conditions were analyzed. Differences between the progeny of various morph types were manifested at different stages of life. The plants of both morph types developed at a similar rate and they entered key phenological phases at the same time except for the flowering stage. The average height of the studied plants was similar on the same days of the experiment. The study showed that plants from peripheral achenes realize the generative reproduction in other pattern than plants from central achenes. The plants from central achenes produce more capitula per plant at the beginning of the fruiting stage, whereas plants from peripheral seeds achieve the highest number of capitula per plant at later stages. Finally, on day 130 of the experiment, the number of capitula per plant of both morphs equalized. At the early fruiting stage, the number of achenes per capitulum of plants from the two morphs did not differ significantly. The number of achenes within one capitulum decreases with plant age in both populations, but the rate of that decline is greater in the progeny of peripheral seeds. The number of peripheral achenes per capitulum in plants from both achene types decreases at a comparable rate. In contrast, the number of central achenes is reduced at a faster rate in plants germinated from peripheral achenes. After day 83, the individuals from peripheral diaspores intensified their reproductive effort; they produced more capitula but with fewer number of achenes than in individuals from central diaspores. On day 130, the number of dispores per plant of the two morphs equalized. The changes of fecundity of peripheral and central progeny with the age of the plant (at different stages of the life cycle of a single plant) contribute to an intensive seed rain throughout the fruiting period. By producing a large number of less fertile capitula with a stable number of peripheral achenes, plants derived from peripheral achenes are able to supply a higher share of peripheral achenes than if they would produce fewer but more fertile capitula. This strategy increases the pool of peripheral achenes. [ABSTRACT FROM AUTHOR]

Abstract: Whilst the importance of arbuscular mycorrhizal fungi (AMF) in invasive spread of some alien plant species has been recently established, it is unclear how such plants respond to AMF from different geographical sources. Besides, influence of different co-occurring plant species on the AMF-mediated invasiveness of alien species, though rarely investigated, is pivotal to the explicit understanding of the feedback between arbuscular mycorrhizal fungi and alien plant invasions. We therefore examined the influence of local (Kashmir Himalyan isolates) and foreign (isolates from Rajasthan, India) AMF on invasiveness of alien Anthemis cotula vis-à-vis the effect of three common co-occurring neighbours, Conyza canadensis, Galinsoga parviflora and Sisymbrium loeselii. Field studies revealed high incidence of Arum-type mycorrhizal colonization in natural populations of A. cotula and the pot trials confirmed the reliance of its invasiveness on AMF with the more favourable effect of local than foreign AMF. The mycorrhizal colonization intensity in field populations of A. cotula was strongly influenced by neighbour identity with major reduction recorded in the presence of S. loeselii (a cruciferous non-host) in comparison to other con-familial neighbours. Pot experiments confirmed the differential effect of co-occurring species on A. cotula''s invasive traits. These results signify that the facilitative role of AMF communities in invasion by some alien plants is contingent upon neighbour identity and the present approach provides not only a framework for further examination of the invasive plant–soil biota feedback, but also many important management implications. [Copyright &y& Elsevier]