This study aimed to identify the regulatory mechanisms of white, blue, red lights on carotenoid and tocochromanol biosynthesis in mung bean sprouts. Results showed that three lights stimulated the increase of the predominated lutein (3.2-8.1 folds) and violaxanthin (2.1-6.1 folds) in sprouts as compared with dark control, as well as β-carotene (20-36 folds), with the best yield observed under white light. Light signals also promoted α- and γ-tocopherol accumulation (up to 1.8 folds) as compared with dark control. The CRTISO, LUT5 and DXS (1.24-6.34 folds) exhibited high expression levels under light quality conditions, resulting in an overaccumulation of carotenoids. The MPBQ-MT, TC and TMT were decisive genes in tocochromanol biosynthesis, and were expressed up to 4.19 folds as compared with control. Overall, the results could provide novel insights into light-mediated regulation and fortification of carotenoids and tocopherols, as well as guide future agricultural cultivation of mung bean sprouts.

Investigations of phytoplankton responses to iron stress in seawater are complicated by the fact that iron concentrations do not necessarily reflect bioavailability. Most studies to date have been based on single species or field samples and are problematic to interpret. Here, we report results from an experimental cocultivation model system that enabled us to evaluate interspecific competition as a function of iron content and form, and to study the effect of nutritional conditions on the proteomic profiles of individual species. Our study revealed that the dinoflagellate Amphidinium carterae was able to utilize iron from a hydroxamate siderophore, a strategy that could provide an ecological advantage in environments where siderophores present an important source of iron. Additionally, proteomic analysis allowed us to identify a potential candidate protein involved in iron acquisition from hydroxamate siderophores, a strategy that is largely unknown in eukaryotic phytoplankton.

Systemic acquired acclimation (SAA) is an important light acclimatory mechanism that depends on the global adjustments of non-photochemical quenching and chloroplast retrograde signaling. As the exact regulation of these processes is not known, we measured time-resolved fluorescence of chlorophyll a in Arabidopsis thaliana leaves exposed to excess light, in leaves undergoing SAA, and in leaves after excess light episode. We compare the behavior induced in wild-type plants with null mutant of non-photochemical quenching (npq4-1). The wild type rosettes exhibit a small reduction of fluorescence decay times in leaves directly exposed to excess light and in leaves undergoing SAA in ambient low light. However in npq4-1 exposition to excess light results in much faster fluorescence decay, which is insensitive to excitation power. At the same time npq4-1 leaves undergoing SAA displayed intermediate fluorescence decay. The npq4-1 plants also lost the ability to optimize florescence decay, and thus chlorophyll a dynamics up to 2 h after excess light episode. The fluorescence decay dynamics in both WT and npq4-1 can be described by a set of 3 maximum decay times. Based on the results, we concluded that functional PsbS is required for optimization of absorbed photon fate and optimal light acclimatory responses such as SAA or after excess light stress.