The thermal degradation of β-carotene in air was investigated. The sample was heated at different temperatures (90, 100, 115, and 130 °C) for periods of up to 8 h to perform a complete kinetic study, the product analysis having been carried out via infrared spectroscopy in attenuated total reflectance mode coupled to density functional theory (DFT) calculations. The kinetics of this thermal degradation process was found to follow a first-order scheme, with rate coefficients varying from k 90 °C = (2.0 ± 0.3) × 10 −3 to k 130 °C = (11.0 ± 0.7) × 10 −3 min −1 , the experimental activation energy having been calculated as (52 ± 1) kJ mol −1 . This E a value is close to the DFT energies corresponding to a C 15−15′ or a C 13−14 cis−trans isomerization, followed by the formation of a carotene−oxygen diradical, which was characterized for the first time. Comparison between the experimental and calculated infrared data confirmed the C 15−15′ -cis rupture as the predominant reaction pathway and retinal as the major degradation product.

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Corema album (L.) D. Don is a wild maritime shrub endemic to the Iberian Peninsula, which contains bioactive compounds with promising chemoprotective activity. The present work reports the first study of the edible fruits of this potentially health‐beneficial plant by complementary Raman and infrared techniques. Unique vibrational signatures were obtained for each part of the Corema album berries, revealing distinct chemical compositions for the skin (outer and inner) and the seeds, particularly regarding the content in phenolic derivatives, unsaturated fatty acids, and waxy polymers.

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Nitrogen (N) recycling is a key mechanism to ensure the sustainability of miscanthus production with no or small fertiliser inputs, but little is known on the subject in miscanthus species other than the most cultivated Miscanthus × giganteus. This field experiment on Miscanthus × giganteus and Miscanthus sinensis quantified plant biomass and N stock dynamics during two years. Endogenous net N fluxes, calculated by the difference in plant N content throughout time, were higher in Miscanthus × giganteus than in Miscanthus sinensis. Indeed, 79 kg N ha -1 and 105 to 197 kg N ha -1 were remobilized during spring and autumn respectively for Miscanthus × giganteus, as opposed to 13 to 25 kg N ha -1 and 46 to 128 kg N ha -1 for Miscanthus sinensis. However, their N recycling efficiency, defined as the ratio between N remobilisation fluxes and the maximum above-ground N content, did not differ significantly. It ranged from 8 to 27% for spring remobilisation and from 63 to 74% and 24 to 38% for autumn remobilization calculated on above-ground and below-ground N respectively. Exogenous N, the main source of N to constitute maximum plant N content for all genotypes, was provided by fertilisation (22 to 24%) and organic matter mineralisation or other sources (43 to 59%). During winter, 50 to 56% of plant N content was lost. Abscised leaves constituted an additional loss of 6 to 12%. Our results show that Miscanthus sinensis is as efficient as Miscanthus × giganteus and as performant as other perennial species concerning N functioning.