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1(a) and 1(b), respectively, it is clear that this feature emerges specifically as a result of HT activity[7] - remaining hidden by the inhomogenous broadening when the system is only vibronically mixed by FC activity through a Huang-Rhys factor similar to those found in LHCII.[9] In the model, this side-band can only be observed when additional vibronic mixing through HT activity is included. A growing body of work has pointed to vibronic mixing as a crucial design principle for efficient energy and charge transfer in natural[[1], [3]] and artificial systems.[[4]] Notable among these studies was the recent observation of vibronically promoted ultrafast energy flow in the major antenna complex of green plants and algae light-harvesting complex II (LHCII) - the most abundant membrane protein on the Earth[6] - via the emerging experimental technique two-dimensional electronic-vibrational (2DEV) spectroscopy.[3] This spectroscopy, which correlates electronic and nuclear degrees-of-freedom, shows promise for providing mechanistic insight into vibronic coupling; however, explicit theoretical input is necessary to extract such a detail. Electronic linear absorption spectra (top row) and 2DEV spectra (bottom row) for a heterodimer model without (a) and with (b) HT activity and (c) LHCII at 77 K. [Extracted from the article]

Fucoxanthin is an algae-specific xanthophyll of aquatic carotenoid. It is prevalent in brown seaweed because it functions as a light-harvesting complex for algal photosynthesis and photoprotection. Its exceptional chemical structure exhibits numerous biological activities that benefit human health. Due to these valuable properties, fucoxanthin's potential as a potent source for functional food, feed, and medicine is being explored extensively today. This article has thoroughly reviewed the availability and biosynthesis of fucoxanthin in the brown seaweed, as well as the mechanism behind it. We included the literature findings concerning the beneficial bioactivities of fucoxanthin such as antioxidant, anti-inflammatory, anti-obesity, antidiabetic, anticancer, and other potential activities. Last, an additional view on its potential as a functional food ingredient has been discussed to facilitate a broader application of fucoxanthin as a promising bioactive compound. [ABSTRACT FROM AUTHOR]

Photosynthesis involves light‐harvesting complexes where an array of antenna pigment channels the absorbed solar energy to the reaction centre of a photosystem. This work reports a supramolecular dendrimer‐dye assembly that mimics the natural light‐harvesting mechanism. A dendrimeric molecule based on two‐fluorophores has been constructed with three coumarin units at the end of three long arms and a 7‐diethylaminocoumarin unit at the interior. The molecule self‐aggregates in water into spherical micelles, which can encapsulate a rose‐bengal dye (RB). On excitation, peripheral coumarin units shuttled the energy to the loaded RB dye reaction center via a two‐step cascade resonance energy transfer (RET). The energy absorbed in the periphery is funnelled efficiently, resulting in a strong emission from the dye that resembles an energy funnel. The energy transfer cascade has been studied with both steady‐state and time‐resolved fluorescence spectroscopy. Molecular dynamics simulations of the self‐assembled aggregates in water were also in agreement with the experimental observations. [ABSTRACT FROM AUTHOR]

Although the study did not find kelp pigment impairment caused by exposure to coal constituents, kelp pigment analysis is still a useful means of assessing kelp health. Methods for assessing the potential for elevated concentrations of environmental chemicals that result in adverse health effects on aquatic macrophytes, including kelp, are limited. [Extracted from the article]