Pollen colour morphs take different paths to fitness.

Colour phenotypes are often involved in communication and are thus under selection by species interactions. However, selection may also act on colour through correlated traits or alternative functions of biochemical pigments. Such forms of selection are instrumental in maintaining petal colour diversity in plants. Pollen colour also varies markedly, but the maintenance of this variation is little understood. In Campanula americana, pollen ranges from white to dark purple, with darker morphs garnering more pollinator visits and exhibiting elevated pollen performance under heat stress. Here, we generate an F2 population segregating for pollen colour and measure correlations with floral traits, pollen attributes and plant-level traits related to fitness. We determine the pigment biochemistry of colour variants and evaluate maternal and paternal fitness of light and dark morphs by crossing within and between morphs. Pollen colour was largely uncorrelated with floral traits (petal colour, size, nectar traits) suggesting it can evolve independently. Darker pollen grains were larger and had higher anthocyanin content (cyanidin and peonidin) which may explain why they outperform light pollen under heat stress. Overall, pollen-related fitness metrics were greater for dark pollen, and dark pollen sires generated seeds with higher germination potential. Conversely, light pollen plants produce 61% more flowers than dark, and 18% more seeds per fruit, suggesting a seed production advantage. Results indicate that light and dark morphs may achieve fitness through different means-dark morphs appear to have a pollen advantage whereas light morphs have an ovule advantage-helping to explain the maintenance of pollen colour variation.

Platycodin D Attenuates Airway Inflammation in a Mouse Model of Allergic Asthma by Regulation NF-κB Pathway.

In this work, the anti-asthma potential of platycodin D (PLD) was studied by investigation of its effect to suppress airway inflammation, a murine model of asthma and the possible mechanisms. A total of 50 mice were randomly assigned to five experimental groups: control, ovalbumin (OVA), OVA+dexamethasone (2 mg/kg) and OVA+PLD (40, 80 mg/kg). Airway resistance (Raw) were measured; airway histological studies were evaluated by the hematoxylin and eosin (HE) staining; interleukin-4 (IL-4), interleukin-5(IL-5), and interleukin-13 in bronchoalveolar lavage fluid (BALF) were evaluated by enzyme-linked immunosorbent assay (ELISA); NF-κBp65, p-NF-κBp65, p-IKKα, IKKα, p-IKKß, p-IкBα, and IкBα of airway were measured by Western blotting. Our study demonstrated that PLD inhibited OVA-induced increases in Raw and eosinophil count in airway; IL-4, IL-5, and IL-13 were recovered in BALF. Histological studies demonstrated that PLD substantially inhibited OVA-induced eosinophilia in airway tissue. Western blotting studies demonstrated that PLD substantially inhibited NF-κB pathway. These findings suggest that PLD may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.

Enhanced accumulation of phytosterol and triterpene in hairy root cultures of Platycodon grandiflorum by overexpression of Panax ginseng 3-hydroxy-3-methylglutaryl-coenzyme A reductase.

3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) catalyzes the rate-limiting step in the mevalonate pathway. To elucidate the functions of HMGR in triterpene biosynthesis, Platycodon grandiflorum was transformed with a construct expressing Panax ginseng HMGR (PgHMGR). We used PCR analysis to select transformed hairy root lines and selected six lines for further investigation. Quantitative real-time PCR showed higher expression levels of HMGR and total platycoside levels (1.5-2.5-fold increase) in transgenic lines than in controls. Phytosterols levels were also 1.1-1.6-fold higher in transgenic lines than in controls. Among these lines, line T7 produced the highest level of total platycosides (1.60 ± 0.2 mg g(-1) dry weight) and α-spinasterol (1.78 ± 0.16 mg g(-1) dry weight). These results suggest that metabolic engineering of P. grandiflorum by Agrobacterium-mediated genetic transformation may enhance production of phytosterols and triterpenoids.

Comprehensive analysis of Phyteuma orbiculare L., a wild Alpine food plant.

Plants which have been traditionally eaten by the alpine population may provide new opportunities for agricultural development in mountain regions. In this context we have investigated the chemical composition of Phyteuma orbiculare (Campanulaceae), a perennial herb whose leaves have been eaten as salad by rural populations in Valais (Switzerland). Extracts of different polarities were subjected to comprehensive metabolite profiling using a dereplication platform combining HPLC-PDA-MS, and offline NMR analysis. Twenty-three compounds, including various phenolic glycosides, a new dimeric phenylpropanoid glucoside, saponins, and fatty acids were identified online, or after targeted isolation. Selected phenolic constituents were quantitatively assessed by HPLC-PDA analysis. In addition, substances relevant for nutrition, such as ß-carotene, fatty acids, ascorbic acid and minerals were quantified in leaves and flowers. The antioxidant capacity was determined with an ORAC assay, and total phenolic compounds were quantified. Finally, the phytochemical profile was compared to that of the related species P. spicatum, P. hemisphaericum and P. ovatum.