Foliar Selenium (Se) fertilizer has been widely used to accumulate Se in rice to a level that meets the adequate intake level. The Se content in brown rice (Oryza sativa L.) was increased in a dose-dependent manner by the foliar application of sodium selenite as a fertilizer at concentrations of 25, 50, 75, and 100 g Se/ha. Selenite was mainly transformed to organic Se, that is, selenomethionine in rice. Beyond the metabolic capacity of Se in rice, inorganic Se also appeared. In addition, four extractable protein fractions in brown rice were analyzed for Se concentration. The Se concentrations in the glutelin and albumin fractions saturated with increasing Se concentration in the fertilizer compared with those in the globulin and prolamin fractions. The structural analyses by fluorescence spectroscopy, Fourier transform infrared spectrometry, and differential scanning calorimetry suggest that the secondary structure and thermostability of glutelin were altered by the Se treatments. These alterations could be due to the replacements of cysteine and methionine to selenocysteine and selenomethionine, respectively. These findings indicate that foliar fertilization of Se was effective in not only transforming inorganic Se to low-molecular-weight selenometabolites such as selenoamino acids, but also incorporating Se into general rice proteins, such as albumin, globulin glutelin, and prolamin, as selenocysteine and selenomethionine in place of cysteine and methionine, respectively.

The fruit of Akebia trifoliata is popular in Asia, but researches concerning the phytochemicals of A. trifoliate pericarp extract (APE) and their metabolites, bioavailability, metabolism and anti-inflammatory activity in vivo are less known. In the present study, the chemical constituents of APE and their metabolites of rats after oral administration were identified using UPLC-LTQ-Orbitrap-MS/MS. A total of 18 compounds were tentatively characterized in APE, while 8 original compounds and 8 metabolites were observed in plasma, and 10 original compounds and 39 metabolites were detected in urine. Deglycosylation, glucuronidation, methylation and sulfation were the reactions that mainly occurred in the metabolism in vivo. Meanwhile, APE supplementation decreased dextran sulphate sodium (DSS)-induced colitis in mice, ameliorating epithelial barrier disruption, suppressing the proliferation and infiltration of immune cells, modulating the secretion of nitric oxide (NO) and prostaglandin E₂ (PGE₂), decreasing the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as well as regulating oxidative stress in vivo. The results suggested that APE triterpenoids and their metabolites as major contributors to anti-inflammatory activities, providing a scientific basis for the use of APE as a functional food to ameliorate colon health in humans.

Acyl migration (AM) is the main side reaction in the large-scale, regio-specific lipase catalyzed production of structural triglycerides (STs). A detailed understanding of the mechanism of AM was obtained during the process of lipase-catalyzed schemes (LCSs), which play a vital role in improving the quality and total yield of STs. However, currently, the mechanism of AM remains controversial. Herein, the two mechanisms (non-catalyzed (NCM) and lipase-catalyzed (LCM)) of AM have been analyzed in detail by the density functional theory (DFT) at the molecular level. Based on the computational results, we concluded that the energy barrier of the rate-limiting step in the LCM was 18.8 kcal/mol, which is more in agreement with the available experimental value (17.8 kcal/mol), indicating that LCM could significantly accelerate the rate of AM, because it has an energy barrier ~2 times lower than that of the NCM. Interestingly, we also found that the catalytic triad (Asp-His-Ser) of the lipase and water could effectively drop the reaction barrier, which served as the general acid or base, or shuttle of the proton.